abstract |
Catalyst system, the catalyst system comprising (i) at least one metallocene complex of formula (I), (I) wherein Mt1 is Hf, X is a sigma-donor ligand, R 1 , R 2 , R 3 are the same or different from each other and can be hydrogen or a saturated linear or branched C 1 -C 10 alkyl, whereby the alkyl group can optionally contain up to 2 heteroatoms belonging to groups 14-16 of the periodic table, or R 1 and R 2 or R 2 and R 3 can form a ring having 4 to 6 C-atoms and 1 to 3 double bonds, R 4 and R 5 are the same or different from each other and can be saturated linear or branched C 1 -C 10 alkyl, C 5 -C 10 aryl, C 6 -C 20 alkylaryl or C 6 -C 20 arylalkyl groups, which can optionally contain up to 2 heteroatoms belonging to groups 14-16 of the periodic table, n can be 1 to 5, Ar is a C 6 -C 20 -aryl or -heteroarylgroup, which can be unsubstituted or substituted by 1 to 5 linear or branched C 1 - C 10 alkyl group(s), and (ii) a boron containing cocatalyst. |