Towards next-generation fiber-reinforced polymer composites: a perspective on multifunctionality

Polymer composite materials and structures with multiscale additives have great potential applications in various fields due to their outstanding features, such as extraordinary mechanical, thermal, electrical, and other properties. Multifunctionality can be achieved by exploiting these properties for practical applications. Next-generation fiber-reinforced polymer (FRP) composites will have significant secondary functions besides their conventional primary feature-high strength-to-weight ratio. A key concept that would enable the large-scale manufacturing and application of multifunctional FRPs is 'design for multifunctionality', which uses material design tools, such as integrated computational materials engineering (ICME), to facilitate innovations in materials. In this review, we examined recent research and studies on novel functions of FRPs and the matrices, reinforcements, and fillers that enable these functions. The functions included in the scope of this study include sensing, actuation, self-healing, heat resistance, thermal insulation/dissipation, electrical isolation/conduction, energy harvesting, electromagnetic shielding, etc. In addition, the design, modeling, and manufacturing processes of these functional FRPs were discussed. This review aims to serve as a collection of knowledge that supports the ICME of next-generation FRPs and a catalog of function enablers from the novel material developers' perspective.