| abstract |
Metallocenes of formula (XI) are new, wherein M<1> = Ti, Zr, Hf, V, Nb or Ta; R<14>, R<15> = H, halogen, 1-10 C alkyl, 1-10 C alkoxy, 6-10 C aryl, 6-10 C aryloxy, 2-10 C alkenyl, 7-40 C arylalkyl, 7-40 C alkylaryl or 8-40 C arylalkenyl; R<16>, R<17> = 9-fluorenyl and 1-(3-isopropyl)cyclopentadienyl, or 9-fluorenyl and 1-(3-t-butyl)cyclopentadienyl, forming a sandwich structure with M<1>; R<18> = a one or more membered bridge, which connects R<16> and R<17>, pref. -(R<19>)M<2)<R<20>)-, -(R<19>)M<2)<R<20>)-(R<19>)M<2)<R<20>)-, -(R<19>)M<2)<R<20>)-CR2<21>-, -(R<19>)C(R<20>)-, -O-(R<19>)M<2)<R<20>)-, -(R<19>)C(R<20>)-(R<19>)C(R<20>)-, =BR<19>, =AlR<19>, -Ge-, -Sn-, -O-, -S-, =SO, =SO2, =NR<19>, =CO, =pr<19> or =P(O)R<19>; R<19>, R<20>, R<21> = independently H, halogen, 1-10 C alkyl, 1-10 C fluoroalkyl, 6-10 C aryl, 1-10 C alkoxy, 2-10 C alkenyl, 7-40 C arylalkyl, 8-40 C arylalkenyl or 7-40 C alkylaryl, or R<19> and R<20> or R<19> and R<21> form together a ring with bonded atoms; and isopropylene or diphenylmethylene; and M<2> = Si, Ge or Sn. Catalysts comprising a linear type aluminoxane of formula (IX) and/or a cyclic type aluminoxane of formula (X), in addn. to (XI) are also claimed; R<13> = 1-5 C alkyl, phenyl or benzyl; and n = 0-50. |