Binding of electrolytes to poly(ethylene oxide) in aqueous solutions

3878

Macromolecules 1990,23, 3878-3881

Binding of Electrolytes to Poly(ethy1ene oxide) in Aqueous Solutions R. Sartori Departamento de Quimica y Bioquimica, Facultad de Medicina Norte, Universidad de Chile, Independencia 1027, Santiago, Chile

L. Sepulvedat Departamento de Quimica, Facultad de Ciencias, Uniuersidad de Chile, Las Palmeras 3425, Santiago, Chile

F. Quina Departamento de Quimica, Unioersidade de Santa Catarina, C.P. 476, Florianopolis 88049, Brasil

E. Lissi a n d E. Abuin' Departamento de Quimica, Facultad de Ciencias, Unioersidad de Santiago de Chile, Casilla 5659, Correo 2, Santiago, Chile Received October 3, 1989; Revised Manuscript Received January 25, 1990 ABSTRACT Ion selective electrode and ultrafiltration measurements have been employed to investigate the extent of electrolyte binding to poly(ethy1eneoxide) in aqueous solution. Although lithium chloride does not interact measurably with the polymer, significant binding is verified for sodium, potassium, rubidium, and cesium chlorides and for a series of other potassium salts. For the chlorides, operationalbinding constants, whose magnitudes depend on electrolyte and polymer concentrations,follow the sequence lithium