The stress relaxation moduli of cellulose acetates and nitrates with different degrees of OH substitution were observed over 0.1-10⁵ seconds at the frozen state and in the water. The relaxation spectrum was calculated by the 1-st order approximate method from each relaxation curve. Each spectrum is order of 10⁹ dynes/cm at the frozen state but that is 10⁸ dynes/cm in the water. The shaps of relaxation spectra were nearly box distribution in the frozen state but these of cellulose acetates of low OH substitution changed in the water. A linear relationship was observed between the initial modulus of elasticity and OH substitution in the both states at each temperature.

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The creep properties of mechanically conditioned cellulose triacetate were studied under various stress for 10 hrs at different temperatures. The following equation was obtained from the experimental data among a stress (σ), a strain (γ) and the time (t) and in accord with observation on cellulose trinitrate and metals. This equation does not holed at large stress and high temperature. The instant elastic compliance J_o and the parameter α decreases with increase of the inverse of absolute temperature (1/T) but the parameter β₀ increases. A composite creep curve was reduced by translating each curve along the time axis.

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Thermal conductivity of nitrocellulose in acetone solution was measured in the whole range of concentrations at 25°C. The method of measurement obtainable relative values of the conductivity was improved, special caution being paid on eliminating possible errors in the thermal resistance of the glass plate (as a standard) in contact with the sample solution and in the measurement of the thickness of the sample solution. Thermal conductvity of nitrocellulose is nearly equal to that of acetone, and its change with concentration and with the degree of polymerization was not obserbed.

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Velocity and attenuation of both transverse and longitudinal waves are measured in polystyrene in the frequency range from 0. 5 to 5MC/sec and the temperature range from 20°C to 120°C. It is found that temperature dependency of the dynamic shear and bulk modulus are approximately the same. The apparent activation energies associated with the shear and bulk deformation are at least approximately the same, 70kcal/mol. Longitudinal wave losses in polystyrene are accounted for by shear viscosity and partly by volume viscosity.

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The Permeability constants of various polyethylen to nitrogen, oxygen, carbondioxid, water vapor and organic vapors were examined. Linearity could be found between log P and log α: where P is permeability constant, and α is amorphous content. P and D (Diffusion constant) to nonpolar gas like nitrogen are aproximately proportioned linearly to amorphous content, but S (Solubility constant) somewhat changes in proportioned to amorphous content. P to water vapor and organic vapors are aproximately proportioned linearly to amorphous content as well. In consequence, I decieded that permeation of gas and vapor through polyethylen take place in amorphous part and mainly depend on diffusion.

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Polyvinyl alcohol fibers, which were obtained by wet spinning, were heat-treated in air for a few minutes at 210-180°C and the viscosity of their water solutions was measured. The viscosity apparently decreased with boiling of the solution, but remained still higher than that of the original polyvinyl alcohol or the untreated fiber. Even if heat treatment of the fibers was carried out in a wet process, for instance, in saturated aqueous solution of sodium sulphate for 2 hours at 125 or 120°C, the above mentioned phenemenon was still observed. Therefore, the cause of this phenomenon should not be ascribed only to air. In the case of the fiber obtained from the pure polyvinyl alcohol, which was more carefully produced, the above phenomenon was not observed. The increase of the viscosity by heat treatment should not be ascribed to the state of micelle dispersion of polyvinyl alcohol, but to crosslinking or branching of polyvinyl alcohol by chemical reaction, which may be ketal formation due to a few carbonyl groups in polyvinyl alcohol.

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Degradation of polyvinylalcohol heated in dimethylsulfoxide was followed viscometrically. It seems to be distinguishable by two steps: The first decayes within about ten hours, and its activation energy is 6.6kcal/mol. This suggests the existence of relatively weak bond. The formation of this bond depends on the polymerization conditions, especially on the degree of conversion. Carbonyl group probably existing in the main chain of the polymer molecule appears to be the cause of the splitting. The activation energy for second step is 15.0kcal/mol. The probability of the splitting increases proportionally with heating time and concentration of the solution for every specimen of for polyvinlyalcohol. Accordingly, this step seems to be the random degradation of the main chain by oxidation.

