The viscosities of polyvinyl chloride compounds were measured by vibrating reed method, to examine the relations to diffusion coefficients of plasticizers in the compounds. The viscosities at 50cps, η ₅₀ were measured for the plasticizers, TCP, DOP and DOA, over the range of 20-120°C, and 20-60 percent plasticizer. At 100-120°C, η ₅₀ were govemed by the equation, logη ₅₀=3.4logw₂+K, where w₂ is weight fraction of resin, but at lower temperatures, η₅₀ increased more rapidly than the equation. Linearity could not be found between logη₅₀ and 1/T, where T is absolute temperature, and the apparent energy of activation of η₅₀ decreased with temperature, and at 20-50°C, were almost equal to that of diffusion coefficient.

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The glassy transition of polyvinyl alcohol depends on the quantity of the moisture involved and also on the history of heat treatments. The effect of the heat treatment were considered to arise not only from the dehydration from the specimens, but also from the rearrangement of O-O hydrogen bonds from the metastable (inter-molecular) position into stable (intramolecular) position with increasing temperature. Even at a temperature above the glassy transition point, internal rotation of the chain have not sufficient large amplitude nor a high frequency. From the theoritical analysis of the results of n.m.r, following conclusion may be deduced that a rod like chain segments associated with intramolecular hydrogen bond begins the molecular rotation gradually with increasing temperature about the long chain axis. Farthemmore the experimental second moment of n. m. r shows a transition between 130°C and 150°C, which suggests that this transition does not results from the premelt of a fine crystallite but from the molecular rotation in the crystallite.

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Polymerization of vinyl acetate in the presence of crotonaldehyde was studied. Polymeri-zation rate is proportional to (AZN)(0.70). The data of polymerization rate is well expressed by the Kice's kinetic equation, and it was found that the chain transfer was predominant and aldehyde radical contributed both to the reinitiation of the chain and crosstermination, and rate constants of these reactions were determined. An equation on the polymerization degree was derived on the base of the chain transfer mechanism of crotonaldehyde, and chain transfer constant was determined from this equation,
Cχ=0.18 (60°C)
This value coincided exactly with one obtained from the Kice's equation.

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Polymerizatiofn vinyla cetatei n the presenceo f benzaldehydew as studied.P olymerizationr ate is proportionatlo (AZN) ^0.65 and welle xpressebd y Kice'sk inetiecq uation. From the data of polymerizatiroant e, d egreeo f polymerizatioann d Carbonylc ontenti n polyvinyl alcoholi, t was concludedt hat benzaldehydaec tsa s a retardelri kec rotonaldehyde.
Cχ=2.3×10^-2 (60°C)

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In redox copolymerization of acrylonitrile, methylacrylate, and methyl methacrylate initiated by K ₂ S₂ O ₈-sodium bisulfite in aqueous medium, it is measured the monomer reactivity ratios (MRR) of these monomers by the method of Mayo and Fineman. The results obtained are as follows:
Acrylonitrile (M ₁)-methylacryiate (M ₂)(at20°C)
r₁=0.15±0.03
r₂=1.05±0.40
and
Acrylonitrile (M₁)-methyl methacrylate (M₂)(at 20°C)
r₁=0.75±0.20
r₂=1.22±0.20
These values are nearly equal to the reference values of Mayo et al and American Cyanamid Co. obtained by bulk polymerization at 60°C. It is also measured the MRR values of acrylonitrile and methyl acrylate at various temperatures and found that the change of the values is fairly small. Moreover, the computation of the composition distribution of the copolymers has been performed by the Skeist method.

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In the synthesis of butadiene from ethylalcohol and acetaldehyde, the main reactions were devided into the two reactions, i.e.(1) the polycondensation of aldehydes, (2) the reductiondehydration of the aldehydes with ethylalcohol, and the rate equations were derived on the assumption that the rate determining step is to be the interaction of the adsorbed molecules. The amount of the produced butadiene, and the reduced amounts of CHO group and alcohol were calculated applying the various constants which were observed on each step of the reactions described as (1) and (2). On the other hand these amounts were observed experimentally, and compared with the calculated values. The both values agreed satisfactorily with each other, and hence it was concluded that the nature of this synthesis is the polycondensation aldehydes containing ethylalcohol as a stopper reactant. Although the activity of Ta ₂O ₅-SiO ₂ catalyst decreased gradually, the observed yield of butadiene versus degree of conversion of CHO group agreed well with theoretical calculation, this makes us easier to control the reaction condition for butadiene synthesis.

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