P. Sharbati, A.K. Kota
North Carolina State University,
United States
Keywords: hyperelastic surfaces, coating delamination, superomniphobicity
Summary:
One of the key challenges in developing stretchable superomniphobic surfaces is preventing coating delamination under mechanical strain. Here, we report hyperelastic superomniphobic surfaces engineered to retain their repellency without delamination, even at 400% strain and after thousands of stretch–release cycles. To achieve such hyperelastic superomniphobic surfaces, we introduce a novel design– an array of discrete micro protrusions on the hyperelastic material that redistribute the stresses out-of-plane during elongation. Such an out-of-plane redistribution of stresses results in nearly stress-free tops of the microprotrusions, allowing the coating to be virtually intact even after 5000 stretch release cycles. Furthermore, through systematic experiments and theoretical analysis, we studied the influence of elongation on contact angles, sliding angles and breakthrough pressures on our hyperelastic superomniphobic surfaces. We envision that our robust hyperelastic superomniphobic surfaces will have a wide range of applications in wearable electronics, textiles, artificial skins, droplet manipulation and protective wraps.