The ring-opening polymerization of 2,2-dimethyltrimethylene carbonate (DTC) catalyzed with imidazol-2-ylidenes substituted by benzyl, isopropyl, and methyl was conducted. The influences of substitutional group, monomer, catalyst, and initiator (benzyl alcohol) concentration, as well as polymerization temperature and reaction time were investigated in detail. The kinetics studies indicate that the polymerization rate is first-order with respect to both monomer and catalyst concentrations. The overall activation energy amounts to 51.06 kJ/mol. Mechanistic studies reveal that the 2,2-DTC polymerization proceeds according to a monomer-activated process.