An aqueous composition is provided comprising a resin, a curative, a filler, a surfactant, and water; wherein the resin comprises an average molecular weight of less than about 800 Daltons and comprises at least 50 weight percent of at least one of: (a) an unmodified epoxy or phenoxy resin, or (b) a surfactant-modified epoxy or phenoxy resin. This composition, applied to a substrate and dried, can then be cured so as to thermoset the resin and self-assemble to form continuous pathways of filler within the resin matrix.