Fabrication and percolation behaviour of novel porous conductive polyblends of polyaniline and poly(methyl methacrylate)

The conductive polymer polyaniline is blended with conventional industrial thermoplastics in order to obtain an electrically conductive polymer blend with adequate mechanical properties. Processing these polyblends into foams yields a porous conductive material that exhibits immense application potential such as dynamic separation media and low-density electrostatic discharge protection. In the current study, the morphology of a thermally processable blend consisting of an electrically conductive polyaniline-dodecylbenzene sulfonic acid complex and poly(methyl methacrylate) is explored using a two-phase batch foaming setup. The effect of blend composition and processing parameters on the resulting porous morphology is investigated. The impact of the underlying microstructure and blend composition on the frequency dependent electrical conductivity is elucidated using multiple linear regression and a model is proposed. Finally, dielectric analysis is utilized to experimentally identify the critical dispersion frequency of an unfoamed blend composition near the percolation threshold. (c) 2010 Elsevier B.V. All rights reserved.