Synthesis and properties of PANI/SiO2 organic–inorganic hybrid films

PANI/SiO2 organic–inorganic hybrid films were prepared directly from polyaniline (PANI) emulsion solution and tetraethyl orthosilicate (TEOS) by sol–gel process. The evolution of phase, morphology and corrosion resistance ability of PANI/SiO2 hybrid materials were characterized by TG, FTIR, SEM and potentiodynamic polarization analysis. It was demonstrated that PANI/SiO2 organic–inorganic hybrid films have a homogeneous and smooth surface without detectable cracks. Potentiodynamic polarization analysis revealed that the hybrid films provided an exceptional barrier and corrosion protection in comparison with untreated aluminum alloy substrates. However, the increase of TEOS content in PANI/SiO2 organic–inorganic hybrid materials tends to exhibit brittleness and micro-cracks which will lead to the deterioration of corrosion resistance ability.