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Asahara and coworkers have reported that methyl methacrylate') and polymerize in the presence of an anionic surfactant without an initiator. They suggested that an interaction between the vinyl monomers and the micelle of the surfactant participates in the polymerization.We found that styrene polymerizes in an aqueous system on irradiation with a tungsten lamp in the presence of N-laurylpyridinium azide (1). A comparable polymerization is unknown and the reaction mechanism is still obscure. In this communication some observations will be described. Experiment a1 Part N-Laurylpyridinium azide (1):The preparation and analysis of 1 were performed according to the procedures reported previously4': 1 was prepared from N-laurylpyridinium chloride (LPC) and sodium azide by ion-exchange reaction (8 h) in purified tetrahydrofuran (THF) in the dark. The ion-exchange ratio was 98%. The chemical grade sodium azide was extracted with purified THF in a Soxhlet extractor before the ion-exchange reaction to remove THF soluble impurities, otherwise the obtained 1 became sometimes uneffective.Cetyltrimeth~~lammonium chloride (CTAC): Chemical grade product was recrystallized from THF. Cetyltrimethylammonium azide (CTAA): A similar ion-exchange procedure gave CTAA from CTAC;Vinyl monomers: All vinyl monomers were purified by usual methods.the ion-exchange ratio was 97 %. Photopolymerization

Benzidinetetrazonium chloride (BTC)–CuCl and BTC–FeCl2 complexes were thermally converted to benzene‐soluble poly‐4,4′‐biphenylene plus small amounts of insoluble material. The soluble fraction was more stable than the insoluble fraction when heated at 300–500°C, although the solubility decreased. BTC in water was converted to an insoluble material by addition of alkali or cuprous ammonia solution. The C/(H + Cl) ratio indicated the existence of three to five side groups for each twenty phenyl groups of the insoluble fraction, while that of the soluble fraction showed few such groups. The number increased to one or more side groups for each phenyl nucleus as both soluble and insoluble fractions were heated to 500°C. A thin film of soluble fraction deposited on a copper plate showed an electrical conductivity in the range 10−2–10−3 ohm−1 cm−1 at 25°C and an energy gap (ΔEg) of 0.2–0.3 eV. However, a compressed specimen of the same soluble fraction showed little conductivity. Solventsoluble samples of substituted poly‐4,4,‐biphenylene were prepared by the same procedure. These materials cracked on processing, and accurate conductivity measurements could not be made.

Hydrolyses of p-nitrophenyl acetate (PNPA) and 3-acetoxy-N,N,N-trimethylanilinium iodide (ANTI) catalyzed by poly[p-vinyl(thiopheno1)-co-acrylic acid] (PSH) were studied in the pH range of 8 -93. The reaction of PNPA followed pseudo-first-order kinetics and was found to be catalyzed by the thiophenolate ions on the polymer backbone. In the case of positively charged ANTI, the rate of catalysis showed substrate saturation phenomena and could be described by a Michaelis-Menten kinetics. This indicates that this reaction proceeds via a complex formed by electrostatic interaction between the substrate and the negatively charged polymer catalyst. When ionic strength was increased to 0,12 molA the reaction did not further follow the Michaelis-Menten kinetics, suggesting that the complexation constant or the reaction rate of the complex might vary with the amount of the substrate incorporated in the polymer domain. Positively charged N,N,N-trimethylanilinium iodide competively inhibited the PSHcatalyzed hydrolysis of ANTI.

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