A novel process for the formation of poly (p-phenylene terephthalamide) (PPTA) film from liquid crystalline sulphuric acid solution was developed. A homogeneous and transparent PPTA film is very difficult to obtain from sulphuric acid solution owing to the highly anisotropic flow properties of the solution. A biaxially balanced PPTA film could be formed by using the optically anisotropic to isotropic transition appeared in the phase diagram of the PPTA sulphuric acid solution. The phase transition was generated by controlling temperature and/or polymer concentration of the solution. The anisotropic solution was cast on a flat glass plate. The cast dope was carried into a conditioning chamber (air oven) in which the phase transition occurred before it was immersed into the coagulation bath. The isotropic cast dope was coagulated and dried holding dimensions constant. The adjustment of temperature and water content of the cast dope plays an important role in the process and directly affects the properties of the film obtained. The conditioning at 100°C was suitable for the film properties in a series of experiments. The Young's modulus of 14 GPa and tensile strength of 450 MPa were obtained for the film heat-treated at 350°C during 20min. This process can be applied to a continuous large scale process.

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The contact resistance behaviors of the fabrics during the water transmission process were investigated by measuring: (1) the contact resistance between the fabric settled on a metal cylinder, to which a fixed amount of water was supplied, and the sample fabrics during the water transmission process, (2) the contact resistance between the metal cylinder and the wet sample fabrics during the drying process, and (3) the stress acting on the wet fabrics during the drying process at a fixed strain under about 1.5%. The contact resistance showed a minimum, and increased during the falling rate period of drying, ranging approximately between 0.1g/cm² and 1g/cm². These changes were more remarkable with hydrophilic fabrics, particuraly with silk, than with hydrophobic fabrics. The wet fabric stress increased during the falling rate period, apparently due to contraction force. The relationship between the capillary adhesion force and the geometrical amount of water was calculated by using the derived plane model. The capillary adhesion force increased with decreasing geometrical amount of water. The dependence of the capillary adhesion force, the stress and the frictional coefficient on the contact resistance were also estimated by introducing the stress factor to the derived equation. The experimental results could be qualitatively interpreted in terms of the above mentioned equation.

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Poly (ethylene terephthalate) (PET) and nylon 6 films stretched uniaxially and biaxially were treated with sputter etching in the presence of argon gas. Surface of the treated films was examined by scanning electron microscopy [SEM]. While cracks perpendicular to the stretching direction were observed with the uniaxially stretched films treated for 30minutes, many protrusions were formed in the biaxially stretched films at height of 0.3-0.4μm for PET and 0.1-0.2μm for nylon 6. One protrusion was made up to the top of two or three protrusions with increase in the treatment time to 60minutes. Contact angles to water of the sputter etched PET and nylon 6 films were remarkable decreased by the treatment for 1-3minutes. The accampanying chemical changes were analyzed by ESCA. In both films treated with sputter etching, the C_1S intensity decreased and the O_1S intensity increased in comparison with the untreated films.

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Molecular characterization of polystyrene grafted onto nylon 6 fiber by a γ-ray pre-irradiation technique in air was performed. The molecular weight and molecular weight distribution were determined by measuring limiting viscosity number |η| in m-cresol of fractions of the grafted polystyrene obtained from the nylon 6-styrene graft polymer as well as of the homopolystyrene produced in the nylon 6-styrene system. The molecular weight distribution of the grafted polystyrene was rather broad compared with that of the homopolystyrene produced by the γ-ray pre-iradiation method under the same experimental conditions. Partial occurrence of H-type grafting (the propagation of a grafted chain is terminated by the reaction with another propagating grafted chain.) of polystyrene onto nylon 6 fiber was suggested in the latter period of the nylon 6-styrene system, while T-type grafting (the propagation of a grafted chain is terminated by the reaction with propagation chain of homopolymer) predominated in the nylon 6-styrene/toluene system.

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Styrene was grafted onto nylon 6 fiber by the γ-ray pre-irradiation technique in air. The effect of chain transfer agents such as toluene, triphenyl methane, cyclohexanone, and carbon tetrachloride on the molecular weight and the number of the grafted polystyrene was investigated. The molecular weight (M_n) of the grafted polystyrene was determined by the limiting viscosity number |η| measurement after selective hydrolysis of the backbone. The molecular weight of the grafted polystyrene decreased by adding chain transfer agents such as toluene, triphenymethane, cyclohexane, and carbon tetrachloride into the medium, while the number of grafted polystyrene was not effected by these agents, in most cases. On the other hand, the number of grafted polystyrene increased by adding water or methanol into the medium. In these cases, the molecular weight of the grafted polystyrene was not affected by water or methanol.

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Vinyl monomers, such as styrene, methyl methacrylate, methyl acrylate, vinyl acetate, acrylonitrile, and acrylamide, were grafted onto nylon 6 fibers by a simultaneous γ-ray irradiation technique. The effects of various additives on the apparent percent graft as well as on the molecular weight and mole number of grafted vinyl polymer branches were investigated. The molecular weight of the grafted vinyl polymer branch was determined by the limiting viscosity number of the branch polymer obtained by selective hydrolysis of the backbone nylon 6. The apparent percent graft of the grafted polystyrene increased by adding methanol, ethanol, acetic acid, or propionic acid to styrene monomer. The maximum amount of the apparent graft was obtained at the 1:1 mixture of styrene and methanol. The additive which behaved as a good swelling agent to nylon 6 and, at the same time, as a precipitant to polystyrene gave higher apparent percent graft. The apparent percent graft of vinyl monomers except vinyl acetate was increased by adding methanol or ethanol to the monomers.

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Swelling of silk and rayon fabrics by organic solvents depended on the kind and the temperature of the solvents and the period of immersion. The degree of swelling after the shrink proofing using phosphoryl amide was comparable to that before the proofing. Dimethyl sulfoxide was one of the best solvents for the shrink proofing by phosphoric amides. Some of the fundamentals govering the shrinkage of silk goods were explained on the basis of the release of the strains imposed during manufacturing processes, and the swelling produced on wetting. The mechanism of the swelling by organic solvents was explained in terms of the solubility parameter of the solvents and hydrogen bonding and dipolar interactions between silk and the solvents. The most important factor for the shrink-proofing would be cross-linking between the fibers in the very vicinity under the swelling, up to 100%, of the fabric by covalent bonding and/or adhesives.

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The fabrication of sodium alginate fiber was performed by spinning in a hydrophilic organic solvent as the coagulation media. The fiber obtained by this procedure was water soluble. In case of acetone, the fiber obtained showed tenacity up to 1.1 gf/denier, which was the highest strength among the various solvent systems. The tenacity of the fiber was decreased with rise in spinning temperature and with increasing water content of the solvent. Sodium was the most favorable counter ion of the alginate for fiber fabrication from the point of tenacity. The application of the sodium alginate fiber for antibiotic carrier was investigated. Antibiotics such as polymyxin B sulfate or tetracycline hydrochloride was admixed into the alginate solution and was spinned to yield the antibiotic entrapped fiber for potential applications.

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The Michael type addition reaction of ethylene/vinyl alcohol copolymer (EVAL) with a series of alkyl vinyl sulfones, namely methyl, ethyl and t-butyl vinyl sulfone, was performed with NaOH as a catalyst in dimethyl sulfoxide solution to produce corresponding 2-(alkylsulfonyl) ethyl EVAL derivatives. The degree of sulfonylation of hydroxyl groups in EVAL exceeded 90% in the reaction with methyl and ethyl vinyl sulfones, while remained at most around 65% with t-butyl vinyl sulfone.

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