The effect of the length of blending rime and the effect of a second blending of dynamically vulcanizing EPDM/PP on its morphology

PP crystallinity (xc)

effective network chain density (vs) and tensile properties were studied by SEM.TEM

DSC and WAXD. EM observations indicated that the dispersed EPDM diminished in size with length of blending time and the second blending. Xc of PP decreased with blending time but increased after 13 minutes

whereas tensile strength of the blends was observed to behave in the opposite direction. Vc continued to decrease in the blending. Xc and Ve became lower but tensile strength higher after the second blending at various blend ratios. Tensile strength was linked to the fine dispersion of EPDM particles in PP and the interfacial interaction of EPDM with the amorphous part of the semicrystalline PP.