Electrocoagulated poly (butyl methacrylate) latices of various particle sizes were immersed in water and the film formation was investigated. It was found that wet sintering effect is significant at the beginning of the coalescence of the particles and the degree of the coalescence is affected by the particle size of the latex. The values of aη obtained by applying Laplace's theory were compared for each latex and the mechanism for the film formation in water was discussed.
Film formation in dry oven was also examined. It was inferred that wet sinteriong strongly affected the film formation process under this condition, too.

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The structure of films obtaind from the emulsifier-free ethyl acrylate-methyl methacrylate copolymer (I) emulsion, was investigated by measuring the water flux, water-absorbing capacity and also by the scanning electron microscopy. The rejection of monodisperse polystyrene emulsion particles (II) (diameter, 0.091 μm) decreased with the increase of water flux. Films of I casted from the benzene solution showed no water flux and no penetration of II. As the content of ethyl acrylate unit in I increased, the water flux and water absorbing capacity increased. The water flux from the air side of the film in the formation process was about 36 times of that from the supporting plate (glass) side. In the rate of water absorption, the similar difference was acknowledged in regard to the absorption direction. It is observed by the scanning electron, microscopy that the air side is more porous than the glass side.
From these results, it is concluded that the emulsifier-free emulsion films of I are consisted of asymmetrical porous structure.

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The photo-induced graft polymerization onto 2, 3-dialdehyde cellulose was carried out in a quartz tube. The initial rate of grafting decreased in the order of methyl acrylate, methyl methacrylate, vinyl acetate, acrylonitrile and styrene, and the graft efficiency was 70-98% except for a quite low value of vinyl acetate. The degree of grafting in the graft polymerization of styrene and acrylonitrile increased with the monomer concentration. The degree of grafting and the apparent number of grafted chains increased and grafted chain length decreased, with increasing the carbonyl content in cellulose. The larger apparent number of grafted acrylonitrile chains obtained in a quartz tube than that obtained in a pyrex tube showed that the graft polymerization in a pyrex tube proceeds mainly via the photolyses of carbonyl groups in cellulose by the light longer than 300 nm. On irradiation with the light of 253 nm in a quartz tube, however, grafting onto the end group, due to the chain scission of cellulose molecule, concurrently occured. Termination proceeds by the coupling between the growing polymer radical and the cellulose radical.

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The present author previously reported on the reverse osmosis by poly (styrene-b-acrylic acid) membrane. In the present paper, we report that the photosensitive hydrophilic polymer obtained by copolymerization of 4-methacryloyloxychalcone with N, N-dimethyl amonoethyl methacrylate is used as reverse osmosis membrane by photocrosslinking the thin layer coated on microporous polypropylene support membrane. Salt rejection, flux and water content of the membrane are affected by the content of the crosslinker, 4-methacryloyloxychalcone, in the copolymer. With the composite membrane prepared from the low molecular weight polymer and the support, salt rejection proceeds according to the diffusion mechanism in accordance with Yasuda or Lonsdale equation.

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The flocculation of kaolin suspensions in the aqueous solutions of purified polyacrylamide (PAAm) of various molecular weights was measured at various polymer concentrations by the turbidity of the supernatant liquid. In the range of molecular weight of PAAm smaller than 3×10⁶, the ratio of the optimum polymer concentration for the flocculation to the molecular weight of polymer was found to be nearly constant. If the flocculant is the mixture of PAAm having different molecular weights, the flocculation is mainly governed by the component of the higher molecular weight. Especially if the polymer concentration is lower than the optimum concentration, the lower molecular weight component is almost inert for the turbidity of the supernatant. Also, the stability of PAAm itself was studied in terms of viscosity change with time. Concentrated aqueous solutions of high-molecularweight raw PAAm showed instability. With the purification by dialysis, the PAAm was stabilized even at 0.2%, as indicated by the constant viscosity after one week.

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Polymerization and copolymerization of 1, 1′-bis (methoxycarbonyl) divinylamine (BDA) were studied. BDA polymerized with radical and cationic catalysts but not with an anionic catalyst. BDA did not copolymerize with some monomers such as, MMA or butyl vinyl ether at steady state, but inhibited the radical polymerization of styrene or MMA. No gel product was found in the BDA-polymer obtained by radical polymerization, and the polymer was suggested to be consisted of mainly 9-membered bicyclic ring structure (IV) as a result of cyclopolymerization.

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An analytical method to obtain the IR spectra corresponding the 1st and the 2nd layers of laminated polymer films was studied by use of a Fourier transform infrared spectrometer combined with ATR attachment. In the present case, the thickness of the 1st layer was thinner than infrared wave lengths used. Two different spectra (a and b) of the samples were measured for the two incident angles. For arithmetic operation, the key band of each layer was selected by comparing the relative band intensities of both a and b spectra. If possible, the key bands were desired to be strong and symmetric in shape and not to be overlapped with any of another layer's bands. The spectra of both layers were separately obtained by taking the difference between a and b spectra. The factors for the computation were calculated by the peak intensity ratio of the key bands of a and b spectra. By this method, the spectra of the 1st and the 2nd layer were preferably obtained for the samples of surface coated poly (vinyl alcohol) and polypropylene films.

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The polymerization of methacrylic acid (MAA) was carried out in the presence of chitosan (CS) using potassium persulfate as an initiator in water, and the optical activity and stereoregularity of the resulting polymeric MAA were investigated. Mixtures for the polymerization were prepared by mixing of an aqueous solution of CS containing equimolar amount of acetic acid with an aqueous solution of sodium salt of MAA.
The resulting polymeric MAA, and its methyl ester had optical activity opposite (+) to that of CS used as matrix, even after the removal of CS by hydrolysis with concd. HCl, followed by oxidation with sodium metaperiodate. The isotactic content of the methyl ester of the polymeric MAA obtained in the presence of CS was larger than that obtained in its absence, and the triad tacticity deviated from a Bernollian statistics. The optical activity of polymeric MAA and its methyl ester prepared in the presence of CS was proposed to come from the polymer chain.

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For the continuous production of high-modulus polyethylene, the effects of the drawing in solid state after the elongational flow-induced extrusion and of the subsequent annealing on the crystallinity, the orientation and the tensile modulus were investigated.
The modulus of the flow-induced polyethylene was increased by the subsequent solid-drawing and annealing. The modulus reached 32 GPa.
The increase in the modulus may be attributed mainly to the orientation during the solid-drawing and annealing, and probably to the growth of the extended-chain crystals which may be formed during the elongational flow.
The suitable molecular weight distribution and the optimum combination of the conditions of the extrusion, the solid-drawing and the annealing may further increase the crystallinity and consequently the modulus.

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The epoxidation of polybutadiene with a peracid produced by the reaction between a hydrogen peroxide and an aliphatic acid in the epoxidation medium, “in situ peracid reaction”, was investigated. The amount of the epoxidized unit was determined by ¹H NMR spectrometry and by measuring the epoxy value of the resulting polymer. The reaction with formic acid was rapid even in the absence of a strong acid catalyst, although its addition was necessary for the reaction with acetic acid to proceed smoothly. The ring opening of the epoxy unit of the resulting polymer (hydroxylation reaction) could be successfully avoided by using small amounts of formic acid. The epoxidation rate depended on the polymer microstructure in the order of cis-1, 4-polybutadiene>liquid equibinary (cis-1, 4-1, 2) polybutadiene>liquid 1, 2-polybutadiene. The higher reactivity of 1, 4-unit, as compared to 1, 2-unit, was also confirmed by carbon-13 NMR spectrometry of the partially reacted polymers.

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