Recyclable and (Bio)degradable Polyesters in a Circular Plastics Economy

Chemical Reviews, Journal Year: 2024, Volume and Issue: 124(7), P. 4393 - 4478

Published: March 22, 2024

Polyesters carrying polar main-chain ester linkages exhibit distinct material properties for diverse applications and thus play an important role in today's plastics economy. It is anticipated that they will even greater tomorrow's circular economy focuses on sustainability, thanks to the abundant availability of their biosourced building blocks presence bonds can be chemically or biologically cleaved demand by multiple methods bring about more desired end-of-life plastic waste management options. Because this potential promise, there have been intense research activities directed at addressing recycling, upcycling biodegradation existing legacy polyesters, designing biorenewable alternatives, redesigning future polyesters with intrinsic chemical recyclability tailored performance rival commodity are either petroleum based and/or hard recycle. This review captures these exciting recent developments outlines challenges opportunities. Case studies poly(lactic acid), poly(3-hydroxyalkanoate)s, poly(ethylene terephthalate), poly(butylene succinate), poly(butylene-adipate presented, emerging recyclable comprehensively reviewed.

Language: Английский

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Chemical Recycling of Commercial Poly(l-lactic acid) to l-Lactide Using a High-Performance Sn(II)/Alcohol Catalyst System

Journal of the American Chemical Society, Journal Year: 2023, Volume and Issue: 145(36), P. 19840 - 19848

Published: Sept. 1, 2023

Poly(l-lactic acid) (PLLA) is a leading commercial polymer produced from biomass, showing useful properties for plastics and fiber applications; after use, it compostable. One area improvement postconsumer waste PLLA chemical recycling to monomer (CRM), i.e., the formation of l-lactide (l-LA) plastic. This process currently feasible at high reaction temperatures shows low catalytic activity accompanied, in some cases, by side reactions, including epimerization. Here, Sn(II) catalyst, applied with nonvolatile alcohol, enables highly efficient CRM yield l-LA excellent purity (92% yield, >99% theoretical max.). The depolymerization performed using neat films (160 °C) under nitrogen flow or vacuum. operates outstanding activity, achieving turnover frequencies which are up 3000× higher than previously catalysts loadings 6000× lower catalysts. catalyst system achieves TOF = 3000 h–1 0.01 mol % 1:10,000 catalyst:PLLA loading. plastic packaging (coffee cup lids) produces pure selectivity. new (Sn + alcohol) can itself be recycled four times different "batch degradations" maintains its productivity,

Language: Английский

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Designed to Degrade: Tailoring Polyesters for Circularity

Chemical Reviews, Journal Year: 2024, Volume and Issue: 124(13), P. 8473 - 8515

Published: June 27, 2024

A powerful toolbox is needed to turn the linear plastic economy into circular. Development of materials designed for mechanical recycling, chemical and/or biodegradation in targeted end-of-life environment are all necessary puzzle pieces this process. Polyesters, with reversible ester bonds, already forerunners circularity: poly(ethylene terephthalate) (PET) most recycled material suitable and while common aliphatic polyesters biodegradable under favorable conditions, such as industrial compost. However, circular design needs be further tailored different options enable recycling greener conditions rapid enough even less environmental conditions. Here, we discuss molecular polyester chain targeting enhancement circularity by incorporation more easily hydrolyzable additional dynamic or degradation catalyzing functional groups part chain. The utilization replacement current volume plastics also reviewed well embedment green catalysts, enzymes matrices facilitate

Language: Английский

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Ring‐opening Polymerization of Enantiopure Bicyclic Ether‐ester Monomers toward Closed‐loop Recyclable and Crystalline Stereoregular Polyesters via Chemical Upcycling of Bioplastic

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(23)

Published: April 5, 2023

Although great successes have been achieved, the preparation of closed-loop recyclable polyesters with high working temperatures still remains as a big challenge. Herein, we present syntheses series enantiopure bicyclic ether-ester monomers by upcycling poly(3-hydroxybutyrate) bioplastic. The "living"/controlled ring-opening polymerizations these to produce stereoregular controlled molecular weights and well-defined chain ends were achieved. effects stereoconfiguration substituent on polymerization kinetics thermodynamics well thermal properties resultant investigated. Of note, are semi-crystalline materials melting up 176 °C, even higher than commodity polyolefin plastics. These can be depolymerized back recover pristine monomers, thus successfully establishing life cycle.

