Toughening Double‐Network Hydrogels by Polyelectrolytes

Advanced Materials, Journal Year: 2023, Volume and Issue: 35(26)

Published: March 20, 2023

The Hoffmeister effect of inorganic salts is verified as a promising way to toughen hydrogels, however, the high concentration may be accompanied by poor biocompatibility. In this work, it found that polyelectrolytes can obviously elevate mechanical performances hydrogels through effect. introduction anionic poly(sodium acrylate) into poly(vinyl alcohol) (PVA) hydrogel induces aggregation and crystallization PVA boost properties resulting double-network hydrogel: elevation 73, 64, 28, 135, 19 times in tensile strength, compressive Young's modulus, toughness, fracture energy compared with poly(acrylic acid), respectively. It noteworthy flexibly tuned variation polyelectrolyte concentration, ionization degree, relative hydrophobicity ionic component, type wide range. This strategy work for other Hoffmeister-effect-sensitive polymers polyelectrolytes. Also, urea bonds further improve antiswelling capability hydrogels. As biomedical patch, advanced efficiently inhibit hernia formation promote regeneration soft tissues an abdominal wall defect model.

Language: Английский

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Strong and Tough Physical Eutectogels Regulated by the Spatiotemporal Expression of Non‐Covalent Interactions

Advanced Functional Materials, Journal Year: 2022, Volume and Issue: 32(41)

Published: Aug. 5, 2022

Abstract Physical eutectogels are appealing materials for technological devices due to their superior ionic conductivity, thermal and electrochemical stability, non‐volatility, low cost. Nevertheless, current physical suffering from weak mechanical strength toughness. Here, taking advantage of the distribution difference polyvinyl alcohol (PVA) in water deep eutectic solvents (DESs), a simple universal solvent‐replacement approach is proposed regulate spatiotemporal expression intra/interpolymer interactions prepare strong tough eutectogels. The exchange DESs with can restrengthen weakened between PVA chains water, enabling crystallize construct uniform robust polymer network. Consequently, resultant eutectogel exhibits record‐high (20.2 MPa), toughness (62.7 MJ m –3 ), tear‐resistance (tearing energy Σ42.4 kJ –2 while possessing excellent stretchability (Σ550% strain), repairability, adhesive performance. Furthermore, this strategy proven be universally applicable various species polymers, even utilized fabricate continuous conductive fibers, demonstrating potential as engineering wearable sensors.

Language: Английский

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Solvent‐Exchange‐Assisted Wet Annealing: A New Strategy for Superstrong, Tough, Stretchable, and Anti‐Fatigue Hydrogels

Advanced Materials, Journal Year: 2023, Volume and Issue: unknown, P. 2210624 - 2210624

Published: Jan. 17, 2023

Hydrogels are widely used in tissue engineering, soft robots, wearable electronics, etc. However, it remains a great challenge to develop hydrogels possessing simultaneously high strength, large stretchability, fracture energy, and good fatigue threshold suit different applications. Herein, novel solvent-exchange-assisted wet-annealing strategy is proposed prepare performance poly(vinyl alcohol) by extensively tuning the macromolecular chain movement optimizing polymer network. The reinforcing toughening mechanisms found be "macromolecule crystallization entanglement". These have tensile strengths up 11.19 ± 0.27 MPa extremely strains of 1879 10%. In addition, energy can reach as 25.39 6.64 kJ m-2 ≈1233 J , respectively. superb mechanical properties compare favorably those other tough hydrogels, organogels, even natural tendons synthetic rubbers. This work provides new effective method fabricate superstrong, tough, stretchable, anti-fatigue with potential applications artificial ligaments.

Language: Английский

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High toughness multifunctional organic hydrogels for flexible strain and temperature sensor

Journal of Materials Chemistry A, Journal Year: 2021, Volume and Issue: 9(40), P. 23243 - 23255

Published: Jan. 1, 2021

A wearable multifunctional sensor was proposed, consisting of strain and temperature sensors, both which were fabricated by a rationally designed toughness conductive organohydrogel.

