A Rational Design of Bio‐Derived Disulfide CANs for Wearable Capacitive Pressure Sensor

Abstract Classic approaches to integrate flexible capacitive sensor performance are to on‐demand microstructuring dielectric layers and to adjust dielectric material compositions via the introduction of insoluble carbon additives (to increase sensitivity) or dynamic interactions (to achieve self‐healing). However, the sensor's enhanced performances often come with increased material complexity, discouraging its circular economy. Herein, a new intrinsic self‐healable, closed‐loop recyclable dielectric layer material, a fully nature‐derived dynamic covalent poly(disulfide) decorated with rich H bonding and metal‐catechol complexations is introduced. The polymer network possesses a mechanically ductile character with an Arrhenius‐type temperature‐dependent viscoelasticity. The assembled capacitive pressure sensor is able to achieve a sensitivity of up to 9.26 kPa⁻¹, fast response/recovery time of 32/24 ms, and can deliver consistent signals of continuous consecutive cycles even after being self‐healed or closed‐loop recycled for real‐time detection of human motions. This is expected to be of high interest for current capacitive sensing research to move toward a life‐like, high performance, and circular economy direction.