Understanding the role of silane pretreatments in an organic coating system. Part 1: corrosion performance and interfacial property

This work aimed at understanding the role of silane pretreatment layer in an organic coating system. The study consists of two parts. In the first part, the anticorrosion performance and interfacial property of silane-pretreated epoxy coatings were studied. The results showed that pretreatment with functional 3-glycidoxypropyl-trimethoxysilane (GPTMS) strongly improves the adhesion of epoxy-coated AA2024-T3 aluminum alloy due to the high interfacial compatibility between silane and epoxy coatings and that pretreatment with nonfunctional bis-1,2-[triethoxysilyl]ethane (BTSE) remarkably reduces the adhesion to the alloy because of low compatibility. Nevertheless, the BTSE film provides higher resistance to corrosion than the GPTMS-pretreated coating system, because the former is more hydrophobic and thicker.