New Advances in Covalent Network Polymers via Dynamic Covalent Chemistry

Chemical Reviews, Год журнала: 2024, Номер 124(12), С. 7829 - 7906

Опубликована: Июнь 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.

Язык: Английский

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Mismatched Supramolecular Interactions Facilitate the Reprocessing of Super‐Strong and Ultratough Thermoset Elastomers

Advanced Materials, Год журнала: 2024, Номер 36(28)

Опубликована: Май 17, 2024

Thermoset elastomers have been extensively applied in many fields because of their excellent mechanical strengths and durable characteristics, such as an chemical resistance. However, the context environmental issues, nonrecyclability thermosets has become a major barrier to further development these materials. Here, well-tailored strategy is reported solve this problem by introducing mismatched supramolecular interactions (MMSIs) into covalently cross-linked poly(urethane-urea) network with dynamic acylsemicarbazide moieties. The MMSIs significantly strengthen toughen thermoset elastomer effectively dissipating energy resisting external stress. In addition, recycling efficiency improved 2.7-fold due superior reversibility MMSIs. optimized features outstanding including ultrahigh tensile strength (110.8 MPa), unprecedented toughness (1245.2 MJ m

Язык: Английский

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Robust, waterproof, and degradable cellulose-based polyimine vitrimer for plastic replacement

Chemical Engineering Journal, Год журнала: 2023, Номер 471, С. 144501 - 144501

Опубликована: Июнь 28, 2023

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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Direct and Catalyst-Free Ester Metathesis Reaction for Covalent Adaptable Networks

Journal of the American Chemical Society, Год журнала: 2023, Номер 145(38), С. 20927 - 20935

Опубликована: Сен. 15, 2023

Thermosetting polymers possess excellent environmental resistance and mechanical properties but cannot be reprocessed due to their covalently cross-linked structures. Recycling of thermosets via the implantation dynamic covalent bonds offers a promising solution. Here, we report direct catalyst-free ester metathesis N-acyloxyphthalimide (NAPI) at about 100 °C without requirement hydroxyl groups its utilization for fabrication adaptable networks (CANs). NAPI has interesting sigmoid kinetics with fast exchange rate, which proceeds free radical chain mechanism, guaranteeing associative under rather low dissociation. The bifunctional molecule as both precursor substrate is key dissociatively initiated (DAssociative) mechanism kinetic behavior. Based on efficient metathesis, polyester networks, poly(N-acyloxyphthalimides) (PNAPIs), show malleability. Notably, PNAPIs exhibit exceptional solvent stability elevated temperatures owing unique DAssociative suggesting exciting opportunities designing recyclable thermosetting polymers.

Язык: Английский

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A strong, biodegradable, and closed-loop recyclable bamboo-based plastic substitute enabled by polyimine covalent adaptable networks

Chemical Engineering Journal, Год журнала: 2023, Номер 477, С. 146952 - 146952

Опубликована: Окт. 27, 2023

Язык: Английский

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Mechanically Robust Reversibly Cross‐Linked Polymers with Closed‐Loop Recyclability for Use in Flexible Printed Circuit Boards

Advanced Functional Materials, Год журнала: 2024, Номер 34(34)

Опубликована: Апрель 26, 2024

Abstract It remains a huge challenge to efficiently recycle the printed circuit boards (PCBs) because of diversity and complexity PCBs in terms material composition. The recycling highly depends on design polymers that make up polymer substrates conductive pastes. Herein, closed‐loop recyclable plastics for use as preparation pastes are fabricated by dynamically cross‐linking phenylboronic acid‐functionalized poly(methylmethacrylate) (PMMA‐B) poly(urea‐urethane) (PUU‐B) with boroxines. plastic, which is denoted PMMA‐PUU exhibits breaking strength 71.0 MPa Young's modulus 1.8 GPa. Because dynamic nature boroxines, 0.6 plastic can be depolymerized N, N‐dimethylacetamide/ethanol mixture solvent. PMMA PUU recovered high yields purity through their solubility differences selective solvents. Conductive suitable printing electrical circuits complexation Ag particles PMMA‐PUU. composed PMMA‐PUU‐based flexible, healable, recyclable. enables collection purified particles, PMMA‐B, PUU‐B monomers even when mixed wastes.

Язык: Английский

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Acetal‐thiol Click‐like Reaction: Facile and Efficient Synthesis of Dynamic Dithioacetals and Recyclable Polydithioacetals

Angewandte Chemie International Edition, Год журнала: 2024, Номер 63(31)

Опубликована: Май 20, 2024

Dithioacetals are heavily used in organic, material and medical chemistries, exhibit huge potential to synthesize degradable or recyclable polymers. However, the current synthetic approaches of dithioacetals polydithioacetals overwhelmingly dependent on external catalysts organic solvents. Herein, we disclose a catalyst- solvent-free acetal-thiol click-like reaction for synthesizing polydithioacetals. High conversion, higher than acid catalytic reaction, can be achieved. universality was confirmed by monitoring reactions linear cyclic acetals (including renewable bio-sourced furan-acetal) with aliphatic aromatic thiols, mechanism monomolecular nucleophilic substitution (S

Язык: Английский

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Dynamic covalent adhesives and their applications: Current progress and future perspectives

Chemical Engineering Journal, Год журнала: 2024, Номер 497, С. 154710 - 154710

Опубликована: Авг. 13, 2024

Язык: Английский

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Structure–Property Relationships of Elastomeric Vinylogous Urethane Thermosets and Their Application as Closed-Loop Recyclable Strain Sensors

Macromolecules, Год журнала: 2025, Номер 58(4), С. 1923 - 1934

Опубликована: Фев. 5, 2025

Developing closed-loop recyclable thermosets and understanding their structure–property relationships are essential steps in advancing a circular materials economy. Here, we present vinylogous urethane (VU) thermoset with recyclability, synthesized through the reaction of polytetrahydrofuran bisacetoacetate (aPTHF) tris(2-aminoethyl)amine (TREN). These VU polymers exhibit high elasticity, only 3–9% residual strain observed after cyclic tensile testing at maximum 100%, depending on molecular weight aPTHF network cross-link density. The two structural parameters also allow modulation mechanical stress-relaxation properties elastomers. To investigate hydrolysis linkages within hydrophobic matrix, employed heterogeneous system using biphasic mixture HCl CDCl3. Our findings show that VUs remain stable pure water but can be dissociated under acidic conditions, dissociation rate accelerated higher temperatures and/or presence concentrations. detailed investigations indicate potential elastomers as sustainable substrates for wearable sensors. We therefore conduct case study synthesizing sensor incorporation multiwalled carbon nanotubes (MCNs) into elastomer matrix. robustly detect various movements. Moreover, treatment both neat polymer composite diethyl ether solvent allows excellent recovery (>90%) TREN (86%), without discernible damage to MCNs reclaimed from latter.

Язык: Английский

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