A novel catalyst of lanthanum tris(2,6-di-tert-butyl-4-methylphenolate) for ring-opening polymerization of adipic anhydride

Lanthanum tris(2,6-di-tert-butyl-4-methylphenolate) exhibits high catalytic activity toward the ring-opening polymerization of adipic anhydride. Poly(adipic anhydride) (PAA, M_n=1500) was obtained with a conversion of 86.0% within 1 h in methylene chloride at 20 °C. Three melting peaks were found in the DSC curve of the polymer at 51.4, 64.5 and 108.9 °C, respectively.