Flexible Conductive Substrate Incorporating a Submicrometer Co-continuous Polyaniline Phase within Polyethylene by Controlled Crazing

A polyethylene film with an incorporated nanodispersed polyaniline conductive network was developed by controlled crazing in a high-pressure reactor while immersed in an emulsified medium of aniline in chloroform. The resulting conductive material exhibited an average through-plane electron conductivity of 2 × 10–2 S·cm–1, within an order of magnitude of brittle doped polyaniline (1.2 × 10–1 S·cm–1), yet retained the ductility of the polyethylene matrix. It was also shown that 90% of the original conductivity was retained after 1% elongation. Embedded polyaniline fibers acted both as a nucleating agent to reduce the size of crystallites for controlled crazing and as submicrometer conductive nodes, connecting neighboring conductive conduits formed inside the crazing voids, with both effects contributing to the increasing electrical permeability of the secondary phase. For comparison, montmorillonite and TiO2 particles were tested as alternative nucleating agents to verify the effect of the preliminary embedded polyaniline fibers on the matrix morphology and, consequently, the conductivity acquired.