Aqueous solutions of maleic anhydride-styrene (A), -vinyl acetate (B) and -vinyl benzoate (C) copolymers having nearly alternative structures were potentiometrically and conductometrically titrated with some bases. The order of pH values was C>A>B at the low degree of neutralization, but was A>B≈C at the high degree of neutralization. Titration curves of A showed the more significant inflection near the half neutralization point compared with those of B and C. The order of conductivity was B>A>C at the low degree of neutralization, but was A>B≈C at the high degree of neutralization. At low degree of neutralization the values of η_sp/c of B were much higher than those of A and C, but at middle degree of neutralization the three copolymers showed comparable values of η_sp/c. Addition of npropanol increased considerably values of η_sp/c of C at low degree of neutralization. From the results, it seems that the higher values of pH of C at low degree of neutralization may be mainly attributable to tighter coiling of the chain molecules, and the higher values of pH of A at high degree of neutralization may be mainly due to nearer approach of two carboxylic groups in the same maleic anhydride unit.

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The aqueous solutions of copolymers of maleic anhydride and methyl acrylate (-MA), methyl methacrylate (-MMA), acrylonitrile (-AN), vinyl pyrrolidone (-VP) and isobutyl vinyl ether (-VE) having nearly alternative structures were potentiometrically and conductometrically titrated with NaOH. The order of pH was -VE>-AN≈-VP≈-MA>-MMA at the low degree of neutralization, but was -VE>-MMA≈-VP>-MA>-AN at the high degree of neutralization. The order of conductivity was -MMA>-MA≈-VP--AN>-VE at the low degree of neutralization, but was -VE>-MMA≈-VP>-MA>-AN at the high degree of neutralization. With increasing degree of neutralization, viscosity of -VP increased more greatly than those of the other copolymers. From the present and previously reported results, it seems that the higher value of pH of -VE at the low degree of neutrarization is mainly attributable to tighter coiling of the chain molecule arising from hydrophobic interaction between vinyl ether units, and the higher values of pH of -VE, -VP and -MMA at the high degree of neutrarization are mainly due to the nearer approach of two carboxyl groups in the same maleic anhydride unit resulting from the steric effects of side chains of the neighboring comonomers.

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Following the treatment of Kamide and Kawai (J. Chem. High Polymer, Japan, 20, 512 (1963)), theoretical relationships between the parameters K_m and a in the Mark-Houwink equation [r]=K_mM^a have been derived by the use of the treatments of Flory and Fox (FF), Kurata and Yamakawa (KY) and Fixman (Fi). Combination of the FF and Fi treatments leads to:
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and of the KY and Fi treatments to:
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where K is the Flory constant and M₀ a parameter of the molecular weight range for which the values of K_m and a apply. Experimental data for poly (methyl methacrylate), polystyrene, poly (vinyl acetate), atactic polypropylene and isotactic polypropylene are in good agreement with these relationships which also provide a means of evaluating K from values of K_m and a for good solvents.
The relationships are not, however, applicable to cellulose derivatives. For these, deviations of values predicted by theoretical treatments or combinations of them from those obtainedexperimentally follow the order: FF>KY-KSR>KY-Fi>FF-KSR>FF-Fi where KSR refers to the treatment of Kurata, Stockmayer and Roig.
It is shown that d log K_M/da><0 for a><a^* where a^* is the value of a at d log K_M/da=0 and depends on M₀ but not on K. Since no experimental data have shown d log K_M/da to be greater than zero, the treatments considered may only apply, at best, to cases where 0.5<a<a^*. Because of this, the Flory-Fox treatment, even if a<0.8, cannot interpret the experimentaldata in terms of only volume effects and, even if a<1.0, the Kurata-Stockmayer and Stookmayer-Fixman treatments may be inapplicable in certain cases.

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An attempt has been made to reproduce the broadening of viscoelastic dispersion observed for polyblends, copolymers and plasticized systems by the ladder model.
Two different values were assigned to restrictive forces from surrounding media in a model. It was found that the peaks of tan ?Aand loss compliance move from one to another on the time axis taking a minimum value in the range of intermediate composition, when the effect of existence ratio of component units was assumed to appear through a relative difference between the two values of restrictive forces.
The same tendency was also found for a continuous distribution instead of two discrete values of restrictive forces. It can be concluded, from these results, that the possible cause of the broadening of viscoelastic dispersion is an inhomogeneity of segmental mobility over a space comparable with that occupied by the molecular chain between coupling points.

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The contribution of the draining effect to dilute solution properties of cellulose trinitrate is obtained from an analysis of sedimentation constant-molecular weight and sedimentation constant-concentration relationships. The results are compared with those obtained in the previous paper (J. Chem. High Polymers, Japan, 21, 1 (1964)) in which molecular constants were evaluated by use of the treatment by Kamide et al. of intrinsic viscosity-molecular weight relationships (J. Chem. High Polymers, Japan, 20, 512 (1963)). Values of the parameter Δ, expressing the magnitude of the draining effect, are in good agreement and giveΔ =0.3-0.4. The value of the excluded volume parameter ε (ε=dln α/d In M, where a is the expansion factor and M the molecular weight) is 0.06-0.08, in acetone and ethyl acetate. The treatments of Kurata-Stockmayer and Stockmayer-Fixman cannot account for experimental data for cellulose trinitrate in acetone and ethyl acetate.

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A study of radical or cationic polymerization of glycidyl methacrylate (GMA) has been made. In its radical polymerization at the monomer concentration more than 5.46 mol/l in benzene, the gel effect was observed at a low conversion below 12% and the resulting polymer was insoluble in any organic solvents. However, at the monomer concentration of 3.78 mol/l, the gel effect was not appeared up to about 35% conversion. From the determination of the epoxy content in the polymer and the kinetic investigation, it was found that only a vinyl group in GMA participated in its radical polymerization and the observed rate equation followed to the ordinary rate equation in radical polymerization. Since the intrinsic viscosity and Huggins' k′ constant of the resulting polymers increased as a function of the polymerization time, it was suggested that the formrition of branched polymer would lead to an insoluble polymer with time in radical polymerization of GMA.
In cationic polymerization of GMA catalyzed by BF₃EOEt₂, only a epoxy group participated in its polymerization and the cyclopolymerization of GMA which was pointed by Arbuzova et al was not occured.

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Radiation vulcanization of natural rubber in solution was studied. Natural rubbers dissolved in various solvents were irradiated by γ-rays from Co⁶⁰ in vacuum and swelling ratios were measured to obtain the degree of vulcanization.
Rate of vulcanization was fast in the solvent which has large G-value of radical formation and radical scavengers, such as DPPH and nitrobenzene, inhibited or retarded the vulcanization. It was concluded, therefore, that the vulcanization in this system was due to the indirect radical mechanism.
Kinetic studies showed that the rate of vulcanization was proportional to the square root of radiation dose rate and was proportional to the rubber concentration in the low concentration range or independent of the concentration in high concentration range. The experimental results show good agreement with the above theoretical results. Effects of irradiation temperature were also studied and as an apparrent activation energy, 6.8kcal/mol was obtained.

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The mechanical degradation of PVAc resulted from a violent stirring of that solution has been studied. Degree of polymerization of PVAc and its hydrolyzed polymers, before and after the degradation, has been determined. From these data, it was found that the chain scission did not occured at C-C linkage, but did at ester linkage on branched point. The less the solution concentration, the poorer the solvent power and the higher the rate of shear, the more the degradation was.

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