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 or Hf, R<1> and R<2> are alkyl or halogen, R<3> is hydrogen, R<4> to R<6> are alkyl or aryl, -(CR<8>R<9>)m-R<7>-(CR <8>R<9>)n-, a single- or multimembered chain in which R<7> may also be a (substituted) heteroatom, and m + n is zero or 1. |