Review On "New Gels For Mixing Immiscible Liquids."

Porous materials that have a single connected pore space are used widely in filtration, separation, and chemical processing. The problem is that these materials can only handle one liquid at a time. In order to have more than one liquid, it would be more useful to have a porous material that has two continuously connected spaces that are separated from one another. In Philippe Poulin's article, "New Gels for Mixing Immiscible Liquids," he discusses results as reported by Stratford et al. at the University of Edinburgh of such a material. These results show how numerical simulations were used to analyze a bi-continuous gel system that could accomplish the goal of producing a material with these capabilities. Theoretically, two fluids are allowed to undergo phase separation, which would create two connected porous spaces. This separation, which normally would continue unhindered toward more coarse structures, is stopped by adding small particles that create stagnation in the structure, preventing it from growing.

By using computer stimulations, Stratford et al. have made their claim more cogent. The simulated results present a challenge to experimentalists to create these and other doubly compartmented structures in the laboratory. The main difficulty here will be finding particles and fluids which can be used to achieve the neutral or almost neutral wetting conditions. At the University of Hull, Binks and colleagues are already underway and have shown that by controlling the wettability of particles at the interface between two fluids, various kinds of emulsion droplets can be stabilized.

Poulin, Philippe. "New Gels For Mixing Immiscible Liquids." Science 309 (2005): 2174-2175.