SEARCH
Search DetailsSATO HarumiGraduate School of Human Development and Environment / Department of Human Environmental ScienceProfessor
Research activity information
■ Award- Jun. 2009 資生堂, 第2回 資生堂 女性研究者サイエンスグラント, 女性研究者
- Nov. 2007 ひょうご女性未来会議, ひょうご女性未来会議 縹(はなだ)賞, 女性
- Oct. 2005 株式会社堀場, 第2回 堀場雅夫賞, 振動分光
- Feb. 2004 高分子学会, 高分子学会研究奨励賞, 高分子研究
- Dec. 2002 P&G, P&G Recognition Award (業績賞), Out standing scientific contribution toward the fundamental understanding of bio-based biodegradable polymers.
- Corresponding, Elsevier BV, Mar. 2025, Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, 329, 125576 - 125576, English[Refereed]Scientific journal
- Corresponding, Elsevier BV, Mar. 2025, Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, 329, 125492 - 125492, English[Refereed]Scientific journal
- The samples investigated were prepared by seeking poly(ϵ-caprolactone) (PCL) films in seawater for the study of marine degradation processes. Raman mapping measurements in the low-frequency region and the C═O stretching region were used for investigating the strength of the CH···O═C hydrogen bonding and the changes in the crystallinity of PCL, respectively, in its marine degradation process. During the marine degradation of the PCL film, the amorphous parts of the film decomposed and flow away in the seawater. A band at around 60 cm-1 reflecting intermolecular CH···O═C hydrogen bonds showed a weakening of hydrogen bonds in the crystal structure of PCL. Three-dimensional (3D) Raman mapping developed by the C═O stretching region indicated that the marine degradation started from the surface of the annealed PCL film. However, 3D Raman mapping measurements in the low-frequency region showed no significant difference in the strength of the hydrogen bonding between a film surface and an inside after marine degradation of day 7. These findings suggest that the crystallinity changes mainly near the film surface, but changes in the strength of the hydrogen bonding occur both near the surface and inside of the PCL film.Jun. 2024, ACS Applied Polymer Materials, 6(11) (11), 6408 - 6415[Refereed]Scientific journal
- Intermolecular interactions in poly(trimethylene terephthalate) (PTT) are investigated using far-infrared (FIR), terahertz (THz), and low-frequency Raman spectroscopy, interatomic distance calculations, natural bond orbital (NBO) analysis, and quantum chemical calculations (QCCs). The parity of the crystal structure is explored through the vibrational spectroscopy by comparing PTT with poly(ethylene terephthalate) (PET) and poly(butylene terephthalate) (PBT), where the structural difference only lies in the number of CH2 groups. Interatomic distance calculations and NBO analysis suggested the presence of CH···O═C hydrogen bonds between adjacent molecules of PTT. This hydrogen bond appears as a band at 88 cm-1 in the THz spectrum and 90 cm-1 in the low-frequency Raman spectrum. In poly(m-methylene terephthalate) with an odd number of CH2 groups (PTT: CH2 = 3), the molecular chain forms a crystal structure with repeated Z-shaped bends, whereas with an even number of CH2 groups (PET: CH2 = 2, PBT: CH2 = 4), a crystal structure is formed in which the repeating units are arranged in the same direction with respect to the fiber axis. The parity of this crystal structure is reflected in the low-frequency spectra. Therefore, it is clear that vibrational spectroscopy in the low-frequency region is a useful technique for detecting the parity of the polymers.Jun. 2024, Macromolecules, 57(11) (11), 5340 - 5349[Refereed]Scientific journal
- Elsevier BV, May 2024, Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, 312, 124052 - 124052, English[Refereed]Scientific journal
- Raman images were constructed for polypropylene (PP) films before and after ultraviolet (UV) irradiation (100 mW, 248–436 nm) for 10 h using several intensity ratios of Raman bands that are sensitive to crystallization of PP. In the images of PP films before the irradiation the intensity ratios are nearly uniform for the films but for those of the PP films after the irradiation, the ratios become large with a mottled pattern, indicating that recrystallization occurs in the PP films upon the irradiation of the UV light. The UV-irradiated PP films show worm-like shaped structures in few micrometer order representing the recrystallization of PP. The temperature gradient of PP is low (273 K), and thus, it is very likely that due to UV energy and polymer fragmentation, PP molecules become more mobile and some parts of molecular chains in amorphous parts of PP molecules lead to their rearrangement and recrystallization. In this study, we demonstrate that Raman imaging clearly detects subtle changes in the crystallinity with a micrometer order structure which morphological images cannot observe.Corresponding, SAGE Publications, Mar. 2024, Applied Spectroscopy, English[Refereed]Scientific journal
- Singlet fission can generate an exchange-coupled quintet triplet pair state 5TT, which could lead to the realization of quantum computing and quantum sensing using entangled multiple qubits even at room temperature. However, the observation of the quantum coherence of 5TT has been limited to cryogenic temperatures, and the fundamental question is what kind of material design will enable its room-temperature quantum coherence. Here, we show that the quantum coherence of singlet fission-derived 5TT in a chromophore-integrated metal-organic framework can be over hundred nanoseconds at room temperature. The suppressed motion of the chromophores in ordered domains within the metal-organic framework leads to the enough fluctuation of the exchange interaction necessary for 5TT generation but, at the same time, does not cause severe 5TT decoherence. Furthermore, the phase and amplitude of quantum beating depend on the molecular motion, opening the way to room-temperature molecular quantum computing based on multiple quantum gate control.Jan. 2024, Science advances, 10(1) (1), eadi3147, English, International magazine[Refereed]Scientific journal
- Polymers with crystallizable side chains have numerous applications, and their properties depend on their crystal morphologies and phase separation. Structural analysis on a wide spatial scale plays an important role in controlling the thermal properties and higher-order structures of these polymers. In this study, we elucidated the melting and crystallization processes of copolymers with varying crystallizable side-chain fractions over a wide spatial range. Differential scanning calorimetry revealed that the enthalpies of melting and crystallization increased linearly with increasing crystallizable side-chain fraction. The results of wide-angle X-ray scattering indicated that the crystal lattice was hexagonal. Conversely, spherulite-like higher-order architectures with linear structures and radial spreading were observed in the highly crystallizable components, but no micrometer-scale structures were observed in the less crystallizable components. In situ small-angle X-ray scattering was used to elucidate the phase separation and mixing processes. Lamellar crystallites were observed at crystallizable side-chain fractions of >55 wt.%, whereas small crystallites were observed at fractions of <45 wt.%. At temperatures above the order-disorder transition temperature, density fluctuations caused by correlation holes were observed. These properties have a strong effect on the crystallizable side-chain fraction.MDPI AG, Dec. 2023, Polymers, 15(24) (24), 4663 - 4663, English[Refereed]Scientific journal
- American Chemical Society (ACS), Aug. 2023, The Journal of Physical Chemistry B, 127(35) (35), 7602 - 7614, English[Refereed]Scientific journal
- Elsevier BV, Oct. 2022, Chemical Physics Letters, 805, 139976 - 139976, English[Refereed]Scientific journal
- Abstract Raman spectra of water and supercooled water were measured in the temperature range of −6 to 18°C with every 2°C step. The obtained spectra were analyzed for the 3750–2850 and 400–100 cm−1 regions by two‐dimensional correlation (2D‐COS) Raman spectroscopy. As previously reported, there are three bands at around 3620, 3420, and 3200 cm−1 in the OH‐stretching region. These bands were assigned to the OH‐stretching modes of dangling (Dang) bonds of water, destructured, and structured water species, respectively. A pair of clear peaks appear in asynchronous 2D‐COS maps in the 3750–2850 cm−1 region of Raman spectra of water developed using the spectra measured in the temperature ranges of −6 to 2°C, 0 to 8°C, and 8 to 18°C, and they are similar to each other, suggesting nonlinear (convex) temperature‐dependent increase and decrease of the two kinds of water species. A power spectrum calculated along the diagonal line in the synchronous spectrum in the −6 to 18°C range has a peak at 3171 cm−1 with a broad shoulder at around 3400 cm−1. These peaks at 3171 and 3400 cm−1 may be assigned to the collective mode and its local mode of structured water, respectively. In the 400–100 cm−1 region, there is a broad feature centered at 185 cm−1 assigned to the intermolecular stretching mode of water molecule. Close inspection of the low‐frequency region by the baseline corrected spectra and the second derivative spectra shows that the broad feature consists of a major band at around 185 cm−1 and a weak shoulder at around 150 cm−1. We have assigned these two peaks at 185 and 150 cm−1 to the structured and destructured water, respectively, based on the results of 2D‐COS and the comparison with the results of multivariate curve resolution‐alternative least squares reported by Hamaguchi et al. A hetero 2D correlation synchronous map between the 3750–3000 and 400–100 cm−1 regions reveals that there is a cross peak between the structured water band at around 3200 cm−1 and the 185 cm−1 band, confirming that the 185 cm−1 band comes from the structured water.Wiley, Sep. 2022, Journal of Raman Spectroscopy, 53(10) (10), 1669 - 1678, English[Refereed]Scientific journal
- Semi-clathrate hydrates are attractive heat storage materials because the equilibrium temperatures, located above 0 °C in most cases, can be changed by selecting guest cations and anions. The equilibrium temperatures are influenced by the size and hydrophilicity of guest ions, hydration number, crystal structure, and so on. This indicates that intermolecular and/or interionic interaction in the semi-clathrate hydrates may be related to the variation of the equilibrium temperatures. Therefore, intermolecular and/or interionic interaction in semi-clathrate hydrates with quaternary onium salts was directly observed using low-frequency Raman spectroscopy, a type of terahertz spectroscopy. The results show that Raman peak positions were mostly correlated with the equilibrium temperatures: in the semi-clathrate hydrates with higher equilibrium temperatures, Raman peaks around 65 cm-1 appeared at a higher wavenumber and the other Raman peaks at around 200 cm-1 appeared at a lower wavenumber. Low-frequency Raman observation is a valuable tool with which to study the equilibrium temperatures in semi-clathrate hydrates.Jul. 2022, Molecules (Basel, Switzerland), 27(15) (15), English[Refereed]Scientific journal
- Corresponding, Elsevier BV, May 2022, Polymer, 248, 124820 - 124820, English[Refereed]Scientific journal
- Inter- and intramolecular hydrogen bonding and their temperature-dependent changes in a poly(4-vinylphenol)/poly(methyl methacrylate)(PVPh 30%/PMMA 70%) blend were investigated using near-infrared (NIR) and infrared (IR) spectroscopy. Band assignments of the fundamentals and first overtones of the OH stretching mode of a free OH group and OH groups in C=O···HO and OH···OH (dimer, trimer, and oligomer) hydrogen bonding of PVPh 30%/PMMA 70% were carried out by comparison between its NIR and IR spectra and comparison with NIR and IR spectra of phenol. The comparison of the NIR spectra of the PVPh 30%/PMMA 70% blend (hereafter, we denote it as PVPh30%) with the corresponding IR spectra reveals that to observe bands arising from the free OH and OH···OH dimer, which is a weaker hydrogen bonding, NIR is better while to investigate bands originating from OH groups in the OH···O=C and OH···OH (oligomer) hydrogen bonds, which are stronger hydrogen bonding, IR is better. Thus, a combination of IR and NIR spectroscopy has provided convincing results for the hydrogen bonding of PVPh30%. The relative intensity of the two bands at 7058 and 6921 cm–1 (I7058/I6921) due to the first overtones of the OH stretching modes of the free OH group and the OH group in the dimer, respectively, increases significantly above 90 °C, which is close to Tg of PVPh. In concomitance with the intensity increase in the relative intensity of the free OH band, the intensity of a band at 1706 cm–1 due to the C=O stretching mode of the C=O···HO hydrogen bond of PVPh30% decreases above 90°C. These results suggest that above the Tg of PVPh the C=O···HO hydrogen bond is broken gradually and that the free OH increases. Of note is that below Tg the intensities of NIR bands due to the OH first overtones of free OH group and OH groups in the OH···OH dimer gain intensity in parallel with temperature increase, and above Tg the intensity of the band derived from the OH···OH group increases linearly much slower than that of the band due to the free OH. Moreover, a band due to an OH···OH oligomer decreases linearly. Hence, it is very likely that the OH···OH oligomers dissociate into free OH groups. Anharmonicity of O–H bonds, which is sensitive to a hydrogen bond, was estimated for the free OH and OH bonds in the C=O···HO and OH···OH (dimer, trimer, and oligomer) hydrogen bonding by comparison between the NIR and IR spectra in the OH stretching band regions.Lead, SAGE Publications, Apr. 2022, Applied Spectroscopy, 000370282210869 - 000370282210869, English[Refereed]Scientific journal
- Elsevier BV, Apr. 2022, Polymer, 246, 124725 - 124725, English[Refereed]Scientific journal
- Elsevier BV, Nov. 2021, Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, 260, 119900 - 119900[Refereed]Scientific journal
- Elsevier BV, Sep. 2021, Polymer, 230, 124103 - 124103[Refereed]Scientific journal
- Near-infrared spectroscopy (NIR) and DFT calculations were applied to study solvent effect on competition between weak and strong interactions in phenol solutions.Royal Society of Chemistry (RSC), Aug. 2021, Physical Chemistry Chemical Physics, 23(35) (35), 19188 - 19194, English[Refereed]Scientific journal
- American Chemical Society (ACS), Jul. 2021, Macromolecules, 54(13) (13), 6440 - 6448[Refereed]Scientific journal
- In this study, we explored the electronic structure of the surfaces of polyethylene samples having different crystallinities using attenuated total reflection (ATR) far-ultraviolet (FUV) spectroscopy and quantum chemical calculations. Specifically, the ATR-FUV spectra of five types of high-density polyethylene (HDPE), six types of linear low-density PE (LLDPE), and seven types of low-density PE (LDPE) were obtained. All the spectra contained an intense band near 156 nm and a broad band between 180 and 190 nm. Transmission spectra were obtained for the thin-film (30 µm) PE samples between 165 and 250 nm. In this region, the HDPE films show very low-intensity bands. In contrast, the transmission spectra of the LLDPE and LDPE samples yielded weak-to-medium and medium-intensity bands around 180-190 nm, respectively. In addition, to understand the differences in the absorption spectra among the PEs observed, we simulated the spectra of n-pentane as a PE crystal model using time-dependent density functional theory and found that the common intense band at 156 nm is due to the σ (C(2p)-H)→Rydberg 3s, 3p transition. The absorption bands near 180-190 nm may correspond to aggregates of numerous molecular chains in the amorphous parts of the LLDPE and LDPE samples.Last, May 2021, Applied spectroscopy, 37028211013425 - 37028211013425, English, International magazine[Refereed]Scientific journal
- Inter- and intramolecular interactions in multicomponent polymer systems influence their physical and chemical properties significantly and thus have implications on their synthesis and processing. In the present study, chemical images were obtained by plotting the peak position of a spectral band from the data sets generated using in situ attenuated total reflection Fourier transform infrared (ATR FT-IR) spectroscopic imaging. This approach was successfully used to visualize changes in intra- and intermolecular interactions in poly(3-hydroxybutyrate)/poly(L-lactic acid) (PHB/PLLA) blends during the isothermal melt crystallization. The peak position of ν(C=O) band, which reflects the nature of the intermolecular interaction, shows that the intermolecular interactions between PHB and PLLA in the miscible state (1733 cm−1) changes to the inter- and intramolecular interaction (CH3⋯O=C, 1720 cm−1) within PHB crystal during the isothermal melt crystallization. Compared with spectroscopic images obtained by plotting the distribution of absorbance of spectral bands, which reveals the spatial distribution of blend components, the approach of plotting the peak position of a spectral band reflects the spatial distribution of different intra- and intermolecular interactions. With the process of isothermal melt-crystallization, the disappearance of the intermolecular interaction between PHB and PLLA and the appearance of the inter- and intramolecular interactions within the PHB crystal were both visualized through the images based on the observation of the band position. This work shows the potential of using in-situ ATR FT-IR spectroscopic imaging to visualize different types of inter- or intramolecular interactions between polymer molecules or between polymer and other additives in various types of multicomponent polymer systems.Corresponding, SAGE Publications, Apr. 2021, Applied Spectroscopy, 000370282110102 - 000370282110102[Refereed]Scientific journal
- Corresponding, Elsevier BV, Apr. 2021, Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, 250, 119305 - 119305[Refereed]Scientific journal
- © Herein, differences in the intermolecular interactions and flexibility between poly(ethylene terephthalate) (PET) and poly(butylene terephthalate) (PBT) are studied by far-infrared, terahertz (THz), and low-frequency Raman spectroscopy and quantum chemical calculations (QCCs). Interatomic distance calculations based on the reported crystal structures and natural bond orbital analysis indicate that PBT exhibits intermolecular hydrogen bonding between a C=O group and a CH2 group in the adjacent molecular chains, while PET does not have such hydrogen bonding. The results of infrared measurements also suggest that the C=O and CH2 groups of PBT are involved in intermolecular hydrogen bonding. Both PET and PBT show a THz band at around 113 cm-1 and a Raman band at around 111 cm-1. These bands indicate different thermal behaviors of PET and PBT. The results of QCCs performed using the Cartesian coordinate tensor transfer method suggest that these bands of PBT include the CH2 bending mode, while those of PET have only a small contribution from the corresponding mode. These differences in the thermal behavior and vibrational modes of the 113 cm-1 bands can be possibly attributed to the difference in flexibility between PET and PBT due to the different number of CH2 groups. In addition, these bands of PBT seem to reflect the intermolecular C=O···H-C hydrogen bonding. Therefore, it may be concluded that the difference in the number of CH2 groups causes the difference in the flexibility of the molecular chains between PBT and PET and the existence or non-existence of intermolecular C=O···H-C hydrogen bonding. It is worth noting that THz and low-frequency Raman spectroscopy can clearly reveal the difference in flexibility. It is also very likely that both the flexibility of the molecular chains and the intermolecular hydrogen bonding affect the difference in the crystallization rate between PET and PBT.Corresponding, Jan. 2021, Macromolecules, 54(542) (542), 1052 - 1062[Refereed]Scientific journal
- © 2020 American Chemical Society. The detection of phase separation and crystallization in biopolymer blends is an important aspect of biopolymer processing. In this study, attenuated total reflection (ATR)-Fourier transform infrared (FTIR) spectroscopic imaging has been applied to visualize the crystallization and phase separation of a poly(3-hydroxybutyrate) (PHB)/poly(L-lactic acid) (PLLA) blend simultaneously in situ. The peak shift of the ν(C=O) band of PHB during the isothermal crystallization process revealed a transformation of the intermolecular interaction between PHB and PLLA in the miscible state to the inter- and intramolecular interactions between PHBs in the immiscible state. The appearance and gradual separation of crystalline PHB-rich domains and crystalline PLLA-rich domains in the acquired ATR-FTIR spectroscopic images clearly showed the whole dynamic process of phase separation. With increasing isothermal crystallization time, the larger size of crystalline polymer-rich domains and the increasing integrated absorbance of the ν(C=O) band of crystalline polymers both revealed the increasing degree of crystallization in the polymer blend, which is constant with the isothermal crystallization process of pure polymers. The extent of phase separation between crystalline PHB-rich domains and crystalline PLLA-rich domains is enhanced with increasing isothermal crystallization temperature. This is because the higher isothermal crystallization temperature slows down the crystallization, which leaves more time for phase separation. The degree of crystallization in the blend decreased with increasing isothermal crystallization temperature, which was also constant with the isothermal crystallization process of the pure polymers. Finally, a new proposal for the mechanism of phase separation and crystallization in the polymer blend has been discussed. It was found that decreasing the isothermal crystallization temperature is an effective method to restrict the phase separation and control the final morphology in the upper critical solution temperature (UCST) crystallizable polymer blend.Corresponding, Oct. 2020, Macromolecules, 53(20) (20), 9074 - 9085[Refereed]Scientific journal
- © Published under licence by IOP Publishing Ltd. Biodegradable polymer is preferred material to replace the conventional petroleum based polymer materials to protect the nature and conserve oil supplies. Information related to higher-order structure and hydrogen bonding among polymers can be observed in the low-frequency region (3.3-333 cm-1) using terahertz (THz) spectroscopy. THz spectra measurement of temperature-dependent investigation of poly(3-hydroxybutyrate) (PHB) homopolymer and polymer blend of PHB/glycol chitosan with the blend ratios of (80/20) and (60/40) have been performed to investigate the change in higher-order structure and intermolecular hydrogen bonding formed by polymer blends of PHB and glycol chitosan. The THz spectra revealed that the peak at 82 cm-1 does not collapse even in the high temperature indicating the important role of hydrogen bonding interaction between poly(3-hydroxybutyrate) (PHB) and glycol chitosan in maintaining the higher-order structure of the PHB in its blending system.Corresponding, May 2020, IOP Conference Series: Materials Science and Engineering, 835(1) (1)[Refereed]International conference proceedings
- Copyright © 2020 American Chemical Society. Polymer nanoparticles (NPs) can be highly attractive in numerous applications, including biomedicine, where the use of inorganic matter may be detrimental for living tissues. In conventional wet chemistry, polymerization and functionalization of NPs with specific chemical groups involves complex and often numerous reactions. Here, we report on a solvent-free, single-step, low-temperature plasma-based synthesis of carboxylated NPs produced by the polymerization of acrylic acid under the conditions of a glow discharge. In a monomer-deficient regime, the strong fragmentation of monomer molecules by electron impact results in the formation of 15 nm-sized NPs with <1% retention of the carboxyl groups. In an energy-deficient regime, larger 90 nm-sized NPs are formed with better retention of carboxyl groups that reaches 16%. All types of NPs exhibit a glass transition above room temperature, which makes them highly stable in an aqueous environment with no dissolution or swelling. The NPs are also found to degrade thermally when heated above 150 °C, with a decrease in the mean NP size but with retention of the chemical composition. Thus, plasma polymerization proves to be a versatile approach for the production of polymer NPs with a tunable size distribution, chemical composition, and physical properties.Jan. 2020, Journal of Physical Chemistry B, 124(4) (4), 668 - 678[Refereed]Scientific journal
- © 2020 The Japan Society for Analytical Chemistry. An intensive analysis of far-infrared (far-IR), low-frequency Raman, and wide angle X-ray diffraction (WAXD) data has been performed by two-dimensional correlation spectroscopy (2D-C0S) as a function of the blend ratio of poly(3-hydro\ybutyrate)/poly(4-vinylphenol) (PHB/PVPh). Honiospectral 2D-C0S revealed that a weak band at 128 cm-1 in the far-IR spectra appeared more clearly in the 2D correlation spectra. Heterospectral 2D-C0S (far-IR/Iow-frequency Raman and far-IRAVAXD) provided very important results that were hardly detected in the conventional 2D-COS. A far-IR peak at 130 cm-1 in the heterospectral 2D-COS had negative correlations with the peaks in the low-frequency Raman spectra at 81, 100, and 110 cm-1 and \\v\XD profile 8.78 and 11.01°. These results indicated that those peaks have different origins; the 130 cm-1 peak comes from the intermolecular C=0-H-0 hydrogen bond between PHB and PVPh, while those for low-frequency Raman and WAXD peaks are the features of PHB crystalline structure.Corresponding, 2020, Analytical Sciences, 36(6) (6), 731 - 737[Refereed]Scientific journal
- Copyright © 2019 American Chemical Society. This study investigates the electronic transitions of complexes of lithium with polyethylene glycol (PEG) by the absorption bands of solvent molecules via attenuated total reflectance spectroscopy in the far-UV region (ATR-FUV). Alkali-metal complexes are interesting materials because of their functional characteristics such as good ionic conductivity. These complexes are used as polymer electrolytes for Li batteries and as one of the new types of room-temperature ionic liquids, termed solvation ionic liquids. Considering these applications, alkali-metal complexes have been studied mainly for their electrochemical characteristics; there is no fundamental study providing a clear understanding of electronic states in terms of electronic structures for the ground and excitation states near the highest occupied molecular orbital-lowest occupied molecular orbital transitions. This study explores the electronic transitions of ligand molecules in alkali-metal complexes. In the ATR-FUV spectra of the Li-PEG complex, a decrease in intensity and a large blue shift (over 4 nm) were observed to result from an increase in the concentration of Li salts. This observation suggests the formation of a complex, with coordinate bonding between Li+ and the O atoms in PEG. Comparison of the experimental spectrum with a simulated spectrum of the Li-PEG complex calculated by time-dependent density functional theory indicated that changes in the intensities and peak positions of bands at approximately 155 and 177 nm (pure PEG shows bands at 155, 163, and 177 nm) are due to the formation of coordinate bonding between Li+ and the O atoms in the ether molecule. The intensity of the 177 nm band depends on the number of residual free O atoms in the ether, and the peak wavelength at approximately 177 nm changes with the expansion of the electron clouds of PEG. We assign a band in the 145-155 nm region to the alkali-metal complex because we observed a new band at approximately 150 nm in the ATR-FUV spectra of very highly concentrated binary mixtures.AMER CHEMICAL SOC, Dec. 2019, Journal of Physical Chemistry A, 123(50) (50), 10746 - 10756, English[Refereed]Scientific journal
- © 2019 Elsevier Ltd Composition- and temperature-dependent far-infrared (FIR), terahertz (THz), and low-frequency Raman spectra of poly(3-hydroxybutyrate) (PHB)/Poly(4-vinylphenol) (PVPh) polymer blends were measured to investigate the effects of PVPh in PHB crystallization. FIR, low-frequency Raman, and wide angle X-ray diffraction (WAXD) studies revealed that PVPh reduces the crystallinity of PHB in blends without a significant change in the crystal structure. The FIR and low-frequency Raman spectra divided the blends into three categories: high-ordered crystalline, less-ordered crystalline, and amorphous. A new peak was observed at 135 cm−1 in the FIR spectra of the PHB/PVPh blends, which may be assigned to the less-ordered crystalline phase of PHB, predicting the inter-molecular hydrogen-bond interactions of PHB/PVPh. The intensity ratio of the peaks at 97 and 82 cm−1 changed with the blending ratio variations owing to the crystalline dynamics of PHB. Deformation of the PHB helical structure occurred first, followed by weakening of the intra-molecular hydrogen-bond within PHB. Shifts of several peaks were observed in the FIR and low-frequency Raman spectra, suggesting that the intra-molecular hydrogen-bond (C[dbnd]O⋯H-C-) within PHB weakened with temperature. The novelty of the present study is to demonstrate that low-frequency vibrational spectroscopy is very sensitive to monitor changes from the intra-molecular hydrogen bonding to inter-molecular hydrogen bonding between PHB and PVPh.ELSEVIER SCI LTD, Oct. 2019, Polymer, 181, English[Refereed]Scientific journal
- © 2019 Wiley Periodicals, Inc. Poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH) is a biodegradable and highly flexible polymer, which should have various applications like inflation film, T die extruded films and sheets, injection-molded and blow-molded articles, etc. Despite its attractive features, it suffers from the limitation of slow crystallization during molding, and none of the numerous nucleating agents examined to resolve this issue has yet proven successful. The addition of a higher-melting biodegradable polyester is reported to be an effective solution, with the residual crystals preserved during PHBH melting being important for subsequent crystallization. However, this phenomenon is only observed under static conditions, for example, during differential scanning calorimetry and spectroscopic analysis using a variable temperature cell. In this study, the relationship between the amount of residual crystals and the subsequent crystal behavior was investigated under dynamic conditions, such as practical extrusion molding. Online near-infrared spectroscopy was used to analyze the residual amount of crystals at the extruder outlet and explore the crystallization behavior of the extruded strands in real time. Even under the dynamic conditions, a close relationship was found between the amount of residual crystals and the subsequent crystallization behavior. In addition, the Avrami exponent (n) and the crystallization rate constant (k) were analyzed.Aug. 2019, Polymer Crystallization, 2(4) (4)[Refereed]Scientific journal
- © 2019 American Chemical Society. Far-infrared (FIR) and low-frequency Raman bands in the 90-400 cm1 region of crystalline nylon 6 in-form were assigned based on comparisons of experimental spectra and quantum mechanical calculations. A fragment methodology was applied in the calculations for explicit consideration of interchain interactions and crystal symmetry. The main features in both Raman and FIR spectra were reproduced well, which enabled the band assignments based on density functional theory and the significant improvement of the conventional assignments for which there had been a big dispute. Temperature dependence of the experimental FIR spectra has revealed that both bands at 222 and 111 cm1 are characteristic of the α-form structure. Their intensities linearly decreased with increasing temperature with marked two transition points, which correspond to glass and Brill transitions. Both bands can be indicators of the lattice length of α-form nylon 6. On the basis of the calculations, the FIR and Raman bands at ∼100 cm1 were successfully assigned to methylene torsion and transverse motion of amide groups in which NH and O atoms move out of the amide plane. Decomposition of the calculated spectra revealed that the intensities at ∼100 cm1 in both spectra mainly originate from the amide groups and only secondarily from the methylene groups. Moreover, the FIR intensities at ∼100 cm1 were nearly perfectly governed by the amide groups, which could be a reason why this FIR band is particularly sensitive to hydrogen bonds among the low-frequency bands. The FIR band at 222 cm1 was assigned to methylene torsion and transverse motion of NH groups. Both FIR bands at 222 and 111 cm1 contain perpendicular motions of methylene and amide groups. This will be a reason for their sensitivity to interchain interactions in α-form nylon 6. Contrarily, the FIR band at 294 cm1 is in parallel polarization to the chain direction and assigned to a deformation of C-CH2-CH2 and bending motion of C-O in the amide plane. This is the reason why this band is not sensitive to the structural transitions of nylon 6. Our previous works revealed that in regions of 125 and 70 cm1, there are specific vibrational peaks of crystalline polyesters primarily arising from out-of-plane motion of ester groups. We can find a similarity in 125 and 70 cm1 regions between crystalline polyesters and nylon 6 that both polymers show specific out-of-plane vibrational peaks around 100 cm1, which are sensitive to the lattice length among polymer chains.AMER CHEMICAL SOC, Jun. 2019, Journal of Physical Chemistry B, 123(25) (25), 5368 - 5376, English[Refereed]Scientific journal
- © 2019 Elsevier Ltd In the present study, isothermal crystallization of asymmetric PLLA/PDLA blend (4/1) at around 100 °C was investigated by in-situ time-resolved FTIR and Raman Imaging measurement. FTIR result indicated that crystallization of homo-crystal (HC) was retarded due to the formation of large amount of stereocomplex (SC) in the isothermal process. A unique spherulite morphology was observed through polarized optical microscopy (POM) and the distribution of SC and HC in and out of the big spherulite was revealed under the assistance of Raman imaging measurement. These results demonstrated that the SC crystal dispersed homogeneously both in the amorphous and spherulite region. However, the HC mainly located in the big spherulite area. A possible isothermal crystallization process for the asymmetric PLLA/PDLA blend was proposed.May 2019, Polymer, 172(20) (20), 1 - 6, English[Refereed]Scientific journal
- © 2018, The Society of Polymer Science, Japan. Isothermal crystallization of poly(glycolic acid) (PGA) has been studied using terahertz (THz) and infrared (IR) spectroscopy and simultaneous small-angle X-ray scattering (SAXS)/wide-angle X-ray diffraction (WAXD) measurements. Changes in the intermolecular interactions in PGA during the isothermal crystallization were monitored using THz spectroscopy, which is an efficient technique for analyzing the higher-order structure of polymers. In the THz spectra, the temporal difference in the intensity observed in the isothermal crystallization is due to the difference in the vibrational origins of two bands at 192 and 65 cm−1. The band at 192 cm−1 primarily originates from the intramolecular vibrational mode (twisting of the local structure of the PGA molecular chain). Furthermore, the band at 65 cm−1 exists due to the intermolecular vibration mode (C = O···H-C hydrogen bonds between polymer chains). In addition, these THz bands appeared after the appearance of the SAXS and WAXD peaks. When a lamellar structure is formed and the molecular chains are oriented, the THz band originating from the intermolecular vibration is observed. It is highly possible that the intermolecular vibration appearing in the THz spectra requires the molecular chains to be oriented.Corresponding, NATURE PUBLISHING GROUP, Feb. 2019, Polymer Journal, 51(2) (2), 237 - 245, English[Refereed]Scientific journal
- © 2018 Wiley Periodicals, Inc. Proton dynamics of hydrogen bonds (HBs) in the α and γ form of Nylon 6 were investigated by Born–Oppenheimer molecular dynamics (BOMD). Our results show differences in the dynamic effects of interchain HB interactions between the α form and the γ form of Nylon 6. Analysis of the time course of the geometrical parameters of HBs along the BOMD simulations has shown that HBs are dynamically favored in the γ form of Nylon. The quantization of the NH stretching mode enables a detailed discussion of the strengths of HB interactions. Solving the Schrödinger equation for the snapshots of one-dimensional proton potentials, extracted from the ab initio MD, enables the consideration of anharmonicity, thermodynamics, and approximate quantum effects on proton movement. A larger red shift of the NH stretching band was observed in the γ form compared with the α form. Our study shows that HBs are more stabilized in the γ form than in the α form, which is mainly due to the higher number of HBs. The distribution of HBs along the trajectory clearly reveals the preference of the γ form. The quantization of the NH motion enables the discussion of the differences in the IR spectra between the two forms.Jul. 2018, International Journal of Quantum Chemistry, 118(14) (14), e25595, English[Refereed]Scientific journal
