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Wrinkling of a bilayer membrane

A. Concha·J. W. McIver III·P. Mellado·D. Clarke·O. Tchernyshyov·R. L. Leheny
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Abstract

The buckling of elastic bodies is a common phenomenon in the mechanics of solids. Wrinkling of membranes can often be interpreted as buckling under constraints that prohibit large amplitude deformation. We present a combination of analytic calculations, experiments, and simulations to understand wrinkling patterns generated in a bilayer membrane. The model membrane is composed of a flexible spherical shell that is under tension and that is circumscribed by a stiff, essentially incompressible strip with bending modulus B. When the tension is reduced sufficiently to a value σ, the strip forms wrinkles with a uniform wavelength found theoretically and experimentally to be λ= 2π(B/σ)^{1/3}. Defects in this pattern appear for rapid changes in tension. Comparison between experiment and simulation further shows that, with larger reduction of tension, a second generation of wrinkles with longer wavelength appears only when B is sufficiently small.

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A. Concha, J. W. McIver III, P. Mellado, D. Clarke, O. Tchernyshyov, R. L. Leheny. 2006-11-20. Wrinkling of a bilayer membrane. https://doi.org/10.1103/physreve.75.016609

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