Graphene/siloxane composite coated auxetic textiles for next-generation flexible piezoresistive sensors

This work presents the development of a novel piezoresistive strain sensor based on plied auxetic yarn (PAY) using graphene/siloxane composite conductive ink. The core of the sensor's design is the use of braided yarn made from a Lycra and cotton yarns blended core-spun yarn, which provides the foundation for the auxetic properties exhibited by the sensor. The application of siloxane coating significantly augments the mechanical stability and durability of the yarn. The introduction of conductive graphene ink optimizes the electrical properties of sensors. This novel composite develops a superior negative Poisson’s ratio in sensors along with substantial improvement of sensitivity and strain range. The piezoresistive strain sensors (PSS) fabricated in this work developed a marked enhancement in performance with the ability to efficiently translate mechanical strain into measurable electrical resistance changes, thus offering promising applications in health monitoring, structural diagnostics, and soft robotics.