To obtain a high-molecular-weight copolymer by copolymerizing propylene with a comonomer in the presence of a specified metallocene catalyst system.
A starting material comprising 99.95-30wt.%, based on the total polymer, propylene and 0.5-70wt.% at least one comonomer (e.g. ethylene) is used. The metallocene catalyst system comprises a catalyst component represented by formula I (wherein M1 is a group 4b, 5b or 6b metal; R1 and R2 are each H, a 1-10C alkyl, a 1-10C alkoxyl, a 6-10C aryl or the like; R3 is H, a 1-20C hydrocarbon group or the like; R4 to R12 are each the same as R3 provided that two or more adjoining groups of them may be combined to form an aromatic ring or an alicyclic ring together with the connecting atoms) and a cocatalyst comprising an aluminoxane represented by formula II or III (wherein R17 is a 1-6C alkyl or the like; and (p) is 2-50). The catalyst component is used in a concentration of 10-3 to 10-8mol per dm3 of the reactor capacity, and the cocatalyst is used in a concentration of 10-5 to 10-1 mol per dm3 of the reactor capacity. The polymerization is carried out at 50-200°C under a pressure of 0.5-100 bar.
FURANKU KIYUBAA
BERUNTO BATSUHAMAN
