title: New sulfonated polystyrene and styrene-ethylene/butylene-styrene block copolymers for applications in electrodialysis.
abstract: In this study we prepared blends of polystyrene (PS) and high-impact polystyrene (HIPS) with poly(styrene-ethylene-butylene) (SEBS) triblock copolymer. After sulfonation, blends were used to fabricate ion-exchange membranes by solvent-casting and subsequent thermal treatment to obtain homogeneous packing densities. The morphology and structure of the blends were investigated by scanning electron microscopy, atomic force microscopy, and FTIR spectroscopy. Furthermore, the thermal transitions and stability of all the blends were characterized using calorimetric techniques and compared with those of the individual polymers. Analyses of the physical properties (i.e., ionic conductivity, ion-exchange capacity, water uptake, dimensional stability, mechanical properties, etc.) showed that the performance of the PS-containing membranes is, in general, higher than that of the HIPS containing one. Furthermore, the highest sulfonation degree was also found for the PS/SEBS membranes. The capabilities of the membranes were tested by investigating the extraction of Na(+) by electrodyalisis. Comparison of the percentage of extracted ions indicates that the incorporation of SEBS results in a significant improvement with respect to membranes made of individual polymers.
authors.affiliation: Departamento de Engenharia de Materiais, PPGEM, Universidade Federal do Rio Grande do Sul, Av. Bento Gonçalvez, 9500, Setor 4, Prédio 74- 91501-970, Porto Alegre (RS), Brazil.
authors.forename: Franciélli
authors.initials: F
authors.lastname: Müller
authors.forename: Carlos A
authors.initials: CA
authors.lastname: Ferreira
authors.forename: Lourdes
authors.initials: L
authors.lastname: Franco
authors.forename: Jordi
authors.initials: J
authors.lastname: Puiggalí
authors.forename: Carlos
authors.initials: C
authors.lastname: Alemán
authors.forename: Elaine
authors.initials: E
authors.lastname: Armelin
mesh_terms: D004553:Electric Conductivity; D015394:Molecular Structure; D011137:Polystyrenes / Q000737:chemistry*; D012995:Solubility; D013696:Temperature; D018508:Water Purification
chemical_list: D011137:Polystyrenes; C577251:poly(styrene-ethylene-butylene)