Mechanical, thermal, and rheological properties of graphene-based polypropylene nanocomposites prepared by melt mixing

In this article, we describe the fabrication by melt mixing of graphene-polypropylene nanocomposites and present the effect of graphene addition on some selected properties of polypropylene (PP). The graphene nanosheets (GNs) used as nano-reinforcing agents were obtained through chemical reduction of graphene oxide by hydrazine hydrate. GNs were characterized and successfully dispersed into PP matrix to produce PP/GNs nanocomposites. The effects of GNs content on thermal, mechanical, and rheological properties were reported, and the obtained results were discussed in terms of morphology and state of dispersion and distribution of the GNs within the polymer matrix. Characterization by scanning electron microscopy and X-ray diffraction of the nanocomposites has shown a relatively good dispersion of GNs in the polymer matrix, with the presence of only few aggregates. Increasing GNs content resulted in a significant increase in both mechanical and thermal properties with only few percent of GNs loading. Rheological behavior of the PP/GNs nanocomposites showed a Maxwellian-like behavior for low GNs concentrations and a viscoelastic solid-like behavior for GNs content exceeding the concentration of the percolation threshold. POLYM. COMPOS., 2012. (c) 2012 Society of Plastics Engineers