Self limiting catalyst composition and propylene polymerization process
AssigneeDow Global Technologies LLC
InventorsLinfeng Chen, Richard E. Campbell, Jr.
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Abstract
A catalyst composition for the polymerization of propylene comprising one or more Ziegler-Natta procatalyst compositions comprising one or more transition metal compounds and one or more esters of aromatic dicarboxylic acid internal electron donors; one or more aluminum containing cocatalysts; a selectivity control agent (SCA) comprising at least one silicon containing compound containing at least one C1-10 alkoxy group bonded to a silicon atom, and one or more activity limiting agent (ALA) compounds comprising one or more aliphatic or cycloaliphatic carboxylic acids; alkyl-, cycloalkyl- or alkyl(poly)(oxyalkyl)-(poly)ester derivatives thereof; or inertly substituted derivatives of the foregoing.
Claims19
A polymerization process comprising:
- charging an effluent of a first polymerization reactor to a second polymerization reactor;
- contacting the effluent with propylene and a copolymerizable comonomer under polymerization conditions in the second polymerization reactor;
- adding a mixture of a selectivity control agent (SCA) comprising one or more silicon containing compounds and an activity limiting agent (ALA) selected from the group consisting of a C1-20 alkyl ester of an aliphatic C8-20 monocarboxylic acid, a C2-20 alkyl mono- or poly-carboxylate derivative of a C2-100 polyglycol, and combinations thereof to the second polymerization reactor;
- and
- forming a copolymer.
A polymerization process comprising:
- preparing a polypropylene in a first polymerization reactor;
- preparing a copolymer of ethylene and propylene in the presence of the polypropylene in a second polymerization reactor;
- and
- adding, to at least one of the polymerization reactors, a mixture of a selectivity control agent (SCA) comprising one or more silicon containing compounds and an activity limiting agent (ALA) selected from the group consisting of a C1-20 alkyl ester of an aliphatic C8-20 monocarboxylic acid, a C2-20 alkyl mono- or poly-carboxylate derivative of a C2-100 polyglycol, and combinations thereof.
A polymerization process comprising:
- preparing a copolymer of ethylene and propylene in the presence of a polypropylene in a polymerization reactor under polymerization conditions;
- and
- adding, to the polymerization reactor, a mixture of a selectivity control agent (SCA) comprising one or more silicon containing compounds and an activity limiting agent (ALA) selected from the group consisting of a C1-20 alkyl ester of an aliphatic C8-20 monocarboxylic acid, a C2-20 alkyl mono- or poly-carboxylate derivative of a C2-100 polyglycol, and combinations thereof.
Dependencies are inferred from the claim text.