Change search
ReferencesLink to record
Permanent link

Direct link
Interactions between nonpolar surfaces coated with the nonionic surfactant hexaoxyethylene dodecyl Ether C12E6 and the origin of surface charges at the air/water interface
KTH, Superseded Departments, Chemistry.
2004 (English)In: Langmuir, ISSN 0743-7463, E-ISSN 1520-5827, Vol. 20, no 12, 4977-4988 p.Article in journal (Refereed) Published
Abstract [en]

The interactions between nonpolar surfaces coated with the nonionic surfactant hexaoxyethylene dodecyl ether C12E6 were investigated using two techniques and three different types of surfaces. As nonpolar surfaces, the air/water interface, silanated negatively charged glass, and thiolated uncharged gold surfaces were chosen. The interactions between the air/water interfaces were measured with a thin film pressure balance in terms of disjoining pressure as a function of film thickness. The interactions between the solid/liquid interfaces were determined using a bimorph surface force apparatus. The influence of the nature of the surface on the interaction forces was investigated at surfactant concentrations below and above the cmc. The adsorption of the nonionic surfactant on the uncharged thiolated surface does not, as expected, lead to any buildup of a surface charge. On the other hand, adsorption of C12E6 on the charged silanated glass and the charged air/water interface results in a lowering of the surface charge density. The reduction of the surface charge density on the silanated glass surfaces is rationalized by changes in the dielectric permittivity around the charged silanol groups. The reason for the surface charge observed at the air/water interface as well as its decrease with increasing surfactant concentration is discussed and a new mechanism for generation of OH- ions at this particular interface is proposed.

Place, publisher, year, edition, pages
2004. Vol. 20, no 12, 4977-4988 p.
Keyword [en]
sum-frequency spectroscopy, poly(ethylene oxide) surfactants, range hydrophobic interactions, double-layer interactions, foam films, long-range, disjoining pressures, neutron reflection, force measurements, mica surfaces
URN: urn:nbn:se:kth:diva-23478DOI: 10.1021/la.0304060ISI: 000221846000030ScopusID: 2-s2.0-2942724691OAI: diva2:342176
QC 20100525Available from: 2010-08-10 Created: 2010-08-10Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full textScopus

Search in DiVA

By author/editor
Claesson, Per M.
By organisation
In the same journal

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: 14 hits
ReferencesLink to record
Permanent link

Direct link