Preliminary Research On Resistance Relaxation For Carbon Black/Silicone Rubber Pressure-Sensitive Composites

Carbon black/polymer composites is a new type of flexible pressure-sensitive conductive composite materials, has a good mechanical and electrical properties, good flexibility characteristics. Because of silicon rubber is used as matrix of the pressure-sensitive composite materials, its performance will inevitably influenced by bulk materials. The resistance of pressure-sensitive composite materials in constant stress(strain) appears the time dependence, seriously affect the sensor precision.The main experimental content as follows:(1) Expounds the preparation methods of carbon black silicone conductive polymer composites, using microcosmic structure analysis method to analysis composite material for internal microstructure. Explore conductive composite micro-cosmic morphology.(2) Based on the key analysis about the seepage curve fitting to explore the conductive composite conductive mechanism, and to get its percolation threshold, on subsequent resistance relaxation experiments to provide institute of carbon concentration guidance.(3) Based on the analysis of the conductive theory of pressure sensitive conductive composite relaxation repetitive experiments, we find the influence that carbon concentration, loading speed, stress and other factors on the resistance relaxation, stress relaxation and stress-resistance relations.(4) Through the experiments analysis to find the resistance, stress along with time change rules in the relaxation experiments loading process, loading constant strain process and constant strain process.This research results provide a pressure-sensitive composite materials conductivity, seepage characteristic and resistance time dependence of the theoretical and experimental basis, and provides technical foundation to the developed of the flexible pressure sensor.