Flexible, Quickly Responsive, and Highly Efficient Carbon Nanotube/Thermoplastic Polyurethane Composite Yarn for Multifunctional Wearable Devices

Abstract

The advancement of next-generation wearable electronics is highly inclined with electro-conductive yarn having excellent flexibility and functionality. However, the deficiency of existing metal-based and nanomaterial (carbon nanotube, i.e., CNT)-based conductive wires indeed limits their modest requirements due to inadequate elasticity and mediocre antiabrasion ability in conjunction with stable electrothermal performance for enough effective utilization in real textiles. This study introduces an interesting approach to overcome the extant issue by encapsulating CNT yarn with a thin, even shield of textile polymer, i.e., TPU (thermoplastic polyurethane), combining two simple operations of polymer infiltration and twisting. Two different concentrations% of TPU solution (5 and 10%) were selected, and twisted CNT yarn was prepared. Compared to pristine CNT yarn, 5% TPU-CNT yarn possesses brilliantly enhanced tensile strength (+241%), stretchability (+125%), exceptional tensile force (+216%), and extraordinary antiabrasive performance (+1752%). In addition, the good range strain sensitivity (∼39%), stable electromechanical prominence during 28 cyclic loading at 6% tensile strain, and outstanding electrothermal stability (for 200 s) reaching the temperature of 228 °C only within ∼10 s by low driving voltage (2 V) simply represent its high efficacy to satisfy the prerequisite regarding comfort wear and steady conduction for wearable electronics. The potential demonstrations of deicing of ice by CNT/TPU yarn embedded 3D spacer woven composites with 58 times weight ratio within 9.6 min just signify its exceptional E-thermal performance. The wellenough mechanical harmony with schemes and robustness over periodical usages of as-developed highly flexible and sewable TPU-CNT yarn opens up its promising prospects for new-generation smart clothing as well as multifunctional composites.