Comparison of mechanical properties of hybrid nanocomposites of PP/Talc/ Graphene with PP/ Graphene

In this study, the mechanical properties of PP/Graphene and PP/Talc/Graphene hybrid nanocomposites compared. All samples were prepared by melt mixing technique using an internal mixer. The coupling agent between filler and matrix was Maleic anhydride grafted polypropylene. For PP/Graphene binary nanocomposites, by adding 0.75wt. % Graphene, elastic modulus, tensile and impact strength were increased. In higher amounts of Graphene, modulus was increased while tensile and impact strength were decreased. For PP/Talc/Graphene hybrid nanocomposites, adding 15% wt. Talc to PP caused an increase in elastic modulus and a decrease in tensile and impact strength. Furthermore, after adding Graphene to PP/Talc, elastic modulus, tensile and impact strength were increased. In higher amounts of Graphene (0.75 to 1.5% wt.), tensile and impact strength were decreased. The morphology of the samples was characterized by using Scanning Electron Microscopy (SEM) technique and crystallinity behavior was characterized by Differential Scanning Calorimetry (DSC). The SEM micrographs shows that there is no good adhesion between talc and PP matrix. Also from SEM, in higher amounts of Graphene, its plates stack together. The DSC result shows that talc has no considerable effect and Graphene has negative effect on the crystallinity. The results showed that hybrid nanocomposites containing 15% wt. Talc and 1.5% wt. Graphene had highest elastic modulus while PP/Graphene nanocomposites containing 0.75% wt. Graphene had highest tensile and impact strength.