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Molecular weight control in organochromium olefin polymerization catalysis by hemilabile ligand-metal interactions.

ABSTRACT: A series of Cr(III) complexes based on quinoline-cyclopentadienyl ligands with additional hemilabile side arms were prepared and used as single-site catalyst precursors for ethylene polymerization. The additional donor functions interact with the metal centers only after activation with the co-catalyst. Evidence for this comes from DFT-calculations and from the differing behavior of the complexes in ethylene polymerization. All complexes investigated show very high catalytic activity and the additional side arm minimizes chain-transfer reactions, leading to increase of molecular weights of the resulting polymers.

SUBMITTER: Mark S

PROVIDER: S-EPMC4979879 | biostudies-literature | 2016

REPOSITORIES: biostudies-literature

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Molecular weight control in organochromium olefin polymerization catalysis by hemilabile ligand-metal interactions.

Mark Stefan S Wadepohl Hubert H Enders Markus M

Beilstein journal of organic chemistry 20160704

A series of Cr(III) complexes based on quinoline-cyclopentadienyl ligands with additional hemilabile side arms were prepared and used as single-site catalyst precursors for ethylene polymerization. The additional donor functions interact with the metal centers only after activation with the co-catalyst. Evidence for this comes from DFT-calculations and from the differing behavior of the complexes in ethylene polymerization. All complexes investigated show very high catalytic activity and the add ...[more]

PMID: 27559387

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