Preparation and characterization of CNT films/silicone rubber composite with improved microwave absorption performance

Fabrications of CNT films/SR and CNT powders/SR composites are introduced to provide the rational comparisons of their thermal, mechanical and electrical properties in this work. The growth of CNT films is firstly prepared with floating catalyst chemical vapor deposition (FCCVD) method. CNT films belong to multi-walled CNT and mesoporous characteristic by Raman and nitrogen adsorption-desorption measurements, respectively. CNT films/SR composite also presents better microwave absorption performances with the low-level CNT loadings (0.5 wt%), compared to the CNT powders/SR composites. It exhibits the minimum reflection loss (RLmin) of the CNT films/SR composite is −26.55 dB and related effective absorption bandwidth (RL < −10 dB) of 3.57 GHz (12.24–15.81 GHz) with 1 mm thickness. A proposed absorption mechanism is attributed to optimized impedance matching and enhanced conductive/dielectric losses in the CNT films/SR absorber.