| abstract |
A process for producing a 1-butene polymer comprising the step of polymerizing 1-butene in the presence of a catalyst system obtainable by contacting: n nb) at least a metallocene compound of formula (Ia) in the meso or meso-like form: n n nwherein M is an atom of a transition metal p is an integer from 0 to 3, X, same or different, is a hydrogen atom, a halogen atom, or a hydrocarbon group. L is a divalent C 1 -C 40 hydrocarbon radical R 1 and R 2 , equal to or different from each other, are C 1 -C 40 hydrocarbon radicals; T, equal to or different from each other, is a moiety of formula (IIa), (IIb) or (IIc): n n nwherein R 3 and R 5 are a C 1 -C 40 hydrocarbon radical; R 4 and R 6 , equal to or different from each other, are hydrogen atoms or C 1 -C 40 hydrocarbon radicals and R 7 and R 8 , equal to or different from each other, are hydrogen atoms or C 1 -C 40 hydrocarbon radicals n nb) at least a metallocene compound of formula (Ib) in the racemic (rac) or racemic-like form n nc) an alumoxane or a compound capable of forming an alkyl metallocene cation. |