Catalyst composition comprising shuttling agent for tactic/ atactic multi-block copolymer formation
View Patent ↗Copolymers, especially multi-block copolymer containing therein two or more segments or blocks differing in tacticity, are prepared by polymerizing propylene, 4-methyl-1-pentene, or another C 4-8 α-olefin in the presence of a composition comprising the admixture or reaction product resulting from combining: (A) a first metal complex olefin polymerization catalyst, (B) a second metal complex olefin polymerization catalyst capable of preparing polymers differing in tacticity from the polymer prepared by catalyst (A) under equivalent polymerization conditions, and (C) a chain shuttling agent.
1. A multi-block copolymer formed by polymerizing propylene, 4-methyl-1-pentene, or another C 4-8 α-olefin in the presence of a composition comprising the admixture or reaction product resulting from combining:
(A) a first olefin polymerization catalyst,
(B) a second olefin polymerization catalyst capable of preparing a polymer differing in tacticity from the polymer prepared by catalyst (A) under equivalent polymerization conditions, and
(C) a chain shuttling agent
wherein the molecular weight distribution, Mw/Mn, of the copolymer is 1.7 to 2.9 and the shuttling agent is a dihydrocarbyl zinc-compound containing from 1 to 12 carbons in each hydrocarbyl group.
2. A multi-block copolymer formed by polymerizing propylene, 4-methyl-1-pentene, or another C 4-8 α-olefin, and a copolymerizable comonomer in the presence of a composition comprising the admixture or reaction product resulting from combining:
(A) a first olefin polymerization catalyst that under the conditions of polymerization forms a tactic polymer of one or more C 3-30 α-olefins,
(B) a second olefin polymerization catalyst that under the conditions of polymerization forms a polymer having a tacticity less than 95 percent of the polymer formed by catalyst (A), and
(C) a chain shuttling agent
wherein the molecular weight distribution, Mw/Mn, of the copolymer is 1.7 to 2.9, the copolymer has a PDI fitting a Schulz-Flory distribution, and the shuttling agent is a dihydrocarbyl zinc- compound containing from 1 to 12 carbons in each hydrocarbyl group.
3. The multi-block copolymer of claim 2 , consisting essentially of propylene in polymerized form, said copolymer containing therein two or more segments or blocks differing in tacticity.
4. The multi-block copolymer of claim 2 , consisting essentially of 4-methyl-1-pentene in polymerized form, said copolymer containing therein two or more segments or blocks differing in tacticity.
5. The multi-block copolymer according to claim 2 containing therein four or more segments or blocks differing in tacticity.
6. A functionalized derivative of the multi-block copolymer of claim 1 .
7. A functionalized derivative of the multi-block copolymer of claim 5 .
8. A homogeneous polymer mixture comprising:
(1) an organic or inorganic polymer and (2) the multi-block copolymer of claim 2 .
9. A composition comprising the multi-block copolymer of claim 2 in the form of a film, at least one layer of a multilayer film, at least one layer of a laminated article, a foamed article, a fiber, a nonwoven fabric, an injection molded article, a blow molded article, or a roto-molded article.
10. A composition comprising the functionalized derivative of the multi-block copolymer of claim 5 in the form of a film, at least one layer of a multilayer film, at least one layer of a laminated article, a foamed article, a fiber, a nonwoven fabric, an injection molded article, a blow molded article, or a roto-molded article.
11. A composition comprising the homogeneous polymer mixture of claim 8 in the form of a film, at least one layer of a multilayer film, at least one layer of a laminated article, a foamed article, a fiber, a nonwoven fabric, an injection molded article, a blow molded article, or a roto-molded article.
12. A copolymer according to claim 2 , wherein the shuttling agent is diethylzinc.