A Simple Physical Kneading Strategy to Prepare an Ultrahigh-Stretchable Conductive Starch/Poly(vinyl alcohol)/Borax/Carbon Nanotube Hydrogel for Flexible Capacitive Electronics

With the continuous development of technology, the application prospects of hydrogels as flexible electronic materials are becoming increasingly widespread. However, developing a high-performance, environmentally friendly hydrogel for flexible electronics remains a challenge. In this study, starch coupled with poly(vinyl alcohol) (PVA), borax, and carbon nanotubes (CNTs) was used as the raw material to prepare the environmentally friendly biomass-based conductive starch/PVA/borax/CNT (Starch@PB@CNT) hydrogel through a simple physical kneading strategy. The hydrogel exhibited remarkable stretchability (>10000%), good self-healing performance, outstanding adhesion to different substrates, biodegradability, and considerable conductivity. It could be assembled into the flexible capacitive strain sensor devices and could be used for detecting and collecting human movement signals. This simple and efficient method not only contributes to fully exploring the development potential of starch-based materials, but also brings possibilities for the application of flexible wearable devices.