Volume 4, Number 3, p. 174–178
SAXS and freeze-fracture studies of a lamellar tenside-water system in a shear cell during thermal treatment
G. Fetter and A. Bóta
Department of Physical Chemistry, Budapest University of Technology and Economics, H-1521 Budapest, Hungary
The layer structure and domain formation of a surfactant/water system were studied by using small angle X-ray scattering and freeze-fracture in steady and sheared states. The investigations were carried out in a shear cell constructed in two variants, for small angle X-ray scattering and for freeze-fracture, at 20 °C (lamellar structure) and 80 °C (above the melting point, ~ 55 °C), corresponding to the liquid crystalline and the liquid (reverse micellar) phases respectively. Shear drastically affected the structures below the melting point, and a complex (thermal and shear) dependence on prehistory could be observed for the structural as well as the morphological behaviour. The results demonstrate the inadequacy of the slip plane model previously introduced to characterize such systems.
Keywords: layer structure, Synperonic A7, temperature program, tenside