Prediction of filler/matrix interphase effects on AC and DC electrical properties of carbon reinforced polymer composites

Abstract

This study predicts the effect of the conducting filler/ insulating matrix interphase on the electrical properties of two series of percolated systems, differing from the type of carbon black particles mixed in an aminecured epoxy matrix, diglycidylic ether of bisphenol F. To take into account the interactions between the conducting filler and the matrix, as well as filler-filler overlapping, we introduce three parameters, characteristic of the interphase zone, such as concentration, conductivity and volume, on the generalized effective medium (GEM) model for DC and AC electrical conductivities. These interphase parameters, characterizing the boundary of the shaded zone between the macromolecular chain and the conducting particles, depend on the filler type and concentration. One output of GEM-modified model is that it provides a mean to estimate the volume, concentration and intrinsic conductivity of the interphase in a composite by fitting the experimental data over a broad range of frequency.

Electrical properties of melt-mixed polypropylene and as-grown carbon nanofiber composites: Analysis of their interphase via the AC conductivity modeling

“…This deviation of s and t can be caused by the fact that the GEM does not take into account important parameters, such as the particle geometry, 49 existence of aggregates, 50 and interphase region between the CNFs and PP matrix, 51 which should play an important role in the final properties of the PP/CNF composites. Therefore, a modified GEM, which includes the volume fraction (ϕ int ) and the complex conductivity of the interphase (σ int ), is proposed in this study 20 which it simplifies towhere ϕ int depends strongly on the filler concentration ϕ and on the critical parameter k given by Todd and Vo 52,53 as…”

“…54 In this regard, comparable behaviors of f int and k with frequency, calculated by this modified GEM, were reported for carbon black-loaded epoxy composites. 20…”

“…19 In the present work, the AC electrical conductivity at room temperature of the same type of PP/CNF composites is used to test the validity of the GEM model. Moreover, the potential of a modified GEM 20 that takes into consideration the effect of the interphase between the CNFs and the PP is also examined. It is observed that the modified GEM presents a good agreement with the experimental measurements, from which the values of the volume concentration and complex electrical conductivity corresponding to the interphase of the PP/CNF composites could be estimated over the range of frequency analyzed.…”

Development of heating elements based on conductive polymer composites for electrofusion welding of plastics

“…There are many studies in which various aspects of the influence of the conductive filler concentration, the nature of polymer, the distribution of filler in the volume of the polymer matrix, interaction between polymer and filler on the electrical properties of polymer composites have been studied. 29,30 In general, the filler content determines the level of conductivity in the composite and the electrical behavior of the composite under the influence of various factors (the value of the applied voltage, temperature, and deformation forces, etc.). Carbon black is…”