Fabrication and evaluation of conducting polymer composites as radar absorbers

Conducting polymer materials have the potential for replacing metals in many electromagnetic shielding applications where the special properties of plastics and their composites are preferred to those of metals and other inorganic conductors such as carbon. There is also the whole field of radar signature management where there is a requirement for surfaces or layers with specified impedances. The authors presented results of preparing and characterising the conducting polymer polypyrrole (PP) grown on a cellulose (paper) substrate with prescribed impedance loadings. However, the use of textile materials as substrates is widely used in industrial processes and these materials offer more possibilities for control of a composite material. They report the fabrication and characterisation of PP-loaded fabrics, and their application in microwave absorbing structures. Unlike some other conducting polymers (such as polyacetylene) PP in its oxidised state has good stability in air and is robust with respect to the temperatures normally required for embedding in resin, for example. A brief summary is included of its formation and electronic properties