Effect of degassing on the formation and stability of surfactant-free emulsions and fine teflon dispersions

The results reported here demonstrate that the formation of surfactant-free, oil-in-water emulsions is significantly enhanced by the almost complete removal of dissolved gases. However, in an apparent contradiction, the reintroduction of dissolved gases does not destabilize already formed emulsions. Removal of dissolved gases enables the formation of much more turbid and stable hydrocarbon oil in water emulsions, which can be further studied without the effects of various additives, often needed as stabilizers. The observations reported here suggest that the dispersion of oil droplets in water is opposed by an attractive, hydrophobic force, which is dependent on the presence of dissolved gas. However, once formed, the stability of the emulsions appeared to be unaffected by any attractive hydrophobic force, in either gassed or degassed conditions. Degassing was also found to enhance the dispersion of fine Teflon particles in water.