Long chain branching in polyolefins from Ziegler-Natta catalysts
AssigneeExxon Research & Engineering Co.
InventorDennis B. Malpass
Life of this patent
Estimating the term…
Abstract
Generally, linear polyethylene containing long chain branching is obtained by polymerizing ethylene in the presence of a catalyst comprising a transition metal compound such as titanium chloride, an organoaluminum compound represented by the formula R.sub.1 R.sub.2 AlR.sub.p wherein R.sub.1 and R.sub.2 are the same or different hydrocarbyl groups having from 1 to 18 carbon atoms and R.sub.p is a polymeric hydrocarbyl group containing long chain branching aluminum alkyl cocatalyst.
Claims2
A process for producing linear polyethylene containing a terminal fragment having long chain branches, said process comprising polymerizing ethylene in the presence of a catalyst comprising:
- (a) a Group 4B to 8 transition metal compound,
- (b) an organoaluminum compound of the general formula R.sub.1 R.sub.2 AlR.sub.p wherein R.sub.1 and R.sub.2 are the same or different hydrocarbyl groups having from 1 to 18 carbon atoms and R.sub.p is a polymeric hydrocarbyl group having a number average molecular weight in the range of about 1000 to about 100,000 and a long chain branching frequency of about 0.005 to about 0.0005 per unit molecular weight, and
- (c) an aluminum alkyl cocatalyst.
Dependencies are inferred from the claim text.