α-Amylase was chemically bonded to a gel consisted of polyacrylamide (PAA) and dialdehyde starch (DAS) and its properties have been investigated. The enzymic activity of the immobilized α-amylase (IE) gel was determined by measuring the absorbance at 700 nm of solutions containing IE gel, a substrate, and KI-I₂, being quite remarkable for the hydrolysis of starch at 40°C; the wet IE gel with a component ratio of 1: 1 showed an activity per unit weight corresponding to 0.024 mg of native α-amylase (NE). The wet gel, which was composed of networks of loosely cross-linked polymer and swelled with water, contained more than 98% of water. Thermal stability on the activity of the IE gel was superior to that of the NE in the range of 20-70°C at pH 7, although no apparent difference was observed between the activities of IE and NE in the range of pH 3-7 at 40°C. The Michaelis-Menten constant (K_m) and maximal reaction rate (V_max) of IE were estimated to be slightly larger than those of the NE. The enzymatic activities of the IE gel for starch hydrolysis were discussed in detail.

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Photosensitive polymer with a pendant styryl methyl ketone (4- (2-acetyl) vinylphenyl) group was prepared by the radical polymerization of 3-methoxy-4-methacryloyloxy styryl methyl ketone (3MeO·4MS). The monomer was synthesized by the esterification of 3-methoxy-4-hydroxystyryl methyl ketone with methacryloyl chloride. Radical polymerization was carried out in tetrahydrofuran at 60°C. The polymerization occurred at the methacryloyl group without affecting the styryl methyl ketone group to yield linear polymers in high yield. Poly (3MeO·4MS) film was effectively crosslinked by the irradiation of UV light. The relative photosensitivity of the polymer (S) was correlated to the degree of polymerization (M_w) by the following equation:
S=6.7M_w
The 3MeO·4MS-methacrylic acid copolymer was soluble in an aqueous alkaline solution and can be utilized as a water-soluble photoresist.

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2-Anilino-4- (nitroanilino) -6-isopropenyl-1, 3, 5-triazines ([1]; p-substituent, [2]; m-substituent) were prepared from the reaction of N¹-phenyl-N⁵- (nitrophenyl) biguanide with methacryloyl chloride. 2-Anilino-4- (aminoanilino) -6-isopropenyl-1, 3, 5-triazines ([3]; p-substituent, [4]; m-substituent) were obtained by the reduction of [1] and [2] using iron powder and ferrous sulfate. 2-Anilino-4- (3-phenylureido) anilino-6-isopropenyl-1, 3, 5-triazines were prepared by the reaction of [3] and [4] with phenyl isocyanate. The homopolymerization and copolymerization with styrene (M₁) of these monomers (M₂) were carried out in dimethyl sulfoxide at 60°C using azobisisobutyronitrile as an initiator. The copolymerization parameters (r₁, r₂, Q and e) were determined for these monomers. It was found that the effect of substituent of isopropenyltriazines [1] - [4] on 1/r₁ followed Hammett's equation and ρ value was given as +0.14.

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In the stereospecific polymerization of propylene with an Et₂AlCl-TiCl₃ catalyst, the addition of hexamethylphosphoric triamide (HPT) to the catalyst system was found to activate the catalyst without detriment to the stereoregulation of the polymerization. It was presumed that the coexistence of Et₂AlCl and a 1: 1 complex formed from Et₂AlCl and HPT is important for activating the catalyst. Some examples are given which demonstrate higher activity of Et₂AlCl·HPT-TiCl₃ catalyst by the coexistence of Lewis acids such as Et₂AlCl, EtAlCl₂, AlCl₃, and Al₂O₃ than that of Et₂AlCl-TiCl₃ catalyst.

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Degradation of five kinds of castor oil polyurethanes by moisture and heat was studied. The castor oil polyurethanes were prepared by reacting refined castor oil with tolylene diisocyanate, 4, 4′-diphenylmethane diisocyanate, 1, 5-naphthyl diisocyanate, hexamethylene diisocyanate, and xylene diisocyanate. The cured polyurethanes were exposed to the atmosphere at 80°C and 95% relative humidity, and their effective crosslinking density, hardness and benzene-soluble fraction were measured as a function of exposure time. Effective crosslinking density was determined by stress-strain measurement. The polymer-solvent interaction parameter was calculated from the Flory-Rehner's equation using both the equilibrium swelling ratio in benzene and the effective crosslinking density. The obtained results are as follows. (1) The aromatic polyurethanes are more stable than the aliphatic ones. (2) Curing agents, triethylenediamine and dibutyltin dilaurate, accelerate the moistheat degradation of castor oil polyurethane. (3) The moist-heat degradation of polyurethane is an autocatalytic process. (4) The polymer-solvent interaction parameter increases as the moist-heat degradation proceeds.

