Binary Phase Diagram of Water/Brij58 Studied by SAXS |
| S. Fall, B. Pattier, L. Benyayia and A. Gibaud
Laboratoire de Physique de l'Etat Condensé, UMR CNRS 6087, Université du Maine, 72085 Le Mans Cedex 09, France |
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| The phase diagram of the binary water/Brij58 system has been studied at constant temperature T = 20°C first by simple optical observation and then by small angle X-ray scattering. The small angle X-ray scattering patterns in the isotropic diluted phase are analyzed in a quantitative way by refining the experimental measurements with a model assuming hard spherical micelles in interaction. The micelles are described by a poly dispersed core-shell model and the interaction by the Perkus-Yevick hard-sphere model. The fitted parameters are analyzed in detail to determine the way poly-oxy-ethylene blocks are hydrated with respect to the volumic fraction of water. In the more concentrated regime, the crystalline phases that are identified are the Fm3m cubic, the 2D hexagonal and the lamellar phases. The structural parameters that describe each phases are analyzed and commented. The small angle X-ray scattering study is complemented by the determination of the temperature dependent liquid-solid transition by rheology. |
| DOI: 10.12693/APhysPolA.121.388 PACS numbers: 81.30.-t, 61.05.C-, 64.70.dg |