Jump to main content
Jump to site search

Issue 28, 2019
Previous Article Next Article

Precise morphology control and fast merging of a complex multi-emulsion system: the effects of AC electric fields

Author affiliations

Abstract

We showed that an AC electric field can be effectively used to control the full morphology of a multi-emulsion system (oil/water/oil, O/W/O and water/oil/water, W/O/W); specifically, the size of outer droplets and the number of inner droplets (from 5 to 0) could be controlled. In our system, such control was achieved by adopting non-contact type of electrodes together with double-flow-focusing geometry to apply an AC electric field during the formation of complex droplets. As such, the AC electric field could be used without contamination. In addition to morphology control, we also achieved both one-step and two-step merging of the core droplets in the W/O/W droplet system within 100 milliseconds, which is by far the fastest merging in double emulsion droplets ever reported. To the best of our knowledge, this paper is the first article to report the control of core droplets in an O/W/O system by matching the frequency of the AC electric field with that of the core production rate. In this article, we adopted the electric capillary number CaE to analyze the effectiveness of the AC electric field applied at a high frequency, which offers a guideline for practical applications. Furthermore, the merging phenomena among various droplet systems discovered could add extra dimensions for the manipulation of double emulsions. Our findings reveal new physical insights that bring about a better understanding of the interfacial phenomena and electrohydrodynamics of droplets, which is of great importance for practical applications involving the complex interactions of multiple droplets.

Graphical abstract: Precise morphology control and fast merging of a complex multi-emulsion system: the effects of AC electric fields

Back to tab navigation

Supplementary files

Article information


Submitted
28 Feb 2019
Accepted
21 May 2019
First published
22 May 2019

Soft Matter, 2019,15, 5614-5625
Article type
Paper

Precise morphology control and fast merging of a complex multi-emulsion system: the effects of AC electric fields

Y. Huang, S. Yin, W. H. Chong, T. N. Wong and K. T. Ooi, Soft Matter, 2019, 15, 5614
DOI: 10.1039/C9SM00430K

Social activity

Search articles by author

Spotlight

Advertisements