Highly concentrated water-in-oil gel-emulsions consisting of mixtures of hydrogenated and fluorinated gel-emulsions were prepared by two different procedures. Diffusion of a model molecule from the gelemulsion mixtures was studied and compared with those of hydrogenated and fluorinated systems. The stability of the mixed gel-emulsions was assessed and related to the diffusion coefficients. Diffusion experiments were carried out by two different methods, and diffusion coefficients were determined by numerical solution. In one experimental method the diffusion to a receptor solution was measured while in the other method the diffusion of the model molecule within the emulsion was determined. The results show that it is possible to control the stability and to obtain intermediate diffusion rates using appropriate gel-emulsion mixtures.

Financial support from CICYT (grant QUI96-0454) and from Generalitat de Catalunya (1995SGR-00498) and the CNRS/CSIC bilateral program (project no. 1933) is gratefully acknowledged. G.C. acknowledges CIRIT for financial support.

Peer reviewed