A polymerization to form a branched polyolefin, in which polymerization an ethylene copolymerization catalyst and an ethylene oligomerization catalyst form a series of ethylene oligomers that are α-olefins are both present, gives an improved polyethylene if the oligomerization catalyst has a to relatively high Schulz-Flory constant.
Higher molecular weight linear α-olefins are produced by the oligomerization of ethylene using certain iron complexes of 2,6-diacylpyridinedimimines or 2,6-pyridinedicarboxaldehydedimines as catalysts. These iron complexes are more sterically hindered than those heretofore used. The resulting α-olefins are useful as comonomers in olefin polymerizations.
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.
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.
A polymerization to form a branched polyolefin, in which polymerization an ethylene copolymerization catalyst and an ethylene oligomerization catalyst form a series of ethylene oligomers that are α-olefins are both present, gives an improved polyethylene if the oligomerization catalyst has a relatively high Schulz-Flory constant.