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arXiv · cond-mat/0611682

Capillary origami: spontaneous wrapping of a droplet with an elastic sheet

C. Py·P. Reverdy·L. Doppler·J. Bico·B. Roman·C. N. Baroud
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Abstract

The interaction between elasticity and capillarity is used to produce three dimensional structures, through the wrapping of a liquid droplet by a planar sheet. The final encapsulated 3D shape is controlled by tayloring the initial geometry of the flat membrane. A 2D model shows the evolution of open sheets to closed structures and predicts a critical length scale below which encapsulation cannot occur, which is verified experimentally. This {\it elastocapillary length} is found to depend on the thickness as $h^{3/2}$, a scaling favorable to miniaturization which suggests a new way of mass production of 3D micro- or nano-scale objects.

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C. Py, P. Reverdy, L. Doppler, J. Bico, B. Roman, C. N. Baroud. 2006-11-27. Capillary origami: spontaneous wrapping of a droplet with an elastic sheet. https://doi.org/10.1103/physrevlett.98.156103

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