The dielectric properties of cellulose nitrate plastics containing 0-40% D.B.P. as plasticizer were measured over the frequency range from 50 kc to 2.5 Mc and the temperature range from-50°C to 150°C by using the Q-meter. For the unplasticized cellulose nitrate, only one anomalous dispersion could be observed in these temperature and frequency ranges. The apparent activation energy was 12 kcal/mol. It is reasonable to consider that this dispersion is caused by the movement of the dipoles of the side chains, since the value of the apparent activation energy is too small to activate the segmental motion of the main chains. For each of the sample containing 30-40% D.B. P., only one anomalous dispersion was measured in the observed range. The apparent activation energy was about 30 kcal/mol. This dispersion may be considered to be due to the movement of the segments which are loosened by the plasticizer. For each of the samples containing 10-20% D. B. P., superposed two dispersions were observed. Although we can not calculate the apparent activation energy, we postulate that the cause of the upper dispersion may be the segmental motion of the main chai

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Tensile stress-strain curves for a drawn polyethylene filament have been measured over the temperature range from 0°C to 80°C at seven different rates of extension covering a range from 10 to 1000%/min. The effects of the rate of extension and temperature on the ultimate strain, tensile strength, yield strength and the initial elastic modulus were studied by timetemperature superposition method which was extended so as to take account of the amount of crystallinity and orientation. When the extended superposition method is applied to the data on the tensile strength and yield strength, reasonable values for the shift factor along the log strain rate axis are obtained in spite of the fact that in these cases the deformation exceeds the range of linear viscoelasticity. Although the horizontal shift factors are slightly different each other, activation energies are all about 20 kcal/mol. On the other hand an activation energy obtained by application of same superposition method to the initial elastic modulus is unreasonably large as compared with that obtained by Nagamatsu and his coworkers in the stress relaxation experiment. This disagreement may be attributed to the non-linearity of viscoelasticity.

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Induction period of acrylonitrile polymerization initiated by persulfate-sodium-bisulfite and persulfate-triethanolamine redox system in aqueous medium was measured for various initiator concentrations and polymerization temperature. It was found that the induction period was proportional to the reciprocal of both monomer and intiator concentration respectively. Activation energies of initiation were calculated from values of the induction period. Kinetics of the inhibition of polymerization was studied theoretically and the experimental results could be explained fairly well with the considerations.

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The interaction between proton donating groups in thiolignin and π electrons in rubber, is considered to be one of the most important factors for the reinforcement of rubber by thiolignin. In this report, some model compounds of thiolignin and of styrene-butadiene copolymer (SBR) were chosen, and the interaction between them were investigated infrared. spectroscopically, in which the OH stretching vibration of the proton donating lignin models in CCl₄, was measured in the presence of the excess of rubber models. As the result, it is confirmed that even the guaiacyl type OH group forms the hydrogen bond with π electron, in which especially when carbonyl group exists in the para position to OH group, much stronger hydrogen bond is formed. The alcoholic OH group also forms the hydrogen bond with π electron and and the frequency shift is the same order with the guaiacyl OH group having carbonyl group at its para position. As for rubber models generally, the shift is larger for a compound having C=C double bond than that having benzene ring, while the fraction of the hydrogen bond formation is favarable for the latter.

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The effects of irradiation atomosphere, dose rate, solvent and solvent/monomer ratio on the grafting of styrene to nylon 6 film were studied. It was found that the induction period of the grafting in the presence of air was very short. The amount of grafted polystyrene after an integrated dose of 1.0×10⁵ roentgens was inversely proportional to the square root of the intensity between 50 and 2, 000 roentogen/min. The effect of the solvent on the grafting was very remarkable. Organic solvents studied in this experiment were methanol, ethanol, nbutanol, sec-butanol, tert-butanol, iso-butanol, benzene, acetone, carbon tetrachloride, dimethylformamide and m-cresol. The addition of 1% water or 3% methanol to the grafting mixtures noticeably accerelated the rate of grafting. The lower the carbon chain length of aliphatic alcohol, the more effective was the accerelation of the grafting. In styrene-alcohol mixtures three maxima of the ammount of grafting were observed for monomer/solvent ratio. In the mixture of styrene and organic solvent except methanol, a slight or no increase of accerelation was observed. Some experiments on the grafting of styrene in the presence of divinylbenzene were also carried out.

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The effects of temperature (15-30°C) and relative humidity (40-80%) on the adhesion of polyethylene to cellophane were studied. The effect of relative humidity is larger than that of temperature and the adhesive strength decreases with the increase of relative humidity. The relationship between the adhesion of polyethylene to cellophane and the properties of cellophane was also studied. The adhesive strength decreases with the softner content in cellophane.

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Isobutyl vinyl ether was polymerized by metal sulfate-sulfuric acid complexes as one of heterogeneous catalysts. It was found that high molecular weight polymers were obtained at room temperature by complexes of sulfuric acid and sulfate of metal belonging to the Groups II, III, VI or VIII. Mg or Cr complex which was one of the most active catalysts, was mainly chosen to study the effects of the concentration of catalyst and monomer, and of temperature. Compared with the homogeneous polymerization, the most remarkable characteristic of these heterogeneous catalysts was that the molecular weight of polymers did not decrease with the rise of polymerization temperature. This tendency was also observed in Florida-earth (acidic clay) catalyst, and in this case the molecular weight of polymers increased with the increase of temperature.

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