Drops on soft solids: free energy and double transition of contact angles

  title={Drops on soft solids: free energy and double transition of contact angles},
  author={L. Alrik Lubbers and Joost H. Weijs and Lorenzo Botto and S Das and Bruno Andreotti and Jacco H. Snoeijer},
  journal={Journal of Fluid Mechanics},
Abstract The equilibrium shape of liquid drops on elastic substrates is determined by minimizing elastic and capillary free energies, focusing on thick incompressible substrates. The problem is governed by three length scales: the size of the drop $R$ , the molecular size $a$ and the ratio of surface tension to elastic modulus $\gamma /E$ . We show that the contact angles undergo two transitions upon changing the substrate from rigid to soft. The microscopic wetting angles deviate from Young’s… Expand
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