Correlation between current–voltage (I–V) characteristic in the electric–thermal equilibrium state and resistivity‐temperature behavior of electro‐conductive silicone rubber

In the electric–thermal equilibrium state the current–voltage (I–V) characteristics of conductive silicone rubbers above the percolation threshold are found to be nonlinear. A mathematic model as I = a 1 U ± ( a 2 U 2 + C ) has been built for the nonlinear I–V relations. Constant C and quadratic term a 2 U 2 can be considered as deviation from Ohm's law. For the first time, a correlation is found for conductive silicone rubber between the I–V characteristic in the electric–thermal equilibrium state and the resistivity–temperature characteristic. Samples with positive temperature coefficient (PTC) resistivity effect exhibit negative deviation from linearity, with an I–V relation as I = a 1 U − ( a 2 U 2 + C ). Samples with negative temperature coefficient (NTC) resistivity effect exhibit positive deviation, with an I–V relation as I = a 1 U + ( a 2 U 2 + C ). The higher the loaded voltage, the more pronounced the deviation. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008