This work describes a green route to multifunctional nanocomposite materials composed of natural rubber (NR) latex and graphene (rGO) or graphene oxide (GO). Aqueous solutions with different concentrations of GO and rGO (prepared with the surfactant cetyltrimethylammonium bromide - CTAB) were mixed with natural rubber latex under magnetic stirring followed by sonication. The slurries obtained after casting were dried in an oven in air at 70 °C for 24 h. The nanocomposites were characterized by TEM and SEM, AFM and KFM. The thermal, electrical and mechanical properties were evaluated using TGA, resistivity measurements (four-point) and DMA. Swelling tests were performed using three solvents with different polarities: xylene, isopropanol and water. The inclusion of filler networks in the polymeric matrices provided significant improvements in the electrical, chemical and mechanical properties, in comparison to the unfilled polymer. In addition, the nanocomposites proved to be biodegradable. © 2014 Elsevier Ltd. 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