Ring-opening polymerization of 2,2-dimethyltrimethylene carbonate (DTC) has been carried out by using single component rare earth tris(4-tert-butylphenolate)s (Ln(OTBP)(3)) initiators for the first time. The influences of rare earth element, solvent, temperature, monomer and initiator concentration as well as reaction time on the polymerization were investigated. The kinetics indicates that the polymerization rate is first order with respect to monomer concentration and initiator concentration, respectively. The overall activation energy of the ring-opening polymerization amounts to 78.7 kJ/mol. Some living character of the reaction was confirmed by adding another portion of DTC monomer into an almost completely polymerized system. PDTC was characterized by H-1 NMR, GPC, IR and DSC. PDTC obtained has no ether unit which resulted from CO, elimination. DSC data identified two crystalline modifications and showed some influences of molecular weight on the melting point and melting enthalpy. Mechanism studies showed that monomer inserted into the growing chains with the acyl-oxygen bond scission rather than the break of alkyl-oxygen bond. (C) 2003 Elsevier B.V. All rights reserved.