Segmented poly-urethaneureas (PUUs) are commercially known as high elastic polymeric material. Those PUUs composed of hard and soft-segments are known to form aggregations in organic solvents. Although molecular characteristics of PUUs in organic solvents have been studied in detail, the study on aggregative properties have not been reported so far. In this study, the aggregation process in concentrated PUU/N, N-dimethylacetamide (DMAc) solution system was studied using static light scattering technique (SLS). A set of dust-free concentrated PUU/DMAc solutions were carefully prepared then heat treated at various temperatures. SLS measurements on the diluted solutions prepared from those concentrated solutions with filtrated DMAc resulted that z-average radius of gyration <S²>_z^1/2 and M_w increased by the heat treatment of those concentrated solutions. This phenomenon can be understood by the aggregation of PUU molecules in this system.

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The dope, which consisted of Acrylonitrile (AN)-Methylacrylate (MA) copolymer (AN/MA=90/10wt%, Mw=15.9×10⁴) dissolved in 58wt% aqueous NaSCN, was casted into film and coagulated with a dilute aqueous NaSCN solution. Diffusion of solvent (NaSCN) was measured under various coagulation conditions. During coagulation the diffusion coefficient D of NaSCN in proto film increased with the coagulation temperature but decreased with the NaSCN concentration of coagulant and polymer concentration of the dope. The coagulation became fast with the increase of diffusion of solvent and concomitantly the microstructure of gel became rough. The apparent activation energy was 5.2kcal/mol. Using the diffusion coefficient obtained above, the time necessary to complete the coagulation throughout wet spun fiber was estimated, which gave satisfactory coincidence with observation of fiber obtained by the two stepwise wet spinning process.

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The permeability to fluids and the surface strength of paper can be controlled by the addition of internal and surface sizing agents. The amount of the sizing agents precipitated onto pulp fiber has been analysed mainly by colorimetry or pyrolysis-gas chromatography. In this study, ESCA technique is newly proposed to determine the sizing agents content in the paper. The carboxyl and the hydroxyl groups in these agents were labelled with fluorine atom by the gas phase chemical modification technique, and then the fluorine atom was monitored by the ESCA. As a result, there was a correlation between the amount of fluorine and the amount of surface sizing agents (PVA: polyvinyl alcohol) or internal sizing agents (rosin). And PVA contents on the surface of paper was determined by the calibration curve of PVA contents. Further it was found that there was a correlation between rosin contents obtained by ESCA and rosin contents obtained by pyrolysis-gas chromatography.

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The influence of optical properties on the tinctorial depth of dyed polyester fabrics consisting of single fibers of different deniers and different cross-sectional shapes was investigated. Dyes were applied over a wide concentration range, using three disperse dyes of different hue. To assess the optical properties of the dyed fabrics, light-scattering and light-absorption coefficients were obtained using the Kubelka-Munk and Minato methods, respectively. New Shingosen fabric, woven with especially fine microfibers, had a higher light-scattering coefficient than fabrics made from conventional fibers, regardless of the uptake or hue of the dyes used. This was ascribed to the increased surface area of the Shingosen fabric changing both the surface reflectivity and light-scattering properties. The higher light scattering coefficient led to a lower K/S value. The latter value was correlated with perceived depth, and consequently, the perceived depth of the Shingosen fabric tended to be weak.

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Novel cellulose filaments from aqueous caustic soda solution were spun by sulfuric acid coagulation method on bench scale. In this spinning, the concentration of sulfuric acid was found to seriously affect on the structure and tensile properties of the yarn obtained. When draft ratio is constant, both degree of orientation and packing density which are measured as the degree of swelling of never dried yarn increase with an increase of the sulfuric acid concentration and the time of coagulation. It was inferred that dehydration effect of the sulfuric acid markedly increases with an increase of its concentration. The dehydration of the sulfuric acid gives rise to high shrinking stress in the coagulating yarn, leading to high orientation and packing density. Consequently, the yarn obtained showed high tensile strength and high initial Young's modulus. The shrinking stress due to the dehydration effect was calculated and it was found that the stress drastically increases when sulfuric acid concentration was 40-50wt%. Based on these facts, cellulose filament with tensile strength in dry state higher than that of regular viscose rayon was successfully obtained using sulfuric acid with concentration of 50-65wt%.

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In wet spinning of cellulose filament, a new coagulation method (net process) which can suppress tension on the filament at low level was successfully devised. An employment of this method for the spinning of new cellulose filament from caustic soda solution made it possible to spin at up to 200 m/min. This process includes a cylindrical shaped spinning funnel used for the viscose rayon and a net, as a supporter of coagulating filament, which runs as the same speed of winding roller. Using this method, we can principally spin the filament at any high speed, because of less hydraulic resistance arising from coagulant, Important factors to obtain high spinning speed and good mechanical properties of as-spun cellulose filament were found to be as follows: (1) Lowering draft ratio by an increase of extrusion speed at spinnerets; (2) reducing the hydraulic resistance at early stage of coagulation by shortening the distance from spinnerets to inlet of the funnel; (3) reducing the hydraulic resistance in the funnel by minimizing the velocity difference between coagulant flow and take-up speed of the filament; (4) drawing the never dried filament by 1.2-1.3 after coagulation. Using the spinning apparatus designed to satisfy these conditions, we obtained the cellulose filament with comparable mechanical properties to commercially available viscose filament at the same spinning speed as that of the viscose (100 m/min).

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Linen fabrics are popular as materials for spring and summer suits because of the cool feeling. However, the fabrics are easily wrinkled. In addition, the feeling of touch is hard and the dyeing properties are not so good. Various procedures have been investigated to overcome these demerits. In the present work, low temperature plasma of oxgen was applied to the fabrics to improve the properties. Moisture absorption, wrinkle proof, etc. were investigated. Linen fabrics became light and soft. Ability of spring back of fabrics increased and the wrinkle proof became better. The diffusion/absorption rate increased. The properties were related to the surface phenomena observed by ESCA and SEM; i.e., the content of oxygen increased and the small voids appeared with the increase of plasma treatment time.

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