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Unprecedented 3,4-Isoprene and cis-1,4-Butadiene Copolymers with Controlled Sequence Distribution by Single Yttrium Cationic Species

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Indexed by:期刊论文

Date of Publication:2014-12-23

Journal:MACROMOLECULES

Included Journals:SCIE、Scopus

Volume:47

Issue:24

Page Number:8524-8530

ISSN No.:0024-9297

Abstract:Precisely controlling the stereochemistry of a copolymerization by single catalyst, and achieving copolymers with predicted sequences, is a challenging project in organometallic and macromolecular sciences. This article reports that the copolymerization of isoprene and butadiene with the 3,4- and cis-1,4 different regioselectivities has been accessed through employing a pyridylmethylene functionalized fluorenyl ligated yttrium cationic species. The thus unprecedented regularity combination is attributed mainly to the backbiting interaction of the penultimate unit of the polymer chain to the active central metal ion according to the DFT calculation. Moreover, the compositions can be adjusted by regulating the monomer feed ratio according to the copolymerization kinetics study.

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