Influence of Creaming and Ripening on the Aggregation Rate of Non-Ionic Dodecane-in-Water Nanoemulsions

Abstract

The possible influence of creaming during the measurement of the aggregation rate of dodecane-in-water nanoemul- sions stabilized with Brij 30 is explored. For this purpose additional emulsions made with a neutral-buoyancy oil (bro- mo-dodecane) and mixtures of dodecane and Br-dodecane with squalene were synthesized. It is concluded that when the effect of ripening is suppressed, the influence of buoyancy on the evaluation of the flocculation rate is negligible. In the absence of squalene, ripening is present, and a sizeable difference in the flocculation rate of dodecane and bro- mo-dodecane is observed. However, this difference is not caused by the effect of gravity.