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Ortho-Functionalized Dibenzhydryl Substituents in ?-Diimine Pd Catalyzed Ethylene Polymerization and Copolymerization.

ABSTRACT: Sterically bulky diarylmethyl-based ligands have received increasing attention in the field of late-transition-metal catalyzed olefin polymerization. Ortho-substituents may have a significant impact on the performance of diarylmethyl-based ?-diimine Pd catalysts. In this contribution, a series of ?-diimine Pd catalysts bearing ortho-methoxyl/hydroxyl functionalized dibenzhydryl units were prepared, characterized, and investigated in ethylene polymerization and copolymerization with methyl acrylate (MA). The catalytic performances were improved by introducing more ortho-substituents. The catalysts exhibited good thermal stabilities at high temperatures, producing branched polyethylenes. The catalysts bearing hydroxyl groups possessing intramolecular H-bonding, resulted in slightly higher incorporation ratios of MA unit when compared with the catalysts bearing methoxyl groups.

SUBMITTER: Muhammad Q

PROVIDER: S-EPMC7692462 | biostudies-literature | 2020 Oct

REPOSITORIES: biostudies-literature

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Ortho-Functionalized Dibenzhydryl Substituents in α-Diimine Pd Catalyzed Ethylene Polymerization and Copolymerization.

Muhammad Qasim Q Pang Wenmin W Wang Fuzhou F Tan Chen C

Polymers 20201028 11

Sterically bulky diarylmethyl-based ligands have received increasing attention in the field of late-transition-metal catalyzed olefin polymerization. Ortho-substituents may have a significant impact on the performance of diarylmethyl-based α-diimine Pd catalysts. In this contribution, a series of α-diimine Pd catalysts bearing ortho-methoxyl/hydroxyl functionalized dibenzhydryl units were prepared, characterized, and investigated in ethylene polymerization and copolym ...[more]

PMID: 33126562

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