C. Duprat and S. Protière, Capillary stretching of fibers, EPL 111 (2015)
C. Duprat, A. D. Bick, P. B. Warren and H. A. Stone, Evaporation of Drops on Two Parallel Fibers: Influence of the Liquid Morphology and Fiber Elasticity, Langmuir 29 (2013)
ANR Déformations de milieux fibreux hygroscopiques (DeFHy)
Fibrous media are functional and versatile materials, as demonstrated by their ubiquity both in natural and engineered systems. They offer benefits in filtration, insulation, wetting, water retention and coloring. Current research deals with “smart” textiles that respond to external stimuli (e.g. a change in humidity or temperature).
Within this context, we study the wetting and drying of fibrous materials, in particular in the case where the individual fibers composing the material are flexible. Elastic fibers can deform under the capillary forces arising at air-liquid interfaces. This elastocapillarity phenomenon is for example responsible of the apparent shrinkage of fibrous filters upon drying. Elastocapillary effects can also affect the liquid holding capacities of the textile, or its drying rate, as the liquid distribution within the fiber array is modified. Indeed, when deposited on a fiber array, liquid is distributed either in the form of long liquid columns or semi-spherical compact droplets, depending upon the structure of the array (i.e., the distance between the fibers) and its elasticity. In particular, we show that the liquid morphology can be controlled by adjusting the tension within the fibers. These results may be extended to tune (actively or passively) drying rate or to optimize liquid capture on fiber arrays .