Knoevenagel C═C Metathesis Enabled Glassy Vitrimers with High Rigidity, Toughness, and Malleability

Journal of the American Chemical Society, Год журнала: 2024, Номер 146(23), С. 16112 - 16118

Опубликована: Май 28, 2024

Thermosets, characterized by their permanent cross-linked networks, present significant challenges in recyclability and brittleness. In this work, we explore a polarized Knoevenagel C═C metathesis reaction for the development of rigid yet tough malleable thermosets. Initial investigation on small molecule model reactions reveals feasibility conducting base-catalyzed solvent-free environment. Subsequently, thermosetting poly(α-cyanocinnamate)s (PCCs) were synthesized via condensation between triarm cyanoacetate star dialdehyde. The thermal mechanical properties developed PCCs can be easily modulated altering structure Remarkably, introduction ether groups into PCC leads to combination high rigidity toughness with Young's modulus ∼1590 MPa, an elongation at break ∼79%, reaching ∼30 MJ m3. These values are competitive traditional thermosets, but far exceed them ductility toughness. Moreover, facilitates stress relaxation within bulk polymer thus rendering excellent malleability reprocessability. This work overcomes limitations introducing groundbreaking insights design contributing significantly sustainability materials.

Язык: Английский

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Dynamic Covalent Bonds Enabled Carbon Fiber Reinforced Polymers Recyclability and Material Circularity

Angewandte Chemie International Edition, Год журнала: 2024, Номер unknown

Опубликована: Июль 20, 2024

Due to their remarkable features of lightweight, high strength, stiffness, high-temperature resistance, and corrosion carbon fiber reinforced polymers (CFRPs) are extensively used in sports equipment, vehicles, aircraft, windmill blades, other sectors. The urging need develop a resource-saving environmentally responsible society requires the recycling CFRPs. Traditional CFRPs, on hand, difficult recycle due permanent covalent crosslinking polymer matrices. combination adaptable networks (CANs) with fibers (CFs) marks new development path for closed-loop recyclable CFRPs resins. In this review, we summarize most recent developments from unique paradigm dynamic polymers, CANs. These sophisticated materials diverse functions, oriented towards CFs resin sustainability, further categorized into several active domains bonds, including ester imine disulfide boronic acetal linkages, etc. Finally, possible strategies future design CFPRs by combining chemistry innovation interface science proposed.

Язык: Английский

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Soft‐Rigid Construction of Mechanically Robust, Thermally Stable, and Self‐Healing Polyimine Networks with Strongly Recyclable Adhesion

Small, Год журнала: 2024, Номер unknown

Опубликована: Окт. 11, 2024

Abstract Reversible and recyclable thermosets have garnered increasing attention for their smart functionality sustainability. However, they still face challenges in balancing comprehensive performance dynamic features. Herein, silicon (Si)─oxygen (O) imidazole units covalent bonds are coupled to generate a new class of bio‐polyimines (Bio‐Si‐PABZs), endow them with high excellent reprocessing capability acid‐degradability. By tailoring the molar content diamines, this Bio‐Si‐PABZs displayed both markedly glass transition temperature (162 °C) char yield at 800 °C an oxygen atmosphere (73.1%). These favorable properties outperformed various previously reported polyimines competed effectively commercial fossil‐based polycarbonate. Moreover, scratch (≈10 µ m) on surface samples can be self‐healing within only 2 min, effective “ Bird Nest ”‐to‐“ Torch ” recycling also achieved through free amines solution. Most importantly, bio‐based siloxane adhesive derived from intermediate Bio‐Si‐PABZ‐1 by acidic degradation demonstrated broad robust adhesion substrates, values reaching up ≈3.5 MPa. For first time, study lays scientific groundwork designing polyimine Si─O units, as well converting plastic wastes into thermal‐reversibility renewable adhesives.