- © 2018 Elsevier B.V. We measured terahertz (THz) and low-frequency Raman spectra of Poly (butylene succinate) (PBS) which shows the crystal transition from α to β by stretching. For the assignment of the absorption peaks in the low-frequency region, we performed quantum chemical calculations with Cartesian-coordinate tensor transfer (CCT) method. Four major peaks appeared in the THz spectra of PBS at around 58, 76, 90, and 100 cm−1, and in the low-frequency Raman spectra a peak was observed at 88 cm−1. The THz peak at 100 cm−1 and the Raman peak at 88 cm−1 show a shift to a lower wavenumber region with increasing temperature. The quantum chemical calculation of β crystal form reveals the new peak appears above 100 cm−1. It was found that two kinds of peaks overlapped at around 100 cm−1 in the THz spectra of PBS. One of them can be assigned to a weak hydrogen bond between the C=O and CH2 groups in the intermolecular chains, which is perpendicular to the molecular chain of the α crystal form. Another one showed a parallel polarization which can be assigned to the intramolecular interaction between O (ether) and H-C groups in the β crystal form. The position of the peak at around 100 cm−1 in the perpendicular polarization changed to a lower wavenumber region with stretching, because of the weakening of the intermolecular hydrogen bonding by increasing the interatomic distances. On the other hand, that of the parallel polarization shifts to a higher wavenumber region because of the shortening of the interatomic distance from α to β crystal form (the strength of the intramolecular hydrogen bonding became stronger) by stretching.Elsevier B.V., May 2018, Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy, 197(197) (197), 95 - 102, English[Refereed]Scientific journal
- © 2018 Elsevier Ltd The long range structure of poly(ε-caprolactone) (PCL) has been studied by terahertz (THz) spectroscopy, infrared (IR) spectroscopy and quantum chemical calculations (QCCs). Natural bond orbital (NBO) analysis and the calculation of the interatomic distances between C-H and O=C groups in PCL crystalline indicate that the PCL chain has three kinds of weak intermolecular interactions between the CH2 and C=O groups. In the IR spectra, significant changes due to the influence of hydrogen bondings were observed in the CH2 and C=O stretching vibration regions. The results of QCCs performed by using the Cartesian Coordinate Tensor Transfer (CCT) method to assign the THz spectra of PCL suggest that the peaks at 47 and 67 cm−1 reflect the atomic motions of the C=O + CH2 moiety derived from the weak C-H⋯O=C hydrogen bondings. THz spectroscopy allows us to observe the intermolecular hydrogen bondings of the polymer separately, since hydrogen bondings with different strengths yield different peaks in a THz spectrum. The results of THz and IR spectral analysis, and QCCs all indicate that PCL forms three kinds of weak intermolecular C-H⋯O=C hydrogen bondings between the CH2 and C=O groups. This may be one of the causes for the low melting temperature but high crystallinity of PCL. There are about six interactions in PCL and about sixteen interactions in polyglycolic acid (PGA), within the lamellar thickness. Therefore, it is suggested that the difference in the number of intermolecular interactions within the lamellar thickness leads to the difference in melting points between the two polymers.ELSEVIER SCI LTD, Feb. 2018, Polymer, 137, 245 - 254, English[Refereed]Scientific journal
- © 2017 Elsevier Ltd The phase separation of poly(methyl methacrylate) (PMMA)/poly(4-vinyl phenol) (PVPh) (50/50 wt%) ultra-thin films was investigated by infrared reflection absorption spectroscopy (IR-RAS). Of particular note is that we succeeded in measuring the IR-RAS spectra of ultra-thin films of PMMA/PVPh (50/50 wt%) polymer blend with a film thickness of only 2.14 nm. It was found from the present study that the PMMA/PVPh polymer blends were clearly separated as the film thickness was thinner than the radius of gyration of PMMA. The IR-RAS spectra reveal that the hydrogen bond between the C=O group of PMMA and the OH group of PVPh is broken upon the phase separation in the ultra-thin film. In the spectra, many peaks are observed in the OH stretching region of the ultra-thin PMMA/PVPh films, indicating the existence of several weak hydrogen bonds with slightly different interactions, presumably due to the quasi-stable molecular chain configurations resulting from the strong confinement. This is in sharp contrast to the corresponding bulk sample for which a broad band is usually observed in this region because of the continuous distribution of the hydrogen bonding, which is typical for the blends.ELSEVIER SCI LTD, Jan. 2018, Polymer, 135, 69 - 75, English[Refereed]Scientific journal
- © 2017 Elsevier Ltd Composition-, temperature-, and polarization-dependent low-frequency Raman and terahertz (far-infrared; FIR) spectra were measured for poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (P(HB-co-HV)) with PHB-type crystal structure and PHV-type crystal structure to investigate their intermolecular interactions. Band assignments were attempted by comparing the low-frequency Raman and terahertz (FIR) spectra of P(HB-co-HV) with the varying HV content with the corresponding spectra of PHB and by observing spectral variations. The spectra of P(HB-co-HV) (HV = 9, 15, and 21 mol%) are similar to the corresponding spectra of PHB. There are two bands at 97 and 82 cm−1 which are assigned to a spring type vibrational mode of the helical structure and to the mode reflecting the intermolecular interaction (CH3⋯O=C hydrogen bond), respectively. The low-frequency Raman and terahertz spectra of P(HB-co-HV) with HV content of 66 and 88.6 mol% show bands at 91 and 78 cm−1. The 78 cm−1 band is assigned to the intermolecular interaction (CH2⋯O=C hydrogen bond). In contrast to the 97 cm−1 band of P(HB-co-HV) with the low HV content, the 91 cm−1 band of P(HB-co-HV) with the high HV content show a temperature-dependent shift by 4 cm−1. Thus, although it seems that both 97 and 91 cm−1 bands are due to spring-like vibrational modes, the nature of two vibrational modes seems to be significantly different, reflecting the difference in the intermolecular interaction.Elsevier Ltd, Jan. 2018, Polymer, 135(135) (135), 331 - 337, English[Refereed]Scientific journal
- © 2018 the Owner Societies. We investigated the surface (<50 nm) of poly(3-hydroxybutyrate) (PHB) and its nanocomposite with graphene by attenuated total reflection far- and deep-ultraviolet (ATR-FUV-DUV; 145-300 nm; 8.55-4.13 eV) spectroscopy and quantum mechanical calculations. The major absorption of polymers occurs in FUV and is related to Rydberg transitions. ATR-FUV-DUV spectroscopy allows for direct measurements of these transitions in the solid phase. Using ATR-FUV-DUV spectroscopy, periodic density functional theory (DFT) and time-dependent DFT (TD-DFT), we explained the origins of the FUV-DUV absorption of PHB and provided insights into structural changes of PHB which occur upon formation of a graphene nanocomposite and upon heating of the pure polymer. The structural changes cause specific and gradual spectral variations in FUV-DUV. We systematically studied the relaxation of the polymer helix and concluded that the common feature of all models of the unfolded helix lies in a specific and consistent FUV-DUV spectral signature. Relaxed structures feature a blue-shift of the major FUV transition (non-bonding molecular orbital to Rydberg 3p and π to π∗) as compared with crystalline PHB. The FUV absorption of the relaxed structures was determined to be significantly stronger than that of the crystalline state. These results are consistent with the observed temperature-dependent spectra of the pure PHB. The simulation of the thermal expansion of the crystalline polymer by a periodic-DFT study allows us to exclude the possibility that spectral variations observed experimentally are influenced by changes in the crystalline phase. We concluded that the crystallinity of PHB at the sample surface increases with an increase in graphene content in the nanocomposite. However, it is unlikely that the polymer structure inside the crystal is affected; instead the FUV-DUV spectral variations result from changes in the polymer morphology that occur at the sample surface. The phase transition of PHB is affected by temperature and addition of graphene content. These changes are likely to be the opposite of those occurring in the bulk sample.ROYAL SOC CHEMISTRY, 2018, Physical Chemistry Chemical Physics, 20(13) (13), 8859 - 8873, English[Refereed]Scientific journal
- © 2017 American Chemical Society. We report a correlation between the dielectric property and structure of stretched poly(lactic acid) (PLA) films, revealed by polarization-sensitive terahertz time-domain spectroscopy and two-dimensional (2D) wide-angle X-ray scattering (WAXS). The experiments evidence that the dielectric function of the PLA film becomes more anisotropic with increasing draw ratio (DR). This behavior is explained by a classical Lorentz oscillator model assuming polarization-dependent absorption. The birefringence can be systematically altered from 0 to 0.13 by controlling DR. The combination of terahertz spectroscopy and 2D WAXS measurement reveals a clear correlation between the birefringence in the terahertz frequency domain and the degree of orientation of the PLA molecular chains. These findings imply that the birefringence is a result of the orientation of the PLA chains with anisotropic macromolecular vibration modes. Because of a good controllability of the birefringence, polymer-based materials will provide an attractive materials system for phase retarders in the terahertz frequency range.AMER CHEMICAL SOC, Jul. 2017, Journal of Physical Chemistry B, 121(28) (28), 6951 - 6957, English[Refereed]Scientific journal
- © 2017, © The Author(s) 2017. The distribution of crystallinity and the crystalline orientation of a poly(ɛ-caprolactone) (PCL) film have been studied using terahertz (THz) imaging. Terahertz images were developed by using the intensity ratio of the two spectral eaks at 1.42 and 2.03 THz that are assigned to the crystalline modes parallel and perpendicular to the c-axis (I⊥/I || ) of the PCL film. The obtained THz images show that the distribution of crystallinity and crystalline orientation vary considerably between the different regions in the PCL film, even though this inhomogeneity is not visible in the corresponding optical image. Our results clearly illustrate that THz imaging is a promising technique to characterize the physical properties of semi-crystalline polymers.SAGE PUBLICATIONS INC, Jul. 2017, Applied Spectroscopy, 71(7) (7), 1537 - 1542, English[Refereed]Scientific journal
- In this letter we present results of study of weak C-H center dot center dot center dot O=C hydrogen bonds of crystalline poly-(R)-3-hydroxybutyrate (PHB) by using Born-Oppenheimer molecular dynamics. The-polymeric structure and IR spectra of PHB result from the presence of the weak hydrogen bonds. We applied the post-molecular dynamics analysis to consider a C=O motion as indirectly involved in the hydrogen bonds. Quantization of the nuclear motion of the oxygens was,done to perform detailed analysis of the strength and properties of the C=O bands involved in the weak hydrogen bonds. We have also shown the dynamic character of the weak hydrogen bond interactions. (C) 2017 Elsevier B.V. All rights reserved.ELSEVIER SCIENCE BV, Jun. 2017, CHEMICAL PHYSICS LETTERS, 678(678) (678), 112 - 118, English[Refereed]Scientific journal
- Poly(butylene adipate) (PBA), an important biodegradable polymer, can crystallize into a particular type of ring banded spherulite, in each of which two crystal forms, alpha and beta, coexist. However, the distribution of the polymorphic crystals and the molecular chains orientation within the ring-banded PBA spherulites are still unclear. To determine these, in our present study, Raman spectroscopy and high spatial resolution Raman imaging were used. Characteristic Raman peaks were identified for both the alpha- and beta-forms and for amorphous structures. Using these peaks, we investigated the polymorphic crystal distribution and molecular chain orientation within the spherulites through Raman imaging. The two crystal forms are found to be unevenly distributed in the center, ring-banded, and out-layer ringless region. The results of this study also suggested that the two crystal forms can nucleate and grow in the same temperature range (31-33 degrees C), but the relative content of the alpha-form in the ring banded region becomes higher with the higher crystallization temperature. The image based on the Hermans orientation function for the ring-banded spherulite shows both bow-tie and ring-banded patterns, which means that the molecular chains in the ring-banded region orient not only about the radial direction of the spherulites but also about the substrate plane. Moreover, the molecular chain orientations also show periodically change along the radial direction of the ring-banded spherulite. The present study shows that Raman imaging is a very powerful technique in polymer crystal structure research.AMER CHEMICAL SOC, Apr. 2017, MACROMOLECULES, 50(8) (8), 3377 - 3387, English[Refereed]Scientific journal
- Low-frequency vibrational modes of lamellar crystalline poly(glycolic acid) (PGA) were measured on Raman and far-infrared (FIR) spectra. Among the observed bands, an FIR band at similar to 70 cm(-1) and a Raman band at 125 cm(-1) showed a gradual lower-frequency shift with increasing temperature from 20 degrees C to the melting point at similar to 230 degrees C. Their polarization direction was perpendicular to the chain axis of PGA. Both spectra were quantum-mechanically simulated with the aid of a fragment method, the Cartesian-coordinate tensor transfer, which enabled an explicit consideration of molecular interactions between two adjacent polymer chains. Good agreement was achieved between the experiment and theory in both spectra. The temperature-sensitive bands at similar to 70 cm(-1) in FIR and at 125 cm(-1) in Raman comprise the out-of-plane C=O bending motion. The temperature-dependent shifts of the low-frequency bands were successfully simulated by the DFT-spectral calculation, exploring that the main origin of the shifts is the thermal expansion of the crystal lattice. This result indicates that the thermally shifted bands may be used as an indicator of the lattice expansion of PGA. Possible changes in intermolecular interactions of PGA under temperature rising were ascribed on the basis of natural bond,orbital theory. The steric repulsion between the carbonyl O atom in one chain and the H-C bond in the adjacent chain will be a dominant interaction in the lattice-expanding process, which would cause the observed thermal shifts of the bending modes. Comparisons of the spectral assignment for PGA obtained in this study and that for poly-(R)-3-hydroxybutyrate (PHB) reported by us suggest that crystalline polyesters give vibrational modes composed of out-of-plane bending motion of C=O groups between similar to 70 and similar to 125 cm(-1), the modes of which are sensitive to the thermal expansion of crystal lattice and its concomitant changes in their intermolecular interactions.AMER CHEMICAL SOC, Feb. 2017, JOURNAL OF PHYSICAL CHEMISTRY B, 121(5) (5), 1128 - 1138, English[Refereed]Scientific journal
- The crystallization behavior and crystalline structures of poly(3-hydroxybutyrate) (PHB) ultrathin films similar to 52 nm) under spatial confinement were investigated using infrared reflection absorption-spectroscopy (IR-RAS) and two-dimensional grazing incidence X-ray diffraction (2DGIXD). Intermediate and highly ordered crystalline states were observed during heating and melt -cooling of these films. In the ultrathin films, the intermediate state was noticeably stable at lower temperatures, whereas the highly ordered state was more stable at higher temperatures. A transformation from the intermediate state into the highly ordered state occurred as the temperature increased, as the crystals in the intermediate state acquire sufficient thermal energy to overcome the energy barrier. 2D-GIXD results show that the intermediate state was dominant in edge -on lamellae configuration where the crystallographic b-axis is normal to the film surface. Meanwhile, the highly ordered state was predominant in flat -on lamellae configuration where the b-axis is parallel to the film surface. In the surface region, crystals strongly tended to align in an edge -on lamellae configuration.AMER CHEMICAL SOC, Jun. 2016, MACROMOLECULES, 49(11) (11), 4202 - 4210, English[Refereed]Scientific journal
- Recently, tip-enhanced Raman scattering (TERS) has made tremendous progress and is often used as a powerful technique for nanoscience and technology. TERS is an emerging spectroscopic tool that combines scanning probe microscopy and Raman spectroscopy. Compared with normal Raman spectroscopy, TERS has much higher spatial resolution and sensitivity, and thus is very suitable for the structure and interactions of polymer nanocomposites. This review reports Raman and TERS studies of polymer nanocomposites containing carbon nanotubes or graphenes. The principle and advantages of TERS are described briefly first in comparison with those of normal Raman spectroscopy. Then, the usefulness of Raman and TERS spectroscopy in studying structure and interactions of polymer nanocomposites is demonstrated by introducing four examples.Elsevier Inc., Feb. 2016, Spectroscopy of Polymer Nanocomposites, 88 - 111, English[Refereed]In book
- Polyglycolic acid (PGA), a biodegradable polyester with a simple molecular structure, shows an abnormally high melting point of 220 degrees C which is the highest among biopolyesters. In order to investigate this peculiar physical property and the structure of PGA, its temperature-dependent infrared (IR) spectra and wide angle X-ray diffraction (WAXD) were measured. Of note in the IR spectra is that among the many bands, those due to antisymmetric and symmetric CH2 stretching modes and that due to the C-O-C stretching mode show a significantly lower wavenumber shift with temperature increase. These experimental results suggest the existence of weak C-H center dot center dot center dot O (ether) hydrogen bonding along the (110) direction in PGA. WAXD results support this suggestion by an observed noticeable decrease of a unit cell length along the (110) direction. The natural bond orbital (NBO) calculations indicate there is weak intermolecular bonding between the C-H bond of the CH2 group and the oxygen atom of the -C-O-C- linkage. The quantum chemical calculations of the IR spectra were carried out for models of PGA based on the crystalline structure by using a partial optimization in the normal mode. The results can qualitatively explain the observed temperature dependence of the CH2 stretching modes of PGA, which is due to weakening of the C-H center dot center dot center dot O interactions among polymer chains with a temperature increase. All the experimental and theoretical calculation results suggest that there is weak hydrogen bonding between the CH2 group and the ether oxygen atom. This intermolecular interaction may be the cause for the abnormally high melting point of PGA.ROYAL SOC CHEMISTRY, 2016, RSC ADVANCES, 6(20) (20), 16817 - 16823, English[Refereed]Scientific journal
- Solvent evaporation crystallization (SEC) of poly(3-hydroxybutyrate) (PHB) in a PHB/chloroform solution was investigated by time-resolved attenuated total reflection Fourier-transform infrared (ATR-FTIR) spectroscopy and grazing incidence wide angle X-ray diffraction (GI-WAXD). The ATR-FTIR investigation reveals that the PHB/chloroform solution was in a homogeneous state at first, and with the evaporation of chloroform, the separated PHB from the chloroform solvent was in the mixture of intermediate and amorphous states, but no crystal structure formed due to the presence of chloroform. Subsequently, further evaporation induced a transition from intermediate to crystal structure and the formation of C=O center dot center dot center dot H-C intramolecular interactions within the latter. As the crystal structure developed, the intramolecular interaction changed from weak to strong due to the reduced intra-molecular distance within the lamella structure. The results of the GI-WAXD investigation suggest the presence of two kinds of intermediate structures with different order (less ordered and highly ordered). During SEC, the intermediate structures formed first, subsequently transforming into a crystal structure.ROYAL SOC CHEMISTRY, 2016, RSC ADVANCES, 6(97) (97), 95021 - 95031, English[Refereed]Scientific journal
- Crystallization behavior and intermolecular hydrogen-bonding interactions of poly(3-hydroxybutyrate) (PHB)/chitin blends on as-solution cast films were studied as a function of composition and temperature by differential scanning calorimetry (DSC), wide-angle X-ray diffraction (WAXD) and infrared (IR) spectroscopy. The significant changes were observed in the DSC curves, WAXD patterns and IR spectra of the blends with PHB <= 50 wt%. We found that the crystallinity of PHB decreases in the blends, however, its crystal structure is not much affected by blending with chitin. The appearance of a new band at around 1710-1714 cm(-1) clearly reveals the formation of intermolecular hydrogen bondings between the C=O groups of PHB and the O-H and N-H groups of chitin (C=O center dot center dot center dot H-O and C=O center dot center dot center dot H-N). It is very likely that these intermolecular C=O center dot center dot center dot H-N and C=O center dot center dot center dot H-O hydrogen bondings occur in the amorphous phase because of the reduction in the chain mobility in the blends with increasing chitin content, even above the melting temperature of PHB. The C=O center dot center dot center dot H-N and C=O center dot center dot center dot H-O hydrogen bondings are formed upon the cleavage of weak C=O center dot center dot center dot H3C hydrogen bondings of PHB. Thus, the formation of the C=O center dot center dot center dot H-N and C=O center dot center dot center dot H-O hydrogen bondings is accompanied by the decrease in the crystallinity of PHB in the blends. (C) 2015 Elsevier Ltd. All rights reserved.ELSEVIER SCI LTD, Sep. 2015, POLYMER, 75(75) (75), 141 - 150, English[Refereed]Scientific journal
- Wiley Blackwell, Feb. 2015, Characterization of Polymer Blends: Miscibility, Morphology and Interfaces, 705 - 730, English[Refereed]In book
- We aimed to achieve wide area rapid monitoring of the crystallinity change in poly(lactic acid) (PLA) during photodegradation caused by ultraviolet (UV) light by using a newly developed near-infrared (NIR) camera (Compovison). Several kinds of PLA samples with different crystallinities and their blends with poly, which then grow into layers of the intermediate structures [defined as mesomorphic layers (ML)] with the long spacings. These results were elucidated by analysis (5) and (6). In region II, LC start to be created from ML, which was elucidated by analysis (1) to (4), and both of the weight fractions of ML (X-inter) and LC (X-crys) increase with time [analysis (3)]. In region III, X-inter, and X-crys, decreases and increases with time, respectively [analysis (3)], because the transformation form ML to LC dominates the transformation from the density fluctuations to ML. The WAXD profiles due to ML in region I was identified by analysis (1), while those in regions H and III were identified by analysis (3).AMER CHEMICAL SOC, Jan. 2012, MACROMOLECULES, 45(1) (1), 313 - 328, English[Refereed]Scientific journal
- The laser heating effect on MWCNTs in styrene-butadiene rubber/multiwalled carbon nanotube (SBR/MWCNT) composites were studied by Raman spectra. The intensity ratio of the D band to G band (I-D/I-G) of SBR/MWCNT composites largely decreased with temperature. This indicates the self-rearranging behavior of MWCNTs in the SBR/MWCNTs system during temperature increase. In addition, the temperature-dependent downward shift of the G band of SBR/MWCNT composites was smaller than that of MWCNTs samples. The self-rearrangement of MWCNTs in SBR/MWCNT composites and a mechanical compression were explained as two possible reasons for the different behavior of the G band shift. (C) 2011 Elsevier B.V. All rights reserved.ELSEVIER SCIENCE BV, Jan. 2012, CHEMICAL PHYSICS LETTERS, 523, 87 - 91, English[Refereed]Scientific journal
- The exact molecular chain orientation of poly(beta-hydroxybutyrate) (PHB) in ultrathin films was successfully probed using surface-sensitive, grazing incidence X-ray diffraction techniques. The crystal orientation of spin-coated PHB films was very sensitive to free surface and thermal annealing. In pristine films, the free surface easily exerted its influence on PHB crystallization and caused lamellar orientation with the b-axis perpendicular to the film surface. The effect of the buried interface increased with temperature. With the increase in thermal annealing temperature, the lamellar orientation changed from the b-axis being perpendicular to the film surface to the c-axis becoming perpendicular to the film surface. As film thickness increased, the temperature, at which the lamellae with the b-axes oriented normal to the film surface disappeared, increased. The thickness and temperature dependence of the crystallization behavior of PHB in an ultrathin film could be attributed to the competition between the effects of the free surface and the buried interface. (C) 2011 Elsevier Ltd. All rights reserved.ELSEVIER SCI LTD, Aug. 2011, POLYMER, 52(17) (17), 3865 - 3870, English[Refereed]Scientific journal
- Effects of hydrogen bondings (HBs) on the isothermal crystallization kinetics and mechanisms of poly(3-hydroxybutyrate) (PHB) in neat PHB and its blends with cellulose acetate butyrate (CAB), amorphous melts at the crystallization temperature, were investigated by using time-resolved Fourier transform infrared spectroscopy (FTIR). The FTIR investigation focused on the characteristic bands of PHB in the crystalline phase and in the amorphous phase. The results revealed the following pieces of evidence. (1) The crystallization of PHB in both neat PHB and PHB/CAB blends commonly involves a multistep process: (i) transformation from amorphous melts to an intermediated structure between amorphous and crystals (process (b1) shown above), (ii) from the intermediate structure to crystals without intramolecular HBs (intra) (b2), and (iii) finally to crystals with intra (b3). (2) These transformations sequentially occur with increasing time. More specifically, the transformations (ii) and (iii) dominantly occur respectively in the primary and secondary crystallization process in both neat PHB and the blends. The Avrami analysis revealed that (3) the crystallization in both neat PHB and the blends involves essentially the same nucleation and growth mechanism, as evidenced by almost the same value of the Avrami exponent n; however (4) the crystallization rate constant k(A), also determined from the Avrami analysis, is strikingly reduced by blending CAB (see the k(A) value for the PHB/HCAB blend in the text), which is attributed to physical cross-links formed by intermolecular HBs between PHB and CAB in addition to molecular entanglements.AMER CHEMICAL SOC, May 2011, MACROMOLECULES, 44(9) (9), 3467 - 3477, English[Refereed]Scientific journal
- Thermal behavior and lamella structures of poly(3-hydroxybutyrate-co-3-hydroxyvalerate), hereafter P(HB-co-HV) (Fly = 9, 15, 21, 28.8, 58.4, 73.9, and 88.6 mol %), were investigated using infrared (IR) spectroscopy, wide-angle X-ray diffraction (WAX])), and differential scanning calorimetry (DSC). Temperature-dependent IR and WAX]) measurements revealed that P(HB-co-HV) with low HV content (HV = 9, 15, and 21 mol %) has a PHB-type crystal structure with CH(3)center dot center dot center dot O=C hydrogen bonds, whereas P((HB-co-HV) with high HV content (HV = 73.9 and 88.6 mol %) has a PHV-type crystal structure with CH(2)center dot center dot center dot O=C hydrogen bonds. The results of IR measurements showed that the strength of the CH(3)center dot center dot center dot O=C hydrogen bonds in the P(HB-co-HV) (HV = 9, 15, and 21 mol %) copolymers is almost the same as that in PHB, whereas in the P(HB-co-HV) (HV = 28.8 mol %) copolymer, the hydrogen bonds become weaker. In the case of P(HB-co-HV) with higher HV content (MV = 73.9 and 88.6 mol %), the effect of lamella packing on CH(2)center dot center dot center dot O=C hydrogen bonding in the PHV crystal is not considerable because the side chain of the HB unit is shorter than that of the HV unit. Additionally, it seems that in the crystal structure of P(HB-co-HV) (HV = 58.4 mol %) there ire only very weak intermolecular interactions between a C=O group and either a CH(2) group or a CH(3) group because the region of transition of the crystal structure of P (HB-co-HV) from the PHB type to the PHV type occurs at around 50 mol % HV content. Therefore, it is very much possible that with increasing temperature the crystal structure of P(HB-co-HV) (HV = 58.4 mol %) is more likely to collapse than other P(HB-co-HV) copolymers.AMER CHEMICAL SOC, Apr. 2011, MACROMOLECULES, 44(8) (8), 2829 - 2837, English[Refereed]Scientific journal
- Mar. 2011, Macromolecules, 44, 2229-2239, English[Refereed]Scientific journal
- Far-ultraviolet (FUV) spectra of n-alkanes (n = 5-14) and branched alkanes were measured in their liquid state by using a newly developed attenuated total reflection (ATR)-FUV spectrometer to investigate spectra structure relationship in the FUV region. The n-alkanes show a broad band near 8.3 eV and a weak shoulder near 7.7 eV. The 8.3 eV band shows a lower energy shift with a significant intensity increase with the increase in the length of alkyl chain. We have assigned the 8.3 eV band to the overlap of two bands due to the transition from the highest occupied molecular orbital (HOMO) to 3p and that from the HOMO-1 to 3s based on the observation that the peak energy of the 8.3 eV band of the n-alkanes is proportional to the first ionization energy. The 7.7 eV shoulder may be due to the transition from HOMO to 3s. The intensity of the 7.7 eV band increases markedly in the order n-alkanes without branch, with tertiary, and with quaternary carbon atoms. It is very likely that the forbidden transition from HOMO to 3s becomes allowed by the large decrease in symmetry upon going from the n-alkanes to the branched ones with the quaternary carbon, respectively.SAGE PUBLICATIONS INC, Feb. 2011, APPLIED SPECTROSCOPY, 65(2) (2), 221 - 226, English[Refereed]Scientific journal
- John Wiley and Sons, Jan. 2011, Raman, Infrared, and Near-Infrared Chemical Imaging, 261 - 281, English[Refereed]In book
- Temperature-dependent terahertz (THz) absorption spectra of poly(3-hydroxyalkanoate)s (PHAs) were measured by using a Fourier transform far-infrared (FT-FIR) spectrometer and a THz time-domain spectrometer over a temperature range of 10 K to 465 K with a liquid helium cryostat and a heating cell. Clear differences were observed between the spectra of crystalline and amorphous polyhydroxybutyrate (PHB), indicating that the absorption peaks observed in the THz spectra originated in the higher-order conformation of PHB. The polarization spectra of a stretched PHB sample were measured, and the direction of the vibrational transition moment was determined. The temperature dependences of the spectra reveal frequency shifts and broadening of the absorption peaks with temperature, suggesting large anharmonicity of the vibrational potential. The temperature shift behaviour is quite different in each transition. Some of the transitions show a blue shift, which cannot be explained by a simple anharmonic potential model. Frequency shifts of the peaks were mainly observed below 10 THz, which suggests a large anharmonicity of the vibrational potential at lower frequencies.ROYAL SOC CHEMISTRY, 2011, PHYSICAL CHEMISTRY CHEMICAL PHYSICS, 13(20) (20), 9173 - 9179, English[Refereed]Scientific journal
- Terahertz Spectroscopy of Poly(3-hydroxyalkanoate)sTerahertz (THz) absorption spectra of poly(3-hydroxyalkanotes) (PHA) were measured by a terahertz timedomain spectrometer and Fourier transform far-infrared spectrometer. Clear differences were observed between the spectra of crystalline and amorphous PHA, indicating that the absorption peaks observed in the THz spectra originated in the higher-order conformation of PHA. Direction of the vibrational transition moments was obtained by the polarization spectra of stretched sample in which the crystal axis were aligned. THz spectra were also measured over a temperature range from 10 K to 465 K with a liquid helium cryostat and a heating cell. The temperature dependences of the spectra reveal frequency shifts and broadening of the absorption peaks with temperature, suggesting large anharmonicity of the vibrational potential.IEEE, 2011, 2011 ANNUAL REPORT CONFERENCE ON ELECTRICAL INSULATION AND DIELECTRIC PHENOMENA, VOLS 1 AND 2, 195 - 198, English[Refereed]International conference proceedings
- Relationships between composition- and temperature-dependent intermolecular interactions and cold crystallization behaviors of poly(3-hydroxybutyrate) (PHB)/ cellulose acetate butyrate (CAB) blends have been investigated mainly by infrared (IR) spectroscopy, together with differential scanning calorimetry, and wide-angle X-ray diffraction (WAXD). Weak intermolecular hydrogen bondings between OH groups in CAB and C=O groups in amorphous part of PHB define as inter were detected in OH stretching bands of the blends. These interactions occur in the blends with high CAB content (w(CAB)) and highly depend on temperature. For all the blends having 0.2 <= w(CAB) <= 0.7, when temperature is raised (e.g., above 90 degrees C for the blend with w(CAB) = 0.5) the cold crystallization of PHB was discerned, as evidenced by an increase of the absorbance of the band due to C=O stretching in the crystal field. The crystallization was found to involve the dissociation of inter and transformation of inter into intramolecular hydrogen bondings within PHB and within CAB as summarized in Table 2 in this text, which promotes the crystallization and enhances stabilization of the crystals. Consequently, the crystallization of the PHB is influenced by exchanges of the hydrogen bondings as described above with raising temperatures. X-ray diffraction from PHB crystals in the blends show a remarkable decrease of crystallinity with w(CAB) and eventually disappear when w(CAB) >= 0.8. (C) 2010 Elsevier Ltd. All rights reserved.ELSEVIER SCI LTD, Jan. 2011, POLYMER, 52(2) (2), 461 - 471, English[Refereed]Scientific journal
- Variable-temperature FT-IR spectra of poly(3-hydroxybutyrate) (PHB), poly(epsilon-caprolactone) (PCL) and a PHB/PCL (50:50 wt.%) blend were analyzed by two-dimensional correlation spectroscopy (2DCOS). For this purpose the nu(C=O) region was employed to characterize in some detail the crystallization behavior of the investigated polymer systems during cooling from the melt. The asynchronous 2D correlation spectra clearly captured the existence of three components in the crystallinity-sensitive region of the C=O stretching mode for PHB and PCL, respectively: a well-ordered, an inter-mediate and a less ordered crystalline state. Furthermore, by 2DCOS application a sequential order of the observed structural changes could be proposed for the whole temperature range during the crystallization of both polymers. In the case of the PHB/PCL (50:50 wt.%) polymer blend, we have split up the spectral data set in the sub-sets between 200-120 degrees C and 70-30 degrees C for a more detailed 2DCOS analysis. In this way we could separate the crystallization process of PHB and PCL in the polymer blend.WILEY-V C H VERLAG GMBH, 2011, POLYMER SPECTROSCOPY, 305, English[Refereed]International conference proceedings
- Isothermal crystallization of poly(3-hydroxybutylate) was observed by the temporal change of terahertz absorption spectra. The obtained spectra were analyzed by using two-dimensional correlation spectroscopy. Synchronous and asynchronous plots show the correlation of the absorption peaks and the order of the spectral change, which helps to understand the crystallization process.IEEE, 2011, 2011 36TH INTERNATIONAL CONFERENCE ON INFRARED, MILLIMETER, AND TERAHERTZ WAVES (IRMMW-THZ), 100, 011907-1-3, English[Refereed]International conference proceedings
- Terahertz absorption spectra of poly (3-hydroxyalkanoates) with different conformations were measured by using a terahertz time domain spectrometer. Sharp absorption peaks were observed in the spectrum of crystalline samples. The orientation direction of the transition dipole moment was investigated by the polarization spectra. The peak at 2.92 THz was assigned to a vibration of helical structure along the fiber axis, and the peak at 2.49 THz was attributed to a vibration due to the hydrogen bonding between helix structures. The temperature dependence of the spectra reflects the change in the hydrogen bonding distance and melting process of the crystalline structure. (C) 2010 American Institute of Physics. [doi:10.1063/1.3358146]AMER INST PHYSICS, Mar. 2010, APPLIED PHYSICS LETTERS, 96(10) (10), English[Refereed]Scientific journal
- Mar. 2010, Applied Clay Science, 48, 73–80, English[Refereed]Scientific journal
- Mar. 2010, Macromolecules, 43, 3897–3902, English[Refereed]Scientific journal
- Terahertz absorption spectra of Poly(3-hydroxybutyrate)s were measured. The orientation of the transition dipole moment was investigated by the polarization spectra. The temperature dependence of the spectra reflects the change in the hydrogen bonding distance of the crystalline structure.IEEE, 2010, 35TH INTERNATIONAL CONFERENCE ON INFRARED, MILLIMETER, AND TERAHERTZ WAVES (IRMMW-THZ 2010), 96, 101904, English[Refereed]International conference proceedings
