Sulfonated poly(ether ether sulfones) - Characterization and study of dielectrical properties by impedance spectroscopy

In this work, three samples of sulfonated polysulfones of different sulfona tion degree have been characterized, and the electrical properties of dense membranes based on them have been evaluated. The polymers were characteriz ed spectroscopically, and by their inherent viscosity, and water absorption . Electrical characterization of membranes was carried out on dense membran es in contact with NaCl solutions, by impedance spectroscopy (IS) measureme nts using equivalent circuits as models. The results showed how the sulfona tion clearly affected the membrane electrical characteristics, strongly red ucing the membrane resistance, and also changing the type of circuit associ ated to the membrane, which could be related to the increase of electrolyte taken by the membrane when the sulfonation degree increased. Concentration dependence of the electrical parameters was also studied. (C) 2000 Elsevie r Science B.V. All rights reserved.