Patent ID: 8445608
Filing Date: 2013-05-21
Classification: C08F

Abstract:
1. A method for preparing long-chain-branched isotactic polypropylene that comprises the steps of: a) feeding propylene into a reactor; b) providing an oligomerisation catalyst system capable of producing macromers of propylene having vinyl-terminated chains; c) providing a metallocene catalyst system to copolymerise the macromers of step b) with propylene wherein said metallocene catalyst system comprises a catalyst component of formula having C1-symmetry or C2-symmetry wherein R′ is a mono-aryl-substituted methylene bridge, and wherein R b ,R c and R d are each independently selected from H or alkyl having from 1 to 12 carbon atoms, or aryl groups having up to 12 carbon atoms, or silyl groups substituted or unsubstituted wherein M is a metal Group 4 of the Periodic Table and wherein Q is halogen or alkyl having from 1 to 12 carbon atoms and an activating agent having an alkylating and ionising action, wherein the oligomerisation and copolymerisation are carried out in one step by inserting both catalyst components and the activating agent simultaneously in the reactor; d) retrieving polypropylene product.