Vanillin-Based Photocurable Anticorrosion Coatings Reinforced with Nanoclays

Abstract

This study investigates the chemical–physical properties and anticorrosion effectiveness of UV-cured coatings produced using epoxidized vanillin (DGEVA) as biobased precursor, then reinforced by the addition of nanoclay. After optimizing the UV-curing parameters of three different formulations by Fourier transform infrared spectroscopy (FTIR), the thermo-mechanical properties of the coatings are assessed by differential scanning calorimetric analysis (DSC), dynamic thermal mechanical analysis (DTMA), and pencil hardness. The coatings are applied on mild steel substrates and then their barrier properties are investigated by electrochemical impedance spectroscopy measurements, immersing the samples in 3.5 wt% NaCl aerated solutions. The results show the good corrosion protective effectiveness of the biobased coatings. The nanoclay addition has a beneficial effect, as it hinders the diffusion of the aggressive ions from the electrolyte solution to the metal substrate. The reported findings demonstrate the possibility of using biobased precursors and UV-curing technology to reduce the environmental impact of the coating industry.