The nonisothermal cold-crystallization kinetics and subsequent melting behavior of poly(trimethylene terephthalate) (PTT) were investigated with differential scanning calorimetry. The Avrami, Tobin, and Ozawa equations were applied to describe the kinetics of the crystallization process. Both the Avrami and Tobin crystallization rate parameters increased with the heating rate. The Ozawa crystallization rate increased with the temperature. The ability of PTT to crystallize from the glassy state at a unit heating rate was determined with Ziabicki's kinetic crystallizability index, which was found to be about 0.89. The effective energy barrier describing the nonisothermal cold-crystallization process of PTT was estimated by the differential isoconversional method of Friedman and was found to range between about 114.5 and 158.8 kJ mol(-1). In its subsequent melting, PTT exhibited double-melting behavior for heating rates lower than or equal to 10 C min(-1) and single-melting behavior for heating rates greater than or equal to 12.5 degreesC min(-1). (C) 2004 Wiley Periodicals, Inc.