Structural Changes in cotton fabrics and Tencel fabrics treated with sodiumu hydroxide aqueous solution or liquid ammonia wer evaluated by spin-lattice relaxation behavior (T_1C) in CP/MAS ¹³C NMR spectroscopy. Distribution of T_1C for cotton was shifted to the shorter range of time by these treatments, which means the mobility of molecular chains increased. As the both treatments induced crystalline transition without remarkable change in the degree of crystallinity, coexistence of different crystalline phases may be related to this phenomenon. Similar tendency in T_1C distribution was observed for Tencel treated with liquid ammonia, in whitch crystalline transition also occurred. On the other hand, distribution of T_1C for Tencel treated with sodium hydroxide shifted to the longer range of time. As no crystalline transition was induced in this system, increase in the crystallite size may be one of the reasons to decrease the molecular mobility of the crystalline region.

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We observed Raman spectra of Silk I and Silk II powders of (Ala-Gly)₁₅, which is a model peptide of crystalline region of Bombyx mori silk fibroin. Additionally Raman spectra of Ac-(Gly-Ala)₄-NHMe and Ac-(Gly-Ala)₃-NHMe with Silk I and Silk II forms were calculated according to the repeated β-turn type II structural model and β-sheet model, respectively. The ab initio molecular orbital calculation was used for the theoretical calculation. The calculated results could reproduce the spectra. Especially, in silk I form, observation of splitting of amide I and III bands was in agreement with the predicted bands according to the repeated β-turn type II structural model.

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Micro-pore structures of swollen cellulosic fibers were discussed on the results obtained by the size exclusion chromatography operated at different temperatures. In order to compare all chromatographic results obtained at different running conditions, we introduced a new capacity factor. Different swelling behaviors were observed among the cellulosic fibers. The swelling volumes of cellulosic yarns were also determined respectively at 30°C and 60°C.

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The fine particles in the emulsion particles of tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer [PFA] and poly(vinylidene fluoride) [PVDF] were examined by transmission electron microscopy. Fine particles jumped out of the surface regions of PFA emulsion particle by annealing for 4 minutes at 270°C. This phenomenon suggests that the molecular weight of fine particles located at the surface regions of PFA emulsion particle is lower than that of fine particles at the inner part of the emulsion particle. Such a result is also the case for the PVDF emulsion particle. The molecular weight distribution in a PVDF emulsion particle is assumed to be reflected as the molecular weight of individual fine particles constituting the emulsion particle.

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Polarized Raman spectra for the various types of poly(ethylene terephthalate) fibers were measured using microprobe spectroscopy changing the optical systems, and the conditions suitable for the estimation of density and molecular orientation of the fibers were discussed. For the estimation of density, the full width at a half maximum of 1730 cm^-1 band measured under the laser polarization direction parallel to and Raman polarization direction perpendicular to the fiber axis was most convenient. For the estimation of molecular orientation, the parameter using the ratio of relative Raman intensities, that is (I₁₆₁₅ / I₆₃₂)/(I₁₆₁₅ / I₁₇₃₀) which showed the highest correlation coefficient against birefringence, was suitable: Here, I₁₇₃₀, I₁₆₁₅ and I₆₃₂ are the intensity of 1730cm^-1, 1615cm^-1 and 632cm^-1 bands, respectively. The relative intensity, I₁₆₁₅ / I₆₃₂, was measured under both laser polarization and Raman polarization in the direction parallel to the fiber axis, and I₁₆₁₅ / I₁₇₃₀ was measured under both laser polarization and Raman polarization in the direction perpendicular to the fiber axis.

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