Water-repellent and self-repairing capabilities integration: Enhancing longevity and practicality of fabric-based flexible devices

This study delineates the development of a versatile and flexible heater achieved through the sequential coating of polycaprolactone (PCL) fibers with MXene, silver nanowires (AgNW), and Aerosil/polydimethylsiloxane (AP). The primary innovation of this research lies in the concurrent realization of self-healability at low temperatures and exceptional mechanical flexibility, biocompatibility, and robust superhydrophobicity-based waterproof properties. PCL, recognized for its biocompatibility, demonstrates self-healing capabilities under mild thermal conditions, while the MXene layer mitigates damage and deformation during the healing process by providing thermal stability and efficient heat dissipation. AgNW significantly enhances electrical conductivity, thereby facilitating efficient Joule heating. The AP layer, introduced for the first time in wearable fibrous devices, imparts superior water-repellent properties by forming a hydrophobic surface that repels water and prevents moisture penetration, effectively safeguarding the electrode material from humid environments and acidic solutions. Comprehensive evaluations indicate that the heater maintains stable electrical and thermal properties, even after enduring 50,000 cycles of bending at a radius of curvature of 500 μm, 100 h of washing, and multiple cycles of cutting and healing. The fabric-based heaters were seamlessly integrated into commercially available arm sleeves, preserving their heating functionality despite being subjected to bending motions.