A PROCESS FOR PREPARING AN IN SITU POLYETHYLENE BLEND.

摘要

A process for the production of an in situ polyethylene blend comprising contacting at least one metallocene based catalyst system with one or more alpha-olefines in each of two or more reactors connected in series, in the gas phase, under polymerization conditions, with the provisos that: (a) ethylene is introduced into each reactor; (b) optionally, an alpha-olefin having at least 3 carbon atoms or a diene is introduced into at least one reactor; (c) the mixture of ethyelene polymer matrix and catalysts formed in the first reactor in the series is transferred to the subsequent reactors in the series; and (d) the polymerization conditions in each reactor are such that a high molecular weight polymer is formed in at least one reactor and a low molecular weight polymer formed in at least one other reactor.