A newly developed polymer system is described that has the unique property of expanding when converted from the liquid (uncured) to the solid (cured) state Coatings on steel made from this class of materials should be desirable because the polymer to metal bond is intimate and would resist attack by salt spray and other corrosive agents. Described is a program to formulate coatings, apply them to steel specimens, and evaluate them side by side with state-of-the-art coatings.