Electrostatic Surface Potential and Critical Micelle Concentration Relationship for Ionic Micelles

Abstract

The relationship between the micellar interfacial electrostatic potential (‘I'probe), as measured by reliable acid-base indicator techniques, and the critical micelle concentration (cmc) for dodecyltrimethylammonium bromide/NaBr, dodecyltrimethylammonium chloride/NaCl, sodium dodecyl sulfate/NaCl, sodium dodecyl sulfate/NaC104, and sodium decyl sulfate/NaC104 systems has been examined. For these dilute micellar systems, it has been found that probe|/unit change in log cmc is circa 59 mV at 25. A thermodynamic treatment, appropriate for the objective of interpreting the relationship between ‘I'probe and the cmc, demonstrates that this form of behavior is consistent with ‘I' obe being equal to..