Abstract
Using self-foaming dispenser, wet aqueous foams were prepared from isoviscous solutions of sodium lauryl sulfate (SLS) with chemically distinct polymer stabilizers. Contribution of coalescence and Ostwald ripening to the foam decay was examined from photos and video data. The bubble coarsening was estimated by dispersion analysis using the Lifshitz–Slezov–Wagner equation. Water-soluble polymers were selected from typical thickeners and suspending agents. Xanthan gum, hydroxyethyl cellulose, polyacrylamide, cross-linked sodium polyacrylate, cross-linked and hydrophobically modified (meth)acrylate copolymers were tried as foam stabilizers. By the same way, xanthan gum and submicron bentonite particles were used as foam stabilizers. Stability of the foams containing mentioned polymers as well as xanthan plus bentonite studied by the photographs and dispersion analysis. The polymers characterize by their efficacy to stabilize the wet foam. Possible reasons for poor stabilization of the foam containing cross-linked polyacrylates, both hydrophilic and hydrophobically modified, are given. The behavior of polymer-containing foams and joint stabilizing action of xanthan and bentonite are explained by variations in the structure of foam films.
Graphical Abstract
Disclosure statement
All authors declare that they have no conflict of interest in the publication of this manuscript.