Thermomechanical degradation of PP based nanocomposites filled with graphene nanoplatelets

Graphitic nanofillers have extensively used to prepare nanocomposites based on both conventional petroleum based plastics and bio-based polymers . Among them, graphene or graphite nanoplatelets (GnP), also called graphite nanosheets or nanoflakes, are a relatively new carbon nanomaterial composed of stacked 2D graphene sheets with outstanding electrical, thermal and mechanical properties. Indeed, by adding GnP, also at low filler concentration (< 5 wt.%), the mechanical, heat-resistance, thermal and electrical properties of the polymer matrix can surprisingly enhance due to unique properties of these nanofillers. However, the characteristics of these multiphase systems certainly depend on the nature of the components but also on the final morphology achieved in the materials. Controlling the dispersion and the dimension of the particles is, therefore, a critical factor for the success in practical applications. Aim of this work was to study the effect of the mixing conditions on the properties of polypropylene (PP) filled with graphene nanoplatelets (GnP). In particular, the effect of processing temperature and mixing time on morphology, rheological and mechanical properties of PP/GnP nanocomposites was evaluated. Moreover, the effect of the GnP amount on the investigated properties was studied.