Electrically conductive nanocomposites of aromatic polydisulfide/expanded graphite

Expanded graphite (EG) with different expansion ratios were prepared by the exfoliation of expandable graphite under microwave irradiation. Nanocomposite precursor was fabricated by direct solution blending of cyclic (arylene disulfide) oligomers with the EG fillers. Subsequently, the nanocomposite precursor was hot-molded at 200 degrees C to carry out simultaneously the in situ ring-opening polymerization (ROP) of these oligomers via free radical mechanism to prepare aromatic polydisulfide/EG nanocomposites. The resulting aromatic polydisulfide/EG nanocomposite exhibited a completely intercalated nanostructure as evidenced by TEM observation. Highly electrical conductivity of the composite was measured by a four-point probe resistivity determiner. Three-point bending tests were used to determine the flexural strength of the composites. The nanocomposite can be used as potential materials to prepare bipolar plate of polymer electrolyte membrane fuel cell due to its high electrical conductivity, recyclable properties of the matrix and nanoscale effect in gas barrier performance. (c) 2006 Elsevier Ltd. All rights reserved.