Cationic polymerizability of α, β-unsaturated ethers are discussed in particular attention to their geometrical structure and kinetic behavior. The ethers investigated include alkenyl alkyl, phenyl vinyl, styryl ethyl and β-chlorovinyl ethyl ethers. 1, 2-Dial-koxyethylenes and benzofuran have also been studied. Comparisons of their general behavior in polymerization with that in the acid-catalyzed hydrolysis, which involves the rate-determining protonation, have manifested an important discrimination in the nature of the transition states between the two reactions. It is generally concluded for the cationic polymerization that rotation about the C-C bond of the polymer end unit is restricted in the transition state and that its structure may be represented by a π-complex-type or cyclic model such as the following:

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For the study of deuteration mechanism of PVA, the exchange reaction of active hydrogen atoms between PVA membranes (heat treated and non-treated) and the vapors of water and aliphatic alcohols (methanol, ethanol and n-propanol) were investigated.
The degree of exchange reaction was measured by IR-spectroscopic method.
At first, the deuteration rate of PVA with heavy water vapor was studied, and the following results were obtained:
(1) Except the early stage of reaction, the reaction rates had no relation to the membrane thickness PVA.
(2) The apparent rates of deuteration decreased at higher reaction temperature under a definite vapor pressure.
(3) The degree of deuteration of PVA amounted to 100% at equilibrium irrespective of heat treatment.
Next, the exchange reactions were studied by deuteration and rehydrogenation with lower aliphatic alcohols which seemed unableto diffuse into the crystalline region of PVA, and the results were as follows:
The apparent reaction rates were (1) lower in comparison with those by heavy water, (2) in inverse proportion to the thickness of membranes, (3) not influenced by the degree of crystallinity of PVA, (4) faster at higher reaction temperature, and (5) in proportion to the vapor pressure of alcohols. And the degree of reaction amounted to 100% at equilibrium as same as the reaction with heavy water.
From above results it was supposed that the exchange reaction of active hydrogen atoms between alcohol and PVA must proceed by “proton transfer” in crystalline region, and probably in amorphous region too.
This mechanism may be also applied partially to the exchange reaction with heavy water, especially in crystalline region.

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Polymerization of vinyl monomers initiated with cellulose acetate fiber was carried out in the presence of water, carbon tetrachloride or n-hexane, and the relationship between the polymerizability and the condition of polymerization system was examined. In the case of styrene, small amount of polymer was obtained. With the exception of styrene, only acrylates and methacrylates showed the polymerizability. Some of monomers showed either higher or lower polymerizability by the addition of water.
The acceleration of polymerization by carbon tetrachloride was more or less observed in each monomer. The acceleration effect of n-hexane was only observed in the case of methyl methacrylate. Copolymerization of methyl methacrylate and styrene was carried out in the presence or absence of carbon tetrachloride, and the deviation of the values of monomer reactivity ratio from reported ones by Mayo et al. was discussed.

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The polymerization mechanism of acrylamide in aqueous system initiated by ceric ion was studied. In this system, the rate of polymerization in the concentrations of ceric ion lower than 0.9-1.0×10^-3 mol/l differs from that in the higher concentrations as follows respectively,
where k₁, k₂, and k₃ are the rate constants of the reaction.
When only the concentration of ceric ion was varied. a maximum rate of polymerization appeared, and it shifts to the higher concentration of ceric ion with increasing the concentration of acrylamide. Some rate constants in this system were obtained.

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Elastic moduli of the crystalline regions in the direction perpendicular to the chain axis (E_t) for the isotactic polybutene-1 (it-PB-1) were determined by an X-ray diffraction method. The moduli observed were as follows:
it-PB-1:
It is reasonable that E_t-values for the (110) and (220) planes were obtained equally since these lattice planes are parallel to each other. Judging from the fact that the (110) and (300) planes have the same E_t-value, it may be considered that there is no anisotropy of the interchain forces in the basal plane.
In the case of polyethylene (PE) and isotactic polypropylene (it-PP) there is practically no anisotrop y in their E_t-values, either; E_t-values for PE and it-PP are represented by 4 ×10⁴ and 3 × 104 kg/cm², respectively. Comparing the E_t-values for these polymers and considering that the cr ystal structures of it-PP and it-PB-1 are very similar, we may conclude that Et-value decreases with increasing the length of side chain. This may be explained as follows; interchain distance is enlarged with increa sing the length of side chain, which results in a decreased number of effective attraction centers per unit area, consequently, in a decreased interchain force.

