Multi-functional STF-based yarn for human protection and wearable systems

Recently, smart wearable devices with anti-impact property and intelligent monitoring function have attracted more and more attention. Herein, hollow silicone rubber tube, shear thickening fluid (STF), carbon nanotubes (CNTs), and Polydimethylsiloxane (PDMS) coating were used to prepare a kind of multi-functional intelligent yarn (C-STF-based yarn) with excellent energy dissipation performance. Due to the unique rheological properties of STF, the dissipated energy of the yarn during the compression process increased with the enhancement of shear thickening effect of STF. The mechanism was discussed by numerical simulation. In addition, as a flexible fiber sensor, it could respond to a variety of mechanical stimuli, such as stretching, compression, and bending. Moreover, smart fabric woven by C-STF-based yarns had excellent impact resistance and impact monitoring function. Meanwhile, the smart fabric could also sense various joint movements of the human body, such as walking, running, and jumping. Therefore, this study provided a feasible method for the construction of multi-functional intelligent fabric, which had broad application prospects in human safe-guarding and real-time motion monitoring.