Amphiphilic Molecules in Lyotropic Liquid Crystals and Micellar Phases

Abstract

The behaviour of the paraffinic chains of amphiphilic molecules such as soaps, detergents and lipids, in aggregates of the liquid crystalline and micellar phases has been studied in detail with NMR. These studies demonstrated the dynamical disorder of the chains, particularly that introduced by the conformation changes of their carbon-carbon skeleton. In the most studied case, that of the lamellar phases with flat amphiphile/water interfaces, they also gave direct access to the disorder profile of a chain, making possible a description of its anisotropic behaviour around the local normal to the interface. A very limited number of studies only has been devoted to hexagonal and micellar phases, with cylindrical and spherical interfaces, where one might expect, on purely intuitive grounds, important changes in the disorder profile imposed by the curvatures of the interfaces.