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This paper describes the difference between the charges generated by sliding and rolling friction on an amorphous polyethyleneterephtalate (PET) film against several rubbing materials. The normal loads of friction were below 40 g/cm and the frictional velocity was held at 1.1 cm/sec.
The local distribution of charges and the charging curves with the number of rubs were observed by means of a scanning micro probe. The electrification characteristics of PET film were expressed in terms of the apparent electricity (q_a).
When the rubbing material is metal, the mechanism of charge transfer at a contact does not seem to be affected by the methods of friction. The q_a values by sliding become larger about 4 to 15-folds than those by rolling. This difference may be caused by the real contact areas of the PET film.
In the case of sliding with good insulator, the charging behaviour is quite different from those of rolling or metal-friction. There is not large difference in the q_a values, but sometimes the sign reverse occures between sliding and rolling.
When the q_a values of PET film by rolling are compared with those of polypropylene film in the previous paper, it is observed to hold some aditivity among the qa values against the rubbing materials.
Although the qa value is affected by the surface roughness of samples and rubbing materials, it means to be a value propotional to such the electrification characteristic of a material as the difference of the work function of metals.
Therefore, the q_a value is useful for comparing the frictional electricity on the basis of chemical and physical structure of polymers.

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The possibility of finding the heterolinkages of the various kinds of polycondensation copolymers by high resolution NMR was examined and the followings became clear.
(1) In case of the homologous type of copolymers (copolyester ctc), it is in general able to detect the heterolinkages when the units to be observed are joined by the aromatic and the saturated aliphatic groups. And the easiness of the detection is as follows; copolyester >copolyamide >copolyurethane> copolyurea.
(2) In case of the heterogeneous type of copolymers (copolyurethane-carbonate, copolyamideurea, copolyamide-urethane, copolyurea-urethane, copolyester-urethane, copolyester-amide), the possibility is determined by the difference of the aromaticity and the saturated aliphaticity joined to the unit to be observed and also by the difference of the kinds of linkages.
(3) Poly (neopentyl terephthalate-co-sebacate) obtained by the molten-state polycondensation is almost random and copolyurethane-carbonate obtained by the interfacial polycondensation have somewhat blockness character.

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This paper describes the influence of ambient temperature on the frictional electricity of polymer films. The polymers examined are polycarbonate (PC), polyvinyl chloride (PVC), polyethyleneterephthalate (PET) and polypropylene (PP). Because the electrical resistivities of those polymers are very high even at near 100°C, the charges lost by leakage are negligibly small. The rubbing material is platinum (Pt), but for the sample of PC, polyvinyl chloride is also used.
The frictional electricity was expressed by the Q₁ value, which was the charge generated on the sample of film by one rub at a constant rubbing condition (normal load: below 20 g/cm, rubbing velocity: 1.1 cm/sec), under the ambient temperature varying betwen -20°C and 120°C at a constant rate: 1°C/min. Before measurements of the Q₁ value by means of a scanning micro probe, the sample and the rubbing material were wiped quickly by the gauze absorbed methanol to eliminate the residual charge and to clean their surfaces. Usually, the sample was stuck on a Teflon block with an adhesive.
In order to discuss the temperature dependence of the Q₁ value, the viscoelastic properties of polymer films were measured by a tan δ meter.
The results are as follows:(1) When the visco-elastic properties of the contacting materials, change moderately with respect to the ambient temperature, the variation of the Q₁ value is also slight.
(2) When the contacting materials have glass transition etc. within the temperature range of the present work, the Q₁ value increases with temperature to a maximum and then falls. For this behavior, it is considered that the visco-elastic properties of the contacting materials influence their frictional electricity, on the basis of the interfacial adhesion mechanism which has been interpreted by Grosch on the friction of rubber.
(3) In the case of PP, the Q₁ value gets to a maximum near 70°C and then decreases rapidly with increasing temperature. This decrease of the Q₁ value seems to be due to the thermal oxidation of the surface of PP. In fact, the activation energy of the thermal oxidation of PP, which is obtained from the time dependence of the Q₁ value at high temperature, is 25.7 kcal/mol and agrees well with those in the literature.

