Two types of styrene (St)-butadiene (Bd) block copolymers, St-Bd-St-Bd-St (A-type) and St-Bd-St (B-type), were prepared in cyclohexane by the usual living anionic polymerization with secondary butyl lithium as a catalyst.
Electron microscope and X-ray small angle scattering were applied to observe their fine structures in solid state.
The melt behavior and the impact strength depended not only on the both block chain lengths but also on the repeating numbers of the both components. The A-type showed the same value of impact strength as the B-type, when styrene content was less than 84%. However, the value of the A-type became twice as much as the B-type in case of 88% styrene content.

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By means of differential scanning calolimeter, isotactic polystyrene crystallized in different conditions was studied, and the glass transition temperature was compared to that of atactic polystyrene.
In the thermogram of the sample quenched from the melt (crystallinity X_c=0), the peak of melting at 225.5-226°C, the exothermic peak in the range from 150°C to 190°C and the glass transition temperature at 83°C were found. No exothermic peak was found in the samples cooled slowly, for example, cooled at 16°C/min from the melt to the room temperature (X_c=12%) or crystallized at 170°C for 30min (X_c=30%). In the quenched samples, crystalline patterns observed by X-ray diffractometer equipped with a heating cell appeared from 130°C, so that the exothermic peak in the thermograms was attributed to the cold crystallization.
As the rate of crystallization of polystyrene was rather small, the two peaks, main and sub peaks of melting were observed clearly in the samples crystallized isothermaly from both the melt and the quenched sample in comparison with the other polymers. The temperatures of sub peak of melting were observed slightly above the annealing temperatures. The multiple peaks were obtained easily by the stepwise annealing.
Glass transition temperature of isotactic polystyrene varied from 80°C to 85°C and thermograms near the glass transition were also affected by thermal history. By heattreatment at 70-80°C, endothermic peak of the quenched sample became larger with prolonged treatment in comparison with atactic polystyrene. Double peaks observed in atactic polystyrene which was treated below the temperature of glass transition were not obtained in the case of isotactic polystyrene. It is estimated that the structure of amorphous state was different between the amorphous isotactic polystyrene and the atactic polystyrene. By the heat-treatment near the glass transition temperature, thermal behavior of the samples previously crystallized at 130-190°C were much different from the quenched sample. It is concluded that the structure of amorphous state was affected by the difference in crystalline region which was formed by heat-treatment and observed as melting sub peak in fusion curve.

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Gas phase graft copolymerization of butadiene (BD) to polyvinylchloride (PVC) powder induced by γ-ray at 60°C was studied. The grafting was carried out under 760 mmHg vapor pressure of BD. The kinetical features of the grafting were as follows.
1) The rate of grafting decreased with reaction time except the initial stage of polymerization.
2) The “post-grafting” was more remarkable when the irradiation was stopped at the earlier stage of the polymerization.
3) Though BD gas contained-5vol% of oxygen, the polymerization was not impeded.
4) The degree of dehydrochlorination occurred during the graft copolymerization was less than 1: 20000 in comparison with the case that PVC was irradiated in nitrogen atmosphere instead of BD at the same condition.
From these results, it is obvious that almost grafting occurred uniformly in the solid phase of PVC powder. Furthermore, it is deduced from the kinetical studies of the polymerization that the propagation reaction is not controlled by the diffusion of monomer, but the termination is extremely suppressed.

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The effects of reaction temperature on the γ-ray-induced gas phase grafting of butadiene (BD) to polyvinylchloride (PVC) was studied. Arrhenius plots, concerning the rate of grafting, gave straight lines which slope changed at 50°C. It was suggested that the change of grafting mechanism occurred at this temperature. Viscoelastic properties of the graft copolymers molded by a mixing roll and a hot press showed that the dispersed particle-size of grafted BD constituent became smaller with increase of grafting temperature. This agreed well with the result of electron microscopic observation. Dynamic loss (E″) of both PVC and graft copolymer increased at about 50°C with the increase of temperature.
From the above results, it is assumed that the change of physical properties of the solid phase, in which graft copolymerization occurs, affects strongly the graft copolymerization reaction.

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Polymer was formed in electrolytically initiated reaction by a direct current of a rectangular wave form current at 30°C, 0°C, and -78°C from acrylonitrile dissolved in dimethylsulfoxide, saturated with sodium nitrate, potassium perchlorate, and potassium borofluoride.
The conversion by D. C. electrolysis was greater than the conversion by rectangular wave form current and a greater yield was obtained by solid state polymerization at -78°C.
The η_sp/C value of the polymers formed by rectangular wave from current at 30°C and 0°C was larger than the values of polymers which were formed by D. C. electrolysis at 30°C and 0°C, but it was smaller in the case of -78°C.
A scheme was proposed for the reaction that a part of the negative ions was neutralizrd with the positron, and the radical polymerization occured at 30°C and 0°C, but little reaction took place at -78°C.
Coloration of polymers became deep in D. C. electrolysis at 30°C and -78°C and in the reaction by rectangular wave form current at 0°C.
Colorized polymer formed has absorption bands at 305, 260 and 235 mμ in ultraviolet region. This coloration is interpreted as follows: the results of infrared spectra (1570 cm^-1) analysis made clear that the coloration may be due to the existence of C=NH groups.
This mechanism is proposed on the basis of the experiments by Yamazaki and Funt.

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Radical polymerizations of methacrylonitrile were carried out in acetone at 60°. Azobisisobutyronitrile was used as an initiator. It was found that the initial rates of polymerization (mol/l/sec) R_p and the viscosity-average degrees of polymerization DPv are expressed by the equations (1) and (2), where (m), (I) and (S) are the concentrations (mol/1) of monomer, initiator and solvent, respectively.
_??_(1)
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Copolymerization of dicyclopentadiene with sulfur dioxide was studied using radical initiators. The polysulfone obtained had no unsaturated bonds and contained two moles of sulfur dioxide for one mole of dicyclopentadiene. The polysulfone was also easily obtained without initiators in the presence of a small amount of additives such as methanol, water and pyridine. In the case of methanol as the additive the overall activation energy was about 7.4 kcal/mole.
Furthermore, cationic polymerization of dicyclopentadiene in liquid sulfur dioxide was studied.

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