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Title: Catalyst-controlled stereoselective cationic polymerization of vinyl ethers
The tacticity of vinyl polymers has a profound effect on their physical properties. Despite the well-developed stereoselective methods for the polymerization of propylene and other nonpolar α-olefins, stereoselective polymerization of polar vinyl monomers has proven more challenging. We have designed chiral counterions that systematically bias the reactivity and chain-end stereochemical environment during cationic polymerization. This approach overrides conventional chain-end stereochemical bias to achieve catalyst-controlled stereoselective polymerization. We demonstrate that this method is general to vinyl ether substrates, providing access to a range of isotactic poly(vinyl ether)s with high degrees of isotacticity. The obtained materials display the tensile properties of commercial polyolefins but adhere more strongly to polar substrates by an order of magnitude, indicating their promise for next-generation engineering applications.
Authors:
;
Award ID(s):
1726291
Publication Date:
NSF-PAR ID:
10104954
Journal Name:
Science
Volume:
363
Issue:
6434
Page Range or eLocation-ID:
1439 to 1443
ISSN:
0036-8075
Sponsoring Org:
National Science Foundation
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