Microfluidic Exploration of the Phase Diagram of a Surfactant/Water Binary System

Jacques Leng; Mathieu Joanicot; Armand Ajdari

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Microfluidic Exploration of the Phase Diagram of a Surfactant/Water Binary System

Jacques Leng·Mathieu Joanicot·Armand Ajdari

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Abstract

We investigate the behaviour of a binary surfactant solution (AOT/water) as it is progressively concentrated in microfluidic evaporators. We observe in time a succession of phase transitions from a dilute solution up to a dense state, which eventually grows and invades the microchannels. Analyzing these observations, we show that, with a few experiments and a limited amount of material, our microdevices permit a semi-quantitative screening of the equilibrium phase diagram as well as a few kinetic observations.

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Jacques Leng, Mathieu Joanicot, Armand Ajdari. 2006-10-31. Microfluidic Exploration of the Phase Diagram of a Surfactant/Water Binary System. https://arxiv.org/abs/cond-mat/0610876

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