Piezoresistive response to changes in contributive tunneling film network of carbon nanotube/silicone rubber composite under multi-load/unload

The piezoresistive effect of carbon nanotube filled silicone rubber composite under the multi-load/unload are studied. For the composites with the mass ratio of carbon nanotube to silicone rubber ranging from 0.04 to 0.10, the piezoresistivities are monotonically increasing within the pressure ranging from 0 to 1 MPa. The hysteresis (repeatability) error decreases with the increase of the number of the load/unload cycles. There exist the increasing and decreasing tendencies in the electrical resistance of the composite under the multi-load/unload, which are caused by the changes in the resistivity and the geometric size of the composite. The resistivity increases with the increase of the pressure. The absolute value of the deviation between the resistivities under the same pressure in the adjacent load (unload) cycles decreases with the increase of the number of the load (unload) cycles. The variations in the resistivity under the multi-load/unload are explained by analyzing the changes in the three-dimensional network composed of the contributive tunneling films (CTFs) between the adjacent carbon nanotubes.