Characterization Of Multifunctional Nanocomposites With Respect To Their Electrical Properties

Abstract

Heightened concerns for electromagnetic interference (EMI) in civilian and defence applications have led to the development of multi-functional materials that can provide structural performance while shielding electronic components from electromagnetic waves. Since EMI shielding effectiveness is highly dependent on electrical properties, the goal of this chapter is to present information on how to characterize the conductivity, permittivity and resistivity of nanocomposites; particularly those formed using fiber and carbon nanotube (CNT) reinforced polymer composites. The key components of the nanocomposites are synthetic carbon nanofibers (CNTs). In this chapter, an example will also be provided for a case where the CNTs are embedded in the fiber reinforced material in the form of a non-woven CNT textile, which is proprietary and may be obtained from Nanocomp Technologies Inc. (www.nanocomptech.com). To measure the electrical properties of the nanocomposite, such as conductivity and resistivity, electrical testing of specimens can be conducted using a low frequency impedance analyser. The textile based nanocomposite material’s EMI shielding effectiveness was estimated to be approximately 46 dB for a resistivity of 0.88 ohm/square. Given the material’s average area density of 12.8 g/m 2 , these results can be considered promising since the Nanocomp material can be incorporated into