Intrinsic Anti‐Freezing, Tough, and Transparent Hydrogels for Smart Optical and Multi‐Modal Sensing Applications

Advanced Materials, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 8, 2025

Abstract Hydrogels have received great attention due to their molecular designability and wide application range. However, they are prone freeze at low temperatures the existence of mass water molecules, which can damage flexibility transparency, greatly limiting use in cold environments. Although adding cryoprotectants reduce freezing point hydrogels, it may also deteriorate mechanical properties face risk cryoprotectant leakage. Herein, microphase‐separated structures hydrogels regulated confine molecules sub‐6 nm nanochannels increase proportion bound water, endowing with intrinsic anti‐freezing properties, high strength, good stretchability, remarkable fracture energy, puncture resistance. Even after being kept liquid nitrogen for 1000 h, hydrogel still maintains transparency. The exhibit excellent low‐temperature shape memory intelligent optical waveguide properties. Additionally, be assembled into strain pressure sensors flexible sensing both room temperatures. intrinsically offers broad prospects electronic applications.

Language: Английский

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Conductive hydrogels with HPC additions for humidity sensing and temperature response

Chemical Engineering Journal, Journal Year: 2025, Volume and Issue: unknown, P. 160000 - 160000

Published: Jan. 1, 2025

Language: Английский

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Mechanical Regulation of Polymer Gels

Chemical Reviews, Journal Year: 2024, Volume and Issue: 124(18), P. 10435 - 10508

Published: Sept. 16, 2024

The mechanical properties of polymer gels devote to emerging devices and machines in fields such as biomedical engineering, flexible bioelectronics, biomimetic actuators, energy harvesters. Coupling network architectures interactions has been explored regulate supportive characteristics gels; however, systematic reviews correlating mechanics interaction forces at the molecular structural levels remain absent field. This review highlights engineering gel a comprehensive mechanistic understanding regulation. Molecular alters architecture manipulates functional groups/moieties level, introducing various permanent or reversible dynamic bonds dissipative energy. usually uses monomers, cross-linkers, chains, other additives. Structural utilizes casting methods, solvent phase regulation, mechanochemistry, macromolecule chemical reactions, biomanufacturing technology construct tailor topological structures, heterogeneous modulus compositions. We envision that perfect combination may provide fresh view extend exciting new perspectives this burgeoning also summarizes recent representative applications with excellent properties. Conclusions are provided from five aspects concise summary, mechanism, biofabrication upgraded applications, synergistic methodology.

Language: Английский

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Self‐Polymerized Tough and High‐Entanglement Zwitterionic Functional Hydrogels

Small, Journal Year: 2024, Volume and Issue: unknown

Published: Sept. 25, 2024

Abstract Zwitterionic hydrogels exhibit great potential in biomedical applications due to their antifouling properties and biocompatibility. However, the single‐network structure of pure zwitterionic leads a low toughness strength, limiting application fields. In this work, high entanglement sulfobetaine methacrylate‐dopamine hydrogel (SBMA‐DA‐PE) with cross‐linker content monomer concentration is prepared by using dopamine oxidative radical polymerization method. Compared regular hydrogel, SBMA‐DA‐PE exhibits 5‐fold increase tensile fracture stress 10‐fold compressive stress. The possesses excellent mechanical (the maximum ≥4.85 MPa, strain ≥90%). Besides, non‐covalent interactions between catechol or ortho‐quinones within combined strong intermolecular electrostatic interactions, endow self‐healing capabilities fatigue resistance. demonstrates swellability good properties. Furthermore, printability conductivity tough endows it new possibilities for developing biological 3D scaffolds electronic devices. Overall, work provides insights into preparation strength multi‐functionality applications.

Language: Английский

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Robust and Lubricating Interface Semi‐Interpenetrating Network on Inert Polymer Substrates Enabled by Subsurface‐Initiated Polymerization

Small, Journal Year: 2024, Volume and Issue: 20(43)

Published: June 20, 2024

Abstract Lubricating hydrogel coatings on inert rubber and plastic surfaces significantly reduce friction wear, thus enhancing material durability lifespan. However, achieving optimal hydration lubrication typically requires a porous polymer network, which unfortunately reduces their mechanical strength limits applicability where robust wear‐resistance are essential. In the research, coating with remarkable wear resistance surface stability is developed by forming semi‐interpenetrating network substrate at interface. By employing good solvent swelling method, monomers, photoinitiators embedded within substrates' subsurface, followed in situ polymerization under ultraviolet light, creating entangled structure. This approach, offering thicker energy‐dissipating layer, outperforms traditional modifications while preserving anti‐fatigue, hydrophilicity, oleophobicity, other properties. Adaptable to various substrates using suitable solvents, this method provides an efficient solution for durable, lubricating surfaces, broadening potential applications multiple industries.

Language: Английский

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Fracture Behavior and Biocompatibility of Cellulose Nanofiber-Reinforced Poly(vinyl alcohol) Composite Hydrogels Cross-Linked with Borax

Biomacromolecules, Journal Year: 2024, Volume and Issue: 26(1), P. 374 - 386

Published: Dec. 9, 2024

We investigated the fracture behavior of cellulose nanofiber (CNF)-reinforced poly(vinyl alcohol) (PVA) hydrogels cross-linked with borax and effect freeze-thaw (FT) cycles on it. The CNF/PVA/Borax hydrogel not subjected to FT achieved a energy 5.8 kJ m-2 dissipative length 2.3 mm, comparable those tough hydrogels. Lacking either CNF or remarkably decreased length; contributed physical blocking crack growth, whereas complexations between borate yielded nonlocalization dissipation. Repeated markedly improved mechanical performance unnotched samples, but they due lowering length. Besides, were suitable for cell scaffold materials. culture umbilical cord mesenchymal stem cells (UC-MSCs) revealed positive correlation duration number UC- MSCs adherent material.

