Synthesis and Fabrication of Supramolecular Polydimethylsiloxane-Based Nanocomposite Elastomer for Versatile and Intelligent Sensing

High-performance strain sensors featuring self-healing ability and high stretchability are desired for human motion detection, soft robotics, and diver intelligent applications. Herein, a novel self-healing elastomer was synthesized via a facile one-pot polycondensation reaction between bis(3-aminopropyl) terminated polydimethylsiloxane and 2,4'-tolylene diisocyanate, followed by introducing carboxyl-functionalized multiwalled carbon nanotubes (CNTs). The physically entangled linear molecular chains and multiple hydrogen bonds endowed elastomer with a remarkable healing efficiency of 98.1% and outstanding stretchability of over 1000%. Owing to the conductive network constructed by the uniformly dispersed CNT, the nanocomposite elastomer-based strain sensor achieved a high gauge factor of 2.43 and its sensing performance could be well regained after self-healing. The strain sensor was successfully used for detecting various human motions and distinguishing facial microexpressions. Moreover, the nanocomposite elastomer applied on a grip ball and woolen glove as sensing units rendered them with the ability of grip force detection and sign language recognition. This work offers a new route and a promising self-healing nanocomposite elastomer for the development of recyclable and sustainable high-performance strain sensors and prospects its advanced intelligent applications.