PIEZORESISTIVITY OF A SHORT FIBER ELASTOMER MATRIX COMPOSITE/

If the electrical resistance of a material depends upon external strai ning, the material exhibits 'piezoresistivity'. The piezoresistive beh avior has been realized in an electrically conductive elastomer compos ite where the microstructure of conductive fillers can be changed unde r finite deformation of elastomer, resulting in the change of the comp osite resistivity. In this paper, we analyze the piezoresistive behavi or of a conductive short fiber/elastomer matrix composite by applying a percolation model. Fiber reorientation model is applied to the compo site system with the aim of predicting the relation between the applie d finite strain and the reorientation of conductive short fibers. It i s found that the piezoresistive behavior of a conductive short fiber/e lastomer composite is attributed to the degeneration of initially perc olating network under the finite strain. Some numerical results are th en compared with our previous experimental data, showing a reasonably good agreement. (C) 1998 Elsevier Science Ltd. All rights reserved.