Influence of oil types on the formation and stability of nano-emulsions by D phase emulsification

The effect of oil types on the formation and stability of nano-emulsions by D phase emulsification method was investigated comprehensively in this paper. Three kind of oils (straight-chain alkanes, branched alkanes, and esters oils) were used and the formation of the nano-emulsions was studied. The stability of prepared nano-emulsions was characterized by the variation curve of the droplet mean diameter within 28 days. It has been found that for alkane oils, the molecular weight was important to the formation and stability of nano-emulsions. Low molecular weight alkane oil (7# mineral oil, Isododecane) formed smaller nano-emulsions (157.3 nm, 125.1 nm), but the emulsions have poor stability. For ester oils containing heteroatoms in the structure, nano-emulsions with bigger particles tended to be formed due to the better affinity of oils to glycerin. In addition, it was found that the formation and stability of nano-emulsions should be discussed separately. Temperature had different effects at different preparation processes.