- Variable-Temperature Fourier Transform Infrared Spectroscopic Investigations of Poly(3-Hydroxyalkanoates) and Perturbation-Correlation Moving-Window Two-Dimensional Correlation Analysis. Part II: Study of Poly(epsilon-Caprolactone) Homopolymer and a Poly(3-Hydroxybutyrate)-Poly(epsilon-Caprolactone) BlendIn the present study, variable-temperature Fourier transform infrared (FT-IR) spectra of a poly(epsilon-caprolactone) (PCL) homopolymer and a poly(3-hydroxybutyrate) (PHB)-poly(epsilon-caprolactone) (PCL) blend were analyzed by generalized two-dimensional correlation spectroscopy (2DCOS) and perturbation-correlation moving-window two-dimensional (PCMW2D) correlation spectroscopy. The C=O stretching vibration bands of PCL and PHB were employed to explore the structural changes in the PCL homopolymer and the PHB-PCL blend during the heating process. For the melting of PCL homopolymer in the temperature range of 50 to 70 degrees C, we observed in the synchronous and asynchronous 2D correlation spectra one crystalline (1724 cm(-1)) and one amorphous (1737 cm(-1)) C=O stretching vibration band, which are also detectable in the one-dimensional FT-IR spectra. This result was also confirmed by PCMW2D correlation spectroscopy. During the heating process of the PHB-PCL blend in the temperature range 3(),-200 degrees C, the PCMW2D correlation analysis provided detailed information. Thus, in the synchronous PCMW2D correlation spectrum the melting of PCL was observed in the temperature region between 30 and 70 degrees C. The recrystallization of PHB in the blend in the temperature range 70-120 degrees C was accompanied by a shift of the C=O stretching band from higher wavenumber (1724 cm(-1)) corresponding to an imperfect crystalline state to the lower wavenumber (1721 cm(-1)) characteristic of a well-ordered crystalline state. In the temperature range 120-200 degrees C the melting process of PHB in the blend is captured by a sharp transition from the crystalline (1722 cm(-1)) to the amorphous (1747 cm(-1)) C=O stretching band.SOC APPLIED SPECTROSCOPY, Sep. 2009, APPLIED SPECTROSCOPY, 63(9) (9), 1034 - 1040, English[Refereed]Scientific journal
- Generalized two-dimensional correlation spectroscopy (2DCOS) and perturbation-correlation moving-window two-dimensional (PCMW2D) correlation spectroscopy were applied to explore the melting behavior of non-annealed and annealed poly(3-hydroxybutyrate) (PHB) homopolymer as studied by variable-temperature Fourier transform infrared (FT-IR) spectroscopy. The absorption band of the C=O stretching vibration was employed to investigate the structural changes during the heating process (30-200 degrees C). Non-annealed PHB showed a recrystallization process in the temperature range 30-120 degrees C. In the asynchronous 2D correlation spectrum we clearly captured the existence of two components in the crystallinity-sensitive wing of the C=O stretching mode: a well-ordered crystalline state at lower wavenumbers (1718 cm(-1)) and a less ordered crystalline state at higher wavenumbers (1724 cm(-1)). These crystallinity-sensitive bands at 1718 and 1724 cm(-1), which are not readily detectable in the one-dimensional (ID) FT-IR spectra, share asynchronous cross-peaks with bands at around 1737 and 1747 cm(-1) assignable to the C=O stretching absorptions due to the amorphous components. In the case of the melting process of non-annealed PHB in the temperature range 120-200 degrees C, it is helpful to use the PCMW2D correlation analysis, which indicates the recrystallization between 40 and 110 degrees C by the shift of the C=O stretching band from 1726 cm-1 to 1722 cm-1 and the sharp change to the broad amorphous C=O stretching absorption at 1747 cm(-1) at the melting temperature of PHB around 190 degrees C. For an annealed sample of PHB only the melting behavior was observed in the PCMW2D correlation analysis by the sharp transition from the crystalline to the amorphous C=O stretching band.SOC APPLIED SPECTROSCOPY, Sep. 2009, APPLIED SPECTROSCOPY, 63(9) (9), 1027 - 1033, English[Refereed]Scientific journal
- Infrared reflection-absorption (IR-RAS) and transmission spectra were measured for poly(3-hydroxybutyrate) (PHB) thin films to explore its specific crystal structure in the Surface region. As IR-RAS is sensitive to the vibration mode of perpendicular orientation of the surface, differences between IR-RAS and transmission spectra indicate an orientation of the lamella structure in the surface of PHB thin films. The relative intensity of the Crystalline C=O Stretching band in the IR-RAS spectrum is significantly weaker than that in the transmission spectrum. It may be concluded that the transient dipole moment of the C=O stretching mode of the crystalline state is not oriented perpendicular but nearly parallel to the substrate surface. On the other hand, the relative intensity of the band at 3009 cm(-1) due to the C-H stretching mode of the C-H... O=C hydrogen bonding is similar between the IR-RAS and transmission spectra, suggesting that the C-H bond is oriented neither perpendicular nor parallel to the substrate surface but in an intermediate direction. Since the C=O group of the C-H center dot center dot center dot O=C hydrogen bonding is oriented nearly parallel to the surface and its C-H group is in the intermediate direction, it is very likely that the C-H center dot center dot center dot O=C hydrogen bonding has a somewhat bent structure. These results are in good agreement with our previous conclusion that the C-H center dot center dot center dot O=C hydrogen bonding of PHB exists along the a-axis (not the b-axis) between the CH(3) group of one helix and the C=O group of another helix. (C) 2008 Elsevier B.V. All rights reserved.ELSEVIER SCIENCE BV, Sep. 2009, VIBRATIONAL SPECTROSCOPY, 51(1) (1), 132 - 135, English[Refereed]Scientific journal
- In the present study, variable-temperature Fourier transform infrared (FT-IR) spectra of a poly(ε-caprolactone) (PCL) homopolymer and a poly(3-hydroxybutyrate) (PHB)-poly(ε-caprolactone) (PCL) blend were analyzed by generalized two-dimensional correlation spectroscopy (2DCOS) and perturbation-correlation moving-window two-dimensional (PCMW2D) correlation spectroscopy. The C=O stretching vibration bands of PCL and PHB were employed to explore the structural changes in the PCL homopolymer and the PHB-PCL blend during the heating process. For the melting of PCL homopolymer in the temperature range of 50 to 70 °C, we observed in the synchronous and asynchronous 2D correlation spectra one crystalline (1724 cm-1) and one amorphous (1737 cm-1) C=O stretching vibration band, which are also detectable in the one-dimensional FT-IR spectra. This result was also confirmed by PCMW2D correlation spectroscopy. During the heating process of the PHB-PCL blend in the temperature range 30-200 °C, the PCMW2D correlation analysis provided detailed information. Thus, in the synchronous PCMW2D correlation spectrum the melting of PCL was observed in the temperature region between 30 and 70 °C. The recrystallization of PHB in the blend in the temperature range 70-120 °C was accompanied by a shift of the C=O stretching band from higher wavenumber (1724 cm-1) corresponding to an imperfect crystalline state to the lower wavenumber (1721 cm-1) characteristic of a well-ordered crystalline state. In the temperature range 120-200 °C the melting process of PHB in the blend is captured by a sharp transition from the crystalline (1722 cm-1) to the amorphous (1747 cm-1) C=O stretching band. © 2009 Society for Applied Spectroscopy.Sep. 2009, Applied Spectroscopy, 63(9) (9), 1034 - 1040, English[Refereed]Scientific journal
- In this study, we develop a new facile method to prepare nylon-6 with special features (denoted as vp-nylon-6). The key strategy for the method is to make the crystallization of nylon-6 be performed in a slow and near-equilibrium manner by diffusing the vapor of precipitator into a nylon 6/formic acid solution at ambient temperature and pressure. Differential scanning calorimeter (DSC) and wide angle X-ray diffraction (WAXD) have demonstrated that the crystallinity and crystalline perfection of vp-nylon-6 ire significantly improved by the new method. Scanning electron microscope (SEM) observations have shown that vp-nylon-6 exhibits versatile morphological feature including ribbon, bowknot, flower, semisphere, and dumbbell which are the result of the assembly of crystalline lamellae. The crystalline lamellae occur in a discrete fashion rather than being embedded in an amorphous matrix even if concentrated nylon Solutions are used. Selected area electron diffraction (SAED) in transmission electron microscope (TEM) shows that the crystalline lamellae are composed of single crystals.AMER CHEMICAL SOC, Feb. 2009, MACROMOLECULES, 42(4) (4), 1175 - 1179, English[Refereed]Scientific journal
- The miscibility, crystallization and subsequent melting behavior in binary biodegradable polymer blends of poly(L-lactic acid) (PLLA) and low molecular weight poly(3-hydroxybutyrate) (PHB) have been investigated by differential scanning calorimetry (DSC), Fourier-transform infrared (FTIR) spectroscopy, and wide-angle X-ray diffraction (WAXD). DSC analysis results indicted that PLLA showed no miscibility with high molecular weight PHB (M-w = 650,000 g mol(-1)) in the 80/20, 60/40, 40/60, 20/80 composition range of the PHB/PLLA blends. On the other hand, it showed some limited miscibility with low molecular weight PHB (M-w = 5000 g mol(-1)) when the PHB content was below 25%, as evidenced by small changes in the glass transition temperature of PLLA. The partial miscibility was further supported by changes of cold-crystallization behavior of PLLA in the blends. During the nonisothermal crystallization, it was found that the addition of a small amount of PHB up to 30% made the cold-crystallization of PLLA occur in the lower temperature. Meanwhile, the crystallization of PHB and PLLA was observed in the heating process by monitoring characteristic IR bands of each component for the low molecular weight PHB/PLLA 20/80 and 30/70 blends. The temperature-dependent IR and WAXD results also revealed that for PLLA component crystallization, the disorder (alpha') phase of PLLA was produced, and that the a' phase changed to the order (a) phase just prior to the melting point. (C) 2008 Elsevier Ltd. All rights reserved.ELSEVIER SCI LTD, Sep. 2008, POLYMER, 49(19) (19), 4204 - 4210, English[Refereed]Scientific journal
- We have investigated crystal structure and C-H⋯=C hydrogen bonding by using infrared (IR) spectroscopy and wide-angle X-ray diffraction (WAXD) for poly(3-hydroxyvalerate) (PHV) in comparison with those of poly(3- hydroxybutyrate) (PHB). We have explored the distances between the C=O group in one helix and the CH3 or CH2 groups in the other helix of PHV by using X-ray crystallographic data. It has turned out that the distance between the C=O group and the CH3 group of PHV is longer than that of the van der Waals separation (2.72 Å), while the distance between the C=O group and the two CH2 groups in the main and side chains of PHV is significantly shorter than that of the van der Waals separation. Therefore, it is very likely that PHV has C-H& mellipO=C hydrogen bondings between the C=O group and the one or two CH2 groups in the main or side chains. Of particular note is that CH2 antisymmetric and symmetric stretching bands of PHV show large blue shifts, which are characteristic of C-H⋯O hydrogen bondings. These strongly support the existence of CH 2⋯O=C hydrogen bondings in PHV. PHV shows three crystalline C=O stretching bands at 1740, 1725, and 1721 cm-1, suggesting that the C=O groups are in three different environments in the PHV crystal. The frequencies of the 1725 and 1721 cm-1 bands are very close to that of the crystalline C=O stretching band of PHB (1723 cm-1). We have assigned these two C=O stretching bands of PHV to the C=O group that has hydrogen bonds with both side chain and main chain CH2 groups and that has a hydrogen bond with one of the CH2 groups. Temperature-dependent increases in the a and b lattice parameters of PHV indicate mat the directions of C-H⋯O=C hydrogen bondings are almost in parallel to me (110) diffraction, which is the chain folding direction of PHV. PHB has a particular C-H⋯O=C hydrogen bonding between the C=O group and the CH3 group along the a axis ((110) to (11̄0) direction), which is the same direction as its chain folding direction. The difference in the chain folding direction between PHV and PHB may come from the difference in the inter- or intramolecular interactions in their crystal structures. © 2008 American Chemical Society.Jun. 2008, Macromolecules, 41(12) (12), 4305 - 4312, English[Refereed]Scientific journal
- The crystallization behavior of microbially synthesized poly(3-hydroxybutyrate) (PHB) and its copolymers [P(HB-co-HHx)] containing 2.5, 3.4, and 12 mol % 3-hydroxyhexanoate (HHx) comonomer and the melting of the resultant crystals were studied in detail using time-resolved small-angle X-ray scattering and differential scanning calorimetry. The polyesters were found to undergo primary crystallization as well as secondary crystallization. In-the primary crystallization, the thicknesses of the lamellar crystals were sensitive to the crystallization temperature, but no thickening was observed throughout the entire crystallization at a given temperature. The thickness of the lamellar crystals in the PHB homopolymer was always larger than that of the amorphous layers. In the copolymers, by contrast, the randomly distributed HHx comonomer units were found to be excluded from the lamellar crystals into the amorphous regions during the isothermal crystallization process. This interrupted the crystallization of the copolymer chains, resulting in the formation of lamellar crystals with thicknesses smaller than those of the amorphous layers. The lamellar crystals in the copolymers had lower electron densities compared to those formed in the PHB homopolymer. On the other hand, secondary crystallization favorably occurred during the later stage of isothermal crystallization in competition with the continuous primary crystallization, forming secondary crystals in amorphous regions, in particular in the amorphous layers between the primarily formed lamellar crystal stacks. Compared to the primarily formed lamellar crystals, the secondary crystals had short-range-ordered structures of smaller size, a broader size distribution, and a lower electron density.AMER CHEMICAL SOC, Apr. 2008, JOURNAL OF PHYSICAL CHEMISTRY B, 112(15) (15), 4571 - 4582, English[Refereed]Scientific journal
- We investigate surface morphology and crystalline structure of biodegradable polymers poly(3-hydroxybutyrate) (PHB) and its random copolymer poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (P(HB-co-HHx), HHx = 12 mot %) using surface-sensitive techniques. Surface region typically to a depth of about 10 nm of polymer films which have thickness ranging from 20 to 120 nm is observed by grazing incidence X-ray diffraction (GIXD), X-ray reflectivity (XR), and atomic force microscopy (AFM). Both PHB and P(HB-co-HHx) show that crystallographic b-axis of crystallites in the surface region is aligned in the direction normal to the surface. It indicates that intermolecular interaction along a-axis is still dominant in the surface region, which would also determine the fastest growth direction of crystalline lamellae. A lattice relaxation peculiar to P(HB-co-HHx) surfaces is recognized in the b-axis length. As temperature is raised, crystalline lamellae characterized by densely packed molecular chains appear, implying a thermally activated transformation from metastable lamellae to stable ones. The metastable lamellae in which molecular chains fold loosely are mainly observed throughout rapid cooling, although the loosely and densely packed lamellae equally form in slow cooling. Furthermore, continuous lamellae melting at the surface is observed, all of which suggest an additional process for forming the metastable long-range order in the surface region. Crystallinity at polymer surface would also be responsible for the difference in surface morphology between PHB and P(HB-co-HHx) revealed by XR and AFM.AMER CHEMICAL SOC, Mar. 2008, MACROMOLECULES, 41(5) (5), 1713 - 1719, English[Refereed]Scientific journal
- INT UNION CRYSTALLOGRAPHY, 2008, ACTA CRYSTALLOGRAPHICA A-FOUNDATION AND ADVANCES, 64, C547 - C547, English
- The thermal degradation behavior of poly(3-hydroxybutyrate) (PHB) and poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (P(HB-co-HHx), HHx = 12 mol%) has been studied under different environmental conditions by thermogravimetric analysis (TGA) Fourier transform infrared (FT-IR) spectroscopy. It is reported that at higher temperature (> 400 degrees C) carbon dioxide and propene are formed from the decomposition product crotonic acid in a nitrogen atmosphere, whereas in an oxygen atmosphere propene oxidizes in a further step to carbon dioxide, carbon monoxide and hydrogen. It was also found that PHB and P(HB-co-HHx) have a similar thermal degradation mechanism. The analysis of the FT-IR-spectroscopic data was performed with 2D and perturbation-correlation moving-window 2D (PCMW2D) correlation spectroscopy.SOC APPLIED SPECTROSCOPY, Jul. 2007, APPLIED SPECTROSCOPY, 61(7) (7), 755 - 764, English[Refereed]Scientific journal
- The aim of the present study is to propose a totally new technique for the utilization of far-ultraviolet (UV) spectroscopy in polymer thin film analysis. Far-UV spectra in the 120-300 nm region have been measured in situ for six kinds of commercial polymer wrap films by use of a novel type of far-UV spectrometer that does not need vacuum evaporation. These films can be straightforwardly classified into three groups, polyethylene (PE) films, polyvinyl chloride (PVC) films, and polyvinylidene chloride (PVDC) films, by using the raw spectra. The differences in the wavelength of the absorption band due to the sigma-sigma* transition of the C-C bond have been used for the classification of the six kinds of films. Using this method, it was easy to distinguish the three kinds of PE films and to separate the two kinds of PVDC films. Compared with other spectroscopic methods, the advantages of this technique include nondestructive analysis, easy spectral measurement, high sensitivity, and simple spectral analysis. The present study has demonstrated that far-UV spectroscopy is a very promising technique for polymer film analysis.SOC APPLIED SPECTROSCOPY, Jul. 2007, APPLIED SPECTROSCOPY, 61(7) (7), 780 - 783, English[Refereed]Scientific journal
- The multiple melting behavior of poly (3-hydroxybutyrate-co-3-hydroxyhexanoate) (P(HB-co-HHx)) (HHx = 12 mol%) isothermally crystallized from the melt state has been characterized by differential scanning calorimetry (DSC) and Fourier transform infrared (FTIR) spectroscopy. The influence of different experimental variables (such as crystallization temperature, time, and heating rate) on the multiple melting behavior of P(HB-co-HHx) was investigated by using DSC. Moreover, it has been further examined by monitoring intensity changes of the characteristic IR bands during the subsequent heating process. For the isothermally crystallized P(HB-co-HHx) samples, triple melting peaks were observed upon heating. The weak lowest-temperature DSC endotherm I always appears at the position just above the crystallization temperature, and shifts to a higher temperature linearly with the logarithm of the crystallization time. The combination of DSC and IR results suggested that the occurrence of peak I was a result of the melting of crystals formed upon long-time annealing. As for the other two main melting endothermic peaks, endotherm 11 corresponds to the melting of crystals formed during the primary crystallization, and endotherm III is ascribed to the melting peak of the crystals formed by recrystallization during the heating process. (c) 2007 Published by Elsevier Ltd.ELSEVIER SCI LTD, Jul. 2007, POLYMER, 48(16) (16), 4777 - 4785, English[Refereed]Scientific journal
- The homogeneity of blends of poly((R)-3-hydroxybutyrate) (PHB) and poly(L-lactic acid) (PLLA) was evaluated by the near infrared chemical imaging (NIRCI) technique. NIRCI can nondestructively investigate a sample over a wide field of view within a few minutes to acquire a large number of spatially resolved NIR spectral data. NIRCI may be combined with multivariate analysis not only for qualitative analysis but also for statistically based quantitative analysis. The score images derived from the partial least squares regression (PLSR) analysis directly show that PHB/PLLA blends are highly homogeneous. The standard deviations (STD) of the histograms, indicating the distribution of the score values, show small values for the blends. These results qualitatively and quantitatively show the high level of homogeneity of PHB/PLLA blends. The predictions of the spatially averaged concentrations of the blend components obtained from PLSR results show values similar to the actual contents for the blends. The small errors of the predictions are also explained by STD values.JAPAN SOC ANALYTICAL CHEMISTRY, Jul. 2007, ANALYTICAL SCIENCES, 23(7) (7), 871 - 876, English[Refereed]Scientific journal
- Principal component analysis-based two-dimensional (PCA2D) correlation spectroscopy, combined with the eigenvalue manipulating transformation (EMT) of a spectral data set, was applied to the temperature-dependent IR spectra of poly(hydroxybutylate) (PHB). In asynchronous PCA2D correlation spectrum, we clearly captured the existence of two components in the crystalline band of the C=O stretching mode, well-ordered primary crystals observed at lower wavenumber and less ordered secondary crystals observed at higher wavenumber, which is not readily detectable in the ID spectra. By lowering the power of a set of eigenvalues associated with the original data, subtle differences in the thermal responses of PHB, which are difficult to observe even by conventional 2D correlation analysis, are revealed. When the contributions from minor factors are enhanced by eigenvalue manipulating transformation, intensities of bands assignable to the amorphous component of PHB are accentuated more in the C-O-C stretching region, while the intensities of bands assignable to the crystalline component become most prominent in the CH stretching region. However, the 2D correlation between CH and C=O stretching region reveals that the spectral intensity change of the CH3 stretching bands at 2975 cm(-1) contains a component due to the amorphous contribution.JAPAN SOC ANALYTICAL CHEMISTRY, Jul. 2007, ANALYTICAL SCIENCES, 23(7) (7), 881 - 889, English[Refereed]Scientific journal
- The crystallization behavior of microbially synthesized poly(3-hydroxybutyrate) was studied in detail using time-resolved small-angle X-ray scattering. This polyester was found to undergo primary crystallization as well as secondary crystallization. In the primary crystallization, the thicknesses of the lamellar crystals were sensitive to the crystallization temperature, but no thickening was observed throughout the entire crystallization at a given temperature. The thickness of the lamellar crystals in the polyester was always larger than that of the amorphous layers. Secondary crystallization favorably occurred during the later stage of isothermal crystallization in competition with the continuous primary crystallization, forming secondary crystals in amorphous regions, in particular in the amorphous layers between the primarily formed lamellar crystal stacks. Compared to the primarily formed lamellar crystals, the secondary crystals had short-range-ordered structures of smaller size, a broader size distribution, and a lower electron density.BLACKWELL PUBLISHING, Apr. 2007, JOURNAL OF APPLIED CRYSTALLOGRAPHY, 40, S594 - S598, English[Refereed]Scientific journal
- Infrared (IR) and Raman spectra were measured for four kinds of ultra-high-molecular-weight poly [(R)-3-hydroxybutyrate] (UHMW-PHB) films: a solvent-cast film, a cold-drawn film, a two-step-drawn film, and a hot-drawn film. Quantum chemical calculations were made for octamer models of UHMW-PHB with a helix conformation (alpha-form) and a planar zigzag conformation (beta-form). Comparison of the results between the Raman spectra of four kinds of films and the quantum chemical calculations of octamer models revealed that only two-step-drawn film yields additional bands at 1735, 966, 935, 908, and 858 cm(-1) assignable to the beta-structure, suggesting that it contains the beta-form as well as the alpha-form. Detailed comparison of the frequencies and intensities of Raman bands between the observed and calculated values for the beta-form indicates that the amount of beta-form is relatively small and that the beta-structure has a less ordered structure. The infrared and Raman spectra of two-step-drawn film also indicate that it has more amorphous parts than other films. When the two-step-drawn film was further heated up to 130 degrees C and then cooled down to room temperature, the above additional bands due to the beta-form disappeared in the Raman spectra, suggesting that the beta-form is less stable than alpha-form. (c) 2007 Elsevier Ltd. All rights reserved.ELSEVIER SCI LTD, Apr. 2007, POLYMER, 48(9) (9), 2672 - 2680, English[Refereed]Scientific journal
- Morphology, chemical distribution and domain size in poly(ethylene terephthalate)/high-density poly(ethylene) (PET/HDPE) polymer blends of various ratios prepared with and without maleic anhydride have been analyzed with confocal Raman mapping and SEM. The ratioimage method introduced here allows us to obtain enhanced chemical images with higher contrast and reliability. Compatibility numbers (N-c) are calculated to evaluate the compatibility of the blends. The incompatible polymer blends show heterogeneous distribution with phase separation behavior, while the semicompatible blends prepared with maleic anhydride show much smaller subphase distributions with less distinct interphases. After the blending modification by maleic anhydride of only 0.5%, the viscosity status and dispersibility between PET and HDPE could be substantially improved, and the interactions that exist between the two phases have also been proved by ATR-FT-IR results. High-spatial-resolution confocal Raman mapping coupled with the ratioimage method provides a very attractive way to characterize the compatibility and phase behavior of the polymer blend through different blending methodologies. Copyright (C) 2006 John Wiley & Sons, Ltd.JOHN WILEY & SONS LTD, Mar. 2007, JOURNAL OF RAMAN SPECTROSCOPY, 38(3) (3), 260 - 270, English[Refereed]Scientific journal
- Comparison of miscibility and structure of poly((R)-3-hydroxybutyrate-co-(R)-3-hydroxyhexanoate) (P(HB-co-HHx)) (M-w = 638,000 g mol(-1)) and poly(L-lactic acid) (PLLA) (M,, = 150,000 g mol(-1)) with those of poly((R)-3-hydroxybutyrate) (PHB) (M-w = 600,000 g mol(-1)), and PLLA having the blending ratios was investigated by wide angle X-ray diffraction (WAXD), differential scanning calorimetry (DSC), and infrared (IR) microspectroscopy techniques. WAXD reflection patterns show that the lattice parameters of a and b axes for PHB and P(HB-co-HHx) are unchanged in their blends with PLLA regardless of blending ratio. These WAXD results suggest that their crystalline structures are independent of the second component. The glass transition temperature (T-g) of blend components did not significantly change. The crystallization temperature (T-g) of PLLA reveal that both PHB/PLLA and P(HB-co-HHx)/PLLA blends form mixed semicrystalline systems. The T-g of PLLA in the PHB/PLLA blends and that in the P(HB-co-HHx)/PLLA blends shift to opposite directions indicating that both blends are immiscible but exhibit different levels of compatibilities. Micro IR spectra show that crystalline bands due to PHB appear even for the 20/80 blend but those due to PLLA are hardly observed for all the PHB/PLLA blends investigated. On the other hand, the crystalline bands of PLLA are observed in the micro IR spectra of some spots in the 20/80 P(HB-co-HHx)/PLLA blend. Micro IR spectra also show significant differences in the compatibility and crystalline structures between the P(HB-co-HHx)/PLLA and PHB/PLLA blends. (c) 2007 Elsevier Ltd. All rights reserved.ELSEVIER SCI LTD, Mar. 2007, POLYMER, 48(6) (6), 1749 - 1755, English[Refereed]Scientific journal
- By adjusting the molecular weight of the poly(L-lactic acid) (PLLA) component in poly(3-hydroxybutyrate) (PHB)/PLLA blends, we investigated the crystallization behaviors of the two components in their immiscible and miscible 50:50 blends by real time infrared (IR) spectroscopy. In the immiscible PHB/PLLA blend, the stepwise crystallization of PHB and PLLA was realized at different crystallization temperatures. PLLA crystallizes first at a higher temperature (120 degrees C). Its crystallization mechanism from the immiscible PHB/PLLA melt is not affected by the presence of the PHB component, while its crystallization rate is substantially depressed. Subsequently, in the presence of crystallized PLLA, the isothermal melt-crystallization of PHB takes place at a lower temperature (90 degrees C). It is interesting to find that there are two growth stages for PHB. At the early stage of the growth period, the Avrami exponent is 5.0, which is unusually high, while in the late stage, it is 2.5, which is very close to the reported value (n approximate to 2.5) for the neat PHB system. In contrast to the stepwise crystallization of PHB and PLLA in the immiscible blends, the almost simultaneous crystallization of PHB and PLLA in the miscible 50:50 blend was observed at the same crystallization temperature (110 degrees C). Detailed dynamic analysis by IR spectroscopy has disclosed that, even in such apparently simultaneous crystallization, the crystallization of PLLA actually occurs faster than that of PHB. It has been found that, both in the immiscible and miscible blends, the crystallization dynamics of PHB are heavily affected by the presence of crystallized PLLA.AMER CHEMICAL SOC, Dec. 2006, JOURNAL OF PHYSICAL CHEMISTRY B, 110(48) (48), 24463 - 24471, English[Refereed]Scientific journal
- A method based on noise perturbation in functional principal component analysis (NPFPCA) is for the first time introduced to overcome the noise interference problem in two-dimensional correlation spectroscopy (2D-COS). By the systematic addition of synthetic noise to the dynamic multivariate spectral data, the functional principal component analysis (FPCA) described in this report is able to accurately determine which eigenvectors are representing significant signals instead of noise in the original data. This feature is especially useful for the data reconstruction and noise filtering. Reconstructed data resulted from the smooth eigenvectors can produce much more reliable 2D correlation spectra by removing the correlation artifacts from noise, which in turn enable more accurate interpretation of the spectral variations. The usefulness of this method is demonstrated with a theoretical framework and applications to the 2D correlation analyses of both simulated data and temperature-dependent reflection-absorption infrared spectra of a poly(3-hydroxybutyrate) (PHB) thin film.AMER CHEMICAL SOC, Oct. 2006, JOURNAL OF PHYSICAL CHEMISTRY A, 110(39) (39), 11279 - 11290, English[Refereed]Scientific journal
- The molecular weight dependence of poly(L-lactide)/poly(D-lactide) (PLLA/PDLA) stereocomplex behavior at the air-water interface was studied by surface pressure-area (pi-A) isotherms and atomic force microscopy (AFM). It was found that the compression-induced sterecomplexation of a PDLA/PLLA equimolar blend with high molecular weight (M-w = 1 x 10(6) and 9.8 x 10(5), respectively) could occur at the air-water interface. This result is in marked contrast with the stereocomplexation of PDLA/PLLA blends in the bulk from the melt or in solutions, where the homocrystallites of either PLLA or PDLA rather than stereocomplex crystallites will be formed preferentially when the molecular weights of both polymers are higher than 1 x 10(5). Unexpectedly, the Langmuir-Blodgett behavior of the PDLA/PLLA blend with lower molecular weight (M-w = 4 x 10(3) and 3.2 x 10(3), respectively), which should be favored in the stereocomplex, was distinct from that of other higher molecular weight blends. AFM images clearly disclosed for the first time the morphological changes of the equimolar blends of PLLA and PDLA at the air-water interface induced by increasing the surface pressure of the monolayer. Of particular note, the bilayer mechanism for the plateau in the isotherm was directly verified by the AFM height images.AMER CHEMICAL SOC, Oct. 2006, BIOMACROMOLECULES, 7(10) (10), 2728 - 2735, English[Refereed]Scientific journal
- X-ray diffraction and infrared spectroscopy studies on crystal and lamellar structure and CHO hydrogen bonding of biodegradable poly(hydroxyalkanoate)Temperature-dependent, wide-angle, x-ray diffraction (WARD) patterns and infrared (IR) spectra were measured for biodegradable poly(3-hydroxybutyrate) (PHB) and its copolymers, poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) P(HB-co-HHx) (HHx=2.5, 3.4, 10.5, and 12 mol%), in order to explore their crystal and lamellar structure and their pattern of C-H(...)O=C hydrogen bonding. The WARD patterns showed that the P(HB-co-HHx) copolymers have the same orthorhombic system as PHB. It was found from the temperature-dependent WARD measurements of PHB and P(HB-co-HHx) that the a lattice parameter is more enlarged than the b lattice parameter during heating and that only the a lattice parameter shows reversibility during both heating and cooling processes. These observations suggest that an interaction occurs along the a axis in PHB and P(HB-co-HHx). This interaction seems to be due to an intermolecular C-H(...)O=C hydrogen bonding between the C=O group in one helical structure and the CH(3) group in the other helical structure. The x-ray crystallographic data of PHB showed that the distance between the O atom of the C=O group in one helical structure and the H atom of one of the three C-H bonds of the CH(3) group in the other helix structure is 2.63 angstrom, which is significantly shorter than the sum of the van der Waals separation (2.72 angstrom). This result and the appearance of the CH(3) asymmetric stretching band at 3009 cm(-1) suggest that there is a C-H(...)O=C hydrogen bond between the C=O group and the CH(3) group in PHB and P(HB-co-HHx). The temperature-dependent WARD and IR measurements revealed that the crystallinity of P(HB-co-HHx) (HHx=10.5 and 12 mol%) decreases gradually from a fairly low temperature, while that of PHB and P(HB-co-HHx) (HHx=2.5 and 3.5 mol%) remains almost unchanged until just below their melting temperatures. It was also shown from our studies that the weakening of the C-H(...)O=C interaction starts from just above room temperature and proceeds gradually increasing temperature. It seems that the C-H(...)O=C hydrogen bonding stabilizes the chain holding in the lamellar structure and affects the thermal behaviour of PHB and its copolymers.Lead, SPRINGER, Aug. 2006, MACROMOLECULAR RESEARCH, 14(4) (4), 408 - 415, English[Refereed]Scientific journal
- We have investigated the C-H center dot center dot center dot O=C hydrogen bonding and isothermal crystallization kinetics of poly(3-hydroxybutyrate) (PHB) at 125 degrees C by using near-infrared (NIR) spectroscopy, which allows us to investigate thick films. The NIR spectrum of a PHB film changes remarkably with the evolution of isothermal crystallization process. Accordingly, NIR bands due to the amorphous and crystalline states have been assigned. Particular attention has been paid to a NIR band at 5973 cm(-1) due to the first overtone of the C-H stretching mode and an IR band at 3435 cm(-1) due to the first overtone of the C=O stretching mode of the C-H center dot center dot center dot O=C hydrogen bonding combining two parallel helical structures of PHB. The anharmonicity of C-H (5973 cm(-1)) and C=O (3435 cm(-1)) bands arising from the crystalline parts and that of the amorphous C-H (5954 cm(-1)) and C=O (3457 cm(-1)) bands was investigated by using both IR and NIR data. The anharmonicity of crystalline C- H and C=O bands is significantly different from that of the amorphous C- H and C=O bands, supporting the idea that both CH and C=O bonds in the crystalline state are involved in the C-H center dot center dot center dot O=C hydrogen bonding. Principal component analysis (PCA) was used to analyze the real-time NIR difference spectra measured during the isothermal crystallization process. The result suggests that the crystallization process may be not a simple transition of binary mixture of the amorphous and ordered crystalline states. Moreover, the crystallization kinetics parameters of PHB have been obtained by combining PCA and Avrami equation based on the spectral regions instead of the intensity changes of certain bands.AMER CHEMICAL SOC, May 2006, MACROMOLECULES, 39(11) (11), 3841 - 3847, English[Refereed]Scientific journal
- The structure, dispersibility, and crystallinity of poly(3-hydroxybutyrate) (PHB) and poly(L-lactic acid) (PLLA) blends are investigated by using Raman microspectroscopy. Four kinds of PHB/PLLA blends with a PLLA content of 20, 40, 60, and 80 wt% were prepared from chloroform solutions. Differences in the Raman microspectroscopic spectra between the spherulitic and nonspherulitic parts in the blends mainly lie in the C=O stretching band and C-O-C and C-C skeletal stretching bands of PHB and PLLA. In addition to such bands, the Raman spectra of spherulitic structure in the blends show a band due to the CH(3) asymmetric stretching mode at an unusually high frequency (3009 cm(-1)), suggesting the existence of a C-H(...)O=C hydrogen bond of PHB in the spherulite. The existence of C-H(...)O=C hydrogen bond is one of the unambiguous evidence for the crystallization of PHB component in the blends. Therefore, it is possible to distinguish Raman bands due to each component in the spectra of blends. Raman spectra of the spherulitic structure in the blends are similar to a Raman spectrum of pure crystalline PHB, while those of the nonspherulitic parts in the blends have each component peak of PHB and PLLA. The present study reveals that the PHB component is crystallized in the blends irrespective of the blend ratio, and that both components are mixed in the nonspherulite parts. The crystalline structure of PHB and the nonspherulitic parts of PLLA in the blends are characterized, respectively, by the unique band of C-H... O=C hydrogen bond at 3009 cm(-1) and CCO deformation bands near 400 cm(-1). (c) 2006 Elsevier Ltd. All rights reserved.ELSEVIER SCI LTD, Apr. 2006, POLYMER, 47(9) (9), 3132 - 3140, English[Refereed]Scientific journal
