| abstract |
A process for copolymerizing ethylene, one or more non-conjugated cyclic diene and optionally one or more alpha olefins of formula CH 2 =CHT wherein T is a C 1 -C 20 alkyl radical comprising the step of contacting the monomers under polymerization conditions in the presence of a catalyst system comprising a metallocene compound of formula (I) wherein: M is titanium zirconium or hafnium; X, is a hydrogen atom, a halogen atom, a R, OR, OR'O, OSO 2 CF 3 , OCOR, SR, NR 2 or PR 2 group wherein R is an hydrocarbon radical and R' is a C 1 -C 20 -alkylidene, C 6 -C 20 -arylidene, C 7 -C 20 -alkylarylidene, or C 7 -C 20 -arylalkylidene radical; R 1 , is a C 1 -C 20 -alkyl radical; R 2 , R 3 , R 4 , R 5 , R 6 and R 7 are hydrogen atoms, or C 1 -C 20 hydrocarbon radicals or two or more R 2 , R 3 , R 4 , and R 5 can also be joined to form a C 3 -C 10 ring; L is a divalent C 1 -C 40 hydrocarbon radical. |