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arXiv · 2504.09267

Controlling Droplets at the Tips of Fibers

Mengfei He·Samay Hulikal·Marianna Marquardt·Hao Jiang·Anupam Pandey·Teng Zhang·Christian D. Santangelo·Joseph D. Paulsen
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Abstract

Many complex wetting behaviors of fibrous materials are rooted in the behaviors of individual droplets attached to pairs of fibers. Here, we study the splitting of a droplet held between the tips of two cylindrical fibers. We discover a sharp transition between two post-rupture states, navigated by changing the angle between the rods, in agreement with our bifurcation analysis. Depinning of the bridge contact line can lead to a much larger asymmetry between the volume of liquid left on each rod. This second scenario enables the near-complete transfer of an aqueous glycerol droplet between two identical vinylpolysiloxane fibers. We leverage this response in a device that uses a ruck to pass a droplet along a train of fibers, a proof-of-concept for the geometric control of droplets on deformable, architected surfaces.

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Mengfei He, Samay Hulikal, Marianna Marquardt, Hao Jiang, Anupam Pandey, Teng Zhang, Christian D. Santangelo, Joseph D. Paulsen. 2025-04-12. Controlling Droplets at the Tips of Fibers. https://doi.org/10.1103/43cy-32wf

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