Graphene Composites

Abstract

The fabrication of composite materials is one of the effective means to enhance the performance of polymers and to produce multifunctional materials; graphene herein has been studied as the second phase. Graphene and its derivatives have attracted significant attention as promising fillers in polymer composites due to their high aspect ratio, moduli, large surface area, superb electrical conductivity, and other novel properties. It has been found that with the incorporation of a small amount of graphene, remarkable enhancement of various properties is possible. Although, mechanical exfoliation and chemical vapor deposition methods generate high-quality graphene, cost and yield factors have made it obligatory to adopt chemical routes using graphene oxide (GO). The enhancement of properties of polymer composites is dependent on the degree of dispersion of graphene in a polymer matrix as well as on the extent of interaction between the two components. Moreover, restacking between the layers of graphene owing to strong cohesive force forms agglomerates and inhibits complete exfoliation of graphene. Graphene being hydrophobic is not dispersible in either water or organic solvents. Therefore, to transfer the intriguing properties of graphene to the polymer matrix and to achieve successful reinforcement, its surface tuning is a prerequisite. The surface of graphene can be functionalized either by covalent or non-covalent methods. Engineering of graphene surface enhances its compatibility with the matrix and improves adhesion/interaction between the constituent's components. Herein, wide ranges of polymers have been included with different kinds of graphene fillers. Preparation of composites by characterization techniques have been discussed. This chapter highlights the mechanical, electrical, and thermal performance of the graphene composites and their applications in various fields.