Síntese e caracterização de membranas compósitas de poli (éter-éter-cetona) sulfonado e óxido de grafeno sulfonado

Abstract

Sulfonated graphene oxide (SGO) nanoparticles were synthesized to be applied as reinforcements in sulfonated poly (ether-ether ketone) polymeric membranes (SPEEK). SPEEK-SGO nanocomposite membranes (0.25%, 0.5% and 1%) were prepared, their properties and potential application as proton exchange membranes in fuel cells (PEMFC) were investigated. The RAMAN, FTIR, FRX, XPS, DRX analyzes of the nanoparticles were carried out, which showed the effective sulfonation of graphene oxide (GO), producing SGO with sulfur contents between 57% and 61%. The titration and FRX techniques were applied to the membranes and demonstrated the success of sulfonation of poly (ether-ether-ketone) (PEEK), generating SPEEK-SGO membranes with sulfur contents between 67 and 76%. Through the TGA and DSC analyses, it was evidenced that the SGO loads, in low concentrations, promoted greater thermal stability of SPEEK in the range 100 – 200 °C. As the SGO charges increase the hydrophilicity of the polymer, facilitating the proton transport channel, an increase in the proton conductivity in the composite membrane is expected. Therefore, SPEEK-SGO composite membranes are applicable as PEMFC.