A review on emulsification via microfluidic processes

Abstract

Emulsion is a disperse system with two immiscible liquids, which demonstrates wide applications in diverse industries. Emulsification technology has advanced well with the development of microfluidic process. Compared to conventional methods, the microfluidics-based process can produce controllable droplet size and distribution. The droplet formation or breakup is the result of combined effects resulting from interfacial tension, viscous, and inertial forces as well as the forces generated due to hydrodynamic pressure and external stimuli. In the current study, typical microfluidic systems, including microchannel array, T-shape, flow-focusing, co-flowing, and membrane systems, are reviewed and the corresponding mechanisms, flow regimes, and main parameters are compared and summarized.

Graphical abstract

Keywords

microfluidics / emulsification / capillary number / droplet breakup

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Acknowledgements

This work was supported by the National Key Research and Development Program of China (Grant Nos. 2017YFB1103002 and 2018YFB0604304), Federal Ministry for Economic Affairs and Energy, Germany (No. 03ET1093C), Fundamental Research Funds for the Central Universities, China (No. 2017MS011), and the National Natural Science Foundation of China (Grant No. 51821004).

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