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Highly Active and Isospecific Styrene Polymerization Catalyzed by Zirconium Complexes Bearing Aryl-substituted [OSSO]-Type Bis(phenolate) Ligands.

ABSTRACT: [OSSO]-type dibenzyl zirconium(IV) complexes 9 and 10 possessing aryl substituents ortho to the phenoxide moieties (ortho substituents, phenyl and 2,6-dimethylphenyl (Dmp)) were synthesized and characterized. Upon activation with dMAO (dried methylaluminoxane), complex 9 was found to promote highly isospecific styrene polymerizations ([mm] = 97.5%?99%) with high molecular weights M_w up to 181,000 g·mmol^-1. When the Dmp-substituted pre-catalyst 10/dMAO system was used, the highest activity, over 7700 g·mmol(10)^-1·h^-1, was recorded involving the formation of precisely isospecific polystyrenes of [mm] more than 99%.

SUBMITTER: Nakata N

PROVIDER: S-EPMC6432521 | biostudies-literature | 2016 Jan

REPOSITORIES: biostudies-literature

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Highly Active and Isospecific Styrene Polymerization Catalyzed by Zirconium Complexes Bearing Aryl-substituted [OSSO]-Type Bis(phenolate) Ligands.

Nakata Norio N Toda Tomoyuki T Saito Yusuke Y Watanabe Takanori T Ishii Akihiko A

Polymers 20160126 2

[OSSO]-type dibenzyl zirconium(IV) complexes 9 and 10 possessing aryl substituents ortho to the phenoxide moieties (ortho substituents, phenyl and 2,6-dimethylphenyl (Dmp)) were synthesized and characterized. Upon activation with dMAO (dried methylaluminoxane), complex 9 was found to promote highly isospecific styrene polymerizations ([mm] = 97.5%⁻99%) with high molecular weights Mw up to 181,000 g·mmol-1. When the Dmp-substituted pre-cata ...[more]

PMID: 30979125

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