Smart textiles for human–machine interface fabricated via a facile on-site vapor-phase polymerization

Abstract

Conducting polymers are widely employed in wearable sensing devices. Their unique compliance and flexibility endow higher tolerance to signal aberrations caused by mechanical mismatch compared to their rigid counterparts. Mostly, wearable sensing devices composed of organic electronic materials are fabricated on smooth-treated substrates and by utilizing complex assembly processes to ensure working validity. Thus, the direct surface functionalization of textiles places a high demand for the integration of the sensing structure. The conventional surface functionalization strategies, such as dip-coating or printing, suffer from large-scale roughness as displayed by the densely woven structure and poor wettability in some textiles, and exhibit inhomogeneity and weak mechanical–electrical stability. Herein, a facile vapor-phase polymerization (VPP) strategy for a highly conductive PEDOT:Tos coating was demonstrated for the direct surface functionalization of various yarns and fabrics, enabling the in situ fabrication of electronic textiles while allowing maintaining the inherent advantages of textiles, such as flexibility and mechanical stability. We successfully fabricated strain sensors and three-dimensional (3D) fabric switches by depositing PEDOT:Tos on the surfaces of commercial yarns and fabrics, respectively. The fabricated devices exhibited excellent conductivity, uniformity (linear resistance with length), and impressive mechanical–electrical stability. Further, we constructed human–machine communication interfaces based on electronic yarns and 3D fabrics, and explored their applications in tactile sensing, fabric electronic switches for smart homes and fabric computing.