Preparation of high performance electrospun TPU fiber films piezoresistive sensor with a fabric microstructure by hot-press imprint method

To enhance the device-performance and stability of flexible strain sensor, the graphene (Gr), polyaniline (PANI) and Gr/PANI were loaded on the electrospun thermoplastic polyurethane (TPU) fiber film, respectively. Subsequently, the surface microstructure of a commercial fabric was transferred to the surface of the electrospun TPU fiber film by hot-press imprint method. And a serial of flexible piezoresistive sensors with surface and internal microstructures were assembled. After systematically studying the effects of filler types and hot pressing time on the sensor performance, the Gr/PANI-TPU (MGPT) sensor with excellent sensing performance was obtained. Compared to the other sensors, the MGPT sensor has wide response rate range (1-1000 mm·min⁻¹) and high sensitivity of 0.143 kpa⁻¹ under pressure range of 0-6 kPa. It also has fast response time (153 ms) and recovery time (106 ms) and excellent durability (1000 cycles of loading-unloading), showing good motion monitoring ability in human applications.