The principal types of epoxy resins that are used for corrosion-resistant
coatings are those based on the condensation of bisphenol A and epicholorohydrin.
In this case, the polyhydroxy bisphenol A is reacted in the presence of alkali,
with epichlorohydrin to form the basic epoxy resin.
The success of the epoxy coatings has been the result of the chemical reaction
of curing agents through the secondary hydroxyl group on the body of the epoxy
resins and the terminal epoxide groups.
The basic epoxy resins may be in the form of relatively low viscosity liquid
resins or they may be solid resins of increasing hardness, depending on the size
of the molecule.
both the liquid and the solid resin may be used to form corrosion- resistance
coatings, or a combination of both the liquid and solid epoxy resins can be
mixed into a coating in order to develop the reactivity necessary for the
particular material desired.