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arXiv · 1402.0262

How a Blister Heals

Jonathan E. Longley·L. Mahadevan·Manoj K. Chaudhury
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Abstract

We use experiments to study the dynamics of the healing of a blister, a localized bump in a thin elastic layer that is adhered to a soft substrate everywhere except at the bump. We create a blister by gently placing a glass cover slip on a PDMS substrate. The pressure jump across the elastic layer drives fluid flow through micro-channels that form at the interface between the layer and the substrate; these channels coalesce at discrete locations as the blister heals and eventually disappear at a lower critical radius. The spacing of the channel follows a simple scaling law that can be theoretically justified, and the kinetics of healing is rate limited by fluid flow, but with a non-trivial dependence on the substrate thickness that likely arises due to channelization. Our study is relevant to a variety of soft adhesion scenarios.

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Jonathan E. Longley, L. Mahadevan, Manoj K. Chaudhury. 2014-02-02. How a Blister Heals. https://doi.org/10.1209/0295-5075%2F104%2F46002

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