Radiation-induced polymerization and copolymerization of diallylsilanes

Polymerization and copolymerization of dimethyldiallylsilane or diphenyldiallylsilane have been carried out by γ-ray irradiation. The measurement of NMR spectra of the polymers and copolymers revealed that cyclic and linear structural units were formed concurrently, and the molar ratio of the linear structural unit to the cyclic one in the polymer and the copolymer varied depending on the polymerization conditions. On the polymerization of diallylsilane in bulk and in an acetone solution, the molar ratio of a linear structural unit in the polymer decreased with the decreasing monomer concentration. On the copolymerization of diallylsilane with N-ethylmaleimide, an electron-accepting comonomer, the linear structural units of diallylsilane in the copolymer increased with the increasing mole % of N-ethylmaleimide in the monomer mixture. Equations concerning the molar ratio of the linear structural unit to the cyclic one in the polymer and the copolymer have been derived, and the coincidence of the theoretical values with the experimental data for the copolymerization was observed. (author)