A breathable and highly impact-resistant shear-thickened fluid (STF) based TENG via hierarchical liquid-flow spinning for intelligent protection

Impact resistant and force-sensitive yarns are the crucial components of intelligent wearable protective textiles. However, it is still a challenge to combine liquid impact resistant materials with yarns. In this paper, shear-thickened fluid (STF) based hierarchical wrapping core-spun yarns were produced by liquid flow spinning for the impact resistance and intelligent monitoring, which exhibited multi-superiority of protectivity, sensitivity, flexibility, breathability and washability. In terms of protection, STF fabric (STFF) performed improved impact resistance and energy absorption capacity, absorbing 73.5 % of the applied force. Numerically simulation analysis indicated that energy dissipation mechanism of STFF could be ascribed to the combination of the yarn surface deformation and STF core shear thickening of STF yarn (STFY). The STFF was still skin-friendly without breakage and leakage after 10,000 times cyclic friction. Its air permeability was up to 189 mm/s. Moreover, a STFF-based TENG was constructed by weaving with Kevlar yarn, which showed self-powered sensing ability to recognize impact force with great durability over 10,000 cycles. For energy harvesting, the fabric exhibits excellent triboelectric performance of 22 V open-circuit voltage (VOC), 225 nA short-circuit current (ISC), and 30 nC short-circuit transferred charge (QSC). In addition, STF-based TENG fabric enables the sensing of various forces, frequencies and different contact materials. Finally, the early warning, protection, motion monitoring and energy harvesting of STFF for intelligent protective applications were demonstrated, opening new avenues for the sensing function integration of protective textiles.