Dynamic Covalent Polymer Networks: A Molecular Platform for Designing Functions beyond Chemical Recycling and Self-Healing

Chemical Reviews, Journal Year: 2021, Volume and Issue: 121(3), P. 1716 - 1745

Published: Jan. 4, 2021

Dynamic covalent polymer networks (DCPN) have historically attracted attention for their unique roles in chemical recycling and self-healing, which are both relevant sustainable societal development. Efforts these directions intensified the past decade with notable progress newly discovered dynamic chemistry, fundamental material concepts, extension toward emerging applications including energy electronic devices. Beyond that, values of DCPN discovering/designing functional properties not offered by classical thermoplastic thermoset polymers recently gained traction. In particular, bond exchangeability has shown unparalleled design versatility various areas shape-shifting materials/devices, artificial muscles, microfabrication. Going beyond this basic exchangeability, molecular mechanisms to manipulate network topologies (topological transformation) led opportunities program polymers, concepts such as living topological isomerization. review, we provide an overview above particular focuses on strategies exploitation properties. Based this, point out remaining issues offer perspectives how class materials can shape future ways that complementary polymers.

Language: Английский

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Healable and Recyclable Elastomers with Record‐High Mechanical Robustness, Unprecedented Crack Tolerance, and Superhigh Elastic Restorability

Advanced Materials, Journal Year: 2021, Volume and Issue: 33(27)

Published: June 1, 2021

Abstract Spider silk is one of the most robust natural materials, which has extremely high strength in combination with great toughness and good elasticity. Inspired by spider but beyond it, a healable recyclable supramolecular elastomer, possessing superhigh true stress at break (1.21 GPa) ultrahigh (390.2 MJ m −3 ), are, respectively, comparable to ≈2.4 times higher than those typical silk, developed. The elastomer highest tensile (ultimate engineering stress, 75.6 MPa) ever recorded for polymeric elastomers, rendering it strongest toughest thus far. hyper‐robust exhibits superb crack tolerance unprecedentedly fracture energy (215.2 kJ −2 ) that even exceeds metals alloys, elastic restorability allowing dimensional recovery from elongation over 12 times. These extraordinary mechanical performances mainly originate meticulously engineered hydrogen‐bonding segments, consisting multiple acylsemicarbazide urethane moieties linked flexible alicyclic hexatomic spacers. Such incorporated between extensible polymer chains, aggregate form geometrically confined hydrogen‐bond arrays resembling silk. act as firm reversible crosslinks sacrificial bonds enormous dissipation, conferring exceptional robustness, healability, recyclability on elastomer.

Language: Английский

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Intrinsically Self-Healing Polymers: From Mechanistic Insight to Current Challenges

Chemical Reviews, Journal Year: 2022, Volume and Issue: 123(2), P. 701 - 735

Published: Dec. 28, 2022

Self-healing materials open new prospects for more sustainable technologies with improved material performance and devices' longevity. We present an overview of the recent developments in field intrinsically self-healing polymers, broad class based mostly on polymers dynamic covalent noncovalent bonds. describe current models mechanisms discuss several examples systems different types bonds, from various hydrogen bonds to The advances indicate that most intriguing results are obtained have combined These demonstrate high toughness along a relatively fast rate. There is clear trade-off relationship between rate mechanical modulus materials, we propose design principles toward surpassing this trade-off. also applications summarize challenges field. This review intends provide guidance intrinsic required properties.

Language: Английский

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Extremely Strong and Tough Biodegradable Poly(urethane) Elastomers with Unprecedented Crack Tolerance via Hierarchical Hydrogen‐Bonding Interactions

Advanced Materials, Journal Year: 2023, Volume and Issue: 35(21)

Published: Feb. 23, 2023

The elastomers with the combination of high strength and toughness have always been intensively pursued due to their diverse applications. Biomedical applications frequently require biodegradability biocompatibility properties. It remains a great challenge prepare biodegradable extremely robust mechanical properties for in vivo use. In this report, we present polyurethane elastomer unprecedented application as hernia patches, which was obtained by solvent-free reaction polycaprolactone (PCL) isophorone diisocyanate (IPDI) N,N-bis(2-hydroxyethyl)oxamide (BHO) chain extender. Abundant hierarchical hydrogen-bonding interactions inside hinder crystallization PCL segments facilitate formation uniformly distributed hard phase microdomains, miraculously realize fracture 92.2 MPa true stress 1.9 GPa, while maintaining elongation-at-break ≈1900% ultrahigh 480.2 MJ m-3 energy 322.2 kJ m-2 . Hernia patches made from via 3D printing technology exhibit outstanding properties, biocompatibility, biodegradability. demonstrate considerable potentials

