N‐Heterocyclic Carbene‐Based Zinc Complexes: Same Precursors for Different Lactide Ring‐Opening Polymerization Mechanisms.
نویسندگان
چکیده
Two zinc complexes bearing NHC ligands were synthesized and fully characterized by NMR spectroscopy. Their behavior in the Ring-Opening Polymerization (ROP) of lactides was investigated under several conditions reaction. They showed to be efficient initiators, producing polylactides with molecular weights depending on cocatalysts. Microstructural analysis poly(rac-LA) 1H spectroscopy revealed a slightly enriched-heterotactic PLAs Pr values up 0.66. Inspection kinetic parameters for L-LA rac-LA allowed compare kobs studied 1 2 different conditions, that propagations present usual pseudo-first-order dependence monomer concentration. Hence, some reactivity studies carried out, addressed unravel nature active species polymerization processes conducted presence catalytic systems, namely alone combination neutral or ionic
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ژورنال
عنوان ژورنال: Chemcatchem
سال: 2022
ISSN: ['1867-3899', '1867-3880']
DOI: https://doi.org/10.1002/cctc.202200962