Self-crumpling elastomers: bending induced by the drying stimulus of a nanoparticle suspension

François Boulogne; Howard A. Stone

doi:10.1209/0295-5075/108/19001

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arXiv · 1409.6934

Self-crumpling elastomers: bending induced by the drying stimulus of a nanoparticle suspension

François Boulogne·Howard A. Stone

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Abstract

We report an experimental study of the drying-induced peeling of a bilayer, consisting of an elastomeric disk coated with a suspension of nanoparticles. We show that although capillary forces associated with the scale of the droplet can not compete with the adhesion of the elastomer on a surface, nevertheless large tensile stresses develop in the coating, which results in a moment bending the bilayer. We attribute this stress to the nano-menisci in the pores of the colloidal material and we propose a model that describes successfully the early stage curvature of the bilayer. Thus, we show that the peeling can be conveniently controlled by the particle size and the coating thickness.

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François Boulogne, Howard A. Stone. 2014-09-24. Self-crumpling elastomers: bending induced by the drying stimulus of a nanoparticle suspension. https://doi.org/10.1209/0295-5075%2F108%2F19001

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