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arXiv · 2401.15325

Study of the Liquid/Vapor Interfacial Properties of Concentrated Polyelectrolyte-Surfactant Mixtures Using Surface Tensiometry and Neutron Reflectometry: Equilibrium, Adsorption Kinetics and Dilational Rheology

Sara Llamas·Eduardo Guzman·Andrew Akanno·Laura Fernandez-Pena·Francisco Ortega·Richard A. Campbell·Reinhard Miller·Ramon G. Rubio
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Abstract

The adsorption of mixtures of poly(diallyldimethylammonium chloride) (PDADMAC) and sodium N-lauroyl-N-methyltaurate (SLMT) at the water / vapor interface has been studied using drop profile tensiometry and neutron reflectometry. This study sheds light on the mechanisms involved in the adsorption of polyelectrolyte-oppositely charged surfactants by the characterization of both equilibrium and dynamics features associated with the layer formation at the fluid interface. The results are discussed in terms of an adsorption-equilibration of the interfacial layers as a two-step process: the initial stages involve the adsorption of polyelectrolyte-surfactant complexes formed in the bulk, and a subsequent stage involves reorganization of the interface. This work contributes to the understanding of the physico-chemical features of systems that undergo complex bulk and interfacial interactions with importance in science and technology.

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Sara Llamas, Eduardo Guzman, Andrew Akanno, Laura Fernandez-Pena, Francisco Ortega, Richard A. Campbell, Reinhard Miller, Ramon G. Rubio. 2024-01-27. Study of the Liquid/Vapor Interfacial Properties of Concentrated Polyelectrolyte-Surfactant Mixtures Using Surface Tensiometry and Neutron Reflectometry: Equilibrium, Adsorption Kinetics and Dilational Rheology. https://doi.org/10.1021/acs.jpcc.7b12457

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