화학공학소재연구정보센터
Journal of Colloid and Interface Science, Vol.225, No.1, 214-218, 2000
Creaming stability of flocculated monodisperse oil-in-water emulsions
The influence of droplet flocculation on the creaming stability of monodisperse n-hexadecane oil-in-water emulsions was studied. The creaming velocity of emulsions with different droplet radii (0.43 and 0.86 mu m), droplet concentrations (1-67 vol%), and sodium dodecyl sulfate (SDS) concentrations (7-80 mM) were measured. Depletion flocculation was observed in the emulsions when the aqueous phase SDS concentration exceeded a particular level (similar to 40 mM for 0.43-mu m droplets and similar to 15 mM for 0.86-mu m droplets). Creaming was monitored by measuring the back-scattered light from an emulsion as a function of its height. The creaming velocity increased with increasing flocculation and decreased with increasing droplet concentration. These results have important implications for the formulation of emulsion-based materials.