The electrokinetic properties of polyvinyl alcohol fibers in water and in solutions of several electrolytes have been studied using the streaming-potential method. The surface charge density was calculated from the following equation:
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The results showed that the charge density was related to the dissociation of carboxyl groups in fiber and to the adsorption of anions from the solutions. The relationship between the surface, charge density and the degree of swelling of these fibers was also discussed.

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The ζ-potential of polyvinyl alcohol fibers partially acetalized with azelaic acid monoaldehyde was determined in aqueous solutions of sodium hydroxide or hydrochloric acid. It was found that the potential of acetalized fibers was less affected by the concentration of the alkali medium than that of the standard polyvinyl alcohol fiber. This may be due to the increasing swelling and counter-ion binding of the amorphous part with the increasing degree of neutralization of acid groups involved.

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The relaxation time spectrum of the so-called Rouse chain is investigated from the viewpoint of thermodynamics of relaxation phenomena, and the connection of the shape of the spectrum to the distribution of normal modes in the chain is indicated. If we assume that then intersubmolecular elastic force is anisotropic owing to the presence of crystalline regions, then we can show that under some suitable conditions the spectrum has for the large relaxation time a nearly flat shape, which is in accordance with that of crystalline polymers, where the more-than-one dimensional distribution of normal modes in the chain plays a role in the relaxation mechanism. That careful use of Ferry's reduction rule is still valid for crystalline polymers is explained.

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The purpose of this paper is to make clear the cause of “Wet Cracking” which occurs when the polyvinyl formal film stretched and held at constant strain comes in contact with common liquid. The relation between the temperature (T°K) at which coating film is treated in air and the duration (λhr) necessary to make the latent crack disappear, is experimentally found to be λ=Aexp (U/RT). On the other hand, it is discovered by means of volume dilatometer that the heat-treated temperature is equal to the second order transition point of the coating film in the ordinary observational timescale. Finally, its cause is discussed in view of stress relaxation in film held at constant deformation.

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The intrinsic viscosity, [η], of Polyvinylalcohol (PVA) fraction were measured at 30°C in dimethylsulfoxide (DSO). The results can be correlated by an equation, [η]=3.79×10^-4P^0.84 This suggests that DSO is much better solvent than water for PVA. Then dimethylsulfoxide (DSO). The results can be correlated by an equation, and swelling degree of unfractionated PVA were measured in mixed solvent such as water-DSO, waterphenol and water-ethyleneglycol. The results lead to following conclusions.(1) Mixed solvent at 40-70 vol % of DSO is poor solvent for PVA.(2) In water-ethyleneglycol system, solvent is inclined to be poor with addition of ethyleneglycol.(3) In water-phenol system, 2%; aqueous solution has maximum solvent power.(4) In all systems, increase of dimethylsulfoxide (DSO). The results can be correlated by an equation, and accompanied decrease of k′, perhaps due to polymer association, were observed near the precipitation point. This supports the theory that is k′=0 at precipitation point.

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The intrinsic viscosity, [η], of polyvinyl acetate (PVAc) fraction were measured at 30°C in dimethylsulfoxide (DSO). The results can be correlated by an equation, [η]=6.87×10^-4 P^0.63 This suggests that DSO is equivalent to aceton as solvent for PVAc. Then [η] of PVA-PVAc mixture, partially acetylated PVA and partially saponified PVAc in DSO were measured. In PVA-PVAc-DSO system, additive property of [η], [η]_mix.=[η]_A^wA+[η]_Ac^w_Ac, does not hold in the range of w_A>0.6. Besides the range of small acetyl %, [η] of saponified PVAc is larger than acetylated PVA at equal acetyl %. Based on these experimental results, the effects of distribution of acetyl group (or hydroxy group) on [η] were discussed.

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Two cellulose acetates, a triacetate (acetic acid yield 60.5) and a secondary acetate (acetic acid yield 54.5%) have been studied by osmotic pressure, viscosity and dilution ratio (volumes of hexane required to cause initial phase separation from solution) methods in various compositions of mixed solvents, methylene chloride-methanol and methylene chloride-acetone. The solvent power of methylene chloride-methanol mixtures shows a maximum at 85%(by volume) of methylene chloride for the triacetate and at 65%, for the secondary acetate, which is indicated by the parallel behavior of [η], k′(minimum) and dilution ratio. Combining the thermodynamic conditions for the compositions of the mixed solvent at the maximum in its solvent power and at the critical miscibility point with the osmotic data on triacetate-methylene chloride system, the interaction parameter can be computed for each pair of the components in the ternary system. The parameters thus obtained seem capable of accounting, in a satisfactory manner, the relationship between the measured quantities ([η], k′, and dilution ratio) and the composition of the mixed solvent. In the triacetate-methylene chloride-acetone system, however, the final state of the solution differs according to the method of its preparation. Some of the factors affecting the intrinsic viscosities of dilute solutions of the two acetates are discussed in terms of the “long range interference”and “short range interference” in the polymer chains, including their dependency upon temperature.

