Effects of dynamical cure and compatibilization on the morphology and properties of the PP/epoxy blends

In this paper, effects of dynamical cure and compatibilization on the morphology and properties of the PP/epoxy blends were studied. The addition of maleic anhydride-grafted polypropylene (MAH-g-PP) and dynamical cure of epoxy by dicyanamide give rise to decrease the average diameter of epoxy particles in the PP/epoxy blends. The epoxy particles in the PP/epoxy blends can act as effective nucleating agents, accelerating the crystallization of PP component. The dynamical cure and compatibilization increase the kinetic constant K(T) of PP crystallization in the PP/epoxy blends. Dynamical cure of the epoxy resin leads to an improvement in the modulus and strength of the PP/epoxy blends, and the addition of MAH-g-PP results in an increase in the impact strength. Dynamic mechanical thermal analysis (DMTA) results indicate that the addition of MAH-g-PP improves the compatibility between PP and epoxy resin, and the storage modulus of the PP/epoxy blends increase by dynamical cure. Thermogravimetric analysis (TGA) results show dynamical cure of epoxy and addition of MAH-g-PP improved the thermal stability of the PP/epoxy blends. Wide-angle X-ray diffraction (WAXD) analysis shows that the PP/epoxy blends have the same crystalline structure as pure PP, indicating dynamical cure and compatibilization do not disturb the crystalline structure of the PP/epoxy blends.