摘要 |
Propylene isoblock polymers with 0.5 to 10 mol %, based on the total polymer, of randomly distributed ethylene content and with a narrow molecular weight distribution and rubber-like properties are obtained when propylene is polymerized using a catalyst comprising an aluminoxane and a chiral metallocene, containing bridges, of formula I: in which M1 is preferably hafnium or zirconium, R1 and R2 are preferably halogen (e.g. C1) atoms, R3 through R6 are hydrogen or C1-C10-alkyl, and pair of adjacent radicals R3, R4, R5, and R6 can form an aromatic ring with the C-atoms to which they are bonded, and R7 is preferably -Si(CH3)2-Si(CH3)2-.
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