Elastometry of deflated capsules: elastic moduli from shape and wrinkle analysis.

  title={Elastometry of deflated capsules: elastic moduli from shape and wrinkle analysis.},
  author={Sebastian Knoche and Dominic Vella and Elodie Aumaitre and Patrick Degen and Heinz Rehage and Pietro Cicuta and Jan Kierfeld},
  journal={Langmuir : the ACS journal of surfaces and colloids},
  volume={29 40},
Elastic capsules, prepared from droplets or bubbles attached to a capillary (as in a pendant drop tensiometer), can be deflated by suction through the capillary. We study this deflation and show that a combined analysis of the shape and wrinkling characteristics enables us to determine the elastic properties in situ. Shape contours are analyzed and fitted using shape equations derived from nonlinear membrane-shell theory to give the elastic modulus, Poisson ratio and stress distribution of the… 

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