Polyaniline: A novel bridge to reduce the fire hazards of epoxy composites

As a graphene-like two dimensional nanomaterial, MoS2 had been considered as promising nanofillers for fabrication of polymer-based materials with high performances. However, its dispersion and functionalization represented a critical challenge. In present work, polyaniline (PANI) coating was successfully grown on the surface of exfoliated MoS2 nanosheets by in situ polymerization method in order to improve the dispersion quality and interfacial interactions between MoS2 and polymer matrix. The obtained PANI-MoS2 hybrids were characterized through XRD, Raman spectrum, FTIR, TGA, XPS, TEM and further introduced into epoxy matrix. It was clearly observed that the addition of a PANI coating not only improved the dispersion of MoS2 in the matrix and the interfacial bonding between MoS2 and epoxy, but also obviously reduced the fire hazards of epoxy. By adding 2 wt% PANI-MoS2, the peak heat release rate and total heat release values of epoxy composites were remarkably reduced by 49% and 22%, respectively, in comparison with those of neat epoxy. In addition, the amount of smoke produced and toxic CO released was inhibited obviously. The well dispersion, labyrinth barrier effect, catalytic charring effect of PANI-MoS2 hybrids and combination effect between PANI and MoS2 were believed to the primary source for the remarkable improvement of fire safety.