Living coordinative chain transfer polymerization with dynamic counterion exchange
AssigneeUniversity of Maryland, College Park
InventorsLawrence R. Sita, Jia Wei, Wei Zhang
Life of this patent
Estimating the term…
Abstract
Disclosed is a method of producing a polyolefin composition comprising contacting a metal alkyl and a first olefin monomer, then adding a first co-catalyst, a second co-catalyst, a pre-catalyst, and a second olefin monomer. The method allows for the production of a series of copolymers with tunable incorporation ratios of the first olefin monomer. The method also allows for the production of polyolefins of low molecular weights and narrow molecular weight distributions.
Claims19
A method of producing a polyolefin composition comprising:
- (a) contacting a metal alkyl and a first olefin monomer;
- (b) adding a pre-catalyst, a first co-catalyst, a second co-catalyst, and a second olefin monomer, wherein the first co-catalyst forms a stronger ion-pair with the pre-catalyst than the second co-catalyst;
- and
- (c) polymerizing by ternary living coordinative chain transfer said first and second monomers for a time sufficient to form said polyolefin.
A method of controlling the level of incorporation of a first olefin monomer into a polyolefin composition comprising:
- (a) contacting a first olefin monomer and a metal alkyl;
- (b) adding a pre-catalyst, a first co-catalyst, a second co-catalyst, and a second olefin monomer, wherein the first co-catalyst forms a stronger ion-pair with the pre-catalyst than the second co-catalyst;
- and
- (c) polymerizing by ternary living coordinative chain transfer said first and second monomers for a time sufficient to form said polyolefin;
- wherein increasing the amount of the second co-catalyst decreases the level of incorporation of the first olefin monomer.
Dependencies are inferred from the claim text.