Homopolymerization and copolymerization of phenyltrichlorosilane by sonochemical reductive coupling in the presence of sodium

Soluble polymers have been prepared by the sonochemical reductive coupling of phenyltrichlorosilane in toluene in the presence of sodium. Copolymers of phenyltrichlorosilane with phenylmethyldi-chlorosilane were synthesized. The obtained products are of relatively low molecular weight (ˉM_n<10,000). Investigations by ²⁹ Si NMR, UV and by the kinetic studies of the iodine addition indicate that polymers consist of fused cyclopolysilanes with 40% content of strained rings (probably four-membered). Homopolymerization and copolymerization of n-hexyl-trichlorosilane and methyltrichlorosilane is compared with that of phenyltrichlorosilane. The former monomer yields soluble homopolymer and copolymers of relatively higher molecular weights than phenyltrichlorosilane. Methyltrichlorosilane yields usually insoluble products and only at a concentration below 20%, were soluble copolymers formed.