Response and Application in Dipolar Aprotic Solvents of Ion-Selective Electrodes Based on Polyacrylamide Modified with Acyclic Poly(oxyethylene) Derivatives

Abstract

Abstract The response of organic polymer membrane electrodes, constructed by coating a platinum disk with polyacrylamide (PAA) coupled to acyclic poly(oxyethylene) derivatives, tetraethylene glycol monododecyl ether (POE4) and hexaethylene glycol monododecyl ether (POE6) was studied in acetonitrile (AN) and N,N-dimethylformamide (DMF). The PAA–POE4 electrode showed Nernstian response to the lithium ion in AN and the magnesium and barium ions in DMF, while the PAA–POE6 electrode showed near Nernstian response to the barium ion in DMF. The PAA–POE4 electrode was applied to study the complexation of the lithium ion in AN with DMF. The formation constants, β1=17 and β2=1.2×102, obtained agreed well with the values obtained previously with an univalent cation sensitive glass electrode. The response of the PAA-POE4 electrode in barium bis(2-ethylhexyl) sulfosuccinate (Ba(DSS)2)–DMF solution has been studied and the results are explained by taking the conductometrically determined association constant (K1A=5.2×102) between Ba2+ and DSS− ions.