Epoxy Paints

Q. I am the vice president of manufacturing for my company. Managers at oone of our plants want to upgrade their paint finish to achieve better product durability. I am conducting an engineering study on the applicability of an epoxy system. During a recent staff meeting about this subject, suggestions were made about using an epoxy or an epoxy polyamide.

What is the difference between an epoxy and epoxy-polyamide cured system? Someone said, “it’s the curing agent.” Which one is better.? W. F.

 

A. All epoxy paints are not created equal. However, they all do contain epoxy resin in some form or another. Without going too deeply into the chemistry of these materials, there are basically two types of epoxy paints produced: single--package and two- component. Single-package epoxy paints contain epoxy ester resins, and they are self curing by air drying or baking. On the other hand, two-component epoxy paints contain epoxy resins cured using alcohols, amines, anhydrides, carboxylic acids, phenolics, and polyamides. In general, the two-component epoxy paints have better performance characteristics than single-package materials.

It is important to remember that two-component epoxy paints require special handling because they have a finite pot life. Pot life is the amount of time it takes a batch of catalyzed paint to gel after mixing. Your engineering study may show that it is more convenient to apply them using multi-component spray equipment.