Mechanochromic, Shape‐Programmable and Self‐Healable Cholesteric Liquid Crystal Elastomers Enabled by Dynamic Covalent Boronic Ester Bonds

Angewandte Chemie International Edition, Год журнала: 2021, Номер 61(9)

Опубликована: Дек. 28, 2021

Endowing a cholesteric liquid crystal elastomer (CLCE) exhibiting helicoidal nanostructure with dynamically tailorable functionalities is of paramount significance for its emerging applications in diverse fields such as adaptive optics and soft robotics. Here, mechanochromic, shape-programmable self-healable CLCE judiciously designed synthesized through integrating dynamic covalent boronic ester bonds into the main-chain polymer network. The circularly polarized reflection CLCEs can be reversibly tuned across entire visible spectrum by mechanical stretching. Thanks to introduction bonds, were found show robust reprogrammable self-healing capabilities. research disclosed herein provide new insights development 4D (color 3D shape) programmable photonic actuators towards bioinspired camouflage, optical systems, next-generation intelligent machines.

Язык: Английский

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

Advanced Materials, Год журнала: 2023, Номер 35(21)

Опубликована: Фев. 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

Язык: 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, Год журнала: 2021, Номер 8(8), С. 2238 - 2250

Опубликована: Янв. 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.

Язык: Английский

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Room-temperature self-healing supramolecular polyurethanes based on the synergistic strengthening of biomimetic hierarchical hydrogen-bonding interactions and coordination bonds

Chemical Engineering Journal, Год журнала: 2022, Номер 451, С. 138673 - 138673

Опубликована: Авг. 18, 2022

Язык: Английский

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

Journal of Materials Chemistry A, Год журнала: 2022, Номер 10(18), С. 10139 - 10149

Опубликована: Янв. 1, 2022

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

Язык: Английский

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Multiple Structure Reconstruction by Dual Dynamic Crosslinking Strategy Inducing Self‐Reinforcing and Toughening the Polyurethane/Nanocellulose Elastomers

Advanced Functional Materials, Год журнала: 2023, Номер 33(12)

Опубликована: Янв. 15, 2023

Abstract High‐performance elastomers are expected to possess excellent healing and recycling ability, damage resistance in conjunction with high strength toughness. Herein, a dual dynamic crosslinking strategy is implemented by multiple hydrogen disulfide bonds obtain novel amorphous transparent polyurethane/nanocellulose elastomer self‐healing, self‐reinforcing toughening performance. First, introduced TEMPO‐oxidized cellulose nanofibers (TCNF) modification 2‐ureido‐4[1H]‐pyrimidone (UTCNF), while (SS) the polyurethane (PU) main chain, leading formation of cross‐linking networks. The PU‐SS‐UTCNF can fully self‐heal within 4.0 h at 50 °C. Surprisingly, for first time, also self‐strengthens self‐toughens after hot‐pressing, tensile toughness that increase up 401% 257% compared original samples, 50.0 MPa 132.5 MJ m ‐3 . self‐strength self‐toughening effects attributed 1) reconstruction networks degree during hot‐pressing processes; 2) system beneficial orientation highly crystallized UTCNF, as replacement stress‐induced process deformation under external force.

Язык: Английский

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An unparalleled H-bonding and ion-bonding crosslinked waterborne polyurethane with super toughness and unprecedented fracture energy

Materials Horizons, Год журнала: 2021, Номер 8(10), С. 2742 - 2749

Опубликована: Янв. 1, 2021

A H-bonding and ion-bonding crosslinked waterborne polyurethane exhibits an ultrahigh tensile strength, super toughness, record fracture energy. Dynamic reconstruction of H-bonds ionic bonds enables self-healability 3D reprocessability.

Язык: Английский

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Self-Healable, Solvent Response Cellulose Nanocrystal/Waterborne Polyurethane Nanocomposites with Encryption Capability

ACS Nano, Год журнала: 2023, Номер 17(6), С. 5653 - 5662

Опубликована: Март 10, 2023

Cellulose nanocrystal (CNC)-based chiral nematic structure is widely used in stimulus response and sensing. A popular area of research enhancing the mechanical characteristics environmental adaptability materials. In this paper, a flexible photonic film with self-healing ability (FPFS) was prepared by combining waterborne polyurethane containing dynamic covalent disulfide bonds (SSWPU) CNC. The results found that FPFS showed excellent toughness under action stretching, bending, twisting, folding. exhibited an amazing efficiency, which can be self-healed within 2 h at room temperature. Moreover, could respond immediately produce reversible color change when it soaked typical solvents. addition, ethanol as ink to paint on FPFS, visible pattern only polarized light formed. This study offers fresh perspectives areas self-healing, biological anticounterfeiting, solvent response,

Язык: Английский

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A stretchable, mechanically robust polymer exhibiting shape-memory-assisted self-healing and clustering-triggered emission

Nature Communications, Год журнала: 2023, Номер 14(1)

Опубликована: Авг. 5, 2023

Abstract Self-healing and recyclable polymer materials are being developed through extensive investigations on noncovalent bond interactions. However, they typically exhibit inferior mechanical properties. Therefore, the present study is aimed at synthesizing a polyurethane–urea elastomer with excellent properties shape-memory-assisted self-healing behavior. In particular, introduction of coordination hydrogen bonds into leads to optimal exhibiting good (strength, 76.37 MPa; elongation break, 839.10%; toughness, 308.63 MJ m −3 ) owing phased energy dissipation mechanism involving various supramolecular The also demonstrates shape-memory properties, whereby shape recovery force that brings damaged surfaces closer facilitates self-healing. Surprisingly, all specimens exhibite clustering-triggered emission, cyan fluorescence observed under ultraviolet light. strategy reported herein for developing multifunctional can be leveraged yield stimulus-responsive polymers smart seals.

Язык: Английский

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Development of Tough Thermoplastic Elastomers by Leveraging Rigid–Flexible Supramolecular Segment Interplays

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

Опубликована: Май 20, 2023

Supramolecular interactions facilitate the development of tough multifunctional thermoplastic elastomers. However, fundamental principles that govern supramolecular toughening are barely understood, and rational design to achieve desired high toughness remains daunting. Herein, we report a simple robust method for elastomers by rationally tailoring hard-soft phase separation structures containing rigid flexible segments. The introduced functional segments with distinct structural rigidities provide mismatched efficiently tune energy dissipation bear an external load. optimal elastomer aromatic amide acylsemicarbazide moieties demonstrates record (1.2 GJ m-3 ), extraordinary crack tolerance (fracture 282.5 kJ m-2 ultrahigh true stress at break (2.3 GPa), good elasticity, healing ability, recyclability, impact resistance. mechanism is validated testing various elastomers, confirming potential designing developing super-tough materials promising applications in aerospace electronics.

Язык: Английский

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