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In order to elucidate formation of a radial refractive-index distribution in a light-focusing plastic rod (LFR) prepared by photocopolymerization, methyl methacrylate (M₁) and vinyl benzoate (M₂) were copolymerized in a cuvette under irradiation of UV at 25°C. The reactivity ratios were determined to be r₁=8.52 and r₂=0.070. The following results were obtained. (1) Copolymers containing 30-40 wt-% monomers were deposited on the inner wall of the cuvette when monomer conversion reached a critical value of 25-27%. (2) Thickness of the copolymer layer increased with the irradiation time, while polymer content in the copolymer layer leveled off. (3) Polymer content in the liquid part (monomer layer) increased gradually with the irradiation time. An expression for radial refractive-index distribution in the LFR was derived on the basis of the above results. Profiles of index-distribution and index-difference between center axis and periphery were calculated by a computer according to the above expression, being in agreement with those of the representative LFR respectively, except that the calculated index-gradient near the center axis was steeper than the observed one.

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The ring opening polymerization of 3-hydroxy-1-propane sulfonic acid sultone (PS) was carried out at 80°C in bulk using tertiary amines, sulfobetaines and quaternary ammonium tosylates as initiators. It was considered that the polymerizations of PS with the tertiary amines and sulfobetaines proceeded by a macrozwitterion mechanisum, while the polymerization with the quaternary ammonium tosylates proceeded by the reaction of the ion pair with the monomer:
-CH₂SO₂O^{- +}NR₃/CH₃+CH₂+CH₂CH₂/SO₂-O→-CH₂SO₂OCH₂CH₂CH₂SO₂O^{- +}NR₃/CH₃
The structures of end groups in the polymers were comfirmed from their NMR spectra. The rate constant, k_p, for the polymerization by a macrozwitterion mechanisum coincided with that by the ion pair mechanism within an experimental error. From this result, it was concluded that the propagating species in the polymerization is presumably free ion, sulfonate anion, which is solvated with monomer.

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Formation of block copolymer by ultrasonic irradiation in benzene solution containing polystyrene (PSt) and either poly (vinyl acetate) (PVAc) or poly (ethylene oxide) (PEO) of different molecular weight was studied at various polymer concentrations and irradiation times. Weight fractions (%) of the (St-VAc) block copolymers (I) and the (St-EO) block copolymers (II) produced by this method under the experimental conditions (PSt-PVAc, 8.3-33.3g/l, 7-20 min; PSt-PEO, 8.0-20.0g/l, 5-20 min) were 3.9-7.6 and 4.4-20.0, respectively. These values decreased with the increase of polymer concentration, but did not always increase with increasing irradiation time. Molecular weight distributions of I and II were as broad as those of homopolystyrene irradiated by ultrasonic waves and the average compositions of I and II were rich in styrene units. From the results, effect of different combination of polymers on the weight fraction and on the composititions of the block copolymers was discussed.

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Effects of the polymerization degree and polymerization procedures of poly (vinyl chloride) (PVC), and of the amounts and kinds of plasticizers on the crosslinking of PVC 6-dibutylamino-1, 3, 5-triazine-2, 4-dithiol and MgO have been studied with respects to the crosslinking rate, induction period and the efficiency of crosslinking agent. The rate constant hardly changed by the polymerization degree, but was dependent on the polymerization procedures. PVC prepared by an emulsion polymerization using a nonion surface activator was crosslinked at a higher rate than PVC's prepared by a suspension and a bulk polymerizations. The rate constant was not dependent on plasticizer content, but increased with an increase in the polarity of plasticizers. Induction period decreased, whereas efficiency of the crosslinking agent increased, with an increase in polymerization degree of and a decrease in plasticizer content. It was concluded that the drop in the efficiency is due to the intramolecular crosslinking.

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To obtain polymers having high dielectric constant and low dielectric loss, new polymers which contain cyanine cations in the side chain are synthesized by neutralizing a styrene-methacrylic acid copolymer (MA, 21 mol%) with KOH and exchanging the cation with dye molecules. Dielectric constant of the polymers increases with increasing amount of the cyanine cation and that of the polymer containing maximum amount of the cyanine cation (42 wt%) is 1.6 times as high as the original value for the polymer free from the cyanine cation.

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A variety of quaternary ammonium salts of cross-linked poly (4-vinylpyridine) resins were prepared from 4-vinylpyridine-divinylbenzene copolymer and alkyl bromides of various chain length (C₂-C₁₆). Using these resins as catalyst, the triphase displacement of 1-bromooctane by cyanide ion was investigated. The yield of 1-cyanooctane was 86% in a reaction at 110°C for 4 hr with stirring and using the lauryl bromide catalyst. Catalysts derived from alkyl bromides with longer chains showed higher activities in the reaction. Optimum weight ratio of the catalyst and molar ratio of sodium cyanide to 1-bromooctane were 0.39 and 12, respectively. Kind of added organic solvents changed the catalytic effectiveness of the resins in the following order: benzene>toluene>o-dichlorobenzene. The rate of reaction using 1-halooctanes as a catalyst component increased in the order of 1-iodooctane>1-bromooctane>1-chlorooctane.

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