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Folding surfaces: Capillary Origami

It seems obvious that something which is "hydro" - "phobic" would fear water, but what happens when a thin sheet of Teflon - the most hydrophobic material that chemistry can create - touches a droplet of water?

Spontaneous wrapping of a droplet of water by Teflon (L. Gao and T.J. McCarthy, Langmuir 24 (17) 2009) is a form of Capillary Origami.

Even Teflon prefers to cling to the surface of water rather than remain in contact with air unless we make that surface superhydrophobic (see lower image sequence below).

Publications

L. Gao and T.J. McCarthy,
Teflon is Hydrophilic. Comments on Definitions of Hydrophobic, Shear versus Tensile Hydrophobicity, and Wettability Characterization,
Langmuir 24 (17) (2009) 9183-9188. View abstract

G. McHale,
All solids, including teflon, are hydrophilic (to some extent), but some have roughness induced hydrophobic tendencies,
Langmuir 25 (13) (2009) 7185-7187. Via ACS server

N.R. Geraldi, F.F. Ouali, R.H. Morris, G. McHale and M.I. Newton,
Capillary origami and superhydrophobic membrane surfaces,
Appl. Phys. Lett. 102 (21) (2013) art. 214104. View reprint