On the mechanical properties of melt-blended nylon 6/ethylene-octene copolymer/graphene nanoplatelet nanocomposites

Ethylene-octene copolymer (EOC) with a loading level of 20 wt%, maleated EOC (EOC-g-MA) with a loading level of 3 wt% and graphene nanoplatelets (GnPs) at four different loading levels, i.e., 3 wt%, 5 wt%, 10 wt% and 15 wt% were added to nylon 6 to prepare nanocomposites using a twin-screw extruder with a high shear rate screw running at 300 rpm. Increased stiffness was observed with the addition of GnPs while tensile strength of nanocomposites was only slightly influenced. Addition of GnPs into nylon 6 and nylon 6/EOC blend caused either a reduction in the Charpy impact strength or it remained unaffected. Similarly, the Izod impact strength of compatibilized nylon 6/EOC blend increased while that of nylon 6/EOC blend-based nanocomposites decreased. An increase was observed in the compressive Izod impact strength of compatibilized nylon 6/EOC blend. Addition of GnPs to nylon 6/EOC blend caused an increase in the fracture toughness due to their influence on the morphology and fracture mechanisms. This study shows that simultaneous addition of high surface area GnPs and an impact modifier to neat nylon 6 can help achieve enhancement and tailoring of stiffness and toughness. [Display omitted] •Adding stiff nanoparticles and thermoplastic elastomer to nylon 6 can help achieve a balance of mechanical properties.•Mechanical properties are enhanced through optimal nanoparticle loading and controlled processing conditions.•The morphology of the nanocomposite strongly influences its mechanical properties.•Ethylene-octene copolymer, along with malleated ethylene-octene copolymer, serves as a strong toughening agent for nylon 6.