Strong and Tough Supramolecular Covalent Adaptable Networks with Room‐Temperature Closed‐Loop Recyclability

Advanced Materials, Год журнала: 2022, Номер 35(7)

Опубликована: Ноя. 11, 2022

Development of closed-loop chemically recyclable plastics (CCRPs) that can be widely used in daily life a fundamental solution to the global plastic waste crisis. Hence, it is great significance develop easy-to-recycle CCRPs possess superior or comparable material properties commodity plastics. Here, novel dual crosslinked CCRP, namely, supramolecular covalent adaptable networks (supra-CANs), reported, which not only displays mechanical higher than strong and tough polycarbonate, but also exhibits excellent solvent resistance as thermosets. The supra-CANs are constructed by introducing reversible noncovalent crosslinks into dynamic polymer networks, resulting highly stiff thermosets exhibit thermoplastic-like ductile behaviors well reprocessability rehealability. In contrast, analogs do have (CANs) show elastomeric with significantly decreased strength. Importantly, developed CANs converted back initial monomers high yields purity at room temperature, even additives, enables sustainable polymer-monomer-polymer circulation. This work provides new design principles for high-performance polymers substitutes conventional

Язык: Английский

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Closed‐Loop Recycling of Poly(Imine‐Carbonate) Derived from Plastic Waste and Bio‐based Resources

Angewandte Chemie International Edition, Год журнала: 2022, Номер 61(43)

Опубликована: Сен. 8, 2022

Closed-loop recycling of polymers represents the key technology to convert plastic waste in a sustainable fashion. Efficient chemical and upcycling strategies are thus highly sought-after establish circular economy. Here, we present selective depolymerization polycarbonate by employing vanillin derivative as bio-based feedstock. The resulting di-vanillin carbonate monomer was used combination with various amines construct library reprocessable poly(imine-carbonate)s, which show tailor-made thermal mechanical properties. These novel poly(imine-carbonate)s exhibit excellent recyclability under acidic energy-efficient conditions. This allows recovery monomers high yields purity for immediate reuse, even when mixed commodity plastics. work provides exciting new insights design produced minimal environmental impact.

Язык: Английский

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Depolymerization within a Circular Plastics System

Chemical Reviews, Год журнала: 2024, Номер 124(5), С. 2617 - 2650

Опубликована: Фев. 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.

Язык: Английский

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

Angewandte Chemie International Edition, Год журнала: 2023, Номер 62(29)

Опубликована: Апрель 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.

Язык: Английский

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Recyclable, Degradable, and Fully Bio-Based Covalent Adaptable Polymer Networks Enabled by a Dynamic Diacetal Motif

ACS Sustainable Chemistry & Engineering, Год журнала: 2023, Номер 11(7), С. 3065 - 3073

Опубликована: Фев. 8, 2023

Covalent adaptable networks (CANs), which can reconfigure on-demand under photo- or thermal stimuli, have recently been pursued as an alternative to the traditional thermosetting polymers. While these materials demonstrated excellent recyclability and reprocessability, majority of them reported date are based on non-renewable resources. Meanwhile, material recycling highly counts collection system, any that inevitably escape from system will eventually go environment, challenging nature's ability break down materials. Therefore, CAN possess both degradability desirable. In this work, we seek simultaneously address recyclability, renewability, Spiro diacetal building blocks derived bio-based benzaldehyde erythritol then subjected curing process using epoxy soybean oil crosslinkers, yielding fully biobased Owing dynamic degradable features acetal motifs, our exhibit good acid degradability, degraded products reusable for preparation new CANs. addition, by tuning steric hindrance adjacent reactive phenol site, able control mechanical properties CANs different benzaldehydes (vanillin, ethyl vanillin, syringaldehyde). The outcome current research provides a strategy design recyclable CANs, extend development

Язык: Английский

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Mechanically Robust, Recyclable, and Self‐Healing Polyimine Networks

Advanced Science, Год журнала: 2023, Номер 10(19)

