A multifunctional thermochromic–elastomeric composite for integrated pressure and temperature sensing

Abstract

The growing demand for flexible and multifunctional sensors has driven the development of functional materials that can simultaneously respond to multiple and diverse stimuli, including mechanical stress and changes in temperature. In this work, we report the development of a multifunctional composite dielectric material combining thermochromic polydiacetylene (PDA) and styrene–ethylene–butylene–styrene (SEBS) for use in flexible capacitive pressure sensors. To further enhance pressure sensitivity, the dielectric layer was patterned with Mesoamerican pyramid (MAP) microstructures, which amplify mechanical deformation and increase effective contact area. It also shows the soft molding fabrication capability of the composite. The composite demonstrates excellent mechanical resilience, maintaining stable capacitance over 10 000 loading cycles at 220 N, and exhibits thermally responsive behavior, with reversible color transitions at 45 °C and irreversible changes at 90 °C. The resulting sensors display reliable performance across a broad dynamic range of pressure and temperature, making them well-suited for applications in wearable electronics, biomedical monitoring, and smart human–machine interfaces. This work highlights the potential of combining structural patterning with functional composites to engineer responsive and robust soft sensing platforms.