- Temperature-dependent X-ray diffraction and infrared (IR) spectra were measured for poly(3-hydroxybutyrate) (PHB) and poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) P(HB-co-HHx) (HHx = 2.5, 3.4, 10.5, and 12 mol %) to explore their crystal and lamella Structure and the C-H center dot center dot center dot O=C hydrogen bonding in them. The X-ray diffraction and IR measurements of PHB and P(HB-co-HHx) revealed that the smaller the a lattice parameter, the higher the frequency (similar to 3008 cm(-1)) of the C-H stretching hand of the C-H center dot center dot center dot O=C hydrogen bonding along the a axis between the CH3 group of one helix and the C=O group of another helix. Therefore, it seems that the C-H center dot center dot center dot O=C hydrogen bonding becomes strong with the decrease in the a lattice parameter. To investigate the relation between the C-H center dot center dot center dot O=C hydrogen bonding and the lamella structure, we estimated file number of C-H center dot center dot center dot O=C hydrogen bonding along the c axis (the direction of the lamella thickness) based oil the reported lamella thickness. It is about 8 or 9 for PHB and about 3 for P(HB-co-HHx) (HHx = 10.5 and 12 mol %). It is very likely that the C-H center dot center dot center dot O=C hydrogen bondings break much more easily in P(HB-co-HHx) than in PHB because of the bulkiness of large amounts of amorphous parts. However, the polymer chains still keep the lamella Structure even in the copolymers with the HHx content of more than several percent. This is the reason why the P(HB-co-HHx) copolymers show high crystallinity and essentially have the same lattice spacing as the PHB homopolymer even if the HHx content is more than 10%. We have Concluded that the C-H center dot center dot center dot O=C hydrogen bonding stabilizes the chain folding in the lamella structure of PHB and P(HB-co-HHx) and the high crystallinity of PHB and P(HB-co-HHx) partly comes from the C-H center dot center dot center dot O=C hydrogen bonding.AMER CHEMICAL SOC, Feb. 2006, MACROMOLECULES, 39(4) (4), 1525 - 1531, English[Refereed]Scientific journal
- Studies on the molecular interaction of biodegradable polymers by using infrared spectroscopy and WAXDRecently, one of the biodegradable polymers, PLA gathers more attentions with increasing awareness to the environment. When the nanofillers are dispersed in the polymer matrix in a stable manner, it is called polymer nanocomposite. It is known that its physical properties are enhanced. Although many kinds of intercalated polymer-clay nanocomposites have been made, the mechanism is not known well. The purpose of this study is to compare the clay before and after the intercalation. In WAXD, the shift in the diffraction angle was observed, and this supports the formation of nanocomposites. In IR, the unique band due to intercalation was observed in the intercalated polymer spectra.2006, Polymer Preprints, Japan, 55(2) (2), 5586, JapaneseInternational conference proceedings
- CH...O=C hydrogen bonding in the crystalline structure of polyhydroxyvalerate studied by Infrared spectroscopy and quantum chemical calculationsBased on our previous IR studies, we have reported PHV has CH... O=C hydrogen bonding between the methylene group in is polymer chain and the carbonyl group. We have performing quantum chemical calculations upon PHV and determined the possibility of this hydrogen bonding.2006, Polymer Preprints, Japan, 55(2) (2), 5536, JapaneseInternational conference proceedings
- CH⋯O=C hydrogen bonding in the crystalline structures of polyhydroxyalcanoatesWe had reported PHB and P(HB-co-HV) have CH⋯O=C hydrogen bonding in their crystalline structures. But P(HB-co-HV) was thought to have that hydrogen bonding only with its HB part, so we examined PHV homopolymer by means of infrared spectroscopy. CH3 group of PHV does not have hydrogen bonding but CH2 may have it because C=O stretching band shows relatively low wavenumberand almost the same as PHB which indicate CH⋯O=C hydrogen bonding.2006, Polymer Preprints, Japan, 55(1) (1), 2272, JapaneseInternational conference proceedings
- Thermal behavior of PPL studied by infrared spectroscopy and WAXDIt has been reported that one of the biodegradable polymers, poly(β-propiolactone) (PPL), which has a similar chemical structure to PHB, can be chemically synthesized and has three different crystal structures (α, β, γ). Infrared spectra of β and γ structures were compared, and the unique bands at 1726 cm-1 originated from γ structure and 1750 cm-1 from β structure were observed in C=0 stretching region. From the temperature-dependent X-ray diffraction spectra, it was found that only the lattice constant a was gradually increasing with temperature due to the expansion of the crystal.2006, Polymer Preprints, Japan, 55(1) (1), 776, JapaneseInternational conference proceedings
- Infrared spectroscopy and x-ray diffraction studies on the thermal behavior and compatibility of poly(hydroxybutyrate)/poly(ethylene glycol) blendsThe miscibility, crystalline and lamella structures, and thermal behavior of poly(3-hydroxybutyrate) / poly(ethylene glycol) (Mw=35000) blends were investigated by means of wide-angle X-ray diffraction (WAXD), infrared (IR) spectroscopy, differential scanning calorimetry (DSC), scanning electron microscopy (SEM), and polarization microscope (POM).2006, Polymer Preprints, Japan, 55(1) (1), 898, JapaneseInternational conference proceedings
- The present study is aimed at investigating the molecular structure, crystallinity, and morphology of polyethylene (PE) and polypropylene (PP) blends by using Raman mapping, scanning electron microscopy (SEM), wide-angle X-ray diffraction (WAXD), and differential scanning calorimetry (DSC). In this study, three kinds of PEs, high-density polyethylene (HDPE), linear low-density polyethylene (LLDPE), and metallocene polyethylene (MEPE) were used. MEPE is one of the LLDPEs but its density is very low and its melt flow index (MFI) is very high. Blends of each PE and PP with a PP content ranging from 20 to 80 wt % with an increment of 20 wt % were prepared. Raman mapping images and SEM images show that the 80/20 blends of HDPE/PP and LLDPE/PP have similar dispersibility behavior and that only the 80/20 blend of MEPE/PP shows a different behavior in this respect. For the 20/80 blends, the differences are not so large. For the Raman mapping, the intensity ratio of the two bands at 1128 and 974 cm(-1) was used. The former is due to a symmetric C-C stretching mode of all-trans -(CH2)(n)- groups of PE while the latter is assigned to a CH3 rocking mode of PP. MEPE/PP blends yield quite different X-ray diffraction patterns compared to HDPE/PP and LLDPE/PP blends; the MEPE/PP blends show that with increasing MEPE content the crystalline size of PP become smaller. DSC curves of MEPE/PP show that the peak area changes linearly with the blending ratio and that the crystallization temperature does not change for any blend. These results mean that the density and MFI of PE influences the blend properties.SOC POLYMER SCIENCE JAPAN, 2006, POLYMER JOURNAL, 38(11) (11), 1127 - 1136, English[Refereed]Scientific journal
- Miscibility and hydrogen-bonding interactions, as well as the morphological properties, of biodegradable polymer blends of poly(3-hydroxybutyrate) (PHB) and a 80% hydrolyzed poly(vinyl alcohol) (PVA80) were studied using Fourier transform infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC). It was found that PHB is miscible with PVA80 in the amorphous phase over the whole composition range. PVA80 or PHB assumes the amorphous state when its content in the blend is lower than 30 or 20 wt %, respectively. Due to the heavy overlapping of C=O stretching bands from both PVA80 and PHB and the nonmeasurable peak shift in the OH stretching band region, hydrogen-bonding interactions between the OH group of PVA80 and the C=O group of PHB were not detectable at room temperature, but were observed at a higher temperature of 180 degrees C. This is because hydrogen-bonding interactions are promoted above the melting points of these two crystalline polymers, by increasing the mixing entropy and reducing the Delta chi effect. Blending PHB with PVA80 does not have a significant effect on the OH groups of PVA80 that are hydrogen bonded with each other. Instead, the C=O groups of PHB dispossess some of the OH groups that are hydrogen bonded to the C=O groups of PVA80, which gives rise to the miscibility between PVA80 and PHB in the amorphous phase.AMER CHEMICAL SOC, Oct. 2005, JOURNAL OF PHYSICAL CHEMISTRY B, 109(41) (41), 19175 - 19183, English[Refereed]Scientific journal
- Recently, we reported the isothermal crystallization behaviors of poly(L-lactic acid) (PLLA) from the melt and glassy states, respectively [J. Phys. Chem. B 2004, 108, 11514; Macromolecules 2004, 37, 6433]. Surprisingly, the quite different infrared (IR) spectral evolutions occur in the two crystallization processes at different temperatures in which the same crystal modification is expected to be formed. To clarify this unusual phenomenon, the crystal modifications and thermal behavior of PLLA samples prepared under different crystallization temperatures are investigated in detail by TEM, WAXD, and FTIR techniques. On the basis of the WAXD and IR data, a new crystal modification named the alpha form is proposed for the crystal structure of PLLA samples annealed at temperature below 120 degrees C. Such crystal modification with loose 10(3) helical chain packing is less thermally stable than the standard a form of PLLA. This assignment can explain all the experiment observations well. Other possible mechanisms for the IR spectral difference of bulk PLLA samples annealed at different temperatures are also discussed.AMER CHEMICAL SOC, Sep. 2005, MACROMOLECULES, 38(19) (19), 8012 - 8021, English[Refereed]Scientific journal
- The present study is aimed at investigating structure, dispersibility, and crystallinity of poly(3-hydroxybutyrate) (PHB) and poly(L-lactic acid) (PLLA) blends by using FT-IR microspectroscopy and differential scanning calorimetry (DSC). Four kinds of PHB/PLLA blends with a PLLA content of 20, 40, 60, and 80 wt % were prepared from chloroform solutions. Micro-IR spectra obtained at different positions of a PHB film are all very similar to each other, suggesting that there is no discernible segregated amorphous and crystalline parts on the PHB film at the resolution scale of micro-IR spectroscopy. On the other hand, the micro-IR spectra of two different positions of a PLLA film, where spherulite structures are observed and they are not observed, are significantly different from each other. PHB and PLLA have characteristic IR marker bands for their crystalline and amorphous components. Therefore, it is possible to explore the structure of each component in the PHB/PLLA blends by using micro-IR spectroscopy. The IR spectra of a position of blends except for the 20/80 blend are similar to that of pure PHB. On the other hand, the IR spectra of another position of the blend consist of the overlap of those of pure PHB and PLLA. For the 20/80 blend, it is difficult to find a position whose spectrum is similar to that of pure PHB. However, a crystalline peak due to the C=O stretching band is observed at 1718 cm(-1). This means that PHB crystallizes as very small spherulites or immature spherulites under such blend ratio. DSC curves of the blend show that the heat of crystallization of PHB varies with the blending ratio of PHB and PLLA. The recrystallization peak is detected for PLLA and the 20/80 blend respectively at 106.5 and 88.2 degrees C. The lowering of recrystallization temperature for the 20/80 blend compared with that of pure PLLA suggests that PHB forms small finely dispersed crystals that may act as nucleation sites of PLLA. The results for the PHB/PLLA blends obtained from IR microspectroscopy indicate that PHB crystallizes in any blends. However, crystalline structures of PHB in the 80/20, 60/40, and 40/60 blends are different from those of the 20/80 blend.AMER CHEMICAL SOC, Jul. 2005, MACROMOLECULES, 38(15) (15), 6445 - 6454, English[Refereed]Scientific journal
- This review paper reports infrared (IR) and Raman spectroscopy and quantum chemistry calculation studies of C-H center dot center dot center dot O hydrogen bondings and thermal behavior of biodegradable polyhydroxyalkanoates. IR and Raman spectra were measured for poly(3-hydroxybutyrate) (PHB) and a new type of bacterial copolyester, poly(3-hydroxybutyrate-co-3-hydroxyhexanoate), P(HB-co-HHx) (HHx = 12 mol%) over a temperature range of 20 T to higher temperatures (PHB, 200 degrees C; HHx = 12 mol%, 140 degrees C) to explore their structure and thermal behavior. One of bands due to the CH3 asymmetric stretching modes appears near 3010 cm(-1) in the IR and Raman spectra of PHB and P(HB-co-HHx) at 20 T. These frequencies of IR and Raman CH3 asymmetric stretching bands are much higher than usual. These anomalous frequencies of the CH3 asymmetric stretching bands together with the X-ray crystallographic structure of PHB have suggested that there is an inter- or intramolecular C-H... 0 hydrogen bond between the C=O group in one helical structure and the CH3 group in the other helical structure in PHB and P(HB-co-HHx). The quantum chemical calculation of model compounds of PHB also has suggested the existence of C-H... 0 hydrogen bonds in PHB and P(HB-co-HHx). It is very likely that a chain of C-H... 0 hydrogen bond pairs link two parallel helical structures in the crystalline parts. The temperature-dependent IR and Raman spectral variations have revealed that the crystallinity of P(HB-co-HHx) (HHx = 12 mol%) decreases gradually from a fairly low temperature (about 60 T), while the crystallinity of PHB remains almost unchanged until just below its melting temperature. It has also been found from the IR and Raman studies that for both PHB and P(HB-co-HHx) the weakening of the C-H... 0 hydrogen bonds starts from just above room temperature, but the deformation of helical structures occurs after the weakening of the C-H... 0 hydrogen bonds advances to some extent. (c) 2004 Elsevier B.V. All rights reserved.Lead, ELSEVIER SCIENCE BV, Jun. 2005, JOURNAL OF MOLECULAR STRUCTURE, 744, 35 - 46, English[Refereed]Scientific journal
- Time-dependent infrared (IR) spectral variations during isothermal melt-crystallization process of poly(3-hydroxybutyrate) (PHB) have been analyzed for different wavenumber regions (C-H, C=O, C-O-C, and C-C stretching vibration regions) by difference spectra, second derivatives, and two-dimensional (2D) correlation analysis, and the bands characteristic of crystalline and amorphous parts are identified in each region. By the 2D correlation analysis, it has been found that the intensity changes in the 1731 cm(-1) band, which may be due to the intermediate state, and in the 1722 cm(-1) band due to the crystal packing occur out of phase with each other, whereas those in the two amorphous C=O stretching bands (1747 and 1739 cm(-1)) ascribed to the different conformations of the main chain are synchronous, which represents a cooperative conformational rearrangement for the C=O groups in the amorphous state during the crystallization process. Meanwhile, a distinct delay between the intensity change rates of bands at 1184 and 825 cm(-1) indicates that the adjustment of C-O-C backbone occurs faster than that of C-C backbone in PHB. This result has also been confirmed by investigating the 2D correlation spectra of PHB in various spectral regions. On the basis of these observations, a physical picture on the molecular evolution of PHB during the melt-crystallization process has been derived.AMER CHEMICAL SOC, May 2005, MACROMOLECULES, 38(10) (10), 4274 - 4281, English[Refereed]Scientific journal
- The isothermal crystallization processes of isotactic polystyrene at 160 degrees C from different initial states (quenched glassy state and melt state), i.e., cold- and melt-crystallization processes, have been investigated by infrared (IR) and generalized two-dimensional (2D) IR correlation spectroscopy. It has been found that not only the crystallization kinetics and crystallinity but also the sequential changes of the amorphous and crystalline sensitive bands are quite different for the cold- and melt-crystallization processes. This leads to the conclusion that the physical origins for spinodal decomposition prior to polymer crystallization may be different for different crystallization processes.AMER CHEMICAL SOC, Mar. 2005, JOURNAL OF PHYSICAL CHEMISTRY B, 109(12) (12), 5586 - 5591, English[Refereed]Scientific journal
- The nature of the "peculiarly strong" interaction between the poly(L-lactide) (PLLA) and poly(D-lactide) (PDLA) chains was investigated by real time infrared spectroscopy during the isothermal melt crystallization process of the PLLA/PDLA stereocomplex. A very small low-frequency shift (about 1 cm(-1)) of v(as)(CH3) and a larger low-frequency shift (about 5 cm(-1)) of v(C=O) were observed. The typical butterfly pattern in the two-dimensional (2D) asynchronous correlation spectrum and the second-derivative spectra reveal that there is a "peak shift" for v(C=0). The red shifts of the stretching vibration modes of the methyl and carbonyl groups suggest that the interaction between the PLLA/PDLA stereocomplex is ascribed to (CH3O)-O-...=C hydrogen bonding. Another interesting result is that the peak shift of the v(C=O) band already occurs in the induction period, which indicates that the (CH3O)-O-...=C interaction is the driving force for forming the racemic nucleation of the PLLA/PDLA stereocomplex. Moreover, the 2D correlation analysis indicates that the structural adjustment of the CH3 group occurs prior to that of the C-O-C backbone during the stereocomplexation process of PLLA/PDLA. The (CH3O)-O-...=C interaction may be the reason for this sequence of structural changes.AMER CHEMICAL SOC, Mar. 2005, MACROMOLECULES, 38(5) (5), 1822 - 1828, English[Refereed]Scientific journal
- The melting behavior of a bacterially synthesized biodegradable polymer, poly(3-hydroxybutyrate) (PHB), was investigated by using generalized two-dimensional infrared (2D IR) correlation spectroscopy. Temperature-dependent spectral variations in the regions of the C-H stretching (3100-2850 cm(-1)), C=O stretching (1800-1680 cm(-1)), and C-O-C stretching (1320-1120 cm(-1)) bands were monitored during the melting process. The asynchronous 2D correlation spectrum for the C=O stretching band region resolved two crystalline bands at 1731 and 1723 cm(-1). The intense band at 1723 cm(-1) may be due to the highly ordered crystalline part of PHB, and the weak band at 1731 cm(-1) possibly arises from the crystalline part with a less ordered Structure. These crystalline bands at 1731 and 1723 cm(-1) share asynchronous cross peaks with a band at around 1740 cm(-1) assignable to the C=O band due to the amorphous component. This observation indicates that the decreases in the crystalline components do not proceed simultaneously with the increase in the amorphous component. In the 3020-2915 cm(-1) region where bands due to the asymmetric CH3 stretching and antisymmetric CH2 stretching modes are expected to appear, eight bands are identified at 3007, 2995, 2985, 2975, 2967, 2938, 2934, and 2929 cm(-1). The bands at 2985 and 2938 cm(-1) are ascribed to the amorphous part while the rest come from crystal field splitting which is a characteristic of polymers with a helical structure. (C) Elservier B.V. All rights reserverd.PERGAMON-ELSEVIER SCIENCE LTD, Feb. 2005, SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY, 61(4) (4), 541 - 550, English[Refereed]Scientific journal
- Time-dependent infrared (IR) spectra were measured for isothermal melt-crystallization process of poly(L-lactide) (PLLA), poly (L-lactide)/poly(D-lactide) (PLLA/PDLA) stereocomplex, and poly(3-hydroxybutyrate) (PHB), and the spectra were analyzed for the C-H and C=O stretching band regions to explore the (CH3O)-O-...=C interactions in the above polymers. Both PI-A and PHB are well known biodegradable polymers and have similar chemical structures, however, they'showed quite different physical properties and spectral patterns in the C-H and C=O stretching band regions. For example, PLLA, the PLLA)PDLA stereocomplex and PHB, respectively, give a C=O stretching band due to the crystalline components at 1749, 1760, and 1723 cm(-1). The C=O stretching band of PLLA does not show a shift during the melt-crystallization process while that of the stereocomplex shows a 5 cm(-1) low-frequency shift. PLLA and the PLLA/PDLA stereocomplex yield a CH3 asymmetric stretching band at very similar positions (2997 and 2994 cm(-1) respectively), however. the former (the PLLA CH3 band) shows a 2 cm(-1) higher frequency shift during the melt crystallization, while the latter (the PLLA/PDLA- CH3 band) shows a 1 cm(- 1) lower frequency shift. PLLA and the stereo complex give only one CH3 asymmetric stretching band, while PHB shows four bands. One of the CH3 asymmetric stretching bands of PHB appears at an unusually high wavenumber (3007 cm(-1))- These marked differences in the C-H and C=O stretching band regions among PLLA. the PLLA/PDLA stereocomplex, and PHB suggest that they have different (CH3O)-O-...=C interactions. Based-on the detailed analysis of the C-H and C=O stretching band regions. we conclude that the PLLA/PDLA stereocomplex, and PHB have quite different types of C-(HO)-O-... hydrogen bonds in the crystalline, parts, and that PLLA has a only weak (CH3O)-O-...=C interaction. (C) 2004 Elsevier B.V. All rights reserved.ELSEVIER SCIENCE BV, Feb. 2005, JOURNAL OF MOLECULAR STRUCTURE, 735, 249 - 257, English[Refereed]Scientific journal
- Comparison of crystalline and lamella structure of PHB and it's copolymersThe crystalline structure and thermal behavior of biodegradable copolyester, Poly(hydroxyalkanoate) have been explored by means of wide-angle x-ray diffraction (WAXD) and infrared (IR) spectroscopy. It has been found from the WAXD pattern that P(HB-co-HV) is isomorphous crystal while only PHB is involved in the lamella structure of P(HB-co-HHx). This supports the results that PHB and P(HB-co-HV) keep crystalline structure untill near melting temperature, but P(HB-co-HHx) deform it from lower than the melting temperature.2005, Polymer Preprints, Japan, 54(1) (1), 1980, JapaneseInternational conference proceedings
- Structure, dispersibility and crystallinity of poly (hydroxybutyrate)/ poly(l-lactic acid) blends studied by FT-IR microspectroscopy and differential scanning calorimetryPoly(hydroxybutylate) (PHB) and poly(L-lactic acid) (PLLA) blends are prepared, and their spectra are measured by micro IR spectroscopy. Micro IR spectra obtained at different position of PHB/PLLA blends are quite different from each other. These results indicate that each component with different states exist in blends. DSC curves reveal that there are no changes in melting point and crystalline temperature of PHB.2005, Polymer Preprints, Japan, 54(2) (2), 3593, JapaneseInternational conference proceedings
- Infrared spectroscopy and X-ray diffraction study of structure and thermal behavior of unusual PHA; PHA with bulky substituent on its side chainIt has been explored from the X-ray diffraction patterns of PHPV and PHPxV, that PHPV is an amorphous polymer while PHPxV is a crystalline polymer. Temperature variation IR spectra of PHPxV showed the CH⋯O=C hydrogen bonding between the C=O group and CH of benzene, and it may because of this hydrogen bonding that PHPxV has the crystallinity though PHPV is entirely amorphous.2005, Polymer Preprints, Japan, 54(2) (2), 5341, JapaneseInternational conference proceedings
- Conformation rearrangement of poly(3-hydroxybutyrate) during the melt-crystallization process investigated by infrared and two-dimensional infrared correlation spectroscopyTime-dependent infrared (IR) spectral variations during isothermal melt-crystallization process of poly(3-hydroxybutyrate) (PHB) have been analyzed for different wavenumber regions (OH, C=O, C-O-C and C-C stretching vibration regions) by difference spectra, second derivatives and two-dimensional (2D) correlation analysis. Of particular note is that, in the C=O stretching region, a band at 1731 cm-1 due to an intermediate state between completely amorphous melt and fully developed ordered crystals in the melt-crystallization process is clearly detected in the second derivative spectra.2005, Polymer Preprints, Japan, 54(2) (2), 3121 - 3122, JapaneseInternational conference proceedings
- X-ray diffraction and infrared spectroscopy studies on crystalline and lamella structure of biodegradable polyhydroxyalkanoateThe crystalline structure and thermal behavior of biodegradable copolyester, Poly(hydroxyalkanoate) have been explored by means of wide-angle x-ray diffraction (WAXD) and infrared (IR) spectroscopy. It has been found from the temperature dependent variations of the WAXD pattern that C-H⋯O hydrogen bonding in the PHB lamella effect to chain folding and difference of their thermal behavior between PHB and P(HB-co-HHx).2005, Polymer Preprints, Japan, 54(1) (1), 603, JapaneseInternational conference proceedings
- The Adhesion Society of Japan, 2005, Journal of The Adhesion Society of Japan, 41(5) (5), 183 - 195, Japanese
- Two-dimensional (2D) correlation coefficient analysis is employed to classify and characterize spectral variations among heavily overlapped near-infrared spectra of pellets and films of three kinds of polyethylene (PE), high-density (HD), low density (LD), and linear low-density ( LLD) polyethylene, and five kinds of ivory signature seals. The sample-sample ( SS) 2D correlation maps are used for classification while the wavenumber-wavenumber (WW) 2D correlation maps are used for determining spectral variation among the above materials. Both correlation maps are obtained by multiplying the original data with themselves. It is found that the NIR spectra of pellets and films of HD PE are clearly different from those of LD PE and LLD PE, while the NIR spectra of five kinds of ivory seals yield easily discernable squares in the SS correlation maps. The background variation is thought to be behind the differentiation of the PE samples because the WW correlation maps do not indicate appearance of new bands. The correlation results are compared with those of principal component analysis (PCA). This study is a novel application of 2D correlation coefficient analysis which reveals that a comprehensive description of demanding spectral systems is achievable by utterly simple mathematical means because 2D correlation maps are obtained via a single mathematical operation.ROYAL SOC CHEMISTRY, 2005, ANALYST, 130(5) (5), 652 - 658, English[Refereed]Scientific journal
- The structure and thermal behavior of new types of bacterial copolyester, poly(3-hydroxybutyrate-co-3-hydroxyhexanoate); P(HB-co-HHx) (HHx=2.5, 3.4, and 12 mol %) have been explored by means of wide-angle x-ray diffraction (WAXD), differential scanning calorimetry (DSC), and infrared (IR) spectroscopy. The WAXD pattern of P(HB-co-HHx) (HHx=12 mol %) copolymer measured at room temperature has revealed that it has an orthorhombic system ( alpha = beta = gamma =90 degrees) with a=5.76A, b=13.2oA, c=5.96A (fiber repeat), which is identical to that of poly(3-hydroxybutyrate) (PHB). It has been found from the temperature-dependent variations of the WAXD pattern that only the a lattice parameter shows the thermal expansion, while the b lattice parameter changes little with temperature in the crystalline P(HB-co-HHx) (HHx=12 mol %). This observation suggests that there are inter and intramolecular interactions between C=O groups and alkyl groups along the a axis and that interactions are broken little by little with temperature. IR spectra were measured for the four kinds of polymers over a temperature range from 30 degrees C to high temperatures (200 degrees C; PHB, 180 degrees C; P(HB-co-HHx) (HHx=2.5 mol %), 180 degrees C; P(HB-co-HHx) (HHx=3.4 mol %), 150 degrees C; P(HB-co-HHx) (HHx=12 mol %)). Temperature-dependent IR spectral variations were analyzed for the CH, C=O, and C-O-C stretching band regions, and bands characteristic of crystalline and amorphous parts were identified in each region. It has been found from the IR study that the strength of interaction between the C=O group and the CH3 (or CH2) group is similar among the four polymers and that the population of C=O groups that are not involved in the interaction becomes higher with the increase in HHx. Both WAXD and IR studies have revealed that the crystallinity of P(HB-co-HHx) (HHx=12 mol %) decreases gradually starting from relatively low temperature (about 60 degrees C) while that of PHB remains high up to 170 degrees C.Lead, WILEY-V C H VERLAG GMBH, Jan. 2005, MACROMOLECULAR SYMPOSIA, 220, 123 - 138, English[Refereed]Scientific journal
- Molecular structure, crystallinity and morphology of uncompatibilized and compatibilized blends of high molecular weight polyethylene (HMWPE) and Nylon 12 were investigated by using Fourier-transform (FT) Raman spectroscopy, wide-angle x-ray diffraction (WAXD), and scanning electron microscopy (SEM). One of the important purposes of the present study is to compare the present results for HMWPE/Nylon 12 with the previously obtained results for high-density polyethylene (HDPE/Nylon 12). Uncompatibilized and compatibilized blends of HMWTE/Nylon 12 with a Nylon 12 content ranging from 10 to 90 wt% at increments of 10 wt% were prepared. The compatibilized polymer blends were prepared by adding a small amount of maleic anhydride (MAH), and SEM images show that the addition of the small amount of MAH (0.5 wt%) yields a marked improvement of dispersion of HMWPE and Nylon 12. To evaluate the crystallinity of HMWPE from Raman spectra, the relative intensities of bands at 1418 and 1129 cm(-1) to the intensity of a band at 1000 cm(-1) (I-1418/I-1000 and I-1129/I-1000) were estimated for all the uncompatibilized and compatibilized. blends of HMWPE/Nylon 12. From the comparison of the relative intensities (I-1418/I-1000 and I-1129/I-1000) between the uncompatibilized and compatibilized blends of HMWPE/Nylon 12 it was found that when the Nylon 12 content reaches 40 wt% the crystallinity of HMWPE in the compatibilized blends becomes higher than that of HMWPE in the uncompatibilized blends. The uncompatibilized and compatibilized blends of HMWPE/Nylon 12 (50/50) show quite different x-ray diffraction patterns; the compatibilized blend shows a significantly larger orientational effect in the x-ray pattern of HMWPE. It seems that the increase of interaction of MAH-HMWPE with the Nylon 12 matrix leads to the additional crystallinity.Lead, WILEY-V C H VERLAG GMBH, Jan. 2005, MACROMOLECULAR SYMPOSIA, 220, 75 - 83, English[Refereed]Scientific journal
- infrared (IR) spectra and wide-angle X-ray diffraction (WAXD) patterns of poly(3-hydroxybutyrate) (PHB) and its copolyester, poly(3-hydroxybutyrate-co-3-hydroxyhexanoate), P(HB-co-HHx) (HHx=12 mol%) were measured over a temperature range of 20 degrees C to higher temperatures (PHB, 185 degrees C, HHx = 12 mol%, 140 degrees C) to explore their structure change and thermal behavior and molecular interaction. The WAXD measurements revealed that the a lattice parameter increases significantly with temperature, while the b lattice parameter varies a little in the crystalline PHB and P(HB-co-HHx). it seems that the intermolecular interaction between the C=O group of one helical structure and the CH(3) group of the other helical structure decreases along the a axis of crystalline PHB and P(HB-co-HHx) with temperature. The temperature-dependent IR spectral variations were analyzed for the CH stretching, C=O stretching, CH(3) deformation, and C-O-C stretching variation regions, and bands characteristic of crystalline and amorphous parts were identified in each region. it was found from the anomalous frequencies of the CH(3) asymmetric stretching and C=O stretching bands of PHB and P(HB-co-HHx) and the X-ray crystallographic structure of PHB that there is an intermolecular interaction (C-H(...)O=C hydrogen bond) between the C=O group and the CH(3) group combining two helical structures in PHB and P(HB-co-HHx). in this review paper we discuss the role of the C-H(...)O=C hydrogen bonding and the crystal and lamella structure of PHB and P(HB-co-HHx) (HHx=12 mol %) in comparison with the structure of Nylon.Lead, WILEY-V C H VERLAG GMBH, 2005, MACROMOLECULAR SYMPOSIA, 230, 158 - 166, English[Refereed]Scientific journal
- The thermally induced crystalline/amorphous phase transition process of a newly developed biodegradable polymer. poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (P(HB-co-HHx)) (HHx = 12 mol%), was investigated by using generalized two-dimensional infrared (2D IR) correlation spectroscopy. Three spectral regions, the C-H stretching (3100-2800 cm(-1)), C=O stretching(1780-1680 cm(-1)), and C-O-C stretching (1330-1200 cm-1) band regions were analyzed in order to explore the phase transition behavior of the, copolymer. The asynchronous 2D spectrum generated from the temperature-induced variations in IR spectra in the C=O stretching band region clearly revealed the coexistence of two crystalline hands at 1731 and 1723 cm(-1). The dominant band at 1723 cm-1 may arise from the highly ordered crystalline component of the copolymer, and the weaker band at 1731 cm(-1) is possibly due to the minor crystalline component with a less ordered structure. The major crystalline band at 1723 cm(-1) shares asynchronous cross peaks with the amorphous band at 1740 cm(-1). This observation suggests that the melting of the crystalline structure does not simultaneously result in the formation of the completely amorphous structure. The phase transition process of P(HB-co-HHx) (12 mol% HHx) takes place through an intermediate state. It is noted that the vibrational frequencies of the C=O, C-O-C, and C-H stretching bands due to the crystalline components of P(HB-co-HHx) (12 mol%, Mix) are almost identical to those of PHB. These observations indicate that the helical structure of P(HB-co-HHx) (12 mol%. HHx) is very similar to that of PHB. The inclusion of the HHx comonomer locally disrupts the highly ordered and helical structure of PHB from place to place, thereby reducing the crystallinity of the copolymer. It was also found that the helical structure of P(HB-co-HHx) (12 mol% HHx) is deformed gradually from much lower temperature than that of PHB. (C) 2004 Elsevier B.V. All rights reserved.ELSEVIER SCIENCE BV, Dec. 2004, VIBRATIONAL SPECTROSCOPY, 36(2) (2), 241 - 249, English[Refereed]Scientific journal
- Crystallization behaviour of poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (P(HB-co-HHx)) (HHx = 12 mol%) was studied by means of two-dimensional infrared (2D IR) correlation spectroscopy. Three types of crystallization; the gradual cooling from the melt, the isothermal crystallization of the supercooled melt, and the isothermal crystallization of the solution-cast film were investigated. The order of crystal growth steps taking place during the three different types of crystallization processes was analyzed in detail. It was revealed by the asynchronous 21) correlation spectra generated from the dynamic IR spectra in the C=O stretching band region that the development of the highly ordered crystals occurs prior to that of the less ordered crystals for the gradual cooling crystallization. On the other hand, for the supercooled melt and solution-cast film crystallization, the formation of the less ordered crystals takes place before that of the highly ordered crystals. The transition from the amorphous phase to the less ordered crystals is a simultaneous process for all three types of crystallization. (C) 2004 Elsevier Ltd. All rights reserved.ELSEVIER SCI LTD, Sep. 2004, POLYMER, 45(21) (21), 7159 - 7165, English[Refereed]Scientific journal
- The surface melting and crystallization behavior of two biodegradable polyesters, poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (P(HB-co-HHx)) (HHx = 12 mol%) and poly(3-hydroxybutyrate) (PHB), were investigated by using attenuated total reflection (ATR) and transmission infrared (IR) spectroscopy coupled with the generalized two-dimensional (2D) correlation analysis. IR bands in the C=O stretching vibration region were analyzed to explore the changes in crystallinity at the surface and those in the bulk of the polymer film samples during the melting and crystallization processes. Due to the intrinsic sub-micrometer sampling depth of the ATR technique, spectral information attributed to the chemical moieties situated at the surface region of the film samples can be observed. The present study revealed that the surface melting of P(HB-co-HHx) takes place through an intermediate state. The distribution of crystalline phase detected by the ATR technique and that detected by the transmission technique suggested that the polymer crystals tend to grow at the surface in a manner different from that in the bulk. It is very likely that the population of polymer crystals at the surface is higher than that in the bulk for both P(HB-co-HHx) and PHB. The time-dependent IR spectral variations for P(HB-co-HHx) and those for PHB indicated that P(HB-co-HHx) crystallizes much slower than PHB. This observation suggested that the HHx units incorporated in P(HB-co-HHx) markedly reduce not only the degree of crystallinity but also the crystallization rate of PHB homopolymer. (C) 2004 Elsevier Ltd. All rights reserved.ELSEVIER SCI LTD, Sep. 2004, POLYMER, 45(19) (19), 6547 - 6554, English[Refereed]Scientific journal