Language: Английский

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Fatigue-free artificial ionic skin toughened by self-healable elastic nanomesh

Nature Communications, Journal Year: 2022, Volume and Issue: 13(1)

Published: July 29, 2022

Abstract Robust ionic sensing materials that are both fatigue-resistant and self-healable like human skin essential for soft electronics robotics with extended service life. However, most existing artificial skins produced on the basis of network reconfiguration suffer from a low fatigue threshold due to easy fracture low-energy amorphous polymer chains susceptible crack propagation. Here we engineer fatigue-free yet fully healable hybrid toughened by high-energy, elastic nanomesh, resembling repairable nanofibrous interwoven structure skin. Such design affords superhigh 2950 J m −2 while maintaining skin-like compliance, stretchability, strain-adaptive stiffening response. Moreover, nanofiber tension-induced moisture breathing matrix leads record-high strain-sensing gauge factor 66.8, far exceeding previous intrinsically stretchable conductors. This concept creates opportunities designing durable ion-conducting replicate unparalleled combinatory properties natural more precisely.

Language: Английский

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Molecular engineering of a colorless, extremely tough, superiorly self-recoverable, and healable poly(urethane–urea) elastomer for impact-resistant applications

Materials Horizons, Journal Year: 2021, Volume and Issue: 8(8), P. 2238 - 2250

Published: Jan. 1, 2021

Molecular engineering of a microphase separated structure to convert weak, soft and self-healing polymer strong, tough, resilient, healable poly(urethane–urea) elastomer, which is in great demand for transparent protection engineering.

Language: Английский

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Thermally conductive, self-healing, and elastic Polyimide@Vertically aligned carbon nanotubes composite as smart thermal interface material

Carbon, Journal Year: 2021, Volume and Issue: 179, P. 348 - 357

Published: April 20, 2021

Language: Английский

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Self-healing polyurethane with high strength and toughness based on a dynamic chemical strategy

Journal of Materials Chemistry A, Journal Year: 2022, Volume and Issue: 10(18), P. 10139 - 10149

Published: Jan. 1, 2022

Menthane diamine promotes the strength and toughness of H-bonding disulfide bonding-based self-healing polyurethane elastomers simultaneously improves elasticity performance.

Language: Английский

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Fully recyclable multifunctional adhesive with high durability, transparency, flame retardancy, and harsh-environment resistance

Science Advances, Journal Year: 2022, Volume and Issue: 8(50)

Published: Dec. 14, 2022

Recyclable/reversible adhesives have attracted growing attention for sustainability and intelligence but suffer from low adhesion strength poor durability in complex conditions. Here, we demonstrate an aromatic siloxane adhesive that exploits stimuli-responsive reversible assembly driven by π-π stacking, allowing elimination activation of interfacial interactions via infiltration-volatilization ethanol. The robust cohesive energy water-insensitive enables durable strong (3.5 MPa shear on glasses) diverse surfaces. Long-term performances are realized underwater, salt, acid/alkali solutions (pH 1-14) at low/high temperatures (-10-90°C). With assembly/disassembly, the is closed-loop recycled (~100%) reused over 100 times without loss. Furthermore, has unique combinations high transparency (~98% visible light region 400-800 nm) flame retardancy. experiments theoretical calculations reveal corresponding mechanism molecular level. This stacking-driven strategy opens up avenue high-performance with circular life multifunctional integration.

Language: Английский

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Engineering of Chain Rigidity and Hydrogen Bond Cross‐Linking toward Ultra‐Strong, Healable, Recyclable, and Water‐Resistant Elastomers

Advanced Materials, Journal Year: 2023, Volume and Issue: 35(21)

Published: Feb. 28, 2023

High-performance elastomers have gained significant interest because of their wide applications in industry and our daily life. However, it remains a great challenge to fabricate simultaneously integrating ultra-high mechanical strength, toughness, excellent healing recycling capacities. In this study, ultra-strong, healable, recyclable are fabricated by dynamically cross-linking copolymers composed rigid polyimide (PI) segments soft poly(urea-urethane) (PUU) with hydrogen bonds. The elastomers, which denoted as PIPUU, record-high tensile strength ≈142 MPa an extremely high toughness ≈527 MJ m-3 . structure the PIPUU elastomer contains hydrogen-bond-cross-linked elastic matrix homogenously dispersed nanostructures. PI self-assemble generate phase-separated nanostructures that serve nanofillers significantly strengthen elastomers. Meanwhile, is PUU cross-linked reversible bonds, largely enhance elastomer. can be healed recycled restore original strength. Moreover, performance hydrophobic segments, scratch-, puncture-, water-resistant.

Language: Английский

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