Responses of Site-Controlled, Plasticized Membrane Electrodes


Ion exchange with atomic absorption methods has been used to determine the anionic site concentrations of membranes and membrane-support materials: poly(vinyl chloride) (PVC) and carboxylated PVC. Total site concentrations can be determined. Impedance measurements of site-controlled membranes prove that not all sites are available to K+in PVC-C-OOH based neutral carrier membranes. The theory of selectivity, based on the assumption that the carrier/available site concentration ratio is the most important factor, is thoroughly tested. New results on site concentration control by tetraphenyiborate. (TPB~) and tetrakls(p-chlorophenyl)borate emphasize the systematic variation of selectivity with carrl-er/stte ratio. At low carrier levels, TPB” can be spontaneously lost from membranes until the unity carrler/slte ratio is achieved. © 1988, American Chemical Society. All rights reserved.

Publication Title

Analytical Chemistry