Hohenschutz, Max and Grillo, Isabelle and Dewhurst, Charles and Schmid, Philipp and Girard, Luc and Jonchere, Alban and Diat, Olivier and Bauduin, Pierre (2021) Superchaotropic nano-ions as foam stabilizers. JOURNAL OF COLLOID AND INTERFACE SCIENCE, 603. pp. 141-147. ISSN 0021-9797, 1095-7103
Full text not available from this repository. (Request a copy)Abstract
Hypothesis: Weakly hydrated nanometric ions, called superchaotropes, were recently shown to adsorb strongly to non-ionic surfaces affecting drastically the surface's physical-chemical properties due to a charging effect. Superchaotropic ions could serve as stabilizing agents for non-ionic colloidal systems, such as non-ionic surfactant foams. Experiments: We study foams of the non-ionic surfactant BrijO10 (C18:1E10) without and in presence of the superchaotropic Keggin-ion SiW12O404 (SiW). The foams are investigated under free drainage conditions by image analysis and conductimetry to reveal the effect of SiW on the foam stability, liquid drainage, and bubble size. Additionally, small angle neutron scattering on the same foams, but in a dry quasistationary state, provides insight into effects of SiW on the foam films. Findings: SiW strongly stabilizes non-ionic surfactant foams at millimolar concentrations by inducing electrostatic repulsions between foam film interfaces resulting in thicker and monodisperse foam films. A similar effect is observed with the ionic surfactant sodium dodecylsulfate (SDS) but to a lesser extent and with a different mechanism. At the foam films' interface, SiW adsorbs to the polar non-ionic surfactant heads driven by the superchaotropic effect whereas DS anchors between non-ionic surfactant alkyl chains by the hydrophobic effect. The potential of superchaotropic ions as foam stabilizers is herein demonstrated. (C) 2021 Elsevier Inc. All rights reserved.
| Item Type: | Article |
|---|---|
| Uncontrolled Keywords: | AQUEOUS FOAMS; SURFACTANT; FILMS; PARTICLES; SYNERGISM; NEUTRON; AGGREGATION; BEHAVIOR; ORIGIN; Superchaotrope; Nano-ion; Stable foam; Foam SANS; Mixed surfactant foam |
| Subjects: | 500 Science > 540 Chemistry & allied sciences |
| Divisions: | Chemistry and Pharmacy > Institut für Anorganische Chemie > Chair Prof. Dr. Arno Pfitzner |
| Depositing User: | Dr. Gernot Deinzer |
| Date Deposited: | 14 Sep 2022 08:39 |
| Last Modified: | 14 Sep 2022 08:39 |
| URI: | https://pred.uni-regensburg.de/id/eprint/47412 |
Actions (login required)
 |
View Item |
