Author, as appears in the article.: Mackie, A.D. García Daza, F.A.
Department: Enginyeria Química
Keywords: critical micelle concentration kinetic effects coarse−grained gemini surfactants
Abstract: Experimental measurements for a variety of surfactants unexpectedly show that the critical micelle concentration (CMC) becomes constant with respect to increasing the size of the hydrophobic tail. This observation disagrees with theoretical models where it is expected to continue to decrease exponentially. Because of the lack of a satisfactory explanation for such a discrepancy from theory, we have studied these systems using a coarse-grained model within the single-chain mean field (SCMF) theory combined with relevant micellar kinetic effects. In particular, a microscopic model for poly(ethylene oxide) alkyl ether was applied to describe a series of nonionic gemini surfactants. When kinetic effects are used to correct the equilibrium CMC values from the SCMF scheme together with the loss of surfactants due to adsorption on the experimental recipient, it is possible to reproduce the correct order of magnitude of the experimental CMC results. Hence it appears that the experimental values disagree with the theoretical predictions because they are not true equilibrium values due to the fact that the time scales for these low CMC values become astronomically large.
licence for use: https://creativecommons.org/licenses/by/3.0/es/
ISSN: 0022-3654
Last page: 2032
Journal volume: 5
Papper version: info:eu-repo/semantics/acceptedVersion
Licence document URL: https://repositori.urv.cat/ca/proteccio-de-dades/
Entity: Universitat Rovira i Virgili.
Journal publication year: 2014
First page: 2027
Repositori URV