ANÁLISIS DE PROPIEDADES SUPERFICIALES Y TÉRMICAS DE MEMBRANAS COMPUESTAS DE POLI(ALCOHOL VINÍLICO) DEPOSITADO SOBRE MEMBRANAS POROSAS DE POLIETERSULFONA

ELZA F. CASTRO; MARIA TORO; BETINA VILLAGRA DI CARLO; ALBERTO HABERT

Cordoba

Congreso; 16º Congreso Internacional de Metalurgia y Materiales SAM-CONAMET 2016.; 2016

Universidad Nacional de Córdoba

The composite membranes were manufactured with crosslinking poly(vinyl alcohol) on polyethersulfoneporous membranes by coating process. PES membranes were exposed to air plasma for the purpose ofsurface modification. The coating of the support membrane was carried out by using a polymer matrix with acrosslinking agent. The physico-chemical properties have been studied by attenuated total reflectancefourier transform infrared spectroscopy (ATR-FTIR) and contact angle measurements. The surfacemorphologies were characterized by the method of surface area applying atomic force microscopy (AFM).Thermal stability properties and phases transition of the composite membranes were investigated by thermalgravimetric analysis (TGA) and differential scanning calorimetry (DSC) [1]. Poly(vinyl alcohol) is a watersoluble,hydrophilic and biodegradable polymer with excellent film forming properties. However, PVA must be crosslinked by modification reactions with a crosslinking agent to form a stable membrane with goodmechanical properties in pervaporation [2]. PVA was used as the dense polymer with maleic acid as acrosslinking agent. Fourier transformed infrared spectroscopy revealed the nature of the surface chemical.Contact angle measurements have been used for evaluating changes in wetting properties. The air-plasmatreatment caused an effective surface modification. The mechanism responsible for the wettabilityimprovement was the surface functionalization by insertion of polar groups. The roughness profiles forcrosslinked PVA and PES substrates were obtained. Introduction of maleic acid into the polymer chainincreased the amorphous region of the membrane. The PVA is a semi-crystalline polymer exhibiting both aglass transition temperature (Tg) and a melting isotherm (Tm), as evidenced in the DSC thermogram [3].Thermal properties of the composite membranes were significantly enhanced. Both, the decompositiontemperature and the residual weight increased when compared with dense PVA membranes. The chemicallycrosslinked PVA with maleic acid resulted in the formation of composite membranes with improvedpervaporation properties for separation application.