The ¹³C chemical shifts of polyolefins were calculated by the combination of the fraction of the gauche conformation calculated on the basis of the Suter-Flory rotational isomeric state model and the ¹³C NMR γ-gauche effect semi-empirically. The interpretation of ¹³C NMR spectra is difficult by relying only on experimental data, but the chemical shift calculations make the interpretation easier and the peaks related to higher order stereoregularity could be assigned. The origin of the ¹H chemical shift of proteins was also discussed on the basis of semi-empirical chemical shift calculation. The ¹³C chemical shift contour plots were used to determine the structure of Bombyx mori silk fibroin before spinning (Silk I) together with many other structural data obtained from several solid state NMR spectra.

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Poly(L-lactide) (M_n = 1.0 × 10⁵) (PLLA10) films and crystalline PLLA/amorphous poly(DL-lactide) (M_w = 1.0 × 10⁴) (PDLLA1) blend films (PLLA10 PDLLA1) were prepared in a magnetic field and thermal annealing. The small-angle X-ray scattering peak of PLLA10 cast films was at q = 0.24 nm⁻¹. That is, the peak is corresponding to the long-period of the PLLA10 crystals. On the other hand, the SAXS peak of PLLA10 PDLLA1 cast films was at q = 0.33 nm⁻¹. This means that the long-period structure of PLLA10 changed with increasing the volume of amorphous regions in blend films. We thus suggest that such amorphous regions play an important role in preparation of PLLA oriented films in an applied magnetic field.

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In order to use a poly(1-phenyl-2-(trimethylsilyl)acetylene) [PTMSDPA] O₂ enrichment membrane as a cell culture substrate, it was irradiated with an Ar plasma and grafted with poly(N-isopropylacrylamide) [PNiPAAm]. The average amount of grafted PNiPAAm was 1.4 ± 0.7 × 10⁻² mg cm⁻², and the degree of graft PNiPAAm was 29 ± 13. The contact angle (θ) of water at 25°C after treatment decreased from θ = 90° for the untreated PTMSDPA to θ = 48°. HeLa cells attached and proliferated on the grafted polymer (g-PTMSDPA) at 37°C, above the lower critical solution temperature of g-PTMSDPA. After the cultivation of HeLa cells, the thermal stimuli-exfoliation was also examined at 20°C. The ratio of number of thermal stimuli-exfoliation cells to the total number of attached HeLa cells of 3.3 ± 0.3 × 10⁴ cells cm⁻² on g-PTMSDPA was about 28 ± 0.9%, while little thermal stimuli-exfoliation was observed in the case of untreated PTMSDPA. The effect of O₂-supply on cell proliferation was also evaluated by supplying O₂ from the back side of the g-PTMSDPA film at 0.01 MPa, with a flow rate of 20 sccm, for 24 h. The number of HeLa cells and SK-N-SH cells growth under O₂-supply were about 1.4 and 1.3 times higher than that without O₂-supply, respectively.

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A new total internal reflection (TIR) Raman microscope that can be used for adhesion testing based on the Johnson-Kendall-Roberts (JKR) theory was developed. The angle and the focus of the laser beam can be accurately controlled by observing the image of the laser spot on a CCD camera in the spectrometer. As a result, strong Raman signals were obtained. It was observed that the depolarization ratio of polymer brushes changes with the compressive force. This equipment is useful for the analysis of the interface and the anisotropic structure of polymer thin films.

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Novel substituted acetylenes containing benzylideneaniline groups were synthesized, and polymerized with a Rh complex catalyst. The resulting yellow polymers could be obtained in high yield (80~98%). The M_w were in the range of 15×10⁴~37×10⁴ and had an M_w/M_n of 1.8~2.3. The polymers were soluble in common organic solvents such as toluene, chloroform and tetrahydrofuran. ¹H NMR analysis proved that the acetylene triple bonds transformed to polyene double bonds. The polymers showed thermotropic smectic phases as observed by polarizing optical microscopy and Differential Scanning Calorimetry measurements. The polymers were fairly thermally stable, judging from their high onset temperature of weight loss under nitrogen of 360~400°C. The polymers also showed photoisomerization from trans to cis when irradiated by ultraviolet or visible light.

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A Novel linear polyurethane was synthesized by the reaction of 1,6-hexamethylenediisocyanate, Bis(2-hydroxyethyl)terephthalate and castor oil denatured polyol. The polymer was obtained with 51% yield. The molecular weights of the polymer were M_n = 10000, M_w = 16000, by the measurement of gel permeation chromatography. The temperature for 10% weight loss of the polymer was 270°C by thermogravimetric analysis. The stress, strain and Young’s modulus of the polymer was, respectively, 20.19 MPa, 1.43% and 14.11 Mpa by stress-strain curve analysis.

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