Stimuli-Responsively Conductive Ag/P(NIPAM-co-AA) Particles for Tailoring Textile Sensors

Creating soft sensors is a significant research topic in the field of sensors. Electric micro/nanoparticles have special advantages in constructing various soft sensors, e.g., textile sensors, in which the control of their electric conductivity is a key problem. Here, the electric conductivity and the temperature-responsive conductivity of Ag/poly(N-isopropylacrylamide-co-acrylic acid), i.e., Ag/P(NIPAM-co-AA), hybrid microgel particles can be obtained and controlled, and the size and density of silver nanoparticles (AgNPs) in hybrid microgel particles can be tuned since the correlation between the carboxyl group of AA and AgNPs in situ produced the microgel. Their electric conductivity can be retained even when these hybrid microgel particles are dried and manufactured into fabrics. Upon applying pressure, the hybrid microgel particles-integrated textiles display high sensitivity (−30% under 1 N force) in electric resistance, characterized by an exponential decay pattern. To showcase its potential applications, we fabricated a textile-based sensor using these hybrid microgel particles for effectively monitoring human joint movements. The control of particle conductivity will have wide potential applications in advanced wearable sensors and smart textiles.