The molecular weights of the fractionated polydimethyl-itaconate were determined by vapor pressure osmometry, and the following relationship between intrinsic viscosity [η] and number average molecular weight Mn was obtained.
[η] =4.12×10^-4M_n^0.0645 where [η] was measured in benzene at 30°C, and expressed in dl/g.
Then, the monomer transfer constants of dimethyl itaconate at various temperatures were datemmined kinetically as follows: 1×10^-3 at 40°C, 2×10^-3 at 50°C and 3.4×10^-3 at 60°C.
Further, the k_t^1/2/kp at 40-60°C were evaluated as 57-85. From these data, it is understandable that, in the radical polymerization of dimethyl itaconate, the monomer chain transfer and termination reactions occur more readily than in that of the other common monomers.

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Polystyrene is degraded in the mixed solvents of benzene and n-hexane containing the salt of monochloro acetic acid and aniline, and a little amount of acetone between coaxial electrodes by high frequency oscillating ions. Voltage and frequency of degradation are 400V and 11.1Mc, respectively.
From the relation between [η] / [η] _{30, B} and the decrease of intrinsic viscosity (the decrease of DP after the consumption of equal electric power), it was found that the degradation rate was accelerated as the intrinsic viscosity in reaction solution became larger.
In other words, it may be said that the configuration of polymer molecule has much relation with degradation rate.

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Crazing was observed in the inner parts of polycarbonate and polystyrene specimens which were immersed in warm water or steam for long periods. As the water crazing was observed on the stress-free specimen, it seems to be initiated by the penetration of water molecule into the specimen. The craze is orbicular and showed many rings as the “annual ring”. The ring craze was composed of oriented matter and vanished by the thermal treatment above their softning temperature or T_g.
Water crazing was accelerated by the residual stress and strain, contamination, blending of the low molecular weight additives, other structual imperfections and increase of temperature, but was suppressed by the molecular orientation of specimen.
Photomicrography was used for the observation of ring craze. Absorption of water, ethyl alcohol and ethylene glycol by polycarbonate and its stress relaxation in those reagents were examined at various temperatures. Initiation and propagation mechanisms of water crazing were discussed from the experimental results.

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Crystallization of stereoregular poly (viny alcohol) (PVA) films by heat-treatment under fixed length and free contraction was studied and the following results were obtained:
1) The crystallization of stereoregular PVA films at any temperature of heat-treatment procceeds in the following order:
Syndiotactic PVA>Atactic PVA>Isotactic PVA
2) The maximum degree of crystallization was obtained under fixed length of about 200-300% stretching. The cause of this phenomena was interpreted in terms of an equation of crystal growth proposed by Hoffman et al.

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General expression for the change with time of temperature difference between a solution drop and a solvent drop in a saturated vapour phase of pure solvent was derived by taking into consideration the condensation of solvent vapour to the solution drop and the heat transmission from the solution drop to the vapour phase and to the thermistor bead on which the drop was added. ₀1) When the heat transfer except condensation can completely be ignored a thermodynamic equilibrium is realized and the temperature difference between two drop (ΔT) _e is given by the well-known equation:
where, K_e= (RT₀²V₀) /ΔH, c, concentration, A_{2, v}, second virial coefficient, R, gas constant, T₀, temperature of the solvent (=temperature of the vapour phase), V₀, molar volume of solvent, ΔH, heat of condensation.
2) When the heat transfer except condensation can not be ignored, only a steady state is attainable. The temperature difference in such a state (ΔT) _s is given by an equation similar to that described above, but in this case, Ks instead of Ke should be used, where, K_s=V₀/[{(A₁k₁+A₂k₂) / (A₁k₃ΔHP0 (T0))} +ΔH/RT02], A₁, surface area of drop, A₂, area of the thermistor bead in contact with the solution drop, k₁ and k₂, surface heat transfer coefficients corresponding to vapour-solution and solution-thermistor, k3, mass transfer coefficient, P₀ (T₀), vapour pressure of pure solvent at T₀.
Effects of vapour pressure of solvent, total pressure and size of drop on the efficiency K_s/K_e were discussed theoretically and experimentally. The time required for reaching a steady state was expressed as a function of P0 (T0) and compared with experimental data, Hitachi molecular weight measurement apparatus type 115 and Mechrolab 302 (reformed in part) were utilized.
The gradual decrease in (ΔT) _s with time can be explained in terms of the change in the concentration due to the condensation of solvent vapour.

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