Equilibration in a geranyl acetate emulsion

Water and a geranyl acetate solution of a non-ionic surfactant, a commercial C12EO4, were brought into contact in amounts to give a combination of a lamellar liquid crystal and an oil phase of equal weights at equilibrium and the equilibration transport between the layers was followed by measuring the change in layer heights with time. The initial reaction, lasting approximately two months, transferred surfactant from the oil phase to combine with water to form a birefringent layer initially containing excess water over the fraction in the liquid crystal in equilibrium with both water and oil phase. After this period the composition of the oil phase had reached a level corresponding to equilibrium with both water and a lamellar liquid crystal, while the birefringent phase, although a liquid crystal, still contained less water fraction than required for equilibrium. The final equilibration process of transferring the excess water to the formed liquid crystal was extremely slow with an estimated time to reach equilibrium of several years.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideResearch highlights▶ Evaporation of emulsions. ▶ Deviations from equilibrium conditions. ▶ Determining the growth and reduction of the phase volumes. ▶ Slow inclusion of compounds into solid and liquid crystal. ▶ Evaluation was done of the behavior of emulsion after application on solid surface.