N-Heterocyclic carbene iron complexes catalyze the ring-opening polymerization of lactide.

ABSTRACT: Poly(lactic acid), PLA, which holds great promise as a biodegradable substitute of fossil resource-derived polyolefins, is industrially produced by the ring-opening polymerization of lactide using a potentially harmful tin catalyst. Based on mechanistic insights into the reaction of N-heterocyclic carbene (NHC) iron complexes with carbonyl substrates, we surmised and demonstrate here that such complexes are excellent catalysts for the bulk polymerization of lactide. We show that an iron complex with a triazolylidene NHC ligand is active at lactide/catalyst ratios of up to 10 000 : 1, produces polylactide with relatively high number-average molecular weights (up to 50 kg mol^-1) and relatively narrow dispersity (Đ ∼ 1.6), and features an apparent polymerization rate constan

SUBMITTER: Nylund PVS 

PROVIDER: S-EPMC8819372 | biostudies-literature | 2022 Feb

REPOSITORIES: biostudies-literature