Solutions of hydroxypropyl cellulose (HPC) in N. N-dimethylacetamide (DMAc) form cholesteric liquid crystal above a certain critical concentration. Two kinds of HPC films were cast from the isotropic concentrated solution at different temperatures (-18 and room temperature); HPC film cast at -18°C (HPC-A) appears to remain the cholesteric order in the liquid crystalline solution relatively well than HPC-B (cast at room temperature). The creep behavior of those solid HPC films was determined in vacuo as a function of stress or temperature and was analyzed on the basis of Eyring's activated process. The effect of the casting condition on the creep behavior and Eyring's activation parameters (activation volume V and activation energy ΔU) was discussed. HPC-A exhibited less creep strain than HPC-B. Eyring's activated process could be applied to the creep behavior of HPC films. V of HPC-A was smaller than that of HPC-B. V increased with temperature. V appeared to be smaller than the apparent volume of liquid crystalline domain. ΔU for HPC-A was smaller than that for HPC-B. Further study requires to fully clarify those creep behavior of cellulosic liquid crystalline films.

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The crystal structure of poly (p-benzamide) was determined by the X-ray diffraction method. All reflections were indexed by an orthorhombic unit cell with dimensions of a=7.74(2), b=5.27(1), and c=12.82(5)Å The space group symmetry was P2₁2₁2₁. The unit cell contains two 2₁-helix polymer chains. The detailed structure was analyzed by the linked-atom least-squares method. It was found that the crystal structure was composed of stacked sheets in which polymer chains link to each other by NH-0 hydrogen bonds along the b-axis. No hydrogen bonds form between these sheets. This scheme of the hydrogen bonding is quite similar to that in poly (p-phenylene terephthalamide). As observed in other aromatic amide compounds, torsion angles between the amide and the benzene plane are about ±30°.

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The heterogeneous addition reaction of the silk fibroin fibers of Philosamia cynthia ricini with various monoepoxides was investigated in ethanol and cyclohexane at 45-75°C after the fibers were padded with aqueous solutions of various salts as catalysts. The reactivity of the main functional amino acid residues was found to decrease in the order: histidine _??_ tyrosine _??_ arginine. The concentration of the aqueous salt solutions influenced the reactions of tyrosine and arginine, but did not affect largely those of histidine and lysine. The reaction rate of tyrosine was discussed in terms of the nucleophilicity of the anions of the catalyst. The reactions of tyrosine and histidine depended on both of the polar and steric factors of the substituents of the epoxides. Their effect was elucidated by the modified Taft equation. The reactivity difference of tyrosine, arginine, and histidine between Philosamia cynthia ricini and Bombyx mori silk fibroins towards the epoxide was partly explained with swellability and intermicellar distance of the fibroin fibers and the amino acid composition of the fibers.

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The effect of polyelectrolytes on the transport of various sulfonated direct dyes, C. I. Direct Yellow 12, C. I. Direct Red 2 and C. I. Direct Blue 15 from aqueous solution into a cellulose membrane has been studied at 25°C and 55°C. The diffusion of the dyes into the cellulose membrane was analysed on the basis of a parallel transport mechanism of surface and pore diffusion as developed in our previous paper. The nature and concentration of the polyelectrolytes influenced the adsorption equilibrium but had no effect on the diffusion coefficient of the dye. The diffusion coefficients of the dye obtained in the presence of the polyelectrolyte agree with those obtained in the presence of small inorganic electrolytes.

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The hydrolysis of two vinylsulfonyl reactive dyes, C. I. Reactive Orange 7 and Red 22 was investigated at 50°C. The rate constants of hydrolysis from the sulfatoethylsulfonyl (SES) type to the vinylsulfonyl (VS) type and those from the VS type to the hydroxyethylsulfonyl type were estimated. The former rate constants were about 5000 times larger than the latter ones. It was confirmed for both the dyes that no dimer of the bis (arylsulfonylethyl) ether type was formed under the conditions examined.

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