SYNTHESIS AND CHARACTERIZATION OF COMPOSITE MATERIALS FOR APPLICATION IN FILTRATION MEMBRANE
Membranes are barriers that allow the separation of materials depending on their physical and chemical properties. They present a higher performance when compared to conventional filters due to the large size of their surface area and smaller pores. The main materials used to prepare the membranes present low hydrophilic properties being susceptible to fouling problems. Aiming to reduce those problems, this work suggests the synthesis of conductive composite materials, of polyaniline and graphene oxide for modification of poly (ether sulfones) membranes. The polyaniline (PANI) is the most studied intrinsic conducting polymer, because of some important characteristics such as the low-cost monomer, the known polymerization process, the excellent stability in environmental conditions, and the possibility to control your insulating-conductor state in a controlled manner. In this way, the purpose of this work is the synthesis and characterization of polyaniline and graphene oxide (GO) films, aiming to modify the poly (sulfone ether) membranes to decrease the fouling effect, and to produce a conductive membrane, respectively. The films were obtained using the casting technique, from a solution of polyaniline in N-methyl-2pyrrolidone (NMP), 3 wt%. Then, the obtained films were doped by immersion using two types of acids: the hydrochloric acid (HCl) and camphor sulfonic acid (HCSA), for different time intervals. Two different proportions for the dispersed phase of GO were tested, 0.5 and 0.74% in relation to PANI. The synthesized materials were characterized by UV-Vis spectroscopy and Raman spectroscopy, morphologically by scanning electron microscopy and electrically using the four-point probe technique. As a result, the 0.74% PANI-GO films showed an improvement in electrical conductivity, the film doped with hydrochloric acid showed conductivity levels from 20.14 to 85.97 (S.cm-1), being an interesting material for the modification of membranes.