Efficient chemical recycling of poly(L-lactic acid) via either alcoholysis to alkyl lactate or thermal depolymerization to L-lactide promoted by Zn(II) catalysts

IF 5 2区材料科学 Q1 MATERIALS SCIENCE, CHARACTERIZATION & TESTING

Polymer Testing Pub Date : 2025-02-01 DOI:10.1016/j.polymertesting.2025.108727

Maria Gentile , Licia Gaeta , Stefano Brenna , Claudio Pellecchia

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引用次数: 0

Abstract

Poly(lactic acid) (PLA), a commercially fully bio-based and biodegradable polymer, stands out as a sustainable alternative to commodity plastics. Its current end-of-life management involves composting, but chemical recycling would be more appropriate for a circular economy model. Here we report two very efficient chemical recycling pathways for commercial high molar mass and highly crystalline PLA samples, both ones promoted by different imidazole[1,5-a]pyrid-3-yl)phenolate Zn(II) catalysts: (i) alcoholysis was easily achieved by simply treating the polymer samples in boiling methanol in the presence of 1 % Zn(II) catalyst, resulting in up to 99 % yield and selectivity in methyl lactate; and (ii) chemical recycling to the monomer was achieved by heating the polymer samples at 180 °C under vacuum or in a nitrogen flow in the presence of 0.1 % Zn(II) catalyst and a highly boiling alcohol, resulting in up to 99 % yield of L-lactide, having high chemical and steric purity, which could be repolymerized without any further purification.

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来源期刊

Polymer Testing 工程技术-材料科学：表征与测试

CiteScore

10.70

自引率

5.90%

发文量

328

审稿时长

44 days

期刊介绍： Polymer Testing focuses on the testing, analysis and characterization of polymer materials, including both synthetic and natural or biobased polymers. Novel testing methods and the testing of novel polymeric materials in bulk, solution and dispersion is covered. In addition, we welcome the submission of the testing of polymeric materials for a wide range of applications and industrial products as well as nanoscale characterization. The scope includes but is not limited to the following main topics: Novel testing methods and Chemical analysis • mechanical, thermal, electrical, chemical, imaging, spectroscopy, scattering and rheology Physical properties and behaviour of novel polymer systems • nanoscale properties, morphology, transport properties Degradation and recycling of polymeric materials when combined with novel testing or characterization methods • degradation, biodegradation, ageing and fire retardancy Modelling and Simulation work will be only considered when it is linked to new or previously published experimental results.