Intrinsic fiber reinforced polyimide aerogel flexible strain sensor applied in high-temperature environment
Jinming Liu, Ling Weng, Xiaorui Zhang, Xiaoming Wang, Zijian Wu
Abstract
Flexible strain sensors have garnered significant attention for their potential applications in advanced flexible electronics and wearable technologies. However, achieving stable signal transmission at high temperatures remains a major challenge. In this study, we developed a novel polyimide (PI) aerogel composite, reinforced with intrinsically short-cut polyimide nanofibers (PINF) that are surface-coated with silver nanoparticles to enhance both conductivity and mechanical strength. Carbon nanotubes (CNTs) are used as the main filler in synergistic effect with Ag@PINF particles to further improve the conductivity and sensing performance of the composite material. This synergistic design results in a flexible PI aerogel composite material with rapid response time (116 ms), high sensitivity (GF = 3.12), and long-term cycling stability (> 1000 cycles). Additionally, the sensing materials were tested at high temperatures and after high-temperature aging, demonstrating good flexible sensing performance. Experimental results demonstrate that the composite sensor maintains stable strain-sensing performance across a range of environmental temperatures, showing consistent strain response under the same deformation conditions. This work provides a promising approach for fabricating high-performance, temperature-resistant flexible strain sensors, with broad applications in flexible electronics and wearable technologies.