SYNTHESIS, CHARACTERIZATION AND APPLICATION OF POLYANILINE-ORGANOCLAY NANOCOMPOSITES

Abstract

ABSTRACTPolyaniline (PANI) - organoclay nanocomposites were prepared by intercalation of aniline monomer into montmorillonite (MMT) modified by polyoxyalkylene followed by subsequent oxidative polymerization of the aniline in the interlayer spacing. The organoclay was prepared by cation exchange process between sodium cation in MMT and NH3+ in four different types of polyoxyalkylene diamine and triamine with different molecular weight. Infrared spectra (IR) confirm the electrostatic interaction between the positively charged group (NH3+) and the negatively charged surface of MMT. The absence of d001 diffraction band in the nanocomposites was observed at certain types and contents of organoclay. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were employed to determine the dispersion of the clay into PANI. PANI chains in the nanocomposites are more thermally stable than pristine PANI. This improvement is attributed to the presence of nanolayers with high aspect ratio acting as barriers, thus shielding the diffusion of degraded PANI from the nanocomposites. The electrical conductivity of the nanocomposites was increased 30 times more than that of pure MMT at certain concentration. PANI-organoclay nanocomposites were used as curing agent for epoxy resins. IR and Differential Scanning Calorimetry (DSC) confirm the curing of epoxy. The absence of d001 diffraction band of organoclay in the nanocomposites was observed by X-ray diffraction (XRD). The structure argument was further supported by TEM. Electrical conductivity of the nanocomposites within the range 2.1X10-7 – 3.2X10-7 S/cm depending on the concentration of the PANI-organoclay.