A Conformable Shape-Stable Self-Healing Polymer Platform for Continuous Wireless Arterial Pulse Monitoring

Self-healing polymers offer softness and conformability suitable for skin-interfaced electronics. However, their flowable nature often leads to gradual shape deformation, making them unsuitable for circuit-integrated devices that require structural stability. Here, we introduce a shape-stable self-healing polymer (SS-SHP) featuring a branched polymer network reinforced with reversible imine and hydrogen bonds. The SS-SHP maintained its original shape for 20 days with less than a 5% reduction in storage modulus. In addition, its low Young’s modulus of 576 kPa, comparable to that of skin, allowed conformal contact with microtextured skin surfaces. By embedding Ag flakes into the SS-SHP matrix, we developed a self-healing conductor that showed stable surface resistance over time, avoiding the conductivity degradation typically observed in conventional SHPs. Utilizing the SS-SHP as both the substrate and the electrode matrix, we fabricated a wireless arterial pressure sensor integrated with an optical signal transmission circuit. Due to the skin-like softness of the SS-SHP, the device conformed intimately to the wrist without external contact pressure, enabling precise detection of arterial pulse signals and distinguishing between pulse waveforms from a healthy subject and a pregnant individual. The system successfully translated dynamic pressure fluctuations into real-time optical signals, allowing continuous monitoring of physiological activity through a compact and skin-conformal platform.