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Vinyl benzoate (VB), vinyl propionate (VP), vinyl butyrate (VBu), vinyl monochloroacetate (VCAc) and vinyl acetate (VAc) were polymerized in bulk with 2, 2′-azobisisobutyronitrile as an initiator. It was observed that the content of 1, 2 glycol structure, α, in so obtained polyvinyl alcohol was varied with the structure of parent vinyl ester in next order.
The relation between α and polymerization temperature, T, in VB is αVB= 0.15 exp {-1, 950/RT}, while it in VAc is αVAc=0.103 exp {-1, 460/_RT}. Then, the value αVB/αVAc is 0.7 at 60°C and 0.6 at 0°C. However, some branches may exist in polyvinyl alcohol derived from the VB and the swelling degree or solubility of the polyvinyl alcohol in water is much larger than common one derived from VAc.

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Vinyl acetate (VAc) and Vinyl benzoate (VB) were copolymerized at 60°C. The determined monomer reactivity ratios were r₁(VAc) = 0.6 and r₂(VB) =1.3. The content of 1.2 glycol structure in VAc-VB linkage was less than it in polyvinyl acetate and more than it in polyvinyl benzoate. Namely, the content in VAc-VB linkage was 0.90 mol %, while it in polyvinyl acetate and polyvinyl benzoate was 1.14 and 0.79 mol % respectively.

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The reactions between urea and formaldehyde in the presence of methanol and water by the strong alkali catalyzed method were studied under the various compositions of these components. The soluble low molecular weight condensates contain methoxy, dimethylene ether including uron type ring and methylol groups, but not methylene linkages. These compositions were studies in detail by the colorimetric, modified iodiometric method and infrared spectroscopy. The methylation of methylol group ocurrs substantially above 1×10^-2mol/l alkali concentration, but the formation of dimethylene ether linkage happens at lower alkali concentration than the case of methylation, both methoxy and dimethylene ether linkages tend to decompose at very high alkali concentration.

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The effects of counterions formed from catalysts were studied on the termination and transfer reaction in the cationic polymerization of styrene. Boron trifluoride-diethyl ether, mono-and di-acetic acid and methanol complexes were used as catalysts. In ethylene chloride solvent at 30°C, the solvent transfer constants decreased in the following order, BF₃·CH₈OH>BF₃·CH₃CO₂H>BF₃·2CH₃CO2H>BF3·O(C₂H₅)₂, and spontaneous termination constants were in the reverse order. These differences of rate constants based upon the kind of complex were found to be smaller than in the case of the Friedel-Crafts catalysts previously reported.

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In the benzene solution of fractionated poly-α-methylstyrene obtained in cationic polymerization at low temperature, intrinsic viscosities and osmotic pressure were determined, and following equation was obtained;
In the critical consolute solution consisting of methanol (20.6 vol%)-benzene (79.4 vol%), following relation was also obtained.
From these results, it was found that (r₀²/r₀f^1/2)=2.73. Comparing this value with that for polystyrene, it is concluded that methyl-groups attaching to α-carbon hinder the free rotation of carbon chain. There were no differences in behavior of solution between benzenesoluble polymer and partially insoluble one.

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Four peroxides were synthesized and used as initiators for polymerization. Two of them were expected to produce one diradical and two monoradicals and the others to produce only one diradical by their thermal decompositions. In the presence of them the polymerizations of styrene and methyl methacrylate were carried out at 60°C. The square root rule as to the peroxide concentration was found to hold. The curves from the plots of the reciprocal degrees of polymerization against the rates were compared with the socalled monoradical line. In the case of the polymerization of styrene catalyzed by di-t-butyl diperadipate, the curve was found to be under the monoradical line. Two mechanisms that the step-wise decomposition of it occurred and that the diradical perticipated partially in the polymerization processes may be suggested from this fact. However, the former hypothesis may be fovorable on the basis of the polymerization catalyzed by diperphthalate in which the degree of polymerization increased at higher conversion.

