By Denis Heymans and Catherine Romanowska, Hexion Research Belgium; and Marcelo Herszenhaut, Hexion Inc.

Two-component polyurethane systems (2K PU) are the most widely used topcoats for high-quality protective applications, combining outstanding chemical and weathering resistance with excellent mechanical properties. However, environmental, market and cost pressures have led to the development of alternatives to these conventional topcoats, including isocyanate-free binders. This article presents a new family of polymers, combining neoacid esters and alkoxysilane monomers and compares them to 2K polyurethane and acrylic silane systems for typical performance parameters....