Abstract: In this study, the molecular orientation distributions and crystalline structure in the thickness direction of injection molded PP/PET blends were characterized by twodimensional wideangle Xray scattering (2DWAXS). It showed that the orientation parameters for PP/PET blends were lower than neat PP in every layer. Furthermore, the distinction of orientation parameters of the blends between skin layer and core region was also smaller than pure samples. In the sample of compatibilized PP/PET, the orientation parameter along the thickness was about 0.3～0.4, which indicated that the skincore structure of this sample was greatly restrained. Addition of carbon nanotubes(CNTs) accelerated the crystallization rate of PET dispersed phase, and increased the crystallinity. After addition of CNTs, its bending modulus was 20 % higher than pure PP.

Key words: polypropylene, poly(ethylene terephthalate), injection molding, orientation structure