Copolymer compositions containing a narrow MWD component and process of making same
AssigneeExxon Research & Engineering Co.
InventorsCharles Cozewith, Shiaw Ju, Gary W. Verstrate
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Abstract
The present invention relates to polymeric composition of a first copolymer which includes at least one copolymer having at least one of Mw/Mn less than 2 and Mz/Mw less than 1.8; and a second copolymer having Mw/Mn greater than or equal to 2. The composition can be produced by preparing the first and second copolymers in different reactors and blending them. The blend can also be produced in a single reactor by initiating the reaction to prepare one copolymer, and adding additional reactants, or recycling the reaction mixture, during the reaction to produce the other copolymer.
Claims9
An ethylene alpha-olefin copolymer composition comprising:
- (a) a first copolymer having at least one of Mw/Mn less than 2 and M.sub.z /M.sub.w less than 1.8;
- and
- (b) a second copolymer having M.sub.w /M.sub.n greater than or equal to 2, wherein said first copolymer is an ethylene alpha-olefin copolymer formed of monomers comprising 3-18 carbon atoms, wherein 95 weight percent of the copolymer chains of the first copolymer have an ethylene composition that differs from the average weight percent ethylene composition of the first copolymer by not more than 15 weight percent, and wherein at least 2 portions of essentially each copolymer chain of the first copolymer, each portion comprising at least about 5 weight percent of the chain, differ in composition from one another by at least about 5 weight percent ethylene.
Dependencies are inferred from the claim text.