Buckling and snapping of a thin polymeric membrane exposed to a solvent drop

Abstract

We report the behavior of a thin and flat rectangular polymeric membrane, fixed at both ends, in contact with a solvent droplet. Depending on the solvent type and volume, and membrane thickness, three different regimes —no buckling, buckling, and snapping— are observed. Our study reveals that the behavior depends on the solubility parameter of the solvent and the ratio of the sum of swelling-induced force and capillary force to the elastic restoring force, i.e., the force ratio. We attempt to explain the phenomenon using the poroelastic and elastic recoil timescales. Using correlations from simple scaling, our model can estimate the maximum force ratio in terms of known quantities and predict the operating regime and maximum deflection. We expect our study will find significance in the design and analysis of systems involving flexible microbeams.

Transient deformation and swelling of paper by aqueous co-solvent solutions

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Surface acoustic wave-based generation and transfer of droplets onto wettable substrates

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