Polyaniline/clay nanocomposites. A comparative approach on the doping acid and the clay spacing technique

Polyaniline/clay nanocomposites (PCNs) have been synthesized by oxidative polymerization of aniline by using two different clay treatment techniques (mechanical agitation and ultrasonication), as well as two different doping acids (hydrochloric acid - HCl - and dodecylbenzene sulfonic acid - DBSA -). The effect of both conditions on their chemical nature, structure and morphology has been studied by Raman spectroscopy, X-ray Diffraction (DRX), Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM). PCNs electrical conductivity was measured by the 4-probe technique. The results reveal that the type of clay treatment shows no impact on the PCNs morphology, but it does determine their final structure - either intercalation or exfoliation - which has a remarkable effect on the electrical conductivity. Moreover, the doping add presented a strong influence on both morphology and electrical conductivity of the prepared PCNs. In this work, HCl doping and ultrasonication are highlighted as the optimal PCN synthesis conditions, since the highest electrical conductivity is reached with less time and energy consumption.