Thermal Stability of Electrical Properties and Amine Vapour Sensitivity of In-Situ Prepared Polyaniline/Graphene Nanocomposites Assisted by Sodium Dodecyl Sulfate Micelles

Polyaniline (Pani)/graphene (GN) nanocomposites were prepared by in-situ oxidative polymerization of aniline with GN in presence of sodium dodecyl sulfate. The effects of polymerization and modification of the chemical structures in the nanocomposites were characterized by fourier-transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FE-SEM) and X-ray diffraction techniques (XRD). Sodium dodecyl sulfate played the role of a surfactant, improving the dispersion of GN within the polymer matrix simultaneously. FTIR results revealed the presence of π-π interactions between Pani and GN leading to the formation of a charge-transfer complex. The thermal stabilities of the electric properties of the as-prepared nanocomposites were investigated as a function of GN content. As-prepared Pani/GN nanocomposites showed greater electrical conductivity as well as improved thermal stability in terms of DC electrical conductivity retention under isothermal and cyclic ageing conditions compared with pure Pani. They were also observed to possess better amine sensing properties in comparison to pure Pani when exposed to the vapour of methylamine.