Language: Английский

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Peritoneum‐Inspired Janus Porous Hydrogel with Anti‐Deformation, Anti‐Adhesion, and Pro‐Healing Characteristics for Abdominal Wall Defect Treatment

Advanced Materials, Journal Year: 2022, Volume and Issue: 34(15)

Published: Jan. 4, 2022

Implantable meshes used in tension-free repair operations facilitate treatment of internal soft-tissue defects. However, clinical fail to achieve anti-deformation, anti-adhesion, and pro-healing properties simultaneously, leading undesirable surgery outcomes. Herein, inspired by the peritoneum, a novel biocompatible Janus porous poly(vinyl alcohol) hydrogel (JPVA hydrogel) is developed efficient defects facile yet strategy based on top-down solvent exchange. The densely smooth bottom-surface JPVA minimizes adhesion fibroblasts does not trigger any visceral adhesion, its loose extracellular-matrix-like rough top-surface can significantly improve fibroblast tissue growth, superior abdominal wall defect commercially available PP PCO meshes. With unique anti-swelling property (maximum swelling ratio: 6.4%), has long-lasting anti-deformation performance maintains high mechanical strength after immersion phosphate-buffered saline (PBS) for 14 days, enabling tolerance maximum pressure an wet environment. By integrating anti-adhesion with patch shows great prospects repair.

Language: Английский

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A Structural Gel Composite Enabled Robust Underwater Mechanosensing Strategy with High Sensitivity

Advanced Functional Materials, Journal Year: 2022, Volume and Issue: 32(25)

Published: March 19, 2022

Abstract One of the key challenges in developing gel‐based electronics is to achieve a robust sensing performance, by overcoming intrinsic weaknesses such as unwanted swelling induced deformation, signal distortion caused dehydration, and large hysteresis signal. In this work, structural gel composite (SGC) approach presented encapsulating conductive hydrogel/MXene with lipid (Lipogel) layer through an situ polymerization. The hydrophobic Lipogel coating fulfills SGC unique anti‐swelling property at aqueous environment excellent dehydration feature open‐air, thus leading long‐term ultra‐stability (over 90 days) durability 2000 testing cycles) for underwater mechanosensing applications. As result, based mechanoreceptor demonstrates high stable sensitivity (GF 14.5). Moreover, several conceptual sensors are developed unveil their profound potential monitoring human motions, waterproof anti‐counterfeiting application, tactile trajectory tracking.

Language: Английский

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Tough, Transparent, and Slippery PVA Hydrogel Led by Syneresis

Small, Journal Year: 2023, Volume and Issue: 19(14)

Published: Jan. 2, 2023

Slippery and transparent polyvinyl alcohol (PVA) hydrogels with mechanical robustness exhibit broad applications in artificial biological soft tissues, flexible wearable electronics, implantable biomedical devices. Most of the current PVA hydrogels, however, are unable to integrate these features, which compromises its performance engineering applications. To achieve such purpose, herein, a novel tactic is proposed, salting-out-after-syneresis PVA, realize mechanically robust highly slippery hydrogel. The syneresis sol first conducted form dense polymer networks, then salting-out effect tunes aggregation chains rapidly induce phase separation crystallization. resultant show transparency up 98% visible region, tribological coefficient down 0.0081, excellent properties strength, modulus, toughness 26.72 ± 1.05, 6.66 0.29 MPa, 55.21 1.62 MJ m-3 , respectively. reveal potentials, contact lens that combine remarkable lubrication, anti-protein adhesion, biocompatibility, drug-loading functions demonstrated. This strategy provides simple new avenue for developing robust, transparent, hydrated showing potential biomedicine

Language: Английский

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Progress in the mechanical enhancement of hydrogels: Fabrication strategies and underlying mechanisms

Journal of Polymer Science, Journal Year: 2022, Volume and Issue: 60(17), P. 2525 - 2542

