Highly Filled Glycerol/Graphite Suspensions as Fluidic Soft Sensors and Their Responsive Mechanism to Shear

Abstract The conductive suspensions composed of high content of graphite flakes dispersed in glycerol demonstrate flow field sensitive resistance and memory effect of the deformation history, which are expected to work as new fluidic soft sensors. The resistance of the suspensions responds to the local flow field caused by vibrations, stretching, and shear. The combined electro‐rheo tests are carried out to reveal the resistance response to different types of flow field. Based on the variations of resistance, a microstructural model considering the direction of the flow field and the corresponding transition kinetics of the different microstructures of fillers are established in the present work. The contents of the microstructures vary with both the shear strain and the shear direction and the transition rate between the different microstructures depended on the shear rate. The unveiled mechanism via the proposed model is expected to deepen the understanding of conductive suspensions so as to further guide the design of soft sensors based on conductive suspensions and composites.