▎ 摘　　要

Double-shell hollow conductive poly(acrylonitrile) microspheres@polyaniline@Ag (PANS@PANI@Ag) was synthesized by a facile two-step method. Polyaniline-coated poly(acrylonitrile) microspheres (PANS@PANI) prepared by in situ polymerization exhibited a porous, corrugated and compact conductive network, making for the formation and attachment of Ag nanoparticles. Incorporating these hollow conductive spheres and reduced graphene oxide (RGO) into epoxy resin, a lightweight microwave absorber was brought out. The chemical composition, micro-structure surface morphology and electromagnetic properties were thoroughly characterized and analyzed. The calculated results showed that the optimal reflection loss (RL) was -44.9dB at 9.16GHz with a constitution of 1wt% dielectric RGO and 1wt% conductive PANS@PANI@Ag, and the corresponding effective bandwidth was about 2GHz. However, the microwave absorption capacity gradually reduced with the raise of PANS@PANI@Ag content, derived from the high conductivity leading to more microwave reflection. As the PANS@PANI@Ag content increased to 5wt%, the minimum RL was -14.7dB and still remained an effective absorption performance with a lower density of 0.47-0.53g/cm(3). Therefore, the as-obtained composites paved a new route for lightweight and strong absorption microwave absorbers in commercial and military application.