In this study,w ed eveloped as uperstrong and reversible adhesive,whichcan possess ahigh bonding strength in the "adhesive" state and detach with the application of heating.A ni onic crystal (IC) gel, in whicha nI Cw as immobilized within as oft-polymer matrix, were synthesized via in situ photo-crosslinking of aprecursor solution composed of N, N-dimethyl acrylamide (DMAA) and am elted IC.T he obtained IC gel is homogenous and transparent at melt point. When cooled to the phase transition temperature of the IC,the gel turns into the adhesive with the adhesion strength of 5.82 MPa(on glasses), due to the excellent wetting of melted gel and at hin layer of crystalline IC with high cohesive strength formed on the substrates.T he synergistic effects between IC, polymer networks and substrates were investigated by solid state 1 HNMR and molecular dynamics simulation. Sucha n adhesive layer is reversable and can be detached by heating and subsequent re-adhesion via cooling. This study proposed the new design of removable adhesives,w hich can be used in dynamic and complex environments.

Muscles and some tough hydrogels can maintain perfect mechanical properties after millions of loading cycles owing to the anisotropic microstructures inside them. However, applications of intrinsic anisotropic microstructures in biological tissues and tough hydrogels are limited by the poor mechanical performance in the perpendicular direction relative to the alignment direction. Here, a universal strategy is proposed for developing hydrogels with unprecedented isotropic crack propagation resistance only depending on the interpenetrating entanglements of polymer chains (polyacrylamide (PAAM) or poly‐(1‐acrylanmido‐2‐methylpropanesulfonic acid) (PAMPS)) in deformable polymeric microspheres (PAMPS or PAAM). The deformable interpenetrating network in microspheres can transform the hydrogel from isotropic to anisotropic instantaneously in any load direction, and effectively alleviate the stress concentration at the crack tip, dissipate energy, and eliminate notch sensitivity. The best isotropic hydrogel displays an ultimate strain of 5300%, toughness of 18.9 MJ m–3, fracture energy of 157 kJ m–2, and fatigue threshold of 4.2 kJ m–2. Furthermore, the mechanical strength of hydrogels can be simply tuned by solvent replacement. The strategy presented here can be expanded to prepare other isotropic hydrogels with super tear‐resistant and anti‐fatigue properties, based on a wide variety of deformable microspheres and matrix polymers.

The development of aqueous metal-ion batteries has attracted great attention due to their relatively low cost and high safety levels. However, their practical applications are hindered by the ease at which their aqueous electrolytes freeze. Inspired by the antifreezing properties of salts and alcohol cryoprotective agents, a "two-in-one" cryoprotective agent, hydroxyl-functionalized poly( ionicliquid) (PIL-OH)-based hydrogel electrolyte for aqueous lithiumion batteries (ALIBs) is developed. The synergy of both ionic hydration and hydrogen bond interactions between the PIL-OH and water molecules impairs the hydrogen-bond networks of water and depresses the freezing point of water below −80 °C. Benefiting from exceptional ultralow temperature tolerance, the prepared PIL-OH hydrogel exhibits a highly enhanced low temperature adaptability and a high ionic conductivity of 0.08 mS cm −1 at −80 °C. The PIL-OH hydrogel-based flexible ALIBs exhibit high flexible durability and good cycling stability with 93% capacity retention over 200 cycles at −80 °C. The PIL-OH hydrogel report herein opens up new opportunities for practical applications of wearable and flexible aqueous batteries at ultralow temperature environments, such as the North and South Poles.

In this study,w ed eveloped as uperstrong and reversible adhesive,whichcan possess ahigh bonding strength in the "adhesive" state and detach with the application of heating.A ni onic crystal (IC) gel, in whicha nI Cw as immobilized within as oft-polymer matrix, were synthesized via in situ photo-crosslinking of aprecursor solution composed of N, N-dimethyl acrylamide (DMAA) and am elted IC.T he obtained IC gel is homogenous and transparent at melt point. When cooled to the phase transition temperature of the IC,the gel turns into the adhesive with the adhesion strength of 5.82 MPa(on glasses), due to the excellent wetting of melted gel and at hin layer of crystalline IC with high cohesive strength formed on the substrates.T he synergistic effects between IC, polymer networks and substrates were investigated by solid state 1 HNMR and molecular dynamics simulation. Sucha n adhesive layer is reversable and can be detached by heating and subsequent re-adhesion via cooling. This study proposed the new design of removable adhesives,w hich can be used in dynamic and complex environments.

Tough and self‐healable substrates can enable stretchable electronics long service life. However, for substrates, it still remains a challenge to achieve both high toughness and autonomous self‐healing ability at room temperature. Herein, a strategy by using the combined effects between quadruple H‐bonding and slidable cross‐links is proposed to solve the above issues in the elastomer. The elastomer exhibits high toughness (77.3 MJ m−3), fracture energy (≈127.2 kJ m−2), and good healing efficiency (91 %) at room temperature. The superior performance is ascribed to the inter and intra crosslinking structures of quadruple H‐bonding and polyrotaxanes in the dual crosslinking system. Strain‐induced crystallization of PEG in polyrotaxanes also contributes to the high fracture energy of the elastomers. Furthermore, based on the dual cross‐linked supramolecular elastomer, a highly stretchable and self‐healable electrode containing liquid metal is also fabricated, retaining resistance stability (0.16–0.26 Ω) even at the strain of 1600 %.