Olefin polymerization process

摘要

An ethylene oligomerization catalyst that oligmerizes ethylene to a series of α-olefins and that has a Schulz-Flory constant of about 0.75 to 0.995 produces a stream of α-olefins. This stream is then added to a vessel containing ethylene and a copolymerization catalyst that copolymerizes ethylene and α-olefins. The resulting branched polyethylene often has good processing properties. The good processing is presumably due to the presence of “long chain branching”. Such polymers are useful for films and other packaging materials, and for molding resins for molding parts such as industrial, automotive or electrical parts.

主权项

1. A process for the manufacture of a branched polyethylene, comprising,
(1) contacting ethylene with an ethylene oligomerization catalyst which produces a series of α-olefins; and then (2) after said series of α-olefins is formed contacting in a liquid medium said series of α-olefins with a copolymerization catalyst and ethylene to form a branched polyethylene;and wherein said oligomerization catalyst which produces said series of α-olefins has a Schulz-Flory constant of about 0.80 to 0.995 under oligomerization process conditions, and wherein the branched polyethylene produced has a density of 0.930 or more.