Review of polymer technologies for improving the recycling and upcycling efficiency of plastic waste

Chemosphere, Journal Year: 2023, Volume and Issue: 320, P. 138089 - 138089

Published: Feb. 6, 2023

Human society has become increasingly reliant on plastic because it allows for convenient and sanitary living. However, recycling rates are currently low, which means that the majority of waste ends up in landfills or ocean. Increasing upcycling is a critical strategy addressing issues caused by pollution, but there several technical limitations to overcome. This article reviews advancements polymer technology aim improve efficiency waste. In food packaging, natural polymers with excellent gas barrier properties self-cleaning abilities have been introduced as environmentally friendly alternatives existing materials reduce food-derived contamination. Upcycling valorization approaches emerged transform into high-value-added products. Recent development recyclable high-performance plastics include design super engineering thermoplastics chemical bonds thermosets make them biodegradable. Further research needed develop more cost-effective scalable technologies address pollution problem through sustainable upcycling.

Language: Английский

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Catalytic disconnection of C–O bonds in epoxy resins and composites

Nature, Journal Year: 2023, Volume and Issue: 617(7962), P. 730 - 737

Published: April 26, 2023

Fibre-reinforced epoxy composites are well established in regard to load-bearing applications the aerospace, automotive and wind power industries, owing their light weight high durability. These based on thermoset resins embedding glass or carbon fibres1. In lieu of viable recycling strategies, end-of-use composite-based structures such as turbine blades commonly landfilled1-4. Because negative environmental impact plastic waste5,6, need for circular economies plastics has become more pressing7,8. However, is no trivial matter1-4. Here we report a transition-metal-catalysed protocol recovery polymer building block bisphenol A intact fibres from composites. Ru-catalysed, dehydrogenation/bond, cleavage/reduction cascade disconnects C(alkyl)-O bonds most common linkages polymer. We showcase application this methodology relevant unmodified amine-cured commercial composites, including shell blade. Our results demonstrate that chemical approaches achievable.

Language: Английский

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Recycling of Thermoset Materials and Thermoset-Based Composites: Challenge and Opportunity

Polymers, Journal Year: 2022, Volume and Issue: 14(19), P. 4153 - 4153

Published: Oct. 4, 2022

Thermoset materials and their composites are characterized by a long life cycle with main applications in aircrafts, wind turbines constructions as insulating materials. Considering the importance of recovery valorization these at end-of-life, avoiding landfilling, interest concerning recycling grows continuously. The thermoset composites, to be successfully recovered valorized, must degrade three-dimensional structures recover mono-oligomers and/or fillers. could through thermal treatment different temperatures (for example, above 1000 °C for incineration, ca. 500 oxidation/combustion organic constituents, etc.), chemical degradation catalyst, irradiation or without presence water, alcohol, etc., mechanical recycling, obtaining fine particles that useful filler reinforcement additives. Among methods, this mini-review focuses on formulation method innovative in-build recyclability, i.e., having links degraded on-demand containing dynamic covalent bonds have re-processable recyclable thermoset. This issue considered future perspective developing novel aim review is get an overview state art most commonly used recovering valuable reinforcing fibers. Additionally, work, we also report not only known routes thermoset-based but new formulating strategies producing thermosets built-in chemical-triggered links. guide educational purposes students specialized technicians polymer production recycling.

Language: Английский

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Depolymerization within a Circular Plastics System

Chemical Reviews, Journal Year: 2024, Volume and Issue: 124(5), P. 2617 - 2650

Published: Feb. 22, 2024

The societal importance of plastics contrasts with the carelessness which they are disposed. Their superlative properties lead to economic and environmental efficiency, but linearity puts climate, human health, global ecosystems at risk. Recycling is fundamental transitioning this linear model into a more sustainable, circular economy. Among recycling technologies, chemical depolymerization offers route virgin quality recycled plastics, especially when valorizing complex waste streams poorly served by mechanical methods. However, exists in interlinked system end-of-life fates, complementarity each approach key environmental, economic, sustainability. This review explores recent progress made five commercial polymers: poly(ethylene terephthalate), polycarbonates, polyamides, aliphatic polyesters, polyurethanes. Attention paid not only catalytic technologies used enhance efficiencies also interrelationship other systemic constraints imposed Novel polymers, designed for depolymerization, concisely reviewed terms their underlying chemistry potential integration current plastic systems.

Language: Английский

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Bio-based hyperbranched epoxy resins: synthesis and recycling

Chemical Society Reviews, Journal Year: 2023, Volume and Issue: 53(2), P. 624 - 655

Published: Dec. 18, 2023

This review provides a comprehensive overview of the synthesis, degradation, and recycling bio-based hyperbranched epoxy resins.

