Isocyanatoorganosilanes – Chemistry and Process Technology

Isocyanatoorganosilanes, commonly used in industrial settings as adhesion promoters between organic polymers and inorganic materials, are of great commercial interest in the coatings, adhesives and sealants markets. Isocyanatosilanes can be made through three different routes:  1) corresponding carbamatosilane thermal cracking with loss of methanol, 2) phosgenation of a corresponding aminosilane or 3) reaction of a chloropropylsilane with cyanate salts. Commercial isocyanatoorganosilanes are primarily made via thermal cracking of corresponding carbamatoorganosilanes. Other routes have not been commercialized due to either safety issues or economical inefficiency. The advantages and disadvantages of these routes, as well as a patent literature review, will be discussed.