Preparation of polypyrrole (PPy)-derived polymer/ZrO2 nanocomposites: Effects of nanoparticles interface and polymer structure

New polypyrrole (PPy)-derived polymer/ZrO2 nanocomposite materials are prepared by single-step oxidative polymerization of pyrrole (Py) and/or N-methylpyrrole (mPy) in the presence of HCl-functionalized ZrO2 nanoparticles and ammonium persulfate. The physicochemical features of the PPy-ZrO2, poly(Py-co-mPy)-ZrO2 and PmPy-ZrO2 hybrids were analyzed by XPS, FTIR, XRD and UV-Vis techniques. To explore the advantages of these nanocomposites for potential applications, their thermal, conductive and electrochemical properties were investigated. The characterization reveals that a chemical bonding, based on electrostatic interactions, is established between the polymers and the ZrO2 nanoparticles. Interestingly, it is found that the growth of polymer on the surface of Cl-functionalized ZrO2 becomes more significant as the Py moiety (-NH- species) content in the polymer increases. The thermal stability and conductivity of the polymers increase by hybridization with the ZrO2 nanoparticles. This is assigned to the affective interaction of the polymers with the ZrO2 nanoparticles. Particularly, the resulting nanocomposites keep high conductivities, ranging between 0.323 and 0.929Scm(-1). Finally, voltammetric characterization shows that the PPy-ZrO2 and poly(Py-co-mPy)-ZrO2 nanocomposites are electroactive, thus demonstrating their capability for electrochemical applications. These results highlight the great influence of the nanoparticle interface and the nature of monomer on the nanocomposite formation and properties.