Language: Английский

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Constructing magnetic metal doping carbon micro-particles with columnar structure via carbonization of waste masks for microwave absorption

Polymer, Journal Year: 2024, Volume and Issue: 294, P. 126739 - 126739

Published: Jan. 25, 2024

Language: Английский

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Recycling of Epoxy Resins with Degradable Structures or Dynamic Cross-Linking Networks: A Review

Industrial & Engineering Chemistry Research, Journal Year: 2024, Volume and Issue: 63(12), P. 5005 - 5027

Published: March 19, 2024

Traditional epoxy resins (EPR), represented by bisphenol A type, have high chemical bond energy, low polarity, and stable properties. The topological structure after curing makes EPR impossible for convenient recycling through heating or dissolution like thermoplastics. This results in traditional having no advantage of efficient recycling, both molecular the combination morphology polymer chains. However, introducing degradable dynamically cross-linked structures into to modify their will bring good special responsiveness, with expectation achieve while maintaining original performance. paper reviews research progress cross-linkable such as ester, acetal, similar structures, Schiff bases, disulfide bonds, Diels–Alder addition structures. highlights impact these themselves on recycling. We discussed potential structures' findings small-molecule organic chemistry

Language: Английский

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Modulating Polymerization Behaviors of Ether–Ester Monomers and Physicochemical Properties of Poly(ether-alt-ester)s by Heteroatom Substitutions

Macromolecules, Journal Year: 2024, Volume and Issue: 57(3), P. 869 - 879

Published: Jan. 24, 2024

The design of cyclic monomers is crucial for the development polymers with ideal thermal and mechanical properties by ring-opening polymerization. Herein, we provide a systematic investigation into thio-modification effects on polymerization behavior ether–ester final corresponding poly(ether-alt-ester)s. position significantly affected thermodynamics thus could regulate ceiling temperature (Tc). O-to-S substitutions in monomer′s ether/ester sites would increase α-H acidity, catalytic system strictly determined chain initiation process as well chain-end groups. Density functional theory calculations experimental studies revealed that at ester site accelerate under same conditions, thanks to high reactivity thioester group strong nucleophilicity end. resulting poly(ether-alt-ester)s exhibited crystallinity, precisely tunable physicochemical properties, recyclability, high-density polyethylene-like which exemplifies potential heteroatom modification modulating poly(ether-alt-ester)′s properties. This detailed structure–(de)polymerizability structure–property relationships will inspire future monomer toward performance.

Language: Английский

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Torsional Strain Enabled Ring‐Opening Polymerization towards Axially Chiral Semiaromatic Polyesters with Chemical Recyclability

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(13)

Published: Feb. 15, 2024

Abstract The development of new chemically recyclable polymers via monomer design would provide a transformative strategy to address the energy crisis and plastic pollution problem. Biaryl‐fused cyclic esters were targeted generate axially chiral polymers, which impart material performance. To overcome non‐polymerizability biaryl‐fused DBO, ester Me‐DBO installed with dimethyl substitution was prepared enable its polymerizability enhancing torsional strain. Impressively, readily went through well‐controlled ring‐opening polymerization, producing polymer P(Me‐DBO) high glass transition temperature ( T g >100 °C). Intriguingly, mixing these complementary enantiopure containing axial chirality promoted transformation from amorphous crystalline material, affording semicrystalline stereocomplex melting more than 300 °C. capable depolymerizing back in efficiency, highlighting an excellent recyclability.

Language: Английский

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Biomass-derived closed-loop recyclable chemically crosslinked polymer composites for green soft electronics

Chemical Engineering Journal, Journal Year: 2024, Volume and Issue: 488, P. 150818 - 150818

Published: March 29, 2024

Language: Английский

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Closed-loop recyclable polymers: from monomer and polymer design to the polymerization–depolymerization cycle

Chemical Society Reviews, Journal Year: 2024, Volume and Issue: 53(19), P. 9609 - 9651

Published: Jan. 1, 2024

We present the state-of-the-art of circular polymers based on monomer and polymer design reversible ring-opening addition polymerization reactions without involvement other reactants.

Language: Английский

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