Double-Emulsion Drop Evaporation and Formation of a Daughter Droplet

Langmuir. 2019 Mar 26;35(12):4403-4411. doi: 10.1021/acs.langmuir.8b03862. Epub 2019 Mar 7.

Abstract

In this study, we present experimental and theoretical analyses of evaporating a double-emulsion drop resting on a substrate. Multistage evaporation of the outer and inner droplet is witnessed. The complete evaporation of the outer drop and the initialization of the inner drop evaporation demonstrate an interesting transition dynamics. After the apparent completion of evaporation of the inner phase of a double-emulsion drop, surprisingly, formation of a daughter droplet is observed. We further investigated to hypothesize this phenomenon and achieved the formation of the daughter droplet for a single-phase drop as well. While engineering the "daughter drop formation" phenomena, we also proposed a way to obtain prolonged fixed contact line evaporation for a single-phase drop.