We had observed that the size of the inner water drop depends on the concentration of PEG initially dispersed in 1-octanol (see above figure ). We expected that it should also depend on the concentration of PVA in the continuous water phase. In fact, water diffusion within 1octanol ends when osmotic pressures are equilibrated between the internal PEG-rich water droplet and the outer continuous aqueous PVA phase (the shell of octanol thus acting as a membrane). Therefore, increasing the polymer concentration in oil induces more diffusion, and must be a way to control the internal droplet size. A direct consequence of such a water transfer towards the oil is also that the volume fraction of the continuous phase (water and PVA) decreases, while the one of the dispersed phase (octanol, with its internal water droplet) increases. For any emulsion, its viscosity is strongly dependent on the volume fraction of the different phases, especially when the amount of dispersed phase is higher than 50%. The Krieger-Dougherty law states that the relative viscosity (dispersion viscosity divided by the continuous phase viscosity) only depends on the volume fraction of the dispersed phase .