In preparing acrylonitrile-vinyl acetate copolymer (93: 7 in weight) by continuous polymerization using a complete mixing type reactor in the presence of persulfate and bisulfite initaitor, effects of electrolyte on physical properites of the resulting polymer were studied by varying the concentration of electrolyte in polymerization medium under the condition of low water to monomer ratio. The following results were obtained.
(1) Good correlations between ionic strength of polymerization medium and either dewatering property of the polymer slurry or bulk density of the polymer have been observed at each level of water/monomer ratio.
(2) Zeta potential of polymer particles prepared under the condition of water/monomer ratio 2.0 from the reactor slurry are approximately from -30 mV to -70 mV depending either on pH in the range from 3 to 5 or on concentration of Na₂SO₄ below 0.01 mol/l as an electrolyte in medium.
(3) The correlation of the item (1) might be approximately explained by the modified application of the existing equation based on DLVO theory.

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Cationic oligomerization of α-methylstyrene (MST) was carried out at 0-120°C with homologous protonic acids, that is, mono- (MCA), di- (DCA) and trichloroacetic acids (TCA) as an initiator with or without solvent.
Monomeric telomers accompanied with a counteranion were obtained in the MST-MCA and MST-DCA systems. These adducts were liable to revert to the monomeric carbocation, which was led to the dimeric carbo- cation through the addition of MST. The all systems were found to involve depolymerization and isomerization reactions of the oligomers. The decrease of the nucleophilicity of the counteranion promoted the interconver- sion between dimer and trimer, and the isomerization of 4-methyl-2, 4-diphenyl-1-pentene to -2-pentene, followed by 1, 3, 3-trimethy1-1-phenylindane. On the other hand, the interaction between the growing carbocation and the counteranion was weakened by solvation in nitromethane at 0°C, and higher molecular oligomers were formed by preferentially addition of MST to the growing carbocation.

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The synthsis of ferrocene-poly (vinylamine) (Fc-PVAm) complex was carried out under various contents of ferrocene. The Fc-PVAm (content of Fc = 7.6 mol %) complex was dissolved in mixed solvents of acetone and aqueous solution, and was investigated using potentimetory, visible spectroscopy, and others. These experiments indicated that new mixed metal complexes having both [Cu (N) ₄] and Fc structures were formed when the ratio of free amio residue to copper ion was larger than 5.

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The chemical reactivity and the viscoelastic properties of the epoxide blends containing the intermolecular compound of 2, 4-diamino-6-vinyl-s-triazine (1) and isocyanuric acid were studied using a differential thermal analysis and a torsional braid analysis. The intermolecular compounds of 2, 4-diamino-6-ethyl-s-triazine (2) or melamine and isocyanuric acid were used as the reference of (1). The epoxide blend containing the intermolecular compound of (1) and isocyanuric acid in the presence of imidazole compound cured rapidly than that of the intermolecular compound of (2) or melamine. But, the glass transition temperatures (T_g) of their cured blends were almost equal. The T_g value of the cured epoxide blends containing the intermolecular compound of (2) and isocyanuric acid is higher than that of the cured epoxide blend containing (2). The raise of T_g appeared due to the reaction of isocyanuric acid and epoxide.

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Deformation of poly (ethylene terephthalate) film was carried out by means of a roller-drawing method. An amorphous film could be drawn to a draw ratio up to 5.3 at 80°C. The effect of draw ratio on the mechanical properties and the structure of roller-drawn strips was investigated. With increasing draw ratio, tensile strength and modulus of elasticity increased. The improvement of mechanical properties of poly (ethylene terephthalate) film by roller-drawing is considered to be due to an increase in chain orientation and to the orientation-induced crystallization. The preferred orientation of crystallographic axes of roller-drawn strips was clarified by the measurements of wide-angle X-ray diffraction. The 100 pole of the heavily roller-drawn and heat-treated strip (λ= 4.0) was distributed in the direction normal to the film plane.

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Acrylic acid (AA) and acrylamide (AAm) were graft-copolymerized onto polyethylnene (PE) powder by the preirradiation method. Complex formation constants of Sm ion with the PE powder grafted with both AA and AAm (PE-g- (AA-co-AAm)) were larger than those with the PE powder grafted with AA (PE-g-AA). Sm ion was efficiently separated from the solution containing both Sm ion and a transition metal ion such as Cu ion. Even after the γ-ray irradiation on PE-g- (AA-co-AAm) and PE-g-AA, the adsorption did not decrease.

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The phase diagram of Flory's equation of state were studied by computer simulation. The diagrams under p=0 or p≠0 could be well understood from the usual standopint. But the prediction of the two liquid phase equilibrium was not supported. The result that either ε* or v* should be positive was not found.

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An investigation has been made of the relation between void volume and tensile modulus of oriented polypropylene filled with surface modified calcium carbonate. The modifiers are phosphate ester, titanate coupling agent and stearic acid. The void volumes of surface modified filler systems are smaller than those of unmodified ones, irrespective of filler size and filler content. The relative modulus of oriented composites, E_c^d/E_r^d (wherein E_c^d, E_r^d are modulus of oriented composites and modulus of oriented polymer matrix, respectively, ) can be simply expressed as a function of void volume formed by drawing, irrespective of modifiers.

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Polymer-coated porous particles containing aspirin as a drug were prepared and the release of rate of aspirin was studied. The impregnation of aspirin was carried out by post-graft polymerization, where methyl methacrylate containing aspirin was treated with porous particles including iron oxide, preirradiated with γ-ray form Co-60. Release of aspirin from modified particles was examined with 50% methanol solution. The amount of aspirin absorbed in porous particles increased by grafting of methyl methacrylate. The particles treated with iron hydrous oxide sols before irradiation led to the increment of aspirin absorption. Diffusion of aspirin through the polymer matrix and the gelled layer was the limiting process in the aspirin release from particles. The rate of aspirin released from modified particles including iron hydrous oxide wasn't affected by the grafting of methyl methacrylate.

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N-Alkylated polyallylamines were synthesized by the reaction of various alkyl bromides with polyallylamine (PAA) and their catalytic effects on the hydrolysis of p-nitrophenyl esters were investigated. The catalytic effect of PAA, which was higher than polyethyleneimine, was increased by N-alkylation. Higher catalytic effect was revealed on the introduction of longer alkyl chain. With the hydrolysis of phenyl esters having alkyl chains of different length, the catalytic effect of PAA decreased with an increase in alkyl chain length but catalytic activity of N-octylated PAA showed the maximum for the ester of middle alkyl chain length (p-nitrophenyl hexanoate).

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