Language: Английский

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Additive manufacturing for sustainability and circular economy: needs, challenges, and opportunities for 3D printing of recycled polymeric waste

Materials Today Sustainability, Journal Year: 2023, Volume and Issue: 24, P. 100529 - 100529

Published: Sept. 5, 2023

Polymer-based product usage rapidly increases globally, leading to severe ecological, social, environmental, health, and economic impacts. There has been an international push for solutions sustainable production, consumption, end-of-life plastics combat these issues. Moreover, additive manufacturing (AM) or 3D printing (3DP) processes provide rapid fabrication of functional parts in lesser time, lower lead times, research development costs. Due reasons, are now being utilized different industrial sectors, including aerospace, automotive, biomedical, sports, food, electronics, construction. The circular economy concept integrated with AM can deliver a synergic impact new life discarded polymeric distributed recycling manufacturing. With the adoption proper techniques, be used widely reuse polymer wastes turn them into valuable products. It much higher levels at very low cost targeted applications. Therefore, this study, comprehensive literature review is performed outline guidelines model recycled polymers based on reviewed literature. This study delivers insight into; commodity their uses, challenges recycling, approaches, polymers.

Language: Английский

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The Key to Solving Plastic Packaging Wastes: Design for Recycling and Recycling Technology

Polymers, Journal Year: 2023, Volume and Issue: 15(6), P. 1485 - 1485

Published: March 16, 2023

Confronted with serious environmental problems caused by the growing mountains of plastic packaging waste, prevention and control waste has become a major concern for most countries. In addition to recycling wastes, design can effectively prevent from turning into solid at source. The reasons are that extend life cycle increase values waste; moreover, technologies helpful improving properties recycled plastics expanding application market materials. This review systematically discussed present theory, practice, strategies, methods extracted valuable advanced ideas successful cases. Furthermore, development status automatic sorting methods, mechanical individual mixed as well chemical thermoplastic thermosetting were comprehensively summarized. combination front-end back-end accelerate transformation industry an unsustainable model economic then achieve unity economic, ecological, social benefits.

Language: Английский

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Photocatalysis as an Effective Tool for Upcycling Polymers into Value‐Added Molecules

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(29)

Published: April 13, 2023

Abstract Shaping a sustainable future is closely tied to the development of advanced plastic recycling technologies. As global rates remain low, lion's share post‐consumer plastics either incinerated or disposed in landfills. This unbalanced waste management not only poses severe environmental risks, but also entails an irrevocable loss chemical resources that are embedded synthetic polymers. To give new life, series photocatalytic methods has recently been reported convert polymers directly into value‐added organic molecules. These approaches operate at ambient temperature, show high reactivity/selectivity, and provide alternative reaction pathways as compared thermal depolymerizations. Minireview highlights scientific breakthroughs upcycling through state‐of‐the‐art photocatalysis under environmentally benign conditions.

Language: Английский

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High-Performance Recyclable and Malleable Epoxy Resin with Vanillin-Based Hyperbranched Epoxy Resin Containing Dual Dynamic Bonds

ACS Sustainable Chemistry & Engineering, Journal Year: 2023, Volume and Issue: 11(30), P. 11077 - 11087

Published: July 18, 2023

Dynamic covalent polymer networks represent new opportunities in the design of sustainable epoxy resins due to their excellent malleability and reprocessability; however, adaptable network is usually accompanied by low glass transition temperature, poor creep resistance, mechanical brittleness. Herein, we demonstrate a vanillin-based hyperbranched resin (VEHBP) containing disulfide imine dynamic bonds for recyclable malleable with high temperature (Tg), significantly improved properties. The 5%VEHBP exhibited 175 °C 130 34.1, 19.7, 173.3% increase tensile strength, storage modulus, toughness respectively, compared neat resin. Meanwhile, topological structure VEHBP complemented dual endowed these materials self-healing ability, reprocessability, degradability, which represents an important step toward fabrication high-performance networks.

Language: Английский

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New Advances in Covalent Network Polymers via Dynamic Covalent Chemistry

Chemical Reviews, Journal Year: 2024, Volume and Issue: 124(12), P. 7829 - 7906

Published: June 3, 2024

Covalent network polymers, as materials composed of atoms interconnected by covalent bonds in a continuous network, are known for their thermal and chemical stability. Over the past two decades, these have undergone significant transformations, gaining properties such malleability, environmental responsiveness, recyclability, crystallinity, customizable porosity, enabled development integration dynamic chemistry (DCvC). In this review, we explore innovative realm polymers focusing on recent advances achieved through application DCvC. We start examining history fundamental principles DCvC, detailing its inception core concepts noting key role reversible bond formation. Then reprocessability DCvC is thoroughly discussed, starting from milestones that marked evolution progressing to current trends applications. The influence crystallinity then reviewed, covering diversity, synthesis techniques, functionalities. concluding section, address challenges faced field speculates potential future directions.

Language: Английский

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