Advanced Materials: TechConnect Briefs 2015Advanced Materials TechConnect Briefs 2015

Graphene Chapter 4

Effect of the Kind of Carbon-Based Nanofiller on the Electrical Conductivity and Rheological Melt Behavior of Polypropylene Composites

C. Garzón, H. Palza, R. Quijada
Universidad de Chile, Chile

pp. 169 - 171

Keywords: polymer–matrix composites (PMCs), carbon-based filler, hybrid composites, electrical properties, anneling, rheological behavior

Recent interest in the use of nanoparticles for the manufacture of polymer composites has arisen due to the striking improvements in some properties achieved at lower loadings compared to micrometer fillers. In particular, derivatives of graphite (G), such as sheets of graphene and thermally reduced graphite oxide (TrGO), emerge to replace expensive carbon nanotubes (CNT). G-based particles are used today as a filler in various polymer matrices due to its amazing electrical transport properties and low cost, achieving a significant improvement in electrical properties at low percentages of incorporation (0.5-5.0 wt. %). In the present study, the effect of type of carbon structure (TrGO, G, and CNT) on the electrical conductivity and the melt behavior of polymer nanocomposites prepared by melt-mixing was analyzed. Our results show that the electrical conductivity and the melt behavior (complex viscosity) of the resulting composites strongly depends on the filler used. The lowest electrical percolation threshold is obtained when CNT is used as filler whereas when TrGO is used this threshold increases by a factor of two. The rheological results under oscillatory shear conditions at melt state showed that the rheological percolation thresholds strongly depends on the filler used.