Additional support for a revised Gibbs analysis
Gibbs-determined areas of >60 A(2)/molecule for many common surfactants cause rather small surface tension reductions when measured on a Langmuir film balance. This is inconsistent with an air/water interface being saturated throughout the steep linear decline in plots of surface tension versus l...
Veröffentlicht in: | Langmuir : the ACS journal of surfaces and colloids. - 1992. - 26(2010), 3 vom: 02. Feb., Seite 1588-9 |
---|---|
1. Verfasser: | |
Weitere Verfasser: | , |
Format: | Online-Aufsatz |
Sprache: | English |
Veröffentlicht: |
2010
|
Zugriff auf das übergeordnete Werk: | Langmuir : the ACS journal of surfaces and colloids |
Schlagworte: | Journal Article |
Zusammenfassung: | Gibbs-determined areas of >60 A(2)/molecule for many common surfactants cause rather small surface tension reductions when measured on a Langmuir film balance. This is inconsistent with an air/water interface being saturated throughout the steep linear decline in plots of surface tension versus ln [surfactant]. In support for a gradually populating interface in the linear region, we have found that sodium docosanyl sulfate lowers the surface tension by only 7 mN/m when compressed to 50 A(2)/molecule. When docosanyltrimethylmmonium bromide is compressed to 65 A(2)/molecule, the surface tension is lowered about 15 mN/m as compared to a 30-40 mN/m drop occurring within the range of typical Gibbs analysis. Saturation of the interface is often obscured by competitive micelle formation that levels the surface tension versus ln [surfactant] plot before saturation has a chance to do so |
---|---|
Beschreibung: | Date Completed 24.03.2010 Date Revised 24.02.2014 published: Print CommentIn: Langmuir. 2011 Jun 21;27(12):7958-62; discussion 7963-5. - PMID 21604731 Citation Status PubMed-not-MEDLINE |
ISSN: | 1520-5827 |
DOI: | 10.1021/la9043914 |