Опубликована: Апрель 23, 2023

To achieve energy saving and emission reduction goals, recyclable healable thermoset materials are highly attractive. Polymer copolymerization has been proven to be a critical strategy for preparing high-performance polymeric materials. However, it remains huge challenge develop Here, polyimine dynamic networks based on two monomers with bulky pendant groups, which not only displayed mechanical properties higher than the strong tough polymers, e.g., polycarbonate, but also excellent self-repairing capability recyclability as thermosets developed. Owing stability of conjugation effect by aromatic benzene rings, final far more stable reported counterparts, exhibiting hydrolysis resistance under both alkaline condition most organic solvents. These structure can completely depolymerized into recovery in an acidic aqueous solution at ambient temperature. Resulting from units, this method allows exchange reactions vitrimer easily within minutes self-healing function. Moreover, introduction trifluoromethyl diphenoxybenzene backbones significantly increases tensile This work provides effective fabricating polymer multiple functions.

Язык: Английский

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Closed-loop recycling of tough epoxy supramolecular thermosets constructed with hyperbranched topological structure

Nature Communications, Год журнала: 2024, Номер 15(1)

Опубликована: Июнь 7, 2024

The regulation of topological structure covalent adaptable networks (CANs) remains a challenge for epoxy CANs. Here, we report strategy to develop strong and tough supramolecular thermosets with rapid reprocessability room-temperature closed-loop recyclability. These were constructed from vanillin-based hyperbranched resin (VanEHBP) through the introduction intermolecular hydrogen bonds dual dynamic bonds, as well formation intramolecular cavities. structures confer remarkable energy dissipation capability thermosets, leading high toughness strength. Due imine exchange reversible noncovalent crosslinks, can be rapidly effectively reprocessed at 120 °C within 30 s. Importantly, efficiently depolymerized room temperature, recovered materials retain structural integrity mechanical properties original samples. This may employed design tough, recyclable practical applications.

Язык: Английский

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Closed‐Loop Recyclable High‐Performance Polyimine Aerogels Derived from Bio‐Based Resources

Advanced Materials, Год журнала: 2022, Номер 35(8)

Опубликована: Дек. 10, 2022

Organic aerogels are an intriguing class of highly porous and ultralight materials which have found widespread applications in thermal insulation, energy storage, chemical absorption. These fully cross-linked polymeric networks, however, pose environmental concerns as they typically made from fossil-based feedstock the recycling back to their original monomers is virtually impossible. In addition, organic suffer low stability potential fire hazard. To overcome these obstacles create next-generation aerogels, a set polyimine containing reversible bonds can selectively be cleaved on demand prepared. As precursors, different primary amines cyclophosphazene derivatives bio-based reagents (vanillin 4-hydroxybenzaldehyde) elevate reduce impact used. The resulting exhibit shrinkage, high porosity, large surface area, well pronounced flame resistance. More importantly, show excellent recyclability under acidic conditions with monomer recovery yields purities. This approach allows for preparation fresh retrieved building blocks, thus demonstrating efficient closed-loop recycling. high-performance, recyclable, pave way advanced sustainable superinsulating materials.

Язык: Английский

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Chemically Recyclable and Upcyclable Epoxy Resins Derived from Vanillin

ACS Sustainable Chemistry & Engineering, Год журнала: 2023, Номер 11(22), С. 8308 - 8316

Опубликована: Май 22, 2023

Epoxy resins constitute a very significant portion of all high-performance plastics due to their excellent thermal and mechanical properties that appear in wide range applications. Nevertheless, traditional epoxy networks show limitations regarding chemical recycling covalently crosslinked structures. The current methods recycle are not indeed through sustainable ways, but this issue could be solved by developing smart monomers with functional groups, which can switched between polymerized depolymerized states. Herein, we developed two bio-based liquid based on vanillin structures containing aldehyde, acetal, oxirane-ring functionalities. These were solvent-free conditions using commercially available diamines, resulting double-dynamic imine-acetal-containing thermosets. combine the systems dynamic polymers. Most importantly, such thermosets fully into vanillin, reused for preparation original monomers, mixture well-defined polyols, was upcycled polyurethane.

Язык: Английский

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

Angewandte Chemie International Edition, Год журнала: 2023, Номер 63(7)

Опубликована: Дек. 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

Язык: Английский

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