Research objectives and content
Lately a dilute bicontinuous cubic phase has been discovered in a Iyotropic system consisting of surfactant, water and oil (1). Being strongly correlated, this phase shows characteristic lengths up to 2800 A. Surprisingly, the structure exists upon dilution of a microemulsion, i.e. Iiquid phase. Moreover, the liquid to solid transition seems to be continuous or only weakly discontinuous.
The stability of this phase cannot be explained by the existing description of diluted phases such as lamellar or sponge phases. The project is to improve the structural characterization of this phase and to study its dynamic properties. This will enable us to give a good description of its stability. Experimental techniques will be scattering methods (X-ray, neutrons, light), rheological measurements and frequency dependent conductivity measurements.
Training content (objective, benefit and expected impact)
The knowledge of the applicant concerning both the experimental techniques described and the physical-chemistry of complex fluids will greatly improve. This will prepare her for either an academic career or a position in industry.
Links with industry / industrial relevance (22)
The slow release of drugs is one of the current applications of cubic phases, and the structural dimension of extremely dilute cubic phases make them an interesting candidate for similar projects. However, the fundamental aspect is too recent to foresee all possible future applications.
(I) U. Peter, S. Konig, D. Roux, A.-M. Bellocq, Phys. Rev. Lett. 76, (1996) 3866 U. Peter, Diplomarbeit, Technische Universitat Munchen (1995)