Ultralight hard carbon nanotubes nanofiber foam/epoxy nanocomposites for comprehensive microwave absorption performance

In this study, a novel three-dimensional carbon nanotubes (CNTs) structure was constructed using a phenolic resin template method, which has a multilevel microporous structure and a woven CNTs network microstructure. The CNTs nanofiber foam/epoxy composite was prepared by a vacuum impregnation method. Due to the multiple reflections and interface effects produced by the special structure, the best microwave absorption effect is achieved with a lower CNTs content. When the CNTs content is 0.92 wt%, the lowest reflection loss is −42.13 dB (6.6 GHz, 2.9 mm). Under the premise of not adding magnetic loss materials, only CNTs are used as a reinforcing material, and a resin matrix composite with excellent electromagnetic wave absorption performance without micropore defects is obtained. This method has universal applicability and broadens the further application of resin matrix composite in the aerospace and electronic fields.