In this article, kinetics of neat poly(lactic acid) (PLA) and its blends with triphenyl phosphate (TPP) and/or talc crystallized isothermally in the temperature range of 113-128 degrees C was analyzed by differential scanning calorimetry (DSC) and described by the Avrami equation. The results showed that the average value of Avrami exponents n is around 2.0 for neat PLA and the PLA/15TPP blend, and around 3.0 for the PLA/1.2Talc blend and the PLA/15TPP/1.2Talc blend. The crystallization rate constants k for neat PLA and its blends were increased in the following order: the PLA/15TPP blend, neat PLA, the PLA/15TPP/1.2Talc blend, and PLA/1.2Talc blend. The half-time of crystallization t(1/2) was increased with an increase of crystallization temperature T-c and the presence of TPP, and was decreased sharply with the incorporation of talc. Further investigation into crystallization activation energy Delta E-a of neat PLA and its blends with 15 wt % TPP and/or 1.2 wt % talc showed that the values of Delta E-a were increased with the incorporation of TPP and/or talc compared to that of neat PLA. It was verified by wide angle X-ray diffraction (WAXD) that neat PLA and its blends with TPP and/or talc crystallized isothermally in the temperature range of 113-128 degrees C, and all formed the alpha-form crystal after enough annealing time. (C) 2010 Wiley Periodicals, Inc. J Appl Polym Sci 118: 3558-3569, 2010