- Infrared (IR) spectra of new types of bacterial copolyester, poly(3-hydroxybutyrate-co-3-hydroxyhexanoate), P(HB-co-HHx) (HHx = 2.5, 3.4, and 12 mol %), and poly(3-hydroxybutyrate) (PHB) were measured over a temperature range of 20 degreesC to higher temperatures (PHB, 185 degreesC; HHx = 2.5 mol %, 160 degreesC; HHx = 3.4 mol %, 160 degreesC; HHx = 12 mol %, 140 degreesC) to explore their structure and thermal behavior. The temperature-dependent IR spectral variations were analyzed for the CH stretching, C=O stretching, CH3 deformation, and C-O-C stretching vibration regions, and bands characteristic of crystalline and amorphous parts were identified in each region. It has been found from the anomalous frequencies of the CH3 asymmetric stretching bands of the four polymers and the X-ray crystallographic structure of PHB that there is an inter- or intramolecular interaction (C-(HO)-O-... hydrogen bond) between the C=O group in one helical structure and the CH3 group in the other helical structure in PHB and P(HB-co-HHx). The bonding energy of the C-(HO)-O-... hydrogen bond seems to be smaller than 4 kJ/mol, but considering the heat of fusion (12.5 kJ/mol) of PHB, it is likely that a chain of C-(HO)-O-... hydrogen bond pairs link two parallel helical structures in the crystalline parts. The temperature-dependent IR spectral variations have shown that the crystallinity of P(HB-co-HHx) (HHx = 12 mol %) decreases gradually from a fairly low temperature (about 60 degreesC), while the crystallinity of PHB and P(HB-co-HHx) (HHx = 2.5 and 3.4 mol %) remains almost unchanged until just below their melting temperatures. It has also been revealed from the present study that the weakening of the C-(HO)-O-... interaction starts from just above room temperature and proceeds gradually with increase in temperature, but the collapse of helical structure occurs at a much higher temperature for all the polymers investigated.Lead, AMER CHEMICAL SOC, Sep. 2004, MACROMOLECULES, 37(19) (19), 7203 - 7213, English[Refereed]Scientific journal
- The thermal behavior and molecular interaction of a new type of bacterial copolyester, poly(3-hydroxybutyrate-co-3-hydroxyhexanoate), P(HB-co-HHx) (HHx = 12 mol %), was investigated by using wide-angle X-ray diffraction (WAXD) and differential scanning calorimetry (DSC). The WAXD measurements were carried out over a temperature range from 25 to 110 degreesC in the scattering angle range of 20 = 5-13degrees. The WAXD pattern at room temperature shows that the P(HB-co-HHX) copolymer has an orthorhombic system (alpha = beta = gamma = 90degrees) with a = 5.76 Angstrom, b = 13.20 Angstrom, and c = 5.96 Angstrom (fiber repeat), which is identical to the crystal system of poly(3-hydroxybutyrate) (PHB) homopolymer. However, temperature-dependent variations in the lattice parameters, a and b, of P(HB-co-HHx) are quite different from those of PHB. Only the a lattice parameter increases with temperature, while the b lattice parameter changes very little in the case of crystalline P(HB-co-HHx). It seems that the intermolecular and intramolecular interactions between the C=O group and the CH3 group decrease along the a axis of crystalline P(HB-co-HHx) with temperature. The (110) peak area of P(HB-co-HHx) starts decreasing from around 50 degreesC while that of PHB changes little at least until 140 degreesC, indicating that the crystallinity of PHB remains almost unchanged until 140 degreesC, but that of P(HB-co-HHx) decreases gradually from fairly low temperature (similar to50 degreesC). The DSC measurement of the chloroform solution cast P(HB-co-HHx) shows a recrystallization peak around 51 degreesC. The (110) peak area of WAXD pattern of the chloroform solution cast P(HB-co-HHx) shows a maximum value at around 54 degreesC. The maximum of the (110) peak area demonstrates the recrystallization process of P(HB-co-HHx). The result is in a good agreement with the result of the DSC measurement.AMER CHEMICAL SOC, May 2004, MACROMOLECULES, 37(10) (10), 3763 - 3769, English[Refereed]Scientific journal
- Our recently proposed idea of moving window two-dimensional (2D) correlation spectroscopy, which partitions a data set into series of relatively small submatrices (windows) and calculates their covariance maps in succession, is tested for three convoluted data set. Phase-transition temperatures of oleic acid and poly-(N-isopropylacrylamide) in an aqueous solution are sought by analyzing covariances of their temperature-dependent near-infrared and infrared spectra, respectively, while Raman spectra of three kinds of polyethylene (PE) pellets are investigated to find the spectral differences among them and to classify randomly ordered spectra by a sample-sample (SS) covariance map. The criterion of mean of standard deviation of covariance matrices is used as an indicator of the crucial information present in these matrices so that only a few of them are discussed in details. The results are obtained quickly after very simple calculations and are studied at length. The baseline variation is not removed prior to the calculations but is found to be of use for the determination of the phase-transition temperatures. Randomly ordered Raman spectra of the PE pellets are classified by innovatively used and interpreted SS slice spectra, with the relation to principal component analysis discussed.AMER CHEMICAL SOC, Aug. 2003, ANALYTICAL CHEMISTRY, 75(16) (16), 4010 - 4018, English[Refereed]Scientific journal
- Lead, Apr. 2003, Macromol. Chem. Phys., 204, 1351 - 1358, EnglishMolecular Structure, Crystallinity, and Morphology of Uncompatibilized and Compatibilized Blends of Polyethylene/Nylon 12[Refereed]Scientific journal
- A simple method that facilitates analysis of chemical images is presented. It is based on so-called two-dimensional (2D) correlation spectroscopy and its main purpose is to identify the most specific spectra in an imaging set. The selection is achieved by measuring correlation among the spectra via sample-sample (SS) correlation technique. The idea of SS correlation is exemplified through a simple model and then applied to the mapping Raman spectra of compatibilized (a mixture of two polymers is made homogenous thereby improving its useful plastic properties) and uncompatibilized (mechanically blended) blends of Nylon 12/high-density polyethylene (HDPE), and poly(ethyleneterephthalate)(PET)/HDPE. The Raman spectra of the blends are analyzed with and without pre-treatments (baseline correction by an nth order polynomial, and normalization), and it is found that the results are significantly dependent on the pre-treatment. It is concluded that all the analyzed blends do not exhibit band-shape variation despite the compatibilization, but appear to have unique vibrational signatures, i.e. each blend is found to be completely represented by only one spectrum. The sensitivity of the employed SS correlation method is illustrated through making distinction among heavily overlapped spectra differing minutely in the baseline.ROYAL SOC CHEMISTRY, 2003, ANALYST, 128(8) (8), 1097 - 1103, English[Refereed]Scientific journal
- Near infrared spectra of pellets and thin films of high-density, low-density and linear low-density polyethylenes and prediction of their physical properties by multivariate data analysisThe aim of the present study is to investigate in detail the near infrared (NIR) spectra of the three types of polyethylene, linear low-density polyethylene (LLDPE), low-density polyethylene (LDPE) and high-density polyethylene (HDPE), and to develop calibration models that predict their physical properties such as density, crystallinity and melting point. The effects of spectral resolution on the classification and the prediction of density for the three types of PE have been investigated. Furthermore, the NIR spectral differences among LLDPE, LDPE and HDPE have been explored in more detail using 2 cm(-1) resolution. Principal component analysis (PCA) has been performed to differentiate the 18 samples of PE. They are classified into three groups, LLDPE, LDPE and HDPE, by a score plot of the PCA Factor 1 versus 3 based on the NIR spectra pretreated by multiplicative scatter correction (MSC). The 2 cm(-1) spectral resolution yields a slightly better result for the classification. Partial least squares (PLS) regression has been applied to the NIR spectra after MSC to propose calibration models that predict the density, crystallinity and melting point of HDPE, LDPE and LLDPE. The correlation coefficient for the density was calculated to be 0.9898, 0.9928, 0.9925 and 0.9872 for the spectra obtained at 2, 4, 8 and 16 cm(-1) resolutions, respectively, and the root mean square error of cross validation (RMSECV) was found to be 0.0021, 0.0018, 0.0018 and 0.0023 g cm(-3), respectively. It has been found that the correlation coefficient and RMSECV for the prediction of the density and crystallinity change little with the spectral resolution. However, for the prediction of melting point, the higher resolutions (2 and 4 cm(-1) resolution) provide slightly better results than the lower resolutions. NIR transmission spectra of thin films of LLDPE, LDPE and HDPE have also been investigated, and calibration models for predicting their density have been developed for the film spectra.Lead, N I R PUBLICATIONS, 2003, JOURNAL OF NEAR INFRARED SPECTROSCOPY, 11(4) (4), 309 - 321, English[Refereed]Scientific journal
- Raman spectra have been measured for pellets of five samples of high-density polyethylene (HDPE), seven samples of low-density polyethylene (LDPE), and six samples of linear low-density polyethylene (LLDPE). The obtained Raman spectra have been compared to find out characteristic Raman bands of HDPE, LDPE, and LLDPE. Principal component analysis (PCA) was applied to the Raman spectra in the 1600-650 cm(-1) region after multiplicative scatter correction (MSC) to discriminate the Raman spectra of the three different PE species. They are classified into three groups by a score plot of PCA factor 1 vs. 2. HDPE with high density and high crystallinity gives high scores on the factor I axis, while LDPE with low density and low crystallinity yields negative scores on the same axis. It seems that factor I reflects the density or crystallinity. A PC weight loadings plot for factor I shows six upward peaks corresponding to the bands arising from the crystalline parts or all-trans -(CH2)(n)- groups and seven downward peaks ascribed to the bands of the amorphous or anisotropic regions and those arising from the short branches. Partial least-squares (PLS-1) regression was applied to the Raman spectra after MSC to propose calibration models that predict the density, crystallinity, and melting points of the polyethylenes. The correlation coefficient was calculated to be 0.9941, 0.9800, and 0.9709 for the density, crystallinity, and melting point, respectively, and their root-mean-square error of cross validation (RMSECV) was found to be 0.0015, 3.3707, and 2.3745, respectively. The loadings plot of factor 2 for the prediction of melting point is largely different from those for the prediction of density and crystallinity. (C) 2002 Wiley Periodicals, Inc.JOHN WILEY & SONS INC, Oct. 2002, JOURNAL OF APPLIED POLYMER SCIENCE, 86(2) (2), 443 - 448, English[Refereed]Scientific journal
- Raman mapping study of compatibilized and uncompatibilized polymer blends of Nylon 12 and polyethyleneRaman mapping images have been obtained for compatibilized and uncompatibilized polymer blends in films of Nylon 12 and high density polyethylene (HDPE) (blend ratios were 20/80, 50/50, and 80/20). A total of 400 Raman spectra were measured for each sample with areas of 100 mum(2) and in step sizes of 0.5 mum (for 20 X 20 probe spots). To develop the Raman mapping images, the intensity ratio of two bands, a band at 1635 cm(-1) due to Nylon 12 (amide I mode) and that at 1296 cm(-1) arising from both HDPE and Nylon 12 (CH2 twisting) is used. The Raman mapping images of the uncompatibilized polymer blends show a clear "sea-island" structure while those of the compatibilized polymer blends exhibit a compatibilized structure. The Raman mapping images enable simultaneous exploration of the morphology and molecular structure of the blends. We have also developed a Raman mapping image that represents the variation of crystallinity in the uncompatibilized film.SOC APPLIED SPECTROSCOPY, Aug. 2002, APPLIED SPECTROSCOPY, 56(8) (8), 1038 - 1043, English[Refereed]Scientific journal
- A conformational change in the coil-globule transition of poly(N-isopropylacrylamide) (PNiPA) was investigated by Fourier transform infrared (FT-IR) spectroscopy with attenuated total reflection (ATR) method and density functional theory (DFT) calculations. ATR/IR spectra of PNiPA in an aqueous solution change dramatically in the vicinity of the coil-globule transition temperature (theta temperature). Below the theta temperature, unimodal peaks are observed at 1624 cm(-1) in the amide I re ion and at 1562 cm(-1) in the amide II region, respectively. Above the theta temperature, a new peak appears abruptly near 1653 cm(-1) in the amide I region and the amide If band shifts gradually to a lower frequency by 6 cm(-1). In the amide III region, the relative intensity of a band at 1173 cm(-1) is weaker than that of a band at 1155 cm(-1) at lower temperatures, but it becomes larger during the coil-globule transition of PNiPA. DFT calculation for dimer models of PNiPA suggests that the amide I band at 1624 cm(-1) is assigned mainly to a stretching vibration of the C=O group that forms a strong hydrogen bond with the N-H bond of a neighboring amide group. The band at 1653 cm(-1) observed above the theta temperature may be due to a free C=O group. It is, therefore, suggested that some of the intramolecular hydrogen bonds between neighboring amide groups are broken during the coil-globule transition. Furthermore, it is deduced from the DFT calculation that the relative intensity of the bands at 1173 and 1155 cm(-1) in the amide III region reflects the population change in the gauche and trans conformations in the main chain during the coil-globule transition.AMER CHEMICAL SOC, Apr. 2002, JOURNAL OF PHYSICAL CHEMISTRY A, 106(14) (14), 3429 - 3435, English[Refereed]Scientific journal
- Near-infrared spectroscopic study of interaction between methyl group and water in water-methanol mixturesNear-infrared spectra were measured for water-methanol mixtures with a methanol content of 0-100 wt % at 25 degreesC. The second derivative of the NIR spectra clearly reveals that the first overtones of the CH3 asymmetric stretching modes of methanol near 5950 and 5900 cm(-1) show a downward shift by about 30 cm(-1) with the increase in the concentration of methanol. This is unambiguous evidence for the direct interaction of the CH3 group of methanol with the OH group of water. Similar downward shifts were also observed for water-ethanol and water-l-propanol mixtures, although the shifts are much smaller for the water-ethanol and water-1-propanol mixtures. Based upon the results of NIR spectra, we propose a model for the interaction between the C-H bond of the CH3, group of methanol and water. This Intermolecular interaction is analogous to the intramolecular "(O) CH (...) O" interaction in compounds having both a CH3 group binding to an oxygen atom and an OH group. This paper demonstrates novel potential of NIR spectroscopy in investigating interactions containing a C-H bond.SOC APPLIED SPECTROSCOPY, Mar. 2002, APPLIED SPECTROSCOPY, 56(3) (3), 357 - 361, English[Refereed]Scientific journal
- The crystallinity of non-molten and pre-molten uncompatibilized and compatibilized polymer blends of high density polyethylene (HDPE)/Nylon 12 have been investigated by using FT-Raman spectroscopy, differential scanning calorimetry (DSC), and wide angle X-ray diffraction (WAXD). The FT-Raman, DSC, and WAXD measurements have revealed that the crystallinity of HDPE of both uncompatibilized and compatibilized blends increases upon melting except for the compatibilized blend with the Nylon 12 content of 80 wt%. The degree of the increase is significantly larger for the uncompatibilized blends than the compatibilized blends. The FT-Raman data suggests that the crystallinity of the compatibilized blend with the Nylon 12 content of 80 wt% decreases slightly after melting. It is very likely that the compatibilized polymer blends are well oriented during the melting and molding process by an extruder because of the existence of maleic anhydride (MAH)-grafted copolymer as a compatibilizer. In contrast, it seems that the uncompatibilized polymer blends are not so much oriented and have more amorphous phase in the Nylon 12 rich region before melting. Thus, the melting process induces a recrystallization process.Lead, 2002, Macromolecular Symposia, 184, 339 - 348, English[Refereed]International conference proceedings
- Usefulness of a curve fitting method in the analysis of overlapping overtones and combinations of CH stretching modesThis paper reports the usefulness of a curve fitting method in the analysis of NIR spectra. NIR spectra in the 7500-5500 cm(-1) (1333-1818 nm) region were measured for water-methanol, water-ethanol and water-1-propanol mixtures with alcohol concentrations of 0-100 wt% at 25degreesC. The 6000-5600 cm(-1) (1667-1786 nm) region, where the overtones and combinations of CH3 and CH2 stretching modes are expected to appear, shows significant band shifts with the increase in the alcohol content. To analyse the concentration-dependent spectral changes, a curve fitting method was utilised, and the results were compared with those obtained previously by a second derivative method. It was found that the first overtones of CH3 asymmetric and symmetric stretching modes of alcohols show a downward shift by about 15-30 cm(-1) with the increase in the concentration of alcohols. The shifts are much larger for water-methanol mixtures than for water-ethanol and water-1-propanol mixtures. The first overtones and combinations of CH2 stretching modes of ethanol and 1-propanol also show a small downward shift. These shifts support our previous conclusion that there is an intermolecular "CH...O" interaction between the methyl group and water in the water-alcohol mixtures. The curve fitting method provided more feasible results for the band shifts than the second derivative method. It was revealed from the curve fitting method that the first overtone of the CH3 asymmetric stretching mode of water-methanol, water-ethanol and water-1-propanol mixtures shows different concentration-dependent plots. The first overtone of CH3 asymmetric stretching mode of water-methanol mixtures shifts more rapidly in the high methanol concentration range while that of water-1-propanol concentration shifts more markedly in the low 1-propanol concentration range. That of water-ethanol mixtures shows an intermediate trend. Based upon these differences structural differences among the three kinds of water-alcohol mixtures are discussed.N I R PUBLICATIONS, 2002, JOURNAL OF NEAR INFRARED SPECTROSCOPY, 10(1) (1), 85 - 91, English[Refereed]Scientific journal
- A self-assembled monolayer film (SAM) of 2,3,7,8,12,13,17, 18-octaethylporphinatozinc formed on a gold surface premodified with a SAM of 4-pyridinethiol was studied by means of surface-enhanced Raman scattering (SERS), surface-enhanced infrared absorption (SEIRA), and ultraviolet-visible (UV-vis) spectroscopies. The SERS spectrum of the porphyrin monolayer on the pyridine-modified Au surface shows bands only from the underlying pyridine group. The frequency shift and change in the relative intensity of the bands due to the pyridine group in the SERS spectra imply indirectly the binding of the metalloporphyrin to the pyridine group in the SAM. This is further supported by the SEIRA spectra of the porphyrin-pyridine SAM, in which vibrational bands arising from both the porphyrin moiety and the pyridyl group appear clearly. In addition, the UV-vis spectra also suggest the formation of the porphyrin-pyridine SAM and the weak porphyrin-porphyrin interactions in the SARI.AMER CHEMICAL SOC, Jul. 2001, LANGMUIR, 17(15) (15), 4564 - 4568, English[Refereed]Scientific journal
- 化学工業社, May 2001, 化学工業, 52(5) (5), 393 - 405, Japanese複雑な分子スペクトルをいかに解析するか-振動スペクトルを例として-(2)Scientific journal
- Apr. 2001, 化学工業, 52, 268-292, Japanese複雑な分子スペクトルをいかに解析するか-振動スペクトルを例として-(1)Scientific journal
- Dispersed rheology of lipophilized-smectite (SAN)/toluene (TOL) suspensions with various concentrations φ of (0.03-3.77) × 10-2 vol fraction was examined by a stress-controlled rheometer and Ubbelohde type viscometer. Under the quiescent state of the SAN/TOL suspensions, the original laminate structure in the solid state of SAN was lost and exfoliation of the silicate layers took place as revealed by X-ray diffraction analysis. In the dilute SAN/TOL suspension with 102φ ≤ 0.2, the value of ηsp/φ (ηsp being specific viscosity) is independent of concentration up to φ approx. 2 × 10-3 and exhibits abrupt increasing beyond φ approx. 2 × 10-3. The dense concentration region exhibits elastic gel-like properties, and rheopexy behavior imposed by shear stress was observed. The limiting value of the dynamic storage modulus G′ was given by G′(ωYLD0) approx. φ4, whereas the loss tangent δ exhibited independence of φ and remains at a constant value of about 0.1.ACS, May 2000, Langmuir, 16(9) (9), 4055 - 4058, English[Refereed]Scientific journal
- Apr. 2000, Langumuir, 17, 4564 - 4568, EnglishDispersed Structure and Rheology of Lipophilized-Smectite/Toluene Suspensions[Refereed]Scientific journal
- Society of Rheology, 2000, Nihon Reoroji Gakkaishi, 28(4) (4), 199 - 200, English[Refereed]Scientific journal
- Phase separation process during solution casting of acrylate-copolymer/fluoro-copolymer blendsFor the P(2EHA-AA-VAc)/P(VDF-HFA)/THF ternary system, the phase separation process during solution casting was examined via Rayleigh scattering measurement. The scattered intensity of the scattering vector q at various times for the P(2EHA-AA-VAc)/P(VDF-HFA) 30/70 blend having a gradient domain morphology revealed that the gradient structure formed according to both spinodal decomposition (SD) and nucleation growth (NG) mechanisms.TAYLOR & FRANCIS LTD, 1999, JOURNAL OF ADHESION SCIENCE AND TECHNOLOGY, 13(11) (11), 1243 - 1251, English[Refereed]Scientific journal
- Rayleigh scattering studies were conducted in order to examine the elongational flow-induced crystallization behaviour of poly(ethylene terephthalate) (PET) in the supercooled liquid state (100-130°C). In the specimen elongated at 110°C where spherulite growth was negligible, initially nothing happened, but flow-induced crystallization then occurred rather suddenly at a critical tensile strain of ∈(= ∈̇0t) ≈ 2 in Hencky units, independent of the strain rate ∈̇0. At this temperature the Hv (cross-polarized) scattering yielded two-point patterns parallel to the elongational direction with strong streaks in the perpendicular direction. The result implies that molecular orientation proceeded along the flow direction and the crystalline domain grew transverse to the oriented chains. In contrast, at 130°C, especially with low ∈̇0, where spherulite growth was rapid, a four-leaf-clover pattern typical of spherulites was observed at the start of elongation ∈ = 0. In the following stages, spherulite growth surpassed the destruction of existing spherulites and/or flow-induced oriented crystallite formation, and a smeared four-leaf-clover pattern was thus observed even at a level of ∈ = 1.3. © 1997 Elsevier Science Ltd.Elsevier BV, 1998, Polymer, 39(2) (2), 501 - 503, English[Refereed]Scientific journal
- Nondestructive discrimination of biological materials by near-infrared Fourier transform Raman spectroscopy and chemometrics: Discrimination among hard and soft ivories of African elephants and mammoth tusks and prediction of specific gravity of the ivoriesThis paper demonstrates the usefulness of near-infrared (NIR) Fourier transform (FT) Raman spectroscopy and chemometrics in nondestructive discrimination of biological materials. The discrimination among three kinds of materials-hard ivories, soft ivories, and mammoth tusks-has been investigated as an example. NIR (1064-nm) excited FT-Raman spectra were measured in situ for these materials, and principal component analysis (PCA) of the obtained spectra was carried out over the 1800-400-cm(-1) region. The two kinds of ivories are clearly discriminated from one another on the basis of a one-factor plot. It was found that treatment of the Raman data by multiplicative scatter correction (MSC) greatly improves the ability to discriminate. Principal component weight loadings show that the discrimination relies upon the ratio of collagen and hydroxyapatite included in two kinds of ivories. The discrimination among the hard and soft ivories and mammoth tasks was made by a three-factor plot for FT-Raman spectra after the MSC treatments. Partial least-squares regression (PLSR) enabled us to make a calibration model which predicts the specific gravity of the hard and soft ivories.SOC APPLIED SPECTROSCOPY, Aug. 1997, APPLIED SPECTROSCOPY, 51(8) (8), 1154 - 1158, English[Refereed]Scientific journal
- Critical behavior in a polymer blendStatic and dynamic critical behaviors were studied for a mixture of polydimethylsiloxane (M(w) = 1.91 x 10(4), M(w)/M(n) < 1.03) and polyethylmethylsiloxane (M(w) = 1.40 x 10(4), M(w)/M(n) < 1.02) using coexistence curve, turbidity, light scattering, and viscosity measurements. The critical point was determined precisely from the coexistence curve as the critical composition W-c,W-PEMS = 55.04 wt% and the critical mixing temperature T-c = 30.622 degrees C. The critical exponents for the shape of the coexistence curve (beta), the osmotic compressibility (gamma), the long-range correlation length (nu), the correction for the static correlation function (eta), and the shear viscosity (phi) are 0.327+/-0.003, 1.25+/-0.02, 0.63+/-0.02, 0.038+/-0.003, and 0.029+/-0.003, respectively, with xi(0) = 1.62+/-0.05 nm. The present critical polymer blend belongs to the universality class of the three-dimensional Ising model, similar to simple binary liquid mixtures. The crossover from Ising to mean-field behavior was not observed, and this observation is consistent with the crossover function of recent theoretical work. A clear shear effect on the viscosity was observed near the critical point. The critical part of the diffusion coefficient is rather well represented by the dynamic scaling function based on mode coupling theory, confirming the validity of the dynamic scaling concept for the polymer blend.Lead, AMERICAN PHYSICAL SOC, Apr. 1996, PHYSICAL REVIEW E, 53(4) (4), 3854 - 3863, English[Refereed]Scientific journal
- The coexistence curve of poly(dimethylsiloxane) (Mw=1.91×104,Mw/ Mn< 1.03) and poly(ethylmethylsiloxane) (Mw=1.40×104,Mw/Mn< 1.02) was determined in the neighborhood of its critical point with a differential refractometer. The critical mixing point established by the coexistence curve was Tc=30.622±0.005 °C and Wc,PEMS=55.04±0.04 wt %. The coexistence curve near the critical mixing point could be fitted well by a critical exponent β of 0.327. The turbidity could also be fitted by using ν=0.65 for the correlation length and γ=1.20 for the osmotic compressibility, showing the three-dimensional Ising model universality. © 1995 The American Physical Society.1995, Physical Review Letters, 75(8) (8), 1534 - 1537, English[Refereed]Scientific journal
- LIGHT-SCATTERING STUDY OF THE SWELLING PROCESS OF POLY(ACRYLONITRILE-CO-BUTENE)-GRAFT-POLY(ACRYLONITRILE-CO-METHYLACRYLATE) FILMThe time evolution of the size and density of the swollen domains during the swelling of poly(acrylonitrile-co-butene)-graft-poly(acrylonitrile-comethylacrylate) film in methanol was studied by light scattering measurements. The observed scattered light intensity was analyzed by the Guinier plot. The time evolution of the mean radius R(t)BAR and number density N(t) of the swollen domains was given R(t)BAR3 approximately t0.12 N(t) approximately t1.42.JOHN WILEY & SONS LTD, Nov. 1994, POLYMER INTERNATIONAL, 35(3) (3), 219 - 224, English[Refereed]Scientific journal
- PHASE-SEPARATION IN A DILUTE POLYMER-SOLUTION IN A METASTABLE REGIONThe time evolution of phase separation in a supercooled dilute polymer solution (polystyrene in diethyl oxalate) in a metastable region was studied by time-resolved dynamic and static light scattering. The mean radius R(t) and the total number density N(t) of droplets consisting of the minority phase were obtained as R(t)similar to t(1) and N(t)similar to t(0) in the growth stage, and as R(t)similar to t(1/3) and N(t)similar to t(-1) in the coarsening stage.Lead, AMER PHYSICAL SOC, Sep. 1994, PHYSICAL REVIEW E, 50(3) (3), R1752 - R1754, English[Refereed]Scientific journal
- CRITICAL-BEHAVIOR OF A CATIONIC SURFACTANT IN AN AQUEOUS SALT SOLUTIONThe critical behavior of a cationic surfactant, butyl-tetradecyldimethylammonium bromide, in an aqueous 4M-NaBr solution was investigated concerning the isothermal osmotic compressibility and long-range correlation length by means of light scattering, coexistence curve, and turbidity. The critical exponents were obtained as gamma'=1.39+/-0.04 and nu'=0.70+/-0.03 together with xi(0)= (2.48+/-0.06) nm, and beta' = 0.375+/-0.01. The temperature dependence of turbidity showed a good accordance with the result of light scattering measurement. Negative alpha' was obtained from the scaling relation. The critical exponents are in good agreement with the Fisher-renormalization prediction for the ternary system (almost fully renormalized Ising exponents).AMER INST PHYSICS, Mar. 1994, JOURNAL OF CHEMICAL PHYSICS, 100(6) (6), 4543 - 4547, English[Refereed]Scientific journal
- The time evolution of phase separation in a supercooled dilute polymer solution (polystyrene in diethyl oxalate) in a metastable region was studied by time-resolved dynamic and static light scattering. The mean radius R(t) and the total number density N(t) of droplets consisting of the minority phase were obtained as R(t)t1 and N(t)t0 in the growth stage, and as R(t)t1/3 and N(t)t-1 in the coarsening stage. © 1994 The American Physical Society.1994, Physical Review E, 50(3) (3), R1752 - R1754, English[Refereed]Scientific journal
- CONCENTRATION FLUCTUATION IN A POLYMER MIXTUREThe critical behavior in a mixture of polystyrene and polymethylphenylsiloxane has been examined by the angular distribution of the scattered light intensity over 5.7 < k < 19.6 mum-1 and 0.045 < T- T(c) < 2.4-degrees-C, where k is the scattering wave number and T(c) is the critical mixing temperature. The osmotic compressibility obeys a relation chi(T) approximately (T-T(c))-gamma with gamma=1.22+/-0.02 and the long-range correlation length xi approximately (T-T(c))-nu with nu=0.62+/-0.02, in good agreement with the three-dimensional Ising-model universality.AMERICAN PHYSICAL SOC, Oct. 1993, PHYSICAL REVIEW E, 48(4) (4), 3176 - 3179, English[Refereed]Scientific journal
- KINETICS OF SPINODAL DECOMPOSITION IN A POLYMER MIXTUREThe early-to-late stage of spinodal decomposition in a critical mixture of polystyrene and polymethylphenylsiloxane was studied by time-resolved light scattering over 1.8 < k < 21.1 mum-1 and 0 < t < 502 h, with k and t being the wave number and the elapsed time after temperature quench into the spinodal region, respectively. The time dependences of the maximum intensity of the scattered light I(m) and of the corresponding wave number k(m) were represented by the power laws; I(m) is-proportional-to t(beta) and k(m) is-proportional-to t(-alpha) with alpha = 0 in the early stage, alpha = 0.17 in the intermediate stage, and beta = 1.08 and alpha = 0.36 satisfying beta = 3alpha in the late stage. The behavior in the early stage was well expressed by the Cahn-Hillard theory. These exponent values are almost the same as those observed for Fe-Cr alloys. The behavior of the scaled structure factor in the late stage was expressed by a k-6 dependence in k(m) < k < 2k(m) and by a k-4 dependence in k > 2k(m), in good agreement with the recent theoretical prediction.AMERICAN PHYSICAL SOC, Feb. 1993, PHYSICAL REVIEW E, 47(2) (2), 1132 - 1138, English[Refereed]Scientific journal
- 1992, The Journal of Chemical Physics, 97(8) (8), 5905 - 5907, English[Refereed]Scientific journal
- 2024, Journal of Fiber Science and Technology, 80(3) (3), 109 - 112
- Infrared, Raman, and near-infrared spectroscopy are well known as vibrational spectroscopy methods, and recently, in addition to these methods, terahertz (THz) and low-frequency Raman spectroscopy have been used in a variety of fields. THz and low-frequency Raman spectroscopy mainly deal with the region below 300 cm-1. Since molecular skeletal and intermolecular vibrations are observed, and the spectra observed in these regions are very sensitive to the higher-order structure of polymer compounds and intermolecular interactions. Recently, authors have attempted to study the higher-order structures and intermolecular interactions of semi-crystalline polymers and biodegradable polymers as well as low-frequency imaging and marine degradation processes of polymers. Here, we present some applications of these vibrational spectroscopic techniques to polymers.The Society of Polymer Science, Japan, 2024, POLYMERS, 73(6) (6), 267 - 268, Japanese
- Tetrabutylammonium/phosphonium bromide (TBAB/TBPB) hydrates, ionic clathrate hydrates were investigated by low frequency Raman scattering including in Terahertz (THz) region. The peak position and full-width-half-maximum (FWHM) of each hydrate were compared in the region below 3 THz (100 cm-1) . The position of the peak considered to be the translational movement of the anion was about 65 cm-1 in TBAB, which was clearly higher than TBPB. This is considered to be due to difference of contribution to center cation in atomic charge distribution. In addition, FWHM is may be due to the crystal structure and reflects the interaction between the anion and the water molecule. Direct observation of intermolecular interactions using spectroscopy in the terahertz region can be used to assess the influence of guest molecule differences on material characteristics.The Japan Institute of Energy, 31 Jul. 2019, Proceedings of the Annual Conference of The Japan Institute of Energy, 28, 58 - 59, Japanese
- Terahertz(THz) spectroscopy is a powerful tool that uses the low-frequency vibrational modes to elucidatethe intermolecular interaction and the higher order structure of polymers. THz spectroscopy is suitedfor investigating polymer structures because it is very sensitive to the long range structure of large molecules,which is closely related to their physical properties. However, the band assignment of THz spectra of polymershas not been studied well. The present study aims to explore further information about inter- and intramolecularinteractions of polymer materials by THz spectroscopy with the aid of infrared(IR), low-frequencyRaman spectroscopy, quantum chemical calculations(QCCs) and natural bond orbital(NBO) calculations. Inaddition, THz imaging makes it possible to explore the higher order structure of a sample without altering ordestroying it. In the present study, we have also investigated the characterization of polymer film by THz imaging.Consequently, THz imaging using the intensity ratio of the two spectral peaks at 47 and 67 cm-1 was ableto evaluate the distribution of crystallinity of PCL films. Therefore, THz spectroscopy was shown to be a goodmethod for easy monitoring of inter- and intramolecular hydrogen bondings in the polymer.The Adhesion Society of Japan, 01 Oct. 2018, Journal of The Adhesion Society of Japan, 54(10) (10), 381 - 388, Japanese
- 2018, 日本分光学会年次講演会, 2018ATR-FUV分光法を用いた高分子電解質に関する電子状態と結晶相変化の相関
- The Physical Society of Japan, 2016, Meeting Abstracts of the Physical Society of Japan, 71, 1354 - 1354, Japanese
テラヘルツ周波数領域には高分子特有の振動モードが存在しており、テラヘルツ光を用いた高分子材料の物性測定に、注目が集まっている。我々は高分子ポリ乳酸薄膜を延伸することで、ポリ乳酸に複屈折が生じることを発見した。また、複屈折の延伸率依存性をテラヘルツ帯の回転検光子型偏光計で調べた。さらにテラヘルツ時間領域分光法を用いて、延伸ポリ乳酸薄膜の複素屈折率が持つ偏光依存性を調べた。
- Birefringent properties of poly-lactic acid at terahertz rangeWe report on a drawing-ratio dependence of the refractive index difference between the two optic axes (Delta n) of poly lactic acid films in terahertz frequency range. We found that Delta n can be controlled in a range of 0-0.04 by changing the drawing ratio. The result shows that we can design a terahertz wave plate with arbitral retardation, which will be useful for establishing polymer-based terahertz optical component with low cost and easy implementation in mass production.IEEE, 2016, 2016 41ST INTERNATIONAL CONFERENCE ON INFRARED, MILLIMETER, AND TERAHERTZ WAVES (IRMMW-THZ), English[Refereed]
- 2012, 分子科学討論会講演プログラム&要旨(Web), 6th減衰全反射遠紫外分光法によるナイロン極表面の電子状態の研究
- Terahertz absorption spectra were measured for nylon-6/6, nylon-6, nylon-11 and nylon-12 by Fourier transform far-infrared spectroscopy. Different spectral features among the four species were interpreted as the characteristics of crystalline conformations of nylons. © 2012 IEEE.2012, International Conference on Infrared, Millimeter, and Terahertz Waves, IRMMW-THz, English
- The exact molecular chain orientation of poly(beta-hydroxybutyrate) (PHB) in ultrathin films was successfully probed using surface-sensitive, grazing incidence X-ray diffraction techniques. The crystal orientation of spin-coated PHB films was very sensitive to free surface and thermal annealing. In pristine films, the free surface easily exerted its influence on PHB crystallization and caused lamellar orientation with the b-axis perpendicular to the film surface. The effect of the buried interface increased with temperature. With the increase in thermal annealing temperature, the lamellar orientation changed from the b-axis being perpendicular to the film surface to the c-axis becoming perpendicular to the film surface. As film thickness increased, the temperature, at which the lamellae with the b-axes oriented normal to the film surface disappeared, increased. The thickness and temperature dependence of the crystallization behavior of PHB in an ultrathin film could be attributed to the competition between the effects of the free surface and the buried interface. (C) 2011 Elsevier Ltd. All rights reserved.ELSEVIER SCI LTD, Aug. 2011, POLYMER, 52(17) (17), 3865 - 3870, English[Refereed]
- Isothermal crystallization of poly(3-hydroxy-butyrate) was studied by terahertz time-domain spectroscopy. The temporal change of the ratio between the crystalline and amorphous structure was estimated by the integrated absorption intensity. The crystallization process was discussed by using Avrmi's equation.IEEE, 2011, 2011 36TH INTERNATIONAL CONFERENCE ON INFRARED, MILLIMETER, AND TERAHERTZ WAVES (IRMMW-THZ), English[Refereed]
- 2010, 分析化学討論会講演要旨集, 71st遠紫外減衰全反射分光法による液体アルカンとポリエチレンの電子状態研究
- 01 Jun. 2009, 高分子, 58(6) (6), 417 - 417, JapaneseYou Can Choose Both, Research and Child-Raising!
