Zwitterionic dynamic elastomer with high ionic conductivity for self-adhesive and transparent electronic skin

High electric conductivity in combination of stretchability has been in pursuit for soft conductors in applications of flexible electronics. Polyionic elastomers, though showing superiority to conductive composite elastomers in transparency and stretchable conductivity, hydrogels and ionogels in maintaining performance under evaporation and compression, frequently had their conductivities limited below the level desired by many applications, and suffered from tedious preparation, limited functions, especially non-recyclability. Herein, an unprecedented zwitterionic polyionic elastomer with dynamic backbone was designed to achieve a super high ionic conductivity of ∼ 0.23 S/m and fully recyclability. It not only exhibited super stretchability of ∼ 600%, but also had its ionic conductivity maintained under stretching. Besides self-adhesion and self-healing, its dynamic feature also offered photo/thermal-driven remoldability and recyclability. When serving as smart electronic skin, it was sensitive enough to detect cyclic strains of 0.2 ∼ 500% with stability. By incorporating into an AC circuit, it could also serve as a pressure-independent touch sensor to detect human touch. Thus, this study not only provides an unprecedentedly dynamic zwitterionic elastomer to fully recyclable ionic conductivity, but also promises a super platform of soft conductor for applications in human–machine interfaces of soft and stretchable electronics.