Microwave heating of graphene nanoplatelet polymer composites: Experimental and finite element study

Abstract Compared with contemporary electrofusion techniques that use embedded wires for Joule heating, microwave heating may facilitate the joining of thermoplastic polymer components, promising shortened fusion periods, superior heating uniformity, and reduced energy consumption. This study investigates the fabrication of multifunctional polylactide acid (PLA) composites with strong microwave absorption using graphene nanoplatelets (GNP). GNP/PLA nanocomposites were fabricated using a two‐step scalable manufacturing method, that is, solution blending and hot compression molding. The GNP content of the composites ranged from 0% to 8% by weight. The samples were characterized for dielectric permittivity, heat capacity, and electrical and thermal conductivity. Thermal imaging was used to investigate the efficacy of microwave heating in GNP/PLA nanocomposites as a function of microwave power and filler weight fractions. The microwave heating process in GNP composites was studied using multi‐physics finite element software. The experimental results were compared to numerical model predictions for maximum temperature and microwave energy absorbed. The produced nanocomposites were discovered to have strong microwave absorption characteristics and hence rapid heating, making this type of composite a prospective choice for gasket materials that facilitate fusion bonding for thermoplastic‐based components via localized heating.