The state of sorbed water in nylon 6 membranes grafted with acrylic acid (AA) was investigated by differential scanning calorimetry. Two kinds of endothermic peaks were observed for the membranes with comparatively high water content. One was a sharp peak showing the extrapolated onset temperature of melting at 273K. The other was a broad peak whose top temperature of melting was observed below 273K. It was found that there were three kinds of water in the AA grafted nylon 6 membrane: the non-freezing water, the intermediate water, and the free water. The amounts of the non-freezing water and the intermediate water increased with the extent of grafting. It was also found that the AA grafted membrane with high extent of grafting could retain the intermediate water whose state was close to that of the free water.

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The effect of particle size on the rub-fastness has been investigated from the kinetic viewpoint. Hydrated ferric oxide was used as the model of dye because it was rather easy to prepare the several required particle sizes.
The removal amount of hydrated ferric oxide by rubbing increases with increasing particle size and its removal process can be treated as a reversible reaction of first order. The rate constant of transfer of hydrated ferric oxide from adhered fabric to white cloth (k₁), the rate constant of reverse process (k_-1), and equilibrium constant (K=k₁/k_-1) increase with increasing particle size (D) and are proportional to D^0.74, D^0.13 and D^0.61, respectively.

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In the continuous polymerization for acrylonitrile-vinyl acetate copolymer (93:7 in weight) using persulfate-bisulfite ion initiation system in aqueous medium, effects of polymerization condition and fluid mixing on the molecular weight distribution of the polymer have been studied by simulation using a kinetic model with a continuous reactor. The following results were obtained. 1) Few effect of water/monomer ratio and, bisulfite/persulfate molar ratio were observed on _??__w/_??__n ratio of the polymer. 2) When dimensionless parameter _??_L/2_??_ (L, length of a reactor; _??_, mean velocity of fluid; _??_, mean diffusion coefficient toward direction of flow) was varied from 0 to 20, _??_w/_??_n ratio increased from 2 to approximately 4 as a result of increased conversion, depending on the polymerization conditions. 3) The experimental values of _??__w/_??__n ratio can be explained to some extent from the simulation result described.

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Viscose rayon and polynosic fibers were resin-processed by three methods, the pad-dry-cure, the first step of the poly-set, and the full poly-set, in all of which methoxymethylmelamine and dimethylolethyleneurea were used as resins for treatment.
The mechanical and physical properties of the fibers so processed were discussed in relation to the intra-fiber distributions of resins and crosslinks.
It was inferred that the resins showed preferential tendencies, for viscose rayon, of being deposited in intra-fiber voids, while for polynosic, of loosening its tight structure.

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Polycondensation reaction conditions of poly (1, 4-butyleneterephthalate) (PBT) prepolymer obtained by direct esterification of terephthalic acid (TA) with butanediol-1, 4 were investigated. It was found that
1) the amount of tetrahydrofurane formed as a by-product decreases with lowering the conversion of TA at the esterification stage, while the ultimate molecular weight of PBT obtained decreases with lowering the conversion.
2) the optimum reaction temperature is lower than that in the synthesis of other poly (alkylene terephthalates).
3) the catalyst is favorably added at stages of both initial esterification and subsequent polycondensation, although its total concentration does not affect an ultimate molecular weight of the resulting PBT.
To obtain the Mark-Houwink-Sakurada viscosity equation of PBT in o-chlorophenol at 25°C, the samples having the molecular weight in the range from 8, 400 to 67, 000 were prepared and the following viscosity equation was obtained:

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Low temperature plasma treatment is of interest as one of the techniques to modify polymer surface. It has been reported that the treatment offers a good shrink resistance property for wool fabrics. In this study, Merino wool fibers were treated with plasma in oxygen, tetrafluoromethane, and tetramethylsilane. The frictional coefficients of the direction with and against scale, μ₁ and μ₂, respectively, were measured in dry and wet conditions by using a Röder's apparatus. The plasmatreated wool fabrics showed an excellent shrink resistance property similar to the descaled wool fabrics prepared by DCCA and Dylan methods. Electron micrographs of the surface of the plasmamodified wool showed little damage of the scale. It was found that the dry frictional coefficients, μ₁ and μ₂, are increased by the plasma treatment, whereas the value of μ₂-μ₁ is decreased as compared to that of the untreated wool. Both values of wet frictional coefficients and μ₂-μ₁ were greatly increased. The effect of plasma treatment on the frictional coefficients of polyester, nylon 6, and cotton fibers were also studied and discussed on the basis of the surface structure and properties.

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Graft copolymerization of bis (2-chloroethyl) vinylphosphonate (CEVP) with various vinyl monomers initiated with cerium (IV) ammonium nitrate onto cotton fabrics was studied. CEVP alone didn't polymerize in the presence of cellulose and Ce^IVion. Graft copolymers of CEVP-acrylamide (AAm)-vinylidene chloride (VDC), CEVP-AAm-vinyl chloride and CEVP-AAm-vinyl bromide onto cotton fabrics were prepared; AAm and vinyl halides were employed as nitrogen and halogen containing monomers. The cotton satin modified by grafting with these monomers was found to be satisfactory flame-retardant. Charred area and limited oxygen index of the grafted cotton satin consisted of 57.9% CEVP-AAm-VDC copolymeric branch were 30cm² and 32.9, respectively. The grafted cotton satin still conserved the flame-retardant property after 5 times laundry and 5 times drycleaning. Tear strength of the 48.0% CEVP-AAm-VDC grafted cotton satin retained 48% in warp and 56% in weft of those of the untreated fabric. Tensile strength of the grafted cotton satin enhanced to 118% in warp and 109% in weft.

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Aminated poly (vinyl alcohol) (PVA) super fine fibers (SFF) immobilized a lot of baker's yeast, but sulfonated SFF did not immobilize it at all. It was observed by scanning electron microscope that the yeast cells immobilized on SFF proliferated enormously, after it was immersed in glucose solution. The yeast-SFF complex charged into a glass column converted glucose to ethanol continuously.

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