Spectroscopic characterization of polyaniline formed in the presence of montmorillonite clay

This work shows the spectroscopic characterization of polyaniline–montmorillonite clay (PANI–MMT) composites prepared by polymerization of aniline in aqueous suspensions of montmorillonite clay and camphorsulfonic acid containing persulfate ions as oxidizing agent. X-ray diffraction, scanning electron microscopy, and X-ray absorption near Silicon K-edge data show that morphologies and structures of PANI–MMT nanocomposites depend on their relative amount. The electrical conductivity values of composites increase from 10−4 to 10−1 S/cm−1 when PANI–MMT ratio increases, and percolation threshold is observed when polymer/clay mass ratio is changed. Resonance Raman, UV–VIS–NIR spectroscopy, electron spin resonance (EPR) and X-ray absorption near Nitrogen K-edge data confirm that PANI has emeraldine salt form for all PANI–MMT materials prepared.