Graphene based impact modified polypropylene nanocomposites for automotive applications

Abstract

Graphene-based nanocomposites demonstrate superior electrical, mechanical, physical and thermal properties. Because of this, they have moved swiftly from the research laboratory into the marketplace in applications including: aerospace, automotive, coatings, electronics, energy storage, coatings and paints. Based on the huge interest, enhanced properties as well as ease of production and handling, the European Union is funding a 10 year $1.73 billion coordination action on graphene. South Korea is spending $350 million on commercialization initiatives and the United Kingdom is investing $76 million in a commercialization hub), since many of the current and potential applications of carbon nanotubes may be replaced by graphene at much lower cost. The main objective of this study was to characterize the influence of exfoliated graphene nanoplatelet (xGnP) particle diameter, filler loading and the addition of coupling agents on the mechanical, rheological and thermal properties of xGnP-filled impact modified polypropylene (IMPP) composites. The xGnP nanoparticles used in this research were of three different sizes: xGnP5 with an average thickness of 10 nm, and an average platelet diameter of 5 ?n, whereas xGnP15 and xGnP25 have the same thickness but average diameters are 15 ?n and 25 ?n, respectively. The coupling agent used in this study was polypropylene-graft-maleic anhydride (PP-g-MA). Test results show that nanocomposites with smaller xGnP diameter exhibited better flexural, tensile and impact properties for both neat IMPP and composites containing coupling agent. For composites containing a coupling agent, the tensile and flexural modulus and strength increased with the addition of xGnP. The TGA results indicated that the degradation temperature of IMPP is lowered with the addition of PP-g-MA, indicative of the poor thermal stability of PP-g-MA. However, the thermal stability of the composites increases with xGnP loading because of the high thermal stability of the xGnP. Microscopy, rheology, thermal analysis including dynamic mechanical thermal analysis and differential scanning calorimetry were also used to study the processing, structure, and properties of the nanocomposites. © 2015 Elsevier B.V., All rights reserved.