| 摘要 |
A highly effective catalyst system for the polymerisation of olefins comprises a cocatalyst, preferably an aluminoxane, and a metallocene of the formula (I) …<IMAGE>… in which, preferably, M<1> is Zr, R<1> and R<2> are an alkyl or halogen, R<3> to R<6> are alkyl, -(CR<8>R<9>)m-R<7>-(CR<8>R<9>)n- is a single- or multi-membered chain in which R<7> may also be a (substituted) heteroatom, and m + n is zero or 1. The catalyst system gives polymers of variable molecular weight and stereotacticity, depending on the selected substituents R<3> to R<6>, at industrially relevant polymerisation temperatures. |
