NEW METHOD FOR DETERMINING THE CONCENTRATION OF IONIC IMPURITIES IN SOLVENT POLYMERIC MEMBRANES

Authors
NAGELE M PRETSCH E
Citation
M. Nagele et E. Pretsch, NEW METHOD FOR DETERMINING THE CONCENTRATION OF IONIC IMPURITIES IN SOLVENT POLYMERIC MEMBRANES, Mikrochimica acta, 121(1-4), 1995, pp. 269-279
Citations number
39
Categorie Soggetti
Chemistry Analytical
Journal title
Mikrochimica acta → ACNP
ISSN journal
00263672
Volume
121
Issue
1-4
Year of publication
1995
Pages
269 - 279
Database
ISI
SICI code
0026-3672(1995)121:1-4<269:NMFDTC>2.0.ZU;2-Q
Abstract
A new method is proposed for ascertaining the amount of ionic impuriti es in solvent polymeric membranes of ion-selective electrodes. The met hod is based on determining the selectivity coefficient for ions of di fferent valences as a function of the concentration of a lipophilized tetraphenylborate salt added to the membrane phase. Thus, the concentr ation of anionic impurities in commercially available poly(vinyl chlor ide) and of cationic ones in Tecoflex(R) (a polyurethane) was obtained as 0.063 +/- 0.016 and 0.044 +/- 0.006 mmol/kg, respectively.