Paints & Coatings Resource Center

Ask the Expert Question-and-Answer Archive

by Ron Joseph

April, 2008

Difference between ENAMEL and POLYURETHANE

Q: What is the difference between ENAMEL and POLYURETHANE? I would like to have a scientific explanation if possible.

Thanks in advance.

A: Typically we refer to high gloss, smooth decorative top coats as "enamels". Therefore, you can purchase epoxy enamels, polyurethane enamels, and most frequently, alkyd and/or acrylic enamels. When a painter uses the word "enamel" he is usually referring to a high gloss, smooth, decorative alkyd and/or acrylic top coat.

Polyurethanes do not need to be high gloss, smooth and/or decorative; therefore, they are usually only referred to as top coats, although painters might use the word "enamel" to describe them

A polyurethane can be a single or two-component coating. In the case of two-component coatings, the first component contains the colored pigments and most of the other ingredients. The resin of the first component is usually either a polyester or an acrylic. The second component in most cases comprises a clear polydiisocyanate resin, that is commonly called the curing agent. After the two components have been mixed, the resulting coating is called a polyurethane.

Good luck,

Ron Joseph

What's New | About PCRC | Compliance Assistance | Regulations | Technical Info | News | Homeowners | Search | Disclaimer | Home

©2012 Paints and Coatings Resource Center