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Updated: Jan 27, 2026

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Published on: May 13, 2018
Isoselective Lactide Ring Opening Polymerisation using [2]Rotaxane Catalysts
Jason Y C Lim1,2, Nattawut Yuntawattana1, Paul D Beer1
1Department of Chemistry, University of Oxford, Chemistry Research Laboratory, Mansfield Road, Oxford, OX1 3TA, UK.
Abstract:
Polylactide (PLA) is a fully biodegradable and recyclable plastic, produced from a bio-derived monomer: it is a circular economy plastic. Its properties depend upon its stereochemistry and isotactic PLA shows superior thermal-mechanical performances. Here, a new means to control tacticity by exploiting rotaxane conformational dynamism is described. Dynamic achiral [2]rotaxanes can show high isoselectivity (Pi =0.8, 298 K) without requiring any chiral additives and enchain by a chain end control mechanism. The organocatalytic dynamic stereoselectivity is likely applicable to other small-molecule and polymerization catalyses.
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