Electromagnetic modelling and experimental characterization of carbon-based nanocomposites

Carbon nanostructures such as carbon nanotubes and graphite nanoplatelets can be included in very low weight percentages in a polymer matrix to create new lightweight nanocomposites with improved performances. The development of simulation models for the prediction of the effective complex permittivity of such composites is very important for design and performance optimization purposes. In this study we propose a multiscale expression of Maxwell Garnett formula, with the aim of modeling the effective permittivity of multifiller composites, including multiwall carbon nanotubes or graphite nanoplatelets at the nanoscale, and nickel-coated short carbon fibers at the micro/macro-scale. A statistical model is also implemented in order to account for variations of the filler geometrical properties, which cannot be fully controlled at the synthesis level, in particular at the nanoscale.