Change search
ReferencesLink to record
Permanent link

Direct link
Effects of protonation on foaming properties of dodecyldimethylamine oxide solutions: a pH-study
KTH, School of Chemical Science and Engineering (CHE), Chemistry, Surface and Corrosion Science.
2015 (English)In: Soft Matter, ISSN 1744-683X, Vol. 11, no 3, 561-571 p.Article in journal (Refereed) Published
Abstract [en]

The critical micelle concentration (cmc), the surface excess (Gamma), as well as the micelle aggregation number (m) of the surfactant dodecyldimethylamine oxide (C(12)DMAO) have been reported to strongly depend on the pH-value of the aqueous surfactant solution. At high ionic strength, the cmc displays a minimum, while both Gamma and m have a maximum at a pH-value close to the pK(a) of the surfactant. These experimental observations have been explained as being due to specific hydrogen bonds between the head groups, which are formed once the surfactant is partly or fully protonated. This investigation addresses the question of whether the pH also affects the foaming properties of C(12)DMAO solutions. To answer this question we measured the foamability and the foam stability of C(12)DMAO solutions at a fixed C12DMAO concentration of 5 cmc for five different pH-values, namely pH = 2, 3, 5, 8, and 10. We found that the foamability is hardly affected by the pH-value, while the foam stability strongly depends on the pH. As is the case for the above mentioned properties, the foam stability also displays an extremum in the studied pH-range, namely a maximum at pH = 5. We discuss our results in terms of the hydrogen bond hypothesis and show that this hypothesis indeed is in line with the observed trend for the foam stability. Moreover, we discuss that hydrogen bond formation may rationalize how the molecular structure of a surfactant affects foam stability.

Place, publisher, year, edition, pages
2015. Vol. 11, no 3, 561-571 p.
Keyword [en]
Agglomeration, Bond strength (chemical), Critical micelle concentration, Ionic strength, Micelles, pH, Protonation, Stability, Aqueous surfactant solutions, Critical micelle concentration (cmc), Dodecyldimethylamine oxides, Foaming properties, High ionic strength, Hydrogen-bond formation, Micelle aggregation numbers, Surface excess
National Category
Chemical Sciences
URN: urn:nbn:se:kth:diva-159366DOI: 10.1039/c4sm02476aISI: 000346911600014ScopusID: 2-s2.0-84919477293OAI: diva2:785119

QC 20150202

Available from: 2015-02-02 Created: 2015-01-29 Last updated: 2015-02-02Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full textScopus

Search in DiVA

By author/editor
Claesson, Per
By organisation
Surface and Corrosion Science
In the same journal
Soft Matter
Chemical Sciences

Search outside of DiVA

GoogleGoogle Scholar
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Altmetric score

Total: 23 hits
ReferencesLink to record
Permanent link

Direct link