HYDRAULIC FLUIDS BASED ON WATER-IN-OIL MICROEMULSIONS

Hydraulic fluids based on water-in-oil microemulsions and nonionic emulsifiers were prepared. Phase diagrams of the micro-emulsions were constructed with the intention of using the most suitable of them for formulation of hydraulic fluid with and without additives. Up to 22 wt% of water could be solubilized when a carefully designed mixture of nonionic ethoxylated alcohols was employed as the surfactant and up to nearly 35 wt% of water could be solubilized when a mixture of paraffinic oil and pentanol was used as the oil phase and the same mixture of nonionic ethoxylated alcohols was employed as the surfactant. Droplet size, stability, and other physical characteristics were evaluated.