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The nylon 6 filaments stretched on the occasion of melt spinning process give the x-ray photographs (A-structure) which obviously differ from those of the ordinary nylon 6 filaments. And the similar x-ray photographs (B-structure) are obtained when the nylon 6 filaments are treated with iodine-pottassium iodide solution. These x-ray photographs show the stronger meridional (020) spot than that of the ordinary nylon 6 filaments and one strong equatorial spot instead of the two strong spots (A₁, A₂) of the ordinary nylon 6 filaments. The former (A-structure) is the unstable form and is transformed almost completely into the ordinary nylon 6 crystalline form by annealing, but the latter (B-structure) is the very stable one and does not change until it melts. The infra-red absorption spectra of these types (A-and Bstructure) of nylon 6 filaments demonstrate that the former has not hydrogen bond while the latter persist it completely. Several proposal crystal structures of these nylon 6 are suggested and their validities are examined.

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In order to clarify the mechanism of “cold drawing”, tensile tests under various conditions were carried out on several textile materials, such as nylon 6, polyacrylonitrile and regenerated cellulose fibers. On the basis of these results, the general mechanism of “cold drawing” was discussed. The so-called necking phenomenon is only observed under suitable conditions for “cold drawing”, and is mainly due to the local generation of heat on the drawing process. The suitable conditions mentioned above vary with the nature of the internal structures of fiber, and seem to be related closely to the elastic dispersion in glass transition region.

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Fractionated polyvinyl alcohols (PVA) with various DP were randomly formalized to different extents (13, 15.5 and 19 mol%). Aqueous solutions of these samples were prepared, and the relation between the temperature of phase separation and the concentration of the solution was experimentaly determined. It was observed in all these cases that the solution had a critical temperature T_c, under which phase separation did not occur. The higher was DP or the substitution degree, the lower was T_c. Similar results were obtained for aqueous solutions of selectively acetylated PVA. From the relation between T_c and DP thermodynamic constants were calculated according to the Flory's theory, and these constants were compared for various partially substituted PVA.

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(1) The modified osmometers of Fuoss-Mead and Zimm-Meyerson types were illustrated.(2) The agreement was satisfactry between the experimental results with two different types of osmometers on two samples of fractionated polystyrene in toluene and methyl ethyl ketone.(3) On the partially permeated sample of polystyrene, the effect of permeation was more remarkable, and the apparent value of M_n evaluated appeared to be a little larger with Fuoss-Mead's osmometer than with Zimm-Meyerson's one.

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As single yarn in bent fabric was changed the twisted angle by bending, the local stresses on a fiber were analyzed by the relation between the stresses on a fiber in bending plane when the twisted angle was not changed and the local twisted angle. Then this paper was calculated numerically for a exl.rnple of acetate yarn. As the results, there was little difference between the stresses on a fiber in bending plane when the twisted angle was not changed by bending and local stresses in bending plane when the twisted angle was changed.

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The polyurethanes having terephthaloyl groups have been prepared by the polyaddition reaction with bis (hydroxy-polyoxyethylene) terephthalates and diisocyanates. These linear polyurethanes have rubberlike elastic properties by the effects of terephthaloyl groups and urethane linkages which are arranged regularly in the polymer chaines. For an example, 1 mole of bis (hydroxy-tetraoxyethylene) terephthalate and 1.15 mole of 2, 4-toluylene diisocyanate are heated together at 100°C for 6 hours to give polyurethane with an intrinsic viscosity in m-cresol at 25°C of 0.24. The product melts at 170-177°C and a molded sheet of this polyurethane has a tensile strength of 96.7 kg/cm² and elongation of 330%.

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A simple method for the determination of vinylchloide monomer was studied. Vinylchloride was oxidized in the KMn O ₄-H ₂ SO ₄ solution of a certain concentration, in order to prevent generation of chlorine or hypochlorous acid and such like. And the produced chlorine ion was titrated with Ag NO ₃ solution.

