Skin-Inspired Thermosensitive Tactile Sensor Based on Thermally Conductive and Viscous Interface Composites for Rocks

Achieving high thermal conductivity and exceptional interfacial adhesion simultaneously in thermosensitive tactile recognition sensors poses a significant challenge. A copolymer, poly([[(butylamino)carbonyl]oxy]ethyl-ester)-co-polydimethylsiloxane (referred to as PP), is synthesized and subsequently complexed with alumina particles coated with liquid metal (LMAl₂O₃) to prepare a composite material called PP/LMAl₂O₃ with high thermal conductivity and strong interfacial adhesion to address this challenge. The best thermal conductivity (4.43 W m⁻¹ K⁻¹), electrical insulation (10⁻⁶–10⁻⁷ S m⁻¹), and adhesion properties derived from hydrogen bonding (1316 N m⁻²) are obtained by adjusting the volume fraction of PP and LMAl₂O₃ in PP/LMAl₂O₃. PP/LMAl₂O₃ with high thermal conductivity and high interface adhesion can efficiently transfer heat between thermal flux sensors and the objects being sensed, reliably detecting small thermal flux variations and ensuring accurate thermal flux measurements. In this study, PP/LMAl₂O₃ is used to make up thermosensitive tactile sensor. Surprisingly, PP/LMAl₂O₃ demonstrates high thermal signal sensitivity for tactile recognition applications, allowing the smart thermosensitive tactile sensor system to distinguish unknown rock materials even in the dark. Overall, PP/LMAl₂O₃ may function as a fundamental material in thermosensitive tactile sensors for lithology identification.