Stretchable, environmentally stable, multifunctional ionogel with self-healing and adhesive properties for high-performance flexible sensors

Conventional hydrogels integrated into sensor technologies face insufficient synergy between mechanical adaptability, conductive sensitivity, self-adhesion and self-healing. Therefore, we prepared an ionogel by photoinitiated polymerization using 1-butyl-3-methylimidazolium bis(trifluoromethanesulfonimide) salt ([BMIM][TFSI]) as the dispersing medium and ethyl 2-[[(butylamino)carbonyl]oxo]acrylate (PBA) and N,N-dimethylacrylamide (DMAA) as the monomers, which possess high stretching, high electrical conductivity, self-healing adhesion and remain very soft in extreme environments while being able to be twisted at will. The rich chemical cross-linking and physical cross-linking in the ionogel endows it with excellent fracture strength and elongation at break at room temperature, while its deformation durability is very strong, tensile/release cycling 5000 times still shows stable resistance change, and it has a good self-repairing ability, and its repairing efficiency can reach more than 90 % after 12 h of repairing at 20 ℃. In addition, the addition of fluorinated ionic liquids resulted in excellent environmental stability, virtually unchanged quality for 21 days in an 80 °C oven as well as strong adhesion to different substrates. The ionogel designed in this work have promising applications in wearable devices and electronics. © 2024 Elsevier B.V.