A conductive plastic for simulating biological tissue at microwave frequencies

A conductive plastic composite that exhibits complex dielectric properties similar to biological tissues over the electromagnetic spectrum of 300-900 MHz has been synthesized from compressed carbon black mixed with a castable thermoplastic (polyethyl methacrylate). This paper presents the techniques used to control the electrical properties of the conductive plastic and describes the challenges encountered in fabricating a material containing a high proportion of carbon black. While developed to serve as a housing material for a microwave antenna array for imaging biological bodies, the composite should be useful in any setting requiring a stable, solid, high loss material that simulates biological tissues over the microwave spectrum.

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