Publication
Title
Inverted micellar structure determination of zinc-di-iso-hexadecyl-sulfonate in isododecane by small angle X-ray scattering and vapour pressure lowering
Author
Abstract
Small-angle X-ray scattering (SAXS), high-precision density measurements, and vapor pressure lowering (VPL) yield information on the micellar state of the anionic surfactant ZAS (Zn(C16H33SO3)2) in isododecane. Strong evidence is found for a bimodal size distribution of the surfactant over some small aggregates (oligomers) at a concentration of 0.5-1.0 mmole/liter and larger inverted micelles. The latter display a narrow size distribution around the average aggregation number, 17, which is rather temperature and concentration independent. The inverted micelles can be described as network structures with a diffuse transition region of 5A˚between the polar core and apolar collar. The low electron density in the polar core is probably due to the presence of solvent molecules and/or apolar surfactant tails even in its center. Convincing evidence is found for an aspherical shape of the micellar core. Two geometrical forms are proposed, either an elongated cylinder (h = 32A˚, r = 8.5A˚) or a disklike particle (h = 10A˚, r = 15A˚).
Language
English
Source (journal)
Journal of colloid and interface science. - New York, N.Y.
Publication
New York, N.Y. : 1981
ISSN
0021-9797
Volume/pages
81:2(1981), p. 341-353
ISI
A1981LU66600006
Full text (Publisher's DOI)
Full text (publisher's version - intranet only)
UAntwerpen
Faculty/Department
Publication type
Subject
External links
Web of Science
Record
Identification
Creation 26.09.2013
Last edited 09.06.2017