Research and manufacture of large-range and high-toughness conductive silicon rubber composite pressure sensor

Based on the piezoresistive effect of nano conductive rubber, conductive silicone rubber composite pressure sensor was prepared using the matrix material silicone rubber, nano superconductive carbon black, silk fiber fabric, interdigital electrode, buffer polymer material and encapsulation mold by processes such as internal mixing, open mixing, vulcanization and encapsulating, and the conductive silicone rubber composite material with the optimal piezoresistive characteristics was prepared by optimizing the content of conductive filler in the silicone rubber matrix. Finally, the application performance of encapsulated pressure sensor on bridge support model was explored. The results showed that when mass faction of nano superconductive carbon black ■ was 6.11%, the conductive silicone rubber composite material reached the penetration threshold point and had the best piezoresistive characteristics; the conductive sensing composite material obtained by implanting silk fiber fabric into conductive silicone rubber was then combined with the flexible interdigital single-layer electrode and encapsulated to generate the pressure sensor with increased range, sensitive detection, and enhanced toughness; the pressure sensor had a good linear relationship between the pressure signal and the electrical signal, and could achieve pressure detection within the range of 0 to 40 MPa. In addition, the measured value of the pressure sensor in the bridge support model test were highly consistent with the theoretical value.