Acid‐Cleavable Aromatic Polymers for the Fabrication of Closed‐Loop Recyclable Plastics with High Mechanical Strength and Excellent Chemical Resistance

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 63(7)

Published: Dec. 22, 2023

Although closed-loop recycling of dynamic covalent bond-based plastics does not require catalysts, their mechanical strength and chemical stability remain a major concern. In this study, recyclable poly(aryl imine) (PAI) with high excellent resistance are fabricated by copolymerizing aromatic amines aldehydes through imine bonds. The resulting PAI plastic tensile 58.2 MPa exhibits in acidic basic aqueous solutions various organic solvents. can be depolymerized mixed solvent tetrahydrofuran (THF)/HCl solution the dissociation bonds, monomers facilely recovered purity isolated yields due to solubility difference between selective efficient also realized monomer conversion because hydrolysis generates amines. used re-fabricate original plastics. This selectively from complicated polymer waste streams mild depolymerization conditions its most

Language: Английский

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Performance‐Advantaged Stereoregular Recyclable Plastics Enabled by Aluminum‐Catalytic Ring‐Opening Polymerization of Dithiolactone

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(24)

Published: April 14, 2023

Chemically recyclable polymers that can depolymerize into their constituent monomers are attractive candidates to replace non-recyclable petroleum-derived plastics. However, the physical properties and mechanical strengths of depolymerizable commonly insufficient for practical applications. Here we demonstrate by proper ligand design modification, aluminum complexes catalyse stereoretentive ring-opening polymerization dithiolactone, yielding highly isotactic polythioesters with molar masses up 45.5 kDa. This material form crystalline stereocomplex a Tm 94.5 °C, exhibits performances comparable petroleum-based low density polyethylene. Exposure polythioester precatalyst used synthesized it resulted in depolymerization pristine chiral dithiolactone. Experimental computational studies suggest have appropriate binding affinity sulfide propagating species, thereby avoiding catalyst poisoning minimizing epimerization reactions, which has not been accessible using other metal catalysts. Overall, catalysis provides access performance-advantaged stereoregular plastics as promising alternative petrochemical plastics, thus incentivizing improved plastic sustainability.

Language: Английский

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Chemically Recyclable Polyethylene‐like Sulfur‐Containing Plastics from Sustainable Feedstocks

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(13)

Published: Feb. 4, 2023

The green revolution in plastics should be accelerated due to growing sustainability concerns. Here, we develop a series of chemically recyclable polymers from the first reported cascade polymerization H2 O, COS, and diacrylates. In addition abundant feedstocks, method is efficient air-tolerant, uses common organic bases as catalysts, yields with high molecular weights under mild conditions. Such polymers, structurally like polyethylene low-density in-chain polar groups, manifest impressive toughness ductility comparable high-density polyethylene. ester group acts breaking point, enabling these undergo chemical recycling through two loops. structures properties also have an immeasurably expanded range owing versatility our method. readily available raw materials, facile synthesis, performance make promising prospects sustainable materials practice.

Language: Английский

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A recyclable polyester library from reversible alternating copolymerization of aldehyde and cyclic anhydride

Nature Communications, Journal Year: 2023, Volume and Issue: 14(1)

Published: Sept. 5, 2023

Our society is pursuing chemically recyclable polymers to accelerate the green revolution in plastics. Here, we develop a polyester library from alternating copolymerization of aldehyde and cyclic anhydride. Although these two monomer sets have little or no thermodynamic driving force for homopolymerization, their demonstrates unexpected characteristics. In addition readily available monomers, method performed under mild conditions, uses common Lewis/Brønsted acids as catalysts, achieves facile tuning structure using distinct sets, yields 60 polyesters. Interestingly, exhibits chemical reversibility attributed its relatively low enthalpy, which makes resulting polyesters perform closed-loop recycling monomers at high temperatures. This study provides modular, efficient, synthesis sustainable monomers.

Language: Английский

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Redesigned Nylon 6 Variants with Enhanced Recyclability, Ductility, and Transparency

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(17)

Published: Feb. 29, 2024

Abstract Geminal ( gem −) disubstitution in heterocyclic monomers is an effective strategy to enhance polymer chemical recyclability by lowering their ceiling temperatures. However, the effects of specific substitution patterns on monomer's reactivity and resulting polymer's properties are largely unexplored. Here we show that, systematically installing ‐dimethyl groups onto ϵ‐caprolactam (monomer nylon 6) from α ϵ positions, both redesigned lactam ‐nylon 6’s highly sensitive position, with ranging non‐polymerizable polymerizable inferior far superior parent 6. Remarkably, 6 ‐dimethyls substituted at γ position amorphous optically transparent, a higher T g (by 30 °C), yield stress 1.5 MPa), ductility 3×), lower depolymerization temperature 60 °C) than conventional

Language: Английский

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