ViaCat dibutyltin and monobutyltin compounds are used as esterification catalysts for the manufacture of organic esters and/or polyesters. Examples of simple organic esters include plasticizers, lubricants and heat-transfer fluids.
Polyesters produced by the use of organotin compounds are used as binders for formulating coatings for industrial use, or when modified with fatty acids they are used as binders for air drying coatings for decorative and protective applications. Dibutyltin compounds are also used as catalysts for transesterification and polycondensation of dimethyl terephthalate into polyethylene terephthalate or manufacturing of high molecular weight copolyester elastomers.
The use of these materials is either in packaging applications or engineering plastics. The esterification reactions catalyzed by ViaCat organotin compounds require temperatures above 200°C, which is much higher than those involving strong acid catalysts, such as p-toluenesulfonic acid. Though, number of advantages justify the use of organotin catalysts. The side reactions are minimized so the end products have better color and odor properties because fewer by-products are formed, there is no need for refining to remove the catalyst residues and the equipment corrosion is eliminated. Usual levels of tin catalysts are 0.05–0.3 wt % based on the total reactants charged.