Elastic Aerogel with Tunable Wettability for Self-Cleaning Electronic Skin

Lightweight aerogels with elastic performance and tunable surface properties have made them a good alternative for smart electornic skin. However, the aerogels remain a great barrier for sensing applications because of their severe brittleness and difficult regulation of surface property. Herein, we report a superelastic aerogel originated from a rational designed waterborne poly(siloxane-benzoxazine) by using the ice template method. The three-dimensional (3D) network is constructed via the radical crosslinking and ring-opening polymerization followed by the freeze-drying process. Moreover, it also shows pronounced mechanical performance that can be compressed over 70% and recover without fracture. Beyond that, its surface property could be altered from highly hydrophilic to hydrophobic property (145° water contact angle) by adjusting the crosslinking degree of the aerogel under different curing temperatures. We further demonstrate a pressure sensor by in situ polymerization of the aniline (PANI) on the surface of the aerogel. The multifunctional properties make it an attractive material for self-cleaning electronic skin.