Preparation of Graphene Thermally Responsive Double-Layer Composite Fibers via Dry Spinning for Wearable Intelligent Sensors

This article reports an innovative method for using flexible, extremely sensitive double-layer composite fibers in thermal response sensors. A double-layer fiber sensor with dual corresponding effects is prepared by assembling poly(methyl methacrylate) (PMMA) and graphene layers using dry spinning. The sensor achieves sensitive thermal deformation ability by utilizing the bimetallic sheet principle and the difference in thermal expansion performance between the two materials. The sensor can respond to light stimuli by doping the graphene layer with TiO2 and TiN. The reduced graphene oxide (rGO)/PMMA double-layer fiber thermal response sensor prepared by the chemical reduction of graphene has a fast response ability. When the relative temperature changes from 20 to 50 °C, the sensor response time averages within 2 s, and the bidirectional curvature change rate of the fiber material can reach a maximum of 300%. The sensor exhibits real-time, sensitive electrical performance changes under the stimulation of moisture or light temperature, demonstrating excellent stability and recyclability. Weaving double-layer fibers into two-dimensional (2D) fabrics and monitoring environmental temperature through changes in sensor deformation and electrical properties lays a solid theoretical foundation in thermal sensing and intelligent fabrics.