Enhancement of Strain‐Sensing Performance through Gas Phase Incorporation of Siloxane into Thermoplastic Polyurethane‐Conducting Polymer Composite

Abstract

AbstractIn this study, thermoplastic polyurethane (TPU)‐conducting polymer (CP)–SiO2 hybrid strain sensors are fabricated via the simultaneous co‐vaporization of a CP monomer with tetraethyl orthosilicate (TEOS). Poly(3,4‐ethylenedioxythiophene) (PEDOT) and polypyrrole (PPy) hybrids prepared using the oxidant, iron (III) p‐toluenesulfonate hexahydrate (FTS) with TPU as the substrate are explored along with the effect of hybridization on their sensing performance and mechanical properties. The SiO2 is mostly formed on the surface and the CP is successfully polymerized within the TPU matrix. The sensor can be stretched further by up to 290% more than the pristine counterpart. Moreover, stretch‐release cycles show an increase in the relative resistance of the sensor by up to 89%, thereby improving its sensitivity. The sensors can detect motion at various strain levels, different speeds, and continuous deformation at different strains. The sensor’s reliability is tested by up to 1000 cycles at 10% strain, as well as other kinds of distortion such as bending and twisting. The created organic‐inorganic hybrid sensor exhibits a synergistic enhancement of both its mechanical properties and electromechanical performance. Furthermore, the processability of the elastomer and the versatility of the incorporated siloxane component have allowed the homogeneous distribution of the active elements (PEDOT, PPy).