Synthesis of Organotin Catalysts for the Polymerization of Lactide

Abstract

Organotin and organoaluminum catalysts have both been proven to be good catalysts of polylactide, a biodegradable polymer. However, organotin catalysts do not catalyze the ring opening polymerization of lactide quickly enough to be used for most industrial applications. For this reason, organotin catalysts are currently used. However, organotin catalysts catalyze the transesterification of polylactide as well as the polymerization. Two classes of alkyltin chloroacetate complexes were synthesized and tested for catalytic and transesterificative ability. The first class of complexes was dialkyltin bischloroacetates, and the second class was trialkyltin monochloroacetates. Both classes proved to be catalytic toward the polymerization of lactide, as well as toward transesterification. The trialkyltin monochloroacetates proved to be quicker catalysts as well as causing less transesterification.