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Maleic acid (MA)-ethyl crotonate (A), MA-stilbene (B) and MA-diphenyl acrylamide (C) copolymers were prepared by hydrolysis of the alternative copolymers of maleic anhydride (MAn) and the corresponding comonomers. The behaviors of acid anhydride formation and potentiometric titration of A were similar to those of MA-styrene copolymer. The behaviors of C were distinctly different from those of MA-methyl acrylate copolymer which contains an acrylic monomer unit as C. B, in which the comonomer contains two bulky substituents, showed a much less ability for acid anhydride formation and much greater one for ionization than the other MA-copolymers. Further, diethyl fumarate was copolymerized with allyl acetate and isopropenyl acetate, then the copolymers obtained were hydrolyzed to MA-allyl alcohol (D) and MA-isopropenyl alcohol (E), respectively. The behaviors of lactonization and acid anhydride formation of D and E were remarkably different from those of the corresponding copolymers, which were derived from the MAn-copolymers and have the same planer structures as them. Such results were briefly discussed on the basis of the stereo-structures of these copolymers.

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Emulsion copolymerization of acrolein (M1) with styrene, methyl methacrylate (MMA), methyl acrylate (MA), ethyl acrylate (EA), and n-butyl acrylate were studied using sodium dodecyl sulfate (SDS) as an emulsifier. Monomer reactivity ratios were as follows.
r₁ = 0.034r₂ = 0.32 (for styrene)
r₁ = 0.5r₂ = 1.0 (for MMA)
r₁ = 1.6 r₂ = 0.6 (for acrylic esters)
The rate of emulsion copolymerization of acrolein with styrene was much higher than each homopolymerization rate of acrolein and styrene, and showed a maximum when the monomer mixture contained about 70 mol% acrolein.
Alkali hydrolysis of acrolein-acrylic ester copolymers was studied in latex state. Acryl esters having longer alkyl groups were found to be more stable to alkali, because of the hydrophobic property of the esters with longer alkyl chains.

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Crosslinking of acrolein-ethyl acrylate copolymers was investigated in acidic condition. Polyol, urea, melamine derivatives and diamine were effective agents for the reaction. Urea was a paticularly useful agent.
The thermal stability of crosslinked copolymer with urea was much higher than that of uncrosslinked copolymer. UV irradiation caused chain scissions along the main chain of copolymer. Melamine derivatives were effective stabilizers for the copolymers.

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It was found that the styrene-butadiene rubber (SBR) degraded with ultraviolet light had an ability of emulsifying toluene-water system. In order to clarify this phenomenon, the relationships among the emulsifying ability of degraded SBR and the degradation methods, degradation conditions and the polar groups in degraded SBR were studied. The molecular weight of SBR was remarkably decreased by the irradiation of ultraviolet light to SBR solution, or by heating toluene solution under the existence of solvent peroxides, and the emulsifying ability of degraded SBR increased with the decrease of molecular weight of SBR. On the contrary, the SBR ozonide did not indicate a good emulsifying ability, though the molecular weight of SBR remarkably decreased. The polar groups such as carboxyl, peroxidic bond in degraded SBR were found and the emulsifying ability of degraded SBR was enhanced when the degradation reaction proceeded in the oxygen atmosphere. Moreover, the methyl methacrylate copolymer containing trace amounts of acrylic acid indicated similar emulsifying ability to degraded SBR. In the emulsion of toluene-water-degraded SBR system, the emulsion was W/O type when the volume fraction of water was less than 0.65 and the emulsion was 01W type when the volu me fraction of water was more than 0.70. From these results, it was deduced that the emulsifying ability of degraded SBR was due to the existence of polar groups such as carboxyl, that is, the degraded SBR behaved as an oilsoluble polymeric surfactant.

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