Polymerization of D,L-lactide in the presence of biocompatible catalyst bismuth subsalicylate

Abstract

Polymerization of D,L-lactide was performed in bulk at 160°C in the presence of bismuth (III) subsalicylate catalyst. Kinetics of the reaction was studied by differential scanning calorimetry in isothermal mode at 160°C and catalyst concentrations of 2500, 5000, and 7500 ppm. It was shown that the catalyst has a high activity: under this conditions an equilibrium conversion of 96% was achieved in 20–30 min, and the molecular weight of the resulting poly(D,L-lactide) reached 118 kDa.