Inexpensive and readily available Ce₂O₃ and CeO₂ catalyzed ring-opening polymerization of lactone

Stable and inexpensive catalysts are particularly important in the catalysis industry. This study investigated cheap stable Ce₂O₃ and CeO₂ as catalysts for the ring-opening polymerization of rac-lactide (rac-LA) and ε-caprolactone (ε-CL). Both Ce₂O₃ and CeO₂ effectively catalyzed the polymerization of lactones. The catalytic efficiency of Ce₂O₃ was significantly higher than that of CeO₂. The catalytic polymerization process was carried out under controlled conditions, and narrow molecular-weight distributions of polylactide and polycaprolactone were obtained. A kinetic study of the catalytic polymerization of rac-LA showed that the polymerization conformed to first-order kinetics and was controllable.