Preparation of Microwave Absorbing E‐Glass/Epoxy Nanocomposites with Low Content of Binary Carbon Nanofillers

Abstract

ABSTRACTThe nanocomposite microwave absorbers are prepared from laminates of E glass/epoxy matrix with the incorporation of multiwalled carbon nanotubes (MWCNTs) and detonation nanodiamond (DND). Nanodiamond particles are used to effectively and uniformly disperse the carbon nanotubes in the polymer matrix, leading to a very homogenous mixture. The results showed that microwave absorption of nanocomposites increases with the increase in MWCNTs concentration in 11–17 GHz frequency range. The maximum loss of –28 dB was obtained at 14 GHz. The bandwidth corresponding to the reflection loss of −10 dB is 4.5 GHz. The mechanical properties are also improved after incorporating MWCNTs and DND in the composite. The tensile strength has been increased by ∼113% after the addition of 1.0 wt% MWCNTs and 0.1 wt% DND. The morphological investigation demonstrated that coating of MWCNTs on the surface of the woven glass fibers in the presence of DND resulted in uniform dispersion of nanotubes throughout the matrix with the formation of connected networks that helps in electrical conduction and load transfer between the nanofillers and the matrix. The role of MWCNTs and DND particles in enhancing the electromagnetic absorption and mechanical properties of the nanocomposite laminates is explained.