ABSTRACT
Graphene nanoplatelets (GNPs) are tiny stacks of graphene layers with thicknesses ranging from 1 to several nanometers and lateral size from hundreds of nanometers to several micrometers. Depending on the fabrication route, GNPs can be produced starting from different precursors, such as graphene oxide (GO) or graphite intercalation compounds (GICs): both routes are compatible with mass production. Polymeric nanocomposites are drawing ever-growing attention thanks to their light weight and the possibility to dramatically increase the matrix properties using very low ller loadings. The main challenge in the practical application of GNP and GNP-based nanocomposites consists of tailoring their functional properties through the control of the synthesis process, using a suitable modeling tool that allows correlating the micro/nanostructure of the material to its functional
properties at macroscale. This chapter focuses on the development of GNPs and GNP-based polymer composites with tailored electrical, electromagnetic, and electromechanical properties for applications such as shielding or radar-absorbing materials (RAMs), or piezoresistive strain sensors. We demonstrate the proper control of the morphological characteristics of GNPs and the nal functional properties of the nanocomposite (namely, the effective complex permittivity, shielding effectiveness or reection coefcient, the piezoresistive response) through the proper setting of the synthesis route and of the type of polymeric matrix used. Different parameters are investigated, such as the precursor expansion time and temperature, the exfoliated graphite sonication cycle, the type of solvent used, and the suspension temperature during sonication. A novel simulation model is developed to predict the effective electromagnetic properties of GNP nanocomposites.
Abstract ..................................................................................................................................................................................... 507 31.1 Introduction ..................................................................................................................................................................... 508 31.2 Graphene Nanoplatelets: Synthesis and Characterization ............................................................................................... 509 31.3 DC Electrical Conductivity of GNP Papers: Effect of Process Parameters ..................................................................... 511
