Epoxy-silane: a non-removable film pretreatment for “Galvanneal”

Abstract

steel as corrosion protectors and adhesion promoters. Three concentrations of GPTE were tested. The silane coatings were characterized by cyclic voltammetry, linear polarization, electrochemical impedance spectroscopy and FESEM. The pretreatment that provided the best protection of the substrate was 20 % v/v GPTE solution. Pretreated panels were exposed in the 100 % humidity chamber and then painted using a water-based paint. Panels without pretreatment or unexposed were also painted. Painted panels were placed in the salt spray and in the humidity chambers. The presence of the silane does not modify the paint/substrate dry adhesion. The best results after exposure in the accelerated tests chambers were obtained with the painted panels pretreated with GPTE 20 % v/v, even those pretreated and exposed to the humidity chamber before painted had better resultsthan painted galvanneal without pretreatment.