A comprehensive study on mechanical and fracture properties of polypropylene/ethylene propylene diene monomer/halloysite blend polymer nanocomposites.

This study investigates the mechanical and fracture properties of polypropylene (PP) blend polymer nanocomposites containing ethylene propylene diene monomer (EPDM) and halloysite (HNT) fillers, focusing on both unvulcanized and dynamically vulcanized states with and without the compatibilizer polypropylene-g-maleic anhydride (PP-g-MA). Using a full factorial design and the essential work of fracture (EWF) methodology, the research found that increasing EPDM content to 20 wt.% decreased tensile strength, modulus, and EWF but significantly improved elongation at break and non-EWF, while adding 3 wt.% HNT enhanced tensile strength and fracture toughness, with higher HNT levels causing declines due to agglomeration. Dynamically vulcanized compounds and those with PP-g-MA showed superior mechanical and fracture performance compared to unvulcanized and non-compatibilized counterparts. Fractography indicated ductile fracture dominated by fibrillation and plastic deformation, and optimization suggested that dynamically vulcanized blends with 10 wt.% EPDM, 3 wt.% HNT, and PP-g-MA achieved the best balance of strength, stiffness, and toughness.