Robust Multi-layer Kevlar Aerogel for High Performance Force Sensor

To meet the increasing application of wearable force sensors, there is an urgent demanding for developing flexible and light-weight base materials for the application. To improve the detection limit of the force sensors, the mechanical strength of base material needs to be optimized. Kevlar nanofibers are great candidates for fabricating aerogels due to the lightweight, great thermal stability and good compatibility to multiple nanofiller. But single layer Kevlar-based aerogel film is fragile and easily disturbed by environmental conditions. Here in, we develop an assemble strategy to fabricate multilayer aerogel film. Single layer aerogel film is fabricated by blade-coating and freeze-drying strategies with different nanofiller to functionalize the aerogel film. Different functional layer stack, with Kevlar nanofiber dispersions with lower density filling in the interlayer. Then the aerogel was hot-pressed and dried. The multi-layer aerogel film exhibits great mechanical strength, with an improvement of 27% and 166% of strain and stress, respectively. The construction of the multi-layer aerogel indicates a great potential in wearable force sensors.