| abstract |
Random or block copolymers with (1-hydro-1-R-1-sila-cis-pent-3-ene), poly(1-hydro-1-R-3,4 benzo-1-sila pent-3-ene), and disubstituted 1-silapent-3-ene repeating units of the general formula ##STR1## where R is hydrogen, an alkyl radical containing from one to four carbon atoms or phenyl, R 1 is hydrogen, an alkyl radical containing from one to four carbon atoms, phenyl or a halogen and R 2 is hydrogen, or R 1 and R 2 are combined to form a phenyl ring, are prepared by the anionic ring opening polymerization of silacyclopent-3-enes or 2-silaindans with an organometallic base and cation coordinating ligand catalyst system or a metathesis ring opening catalyst system. |