Thermal and electrical properties enhancement of a nanocomposite of industrial silicone rubber filled with reduced graphene oxide

In this work, a nanocomposite was developed by in-situ polymerization using industrial-grade diatom-containing silicone rubber (SR) as the matrix and reduced graphene oxide (RGO) as filler. The Concentration of RGO, was very low, varying from 0 to 1 wt%. In these nanocomposites, diatoms as well as RGO flakes of sizes smaller than 20 µm were dispersed homogeneously within the SR. According to thermogravimetric analysis (TGA), the thermal stability of the composite is improved by increasing the decomposition temperature of SR from 497 °C to 546 °C at 0.8 wt% of RGO. A TGA signal between 620 °C and 670 °C is identified as due to C-C bonds thermal breaking, whose integrated intensity increases in proportion to the concentration of RGO and can be used to determine the concentration of RGO in similar composite systems. When 1.0 wt% of RGO is added thermal conductivity increases by 47.5% and the electrical resistivity decreases four orders of magnitude, respect to SR values. The SR/RGO nanocomposite is flexible and represents a good candidate for applications in the development of sensors and biomedical applications. The use of industrial-grade SR reduces production costs of composites in comparison to those prepared with more expensive analytical grade rubbers.