摘要 |
A multistage process for obtaining an heterophasic propylene polymer comprising the following steps: step a) contacting under polymerization conditions propylene and optionally ethylene or one or more alpha olefins in the presence of a catalysts system, supported on a porous organic polymer, comprising: ii) one or more metallocene compounds of formula (1) wherein: 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 bridging group; R1, is a linear or branched, saturated or unsaturated C1 -C20-alkyl radical; R2 is a branched C1 -C20-alkyl radical; T, equal to or different from each other is a moiety of formula : wherein: the atom marked with the symbol bonds the atom marked with the same symbol in the compound of formula (I); R5 -R13, equal to or different from each other, are hydrogen atoms or hydrocarbon groups; ii) an alumoxane or a compound capable of forming an alkyl metallocene cation; and optionally iii) an organo aluminum compound; step b) contacting, under polymerization conditions, in a gas phase, ethylene and one or more alpha olefins and optionally in the presence of an additional organo aluminum compound.
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