Heat-resistant core-sheath yarn sensor with high durability and thermal adaptivity for fire rescue

Although many flame-resistant yarn-based sensors have been widely investigated in firefighting clothing, undesirable thermomechanical stability and significant sensor cross-interference have limited their practical application in high-temperature environments. Here, a heat-resistant core-sheath yarn (HRCSY)-based flexible sensor is fabricated using conductive flame-retardant viscose yarns as the core layer and helically wrapped polyimide fibers as the sheath layer. Benefiting from the core-sheath structure design and a special lock-stitched structure, the HRCSY sensor shows ultralow thermal deformation and dynamic mechanical stability and thus can exhibit high durability after 15,000 compression test cycles and stable functionalization at high temperatures up to 400°C. In addition to stably monitoring human motions, the HRCSY sensors incorporated into thermal gloves can recognize simple objects with different shapes and weights in high-temperature environments. It can be expected that the HRCSY sensor will considerably advance the future development and practical application of smart textiles in high-temperature environments.