Raising polyester performance with TMCD glycol

 
Polyester polyols are one of the primary binders used in industrial and automotive coatings. They impart good appearance, adhesion and a better balance of hardness and flexibility at high solids. Chemical resistance and outdoor durability continue to be areas for improvement due to weak ester bonds along the polyol backbone. Polyesters containing NPG glycol (2,2-dimethyl-1,3-propanediol) have long been the industry standard for high-performance polyester coatings. Our work has shown that a combination of NPG and TMCD glycol (2,2,4,4-tetramethyl-1,3-cyclobutanediol) raises the overall performance of the coating to another level and can potentially open multiple areas of application. TMCD increases polyol glass transition temperature while maintaining excellent solvent solubility at high solids content. And these polyols exhibit a robust balance of hardness and flexibility with improved chemical resistance, hydrolytic stability and outdoor durability in both isocyanate- and melamine-crosslinked coatings. TMCD glycol has the potential to raise the durability and service life of polyesters used in industrial coatings, including auto OEM, auto refinish, coil, packaging, maintenance, machinery and equipment applications.