Polyaniline/polyvinyl chloride coatings for enhanced corrosion protection of the AA-7075-T6 alloy

Aluminum alloys are susceptible to pitting corrosion because ofthe presence of intermetallics compounds such asiron and copper[1]. Thus, as alternativeto overcomethisdrawback,polyaniline (PANI)hasbeenappliedas protective coatingon aluminum alloys. PANI is useddue toitsredox properties, which provide good anticorrosive properties,combined toits low cost andeaseof synthesis[2]. Nevertheless, PANI coatings show pores andother defects that affectsits protective property[3]. In this work, polyvinyl chloride (PVC) was used as filler for PANI’s poresand thecomparative study of the behavior of PANI and PANI/PVC system revealed that the blends offer higher corrosion protection than neat PANI coatings.The morphological structure of the blends was also evaluated by scanning electron microscopy (SEM), atomic force microscopy (AFM) and profilometry.Figure 1a shows that the coatings obtained from the blendshave significant high polarization resistance for electrodes coatedwith800 μLand 1000 μL of PANI/PVC solution. A similar corrosion protection behavior was observed from the linear polarization curves displayed in Figure 1b. Therefore, PANI/PVC coatings have great potential as anticorrosive coatings for protection of aluminum alloys.