Language: Английский

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An Organic–Inorganic Hydrogel with Exceptional Mechanical Properties via Anion‐Induced Synergistic Toughening for Accelerating Osteogenic Differentiation

Small, Journal Year: 2024, Volume and Issue: 20(43)

Published: June 19, 2024

Abstract Mineralized bio‐tissues achieve exceptional mechanical properties through the assembly of rigid inorganic minerals and soft organic matrices, providing abundant inspiration for synthetic materials. Hydrogels, serving as an ideal candidate to mimic matrix in bio‐tissues, can be strengthened by direct introduction minerals. However, this enhancement often comes at expense toughness due interfacial mismatch. This study reveals that extreme toughening hydrogels realized simultaneous situ mineralization salting‐out, without need special chemical modification or additional reinforcements. The key strategy lies harnessing kosmotropic precipitation behavior specific anions they penetrate a hydrogel system containing both anion‐sensitive polymers multivalent cations. resulting mineralized demonstrate significant improvements fracture stress, energy, fatigue threshold multiscale energy dissipation mechanism, with optimal values reaching 12 MPa, 49 kJ m −2 , 2.98 . simple also proves generalizable other anions, tough osteoconductivity promoting vitro human adipose‐derived mesenchymal stem cells. work introduces universal route toughen compromising parameters, holding promise biological applications demanding integrated properties.

Language: Английский

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Fatigue‐Resistant Mechanoresponsive Color‐Changing Hydrogels for Vision‐Based Tactile Robots

Advanced Materials, Journal Year: 2024, Volume and Issue: unknown

Published: Sept. 27, 2024

Abstract Mechanoresponsive color‐changing materials that can reversibly and resiliently change color in response to mechanical deformation are highly desirable for diverse modern technologies optics, sensors, robots; however, such rarely achieved. Here, a fatigue‐resistant mechanoresponsive hydrogel (FMCH) is reported exhibits reversible, resilient, predictable changes under stress. At its undeformed state, the FMCH remains dark circular polariscope; upon uniaxial stretching of up six times initial length, it gradually shifts from black, gray, yellow, purple. Unlike traditional materials, maintains performance across various strain rates 10 000 cycles. Moreover, demonstrates superior properties with fracture toughness 3000 J m −2 , stretchability 6, fatigue threshold 400 . These exceptional optical features attributed FMCH's substantial molecular entanglements hygroscopic salts, which synergistically enhance while preserving performance. One application this as tactile sensoris then demonstrated vision‐based robots, enabling them discern material stiffness, object shape, spatial location, applied pressure by translating stress distribution on contact surface into discernible images.

Language: Английский

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Extreme Toughening of Conductive Hydrogels Through Synergistic Effects of Mineralization, Salting‐Out, and Ion Coordination Induced by Multivalent Anions

Small, Journal Year: 2024, Volume and Issue: unknown

Published: Nov. 22, 2024

Abstract Developing conductive hydrogels with both high strength and fracture toughness for diverse applications remains a significant challenge. In this work, an efficient toughening strategy is presented that exploits the multiple enhancement effects of anions through synergistic combination mineralization, salting‐out, ion coordination. The approach centers on hydrogel system comprising two polymers cation highly responsive to anions. Specifically, polyvinyl alcohol (PVA) chitosan quaternary ammonium (HACC) are used, as PVA benefits from salting‐out HACC undergoes coordination multivalent After just 1 h immersion in anionic solution, dramatic improvement mechanical properties, increasing by more than three orders magnitude. optimized achieves (26 MPa), Young's modulus (45 remarkable (67.3 kJ m −2 ), representing enhancements 860, 3200, 1200 times, respectively, compared its initial state. This breakthrough overcomes typical trade‐off between stiffness toughness. Additionally, ionic conductivity enables reliable strain sensing supports development durable supercapacitors. work presents simple effective pathway developing exceptional strength, toughness, conductivity.

Language: Английский

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Crystalline‐Constrain Enables Preparation of Hierarchical Porous Hydrogels with High Porosity and Good Mechanics

Advanced Functional Materials, Journal Year: 2024, Volume and Issue: unknown

Published: Dec. 13, 2024

Abstract Porous hydrogels with high porosity can achieve matter diffusion and transport efficiency. Achieving both ultrahigh excellent mechanical properties in porous remains a long‐standing challenge, considerably hindering their use load‐bearing elastic scaffolds such as artificial articular cartilages meniscus replacements. Herein, novel crystalline‐constrained multi‐solvents template preparation method is proposed for synthesizing highly hierarchical polyvinyl alcohol (P‐exogel) properties. The enhanced characteristics of the P‐exogel are attributed to crystallinity‐induced network anti‐swelling effect pore walls during dynamic removal. exhibits interconnected structure (81.69%), resulting ultrafast surface wetting water (in less than 10 ms). Moreover, good tensile breaking strength (2.47 ± 0.53 MPa) elongation more 400%, toughness (5.61 1.65 MJ m −3 ), recovery performance. pre‐crack testing results further confirm fracture resistance (18.73 2.52 KJ −2 ) P‐exogel, which almost surpasses those all reported commercial hydrogels. unique microstructure ensures its efficient reversible liquid absorption release ability loading–unloading processes, confirming great application potential scaffolds.

Language: Английский

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