Nonisothermal crystallization kinetics of PLA/nanosized YVO₄ composites as a novel nucleating agent

The influence of nanosized YVO4 particles as a novel and efficient nucleating agent on the nonisothermal crystallization behaviors of poly(lactic acid) (PLA) was studied. A modified Avrami model was utilized to describe the nonisothermal crystallization kinetics of pure PLA and PLA nanocomposites. The differential isoconversional Friedmann formula was employed to calculate the effective activation energies (E-X(t)) of nonisothermal crystallization from the glass state. The results showed that modified Avrami methods describe the nonisothermal crystallization kinetics of pure PLA and PLA nanocomposites well. The crystallization rate of PLA/1 mass% YVO4 was faster than that of pure PLA sample by factor 5 x 10(3) at a heating rate of 1 K min(-1). While the values of Lauritzen-Hoffman parameters (K-g and U*) of the PLA/YVO4 nanocomposites were lower than those of pure PLA, indicating the nucleation efficiency of nanosized YVO4 particles for PLA. Scanning electron microscopy images reflect the uniform dispersion of 1 mass% YVO4 in PLA matrix. Thermogravimetric analysis results revealed that the thermal degradation parameters are slightly lowered by 7 degrees C on increasing the mass percentage of YVO4 in the PLA nanocomposites. (c) 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 48340.