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Induced Crystallization of Polyelectrolyte-Surfactant Complexes at the Gas-Water Interface

D. Vaknin·S. Dahlke·A. Travesset·G. Nizri·S. Magdassi
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Abstract

Synchrotron-X-ray and surface tension studies of a strong polyelectrolyte (PE) in the semi-dilute regime (~ 0.1M monomer-charges) with varying surfactant concentrations show that minute surfactant concentrations induce the formation of a PE-surfactant complex at the gas/solution interface. X-ray reflectivity and grazing angle X-ray diffraction (GIXD) provide detailed information of the top most layer, where it is found that the surfactant forms a two-dimensional liquid-like monolayer, with a noticeable disruption of the structure of water at the interface. With the addition of salt (NaCl) columnar-crystals with distorted-hexagonal symmetry are formed.

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D. Vaknin, S. Dahlke, A. Travesset, G. Nizri, S. Magdassi. 2004-01-12. Induced Crystallization of Polyelectrolyte-Surfactant Complexes at the Gas-Water Interface. https://doi.org/10.1103/physrevlett.93.218302

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