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Copolymerization of Ethylene and Vinyl Fluoride by Self-Assembled Multinuclear Palladium Catalysts.

ABSTRACT: The self-assembled multinuclear PdII complexes {(Li-OPOOMe2)PdMe(4-5-nonyl-pyridine)}4Li2Cl2 (C, Li-OPOOMe2 = PPh(2-SO3Li-4,5-(OMe)2-Ph)(2-SO3--4,5-(OMe)2-Me-Ph)), {(Zn-OP-P-SO)PdMe(L)}4 (D, L = pyridine or 4-tBu-pyridine, [OP-P-SO]3- = P(4-tBu-Ph)(2-PO32--5-Me-Ph)(2-SO3--5-Me-Ph)), and {(Zn-OP-P-SO)PdMe(pyridine)}3 (E) copolymerize ethylene and vinyl fluoride (VF) to linear copolymers. VF is incorporated at levels of 0.1-2.5 mol% primarily as in-chain -CH2CHFCH2- units. The molecular weight distributions of the copolymers produced by D and E are generally narrower than for catalyst C, which suggests that the Zn-phosphonate cores of D and E are more stable than the Li-sulfonate-chloride core of C under copolymerization conditions. The ethylene/VF copolymerization activities of C-E are over 100 times lower and the copolymer molecular weights (MWs) are reduced compared to the results for ethylene homopolymerization by these catalysts.

SUBMITTER: Liu Q

PROVIDER: S-EPMC7407146 | biostudies-literature | 2020 Jul

REPOSITORIES: biostudies-literature

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Copolymerization of Ethylene and Vinyl Fluoride by Self-Assembled Multinuclear Palladium Catalysts.

Liu Qian Q Jordan Richard F RF

Polymers 20200719 7

The self-assembled multinuclear PdII complexes {(Li-OPOOMe2)PdMe(4-5-nonyl-pyridine)}4Li2Cl2 (C, Li-OPOOMe2 = PPh(2-SO3Li-4,5-(OMe)2-Ph)(2-SO3--4,5-(OMe)2-Me-Ph)), {(Zn-OP-P-SO)PdMe(L)}4 (D, L = pyridine or 4-tBu-pyridine, [OP-P-SO]3- = P(4-tBu-Ph)(2-PO32--5-Me-Ph)(2-SO3-</su ...[more]

PMID: 32707738

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