Resistivity of epoxidized styrene-butadiene-cupric oxide polymer

Resistivity measurements versus temperature between 80 and 300 K are presented for a new compound consisting of epoxidized styrene-butadiene copolymer with star configuration and cupric oxide (CuO). For a certain concentration, 80 wt.% CuO, for which the CuO molecules are in ‘contact’, the polymer becomes conductive. For a lower concentration in CuO, the material becomes insulating, though, for a concentration higher than 80 wt.% CuO, the polymer disintegrates. The addition of CuS to the epoxidized styrene-butadiene matrix leads to a material less conductive than CuS, though IrO2 and TiO2, which contain oxygen but not Cu, form insulating materials. In addition, styrene-butadiene copolymer with configuration different than the ‘star’ one does not become conductive with the addition of any of the oxides or CuS mentioned above. From these properties the crucial role of the polymer structure, oxygen and copper in the electrical conduction of the styrene-butadiene-CuO polymer becomes apparent. Moreover, the conductivity of the epoxidized styrene-butadiene-CuO polymer is not thermally activated and its temperature dependence resembles a metal.