Composites with carbon nanotubes and graphene: An outlook

Composite materials with carbon nanotube and graphene additives have long been considered as exciting prospects among nanotechnology applications. However, after nearly two decades of work in the area, questions remain on the practical impact of nanotube and graphene composites. This is due to factors that include poor load transfer, interfacial engineering, dispersion, and viscosity related issues that lead to processing challenges in such nanocomposites. Moreover there has not been much effort in identifying selection rules for the use of nanotubes or graphene in composite matrices for specific applications. This review is a critical look at the status of composites for developing high strength, low density, high conductivity materials with nanotubes or graphene. An outlook of the future discussing the different approaches that can lead to practically useful nanotube/graphene composites is presented, pointing out the challenges and opportunities that exist in the field.