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Formations of H₂O and CO₂ by oxidation of polyethylene were traced with time. Polyethylene samples used were Z-3859 and 0.07% phenyl-β-naphthylamine added, and oxidations were carried out between 120 and 160°C The process of water formation was similar to that of oxygen absorption, and i.e., the rate of water formation augmented autocatalytically and reached max. value, then decreased. At the lower temperatures than 150°C, apparent activation energies obtained from max. rates of water formation were both 23.5 kcal/mol. The induction periods were observed in water formation and induction periods were increased with addition of antioxidants. The amounts of oxygen distributed on oxidation products were obtained, and it is concluded that 42-46% of oxygen used fixed as water, 6-15% as CO₂, 2-8% as volatile acids, and 49-34% fixed on polyethylene.

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Some unsymmetrical compounds were synthesized, which contain acryloyl or epoxy group as one terminal group, and one of acryloyl, epoxy, ester and urethane groups as the other (e.g., where X=O, NH; R=(CH₂)₅, p-C₆H₄). Syntheses of polymers containing two different linkages were attempted by the polyaddition or polyaddition-condensation reactions of above compounds with aliphatic diamine, diol or amino-alcohol of 4 or 6 carbon atoms. The polyaddition-condensations between hexamethylenediamine and each of ethyl N-acryloylp-aminobenzoate, N-carbethoxy-p-aminobenzoic acid glycidyl ester or N-carbethoxy-ε-aminocaproic acid glycidyl ester produced light yellow hard resins with a softening point of ca. 140°C.

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Some aliphatic diesters and diurethanes were prepared by the reactions of adipoyl dichloride or tetramethylenediisocyanate with ε-amnocaproate, ε-oxycaproate, N-carbethoxyhexamethylenediamine, or N-carbethoxy-6-aminohexanol. They contain two amide, two ester, two urea, or two urethane groups in polymethylene linkage between two terminal ester or urethane groups. By the polycondensation reactions of these compounds with aliphatic diamines or diols of 4 or 6 carbon atoms, various polymers having the regular structure of -A-A-B-B- type were obtained. Among them the polyamide-ureas are fiber-forming, but the polyamide-esters, the polyurea-esters and the polyurethane-esters are not.

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Nylon 6 fibre subjected to steam-setting exhibits many different properties from that to dry-heat-setting. Undrawn and drawn nylon 6 filaments were subjected, under tension or tensionless state, to dry-heat-setting at 140, 160 and 180°C and to steam-setting at 110°C, 120°C and 130°C. Young's modulus and bending modulus were measured and the variation of density resulted from dry-heat-setting were observed with a density-gradient tube making use of dry n-butyl bromide and benzene as the medium. These results show that specific gravity is increased by heat-setting, processes especially greatly by steam-setting. This is supposed to be caused by the increase of the degree of crystallinity. Young's modulus seems, however, to be rather decreased by steam-setting; this may be attributed to the role of water molecules in loosening the molecular spacement of fibrous structure in the case of steam-setting.

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Drawn or undrawn nylon 6 Fibre subjected to dry-heat-setting or steam-setting were dyed with an acid dyestuff and a direct dyestuff. Their absorption isotherms were determined. And also the diffusion constant of a dispersed dyestuff were measured on nylon 6 gut by applying Kramer's method. The overall results showed that the diffusion constant and the rate of absorption were generally increased by steam-setting. The higher the temperature of treatment became, the more conspicuous this tendency became. In this case, the increase of the tension used in the treatment reduced the dyeing property. Dry-heat-setting gavehowever the reverse tendency (up to about 160°C), but the effect of the tension was similar to steamsetting. Same tendency was observed with undrawn nylon 6. Therefore we concluded that the elevation of dyeing property was caused not by decreasing the orientation of crystallites but making loose the packness of intermolecular structure in amorphous region by hot water vapour.

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The hardening reaction of o-cresol novolac was examined by the same method of phenol novolac. In this experiment it was found that the viscosity of A stage was increased by heating and it was found that insoluble resin was prepared by heating of higher temperature and longer time than that of phenol novolac and its viscosity was larger, the rate of hardening was more slight than those of phenol novolac and its solubility was different by solvents. The activation Energy Qη, Qk were also larger than that of phenol novolac and phenol resol. Therefore it was found that o-cresol novolac was more difficult to react with hexamine than phenol novolac with hexamine. From these experiment it was cleared that the reaction of o-cresol novolac with hexamine was different from the reaction of phenol novolac with hexamine.

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