Thin-Film Temperature Sensor on Flexible PEEK Fabric

Plastic-based threads are widely and commonly used materials for the development of fabrics and textiles in a broad field of applications. Thanks to the properties of these materials, including mechanical flexibility, low weight, and breathability, it is possible to expand their functionality, through the integration with electronic devices, for sensing, actuation, or data transmission. In this work, a commercial fuel filtering fabric of Polyether ether ketone (PEEK) was used for the first time as a substrate for the fabrication of thin-film temperature sensors. The devices were tested and characterized over a temperature range from 20 °C to 60 °C (at a constant relative humidity of 30 %), showing a temperature coefficient resistance $\alpha$ of $2\times 10^{-30}{}^{\circ}\mathrm{C}^{-1}$. In addition, device functionality is demonstrated down to 27 mm bending radius, and in real-time, while water vapor is blown through the fabric, with no performance variation. The development of these devices represents the first demonstration of thin-film temperature sensors directly fabricated on PEEK-based fabrics, paving the way for functionalized and smart membranes and threads, with possible applications in automotive, fuel, and gas filtering monitoring.