Preparation of Polypyrrole Nanocomposites with Organophilic and Hydrophilic Montmorillonite and Investigation of Their Corrosion Protection on Iron

The nanocomposite of polypyrrole with organonophilic montmorillonite and hydrophilic montmorillonite clays was prepared by in situ polymerization of pyrrole monomer in the presence of montmorillonite nanoclays. FTIR spectroscopy studies and X-ray diffraction pattern were used to confirm the formation of a polypyrrole/montmorillonite nanocomposite. The scanning electron microscopy image of the nanocomposite showed the homogeneous and continuous structure of the nanocomposite. Also cyclic voltammetry studies revealed that the synthesized nanocomposites were electroactive. The anticorrosive properties of nanocomposite coatings on iron coupons were evaluated and compared with pure polypyrrole coating. According to the results in corrosive environments, the polypyrrole/organonophilic montmorillonite nanocomposite has enhanced corrosion protection effect in comparison to pure polypyrrole and polypyrrole/hydrophilic montmorillonite coating. It was concluded that the better corrosion protection effect was due to the better dispersion of organophilic montmorillonite nanoclays in the polymer matrix, which results in a decrease in the corrosion current and corrosion rate. (C) 2013 Wiley Periodicals, Inc.