- 2009, 日本分析化学会年会講演要旨集, 58th近赤外分光法によるレシチン/水/イソオクタン系逆ミセルサイズと包含された水の状態の相関に関する研究
- 2009, 日本分析化学会年会講演要旨集, 58th近赤外分光法によるイオン性及び非イオン性界面活性剤逆ミセル中の水の状態比較
- 日本分析化学会, 05 Jun. 2007, ぶんせき, 0(390) (390), 270 - 275, JapaneseFailure toward Success in Analytical Techniques : Infrared and Raman Spectroscopy
- 2007, 分析化学討論会講演要旨集, 68th遠紫外分光法による食品用ラップフィルムの分別と,ポリマーフィルムの厚さ依存測定の研究
- 2007, 分析化学討論会講演要旨集, 68th水溶液中微量成分測定のための「ATR遠紫外分光装置」の開発
- Infrared (IR) and Rama n spectra were measured for ultra-high-molecular- weight poly(3-hydroxybutyrate) (UHMW-PHB) to investigate the crystalline structure and orientation. Comparison of the Raman spectra of a- and ß-structures of PHB with the results of quantum chemical calculations revealed that the bands at 966, 935, 908, and 858 cm assignable to the ß-structure.01 Dec. 2006, Polymer Preprints, Japan, 55, 3563
- 05 Sep. 2006, 高分子学会予稿集(CD-ROM), 55(2 Disk1) (2 Disk1), 2PF052, Japanese赤外・ラマン分光法と量子化学計算を用いたポリヒドロキシブタン酸の結晶構造と配向性に関する研究
- 京都 : 堀場製作所, May 2006, Readout : Horiba technical reports, (32) (32), 4 - 9, Japanese赤外分光法とX線回折法による生分解性高分子のC-H…O水素結合の研究--"弱い水素結合"が結晶構造安定化と熱的挙動に果たす役割—特集 第2回堀場雅夫賞
- 2006, 溶液化学シンポジウム講演要旨集, 29th二液相分離臨界点近傍においてC-H伸縮振動数が示すユニバーサリティ・クラス
- The crystalline structure and orientation of CH-O hydrogen bonding of Poly(hydroxybutyrate) have been explored by means of polarized infrared (IR) spectroscopy and quantam chemical calculation. It has been found that C=O and CH stretching bands show opposite behavior with polarization angle.01 Dec. 2005, Polymer Preprints, Japan, 54, 604
- Temperature-dependent x-ray diffraction and infrared (IR) spectra were measured for biodegradable poly(3-hydroxybutyrate) (PHB) and polyester, poly(3-hydroxybutyrate-co-3hydroxyhexanoate) P(HB-co-HHx) (HHx=2.5, 3.4, 10.5, and 12 mol %) to explore their crystal and lamella structure and the GH⋯O=C hydrogen bonding in them. It is very likely that the C-H⋯O=C hydrogen bonding stabilizes the chain holding in the lamella structure of PHB and P(HB-co-HHx) and affects the differences in the thermal behavior between PHB and P(HB-co-HHx).01 Dec. 2005, Polymer Preprints, Japan, 54, 3161 - 3162
- 05 Sep. 2005, 高分子学会予稿集(CD-ROM), 54(2 Disk1) (2 Disk1), 3E10, Japaneseポリヒドロキシブタン酸におけるCH‐‐‐O=C水素結合の役割
- 10 May 2005, 高分子学会予稿集(CD-ROM), 54(1 Disk1) (1 Disk1), 1C13, Japanese偏光赤外分光法と量子化学計算によるPoly(hydroxyalkanoate)中のCH‐‐‐O水素結合の研究
- 東京化学同人, May 2005, 現代化学, (410) (410), 24 - 31, JapaneseC-H…O水素結合--注目される"弱い相互作用"の役割
- The crystalline structure and thermal behavior of new types of bacterial copolyester, poly (3-hydroxybutyrate-<I>co</I>-3-hydroxyhexanoate) and polyhydroxybutyrate, PHB have been explored by means of wide-angle x-ray diffraction (WAXD) and infrared (IR) spectroscopy. It has been found from the temperature dependent variations of the WAXD pattern and IR spectra that C-H…O hydrogen bonding between C=O groups and CH<SUB>3</SUB> groups along the <I>a</I> axis and that the interactions are broken little by little from just above room temperature. The C-H…O hydrogen bonding between C=O groups and...The Crystallographic Society of Japan, 24 Dec. 2004, Nihon Kessho Gakkaishi, 46(6) (6), 426 - 432, Japanese
- 高分子刊行会, May 2004, 高分子加工, 53(5) (5), 202 - 213, Japanese生分解性ポリマーの構造と熱的挙動--X線回折と振動分光法による研究
- 化学工業社, Apr. 2001, 化学工業, 52(4) (4), 286 - 292, Japanese複雑なスペクトルをいかに解析するか(1)振動スペクトルを例として (特集/分光・分析研究と応用)
- AMER CHEMICAL SOC, Mar. 2000, ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY, 219, U502 - U502, EnglishIR, Raman, and near-IR studies on structure-properties relationship in high-density and low-density polyethylenes.Summary international conference
- Editor, Chapter 1, Chapter 4, Chapter 16, Wiley-VCH, Jan. 2022, Co-authored internationally, ISBN: 3527348336Spectroscopic Techniques for Polymer Characterization: Methods, Instrumentation, ApplicationsScholarly book
- Contributor, 第13章「高分子のテラヘルツおよび低波数Raman分光」佐藤春実, 化学同人, Dec. 2021, Japanese, ISBN: 9784759814026赤外線の化学利用 : 近赤外からテラヘルツまでScholarly book
- Contributor, 第3章4節「テラヘルツイメージング分光による高分子材料の劣化の可視化と分析」佐藤春実, 技術情報協会, Feb. 2017, Japanese, ISBN: 9784861046483高分子の残留応力対策Scholarly book
- Contributor, Chapter4 “Raman and tip-enhanced Raman scattering spectroscopy studies of polymer nanocomposites” Xinlei Yan, Harumi Sato and Yukihiro Ozaki, William Andrew, Feb. 2016, English, ISBN: 032340183XSpectroscopy of Polymer Nanocomposites (Micro and Nano Technologies)Scholarly book
- Contributor, 5章3節「高分子化学」, 講談社, Mar. 2015, Japanese, ISBN: 9784061569027近赤外分光法Scholarly book
- Contributor, vol.2 Chapter22 "Characterization of Polymer Blends by Infrared, Near-Infrared, and Raman Imaging", Harumi Sato, Miriam Unger, Dieter Fischer, Yukihiro Ozaki and Heinz W.Siesler, Wiley-VCH, Feb. 2015, English, ISBN: 3527331530Characterization of polymer blends : miscibility, morphology and interfacesScholarly book
- Contributor, 第2部9章「高分子の結晶構造と分子間相互作用」佐藤春実, 講談社, Feb. 2015, Japanese, ISBN: 9784061543867高分子赤外・ラマン分光法 = Infrared and Raman spectroscopy of polymersScholarly book
- Contributor, 第5章 物質の性質, 培風館, Jan. 2015, Japanese, ISBN: 9784563046200エッセンシャル化学Scholarly book
- Contributor, 第2章6節「赤外・ラマン分光法による高分子の表面解析」佐藤春実, シーエムシー出版, Nov. 2012, Japanese, ISBN: 9784781305950高分子の表面改質・解析の新展開Scholarly book
- Contributor, 第II部2章(3)「近赤外分光法」尾崎幸洋・佐藤春実, 講談社, Apr. 2010, Japanese, ISBN: 9784061543607高分子分析入門Scholarly book
- Contributor, Chapter 14 “Vibrational Sp2015ectroscopy Imaging in Polymer Research”, Harumi Sato, Yukihiro Ozaki, Jianhui Jiang, Ru-Qin Yu, Hideyuki Shinzawa, John Wiley & Sons, 2010, English, ISBN: 9780470382042Raman, infrared, and near-infrared chemical imagingScholarly book
- Contributor, 第9章「赤外・ラマン分光法による高分子の表面解析」佐藤春実・森田成昭, シーエムシー出版, Mar. 2009, Japanese, ISBN: 9784781301037高分子表面・界面分析法の新展開Scholarly book
- Contributor, 第1編「原理編」, 第2章 物理的検出法, 第1節 一般分光法(4頁 赤外・ラマン), エヌ・ティー・エス, Dec. 2004, Japanese, ISBN: 4860430670先端の分析法 : 理工学からナノ・バイオまでScholarly book
- 若手フロンティア研究会2024(神戸大学百年記念館), Dec. 2024, Japaneseラマン分光法によるP(3HB)およびP(3HB-co-4HB)の海洋分解性の評価Poster presentation
- 若手フロンティア研究会2024(神戸大学百年記念館), Dec. 2024, Japanese振動分光法によるポリブチレンアジペートの結晶多型とその海洋分解性の評価Poster presentation
- 若手フロンティア研究会2024(神戸大学百年記念館), Dec. 2024, EnglishStudy on Brill transition of polyamide 6 using Raman spectroscopy and quantum chemical calculationsPoster presentation
- 若手フロンティア研究会2024(神戸大学百年記念館), Dec. 2024, Japaneseラマン分光法と多変量解析を用いたポリプロピレンの紫外線劣化評価Poster presentation
- SciX 2024, Oct. 2024, EnglishLow-frequency Raman and far-infrared/terahertz spectroscopy studies of polymers[Invited]Invited oral presentation
- Symposium on Polymer Spectroscopy, Sep. 2024, EnglishMarine degradation of biodegradable polymers studied by 2D- and 3D-Raman imaging[Invited]Keynote oral presentation
- International Conference on Raman Spectroscopy, Aug. 2024, EnglishVisualization of Marine Degradation Process of Poly(ε-caprolactone) using Raman Spectroscopy[Invited]Invited oral presentation
- 第70回高分子研究発表会(神戸), Jul. 2024, Japanese振動分光法を用いた昇温及び延伸におけるポリブチレンアジペートの結晶構造に関する研究Poster presentation
- 第70回高分子研究発表会(神戸), Jul. 2024, EnglishStudy on Brill transition of polyamide 6 using low- and high-frequency Raman spectroscopyPoster presentation
- 第70回高分子研究発表会(神戸), Jul. 2024, Japanese2Dおよび3Dラマンマッピングによるポリヒドロキシブタン酸の海洋分解過程の可視化Poster presentation
- 第73回高分子年次大会, Jun. 2024, EnglishStudy on crystal structure and Brill transition of polyamide 6 using low-frequency vibrational spectroscopyPoster presentation
- 第73回高分子年次大会, Jun. 2024, Japaneseラマンマッピング法による生分解性ポリエステルの海洋分解過程の可視化Oral presentation
- 第73回高分子年次大会, Jun. 2024, Japaneseラマン分光法を用いたポリヒドロキシブタン酸の海洋分解過程の可視化Poster presentation
- 1st Symposium of "Asian Research Network for Terahertz Molecular Science, Mar. 2024, EnglishTHz and low-frequency Raman spectroscopies in Polymers[Invited]Invited oral presentation
- 1st Symposium of "Asian Research Network for Terahertz Molecular Science, Mar. 2024, EnglishAdvancements in DFT-Based Methods for Calculating Vibronic Properties of Molecules and Crystals, and Analyzing Terahertz Spectroscopy ResultsOral presentation
- 1st Symposium of "Asian Research Network for Terahertz Molecular Science, Mar. 2024, EnglishTHz Raman observation of semi-clathrate hydrates and salt hydratesOral presentation
- 1st Symposium of "Asian Research Network for Terahertz Molecular Science, Mar. 2024, EnglishA Comparative Study of Terahertz and Near-Infrared Spectroscopies for Accurate Classification of Gluten-Free and Gluten-Containing FloursOral presentation
- 1st Symposium of "Asian Research Network for Terahertz Molecular Science, Mar. 2024, EnglishTerahertz Spectroscopy for Identifying and Utilizing Indonesia's Natural ResourcesOral presentation
- 若手フロンティア研究会2023, Dec. 2023, Japaneseテラヘルツ時間領域分光法を用いた汎用ポリマーの劣化評価Poster presentation
- 若手フロンティア研究会2023, Dec. 2023, Japanese低波数領域の振動分光法によるP(LLA-co-CL)共重合体の高次構造の検討と海洋分解性の評価Poster presentation
- 若手フロンティア研究会2023, Dec. 2023, Japanese低波数領域の振動分光法と量子化学計算によるポリトリメチレンテレフタレートのメチレン基の数に起因する結晶構造への影響についてPoster presentation
- 2023年日本分光学会年次講演会, Oct. 2023, EnglishStudy on Brill transition and crystalline properties of polyamide using multiple spectroscopic techniquesPoster presentation
- 2023年日本分光学会年次講演会, Oct. 2023, Japaneseラマン分光法を用いたポリヒドロキシブタン酸の海洋分解過程の可視化Poster presentation
- 2023年日本分光学会年次講演会, Oct. 2023, Japaneseテラヘルツ領域の振動分光法を用いた PLA/PCL 共重合体とホモポリマーとの高次構造の比較Poster presentation
- 2023年日本分光学会年次講演会, Oct. 2023, Japaneseテラヘルツ分光法と量子化学計算による ポリトリメチレンテレフタレートの高次構造解析Poster presentation
- 第72回高分子討論会, Sep. 2023, Japanese低波数領域の振動分光法によるPCL-PLA共重合体の組成比変化に伴う高次構造の研究Poster presentation
- 第72回高分子討論会, Sep. 2023, Japanese低波数領域の振動分光法と量子化学計算によるポリトリメチレンテレフタレートの高次構造解析Poster presentation
- 第72回高分子討論会, Sep. 2023, English多様な分光学的手法を用いたポリアミドのブリル転移に関する研究Poster presentation
- 第72回高分子討論会, Sep. 2023, Japanese低波数領域の振動分光法を用いた海洋分解過程の生分解性ポリエステルフィルムの構造解析Oral presentation
- International Conference on Advanced Vibrational Spectroscopy (ICAVS12), Aug. 2023, EnglishVisualization of Intermolecular Hydrogen Bonding of Poly(ε-caprolactone) during Marine Degradation using Low-frequency Raman SpectroscopyOral presentation
- 第17回近畿支部夏季セミナー~ぶんせき秘帖 巻ノ壱拾七~, Aug. 2023, Japanese低波数領域の振動分光法と量子化学計算を用いたポリトリメチレンテレフタレートの高次構造解析Poster presentation
- 第17回近畿支部夏季セミナー~ぶんせき秘帖 巻ノ壱拾七~, Aug. 2023, Japaneseテラヘルツ領域の振動分光法を利用したポリ(ラクチド-co-カプロラクトン)(LCL)共重合体の高次構造の研究Poster presentation
- 第17回近畿支部夏季セミナー~ぶんせき秘帖 巻ノ壱拾七~, Aug. 2023, JapaneseTHz-TDSを用いた汎用プラスチックの分類と劣化評価Poster presentation
- 第17回近畿支部夏季セミナー~ぶんせき秘帖 巻ノ壱拾七~, Aug. 2023, EnglishStudy on Brill transiton of polyamide 6 utilizing various spectroscopic methodsPoster presentation
- 第69回高分子研究発表会(神戸), Jul. 2023, JapaneseTHz分光法による高分子素材種の識別Poster presentation
- 第69回高分子研究発表会(神戸), Jul. 2023, Japaneseポリ(ラクチド-co-カプロラクトン)共重合体のテラヘルツ領域における振動モードのホモポリマーとの比較Poster presentation
- 第69回高分子研究発表会(神戸), Jul. 2023, EnglishStudy of brill transition and crystalline properties of polyamide 6 using low-frequency raman spectroscopyOral presentation
- 第72回高分子学会年次大会, May 2023, Japanese低波数ラマン分光法を用いたポリカプロラクトンの海洋分解過程の研究Oral presentation
- 第72回高分子学会年次大会, May 2023, Japanese振動分光法を用いた高分子共重合体の高次構造の研究Poster presentation
- 膜工学春季講演会・膜工学サロン,サロンG「膜バイオプロセス」, Mar. 2023生分解性ポリエステルフ ィルムの海洋分解過程における分子間水素結合の可視化Public discourse
- CREST「分解と安定化」Webinar勉強会, Mar. 2023振動分光法を用いた高分子の構造・特性解析Public discourse
- 若手フロンティア研究会2022, Dec. 2022ラマン分光法を用いた共重合体ポリマーの分子間相互作用に関する研究Poster presentation
- 若手フロンティア研究会2022, Dec. 2022ラマン分光法を用いたPCLの海洋分解過程の観察Poster presentation
- 若手フロンティア研究会2022, Dec. 2022低波数領域の振動分光法を用いたポリブチレンサクシネートの分子間水素結合に関する研究Poster presentation
- 若手フロンティア研究会2022, Dec. 2022ポリトリメチレンテレフタレートの低波数領域の振動分光法を用いた高次構造解析Poster presentation
- 若手フロンティア 研究会2022, Dec. 2022振動分光法を用いた高分子共重合体の高次構造の研究Poster presentation
- ものづくり分析評価技術研究会 テラヘルツ分光編(初級者向け)第4回 「 テラヘルツ分光 法の測定と応用」, Dec. 2022高分子のテラヘルツ分光Public discourse
- 日本結晶学会年会, Nov. 2022ガラス状態におけるポリスチレン超薄膜の体積緩和の分子量・膜厚依存性Oral presentation
- 第1回光散乱透視学セミナー, Nov. 2022テラヘルツおよび低波数ラマン分光法を用いたプラスチッ クの海洋分解過程の観察Public discourse
- 第31 回日本赤外線学会研究発表会, Nov. 20223D プリンターを用いたテラヘルツ帯ロッドアンテナの作製と評価Poster presentation
- 第71回高分子討論会, Sep. 2022低波数領域の振動分光法及び量子化学計算によるポリブチレンサクシネートに関する研究Oral presentation
- 高分子研究発表会(神戸), Jul. 2022ポリトリメチレンテレフタレートの低波数領域における振動分光法による高次構造解析Poster presentation
- 高分子研究発表会(神戸), Jul. 2022テラヘルツ及び低波数ラマン分光法によるポリブチレンサクシネートの高次構造に関する研究Poster presentation
- 高分子研究発表会(神戸), Jul. 2022低波数領域を含む振動分光法を用いたPCLの海洋分解過程の観察Poster presentation
- 高分子研究発表会(神戸), Jul. 2022, EnglishStudy of PA6 performance under temperature variance, UV irradiation and seawater immersion using low- frequency Raman spectroscopyOral presentation
- 高分子研究発表会(神戸), Jul. 2022低波数ラマン分光法を用いたスチレンアクリロニトリル共重合体中の水素結合に関する研究Poster presentation
- オプトロニクス社「分光基礎セミナー 第3回 テラヘルツ分光法」, Jun. 2022THz-TDSのポリマー評価への応用Public discourse
- 第71回高分子学会年次大会, May 2022低波数ラマン及びテラヘルツ分光法によるポリブチレンサクシネートの熱挙動Poster presentation
- 第71回高分子学会年次大会, May 2022低波数領域の振動分光法によるポリトリメチレンテレフタレートの高次構造解析Poster presentation
- 第71回高分子学会年次大会, May 2022低波数ラマン分光法を用いたスチレンアクリロニトリル共重合体中の分子間相互作用に関する研究Poster presentation
- 第71回 高分子学会年次大会, May 2022ラマン分光法を用いたカラギーナンの分子間相互作用に関する研究Poster presentation
- 第71回高分子学会年次大会, May 2022, EnglishStudy of PA6 thermal properties and natural degradation using low-frequency spectroscopy methodOral presentation
- レーザー学会学術講演会 第42回年大会, Jan. 2022, Japaneseマイクロプラスチックによる細胞への影響と毒性の研究Oral presentation
- 若手フロンティア研究会2021, Dec. 2021, Japanese振動分光法を用いたPVA/PMMAブレンドの分子内・分子間相互作用に関する研究Poster presentation
- 若手フロンティア研究会2021, Dec. 2021, Japanese低波数領域を含むラマン分光法を用いたカラギーナンの分子間相互作用に関する研究Poster presentation
- 若手フロンティア研究会2021, Dec. 2021, Japaneseテラヘルツおよび低波数ラマン分光法によるポリブチレンサクシネートの分子間水素結合に関する研究Poster presentation
- 若手フロンティア研究会2021, Dec. 2021, Japanese温度変化ラマンスペクトルによる共重合体ポリマーの分子間相互作用に関する研究Poster presentation
- 若手フロンティア研究会2021, Dec. 2021, Japanese低波数領域の振動分光法を用いたポリヒドロキシ酪酸/ポリ乳酸ブレンドの相分離挙動の可視化Poster presentation
- 2021 International Chemical Congress od Pacific Basin Societies (Pacifichem 2021), Dec. 2021, EnglishIntermolecular interaction of PVA/PMMA blend studied by IR and Raman spectroscopyPoster presentation
- 2021 International Chemical Congress od Pacific Basin Societies (Pacifichem 2021), Dec. 2021, EnglishStudy on the higher-order structure and hydrogen bonding of biodegradable polymer by low-frequency vibrational spectroscopyPoster presentation
- 2021 International Chemical Congress od Pacific Basin Societies (Pacifichem 2021), Dec. 2021, EnglishStudy of electronic transitions of polymers by far-ultraviolet spectroscopyOral presentation
- 2021 International Chemical Congress od Pacific Basin Societies (Pacifichem 2021), Dec. 2021, EnglishHydrogen bonding and higher order structure of polymers by low-frequency vibrational spectroscopyOral presentation
- 第30回日本赤外線学会研究発表会, Oct. 2021, Japaneseテラヘルツ分光法および低波数ラマン分光法を用いた高分子結晶構造中の分子間水素結合の研究[Invited]Invited oral presentation
- 第70回高分子討論会, Sep. 2021低波数領域の振動分光法によるポリブチレンサクシネートの分子間水素結合に関する研究Poster presentation
- 第70回高分子討論会, Sep. 2021振動分光法を用いたカラギーナンの分子間相互作用に関する研究Poster presentation
- 日本調理科学会2021年度大会, Sep. 2021, Japanese炊飯における浸漬温度が米粒表面部のでんぷんに及ぼす影響Oral presentation
- 11th International Conference on Advanced Vibrational Spectroscopy (ICAVS-11), Aug. 2021Study on intermolecular interaction of polymers using vibrational spectroscopy[Invited]Keynote oral presentation
- The Eleventh International Symposium on Two-Dimensional Correlation Spectroscopy (2DCOS-11), Aug. 2021Raman spectroscopic evidence of free-OH in cold water using derivative double 2DCOS and local-MCROral presentation
- 第67回高分子研究発表会(神戸), Jul. 2021PVAのブレンド化による分子内・分子間水素結合に関する研究Poster presentation
- 第67回高分子研究発表会(神戸), Jul. 2021振動分光法及び量子化学計算を用いたポリブチレンサクシネートの分子間水素結合に関する研究Poster presentation
- 第67回高分子研究発表会(神戸), Jul. 2021ラマン分光法によるスチレンアクリロニトリル共重合体中の分子間相互作用に関する研究Poster presentation
- 第70回高分子学会年次大会(オンライン開催), May 2021, Japanese振動分光法を用いた PVA/PMMA ブレンドの分子間相互作 用に関する研究Poster presentation
- 第70回高分子学会年次大会(オンライン開催), May 2021, Japanese赤外分光法及び量子化学計算によるポリブチレンサクシネ ートの分子間水素結合の検討Poster presentation
- 第70回高分子学会年次大会(オンライン開催), May 2021, Japanese低波数ラマン分光法を用いたスチレンアクリロニトリル共重 合体の熱挙動に関する研究Poster presentation
- 医用分光学研究会 第18回年会(オンライン開催; 島根大担当), Nov. 2020, Japanese赤外、ラマン、近赤外、低波数分光、遠紫外分光による水の研究Keynote oral presentation
- 第69回 高分子討論会(オンライン開催;岩手大学担当), Sep. 2020, Japaneseテラヘルツおよび低波数ラマン分光法による PGAPLA 共重合体の組成比変化に伴う高次構造の研究Oral presentation
- 第69回 高分子討論会(オンライン開催;岩手大学担当), Sep. 2020, Japaneseラマン及び赤外スペクトルに現れる水と高吸水性樹脂中の水の振動モードの比較Oral presentation
- 第69回 高分子討論会(オンライン開催;岩手大学担当), Sep. 2020, Japanese振動分光法を用いたεポリ(L)リジンの吸水による高次構造の研究Oral presentation
- 第66回高分子研究発表会, Jul. 2020, Japanese低波数領域の振動分光法を用いたεポリ(L)リジンの高次構造の研究
- 第66回高分子研究発表会, Jul. 2020, Japaneseポリ(グリコリド-ラクチド)共重合体の低波数領域における振動モードの組成比依存性
- 第66回高分子研究発表会, Jul. 2020, Japanese高吸水性樹脂中の水の振動モードの低波数領域と高波数領域の比較
- 第66回高分子研究発表会, Jul. 2020, Japanese生分解性ポリマーブレンドのテラヘルツイメージングによるモルフォロジー観察
- 第69回高分子学会年次大会, May 2020, Japanese低波数ラマン分光法と赤外分光法によるアクリル酸系高吸水性樹脂中の水の構造Poster presentation
- 第69回高分子学会年次大会, May 2020, JapaneseTHz イメージングによるポリヒドロキシブタン酸/ポリ乳酸ブ レンドの相分離Poster presentation
- The 8th International Workshop on Far-Infrared Technologies (IW-FIRT 2021) (Online Conference), Mar. 2021, EnglishIntermolecular hydrogen boinding of polymer by terahertz and low-frequency Raman spectroscopy[Invited]Invited oral presentation
- 若手フロンティア研究会2019(神戸大学), Dec. 2019, JapaneseTHz分光法による高分子共重合体の高次構造の研究Poster presentation
- 若手フロンティア研究会2019(神戸大学), Dec. 2019, Japaneseテラヘルツ分光法を用いたポリジオキサノンの結晶相転移に関する研究Poster presentation
- 若手フロンティア研究会2019(神戸大学), Dec. 2019, Japaneseテラヘルツ分光法によるエンジニアリングポリエステルのメチレン鎖の長さによる結晶化の研究Poster presentation
- 若手フロンティア研究会2019(神戸大学), Dec. 2019, Japanese低波数ラマン分光法を用いた高吸水性樹脂の水との相互作用Poster presentation
- 若手フロンティア研究会2019(神戸大学), Dec. 2019, Japanese第四級オニウム塩ハイドレートにおける低波数ラマン分光分析Poster presentation
- 第28回ポリマー材料フォーラム, Nov. 2019, Japaneseテラヘルツ波を利用したPETとPBTの分子間相互作用の直接観察Poster presentation
- 第10回イオン液体討論会, Nov. 2019, Japaneseトリブチルアルキルホスホニウムカチオンを内包したセミクラスレートハイドレートの物理化学特性Poster presentation
- 第10回イオン液体討論会, Nov. 2019, Japanese低波数Raman分光法によるTBA/TBPハイドレートにおけるゲスト分子相互作用が与える影響の評価Oral presentation
- 学振182委員会 第3期第4回研究会, Oct. 2019, Japaneseテラヘルツ分光を利用した高分子材料の物性評価[Invited]Invited oral presentation
- 第68回高分子学会討論会, Sep. 2019, Japaneseテラヘルツ分光法を用いたポリジオキサノンの分子間相互作用と結晶化挙動の研究Oral presentation
- 第68回高分子学会討論会, Sep. 2019, Japaneseテラヘルツ分光法、低波数ラマン分光法、量子化学計算によるPETおよびPBTの高次構造解析Oral presentation
- 第68回高分子学会討論会, Sep. 2019, Japanese赤外分光法及びテラヘルツラマン分光法によるεポリ(L)リ ジンの高次構造の研究Poster presentation
- 第68回高分子学会討論会, Sep. 2019, Japaneseテラヘルツおよび低波数ラマン分光法を用いたポリ(グリコ リド-co-ラクチド)共重合体の高次構造の研究Poster presentation
- The 7th International Conference on DV-Xα Method (ICDM), Sep. 2019, EnglishStudy on The Higher-Order Structure and Hydrogen Bonding of Biodegradable Polymer by Low-Frequency Vibrational Spectroscopy[Invited]Invited oral presentation
- The 7th International Conference on DV-Xα Method (ICDM), Sep. 2019, EnglishWeek Hydrogen Bonding of Polymers Studied by Terahertz and Low-frequency Raman Spectroscopy[Invited]Invited oral presentation
- The The 10th International Symposium on Two-dimensional Correlation Spectroscopy (2DCOS-10), Aug. 2019, EnglishThe study of crystalline phase transition in PHB/PVPh blends using Far-IR, Raman, WAXD and 2D correlation analysis[Invited]Invited oral presentation
- The The 10th International Symposium on Two-dimensional Correlation Spectroscopy (2DCOS-10), Aug. 2019, EnglishLow-Frequency Vibrational Modes of Nylon 6 Studied by Using Far-Infrared, Raman and 2D Correlation Spectroscopies[Invited]Invited oral presentation
- 第28回日本エネルギー学会, Aug. 2019, JapaneseTBA/TBP bromide ハイドレートのゲスト分子相互作用の差異Oral presentation
- 第13回近畿支部夏季セミナー ~ぶんせき秘帖 巻ノ拾参~, Aug. 2019, Japanese低波数ラマン分光法による高吸水性ポリマーの水との相互作用Poster presentation
- 第13回近畿支部夏季セミナー ~ぶんせき秘帖 巻ノ拾参~, Aug. 2019, Japanese振動分光法による分子量の異なるポリヒドロキシブタン酸共重合体の結晶化挙動Poster presentation
- 第65回高分子研究発表会(神戸), Jul. 2019, Japaneseテラヘルツ領域におけるεポリ(L)リジンの高次構造に関する研究Poster presentation
- 第65回高分子研究発表会(神戸), Jul. 2019, EnglishThe investigation of Higher-Order Structure on Polymer Blend Poly(3-hydroxybutyrate)/Poly(4-vinylphenol)by Terahertz and Low-Frequency Raman SpectroscopyOral presentation
- 第65回高分子研究発表会(神戸), Jul. 2019, Japanese振動分光法によるポリヒドロキシブタン酸共重合体の結晶化速度の分子量依存性に関する研究Poster presentation
- 10th International Conference on Advanced Vibrational Spectroscopy (ICAVS 10), Jul. 2019, EnglishWeek Hydrogen Bonding of Biodegradable Polyester Studied by Terahertz Spectroscopy[Invited]Invited oral presentation
- Jul. 2019, EnglishA Study on Correlation between Intermolecular Interaction and UV Degradation of Polydioxanone by Terahertz SpectroscopyPoster presentation
- 10th International Conference on Advanced Vibrational Spectroscopy (ICAVS 10), Jul. 2019, EnglishStudy of higher order structure of poly(glycolide-co-lactide) by THz and low frequency Raman spectroscopyPoster presentation
- 10th International Conference on Advanced Vibrational Spectroscopy (ICAVS 10), Jul. 2019, EnglishStudey on hydration of super absorbent polymer by lowfrequency Raman spectroscopyPoster presentation
- 10th International Conference on Advanced Vibrational Spectroscopy (ICAVS 10), Jul. 2019, EnglishA study of hydrogen bondings of PET and PBT by terahertz spectroscopy and quantum chemical calculationsPoster presentation
- 第68回高分子学会年次大会, May 2019, Japanese, 大阪府立国際会議場, Domestic conference低波数ラマン分光法を用いた高吸水性樹脂の水和に関する研究Poster presentation
- 第68回高分子学会年次大会, May 2019, Japanese, 大阪府立国際会議場, Domestic conference振動分光法によるポリヒドロキシブタン酸共重合体の分子量依存性に関する研究Poster presentation
- 第68回高分子学会年次大会, May 2019, Japanese, 大阪府立国際会議場, Domestic conferenceポリ(グリコリド-co-ラクチド)共重合体のテラヘルツ分光法による高次構造の研究Poster presentation
- 第68回高分子学会年次大会, May 2019, Japanese, 大阪府立国際会議場, Domestic conferenceテラヘルツ分光法および低波数ラマン分光法によるポリエチレンテレフタレート及びポリブチレンテレフタレートの分子間相互作用と高次構造の研究Poster presentation
- 第68回高分子学会年次大会, May 2019, Japanese, 大阪府立国際会議場, Domestic conferenceテラヘルツ及びテラヘルツラマン分光法を用いたεポリ(L)リジンの高次構造の研究Poster presentation
- 第68回高分子学会年次大会, May 2019, English, 大阪府立国際会議場, Domestic conferenceThe investigation of Higher-Order Structure on Polymer Blend Poly(3-hydroxybutyrate)/Poly(4-vinylphenol) by Terahertz and Low-Frequency Raman SpectroscopyOral presentation
- レーザー学会 第39回年次大会, Jan. 2019, Japanese, 東海大学, Domestic conferenceテラヘルツ光源による高分子モルフォロジー観察[Invited]Invited oral presentation
- テラヘルツ科学の最先端Ⅴ, Dec. 2018, Japanese, Domestic conference低波数ラマンを用いた高吸水性樹脂の水和に関する研究Poster presentation
- テラヘルツ科学の最先端Ⅴ, Dec. 2018, Japanese, 千葉大学 けやき会館, Domestic conferenceポリ(グリコリド-co-ラクチド)共重合体のTHz分光法による高次構造の研究Poster presentation
- テラヘルツ科学の最先端Ⅴ, Dec. 2018, Japanese, 千葉大学 けやき会館, Domestic conferenceテラヘルツ分光法および低波数ラマン分光法を用いた結晶性エンジニアリングプラスチックの相互作用の研究Poster presentation
- IEEE MTT-S Kansai Chapterテクニカルワークショップ, Dec. 2018, Japanese, 京都工芸繊維大学, Domestic conferenceテラヘルツ分光の高分子材料への応用[Invited]Invited oral presentation
- The 3rd Aquaphotomics International Symposium, Dec. 2018, English, 淡路夢舞台, International conferenceStudy of Tetrabutylammonium Bromide Hydrate by Two spectroscopies in THz regionPoster presentation
- The 3rd Aquaphotomics International Symposium, Dec. 2018, English, 淡路夢舞台, International conferencePolymer structure in water studied by THz-Raman spectroscopy[Invited]Invited oral presentation
- The 3rd Aquaphotomics International Symposium, Dec. 2018, English, 淡路夢舞台, International conferenceMolecular dependence of collagen model peptide stuidied by low frequency Raman spectroscopyPoster presentation
- テラヘルツ科学の最先端Ⅴ, Dec. 2018, Japanese, 千葉大学 けやき会館, Domestic conferenceHydrogen-Bonding Interactions of Poly(3-hydroxybutyrate) / Poly(4-vinylphenol) Studied by Low Frequency-Raman SpectroscopyPoster presentation
- International Conference on Education and Social Science Research (ICESRE), Oct. 2018, English, Harris Hotel Semarang, Indonesia, International conferenceStructure and Physical Properties of Polymers Studied by SpectroscopyKeynote oral presentation
- International Conference on Community Service Programme 2018 (ICCSP), Oct. 2018, English, Harris Hotel Semarang, Indonesia,, International conferenceInternational Collaboration and University-High School CollaborationKeynote oral presentation
- 第67回高分子討論会, Sep. 2018, Japanese, 北海道大学, Domestic conference赤外分光法及び低波数ラマン分光法におけるコラーゲンモデル化合物の分子量依存性Poster presentation
- 第67回高分子討論会, Sep. 2018, Japanese, 北海道大学, Domestic conferenceテラヘルツ分光法による高分子の分子間相互作用の観測と物性評価への応用Poster presentation
- 第67回高分子討論会, Sep. 2018, Japanese, 北海道大学, Domestic conferenceテラヘルツ分光法によるポリブチレンテレフタレートの高次構造と結晶構造形成過程の研究Poster presentation
- 第67回高分子討論会, Sep. 2018, Japanese, 北海道大学, Domestic conferenceテラヘルツ分光法によるポリジオキサノンの結晶構造における相互作用の解明Poster presentation
- 第67回高分子討論会, Sep. 2018, English, 北海道大学, Domestic conferenceA Study of Hydrogen Bonding of Polyethylere Glycol / Chitosan Blends in the Low-frequency RegionPoster presentation
- the 26th International Conference on Raman Spectroscopy, Aug. 2018, English, Jeju Island, Korea, International conferenceThe Study of Intermolecular Interaction in Polymer Blend of Polyethylene Glycol and Cellulose Acetate Butyrate by Low-Frequency Raman SpectroscopyPoster presentation
- he 26th International Conference on Raman Spectroscopy, Aug. 2018, English, Jeju Island, Korea, International conferenceStudy on Intermolecular Interaction of Polydioxanone by Terahertz and low frequency Raman spectroscopyPoster presentation
- the 26th International Conference on Raman Spectroscopy, Aug. 2018, English, Jeju Island, Korea, International conferenceStudy of higher order structure of poly (ethylene terephthalate) and poly (butylene terephthalate) by low frequency Raman and terahertz spectoscopyPoster presentation
- the 26th International Conference on Raman Spectroscopy, Aug. 2018, English, Jeju Island, Korea, International conferenceStress-induced crystal transition of poly(butylenesuccinate) studied by terahertz and low-frequency Raman spectroscopy[Invited]Invited oral presentation
- the 26th International Conference on Raman Spectroscopy, Aug. 2018, English, Jeju Island, Korea, International conferenceObservation of THz-Raman Spectrum in Tetrabutylammonium Bromide HydratePoster presentation
- the 26th International Conference on Raman Spectroscopy, Aug. 2018, English, Jeju Island, Korea, International conferenceMolecular dependence of several collagen model peptides stuidied by low frequency Raman spectroscopyPoster presentation
- 高分子研究発表会, Jul. 2018, Japanese, 兵庫県民会館, Domestic conference赤外およびテラヘルツ分光法によるポリジオキサノンの分子間相互作用に関する研究Poster presentation
- 高分子研究発表会, Jul. 2018, English, 兵庫県民会館, Domestic conference振動分光法によるポリブチレンテレフタレートの分子間・分子内相互作用の研究Poster presentation
- 高分子研究発表会, Jul. 2018, Japanese, 兵庫県民会館, Domestic conference高感度反射赤外分光法を用いたポリメタクリル酸メチルとポリ4-ビニルフェノール超薄膜の相分離挙動と分子量依存性Poster presentation
- 高分子研究発表会, Jul. 2018, English, 兵庫県民会館, Domestic conferenceIntermolecular Interaction of Polyethylene Glycol / Cellulose Acetate Butyrate Blends by Terahertz SpectroscopyPoster presentation
- ICAMS, Jun. 2018, English, Kwansei Gakuin Kaikan, Nishinomiya, International conferenceThree different kinds of weak C-H…O=C inter- and intramolecular interactions in poly(ε-caprolactone) studied by terahertz spectroscopy, infrared spectroscopy and quantum chemical calculationsPoster presentation
- ICAMS, Jun. 2018, English, Kwansei Gakuin Kaikan, Nishinomiya, International conferenceObservation of THz- Raman Spectrum in Tetrabutylammonium Bromide HydratePoster presentation
- ICAMS, Jun. 2018, English, Kwansei Gakuin Kaikan, Nishinomiya, International conferenceMolecular weight dependence of phase separation of poly(methyl methacrylate)/poly(4-vinyl phenol) ultra-thin film studied by infrared reflection absorption spectroscopyPoster presentation
- ICAMS, Jun. 2018, English, Kwansei Gakuin Kaikan, Nishinomiya, International conferenceIntermolecular interaction of polydioxanone studied by terahertz spectroscopyPoster presentation
- ICAMS, Jun. 2018, English, Kwansei Gakuin Kaikan, Nishinomiya, International conferenceInter- and intra-molecular interaction of PET and PBT studied by terahertz spectroscopy,Poster presentation
- ICAMS, Jun. 2018, English, Kwansei Gakuin Kaikan, Nishinomiya, International conferenceHydration Study of Polyethylene Glycol Based Polymer Blend by Low-Frequency Raman SpectroscopyPoster presentation
- 高分子年次大会, May 2018, English, 名古屋国際会議場, Domestic conference外及びテラヘルツ分光法によるポリジオキサノンの結晶構造と分子間相互作用に関する研究Poster presentation
