Preparation of organic-inorganic bio-based epoxy coatings with high anti-corrosive performance

Epoxies derived from natural sources as an alternative to conventional petroleum-based epoxy resins have been used in sustainable coating applications. This study aims to create corrosion-resistant bio-based epoxy nanocoatings in the context of sustainable development. For this purpose, vegetable oil-based epoxy resins from cardanol and soybean oil were prepared. The structure of bio-based epoxies was confirmed by FTIR and 1H-NMR spectroscopy techniques. The epoxy functional silane precursor is synthesized from tetraethyl orthosilicate and (3-Glycidyloxypropyltrimethoxysilane by means of the sol-gel method. Amine curing agent and inorganic silica skeletons as polyhedral oligomeric silsesquioxanes and sol-gel precursor were added to the epoxy adduct and then cured. The curing kinetics of the formulations was followed by a differential scanning calorimeter. The chemical, mechanical, thermal, and anti-corrosive properties of the prepared coatings were investigated using various tests. The sustainable epoxy-based nanocoatings exhibited higher mechanical and thermal stability. In addition, the nanocoatings showed excellent corrosion resistance without the use of any anti-corrosive agent. The prepared green sustainable coatings will provide a more sustainable way to prepare bio-based coatings.