Язык: Английский

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Foam‐to‐Foam Recycling Potential of PU‐Foams by Integration of Amino Esters

Advanced Functional Materials, Год журнала: 2024, Номер unknown

Опубликована: Сен. 27, 2024

Abstract The increasing market demand for flexible polyurethane foams (PUFs) is prompting the academic and industrial community to seek solutions their end‐of‐life management. In this study, issue addressed by incorporating β‐amino ester (BAE) moieties into foam structure. This addition results in hybrid PU‐BAE that can be thermally reprocessed chemically recycled, with cell sizes ranging from 780 990 µm densities between 90 150 kg m −3 . These demonstrate thermomechanical reprocessability, yielding stable elastomers, glass transition temperature values 14 25 °C. Stress relaxation experiments reveal remarkably fast times these elastomers (23 s at 160 °C). Furthermore, a systematic investigation of chemical recyclability via glycosylation conducted under mild conditions, achieving complete disintegration within 20 min 65 Finally, recycled product converted again, closed loop foam‐to‐foam recycling process. findings indicate integration BAE PUFs leads an enhanced rate, providing promising avenue addressing concerns PUF‐applications.

Язык: Английский

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Dynamic Covalent Bonds Enabled Carbon Fiber Reinforced Polymers Recyclability and Material Circularity

Angewandte Chemie, Год журнала: 2024, Номер 136(40)

Опубликована: Июль 20, 2024

Abstract Due to their remarkable features of lightweight, high strength, stiffness, high‐temperature resistance, and corrosion carbon fiber reinforced polymers (CFRPs) are extensively used in sports equipment, vehicles, aircraft, windmill blades, other sectors. The urging need develop a resource‐saving environmentally responsible society requires the recycling CFRPs. Traditional CFRPs, on hand, difficult recycle due permanent covalent crosslinking polymer matrices. combination adaptable networks (CANs) with fibers (CFs) marks new development path for closed‐loop recyclable CFRPs resins. In this review, we summarize most recent developments from unique paradigm dynamic polymers, CANs. These sophisticated materials diverse functions, oriented towards CFs resin sustainability, further categorized into several active domains bonds, including ester imine disulfide boronic acetal linkages, etc. Finally, possible strategies future design CFPRs by combining chemistry innovation interface science proposed.

Язык: Английский

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Ligand Dissociation of Metal-Complex Photocatalysts toward pH-Photomanipulation in Dynamic Covalent Hydrogels for Printing Reprocessable and Recyclable Devices

ACS Macro Letters, Год журнала: 2024, Номер 13(6), С. 664 - 672

Опубликована: Май 16, 2024

Dynamic covalent hydrogels are gaining attention for their potential in smart materials, soft devices, electronics, and more thanks to impressive mechanical properties, biomimetic structures, dynamic behavior. However, a significant challenge lies designing precise efficient photochemistry preparation, allowing complex structures control over the process. Herein, we propose general straightforward orthogonal strategy preparing high-performance printable hydrogels, thereby broadening advanced applications. This photochemical uses bifunctional photocatalyst initiate radical polymerization release ligands through rapid light-mediated dissociation mechanism. process leads controlled increase system pH from mildly acidic alkaline conditions within one hundred seconds, which turn triggers pH-sensitive model reactions of boronic acid/diol complexation Knoevenagel condensation. The enables formation interpenetrated conjoined networks, significantly enhancing properties hydrogels. reversible bonds formed during process, i.e., ester unsaturated ketone bonds, confer excellent self-healing, reprocessable, recyclable on variations. Furthermore, this rapid, fabrication behavior highly compatible with printing techniques, enabling design adaptive sensors different structures. These advancements promising various material science, medicine, engineering

Язык: Английский

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Colours and microplastics: Bridging the gap between art, science and sustainability

Sustainable materials and technologies, Год журнала: 2024, Номер unknown, С. e01152 - e01152

Опубликована: Окт. 1, 2024

Язык: Английский

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Low Dielectric and High Thermal Conductivity Polyimide Nanocomposites with Fully Closed-Loop Recycling and Highly Consistent Healing

Composites Part B Engineering, Год журнала: 2025, Номер unknown, С. 112390 - 112390

Опубликована: Март 1, 2025

Язык: Английский

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Red Sea Star-Inspired, Rapid Underwater Self-Healing Polyurethane Based on Dual Hydrophobic Units and Tandem Dynamic Bonds

Macromolecules, Год журнала: 2025, Номер unknown

Опубликована: Апрель 25, 2025

Язык: Английский

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Internally Catalyzed Polarized C═C Vitrimers

Macromolecules, Год журнала: 2025, Номер unknown

Опубликована: Май 7, 2025

Язык: Английский

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