The molecuar weight distribution of polyvinyl chloride (PVC1) samples has been studied by the column fractionation. The molecular weight distribution function obtained by this method has been compared with the results of the fractional precipition and ultracentrifuge methods. It was found that this method gives the highestM_w/M_n value. Thereliability of this method has been confirmed by the agreement between the observed value of intrinsic viscosity [η] and the value calculated from the molecular weight distribution obtained.

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Optical birefringence (Δ) and tear resistance of tubular polyethylene films extruded under various conditions were measured. The results is as follows:(1) The value of Δ increases as the blow-up ratio decreases or the haul-off speed increases and a linear relationship between Δ and ψ₁₁₀ is presented. With the aid of this relationship, Δ at ψ₁₁₀=34°C (corresponding to the perfectly oriented Keller's type II) is evaluated as 9×10^-8 by extrapolation, which nearly coincides with the theoretical value, 14.5×10^-3.
This suggests that the orientation in most tubular polyethylene film is Keller's type II.
(2) The mesurement of retardation along the direction of thickness of the film indicates the non-uniformity of the crystalline orientation in the plane perpendicular to the machine direction.
(3) From the temperature dependence of the tear resistance of films and the relation between the direction of tear and that of crystalline orientation it may be concluded that the crystalline regions form the layyers parallel to the plane perpendicular to the machine direction and the amorphous regions are sandwitched between them.

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Behevior of HCN in the Nieuwland's catalyst has been studied. When C₂H₂ and HCN are passed through the catalyst solution containing CuCl and NaCl, total amount of acrylonitrile (AN), HCN evolved, and nitrogen compound in the catalyst are equivalent to HCN supplied. When supply of HCN is stopped after passing C₂H₂ and HCN into the catalyst solution for a some time, AN formation still continues for a long time. When a difinite amount of liquid HCN is added previously to the catalyst solution and C₂H₂ is passed at the reaction temperature of 90° C, only loss of HCN occurs at first stage of reaction, and after a certain induction period AN formation occurs, the formation rate of AN decrease gradually corresponding to the decrease of HCN concentration in the catalyst. On the contrary formation rate of acetylene polymer increase corresponding to the decrease of that of AN. However, total sum of the rate of all products is not changed during this reaction. Instead of HCN, the CuCN and HCl of equivalent amount to HCN are used, the mode of this reaction is not changed at all. Hence it has been considered that HCN supplied Nieuwland's catalyst changes to CuCN and HCl in the Newland's catalyst.

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Gamma-ray induced effects have been studied on the mixtures of two different water soluble polymers, i. e. polyvinylalcohol, polyvinylpyrrolidone, polyacrylamide, methyl cellulose and polymethacrylic acid, in aqueous solutions in which the individual polymer is disolved below a critical concentration for gelation. It was found that networks between two different polymer components (co-network) was built up if both polymers were crosslinking type, and, on the contrary, gel formation was retarded if one of two polymers was degradative-type. Co-crosslinking occurred at the system of polyvinylalcohol-polyvinylpyrrolidone was examined by the measurements of the viscosity of irradiated solutions and the solubliity of irradiated polymers in methanol. It has been that observed there is linear relationship between the gelation dose for the mixture of two polymers, i. e. polyvinylalcohol-polyvinylpyrrolidone or-polyacrylamide, and the content of the mixture. The network formation of crosslinking-type polymers in their aqueous solution was retarded by the presence of methyl cellulose. General mechanism for co-crosslinking of these polymers in aqueous solution has been briefly discussed.

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Copolymerization of styrene with 2-methyl-5-vinyl pyridine was carried out by Al (C₂H₅)₈-TiC1₄, catalyst system at the Al/Ti mole ratio of 2.5: 1 and at 70°C. In order to compare with this catalyst system, copolymerization by azo-bis-isobutyronitrile initiator and Na catalyst was also carried out. The monomer reactivity ratios were obtained as follows:γ_st (±0.1), γ_mvp=2.9 (±0.3), γ_stγ_mvp=1.45 (ALEt₃-TiCl₄),
γ_st=0.60 (±0.1), γ_mvp=0.68 (±0.1), γst_mvp=0.41 (AZN)
γ_st=0.3 (±0.1), γ_mvp=2.9 (±0.3), γst_mvp=0.87 (Na)
These results indicate that the copolymerization by Al (C₂H₅) ₃-TiCl₄ is anionic. Solubility in methyl ethyl ketone, infrared absorption spectrum and X-ray diffraction pattern were measured on this copolymer. From these experimental results, it may be concluded that the isotactic regular sequence of 30-40 styrene units is necessary in order that this copolymer exhibits the characteristic properties of isotactic polystyrene.

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To improve the dye affinity of acrylic fiber, partially saponified acrylate polymers, HNO₃treated polyacrylonitrile (PAN) and polymethyl acrylate were mixed with PAN. Solutions of PAN containing up to 4% of the other component are stable and give filaments homogeneous in the fine texture. The spinnability of these solutions was generally inferior to that of PAN solution. The equivalent number of acid group for these filaments become larger by mixing, but it decreased by treating with boiling water, excluding the case of the mixture of PAN and HNO₃ treated PAN.

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In copolymerization of acrylonitrile (AN)-vinyl acetate and AN-2-methyl-5-vinyl pyridine in batch process more reactive monomer was added continuously by the amount calculrted by Hanna's method using monomer reactive ratio. The copolymer obtained has chemically uniform composition.

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