Patent ID: 6291601
Filing Date: 2001-09-18
Classification: C08F,Y10S

Abstract:
A process for producing high density polyethylene in the presence of a metallocene catalyst system in two liquid full loop reactors in series, wherein in a first reactor a first polyethylene product is polymerised substantially by homopolymerisation of ethylene and hydrogen, and in a second reactor serially connected to the first reactor downstream thereof a second polyethylene product is copolymerised from ethylene and an alpha-olefinic comonomer comprising from 3 to 8 carbon atoms, and a hydrogenation catalyst is introduced into the reactants downstream of the first reactor, the hydrogenation catalyst comprising a second metallocene catalyst of general formula:Cp.sub.2 MX.sub.nwhere Cp is a substituted or unsubstituted cyclopentene dienyl group; M is a transition metal from Group IVB of the Periodic Table or vanadium; X is a halogen or a hydrocarbyl group having from 1 to 10 carbon atoms; and n is the valency of the metal M minus 2.