Phase separation bursting and symmetry breaking inside an evaporating droplet; formation of a flower-like pattern

Vahid Nasirimarekani

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arXiv · 2409.07095

Phase separation bursting and symmetry breaking inside an evaporating droplet; formation of a flower-like pattern

Vahid Nasirimarekani

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Abstract

Pattern formation inside a liquid phase is a phenomenon involved in many different aspects of life on our planet. The droplet form of a liquid that evaporates can reveal patterns that depend on the chemistry of the droplet and the physical parameters involved. We observed a flower-like deposition pattern of micrometer-sized particles as a result of the evaporation of a droplet containing salt and a non-ionic polymer. We show experimentally that the phase separation of the polymer due to the salting-out effect causes a strong entropic flow, which manifests as vortices. The flow is called phase separation bursting flow, which leads to the axial symmetry breaking and the formation of a radially aligned flower-like pattern. We foresee that understanding the observed flow can provide insights into the fluid physics aspects of phase separation and may have implications for technical applications.

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Vahid Nasirimarekani. 2024-09-11. Phase separation bursting and symmetry breaking inside an evaporating droplet; formation of a flower-like pattern. https://arxiv.org/abs/2409.07095

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