The interactions of polyurethanes containing dulcitol (DPU) with some metal ions such as Cu²⁺, Ni²⁺, Mn²⁺ and Co²⁺ were investigated in dimethylsulfoxide (DMSO) -water system. The results obtained were as follows: a) The complexation between DPU and Du²⁺ occurred in pH 6.8-8.0, where ionic strength and anion showed negligible effects on complexation. b) The values of the dissociation constant pK_a and the constant n for DPU were estimated to be 15.3 and 2.37, respectively, by use of a modified Henderson-Hasselbalch eqaution. c) The stability of DPU-Me (II) complex formation increased in the following order Cu²⁺>Ni²⁺>Co²⁺> Mn²⁺, which obeyed Miller-Maley order and Irving-Williams order.

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For thermosetting resin containing nitrile rubber, the optimal composition and the surface finishing condition were searched to obtain strongly adhesive and heat resistant plated plastics. The resin composed of nitrile rubber, phenolic novolak, solid epoxy resin and zinc oxide provided the peeling strength of 6.8kg/cm and solder heat resistance over 600sec at 260°C. The chemical etching with potassium bichromate and the mechanical roughening by liquid horning were examined for the resin surface roughening. The former method provided finely roughened surface and the latter also gave satisfactory roughening. The adhesive strength depended on the blending ratio and compatibility of nitrile rubber and thermosetting resin, the amount of zinc oxide, the thickness of resin film and the roughened surface state. The heat resistance was influenced by the resin thermal stability, the amount of plating catalyst and the adhesive strength.

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The popcorn polymer (PCP) of 3, 5-dimethylstyrene (DMS), insoluble in solvents investigated (e. g., benzene, toluene, tetrahydrofuran, and 1, 4-dioxane), was formed in the temperature range 30 to 40°C. The popcorn copolymerization of DMS with methyl acrylate and styrene occurred over the whole range of monomer composition in feed at 30°C, whereas the popcorn copolymerization of DMS with metyl methacrylate occurred only at the mole fraction of methyl methacrylate in feed smaller than 0.3. The composition of popcorn copolymer was almost identical with that of monomer in feed, indicating that the popcorn copolymerization proceeded without the selection of monomer. The composition curves of the copolymer soluble in benzene, which was fbrmed simultaneously with PCP, were in good agreement with those of the conventional redical copolymerization. The composition of first developed particle of DMS-PCP differed from those of both the above popcorn and copolymers.

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The solid state film extrusion of poly (1-butene) was carried out under 2500 atm at 100°C. Extrudates with smooth surfaces were not produced from unoriented pristine samples but successfully obtained by using the preoriented sample (draw ratio=1.5) as a starting material and by pulling the film extruded at the exit of high pressure die. Films thus obtained were flexible and transparent. X-ray diffraction studies of the extrudates have been made to determine the selective orientation of form I crystals. The extruded films show the double orientation with the c-axis preferentially oriented to the machine direction and with the a-axis parallel to the film surface. This selective orientation was explained by assuming that the (300) plane of a form I crystal preferentially glides upon the extrusion.

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In order to find the change in the chemical structure of the polymer and the role of chlorine atom in the polymer for raidation stability, the radiation-induced gas evolution of chrorinated polyethylene, chrorinated and hydrochlorinated poly (1, 4-cis-isoprene) was measured. The chlorination of polyethylene brought about an increase in the radiation stability. While the stability decreased over 30% of chlorine substitutions. The chlorination and hydrochlorination of poly (1, 4-cis-isoprene) reduced monotonously the radiation stability. With the chlorinated and hydrochlorinated poly (1, 4-cis-isoprene) at the same chlorine substitution, the former gave lower gas evolution than the latter. This rubber hydrochloride showed relatively low gas evolution by the self absorption of evolved gas, but was found to be relatively unstable against radiation.

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The effect of poly (vinylpyrrolidone) (PVP) has been studied for the reactions of substrate A; 2, 4-dinitrochlorabenzene, 2, 4-dinitrofluorobenzene or p-nitrophenyl caproate with nucleopile B; OH^-, ammonia, 3-amina1-propanol, ∈-amino-n-caproic acid or β-mercaptopropionic acid (MPA), and for the hydrolysis of aspirin and p-nitrophenyl phosphate (PNPP). PVC accelerates the reactions of each substrate A with OH^-, ammonia or amino compounds and the alkaline hydrolysis of aspirin, but has no effect on the reactions of the substrates A with MAP and the monomolecular hydrolysis of aspirin or PNPP. It is suggested that the rate of the reaction between two substrates A and B is enahnced when both A and B are absorbed on the PVP chains, but that it is not enhanced when either substrate is not adsorbed. In the monomolecular reaction, even when PVP adsorbs the single substrate, the reaction is not necessarily enhanced, unless the reactivity of substrate is activated by the adsorption.

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An apparatus newly constructed for measurements of permeation on mixtures of gases and vapors through polymer films is described. The apparatus utilizes the carrier gas method, instead of the conventional pressure method, with gas-chromatographic analysis to determine the individual transport characteristics of component gases. At pressures below an atmospheric pressure the gaseous mixture is supplied to the upstream side of the polymer film by the circulating method, while at pressures above an atmospheric pressure by the flow method. Measurements may be performed in the region of -30 to 150°C and up to 6 atm feed pressure. Permeability coefficients P of several gases in a styrene-butadiene block copolymer film which has a domain structure of an alternating lamellar type were measured employing helium as a carrier gas. The average errors in determining P were 4% for N₂ and O₂, and 2% for other gases. The transport data, including apparent activation energies for permeation and diffusion, for Ar, Kr, and N₂ obtained with the present apparatus showed good agreement with those obtained with the conventional vacuum-type apparatus.

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The effect of the distribution of carboxyl group in polymer emulsion particles consisting of methyl methacrylate, ethyl acrylate and methacrylic acid on its alkali thickening and film forming abilities was studied. Three types (A, B and C) of emulsions with the same polymer component were prepared and compared each other: A, the whole amount of the monomer mixture were added initially; B and C, the monomer mixture were portionwisely added at regular interval. In case of B, the concentration of methacrylic acid in each portion was decreased gradulally, and in case of C, it was increased. The relative concentration of carboxyl group at the surface layer of the particles were the molar ratio of methyl methacrylate, ethyl acrylate and methacrylic acid was 63/27/10, increased in the order, C>B>A. The alkali thickening and film forming abilities fell in the order, C>B>A. From these results, it was clarified that the distribution of carboxyl group in particles affected the alkali thickening and film forming abilities.

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