Eur. Phys. J. E (2007) 22: 157-161
https://doi.org/10.1140/epje/e2007-00021-2

Regular Articles

Hydrodynamic effects in bicontinuous microemulsions measured by inelastic neutron scattering

¹ Institut für Festkörperforschung, Forschungszentrum Jülich GmbH, 52425, Jülich, Germany
² Institut Laue Langevin, BP 156, Grenoble, 38042, Grenoble Cedex 9, France

^* e-mail: o.holderer@fz-juelich.de

Received: 22 November 2006
Published online: 14 March 2007

Abstract

The dynamical properties of bicontinuous microemulsions have been studied with neutron spin echo spectroscopy around length scales corresponding to the correlation peak q₀. Comparison of samples with different contrasts for neutrons shed light on the two modes dominated either by variation of the oil/water difference or surfactant concentration in the hydrodynamic regime. The results have been compared to theoretical predictions of the relaxation rates of bicontinuous microemulsions by Nonomura and Ohta [M. Nonomura, T. Ohta, J. Chem. Phys. 110, 7516 (1999)]. The influence of modification of the surfactant layer bending constants in the microemulsion by addition of homopolymers (polyethylenepropylene: PEP_X and polyethyleneoxide: PEO_X, X=5 kg/mol), dissolved in the oil phase and water, has been investigated.