| Summary: | The structure of surfactant micellar solutions subjected to shear is of much current interest. Neutron reflection can provide information about the distribution of surfactant in the vicinity of the wall of the shear cell, and complement other scattering techniques, such as small angle neutron scattering. The construction of a shear cell for neutron reflectivity measurements is described, and some recent preliminary results on the effect of shear on the adsorption of the non-ionic surfactant, hexaethylene glycol monohexadecyl ether (C16E6), at the planar silicon/solution interface are discussed. The results provide direct evidence of shear-induced structures in the vicinity of the cell wall. At a low surfactant concentration ordered layering of the surfactant separated by solvent-rich regions, and extending into the bulk solution is observed, in addition to the adsorbed layer on the solid surface. The application of Poiseuille shear flow appears to induce a more ordered and well-defined structure at the interface.
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