Polyester-graphene primer coatings: corrosive and mechanical properties

Abstract

This study developed and characterized of the polyester (PE)-graphene (GR) primer coating in corrosion resistance and mechanical properties. PE coatings varied with 0-8% of GR were prepared using ultrasonication method and undergone the morphology characterization using Field Emission Scanning Electron Microscopy (FE-SEM), and also being evaluated using various corrosion and mechanical tests, namely tafel test, immersion test, adhesion test and hardness test. The FE- SEM analysis shows that the homogeneous dispersion of GR in PE resin at 2% of GR loading, whilst at higher loading of GR produced agglomeration that reduced the corrosion inhibition properties of the coatings. The corrosive properties were characterized using autolab potentiostat for determination of corrosion rate and immersion testing using 3.5% NaCl for 9 days. The results show that the optimum corrosion rate of coatings was found at 2% of GR loadings which is 0.586 mmpy. This is due to at 2% GR is optimum as a physical barrier and inhibit the diffusion pathways of corrosive species as there is no agglomeration of GR which is showed that very well dispersion of GR in the PE resin. Whilst, immersion observation also shows the optimum condition at 2% of GR loading, which has a lower corrosion property. On the other hand, adhesion and hardness testing were enhanced by increasing of GR loadings (0-8%) as the properties of GR imparted high strength, rigidity, and durability. Therefore, the incorporation of GR is very efficient materials to enhance both mechanical and corrosive properties of polymeric coatings.