Novel composites with a cross-linked polyaniline shell and oriented palygorskite as ideal microwave absorbers

Abstract

It is a bold and highly novel attempt to disperse a conductive polymer with clay to enhance its microwave absorption performance. In this paper, we demonstrate that the introduction of palygorskite can effectively prevent polyaniline from aggregation and guide polyaniline on the nanorods of palygorskite. Interestingly, the obtained palygorskite/polyaniline (PAL/PANI) composites exhibit a cross-linked shell structure and the thickness of the polymer shell can be adjusted by controlling the content of palygorskite, which has a positive effect on the microwave absorption performance of the materials, due to improved impedance matching and increased attenuation constant. The optimized sample shows a reflection loss (RL) value of −57.40 dB at 11.04 GHz, at a thickness of 2.41 mm. Meanwhile, the effective absorption bandwidth reaches 5.20 GHz in the range of 11.84–17.04 GHz. It is believed that this achievement can be used as a reference for the design of composite materials as low-cost high-performance microwave absorbers.