The effects of drawing on the various physical properties of acrylic fibers, wet-spun in glycerine and in ethylene glycol, have been investigated. The mechanical properties, density, and X-ray diffraction pattern of these fibers have been measured, together with additionl microscopic observations.(1) The densities of filaments, wet-spun in ethylene glycol bath increase with increasing the draw ratio, and become constant when the draw ratio exceeds 4. On the other hand, the densities of undrawn filaments wet-spun in glycerine bath are larger than those spun in ethylene glycol bath and those of drawn filaments decrease slightly with the draw ratio.(2) The increase of tensile strength and initial modulus with the draw ratio are mainly due to the increase of molecular orientation. The tensile strength and initial modulus of these drawn filaments wet-spun in glycerine bath are larger than those spun in ethylene glycol bath at the same draw ratio. A similar tendency is observed in the change of the degree of orientation with the draw ratio, which was obtained from the X-ray diffraction patterns.(3) The lateral order and the degree of orientation of the filaments are improved by the drawing but in the case of the ethylene glycol bath the latter does not increase in the range of the draw ratio above 6.(4) The microscopic observations show that the cross section of these filaments becomes smaller in size with the drawing but does not change in shape and microscpic fiber texture. The affinity of dyes to these fibers decreases with increasing the draw ratio.

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The effects of irradiation by high speed electrons induced from “Van de Graaff” on the swelling properties of polyacrylonitrile monofilaments were investigated. The results obtained are summerized was follows.(1) The experimental relationship between sol fraction and radiation does shows good agreement with that required by Charlesby's theory. The ratio of degradation to crosslinking occuring byirradiation was about 40%. The crosslinking index per monomer unit was 2.32×10^-5 per 1 Mrad.(2) The swelling properties of the crosslinked polyacrylonitrile have been also studied as a function of crosslinking index. The relationship obtained is roughly consistent with theCharlesby's theory. The deviation of the experimental curve from the theoretical one may be attributed to the uncertainties in molecular weight distribution of the sample and the experimental errors resulting from the use of monofilaments.(3) The values of η_sp/c for sol fractions increase with the degree of irradiation, but decrease after the gel point.(4) Under the presence of oxygen, remarkable main chain fission was observed.

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Carbonyl and hydroxyl groups are formed as a result of dehydrochlorination and oxidation of PVC which is subjected to thermal degradation in the air. Determination of the absolute quantity of combined oxygen is impossible through investigation of infrared absorption alone, so direct microanalysis of oxygen is resorted to. Elementary analysis indicates that removal of one molecule of Cl is accompanied by elimination of about two molecules of H and addition of about 1/2 molecule of oxygen. In the case of 180-°C thermal degradation, 1725cm^-1 infrared absorption and analytical value of oxygen are linearly related with each other, but absorption around 685cm^-1 and analytical value of chlorine are not. Concerning a deteriorated sample, ultraviolet absorption, intrinsic viscosity, solubility to cyclohexanone, specific gravity and Xray diffraction are investigated ; specific gravity increases through thermal degradation, but no change in X-ray diffraction is observed.

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The intensity of X-ray small-angle scattering was measured in order to get a knowledge on the relation between the degrees of crystallinty and swelling of primary gels of the regenerated cellulose fibers which were obtained by coagulation with three different kinds of salt solutions. The diameter of the crystalline cylinder was found to be 53-56Å with the use of Guinier's theory and, as the most probable distance between crystallites, a value of 65-71Å was foud with Kratky's theory. These results were discussed in comparison with the degree of crystallinity and the relation with the degree of swelling was examined.

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The intensity of small-angle scattering of the regenerated cellulose model fibre which was used in the previous report was measured after air-drying. A distinct peak or inflection point appeared on the equatorial line for all materials, which corresponds to a Bragg distance of 60-65Å. The dried samples were again swollen in water and measured. Neither peak nor inflection point was to be observed. Therefore, a caluculation was carried out according to Guinier's theory assuming the crystalline part to be cylindrical and a value 55-60Å was found. The value is greater than that obtained previously for the primary gel under the same assumption.

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Because it is almost impossible to prepare oriented specimens of polyvinylidene chloride, I determined the unit cell dimensions a=6.73Å, b=4.68Å, c=12.54Å, β=56°C25′ and the indices of reflections for polyvinylidene chloride by using Weissenberg photograph of highly-oriented specimens of the copolymer with vinyl chloride which was isomorphous with polyvinylidene chloride. More-over, adequacy for the unit cell of polyvinylidene chloride, was examined by using polyvinylidene bromide which was assumed to isomorphors with polyvinylidene chloride from the infrared spectra.

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Precisely wet-sieved powders of HR or NaR form of Amberlite IR 120 and the same form of Amberlite XE 64, were reacted with a basic dye, methylene blue, in aqueous or alcoholic solution. The following results were obtained; a) The said ion-exchange reactions in the resin phase were observed in spite of the large molecular size of methylene blue. b) Logarism of the amount of absorbed dye is proportional to that of the diameter of resin particle. c) The amount of absorbed dye (E) is in the following relation with the reaction time (t) E=ktⁿ d) The rate of ion-exchange in resin phase is influenced by the apparent density of resin or degree of swelling the order of the rate is HR>NaR in the case of sulfonic acid type resin but NaR>HR in the case of carboxylic acid type resin. e) The rate and amount of ion-exchange in alcoholic solution is markedly small in the case of NaR form of sulfonic acid type resin.

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An analytical study has been made of certain aromatic plasticizers held in a polyvinyl acetate emulsion, for which a polyvinyl alcohol was used as emulsifyer, and the results obtained were as had been expected. The analysis was made by the following method. The qualitative analysis was made by examining the infra-red spectrum of the film formed by the emulsion, as well as by means of a chemical analysis of the solvent extract of the film. The quantitative analysis was made measureing the ultra-violet spectrum of the solution obtained by dissolving the emulsion in an aqueous methanol.

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Several new condensation products of amino benzoic acids (2 mol) and dicarboxilic acid (1 mol) were synthesized. The salts of these products and diamines were heated, and condensation polymers were obtained. Because of containing benzene rings in molecules, these resins have particular structure compared with common polyamides. Especially the condensation polymers were obtained from anthranilic acid, adipic acid and hexamethylenediamine, and the molecular weights of these polymers were estimated by the end group determination method.

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The rates and degrees of r-ray induced polymerization of methyl methacrylate (MMA), vinyl acetate (VAc) and styrene (St) are measured. Dose rates used for MMA and VAc are 0.36×10⁴r/hr to 71.0×10⁴r/hr while for St 0.36×10⁴r/hr to 4.4×10⁴r/hr. The polymerization rates of these monomers are found to be proportional to the square root of radiation intensities at the range of 0.36×10⁴r/hr to 4.4×10⁴r/hr, and slightly decreased above 36.0×10⁴r/hr to 71.0×10⁴r/hr. Linear relations are obtained between degrees of polymerization and does rates in the range of 0.36×10⁴r/hr to 4.4×10⁴r/hr, but at higher intensities it is not in the case, degrees of polymerization decrease to lower values

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The experimental results of γ-ray induced polymerization with various dose rates at 20°C have been reported in previous paper. In this report G values are obtained from k_p/k_t^1/2 for methyl methacrylate (MMA), vinyl acetate (VAc) and styrene (St) from rates and degrees of polymerization, respectively G values are found to be 5.5 in MMA, 1.4 in VAc and 0.04 in St. Monomer transfer constants are also calculated to be 0.36×10^-4 in MMA, 0.80×10^-4 in VAc and 0.08×10^-4 in St, respectively.

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