Issue
EPL
Volume 77, Number 4, February 2007
Article Number 44005
Number of page(s) 5
Section Electromagnetism, Optics, Acoustics, Heat Transfer, Classical Mechanics, and Fluid Dynamics
DOI http://dx.doi.org/10.1209/0295-5075/77/44005
Published online 09 February 2007
EPL, 77 (2007) 44005
DOI: 10.1209/0295-5075/77/44005

3D aggregation of wet fibers

C. Py1, R. Bastien1, J. Bico1, B. Roman1 and A. Boudaoud2

1  Physique et Mécanique des Milieux Hétérogènes, UMR 7636 CNRS - ESPCI - Paris 6 - Paris 7, 10 rue Vauquelin 75005 Paris, France
2  Laboratoire de Physique Statistique, UMR 8550 CNRS ENS - 24 rue Lhomond 75005 Paris, France


received 28 August 2006; accepted in final form 19 December 2006; published February 2007
published online 9 February 2007

Abstract
Wet fibrous structures such as nanotube carpets or macroscopic brushes tend to self-assemble into bundles when the liquid evaporates. The aggregation process relies on a balance between capillary attraction provided by liquid bridges and restoring torque due to structure stiffness. The final self-organized structure is found to result from a cascade of pairing of smaller bundles into bigger ones. We first describe, both experimentally at a macroscopic scale and theoretically, the case of a single pair of fibers and then generalize this description to more complex 3D assemblies. We finally show the relevance of our results to micro-scale experiments from the literature.

PACS
46.32.+x - Static buckling and instability.
47.55.nk - Liquid bridges.
81.16.Dn - Self-assembly.

© Europhysics Letters Association 2007