Simulation of electrical and thermal behavior of conductive polymer composites heating elements

Experimental and modeling studies were performed to describe the electrical and thermal behavior of two diphasic conductive polymer composites when subjected to electrical potential difference. The evolution of effective thermal conductivity of the conductive phase, poly(ethylene-co-ethyl acrylate)-carbon black or poly(amide12-b-tetramethyleneglycol)-carbon black, have been measured and compared to existing empirical models as a function of filler content. The diphasic materials were obtained by blending a conductive phase with an insulating polymer, poly(butylene terephthalate). The thermophysical characteristics of the diphasic materials were measured as a function of temperature. Ohmic heating experiments were performed on extruded tapes. A two-dimensional finite element model has been developed to determine the thermal and electrical behavior of these devices. The numerical and experimental results were in good agreement. This original use of diphasic material shows their interest in achieving heating elements.