| 초록 |
The piezoresistivity of polydimethylsiloxane(PDMS) composite with different copper content under different pressure ranges were studied. The experimental results showed the various the piezoresistive behavior. There was a critical pressure at which the electrical resistance decreases first and then increases. The critical pressure of composite with 25.3, 31.7, 38.0, 44.4, 50.7 vol% copper concentration were 0.19, 0.49, 0.75, 1.4 MPa, respectively. The gauge factor of the composite was then calculated from the data at different stress levels. When the composite strain was kept constant, both the electrical resistance and the stress decreased with time. After repeated pressure treatment, there was a decrease in the change of conducting structure due to the irreversible deformation of polymer matrix. The behaviors were explained by the tunneling conduction theory which provides a good approximation to the piezoresistive effect. |
