Abstract:DSC, SEM, 2D-WAXD and high-pressure capillary were used to investigatethe effects of changing processing parameters and PA6 phase on the crystalline properties,phase evolution,rheological and mechanical properties of iPP/PA6 blends. The results of high-pressure capillary show that the introduction of PA6 can significantly reduce the shear viscosity. Relative to conventional injection molding, the higher shear flow field and cooling rate in micro injection molding can induce the evolution of dispersed phase PA6 from spherical to rod or in-situ microfibers. The well-formed PA6 fibers were formed in both the central layer and the oriented layer in the micro-injection iPP/PA6 samples. Increasing injection speed can enhance the β content from 22% to 33% (iPP), and decrease the diameter of PA6 fiber, from 2.38 μm to 0.36 μm. In addition, introducing PA6 into iPP/PA6 blends can decrease the molecular orientation degree from 0.91 to 0.88 and enhance the tensile strength from 34.2 MPa to 37.5 MPa.