Nanostructured materials: Thermoelectic switches based on polyisoprene/silver microcomposites

Conductive polyisoprene/silver microcomposite films were prepared and electrically stabilized by a photochemical crosslinking treatment. The films showed a very stable and reproducible conductor-insulator transition at a temperature of ca. 55¡C. In addition, crosslinking removed the negative coefficient temperature (NTC) effect and hysteresis phenomena. These photochemical treatment results are applicable for thermoelectric devices manufactured in the form of supported films. Metal/polymer microcomposites (i.e., fine metal powder dispersions in polymeric matrices) combine low cost, easy processing, and excellent mechanical properties of plastics with thermal, electric, and magnetic properties of metals [1,2]. In addition, novel physical characteristics are observed, e.g., these materials strongly absorb microwave producing heat, they show temperature-dependent electrical properties, and absorb all types of nuclear radiations.