Published: June 29, 2022

Abstract Hydrogels have become ideal materials in the nascent applications of tissue engineering, soft robots, drug delivery, and so forth. However, compared with biological tissues, inherent heterogeneous microstructure low density polymer chains make hydrogels mechanically weak, severely limiting their use as structural materials. In recent decades, order to meet mechanical requirements load‐bearing biomaterials, significant research effort been devoted improving parameters hydrogels. To achieve this goal, fiber/fabric reinforced hydrogels, double network supramolecular‐interaction‐based well‐aligned microstructures, solvent induced robust investigated. review, fabrication strategies, relationships between structure properties resulting hydrogel, underlying enhancement mechanisms various classes hydrogel summarized. Here, behind these strategies rely on creating effective networks, which are achieved by introducing a rigidly phase, synergistic distinctive features, sacrificial bonds, oriented hierarchical structures, or increased supramolecular interactions. Despite achievements toward strong tough considerable important challenges remain, such simultaneously achieving high strength, toughness, water content It is believed that already proposed will push development

Language: Английский

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Stretchable and Bioadhesive Gelatin Methacryloyl-Based Hydrogels Enabled by in Situ Dopamine Polymerization

ACS Applied Materials & Interfaces, Journal Year: 2021, Volume and Issue: 13(34), P. 40290 - 40301

Published: Aug. 19, 2021

Hydrogel patches with high toughness, stretchability, and adhesive properties are critical to healthcare applications including wound dressings wearable devices. Gelatin methacryloyl (GelMA) provides a highly biocompatible accessible hydrogel platform. However, low tissue adhesion poor mechanical of cross-linked GelMA (i.e., brittleness stretchability) have been major obstacles their application for sealing repair wounds. Here, we show that adding dopamine (DA) moieties in larger quantities than those conjugated counterparts the prepolymer solution followed by alkaline DA oxidation could result robust GelMA-based hydrogels. In this way, ∼140% stretchability ∼19 000 J/m3 which correspond ∼5.7 ∼3.3× improvement, respectively, compared controls, were obtained. The oxidization was found play an important role activating (∼4.0 ∼6.9× increase force under tensile shear modes, respectively) due presence reactive oxidized quinone species. We further conducted parametric study on factors such as UV light parameters, photoinitiator type lithium phenyl-2,4,6-trimethylbenzoylphosphinate, LAP, versus 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone, Irgacure 2959), tune cross-linking density thereby compliance better properties. superior performance resulting along vitro cytocompatibility demonstrated its potential use skin-attachable substrates.

Language: Английский

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Mechanically Robust and Transparent Organohydrogel‐Based E‐Skin Nanoengineered from Natural Skin

Advanced Functional Materials, Journal Year: 2023, Volume and Issue: 33(15)

Published: Jan. 29, 2023

Abstract Electronic skins (e‐skins), which are mechanically compliant with human skin, regarded as ideal electronic devices for noninvasive human–machine interaction and wearable devices. In order to fully mimic e‐skins should possess reliable mechanical properties be able resist external environmental factors like heat, cold, desiccation, bacteria, while perceiving multiple stimuli, such temperature, humidity, strain. Here, a transparent, robust, environmentally stable, versatile natural skin‐derived organohydrogel (NSD‐Gel) is nanoengineered through the integration of betaine, silver nanoparticles, sodium chloride in glycerol/water binary solvent. The transparent NSD‐Gel e‐skin exhibits outstanding tensile strength (7.33 MPa), puncture resistance, moisture retention, self‐regeneration, antibacterial properties. Additionally, possesses enhanced cold/heat resistance stimuli‐responsive characteristics that effectively sense temperature humidity changes, well physiological body motion signals. vitro vivo experiments show confers desired biocompatibility tissue protective even extremely harsh environments (−196 °C 100 °C). has great potential applications multidimensional devices, human‐machine interfaces, artificial intelligence, generating platform development high‐performance on‐demand

Language: Английский

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