Solvent-assisted electrospun fibers with ultrahigh stretchability and strain sensing capabilities

Abstract

Large strain flexible strain sensors have recently been the focus of many studies due to their wide range of applications in wearable technologies. However, development of a thin, conformable, and flexible strain sensor with a high maximum stretchability and a high gauge factor has still remained a challenge. In resistive-type sensors specifically, there is a trade-off between these two competing factors which has left a gap in development of large strain flexible strain sensors. To increase the sensitivity of the sensor, tuning the microstructure of the sensor through introducing a larger surface area is suggested. Using a solvent-assisted electrospinning technique and a highly stretchable copolymer of styrenebutadiene-styrene, super elastic mats composed of microfibers with a large surface area are obtained. Coating the fibers with different conductive materials and coating methods, a flexible strain sensor able to detect up to 1000% strain is fabricated. The sensors also show low hysteresis under cyclic-induced applied loadings.