ISOCYANATES FOR COATINGS APPLICATIONS

The article describes the chemistry of polyisocyanates for coatings applications starting from the basic principles and reactions in polyurethane (PUR) chemistry. The derivatization of diisocyanates to polyisocyanates with low residual monomer content suitable for coatings is discussed. Curing of the two component systems lead to PUR coatings with the known outstanding performance due to urethane linkages and intermolecular hydrogen bonding resulting in high chemical resistance and durability of the final film. Adjustment of components - polyisocyanates as well as polyols as reaction partners - is the basis of new developments of so called self healing PUR systems for coatings applications. Modern, very high solids' coatings containing more than 90% non volatile components as well as hydrophilically modified hardeners for waterborne systems are the basis of highly efficient coatings and improvement of the ecological profile of the whole technology of surface protection.