Adsorption of MultiLamellar tubes with a temperature tunable diameter at the air-water interface: a process driven by the bulk properties

François Boué (1) , Anne-Laure Fameau (1, 2) , Jean-Paul Douliez (2) , Frédéric Ott (1) , Bruno Novales (2) , Fabrice Cousin (1)

1 LLB - UMR 12 - Laboratoire Léon Brillouin
2 BIA - Unité de recherche sur les Biopolymères, Interactions Assemblages

The behavior at the air/water interface of multilamellar tubes made of the ethanolamine salt of the 12-hydroxy stearic acid as a function of the temperature has been investigated using Neutron Reflectivity. Those tubes are known to exhibit a temperature tunable diameter in the bulk. We have observed multilamellar tubes adsorbed at the air/water interface by specular neutron reflectivity. Interestingly, at the interface, the adsorbed tubes exhibit the same behavior than in the bulk upon heating. There is however a peculiar behavior at around 50°C for which the increase of the diameter of the tubes at the interface yields an unfolding of those tubes into a multilamellar layer. Upon further heating, the tubes re-fold and their diameter re-decrease after what they melt as observed in the bulk. All structural transitions at the interface are nevertheless shown to be quasi-completely reversible. This provides to the system a high interest for its interfacial properties because the structure at the air/water interface can be tuned easily by the temperature.

Domaines: Matière Molle [cond-mat.soft]

François Boué, Anne-Laure Fameau, Jean-Paul Douliez, Frédéric Ott, Bruno Novales, et al.. Adsorption of MultiLamellar tubes with a temperature tunable diameter at the air-water interface: a process driven by the bulk properties. Journal of Colloid and Interface Science, 2011, 362 (2), pp.397-405. ⟨10.1016/j.jcis.2011.06.080⟩. ⟨hal-00737510⟩