Transparent and healable ionogels with very high mechanical strength, ionic conductivity, and resilience were fabricated for use as strain sensors with satisfactory reliability. The ionogels were fabricated by casting an aqueous solution of poly­(vinyl alcohol) (PVA)–poly­(vinylpyrrolidone) (PVP) complexes and 1-ethyl-3-methylimidazolium dicyanamide ([EMIm]­[DCA]), followed by evaporation of water at room temperature. The use of [EMIm]­[DCA] endowed the resulting ionogels with ionic conductivity at room temperature as high as 19.7 mS cm–1. Owing to the synergy between the abundant number of hydrogen bonds between PVA and PVP and the crystallized PVA segments that served as nanofillers, the resulting ionogels had good mechanical properties with a tensile stress of 7.7 MPa, a strain of 821%, and good resilience. In addition, the resulting ionogels showed rapid and repeatable sensing signals over a wide strain range (0.1–400%). This enabled them to detect both vigorous muscle movements, such as walking and jumping, and subtle muscle movements, such as pulse. Moreover, owing to the reversibility of hydrogen bonds, physically damaged mechanical properties, conductivity, and sensing ability of the ionogels could be conveniently healed with the assistance of water.

Electrically conductive fabrics with liquid repellency and corrosive resistance are strongly desirable for wearable displays, biomedical sensors, and so forth. In the present work, highly electrically conductive and healable superamphiphobic cotton fabrics are fabricated by a solution-dipping method that involves (NH)PdCl-catalyzed electroless deposition of Cu and the subsequent deposition of a mixture of fluorinated-decyl polyhedral oligomeric silsesquioxane (F-POSS) and 1 H,1 H,2 H,2 H-perfluorooctyltriethoxysilane (POTS) on cotton fabrics. Because of their superamphiphobicity, the resulting fabrics are self-cleaning and exhibit excellent resistance against corrosive acidic and basic solutions. The as-prepared fabrics have a sheet resistance of ∼0.33 Ω·sq and show excellent electromagnetic interference shielding and electrothermal heating ability. Because of the preserved F-POSS and POTS molecules, the fabrics can conveniently and repeatedly restore the loss of superamphiphobicity by applying a low voltage of 1.0 V or heating the fabrics at 135 °C to facilitate the migration of the preserved F-POSS and POTS to the surface of cotton fabrics. The integration of healable superamphiphobicity into the Cu-coated fabrics generates multiple functional cotton fabrics with excellent conductivity, electromagnetic interference shielding, self-cleaning ability, and significantly enhanced durability.

Healable oil-repellent antifogging films are fabricated by layer-by-layer assembly of hyaluronic acid (HA) and branched poly(ethylenimine) (bPEI), followed by immersion in the aqueous solutions of perfluorooctanesulfonic acid potassium salt (PFOS). The loading of PFOS endows the HA/bPEI films with oil repellency while maintaining its original hydrophilicity. The resulting films have an excellent antifogging ability, and various organic liquids can easily slide down the slightly tilted films (<10°) without any residue. Through water-assisted migration of PFOS and polyelectrolytes, oil-repellent antifogging films are able to repetitively and autonomously recover their damaged oil repellency and transparency caused by plasma etching, cutting, or scratching, prolonging their life span. The as-developed healable oil-repellent antifogging films have potential application as antifingerprint coatings for touch screens, antigraffiti coatings for signs and shop windows, and antifogging coatings for lenses, mirrors, and windshields.

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