In order to study the dynamic properties of high polymers, the authors tried to make an experimental apparatus. The apparatus automatically provided the information of temperature dispersion of the internal friction. The principle of this system was based on the fact that the numbers of the oscillation at interval during which the maximum amplitude damps from initial value to a given smaller value, is reversively proportional to the logarithmic decrement of the oscillating system (conjugated torsion pendulum).
The numbers of oscillation were detected photo-electrically and calculated electrically, and then logarithmic decrement is plotted on the recorder-chart.
At the same time, we designed the method based on the principle that oscillating velocity decreases with the same ratio as amplitude decrement.
The results for several high polymers obtained by use of this apparatus were given.

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The copolymerization of ethylene and styrene was carried out with Ziegler catalyst. The obtained polymers consisted of the acetone-soluble part, the structure of which was close to atactic polystyrene, and the acetone-insoluble part containing ethylene-styrene copolymer. The ratio of these two parts varied with the polymerization conditions, i.e., the acetone-soluble part decreased with increasing Al/Ti ratio and with decreasing styrene fed. The presence of the copolymer was confirmed by the IR and NMR spectra.

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Many researches have done on “Gelation point of poly condensation polymers”. But most of them dealt with systems without mono functional component.
In the case of systems containing mono functional components, stopping effect on chains or branches by mono functional components must be taken into consideration.
Equation showing gelation point of poly condensation reactants containing any functional compositions is derived._??_
where p: extent of reaction of functional group A
q: extent of reaction of functional group B.i: fraction of functional group A that belongs to j-functional component in all A.
σl: fraction of functional group B that belongs to l-functional component in all B.
f_j: functionality of j-functional component of A.
g_l: functionality of l-functional component of B.
To confirm the agreement of this equation, gelation point of various polyester compositions were determined.
One or more than two of lauric acid, adipic acid, trimellitic acid and trimellitic anhydride were reacted with one or more than two mixture of oleyl alcohol, di-ethylene glycol, tri-methylol propane and pentaerythritol. Small amount of p-toluene sulfonic acid was added as catalyst. Reactions were carried out at 150°C or 160°C without solvents. In the later period of the reaction, it proceed as a second-order reaction, and p/(1-p)-t plot agreed straight line. Gelation point was determined by extrapolate of this line to gel time.
Estimated extent of reaction at gel point using above equation were agreed with results of experiments very well. Standard deviation of Δp=P_obs.-P_calc. was 3.8%.

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p-Methoxystyrene and isobutyl vinyl ether have been polymerized by using iodine as a catalyst. Monomer transfer constant (k_tm) and apparent unimolecular transfer or termination constant (k_t′) were determined in carbon tetrachloride and ethylene chloride solution. Results were summarized as follows; 1) k_tm and k_t′ as well as k_p increased with increasing polarity of the solvent. 2) Monomer with strong electron-donating groups showed large k_tm and k_p. 3) With strong Lewis acid catalyst, k_p and ktm increased. 4) The activation energy of k_p and k_tm, using iodine catalyst was smaller than that using sulfuric acid catalyst. These results indicate that monomer transfer in cationic polymerization using iodine is similar to that using conventional metal halides. The abstraction of proton from a growing chain end is more important than recombination of the growing chain with the counter anion for the reaction related to k_t'.

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Cyclopentadiene has been polymerized in toluene by using TiCl₄-CCl₃CO₂H initiator at 78°C. The polymerization stopped at a constant conversion, which could be determined byconcentrations of monomer and initiator. At a constant initiator concentration, the final conversion increased with decreasing the initial monomer concentration. The final conversion increased when the concentration of trichloroacetic acid as a cocatalyst increased. When monomer or cocatalyst was introduced into the “dormant” polymerization system containing unreacted monomer, the conversion did not increase. However, when TiCl₄ was added to this system more polymerization occurred. These results could be explained by assuming the formation of unreactive material from one molecule of catalyst with two molecules of monomer.
It has also been established that the final conversion decreased with increasing water concentration. These data have shown that water had two effects, i.e., deactivation of the catalyst and deactivation of the growing chain end.

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In order to clarify the mechanism of the radiation-induced solid state polymerization of vinyl monomers, the binary systems containing acrylic monomers and crotonic acid were investigated.
These systems form an eutectic mixture in the solid state and the polymerization rate of acrylic monomer is accelerated in the presence of the another component, although the rate in the liquid phase is retarded.
The polymerization rates in solid-liquid equilibrium phase show the both characters of solid and liquid phases and have a maximum peak at a certain monomer composition.
It is recognized that the degree of polymerization is decreased and the gel formation from acrylic polymer is almost inhibited in the solid state polymerization of these systems.
Such experimental results suggest that certain accelerative effect of polymerization based on the crystal structure is in existence and chemical interaction such as chain transfer is also effective in the solid state polymerization of the eutectic mixture systems.

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A Mannichb ase, preparedb y the reactiono f 2-hydroxy-5-methaycle tophenon (eII I) with dimethyalm inea nd formaldehydwe, a sp yrolyzedto give 2-hydroxy-5-methyl-phevninyyl l ketone (OVM). Severalp olymersc ontaininga n o-hydroxyk etones tructure were obtained by the thermapl olymerizatin of OVM and by the radical copolymerizations of OVM with styrene, methylmethacrylanted cresyla crylate (CA).
For the UV light induced Fries rearrangement of polycresyal crylate (PCA) reported in the preceeding paper, the retarding effect of these substances were examined. Blending of model compound (III) or the homopolymer of OVM up to 20% had no effect on the photochemical transformation of a phenylester group of PCA to an o-hydroxyketone group.
While the incorporation of o-hydroxyketone unit in the PCA molecule as a comonomer over 25% exhibited an enhanced stabilization and improved permanence and the complete inhibition of the rearrangemenotf PCA was attained. A preliminary test, areplacement of an H atom of the hydroxyg roup in CA-OVM copolymer by Al or Ni atom, failed to increase the stabilizing power of the o-hydroxyketone structure. All of the above methods (blending and copolymerization of o-hydroxya cetophenone unit) were unable to stabilize polystyrene against photo-oxidation.

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