- 高分子年次大会, May 2018, Japanese, 名古屋国際会議場, Domestic conferenceラヘルツおよび赤外分光法によるポリブチレンテレフタレートの高次構造の研究Keynote oral presentation
- 高分子年次大会, May 2018, English, 名古屋国際会議場, Domestic conferenceHigher-Order Structure of Polyethylene Glycol and Its Blends Studied by Terahertz SpectroscopyOral presentation
- 第4回 関西接着ワークショップ「今後の発展が期待される解析技術」, Jan. 2018, Japanese, 大阪市立大学梅田サテライト 文化交流センター, Domestic conferenceテラヘルツ分光を利用した高分子の高次構造[Invited]Nominated symposium
- テラヘルツ科学の最先端Ⅳ, Dec. 2017, Japanese, KKRホテル熱海, Domestic conference低波数領域におけるポリブチレンサクシネート(PBS)の高次構造の研究Poster presentation
- テラヘルツ科学の最先端Ⅳ, Dec. 2017, Japanese, KKRホテル熱海, Domestic conferenceポリジオキサノン(PDS)のテラヘルツ分光法による分子間相互作用に関する研究Poster presentation
- テラヘルツ科学の最先端Ⅳ, Dec. 2017, Japanese, KKRホテル熱海, Domestic conferenceポリエチレンテレフタレート及びポリブチレンテレフタレートのTHz分光法による高次構造の研究Poster presentation
- テラヘルツ科学の最先端Ⅳ, Dec. 2017, English, KKRホテル熱海, Domestic conferenceHigher Ordered Structure of Chitosan Polyethylere Glycol Blends Studied by Terahertz SpectroscopyPoster presentation
- 第63回高分子研究発表会, Jul. 2017, Japanese, 兵庫県民会館, Domestic conference低波数ラマン及びテラヘルツ分光法によるコラーゲン及びコラーゲンモデル化合物の構造変化Poster presentation
- 第45回東北地区高分子若手研究会夏季ゼミナール, Jul. 2017, Japanese, 仙台市秋保温泉「岩沼屋」, Domestic conference高分子分光法による高分子の高次構造の研究[Invited]Invited oral presentation
- 第63回高分子研究発表会, Jul. 2017, Japanese, 兵庫県民会館, Domestic conferenceテラヘルツ分光法によるポリカプロラクトンの紫外線劣化と高次構造の相関Poster presentation
- 第63回高分子研究発表会, Jul. 2017, Japanese, 兵庫県民会館, Domestic conferenceテラヘルツ分光法によるステレオコンプレックス型ポリ乳酸の紫外線劣化過程に関する研究Poster presentation
- ICAVS2017, Jun. 2017, English, Victoria Conference Centre, International conferenceThermal Denaturation and structual changes of collagen model peptide studied by low frequency Raman and THz spectroscopyPoster presentation
- ICAVS2017, Jun. 2017, English, Victoria Conference Centre, International conferenceLow-Frequency Vibrational Modes of Crystalline Polyesters and Interchain Interaction Studied by Using DFT CalculationPoster presentation
- ICAVS2017, Jun. 2017, English, Victoria Conference Centre, International conferenceIntermolecular Interaction and Higher-Order Structure of Biodegradable Polyester Studied by Terahertz Spectroscopy[Invited]Invited oral presentation
- 第66回高分子年次大会, May 2017, Japanese, 幕張メッセ, Domestic conference低波数ラマン及びテラヘルツ分光法によるコラーゲン及びコラーゲンモデル化合物の構造変化Poster presentation
- 第66回高分子年次大会, May 2017, Japanese, 幕張メッセ, Domestic conferenceラマン・テラヘルツ分光法を用いたステレオコンプレックス型ポリ乳酸の紫外線劣化評価Poster presentation
- 第66回高分子年次大会, May 2017, Japanese, 幕張メッセ, Domestic conferenceテラヘルツ分光法を用いた太陽光パネル封止材の紫外線劣化評価Poster presentation
- 第66回高分子学会年次大会, May 2017, Japanese, 幕張メッセ, Domestic conferenceテラヘルツ時間領域分光法による延伸ポリ乳酸薄膜の光学異方性に関する研究Oral presentation
- 第64回応用物理学会春季学術講演会, Mar. 2017, Japanese, パシフィコ横浜, Domestic conference延伸ポリ乳酸薄膜を用いたテラヘルツ1/4波長板の作製Oral presentation
- Molecular Photoscience Research Center International Symposium, Mar. 2017, English, 神戸大学 瀧川記念会館, Domestic conferenceHigher-Order Structure of Biodegradable Polyesters Studied byTerahertz Spectroscopy[Invited]Invited oral presentation
- Japan-Taiwan Medical Spectroscopy International Symposium, Dec. 2016, English, Awaji Yumebutai International Confernce Center, International conferenceThermal denaturation of Collagen studied by ATR-IR, low frequency Raman and THz spectroscopyPoster presentation
- Japan-Taiwan Medical Spectroscopy International Symposium, Dec. 2016, English, Awaji Yumebutai International Confernce Center, International conferenceThermal and Ultraviolet Degradation of Poly(ethylene-co-vinyl acetate) Studied by Vibrational SpectroscopyPoster presentation
- Japan-Taiwan Medical Spectroscopy International Symposium, Dec. 2016, English, Awaji Yumebutai International Confernce Center, International conferenceThe change of higer-order structure and molecular weight dependence of poly(ethylene glycol) studied by low-frequency Raman spectroscopyPoster presentation
- Japan-Taiwan Medical Spectroscopy International Symposium, Dec. 2016, English, Awaji Yumebutai International Confernce Center, International conferenceTemperature- and Ultraviolet Irradiation -Induced Structural Changes of Poly(L-lactide)/Poly(D-lactide) Stereocomplex Studied by Raman and Terahertz SpectroscopiesPoster presentation
- Japan-Taiwan Medical Spectroscopy International Symposium, Dec. 2016, English, Awaji Yumebutai International Confernce Center, International conferenceStretch-induced crystalline phase transition of poly(butylene succinate) studied by polarized terahertz spectroscopyPoster presentation
- Japan-Taiwan Medical Spectroscopy International Symposium, Dec. 2016, English, Awaji Yumebutai International Confernce Center, International conferencePhase separation of poly(methyl methacrylate)/poly(4-vinyl phenol) ultra-thin film studied by infrared reflection adsorption spectroscopyPoster presentation
- Japan-Taiwan Medical Spectroscopy International Symposium, Dec. 2016, English, Awaji Yumebutai International Confernce Center, International conferenceMolecular Weight Dependence of the Formation of Weak Hydrogen Bonding in Poly(3-hydroxybutyrate)Poster presentation
- Japan-Taiwan Medical Spectroscopy International Symposium, Dec. 2016, English, Awaji Yumebutai International Confernce Center, International conferenceHigher-Order Structure of the Biodegradable Polymer Studied by Terahertz Spectroscopy[Invited]Invited oral presentation
- Japan-Taiwan Medical Spectroscopy International Symposium, Dec. 2016, English, Awaji Yumebutai International Confernce Center, International conferenceEvaluation of physical properties of poly(ε-caprolactone)studied by terahertz spectroscopyPoster presentation
- Japan-Taiwan Medical Spectroscopy International Symposium, Dec. 2016, English, Awaji Yumebutai International Confernce Center, International conferenceEffect of Additives on the Crystallization Behavior of Poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) Studied by Infrared SpectroscopyPoster presentation
- Japan-Taiwan Medical Spectroscopy International Symposium, Dec. 2016, English, Awaji Yumebutai International Confernce Center, International conferenceDepth direction analysisof polymer materialsby low-frequency RamanPoster presentation
- テラヘルツ科学の最先端Ⅲ, Nov. 2016, Japanese, 三国観光ホテル, Domestic conference低波数ラマンを用いたポリエチレングリコールの高次構造の変化と分子量依存性Poster presentation
- テラヘルツ科学の最先端Ⅲ, Nov. 2016, Japanese, 三国観光ホテル, Domestic conference延伸ポリ乳酸薄膜試料の作製とテラヘルツ偏光光学素⼦への応⽤Poster presentation
- テラヘルツ科学の最先端Ⅲ, Nov. 2016, Japanese, 三国観光ホテル, Domestic conferenceラマン・テラヘルツ分光法を⽤いたステレオコンプレックス型ポリ乳酸の構造変化に関する研究Poster presentation
- テラヘルツ科学の最先端Ⅲ, Nov. 2016, English, 三国観光ホテル, Domestic conferenceテラヘルツ分光法を用いたポリグリコール酸の結晶構造形成過程Poster presentation
- テラヘルツ科学の最先端Ⅲ, Nov. 2016, Japanese, 三国観光ホテル, Domestic conferenceテラヘルツ分光法によるポリカプロラクトンの紫外線劣化評価Poster presentation
- テラヘルツ科学の最先端Ⅲ, Nov. 2016, Japanese, 三国観光ホテル, Domestic conferenceTHz領域におけるポリブチレンサクシネートの延伸誘起結晶相転移Poster presentation
- 応用物理学会春季学術講演会, Sep. 2016, Japanese, 朱鷺メッセ:新潟コンベンションセンター, Domestic conference高複屈折性を有する延伸ポリ乳酸膜の作製Oral presentation
- 日本分析化学会第65年会, Sep. 2016, Japanese, 北海道大学, Domestic conferenceラマン・テラヘルツ分光法によるポリ乳酸及びステレオコンプレックス型ポリ乳酸の紫外線劣化と分子量依存性の研究Oral presentation
- 第65回高分子討論会, Sep. 2016, Japanese, 神奈川大学 横浜キャンパス, Domestic conferenceテラヘルツ分光法を用いた太陽光パネル封止材ポリエチレン-ポリ酢酸ビニル共重合体の劣化評価Poster presentation
- 日本物理学会, Sep. 2016, Japanese, 金沢大学, Domestic conferenceテラヘルツ分光法による高分子ポリ乳酸の光学異方性の研究Poster presentation
- 第65回高分子討論会, Sep. 2016, Japanese, 神奈川大学 横浜キャンパス, Domestic conferenceテラヘルツ分光法によるポリ(ε-カプロラックトン)の結晶構造における相互作用の解明Oral presentation
- ESOPS20, Sep. 2016, English, Dresden, International conferenceTHz and low-frequency Raman Spectroscopy of polymers[Invited]Invited oral presentation
- ESOPS20, Sep. 2016, English, Dresden, International conferenceStretch-induced crystalline phase transition of poly(butylene succinate) by Terahertz spectroscopyPoster presentation
- ESOPS20, Sep. 2016, English, Dresden, International conferenceEffect of additives on the crystallization behavior of poly(hydroxybutyrate-co-hydroxyhexanoate)Poster presentation
- ESOPS20, Sep. 2016, English, Dresden, International conferenceCharacterization of poly (ε-caprolactone)by using terahertz imagingPoster presentation
- IRMMW2016, Sep. 2016, English, Copenhagen, Denmark -Bella Centar, International conferenceBirefringent properties of poly-lactic acid at terahertz rangePoster presentation
- 第62回高分子研究発表会, Jul. 2016, Japanese, 兵庫県民会館, Domestic conferenceポリヒドロキシブタン酸共重合体の核剤添加による結晶化挙動Poster presentation
- 第62回高分子研究発表会, Jul. 2016, Japanese, 兵庫県民会館, Domestic conferenceテラヘルツ分光法を用いたポリブチレンサクシネートの結晶相転移Poster presentation
- 第62回高分子研究発表会, Jul. 2016, Japanese, 兵庫県民会館, Domestic conferenceテラヘルツイメージングによるポリカプロラクトン(PCL)の物性評価Poster presentation
- 日本分光学会年次講演会, May 2016, Japanese, 大阪大学 豊中キャンパス 基礎工学部 Σホール, Domestic conference量子力学計算によるポリグリコール酸の低波数振動の帰属Oral presentation
- 第65回高分子学会年次大会, May 2016, Japanese, 神戸国際会議場, International conference振動分光法を用いたポリブチレンサクシネートの延伸による結晶相転移の研究Poster presentation
- 第65回高分子学会年次大会, May 2016, Japanese, 神戸国際会議場, Domestic conference振動分光法および小角/広角X線散乱法による低分子量ポリヒドロキシブタン酸の結晶構造形成過程の研究Poster presentation
- 第65回高分子学会年次大会, May 2016, Japanese, 神戸国際会議場, Domestic conference高感度反射赤外分光法を用いた超薄膜状態におけるポリメタクリル酸メチルとポリ4-ビニルフェノールの相分離Poster presentation
- 第65回高分子学会年次大会, May 2016, Japanese, 神戸国際会議場, Domestic conferenceラマン・テラヘルツ分光を用いたポリ乳酸およびステレオコンプレックス型ポリ乳酸の分子間相互作用と結晶構造形成過程の研究Poster presentation
- 第65回高分子学会年次大会, May 2016, Japanese, 神戸国際会議場, Domestic conferenceポリヒドロキシブタン酸共重合体の結晶化挙動に及ぼす添加剤の影響Poster presentation
- 第65回高分子学会年次大会, May 2016, Japanese, 神戸国際会議場, Domestic conferenceテラヘルツ分光法を用いたポリ(ε-カプロラクトン)の結晶構造と熱挙動Poster presentation
- テラヘルツテクノロジーフォーラム第14回講演会, May 2016, Japanese, 大阪大学 医学・工学研究科 東京ブランチ, Domestic conferenceテラヘルツ分光法による高分子材料の劣化評価[Invited]Invited oral presentation
- 第65回高分子学会年次大会, May 2016, Japanese, 神戸国際会議場, Domestic conferenceテラヘルツイメージングによるポリカプロラクトン(PCL)の物性評価Poster presentation
- 第65回高分子学会年次大会, May 2016, English, 神戸国際会議場, Domestic conferenceThe evolution of intermediate and highly-ordered crystalline states under spatial confinement in poly(3-hydroxybutyrate) ultrathin filmsOral presentation
- Pacifichem2015, Dec. 2015, English, Hawaii Convention Center, International conferenceLow-frequency vibrational modes and intermolecular interaction of Nylon 6 studied by Raman, far-IR, and Terahertz Spectroscopies with Quantum Chemical CalculationOral presentation
- Pacifichem2015, Dec. 2015, English, Hawaii Convention Center, International conferenceIsothermal crystallization of poly glycolic acid (PGA) by terahertz and Infrared spectroscopyPoster presentation
- Pacifichem2015, Dec. 2015, English, Hawaii Convention Center, International conferenceHydrogen bondings and stereocomplex formation of poly (L-lactic acid) and its poly (D-lactic acid) during isothermal crystallization studied by Raman spectroscopy and X-ray diffractionPoster presentation
- Pacifichem2015, Dec. 2015, English, Hawaii Convention Center, International conferenceCrystal structure and thermal behavior of low molecular weight poly (3-hydroxybutyrate) studied by terahertz and Raman spectroscopyOral presentation
- Pacifichem2015, Dec. 2015, English, Hawaii Convention Center, International conferenceCrystallization and Thermal Behavior of Polly (ε-caprolactone) and its Copolymers Studied by Vibrational Spectroscopy,Poster presentation
- Pacifichem2015, Dec. 2015, English, Hawaii Convention Center, International conferenceCrystallization and chain orientation in the ultrathin films of poly (3-hydroxybutyrate) studied by IR-RAS and GIXDPoster presentation
- シンポジウム テラヘルツ科学の最先端Ⅱ, Nov. 2015, Japanese, 作並温泉, Domestic conferenceラマン分光法とテラヘルツ分光法を用いたPBS(ポリブチレンサクシネート)の結晶相転移Poster presentation
- シンポジウム テラヘルツ 科学の最先端Ⅱ, Nov. 2015, Japanese, 作並温泉, Domestic conferenceラマン、テラヘルツ分光によるポリ乳酸とステレオコンプレックス化したポリ乳酸の構造変化に関する研究Poster presentation
- シンポジウム 科学の最先端Ⅱ, Nov. 2015, Japanese, 作並温泉, Domestic conferenceテラヘルツ分光法を用いた生分解性ポリエステルのUV照射による劣化評価Poster presentation
- シンポジウム テラヘルツ科学の最先端Ⅱ, Nov. 2015, Japanese, 作並温泉, Domestic conferenceTHzイメージングによる生分解性高分子の物性評価Poster presentation
- シンポジウム テラヘルツ科学の最先端Ⅱ, Nov. 2015, English, 作並温泉, Domestic conferenceIntermolecular Interaction of Poly(3-hydroxybutyrate-co-3-hydroxyvalerate)Studied by Low-Frequency Raman and Terahertz SpectroscopyPoster presentation
- 成形加工シンポジア’15, Nov. 2015, English, 福岡大学, Domestic conferenceApplication of FUV spectroscopy for polyethylene Structure analysisOral presentation
- 第64回高分子討論会, Sep. 2015, Japanese, 東北大学 川内キャンパス, Domestic conference振動分光法を用いた低分子量ポリ(3-ヒドロキシブタン酸)の結晶構造及び熱的挙動に関する研究Poster presentation
- 第64回高分子討論会, Sep. 2015, Japanese, 東北大学 川内キャンパス, Domestic conferenceラマン分光法を用いたポリブチレンサクシネートの結晶構造の違いによる酵素分解挙動Poster presentation
- 第64回高分子討論会, Sep. 2015, Japanese, 東北大学 川内キャンパス, Domestic conferenceラマン分光法およびテラヘルツ分光法を用いたポリエチレングリコール(PEG)の 劣化に関する研究Poster presentation
- 第64回高分子討論会, Sep. 2015, Japanese, 東北大学 川内キャンパス, Domestic conferenceテラヘルツ分光法および赤外分光法を用いたポリ(ε-カプロラクトン)の結晶化挙動および熱挙動Poster presentation
- 第64回高分子討論会, Sep. 2015, Japanese, 東北大学 川内キャンパス, Domestic conferenceテラヘルツ分光法およびX線回折法を用いたポリグリコール酸(PGA)の結晶化過程に関する研究Oral presentation
- 第64回高分子討論会, Sep. 2015, Japanese, 東北大学 川内キャンパス, Domestic conferenceテラヘルツ分光による新しい高分子研究の可能性Oral presentation
- 第64回高分子討論会, Sep. 2015, Japanese, 東北大学 川内キャンパス, Domestic conferenceチップ増強ラマン散乱法を用いたポリマーナノコンポジットのナノ構造と分子間相互作用に関する研究Oral presentation
- SCIX2015, Sep. 2015, English, Rhode Island Convention Center, International conferenceThermal Behavior and Lamella Structures of Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) Studied by Low-Frequency Raman,Terahertz Spectroscopy, and Small Angle X-ray ScatteringOral presentation
- 第64回高分子討論会, Sep. 2015, English, 東北大学 川内キャンパス, Domestic conferenceThe crystallization behavior of poly(3-hydroxybutyrate)(PHB) during solvent casting processPoster presentation
- 第64回高分子討論会, Sep. 2015, English, 東北大学 川内キャンパス, Domestic conferenceTemperature Dependent of Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) Studied by Low Frequency Raman and Terahertz SpectroscopyPoster presentation
- 第64回高分子討論会, Sep. 2015, English, 東北大学 川内キャンパス, Domestic conferenceStudy on the Crystallization behavior, Intermediate Phase and Conformation Rearrangement of Poly(3-hydroxybutyrate) Ultrathin Film by Using IR-RAS and GIXDOral presentation
- SCIX2015, Sep. 2015, English, Rhode Island Convention Center, International conferenceStudies of Electronic States of CNT/Rubber Nanocomposites by using Attenuated Total Reflectance Spectroscopy in the Ultraviolet Region;Poster presentation
- SCIX2015, Sep. 2015, English, Rhode Island Convention Center, International conferenceInvestigation of Electronic States of Nano Carbon/Polymer Nanocomposites by Attenuated Total Reflectance-Ultraviolet SpectroscopyPoster presentation
- 第61回高分子研究発表会, Jul. 2015, Japanese, 兵庫県民会館, Domestic conference低分子量ポリ(3-ヒドロキシブタン酸)における結晶構造及び熱的挙動のラマン分光法及びテラヘルツ分光法を用いた研究Poster presentation
- 第61回高分子研究発表会, Jul. 2015, Japanese, 兵庫県民会館, Domestic conference振動分光法を用いたポリカプロラクトンとその共重合体の結晶化挙動に関する研究Poster presentation
- 第61回高分子研究発表会, Jul. 2015, Japanese, 兵庫県民会館, Domestic conference近赤外分光イメージングを用いたポリ乳酸の紫外線劣化による深さ方向分析Oral presentation
- 第61回高分子研究発表会, Jul. 2015, English, 兵庫県民会館, Domestic conferenceStructure and crystallization behavior of Poly (3-hydroxybutyrate) and Poly (D, L-lactide) blends studied by DSC, FTIR and X-ray analysisPoster presentation
- 第61回高分子研究発表会, Jul. 2015, English, 兵庫県民会館, Domestic conferenceCrystallization Behavior and Conformation Rearrangement of Poly(3-hydroxybutyrate) Ultrathin Film Investigated by Infrared Reflection Absorption SpectroscopyOral presentation
- 第61回高分子研究発表会, Jul. 2015, English, 兵庫県民会館, Domestic conferenceAnalysis of Intermolecular Vibration Mode of Poly (3-hydroxybutyrate-co-3-hydroxyvalerate) (P(HB-co-HV)) using Low Frequency Raman and Terahertz SpectroscopyPoster presentation
- プラスチック成形加工学会 第26回年次大会, Jun. 2015, Japanese, タワーホール長堀, Domestic conference生分解性ポリエステルにおける溶融押出混練時の残存結晶量による結晶化促進効果Oral presentation
- XV Chemometrics in Analytical Chemistry, Jun. 2015, English, Changsha,China, International conferenceMultistep Crystallization Process of Poly(3-hydroxybutyrate) Studied by Time-Resolved Synchrotron SAXS and WAXD and MCR[Invited]Invited oral presentation
- 第64回高分子年次大会, May 2015, Japanese, 札幌コンベンションセンター, Domestic conference赤外分光法、広角小角X線回折を用いた低分子量ポリ-3-ヒドロキシブタン酸(PHB)の等温結晶化プロセスの研究Poster presentation
- FR-IR ・ラマン ユーザーズフォーラム2015, May 2015, Japanese, 千里ライフサイエンスセンター, Domestic conference赤外分光法による生分解性高分子の分子間相互作用の研究Public discourse
- 第64回高分子年次大会, May 2015, Japanese, 札幌コンベンションセンター, Domestic conference赤外・ラマン分光法を用いたポリグリコール酸とポリ乳酸の共重合体の分子間相互作用についての研究Poster presentation
- 第64回高分子年次大会, May 2015, Japanese, 札幌コンベンションセンター, Domestic conference振動分光法を用いたポリカプロラクトンとその共重合体の結晶構造および熱挙動に関する研究Poster presentation
- 第64回高分子年次大会, May 2015, Japanese, 札幌コンベンションセンター, Domestic conference振動分光法によるステレオコンプレックス型ポリ乳酸の水素結合に関する研究Oral presentation
- 第64回高分子年次大会, May 2015, Japanese, 札幌コンベンションセンター, Domestic conferenceラマン分光法及びテラヘルツ分光を用いた低分子量ポリ(3-ヒドロキシブタン酸)の結晶構造及び熱的挙動の研究Poster presentation
- 第64回高分子年次大会, May 2015, Japanese, 札幌コンベンションセンター, Domestic conferenceオンライン近赤外分光法による、生分解性ポリエステルにおける、溶融押出混練時の残存結晶量変化による押出成形後の結晶化促進効果の解析Oral presentation
- 第64回高分子年次大会, May 2015, English, 札幌コンベンションセンター, Domestic conferenceConfinement Effect of Chitin on the Crystallization Behavior of Poly(3-hydroxybutyrate)Thin Film Studied by Infrared-Reflection Absorption Spectroscopy and Grazing Incidence X-Ray DiffractionOral presentation
- 第75回分析化学討論会, May 2015, English, 山梨大学甲府キャンパス, Domestic conferenceAnalysis of Poly (3-hydroxbutyrate) during solvent induced crystallization process and its imagesOral presentation
- 第30回近赤外フォーラム, Nov. 2014, Japanese, 筑波大学大学会館, Domestic conference近赤外・赤外分光法とそのシフトイメージングによるポリ乳酸ステレオコンプレックスの結晶構造形成過程の研究Poster presentation
- Biomedical Molecular Imaging 2014, Nov. 2014, English, Taiwan, International conferenceAnalysis of solvent-induced crystallization process of Poly-3-hydroxybutyrate (PHB) by using Near-Infrared Spectroscopy and its imagingPoster presentation
- 第30回近赤外フォーラム, Nov. 2014, English, 筑波大学大学会館, Domestic conferenceAnalysis of solvent-induced crystallization process of Poly-3-hydroxybutyrate (PHB) by using Near-Infrared SpectroscopyPoster presentation
- 第63回高分子討論会, Sep. 2014, Japanese, 長崎大学, Domestic conference低波数ラマン・テラヘルツ分光および量子化学計算を用いたナイロン 6 の低波数振動モードと分子間相互作用の関連性の解明Oral presentation
- 第63回高分子討論会, Sep. 2014, Japanese, 長崎大学, Domestic conference赤外分光法及び量子科学計算を用いた低分子量ポリ-3-ヒドロキシブタン酸の結構造及び熱的挙動の研究Poster presentation
- 第63回高分子討論会, Sep. 2014, Japanese, 長崎大学, Domestic conference赤外/ラマン分光法を用いたポリグリコール酸/ポリ乳酸共重合体の結晶構造とその熱挙動に関する研究Poster presentation
- 第63回高分子討論会, Sep. 2014, Japanese, 長崎大学, Domestic conference近赤外分光法とそのイメージングによるポリ乳酸ステレオコンプレックスの結晶構造形成過程の研究Poster presentation
- 日本分析化学会第63年会, Sep. 2014, Japanese, 広島大学, Domestic conference近赤外分光法とそのイメージングによるpoly L-lactic acid/poly D-lactic acid stereocomplex PLA (SC-PLA)フィルムの結晶構造形成過程の研究Oral presentation
- 第63回高分子討論会, Sep. 2014, Japanese, 長崎大学, Domestic conference近赤外分光を用いたポリ乳酸繊維の生分解および光分解とその風合い変化についての研究Poster presentation
- 第63回高分子討論会, Sep. 2014, Japanese, 長崎大学, Domestic conferenceテラヘルツ分光による高分子の高次構造とダイナミクスの解明Oral presentation
- United States FACSS Annual Meeting, Sep. 2014, English, Grand Sierra Resort, Reno, NV, International conferenceStudy on the Molecular Interaction and its Inhomogeneity in Stereocomplex Crystallization of PLLA/PDLA Blends by using NIR imaging –NIR imaging can provide the molecular interaction and its homogeneity-Poster presentation
- 第63回高分子討論会, Sep. 2014, English, 長崎大学, Domestic conferenceStructure and crystallization behavior of poly(3-hydroxybutyrate) and chitin blends as thin films studied by reflection-absorption infrared spectroscopy and grazing incidence X-ray diffractionPoster presentation
- United States FACSS Annual Meeting, Sep. 2014, English, Grand Sierra Resort, Reno, NV, International conferenceInvestigation of solvent-induced crystallization process of poly (3-hydroxybutyrate) (PHB) by using NIR and its imagingPoster presentation
- United States FACSS Annual Meeting, Sep. 2014, English, Grand Sierra Resort, Reno, NV, International conferenceInvestigation of Crystallinity Change in Poly Lactic Acid during Photodegradable Process by using a Newly Developed Wide Area NIR Camera (Compovision) –Analysis of photolysis process for biodegradable polymer by NIR imaging-Oral presentation
- 第63回高分子討論会, Sep. 2014, English, 長崎大学, Domestic conferenceCrystalline Structure and Thermal Behavior of Poly(butylene succinate) Studied by Infrared and Raman SpectroscopyOral presentation
- 日本分析化学会第63年会, Sep. 2014, English, 広島大学, Domestic conferenceAnalysis of solvent-induced crystallization process of Poly-3-hydroxybutyrate (PHB) by using Near-Infrared SpectroscopyOral presentation
- ICORS2014, Aug. 2014, English, Jena Germany, International conferenceCrystalline Poly - (R) - 3 – Hydroxybutyrate Studied by Raman Raman and Terahertz Spectroscopy and Quantum Mechanical Calculations[Invited]Invited oral presentation
- The International Symposium on Frontier of Terahertz Science 2014, Aug. 2014, English, Domestic conferenceA Study on Low-frequency Vibrational Modes and IntermolecularInteraction of Nylon 6 by Using Low-frequency Raman and Terahertz Spectroscopies Together with Quantum Chemical CalculationOral presentation
- 高分子研究発表会, Jul. 2014, Japanese, 兵庫県民会館, Domestic conference赤外分光法、小角広角X線散乱法を用いた低分子量ポリヒドロキシブタン酸の結晶構造及び熱的挙動の研究Poster presentation
- 高分子研究発表会, Jul. 2014, Japanese, 兵庫県民会館, Domestic conference振動分光法によるジェランガムのゲル化機構に関する研究Poster presentation
- 高分子研究発表会, Jul. 2014, Japanese, 兵庫県民会館, Domestic conference近赤外イメージングを用いたポリ乳酸繊維の生分解性と風合いの変化についてPoster presentation
- MACRO 2014, Jul. 2014, English, Chiang Mai, Thailand, International conferenceIntermolecular Interaction and Thermal Behavior of Polyglycolide Studied by Infrared Spectroscopy and Quantum Chemical CalculationPoster presentation
- MACRO 2014, Jul. 2014, English, Chiang Mai, Thailand, International conferenceIntermolecular Hydrogen Bonding and Gelation Mechanism of GellanGum by Vibrational SpectroscopyPoster presentation
- MACRO 2014, Jul. 2014, English, Chiang Mai, Thailand, International conferenceInfrared Spectroscopy and SAXS/WAXD Studies on Crystal Structures and Thermal Behavior of Low Molecular Weight Poly(3-hydroxybutyrate)Poster presentation
- MACRO 2014, Jul. 2014, English, Chiang Mai, Thailand, International conferenceEvaluation of Soil Biodegradability of Poly(lactic acid) Fabrics by NIR imagingPoster presentation
- 小野市男女共同参画センター, Jun. 2014, Japanese, 小野市うるおい交流館エクラ, Domestic conference小野市男女共同参画センター 平成25年度啓発セミナー講師「未来のリケジョ応援講座」Public discourse
- Asian NIR Symposium, Jun. 2014, English, Korea, International conferenceInvestigation of the molecular interaction and its inhomogeneity in poly L-lactic acid/poly D-lactic acid stereocomplex PLA (SC-PLA) film by using NIR ImagingPoster presentation
- Asian NIR Symposium, Jun. 2014, English, Korea, International conferenceInvestigation of solvent-induced crystallization process of PHB by using NIR and its imagingOral presentation
- 第63回高分子年次大会, May 2014, Japanese, 名古屋国際会議場, Domestic conference赤外分光法、小角広角 X 線散乱法を用いた低分子量ポリヒドロキシブタン酸の結晶構造及び熱的挙動の研究Poster presentation
- 第63回高分子年次大会, May 2014, Japanese, 名古屋国際会議場, Domestic conference赤外分光法を用いたポリブチレンサクシネート(PBS)の結晶構造とその熱挙動の研究Poster presentation
- 第63回高分子年次大会, May 2014, Japanese, 名古屋国際会議場, Domestic conference振動分光法を用いたジェランガムのゲル化機構についての研究Poster presentation
- 第63回高分子年次大会, May 2014, Japanese, 名古屋国際会議場, Domestic conference振動分光法および量子化学計算を用いたポリグリコール酸の分子間相互作用に関する研究Poster presentation
- 第74回分析化学討論会, May 2014, Japanese, 日本大学工学部(福島), Domestic conference近赤外イメージング装置(Compovision)を用いたポリ乳酸の光分解過程モニタリングOral presentation
- 第63回高分子年次大会, May 2014, Japanese, 名古屋国際会議場, Domestic conference近赤外イメージングを用いたポリ乳酸繊維の生分解性と風合いについての研究Poster presentation
- 第74回分析化学討論会, May 2014, Japanese, 日本大学工学部(福島), Domestic conference近赤外イメージングを用いたpoly-L-lactic acid(PLLA)/poly-D-lactic acid(PDLA)ステレオコンプレックス(SC-PLA)フィルムの混合不均一性の解明Poster presentation
- 第74回分析化学討論会, May 2014, English, 日本大学工学部(福島), Domestic conferenceInvestigation of Solvent-Induced Crystallization Process of Poly(3-hydroxybutyrate) by using Near Infrared Spectroscopy and Its ImagingPoster presentation
- 平成25年度本分光学会年次講演会, Nov. 2013, Japanese, 東京工業大学, Domestic conference低波数ラマン、テラヘルツ分光及び量子化学計算を用いたポリグリコール酸の分子間相互作用に関する研究Poster presentation
- 日本分光学会年次講演会, Nov. 2013, Japanese, Domestic conference減衰全反射遠紫外分光法によるポリエチレンの表面構造の研究―作製方法の違いおよび温度依存性―Poster presentation
- テラヘルツ分光法の最先端 Ⅶ, 日本分光学会, Oct. 2013, Japanese, Domestic conference低波数ラマン、テラヘルツ分光及び量子化学計算を用いたポリグリコール酸の分子間相互作用に関する研究Poster presentation
- 分析化学会第62年会, Sep. 2013, Japanese, Domestic conference低波数ラマン,テラヘルツ分光及び量子化学計算を用いたナイロン6の温度変化に伴う構造変化に関する研究Oral presentation
- 高分子討論会, Sep. 2013, Japanese, Domestic conference低波数ラマン、テラヘルツ分光及び量子化学計算によるナイロン6の温度変化に伴う分子間相互作用及び構造変化に関する研究Poster presentation
- 高分子討論会, Sep. 2013, Japanese, Domestic conference赤外、ラマン分光法と量子化学計算を用いたポリブチレンサクシネートの結晶構造と結晶相転移の研究Oral presentation
- 高分子討論会, Sep. 2013, Japanese, Domestic conference振動分光法・X線回折法・量子力学計算を用いたポリグリコール酸の分子間相互作用と熱挙動に関する研究Oral presentation
- 繊維学会秋季研究発表会, Sep. 2013, Japanese, Domestic conference振動分光法および量子化学計算を用いたポリブチレンサクシネートの延伸による結晶相転移の研究Poster presentation
- 分析化学会第62年会, Sep. 2013, Japanese, Domestic conference固体極表面用減衰全反射遠紫外分光法を用いたポリエチレンの熱挙動に関する研究Poster presentation
- 高分子討論会, Sep. 2013, Japanese, Domestic conference近赤外イメージング分光法を用いたポリ乳酸繊維の生分解性評価Poster presentation
- 繊維学会秋季研究発表会, Sep. 2013, Japanese, Domestic conferenceポリヒドロキシブタン酸における弱い水素結合が結晶構造安定化と熱的挙動に果たす役割Oral presentation
- 高分子討論会, Sep. 2013, Japanese, 金沢大学, Domestic conference41.振動分光法・X線回折法・量子力学計算を用いたポリグリコール酸の分子間相互作用と熱挙動に関する研究Oral presentation
- Seventh International Conference on Advanced Vibrational Spectroscopy (ICAVS-7), Aug. 2013, English, International conferenceTip-enhanced Raman spectroscopic study of the property of carbon nanotubes in polystyrene/singlewall carbon nanotubes nanocompositesOral presentation
- Seventh International Conference on Advanced Vibrational Spectroscopy (ICAVS-7), Aug. 2013, English, International conferenceTerahertz Vibrational Spectroscopy of Poly(3-hydroxybutyrate) and Nylon,Oral presentation
- Seventh International Conference on Advanced Vibrational Spectroscopy (ICAVS-7), Aug. 2013, English, International conferenceTemperature-dependent Structural Changes and Intermolecular Hydrogen Bonds in Nylon 6 Studied by Low-frequency Raman and Terahertz Spectroscopies and Quantum Chemical CalculationPoster presentation
- Seventh International Conference on Advanced Vibrational Spectroscopy (ICAVS-7), Aug. 2013, English, International conferenceStudy on Crystallization Behavior and Intermolecular Interactions in Biodegradable Blend Between Poly(3-hydroxybutyrate) and ChitinPoster presentation
- Seventh International Conference on Advanced Vibrational Spectroscopy (ICAVS-7), Aug. 2013, English, International conferenceLow-Frequency Raman and THz Spectroscopy of polystyrenePoster presentation
- Seventh International Conference on Advanced Vibrational Spectroscopy (ICAVS-7), Aug. 2013, English, International conferenceIsothermal Crystallization of Poly(3-hydroxybutyrate) and Cellulose Acetate Butyrate Blends studied by IR and NIR ImagingPoster presentation
- Seventh International Conference on Advanced Vibrational Spectroscopy (ICAVS-7), Aug. 2013, English, International conferenceIntermolecular Interaction and Thermal Behavior of Polyglycolide Studied by Low Frequency Raman Spectroscopy and Quantum Chemical CalculationPoster presentation
- Seventh International Conference on Advanced Vibrational Spectroscopy (ICAVS-7), Aug. 2013, English, International conferenceGelation Mechanism of Gellan Gum Studied By Infrared SpectroscopyPoster presentation
- Seventh International Conference on Advanced Vibrational Spectroscopy (ICAVS-7), Aug. 2013, English, International conferenceCrystal Structures and Thermal Behavior of Polyhydroxyalkanoates Studied by Infrared Spectroscopy and Wide Angle X-ray DiffractionOral presentation
