ABSTRACT
Abstract. Smart windows which regulate the transmission of visible light are well known, but with the continuing interest in modifying the radar signature of military hardware, there is a need also for smart microwave windows and surfaces. The paper reviews progress on the fabrication and characterisation of poly(aniline)-silver-polymer electrolyte composite materials. Discs and films of this material have been characterised over the frequency range 0.5-18GHz. The materials demonstrate a rapid and reversible change in their microwave reflectivity when a small DC potential is applied across them. The best samples have exhibited a reflectivity change in excess of 20dB in a coaxial line test cell. Cyclic voltammetry studies of these composite materials are discussed in the light of a poly(aniline) | polymer electrolyte | silver single cell model. The effect of the poly(aniline) counter-ion, the polymer electrolyte and the application of a bias potential on the DC and microwave results is discussed. Geometries of smart surfaces which might utilise these materials are then proposed and their characteristics are evaluated.
