Method for producing high molecular weight EPDM elastomer using metallocene / alumoxane catalyst system

摘要

A process for producing a high molecular weight EPDM elastomer having low crystallinity using a bridged bis-metallocene-alumoxane catalyst wherein the metallocene component of the catalyst has the formula: CHEM wherein "M" is titanium, zirconium or hafnium; each "R1" independently is a C1 to C20 linear, branched or cyclic alkyl group or a C2 to C4 alkylene which forms a fused ring system; "R2" is a C1 to C6 linear, branched or cyclic alkylene group, an alkyl substituted silanylene group or an alkyl substituted silaalkylene group; each "X" independently is a halogen, hydride, alkyl, aryl or chelating group, and "y" is an integer of 2 to 4.