Membranas de poliétersulfona/argila e sua permeabilidade à água

Abstract

Membranes can be considered polymeric or inorganic films that function as a semipermeable barrier to filtra-tion on a molecular scale, separating two phases and restricting, totally or partially, the transportation of one or more chemical species (solute) present in the solution. Therefore, the aim of this work is to produce poly-ethersulfone membranes (PES) and polyethersulfone/clay by phase inversion technique and evaluate the presence of clay in obtaining membranes for wastewater treatment. The used solvent was dimethylformamide (DMF) and clays were Brasgel PA (MMT) and Cloisite Na (CL Na) in the proportion of 3 to 5% (wt.). By X-ray diffraction (XRD), the membranes with 3% of MMT and CL Na clays apparently had partially exfoliated structures. For the composition with 5% of CL Na a small peak was observed, which indicates that this is possibly an intercalated structure or microcomposite. By scanning electron microscopy (SEM), visualizes that the pure suface of the pure PES membrane a structure apparently without pores was observed in the used magnification and without roughness surface when compared to membranes with clay. The measurements of contact angle indicated that the inclusion of clay altered the wetting ability of the membranes. The flow with distilled water for all membranes started high and over time reached a stabilization level. Thus, it can be con-cluded that the presence and the content of clay altered the morphology of the membrane, contributing to an increase in water flow