Effects of Multi-walled Carbon Nanotubes on the Microwave Absorbing Properties of Magnetorheological Elastomers

Abstract

Abstract The microwave absorbing properties of carbonyl iron particles (CIPs) based magnetoheological elastomer (MRE) filled with multi-walled carbon nanotubes (MWCNTs) were examined. Absorbents including the CIPs and MWCNTs were mixed and added to the silicone rubber (SR) matrix for further compression molding and vulcanization. The complex permittivity and complex permeability were measured over a frequency range of 2-18GHz. As the MWCNT weight percentage increased, the reflection loss (RL) of the MRE composites changed significantly, which is attributed to the impedance mismatch. The MRE composites containing 28 wt% CIPs and 0.1 wt% MWCNTs with a thickness of 3 mm display dual resonance peaks with a maximum RL of -53 dB and the effective frequency bandwidth (RL<-10dB) reaches 7.7 GHz. This suggests that the MRE composites could serve as a potential candidate for absorbing incident microwave with excellent flexibility.