Lightweight and highly compressible/stretchable ionogel foams for designing pressure and strain sensors

Strain sense and pressure sense are the two essential functions of wearable electronics and electrical skins. However, there is still lack of a single material that can be used to detect strain and pressure simultaneously since both the high stretchability and compressibility are normally hard to be integrated into one material. In this paper, we fabricated an ionogel foam by one-step foaming of polyurethane (PU) and the subsequent ultrasonic loading of ionic liquid (IL). The as-prepared IL@PU ionogel foam exhibits outstanding stretchability (275 %) and compressibility (99 %), which can be used to design high-performance strain sensors and pressure sensors. This work provides a simple but effective avenue for the fabrication of strain/pressure sensing materials, which has great potential in wearable electronics and electronic skins.