- Seventh International Conference on Advanced Vibrational Spectroscopy (ICAVS-7), Aug. 2013, English, International conferenceCrystal Structures and Thermal Behavior of Low Molecular Weight Poly(3-Hydroxybutyrate) Studied by Infrared Spectroscopy and Wide Angle X-Ray DiffractionPoster presentation
- Seventh International Conference on Advanced Vibrational Spectroscopy (ICAVS-7), Aug. 2013, English, International conferenceCrystalline Transition Mechanism and Thermal Behavior of Poly(butylene succinate) Studied by IR, Raman Spectroscopy and Quantum Chemical CalculationPoster presentation
- Seventh International Conference on Advanced Vibrational Spectroscopy (ICAVS-7), Aug. 2013, English, International conferenceCorrelation between the Torsional Motion of Methyl Groups and the Weak Intermolecular Hydrogen Bonds Based on the Temperature-dependent Raman Spectra of Biodegradable Poly(3-hydroxybutyrate)Poster presentation
- Seventh International Conference on Advanced Vibrational Spectroscopy (ICAVS-7), Aug. 2013, English, International conferenceBiodegradability and Handle of Poly(lactic acid) FabricsPoster presentation
- 高分子研究会発表, Jul. 2013, Japanese, Domestic conference低波数ラマンと量子力学計算によるポリグリコール酸の分子間相互作用に関する研究Poster presentation
- 19th European Symposium on Polymer Spectroscopy (ESOPS19), Jul. 2013, English, International conferenceTemperature-dependent structural changes and intermolecular hydrogen bonds in Nylon 6 studied by low-frequency Raman and Terahertz spectroscopies and Quantum chemical calculationPoster presentation
- 高分子研究会発表会, Jul. 2013, English, Domestic conferenceTemperature-dependent Fourier Transform Infrared Spectroscopy and Raman Spectroscopy of Biodegradable Poly(3-hydroxybutyrate)Oral presentation
- 19th European Symposium on Polymer Spectroscopy (ESOPS19), Jul. 2013, English, International conferenceIntermolecular vibrational modes of crystalline poly-(R)-3-hydroxybutyratePoster presentation
- 19th European Symposium on Polymer Spectroscopy (ESOPS19), Jul. 2013, English, International conferenceIntermolecular Interactions of Polyglycolic acid Studied by Vibrational Spectroscopy, Wide Angle X-ray Diffraction, and Quantum Chemical CalculationOral presentation
- 高分子研究会発表会, Jul. 2013, English, Domestic conferenceIntermolecular Interaction and Crystallization Behavior of Poly(3-hydroxybutyrate) and Chitin Blends Studied by Vibrational Spectroscopy and Wide-Angle X-ray DiffractionPoster presentation
- 19th European Symposium on Polymer Spectroscopy (ESOPS19), Jul. 2013, English, International conferenceGelation mechanism of gellan gum studied by infrared and Raman spectroscopyPoster presentation
- 19th European Symposium on Polymer Spectroscopy (ESOPS19), Jul. 2013, English, International conferenceCrystalline structure and thermal behavior of poly(butylene succinate) studied by Raman spectroscopy and quantum chemical calculationsPoster presentation
- The 3rd discussion meeting on advanced Polymer, Jun. 2013, English, International conferenceRole of Hydrogen Bonding of Poly(3-hydroxybutyrate) Studied by Infrared Spectroscopy and Wide Angle X-ray Diffraction[Invited]Invited oral presentation
- ICNIRS '13, Jun. 2013, English, International conferenceApplication of a High Speed Hyper-spectral NIR Camera (Compovision) for Polymer Material Industries-Quantitative Analysis of Crystallinity of poly-L-lactic acid (PLLA)-Poster presentation
- 高分子学会年次大会, May 2013, Japanese, Domestic conference低波数ラマン、テラヘルツ分光及びX線回折によるナイロンの温度依存構造変化及び水素結合に関する研究Poster presentation
- 高分子学会年次大会, May 2013, Japanese, Domestic conference低波数ラマンと量子力学計算を用いたポリグリコール酸の分子間相互作用に関する研究Poster presentation
- 第73回分析化学討論会, May 2013, Japanese, Domestic conference低波数ラマン, テラヘルツ分光, 量子化学計算によるナイロンの低波数スペクトル解析Oral presentation
- 高分子学会年次大会, May 2013, Japanese, 京都国際会議場, Domestic conference赤外ラマン分光法及び量子化学計算によるポリブチレンサクシネート(PBS)の結晶構造と熱挙動の研究Poster presentation
- 第73回分析化学討論会, May 2013, Japanese, Domestic conference減衰全反射遠紫外分光法を用いたポリエチレンのスペクトルと表面構造の研究Oral presentation
- 高分子学会年次大会, May 2013, English, Domestic conferenceTemperature Dependence of Vibrational Spectroscopic study of Poly(3-hydroxybutyrate)Oral presentation
- 高分子学会年次大会, May 2013, English, Domestic conferenceInvestigation of Intermolecular Interaction and Crystallization Behavior of Blends between Poly(3-hydroxybutyrate) and Chitin Based on the Thermal Properties, X-ray Scattering and Vibrational Spectroscopic MeasurementsPoster presentation
- 高分子学会年次大会, May 2013, Japanese, Domestic conferenceFT-IRおよびFT-NIRイメージング分光法によるポリヒドロキシブタン酸/セルロース誘導体の球晶における水素結合の影響Poster presentation
- 日本化学会年会, Mar. 2013, Japanese, Domestic conference減衰全反射遠紫外分光法を用いたポリエチレンを主鎖にもつ接着樹脂の表面構造の研究Oral presentation
- 近赤外フォーラム, Mar. 2013, Japanese, Domestic conferenceコンポビジョンによる生分解性マルチフィルム材料(ポリ乳酸)の結晶化度評価に関する研究Poster presentation
- The 9th SPSJ International Polymer Conference (IPC2012), Dec. 2012, English, Kobe, JAPAN, International conferenceVibrational spectroscopy study on carbon nanotube/polymer nanocompositesPoster presentation
- The 9th SPSJ International Polymer Conference, Dec. 2012, English, Kobe, JAPAN, Domestic conferenceTip-enhanced Raman spectroscopy study of intermolecular interactions and molecular orientation at interface of styrene-butadiene rubber/multiwall carbon nanotubes nanocompositesOral presentation
- The 9th SPSJ International Polymer Conference (IPC2012), Dec. 2012, English, Kobe, JAPAN, Domestic conferenceSimultaneous Synchrotron SAXS/WAXD Study of Composition Fluctuations, Cold-Crystallization, and Melting in Biodegradable Polymer Blends of Cellulose Acetate Butyrate and Poly(3-hydroxybutyrate)Oral presentation
- The 9th SPSJ International Polymer Conference (IPC2012), Dec. 2012, English, Kobe, Japan, Domestic conferenceGelation Mechanism and Hydrogen Bonding Behavior of Gellan Gum Studied by Vibrational Spectroscopy and Small Angle X-ray ScatteringPoster presentation
- The 9th SPSJ International Polymer Conference (IPC2012), Dec. 2012, English, Kobe, JAPAN, Domestic conferenceFT-IR and FT-NIR Imaging Spectroscopy Studies on Effects of Hydrogen Bond Intermolecular Interactions of Poly(3-hydroxybutyrate) and Cellulose Acetate Butyrate BlendsPoster presentation
- The 9th SPSJ International Polymer Conference (IPC2012), Dec. 2012, English, Kobe, JAPAN, Domestic conferenceCrystal Structure and Thermal Behavior of Polyglycolide Studied by Vibrational Spectroscopy, Wide Angle X-ray Diffraction, and Quantum Chemical CalculationPoster presentation
- The 9th SPSJ International Polymer Conference (IPC2012), Dec. 2012, English, Kobe, JAPAN, Domestic conferenceCrystal Structure and Thermal Behavior of Biodegradable Polymer Blends of Poly(3-hydroxybutyrate) and Chitin Studied by Infrared Spectroscopy and Wide Angle X-ray DiffractionPoster presentation
- The 9th SPSJ International Polymer Conference (IPC2012) De, Dec. 2012, English, Domestic conferenceCrystalline Structure and Thermal Behavior of Poly(butylene succinate) and Poly(butylene succinate-co-adipate) Studied by Infrared Spectroscopy and Wide Angle X-ray DiffractionPoster presentation
- International Symposium on Frontiers in THz Technology, Nov. 2012, English, Nara, Japan, Domestic conferenceTerahertz Absorption Spectra of Nylons for Various Crystalline ConformationsPoster presentation
- FACCS 2012, Oct. 2012, English, KANSAS CITY, MO, International conferenceTwo-Dimensional Correlation Spectroscopy of Polymer in Terahertz Frequency RegionOral presentation
- FACCS 2012, Oct. 2012, English, KANSAS CITY, MO, International conferenceIntermolecular Vibrations of poly-(R)-3-hydroxybutyrate in Low-Frequency Raman and THz Time-Domain Spectra Explored by DFT Calculation with Cartesian Coordinate Tensor TransferPoster presentation
- The Federation of Analytical Chemistry and Spectroscopy Societies (FACSS), Oct. 2012, English, Kansas City, MO, United States, International conferenceExtreme Surface Analysis of Polyethylenes by Attenuated Total Reflection Far-ultraviolet Spectroscopy ― Comparison with Atomic Force Microscope Measurement ―Poster presentation
- The Federation of Analytical Chemistry and Spectroscopy Societies (FACSS), Oct. 2012, English, Kansas City, MO, United States, International conferenceCrystal Structure and Thermal Behavior of Polyglycolide Studied by Vibrational Spectroscopy, Wide Angle X-ray Diffraction, and Quantum Chemical CalculationPoster presentation
- FACCS 2012, Oct. 2012, English, KANSAS CITY, MO, International conferenceCrystallinity Evaluation of a Biodegradable Polymer by using the new NIR Camera (Compovision) Developed for High Speed Wide Area MeasurementPoster presentation
- 第6回分子科学討論会, Sep. 2012, Japanese, 東京大学本郷キャンパス, Domestic conference低波数ラマン分光と量子化学計算による高分子の振動解析Poster presentation
- 第61回高分子討論会, Sep. 2012, Japanese, 名古屋工業大学, Domestic conference振動分光法・X 線回折法・量子化学計算によるポリグリコール酸の結晶構造と熱挙動の研究Poster presentation
- 第61回高分子討論会, Sep. 2012, Japanese, 名古屋工業大学, Domestic conference振動分光法および小角X線散乱法を用いたジェランガムのゲル化過程に関する研究Oral presentation
- 第6回分子科学討論会, Sep. 2012, Japanese, 東京大学本郷キャンパス, Domestic conference減衰全反射遠紫外分光法によるナイロン極表面の電子状態の研究Oral presentation
- 分析化学会第61年会, Sep. 2012, Japanese, 金沢大学角間キャンパス, Domestic conference減衰全反射遠紫外スペクトルによるポリエチレンの極表面分析―AFM測定との比較―Oral presentation
- 第6回分子科学討論会, Sep. 2012, Japanese, 東京大学本郷キャンパス, Domestic conferenceポリエチレン表面の電子状態の研究Poster presentation
- 第6回分子科学討論会, Sep. 2012, Japanese, 東京大学本郷キャンパス, Domestic conferenceテラヘルツ周波数領域における高分子の振動分光Oral presentation
- 第61回高分子討論会, Sep. 2012, English, 名古屋工業大学, Domestic conferenceVibrational Spectroscopy study of Carbon Nanotube based Polymer NanocompositsPoster presentation
- The 37th The International Conference on Infrared, Millimeter, and Terahertz Waves (IRMMW-THz), Sep. 2012, English, Wollongong, Australia, International conferenceVibrational spectra of nylon-6, nylon-6/6, nylom-11 and nylon-12 studied by terahertz spectroscopyOral presentation
- 第61回高分子討論会, Sep. 2012, English, 名古屋工業大学, Domestic conferenceTerahertz spectroscopy of nylon-6,nylon-6/6, nylom-11 and nylon-12Oral presentation
- 第61回高分子討論会, Sep. 2012, English, 名古屋工業大学, Domestic conferenceSAXS/WAXD Study of CompositionFluctuations, Cold-Crystallization, and Melting in Cellulose Acetate Butyrate and Poly(3-hydroxybutyrate) blendsOral presentation
- The 9th SPSJ International Polymer Conference (IPC2012), Sep. 2012, English, Kobe, JAPAN, International conferenceElectronic States on Extreme Surface of Polymers Studied by Using Attenuated Total Reflection Spectroscopy in Far Ultraviolet RegionPoster presentation
- RSC Tokyo International Conference - Micro/Nano Technologies for Analysis of Human Health and Diagnostics -, Sep. 2012, English, Makuhari Messe, Chiba, International conferenceAttenuated Total Reflection Spectroscopy in Far Ultraviolet Region (ATR-FUV) for Extreme Surface of PolymersPoster presentation
- 白樺夏季大学, Aug. 2012, Japanese, 草津セミナーハウス, Domestic conference振動分光法で生分解性高分子の構造と相互作用を探るInvited oral presentation
- 第58回高分子研究発表会(神戸), Jul. 2012, Japanese, 兵庫県民会館, Domestic conference赤外分光法とX線回折法によるポリグリコール酸の結晶構造と熱挙動に関する研究Poster presentation
- 第58回高分子研究発表会(神戸), Jul. 2012, Japanese, 兵庫県民会館, Domestic conferenceジェランガムのゲル化におけるpHの影響Poster presentation
- 第58回高分子研究発表会(神戸), Jul. 2012, English, 兵庫県民会館, Domestic conferenceLaser heating effect study to Multi-Wall Carbon Nanotube and Styrenen-Butadiene Rubber/ Multi-Wall Carbon nanotube compositesPoster presentation
- 第61回高分子学会年次大会, May 2012, Japanese, パシフィコ横浜, Domestic conference赤外分光法を用いたP(MMA-co-MA)における水素結合とその熱挙動の研究Poster presentation
- 第61回高分子学会年次大会, May 2012, Japanese, パシフィコ横浜, Domestic conference赤外分光法とX線回折法によるポリグリコール酸の結晶構造と熱挙動に関する研究Poster presentation
- 第61回高分子学会年次大会, May 2012, Japanese, パシフィコ横浜, Domestic conference時間分解小角・広角X 線散乱測定によるポリヒドロキシブタン酸の結晶化過程の研究Poster presentation
- 第72回分析化学討論会, May 2012, Japanese, 鹿児島大学工学部 郡元キャンパス, Domestic conference減衰全反射遠紫外分光法を用いたポリエチレンのスペクトルと表面構造の研究Poster presentation
- 第61回高分子学会年次大会, May 2012, Japanese, パシフィコ横浜, Domestic conferenceジェランガムのゲル化におけるpHの影響Poster presentation
- 11th European Symposium on Polymer Blends, Mar. 2012, English, Donostia - San Sebastian, International conferenceStyrene-Butadiene Rubber/Multiwall Carbon Nanotubes Nanocomposites Studied by Raman SpectroscopyPoster presentation
- 11th European Symposium on Polymer Blends, Mar. 2012, English, Donostia - San Sebastian, Spain, International conferenceCrystal Structures and Thermal Behavior of Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) Studied by Infrared Spectroscopy and Wide Angle X-ray DiffractionOral presentation
- 第1回FSBL研究発表会, Nov. 2011, Japanese, 大阪国際会議場, Domestic conference時間分解SAXS/WAXDによるポリヒドロキシブタン酸の結晶化初期過程の研究Poster presentation
- The 12th Pacific Polymer Conference (PPC12), Nov. 2011, English, The Shilla Hotel, Jeju, Korea, International conferenceTime-Resolved Synchrotron SAXS and WAXD Studies on Morphological Evolutions of Poly(3-hydroxybutyrate) during Isothermal CrystallizationOral presentation
- The 12th Pacific Polymer Conference (PPC12), Nov. 2011, English, The Shilla Hotel, Jeju, Korea, International conferenceRaman Spectra of Styrene-Butadiene Rubber/Multiwall Carbon Nanotubes Nanocomposites,Poster presentation
- The 12th Pacific Polymer Conference (PPC12), Nov. 2011, English, The Shilla Hotel, Jeju, Korea, International conferenceInter- and Intramolecular Hydrogen Bonding Change by Structural Formation of Gellan Gum studied by Vibrational SpectroscopyPoster presentation
- The 12th Pacific Polymer Conference (PPC12), Nov. 2011, English, The Shilla Hotel, Jeju, Korea, International conferenceInfrared Spectroscopy and Wide Angle X-ray Diffraction studies of Crystal Structures and Thermal Behavior of Poly(3-hydroxybutyrate-co-3-hydroxyvalerate)Oral presentation
- The 12th Pacific Polymer Conference (PPC12), Nov. 2011, English, The Shilla Hotel, Jeju, Korea, International conferenceA Raman Study on Intermolecular Interaction at the Interface of Polystyrene/ Carbon Nanotubes Nanocomposites,Poster presentation
- 2011 IEEE CEIDP (IEEE CONFERENCE ON ELECTRICAL INSULATION AND DIELECTRIC PHENOMENA), Oct. 2011, English, Hyatt Regency Cancun, Mexico, International conferenceTerahertz Spectroscopy of Poly(3-Hydroxyalkanote)sPoster presentation
- 36th International Conference on Infrared, Millimeter and Terahertz Waves (IRMMW-THz 2011), Oct. 2011, English, Houston, USA, International conferenceIsothermal crystallization of poly(3-hydroxybutyrate) studied by terahertz two-dimensional correlation SpectroscopyOral presentation
- 36th International Conference on Infrared, Millimeter and Terahertz Waves (IRMMW-THz 2011), Oct. 2011, English, Houston, USA, International conferenceIsothermal crystallization of poly(3-hydroxybutyrate) studied by terahertz time-domain spectroscopyPoster presentation
- FACSS 2011, Oct. 2011, English, Grand Sierra Resort, Reno, USA, International conferenceCrystallization of Poly(3-Hydroxybutyrate) Studied by Terahertz Two-Dimensional Correlation SpectroscopyPoster presentation
- 第60回高分子討論会, Sep. 2011, Japanese, 岡山大学, Domestic conference振動分光法を用いたジェランガムの構造形成と分子間・分子内水素結合の変化に関する研究Poster presentation
- 第60回高分子討論会, Sep. 2011, Japanese, 岡山大学, Domestic conferenceラマン分光法を用いたポリマーナノコンポジットの界面における分子間相互作用の研究Oral presentation
- 第60回高分子討論会, Sep. 2011, Japanese, 岡山大学, Domestic conferenceポリヒドロキシアルカン酸の結晶構造形成における弱い水素結合の役割Public discourse
- 第72回応用物理学会学術講演会, Sep. 2011, Japanese, 山形大学, Domestic conferenceテラヘルツ分光によるポリヒドロキシ酪酸の等温結晶成長の研究Oral presentation
- 日本分光学会テラヘルツ分光部会シンポジウム,テラヘルツ分光の最前線V~バイオテラヘルツ分光~, Sep. 2011, Japanese, パシフィコ横浜, Domestic conferenceテラヘルツ二次元相関分光法によるポリマーの構造研究Poster presentation
- 第72回応用物理学会学術講演会, Sep. 2011, Japanese, 山形大学, Domestic conferenceテラヘルツ周波数領域におけるポリマーの二次元相関分光Oral presentation
- 第57回高分子研究発表会, Jul. 2011, English, 兵庫県民会館,神戸, Domestic conferenceラマン分光法を用いたポリマーナノコンポジットにおける界面の構造と物性Poster presentation
- THz Science and Tachnology ~The Castle Meeting~, Jul. 2011, English, Schloss Rauischholzhausen, Marburg, Germany, International conferenceTwo dimensional correlation spectroscopy in terahertz frequency regionPoster presentation
- 第57回高分子研究発表会, Jul. 2011, Japanese, 兵庫県民会館、神戸, Domestic conferenceThermal Behavior and Phase Structures of Poly(3-hydroxybutyrate) and Poly(4-vinylphenol) BlendsOral presentation
- Sixth International Conference on Advanced Vibrational Spectroscopy (ICAVS-6), Jun. 2011, English, Sonoma, California, International conferenceThermal Behavior and Lamella Structures of Poly(3-hydroxybutyrate-co-3- hydroxyvalerate) (P(HB-co-HV)) Studied by Infrared SpectroscopyPoster presentation
- Sixth International Conference on Advanced Vibrational Spectroscopy (ICAVS-6), Jun. 2011, English, Sonoma, California, International conferenceTemperature-Dependent FT-IR Imaging Spectroscopy of Phase-Separation in a Poly(3-hydroxybutyrate)/Poly(L-lactic Acid) (50:50 wt.%) BlendPoster presentation
- Sixth International Conference on Advanced Vibrational Spectroscopy (ICAVS-6),, Jun. 2011, English, Sonoma, California, International conferenceRaman Spectra of Styrene-Butadiene Rubber/Multiwall Carbon Nanotubes NanocompositesPoster presentation
- Sixth International Conference on Advanced Vibrational Spectroscopy (ICAVS-6), Jun. 2011, English, Sonoma. California, International conferenceCrystallization Behavior of Poly(3-hydroxybutyrate), Polycaprolactone and their Blend (50:50 wt.%) Studied by 2D FT-IR Correlation SpectroscopyPoster presentation
- Sixth International Conference on Advanced Vibrational Spectroscopy (ICAVS-6), Jun. 2011, English, Sonoma, California, International conferenceA TERS Study on Polymer NanocompositesPublic discourse
- 第60回高分子学会年次大会, May 2011, Japanese, 大阪国際会議場, Domestic conference赤外分光法によるジェランガムのゲル化に伴う分子間・分子内水素結合の変化に関する研究Poster presentation
- 第60回高分子学会年次大会, May 2011, Japanese, 大阪国際会議場, Domestic conference振動分光法によるポリマーコンポジットの分子間相互作用の研究Poster presentation
- 第60回高分子学会年次大会, May 2011, Japanese, 大阪国際会議場, Domestic conferenceラマン分光法を用いたSBR/カーボンナノチューブナノコンポジットにおける界面の構造と物性Poster presentation
- 第60回高分子学会年次大会, May 2011, Japanese, 大阪国際会議場, Domestic conferenceテラヘルツ周波数領域における高分子構造の分光学的研究Oral presentation
- International Congress on Analytical Sciences (ICAS) 2011, May 2011, English, Kyoto, Japan, International conferenceTwo Dimensional Correlation Spectroscopy in Terahertz Frequency RegionPoster presentation
- International Congress on Analytical Sciences (ICAS) 2011, May 2011, English, Kyoto, Japan, International conferenceTip Enhanced Raman Scattering (TERS) Study of Styrene-Butadiene Rubber/Multiwall Carbon Nanotubes NanocompositesOral presentation
- International Congress on Analytical Sciences (ICAS) 2011, May 2011, English, Kyoto, Japan, International conferenceSpectroscopy of Poly(3-hydroxyalkanoate)s in Terahertz Frequency RegionOral presentation
- International Congress on Analytical Sciences (ICAS) 2011, May 2011, English, Kyoto, Japan, International conferenceExcitation Wavelength Dependence of Resonance Raman Spectra of Styrene-Butadiene Rubber/Multiwall Carbon Nanotubes NanocompositesPoster presentation
- 第60回高分子学会年次大会, May 2011, English, 大阪国際会議場, Domestic conferenceCrystal Structure, Thermal Behavior and Hydrogen Bonding Interactions of Biodegradable Polymer Poly(3-hydroxybutyrate) Blended with Poly(4-vinylphenol)Oral presentation
- International Congress on Analytical Sciences (ICAS) 2011, May 2011, English, Kyoto, Japan, International conferenceCrystallization Behavior of Poly(3-hydroxybutyrate) (PHB), Poly(ε-caprolactone) (PCL) and their Blend (50:50 wt.%) Studied by 2D FT-IR Correlation SpectroscopyPoster presentation
- The 2010 International Chemical Congress of Pacific Basin Societies (Pacifichem2010), Dec. 2010, English, Honolulu, Hawaii, USA, International conferenceTip-enhanced Raman scattering studies on polymer thin filmsPoster presentation
- The 2010 International Chemical Congress of Pacific Basin Societies (Pacifichem2010), Dec. 2010, English, Honolulu, Hawaii, USA, International conferenceSpecific crystal structure of poly(3-hydroxybutyrate) thin films studied by infrared reflection-absorption spectroscopyOral presentation
- The 2010 International Chemical Congress of Pacific Basin Societies (Pacifichem2010), Dec. 2010, English, Honolulu, Hawaii, USA, International conferenceInfrared spectroscopy study on intermolecular interaction and phase separation of PS/PVME polymer blendsPoster presentation
- 理研・分子研合同シンポジウム 第11回エクストリームフォトニクス研究, Oct. 2010, English, 和光市, Domestic conferenceHigher Order Conformation of Poly(3-hydroxyalkanote)s Studied by Terahertz Time-Domain SpectroscopyPoster presentation
- International Symposium on Frontier of Terahertz Spectroscopy IV -Innovations in THz Spectroscopy and THz-Wave Wireless Communications, Oct. 2010, English, Matsumoto, Japan, International conferenceHigher Order Conformation of Poly(3-hydroxyalkanote)s Studied by Terahertz Time-Domain SpectroscopyPoster presentation
- EOS Annual Meeting 2010 (EOSAM 2010), Oct. 2010, English, Parc Floral de Paris, France, International conferenceHigher Order Conformation of Poly(3-hydroxyalkanote)s Studied by Terahertz SpectroscopyOral presentation
- ICAVS2017, Jun. 2007, English, Victoria Conference Centre, International conferenceThermal Denaturation and structual changes of collagen model peptide studied by low frequency Raman and THz spectroscopyPoster presentation
- 第66回高分子年次大会, May 2007, Japanese, 幕張メッセ, Domestic conferenceラマン・テラヘルツ分光法を用いたステレオコンプレックス型ポリ乳酸の紫外線劣化評価Poster presentation
- 日本赤外線学会Oct. 2021 - Present
- Royal Society of ChemistryOct. 2021 - Present
- the Spectroscopical Society of JapanAug. 2014 - Present
- The Chemical Society of Japan (CSJ)Apr. 2010 - Present
- The Japan of Society of Analitical ChemistrySep. 2006 - Present
- The Society of Polymer Science, Japan (SPSJ)Mar. 2000 - Present
- Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (B), Grant-in-Aid for Scientific Research (B), Kobe University, 01 Apr. 2020 - 31 Mar. 2023Direct observation of Intermolecular Interaction of polymers by low-frequency Raman spectroscopy
- Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (C), Grant-in-Aid for Scientific Research (C), University of Hyogo, 01 Apr. 2017 - 31 Mar. 2020Granulated sugar is a crystalline substance with 99.9 % purity. However, some granulated sugars have different melting characteristics. Melting point determination showed the necessity of measuring both melt-starting and melt-ending temperatures to evaluate their melting characteristics. The difference of melting points among granulated sugars affected the quality of processed food like candy and caramel sauce, but when they were processed with granulated sugars completely dissolved in water, there was no difference in their quality. The result indicates that the difference of melting points among granulated sugars is due to the difference of their crystal structure. Soft X-ray absorption spectroscopy and THz-Raman spectroscopy indicated the existence of different chemical states among granulated sugars. The observations of microbeam X-ray diffraction suggested the existence of crystal domains with different orientations and crystallinity.
- Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research Grant-in-Aid for Young Scientists (B), Grant-in-Aid for Young Scientists (B), Osaka University, 01 Apr. 2017 - 31 Mar. 2019It is important to analyze the higher-order structures of crystalline polymers in relation to their structures and functions. The low-frequency vibrational spectroscopies are sensitive to the polymer structures and can be simple analytical methods of them. However, the low-frequency modes haven’t been fully assigned yet. Here, we successfully developed a low-frequency Raman spectrometer and achieved the assignments of the low-frequency modes of nylon 6, a typical crystalline polyamide, by applying a fragment-based DFT calculation to the spectral interpretation.
- Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (A), Grant-in-Aid for Scientific Research (A), Kwansei Gakuin University, 01 Apr. 2015 - 31 Mar. 2018We carried out ATR and quantum chemical calculation study of electronic spectra of graphene in FUV-DUV region. The absorption of graphene appears in the DUV region, however, we observed a new peak in the FUV region. Based on the results of TD-DFT and ZINDO calculations, it was possible to reproduce the spectral variations. These studies provide insights on the origins of the spectral variability of graphene as well as the molecular orbitals involved in FUV transition of graphene. We also performed an ATR-FUV-DUV study of PHB and its nanocomposite with graphene. The major absorption of polymer occurs in FUV. The structural changes upon formation of the nanocomposite and heating cause spectral variations. The FUV absorption of the relaxed structures was determined to be significantly stronger than that of the crystalline state. These results are consistent with the observed temperature-dependent spectra of the pure PHB.
- 学術研究助成基金助成金/基盤研究(C), Apr. 2015 - Mar. 2018, Principal investigatorCompetitive research funding
- 研究成果展開事業(産学共創基礎基盤研究プログラム), 2016, Principal investigatorテラヘルツイメージング分光による高分子材料の劣化の可視化と深さ方向分析Competitive research funding
- Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (B), Grant-in-Aid for Scientific Research (B), Kwansei Gakuin University, 01 Apr. 2011 - 31 Mar. 2014We have developed an attenuated total reflection-far-ultraviolet spectrometer for a solid ultra surface. This instrument enables us to explore the surface (-50 nm) structure of a bulk solid sample. As applications we measured ATR-FUV spectra (145-250 nm) of various kinds of polyethylenes and Nylons. Based on a comparison of the ATR spectra of polyethylenes with different densities with the corresponding transmittance spectra and that with spectra of liquid and solid n-alkans we obtained the correlation between electronic structure and surface structure. For Nylons we have carried out similar studies. For both cases we have used quantum chemical calculations to investigate band assignments and the relation between spectra and structure. In this way we have succeeded in developing the novel method for solid ultra surface.
- 科学研究費補助金/基盤研究(C), Apr. 2011 - Mar. 2014, Principal investigatorCompetitive research funding
- Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (C), Grant-in-Aid for Scientific Research (C), Kwansei Gakuin University, 2008 - 2010The purpose of this study is to investigate C-H…O=C hydrogen bondings and thermal behavior of biodegradable polyhydroxyalkanoates by using IR and Raman spectroscopy and quantum chemical calculation studies. It is very likely that the C-H…O=C hydrogen bondings break much more easily in P(HB-co-HHx) copolymer than in PHB because of the bulkiness of large amounts of amorphous parts. However, the polymer chains still keep the lamella structure even in the copolymers with the HHx (long side chain unit) content of more than several percent. The crystal structure of PHB remains almost unchanged until 140℃, but that of P(HB-co-HHx) decreases gradually from fairly low temperature (~50℃).
- 日本学術振興会, 科学研究費助成事業 若手研究(B), 若手研究(B), 関西学院大学, 2006 - 2007放射光を利用した時間分解小角X線散乱による生分解性高分子のラメラ構造形成と熱挙動環境問題や資源枯渇問題から注目を集めている生分解性ポリマーの中でも、微生物が再生可能資源から生合成するポリヒドロキシブタン酸(PHB)は、天然由来の高分子化合物の中でも熱可塑性を有する数少ない生分解性ポリマーであるため、合成高分子材料の代替材料としてだけでなく、医用材料としても期待されている。 本研究ではPHBおよびその共重合体の結晶構造とその熱的挙動について、放射光を用いた時間分解小角X線散乱法(SAXS)および赤外分光法による温度変化測定、X線回折(WAXD)測定、DSC測定法等を組み合わせることにより、官能基レベルから分子全体の構造にわたり温度変化に伴う結晶の格子定数の挙動や、らせん構造の変化、およびらせん分子間に形成され、ラメラ構造の安定化に寄与していると考えられる弱い水素結合(C-H・・・O=C水素結合)の熱的挙動について調べた。特にSAXS・WAXD-DSC同時測定からはラメラの厚みに関する情報や結晶性の情報と熱挙動を同じ系で同時に得ることができるため、非常に有益な情報を得ることができる。それにより、PHBおよびその共重合体の等温結晶化あるいは融解過程における結晶部分とアモルファス部分の厚みの時間変化を詳細に観測することができる。 PHBおよびその共重合体における時間分解SAXS測定の等温結晶化過程の結果から、PHBホモポリマーのラメラ厚は共重合体に比べると厚く、結晶部分の厚みはほぼ初期に決定し、結晶化過程においてはほとんど変化がみられなかった。一方、アモルファス相の厚みは減少し、それに伴いラメラ全体の厚みも減少した。一方、共重合体の場合は、ラメラ厚はホモポリマーと比べると非常に薄いものであった。にもかかわらず結晶化度がそれなりに高いのは、やはりラメラ間をつないでいるC-H・・・O=C水素結合の存在によるものであると考えられる。