Graphene/MWNT/Poly(p-phenylenebenzobisoxazole) Multiphase Nanocomposite via Solution Prepolymerization with Superior Microwave Absorption Properties and Thermal Stability

This paper demonstrates both the high-performance microwave absorption properties and the superior thermal stability of graphene/multiwalled carbon nanotubes (MWNTs)/poly( p -phenylenebenzobisoxazole) (PBO) composites synthesized via in situ polymerization of functionalized PBO precursor with graphene oxide/MWNTs nanocomposites, followed by high-temperature calcination. The incorporation of three-dimensional graphene/MWNTs network significantly improved the reflection loss of PBO composites (−50.17 dB at 12.58 GHz) by over 20 times than that of pure PBO (−2.33 dB at 12.58 GHz) with a sample thickness of only 2.6 mm. The effect of graphene/MWNTs content on the microwave absorption performance was also investigated. The graphene/MWNTs/PBO composite shows great promise as a microwave absorber in high-temperature environments.