Hybrid thermoelectric composites consisting of organic ethylene-octene-copolymer matrices (EOC) and embedded inorganic pristine and functionalized multiwalled carbon nanotubes, carbon nanofibers or organic polyaniline and polypyrrole particles were used to form conductive nanostructures with thermoelectric properties, which at the same time had sufficient strength, elasticity, and stability. Oxygen doping of carbon nanotubes increased the concentration of carboxyl and C-O functional groups on the nanotube surfaces and enhanced the thermoelectric power of the respective composites by up to 150%. A thermocouple assembled from EOC composites generated electric current by heat supplied with a mere short touch of the finger. A practical application of this thermocouple was provided by a self-powered vapor sensor, for operation of which an electric current in the range of microvolts sufficed, and was readily induced by (waste) heat. The heat-induced energy ensured the functioning of this novel sensor device, which converted chemical signals elicited by the presence of heptane vapors to the electrical domain through the resistance changes of the comprising EOC composites.

Centre of Polymer Systems University Institute Tomas Bata University Tr T Bati 5678 760 01 Zlin Czech Republic

Department of Production Engineering Faculty of Technology Tomas Bata University in Zlin T G Masaryk nam 275 762 72 Zlin Czech Republic

Faculty of Technology Polymer Centre Tomas Bata University T G M 275 760 01 Zlin Czech Republic

The Czech Academy of Sciences Institute of Hydrodynamics Pod Patankou 5 166 12 Prague 6 Czech Republic

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Polymer Processing and Surfaces

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