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.sup.1 is hydrogen, an alkyl radical containing from one to four carbon atoms, phenyl or a halogen and R.sup.2 is hydrogen, or R.sup.1 and R.sup.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.
具有(1-羟基-1-R-1-
硅-顺-戊-3-烯)、聚(1-羟基-1-R-3,4-苯并-1-
硅-戊-3-烯)和二取代的1-
硅-戊-3-烯重复单元的随机或嵌段共聚物,其一般式为##STR1##其中R是氢,含有1至4个碳原子的烷基基团或苯基,R.sup.1是氢,含有1至4个碳原子的烷基基团,苯基或卤素,R.sup.2是氢,或R.sup.1和R.sup.2结合形成苯环,通过有机
金属碱和阳离子配位
配体催化剂系统或交换开环催化剂系统的
硅环戊-3-烯或2-
硅吲哚的负离子开环聚合制备。