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Isoselective Lactide Ring Opening Polymerisation using [2]Rotaxane Catalysts.

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 (P_i =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.

SUBMITTER: Lim JYC

PROVIDER: S-EPMC6519244 | biostudies-literature | 2019 Apr

REPOSITORIES: biostudies-literature

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Isoselective Lactide Ring Opening Polymerisation using [2]Rotaxane Catalysts.

Lim Jason Y C JYC Yuntawattana Nattawut N Beer Paul D PD Williams Charlotte K CK

Angewandte Chemie (International ed. in English) 20190328 18

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 (P<sub>i</sub> =0.8, 298 K) without requiring any chiral additives and enchain by a chain e ...[more]

PMID: 30861303

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