Investigation of piezo-capacitance and piezo-resistance properties of solid silicone rubber-conductive carbon black composites

Flexible electronics have created demand for stretchable materials that can be used for various electromechanical transduction. These applications involve tactile sensing, where piezo-capacitance and piezo-resistance mechanisms are utilised for response of materials to external stimuli. The present study deals with the investigation of the above properties for solid silicone rubber-conducting carbon black composites fabricated from compression moulding process. Effect of various factors such as conductive filler and curing agent loading, mixing time and curing temperature on the response are evaluated using Taguchi analysis for achieving optimum response. The optimum piezo-capacitive and piezo-resistive sensitivities of 31.66 pF/MPa and 2.73 (MPa)⁻¹ are achieved for factor settings of lower values of conductive filler, curing agent loading and higher values for mixing time and curing temperature.