Abstract
UDC 66.0
In this study, intercalated polypyrrole/montmorillonite nanocomposite was synthesized by a facile and simple solution intercalation method. The method is based on the exchanging of pyrrole monomers with sodium interlayer cations followed by polymerization by adding ammonium persulfate as oxidant. To avoid the spontaneous polymerization of pyrrole outside the clay, the proportions of pyrrole to clay and that of monomer to oxidant were varied. Several techniques have been used to study the structure and conductivity of the obtained materials: Fourier transform infrared spectroscopy, X-ray diffraction, Energy-dispersive X-ray spectroscopy analysis, scanning electron microscopy, Brunaner-Emmet-Teller technique, impedance spectroscopy and ultraviolet–visible spectroscopy. It was shown that it is not necessary to subject clay to organophilation with quaternary alkylammonium or to ultrasonic activation, or to treat it thermally to form intercalated nanocomposite. By increasing the amount of clay to that pyrrole, an intercalated polypyrrole clay nanocomposite is formed. The evidence of the intercalation of polypyrrole is deduced from the X-ray diffraction and the Brunaner-Emmet-Teller technique specific surface. Both the expansion of the basal interlayer distance to 14 Å and the decrease of the specific surface area from 78.2 for the clay to 48 m2×g-1 prove the formation of an intercalated structure. The conductivity has been measured using impedance spectroscopy. The dc conductivity was in the range of 2–10-3 S/cm.
Keywords: nanocomposite, microcomposite, polypyrrole, montmorillonite, intercalation, conductivity.