New anticorrosive primer based on modified poly(ester-amide) and alkyd resins with 4-(N,N-dimethylamino) benzylidene glutamic acid for steel protection

Purpose This study aims to present the preparation of new paint formulations based on oil-based polymers, such as modified poly(ester-amide) (PEA) and alkyd resins, for steel protection. Design/methodology/approach New modified PEA and alkyd compositions were synthesized using a dicarboxylic acid source, following the authors’ previous work. The resins were evaluated as binders in primer formulations. Coatings (105 ± 5 µm thickness) were brush-applied on mild steel panels and tested per international ASTM standards for physico-mechanical properties, chemical resistance and corrosion performance. Findings The tests revealed that when the modified PEA and alkyd resins were incorporated into primer formulations, corrosion resistance, physico-mechanical properties and chemical resistance were all enhanced. Originality/value Modified PEA and alkyd resins are cheaper and can be used to replace other, more expensive binders. The main advantage of these binders is that they combine the properties of both polyester and polyamide resins based on nitrogenous compounds.