Polyaniline precursor with surfactant–monomer function for the synthesis of graphite nanosheet/polyaniline composites

Anilinium dodecylbenzenesulfonate (S1) was used as the surfactant and monomer of conductive polyaniline in the synthesis of graphite nanosheet/polyaniline (GNS/PAni) composites. First, natural graphite was subjected to mechanical grinding in a planetary mill for 2, 7, or 12 h. The characterization of the grinding products, by X-ray and Raman spectroscopy, and electron microscopy indicated that the graphite structure degrades with increasing time. 7 h grinding was considered as an appropriate time, because of a significant increase in surface area with moderate degradation of the material. Subsequently, for the composite synthesis, the milled graphite was dispersed in the aqueous phase and sonicated in the presence of S1. The oxidative polymerization of S1 caused the increase in surface area with an increase in the content of S1. This increase was attributed to the amphiphilic character of S1, which allowed reducing reagglomeration of the milled graphite during S1 oxidative polymerization; measurements of surface area by BET supported this result. The morphology of the PAni deposits on GNS, determined by electron microscopy, regarding the pure polyaniline obtained under equivalent conditions, showed that S1 adsorbed onto the GNS and subsequently, polymerized on the surface thereof, demonstrating the reactive character of S1.