Reactivities of amines and reaction regions in aminolysis of PET fibers were investigated by using various primary amines, ammonia, and hydrazine.
Aminolysis occurs randomly and the reaction rate is decreased in the order of MA>HH>EA>n-PA>n-BA>EDA>AM>MEA>iso-BA>sec-BA. There is no correlation between pK_a values of amines and aminolysis rates, however, hydrazinolysis rate of PET fibers is greater than inferred from pK_a value of hydrazine.
Relative phenol adsorption by aminolyzed PET fibers is linearly correlated with the degree of degradation. In giving the above correlation, amines are classified into two groups, i.e. EDA, MEA and MA, EA, AM, HH. Amines in the same group seem to attack similar regions of PET fibers.
Three groups of amines give different alkaline hydrolysis behaviors of aminolyzed PET fibers; group 1 is MA, EA, n-PA, n-BA, group 2 is EDA, MEA and group 3 is AM, HH. Alkaline hydrolysis behaviors of PET fibers degraded by amines in group 1 is as same with untreated PET fibers. Accordingly it may be supposed that aminolysis proceeded uniformly in the fibers. Remarkable weight loss is observed in the early stage of alkaline hydrolysis of PET fibers degraded by amines in group 2, but after that stage the hydrolysis behaviors are similar to that of the group 1. In this case intrinsic viscosity number has increased in the early stage of the hydrolysis. This effect seems to be due to the formation of oligo-esteramides near surfaces of the fibers. Alkaline hydrolysis rates of PET fibers treated by AM and HH increased gradually, as reported in detail in a previous paper. Reactivities of AM and HH are different from other amines, and reactions seem to occur in restricted regions in the fiber.

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Copper filaments were prepared by the glass conjugated melt spinning with changing the winding speed and cooling. Residual stress in the filaments was determined by the X-ray diffraction of the reflecting planes of (400), (222) and (220). The following results were obtained.
1) The residual stress in copper filament obtained by changing the winding speed from 137m/min to 50m/min is compressive and increases with increasing winding speed. The residual stress in the reflecting plane decreased in the following order; (400)>(220)>(222).
The dependency of the residual stress of copper filament is theoretically interpreted by Taira's analysis.
(2) When the copper filament surface is treated by the electro polishing method, the compressive residual stress decreases with polyshing time and a constant compressive stress, which is larger on (220) than others, is found after the polishment for more than 20 seconds.
(3) Large compressive residual stress of copper filament after the cooling treatment was found and was larger on (220) than (222).

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For the purpose of studying the factors involved in evaluating fabric comfort in wear, moisture permeation at non-stationary state in the closed vessel was measured by the dynamic method using an electric hygrometer, and the practical application to the measuring of fabric moisture-permeability was discussed in the light of the obtained results.
1) The diffusion layer of water vapour reaches up to 10mm. hight above the water surface at 20°C in a closed system (82mm. φ, 165cc. volume). The diffusion layer is not disturbed even when a fabric was placed at the diffusion layer fringe.
2) Accordingly, an electric hygrometer was set up within the diffusion layer for satisfactory measurement of moisture-permeability.
3) The measurements on the polyester-ramie fabrics show that the observed decrease in the diffusion rate of water vapour due to the presence of a fabric is linearly related with moisture absorption rate, volume fraction of fiber and air-permeability of fabrics.
4) The dynamic method as applied in the present study turned out to be a rapid and convenient method for determining the fabric moisture-permeability and some important factors related to comfort in wear.

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Chemical constitutions, i.e. N-CH₂OH, N-CH₂OCH₂-N, and N-CH₂-N, of the polycondensation products of dimethylol ethylene urea (DMEU) and dimethylol propylene urea (DMPU) prepared under the various curing conditions were studied. N-CH₂OH and free CH₂O in the reaction products were determined separately by the application of the KCN method. Contents of N-CH₂OCH₂-N and N-CH₂-N were determined separately from the difference of their hydrolysis rates to acetic acid, and confirmed by the NMR method. The kinetics in these hydrolyses were also studied.
Chemical constitutions of the polycondensation products were affected remarkably by their curing time and temperature. With changing the curing time at 120°C, N-CH₂OCH₂-N was formed rapidly at first, and then decreased with time, while contents of N-CH₂-N and free CH₂O increased at about the same rate with time. It was suggested that the N-CH₂OH in DMPU or DMEU was rapidly consumed for the formation of N-CH₂OCH₂-N, which decomposed gradually into N-CH₂-N and free CH₂O in the polycondensation. The similar tendencies for the formation of N-CH₂OCH₂-N, N-CH₂-N and free CH₂O were also found with changing the curing temperature for 30min. Degrees of polycondensation of DMPU and DMEU oligomers, in both cases, reached 9-10 in maximum. It was also found that Zn(NO₃)₂ showed excellent catalytic action leading to the formation of N-CH₂-N in considerable amounts, but MgCl₂ only affected the formation of N-CH₂OCH₂-N, and Mg(CH₃COO)₂ had almost no catalytic action under a curing condition, 120°C, 30min.

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A detailed uv-spectral investigation on the interaction of Direct Sky Blue 6B (C, I. Direct Blue 1) with a cationic polyelectrolyte (methyl-hydroxyethyl-diallylammonium chloride-SO₂ copolymer) in dilute aqueous solution has been carried out.
Under appropriate conditions the binding of the dye to the polycation gives rise to a marked change in its spectrum.
When approximately equivalent polycation and dye are present in the solution, the so-called stacking spectrum due to polymolecular adsorption of the dye to the polymer is found. When polycation concentration exceeds largely, the so-called binding spectrum due to monomolecular adsorption of the dye is observed. Complex formation on the polymer between Sky Blue 6B and Chrysophenine G was found.
The effects of urea, caustic soda and sodium chloride on the spectrum of Sky Blue in the presence of the polymer are also discussed.

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In the previous study it was shown that poly (ethylene terephthalate) (PET) fiber treated with highly concentrated sulfuric acid had good dyeing properties for cationic dyes under normal pressure. Better results were obtained in the present study by treating PET fiber with sulfuric acid of higher concentration;
Sulfation carried out with sulfuric acid of 78% at 80°C for 40min., further improved the dyeing properties and tensile strength of the fiber. Diffusion coefficient of Malachite Green in sulfated PET fiber were also measured. Activation energy of diffusion was calculated and was compared with polyacrylonitrile fiber case.

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In order to dye polyurethane synthetic leather with acid or substantive dyes, basic amino-groups were introduced on the polymer prepared by wet process by means of three methods; (1) graft reaction to the unsaturated groups which were preintroduced on nitrogen of the polyurethane by anionic reaction, (2) preparation of the polyurethane by using nitrogen containing chain extending reagents, and (3) radical graft reaction of nitrogen. containing monomers onto the polyurethane. The best result was obtained by the third method in which N-vinylpyrrolidone (NVP) was reacted in DMF with the polyurethane using AIBN. Since no solvent for fractionation was found, the graft percentage was not determined, but was assumed small. The grafting copolymerizations of NVP with vinyl monomers insoluble in water were also carried out to prevent the dissolution of the grafted polymer. 2-Diethylaminoethyl methacrylate (DEM) gave a good result for dyeing degree and homogeneity. Blending of the polyurethane and copolymer of NVP and DEM did not lead to homogeneous dyeing. These polymers were found to be incompatible as judged from the dynamic viscosity of the mixed polymer solution.

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