A Reprocessable Dynamic Disulfide Hydrogel for Capacitive Pressure Sensors

With the rapidly growing demand for wearable sensor devices across a range of applications, sensing technology has been rapidly advancing. However, challenges such as limited sensitivity, device instability, and trade-offs between performance and recyclability remain unaddressed. We report the facile fabrication of a recyclable dynamic disulfide hydrogel from an amphiphilic polyethylene-glycol-based thioctic acid derivative with hydrophilic/hydrophobic characteristics. The hydrogel demonstrates decent thermal stability and adequate mechanical properties, including elasticity, compressibility, and reprocessing capability. It is also integrated into a microstructured capacitive sensor, demonstrating a sensitivity of up to 1.14 kPa^-1, rapid response times within 20 ms, and robust functioning stability up to 400 consecutive cycles. These properties make it particularly intriguing for the sustainable development of high-performance wearable sensors.