writer：Defeng Wu, Chixing Zhou, Fan Xie, Dalian Mao, Bian Zhang.
keywords：crystallization; PBT; clay; nanocomposites.
source：期刊
specific source：Journal of Applied Polymer Science
Issue time：2006年

Journal of Applied Polymer Science, 2006, 99, 2534.

ABSTRACT: The melt intercalation method was employed to prepare the poly (butylene terephthalate)/montmorillonite (PBT/MMT) nanocomposites, and the microstructures were characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). Then the nonisothermal crystallization behavior of nanocomposites was studied by differential scanning calorimetry (DSC). The DSC results showed that the exothermic peaks for the nanocomposites distinctly shifted to lower temperatures at various cooling rates compared with that for pure PBT and, with increasing in MMT content, the peak crystallization temperature of the PBT/MMT hybrids declined gradually. The nonisothermal crystallization kinetics was analyzed by Avrami, Jeziorny, Ozawa and Mo methods based on the DSC data. The results revealed that the very small amounts of clay (1wt%) could accelerate the crystallization process whereas higher clay loadings reduce the rate of crystallization. In addition, the activation energy for the transport of the macromolecular segments to the growing surface was determined by the Kissinger method. The results clearly indicated that the hybrids with small amounts of clay presented relative lower activation energy than that of PBT, while those in higher clay loadings showed the higher one. The MMT content and the crystallization conditions as well as the nature of matrix itself affect the crystallization behavior of the hybrids.