Mechanism of Piezoresistive Effect of TiC-Polyvinyl ChlorideComposites

The behaviors of piezoresistivity in a new series of composite materials composed of TiC particles in polyvinyl chloride (PVC) insulating polymer are investigated. Experimental results show a Pronounced change in resistivity with pressure, making the composite materials attractive candidates for pressure or stress sensors with sensitivities much higher than the conventional semiconductive silicon materials. Piczoresistive effect of TiC-PVC composite is related to the difference in the elastic properties of the TiC particles and PVC polymer, and to the large changes in resistivity with concentration close to 25 vol%TiC in composite.