Patrick Salagnac

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.

Rheological properties of conductive polymer composite (CPC) filled with double percolated network of carbon nanoparticles and boron nitride powder

Abstract In this study, double percolated network of carbon nanoparticles and ceramics powder is used to uncouple electrical and thermal conductivity of polymer composite. The influence of ceramic powders on morphological properties of a biphasic conductive polymer composite (CPC) is investigated by means of rheological measurements. The biphasic materials studied are blends of a thermally conductive polymer phase (syndiotactic poly(styrene) (sPS) filled with boron nitride (BN)) with an electrically conductive polymer phase (high-density poly(ethylene) (hdPE) filled with nano-structured carbon black (NCB)) into a cocontinuous structure. The elastic modulus (with viscous modulus) was found to be the most sensitive rheological property to accurately detect the co-continuous morphology in our system. It was found to be at 40% v/v of hdPE-NCB, which can be interpreted as the phase inversion.

Electrothermal Behavior of Conductive Polymer Composite Heating Elements Filled with Ceramic Particles

In this study, the influence of ceramic powders on the electrical and thermal behavior of biphasic conductive polymer composites when subjected to electrical potential difference is investigated by means of experimental measurements and modeling. The biphasic materials studied are blends of a thermal conductive polymer phase (syndiotactic polystyrene filled with aluminum oxide or boron nitride) with an electrical conductive polymer phase (high-density polyethylene filled with carbon black) in a cocontinuous structure. The thermophysical characteristics of the biphasic materials were measured as a function of temperature. This thermophysical characterization showed that the thermal conductivity of conductive polymer composites is doubled when filled with a 20% volume of ceramic powder. 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 correlated well, which shows the relevance of adding aluminum oxide or boron nitride in the biphasic materials studied to enhance thermal conductivity of biphasic conductive polymer composites without modifying the electrical conductivity.