Process for preparing alpha-olefin copolymers having a narrow MWD and broad compositional distribution
Patent 5191042 Issued on March 2, 1993. Estimated Expiration Date: 
September 25, 2011. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
September 25, 2011. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent References 3000866 3301834 3349064 3489729 Narrow MWD alpha-olefin copolymers Patent #: 4540753 InventorAssigneeApplicationNo. 767523 filed on 09/25/1991US Classes:526/144, Non-metal material is organic halogen-containing compound526/169.2, Transition metal is vanadium526/281, Bridged monomer526/282, Contains an exterior ethylenic substituent bonded to a single carbon atom of the bridged ring system526/336Ethylenic groups are non-conjugated, e.g., divinylbenzene, etc.ExaminersPrimary: Teskin, FredAttorney, Agent or FirmForeign Patent References
International ClassesC08F 002/04C08F 236/20 AbstractThe present invention is directed toward novel copolymers of ethylene and at least one other alpha-olefin monomer which copolymers have an intermolecular compositional distribution (CD), such that at least about 25% by weight of the polymer differs from the mean ethylene content of the polymer by at least plus or minus 5 wt % ethylene and a relatively narrow molecular weight distribution (MWD) such that the weight average molecular weight (Mw) of the polymer divided by the number average molecular weight (Mn) by the polymer is not greater than about 5.0.The polymers of this invention, which are characterized by exceptional green strength and good processing properties, may be prepared using a catalyst system comprising:a) a vanadium compound with a valence of 3 or more;b) a triorgano aluminum compound; andc) a specific halogenated organic promoter used in catalytic amounts.The catalyst system allows for efficient polymerization of high quality polymer products and at generally higher polymerization temperatures of up to about 140° C. to yield higher molecular weight polymer products which are essentially free of gel, and which possess excellent green strength and processability.Other References
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