STUDY ON THE CRYSTALLIZATION BEHAVIOR OF PLA/PBS/DCP REACTIVE BLENDS

The poly (lactic acid)/poly (butylene succinate) (PLA/PBS) blends with and without dicumyl peroxide (DCP) were prepared by melt mixing and the crystallization behaviors of the blends were investigated using a differential scanning calorimeter (DSC). The results showed that the crystallization ability of PLA was not improved when it was blended with PBS because of the higher molecular weight of PBS than that of PLA in this research,which was not in accord with results of some other researchers. However, the crystallization ability of PLA in the reactive blends (PLA/PBS/DCP) was promoted after the addition of different amount of DCP, because some crosslinked (or grafted) structures were generated in this matrix, and the crosslinked (or grafted) structures acted as nucleating points. It is found that when the content of DCP was from 0.1 phr to 0.3 phr, the crystallization was mostly caused by PBS, and this crystallization reduced with increasing the DCP content. When the content of DCP was above 0.3 phr, that is to say, PLA began to crystallize when the DCP content was 0.4 phr. The crystallization of PLA was enhanced with further increasing the content of DCP,while the crystallization of PBS was weakened in the same situation. In other words, the crystallization behavior of PLA and PBS in the PLA/PBS/DCP reactive blends was mostly depended on the DCP content.