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The ester interchange reaction between polyethylene isophthalate and ethylene glycol was studied kinetically. It was observed that the reaction occurs randomly between free hydroxyl group and ester linkage of the polyester, independent to it's chain length. Bimolecular rate constant increases linearly with the increase of the concentration of ethylene glycolate as a catalyst. Energies of activation were observed as 32 kcal/mol for noncatalytic interchange and 19 kcal/mol for catalytic case. We discussed the mechanism of this reaction and concluded that complex formation from ester linkage and alcoholate may be the rate determining step.

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It is known that polyvinyl alcohol is precipitated from its aqueous solution with congo red, a substantive dye, as with boric acid. According to our experiments, in 1.5% congo red solution gelatination occurs while in 3% solution syneresis takes place. Changes in X-ray diagrams also begin to be remarkable from this concentration. The most strong interference corresponds to a spacing of 4.21Å. By the immersion of polyvinyl alcohol films or filaments in congo red solutions of various concentrations, similar results are obtained. After the immersion, the films and the filaments are plastic and can be drawn to several times of their initial length. X-ray diagrams of such drawn filaments show three new interferences on the meridian. The specings are 13.20, 8.80 and 6.54Å respectively. The fiber period calculated from the above spacings is 26.4Å. While such interferences can be found neither by pure polyvinyl alcohol nor by congo red powder, it may be assumed that these interferences belong to a complex between polyvinyl alcohol and congo red. A provisional estimation of the monoclinic unit cell of the complex is as follows:α=8.20Å, b=26.4Å, c=4.57Å, β=81°30′.

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Copolymers of vinyl acetate (A) and methyl methacrylate (B) with various composition were prepared, and saponified under the condition that poly A was completely but poly B was. scarcely saponified. Even under such a codition some part of B in copolymers was saponified. As a result of comparison of observed saponification degree with theoretical values for various. saponification mechanisms, the following conclusion was deduced. Each A in a copolymer molecule accelerates saponification of B which is a next-door neighbour to it. Saponificatiork mechanism of copolymers of methacrylic acid and methacrylic amide was also discussed.

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Saponified products of copolymers of vinyl acetate (A) and methyl methacrylate (B) on which had been reported previously were acetalized with chloroacetaldehyde. Prior to acetalization OH groups produced by saponification of A formed lactone with next-door neighbour COOH groups produced by the saponification of B. Observed acetalization degree was compared with theoretical values for various saponification mechanisms of B. Consequently a conclusion was deduced that each A in the copolymer molecule accelerated saponification of B which isa next-door neighbour to it. This conclusion agrees with that of the previous report.

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Carbon tetrabromide is found to accelerate the rate of γ-ray polymerization of styrene. In this case, the degrees of polymerization are much smaller than those expected by the theory previously reported. In this solution polymerization by γ-irradiation, a new kinetic scheme is proposed here. According to the calculation scheme of Chapiro, the G-value of radical formation of carbon tetrabromide in styrene is recognized to be about 8, 500.

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Acetic acid, water and uranyl acetate are found to accelerate the rates of the radiation polymerization of vinyl acetate. On the radiation polymerization of vinyl acetate in the solution of acetic acid and water, the relationships between the degrees of polymerization and solvent compositionsa re almost same as that of polymerizationr ates. The G values of polymerization-initiatioarne determinedto be Gⁱⁿ_VAc=10.6, Gⁱⁿ_Ac0H=52, Gⁱⁿ_H2O=480 and Gⁱⁿ_UAc=23, 000 respectively.

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The effects of vinyl compounds and their related substances on the polymerization of styrene by stannic chloride in benzene solution are studies. Vinyl phenyl ether, vinyl methyl ether and vinyl acetate are compared here as transfer agents. Although the mechanisms of the transfer reaction by vinyl polymers are so obscure to be unable to interprete, all of these monomers are found to be simple transfer agents. Vinyl acetate and its polymer have large values of transfer constants and it coincides to the fact that the copolymerization between styrene and vinyl acetate or the homopolymerizationo f the latter is very difficultt o occur.

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The effects of vinyl compounds and their related substances on the polymerization of styrene by stannic chloride in benzene solution are studies. Vinyl phenyl ether, vinyl methyl ether and vinyl acetate are compared here as transfer agents. Although the mechanisms of the transfer reaction by vinyl polymers are so obscure to be unable to interprete, all of these monomers are found to be simple transfer agents. Vinyl acetate and its polymer have large values of transfer constants and it coincides to the fact that the copolymerization between styrene and vinyl acetate or the homopolymerizationo f the latter is very difficultt o occur.

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