The bulk piezoresistive characteristics of carbon nanotube composites for strain sensing of structures.

The bulk piezoresistivity of carbon nanotube (CNT) in polymer matrix was discussed to develop a strain sensor for engineering applications. The polymer improves interfacial bonding between the nanotubes and the CNT composite and that enhances the strain transfer, repeatability, and linearity of the sensor. The largest contribution of piezoresistivity of the sensor may come from slippage of overlaying or bundled nanotubes in the matrix, from a macroscopic point of view.