Figures of merit for electrically conductive polymer composites

In an effort to determine the optimal balance of electrical and mechanical performance for electrically conductive polymer composites, three figures of merit were evaluated. All three figures of merit displayed peaks and/or discontinuities at a particular filler loading. These loadings appear to correspond to the critical pigment volume concentration for a given system. Composite systems based upon latex as the matrix starting material showed peaks in the figures of merit at very low carbon black concentrations (10 vol%), while composites prepared with polymer solutions or melts had peaks above 20 vol% carbon black. These differences in behaviour are attributed to differences in microstructural evolution that occur with filler loading.