Carbon nanotubes based nanocomposite for electromagnetic wave absorption and dynamic structural strain sensing

摘要

Carbon nanotubes (CNTs)-polymethyl methacrylate (PMMA) nanocomposites have been developed for electromagnetic wave absorption (EWA) and dynamic strain sensing in for structural health monitoring. For the purpose CVD synthesized CNTs were characterized for its structural and morphology using X-ray diffraction (XRD) patterns and scanning electron microscopy (SEM) before preparing nanocomposite. The CNTs obtained were of about 10 nm diameter and 0.5 μm length. The prepared CNT/PMMA nanocomposite films (CNT 5% loading) were characterized for their electrical proprities, indicating metallic (resistive) behaviour and electromagnetic absorbance (EWA) behaviour in the X and Ku band showing absorption peaks of around 3.5 dB loss at 8.5 GHz and 20 dB loss at 14.5 GHz. The peppered CNT/PMMA nanocomposite films were used in strain sensor applications for structural health monitoring. The strain sensor results closely matched with standard strain gauge sensor under quasi static as well as dynamic conditions.