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Hyperelastic superomniphobic surfaces via microprotrusion-induced stress redistribution
Mohammad Javad Zarei1, Sreekiran Pillai1, Omar Eldaly1
1Department of Mechanical and Aerospace Engineering, North Carolina State University, Raleigh, NC 27695, USA. akota2@ncsu.edu.
Materials Horizons
|August 1, 2025
Summary
Researchers developed durable superomniphobic surfaces that maintain water and oil repellency even under extreme stretching. This innovation uses microprotrusions to prevent coating damage, enabling applications in flexible electronics and textiles.
Area of Science:
- Materials Science
- Surface Science
- Nanotechnology
Background:
- Superomniphobic surfaces repel both water and oil.
- Maintaining superomniphobicity under mechanical stress, especially stretching, is a significant challenge.
- Existing superhydrophobic/superomniphobic surfaces often delaminate or lose functionality upon deformation.
Purpose of the Study:
- To engineer hyperelastic superomniphobic surfaces with unprecedented durability under high strain.
- To investigate the mechanism behind stress redistribution in stretched superomniphobic materials.
- To analyze the impact of elongation on key surface properties like contact angles and breakthrough pressures.
Main Methods:
- Fabrication of hyperelastic materials with arrays of discrete microprotrusions.
- Coating microprotrusions to achieve superomniphobicity.
- Mechanical testing involving up to 400% strain and thousands of stretch-release cycles.
- Contact angle, sliding angle, and breakthrough pressure measurements under varying strain.
Main Results:
- Achieved stable superomniphobicity at 400% strain without coating delamination.
- Demonstrated retention of superomniphobicity after 5000 stretch-release cycles.
- Identified out-of-plane stress redistribution by microprotrusions as the key mechanism for durability.
- Quantified the influence of elongation on surface wettability and barrier properties.
Conclusions:
- Novel microprotrusion design enables robust and hyperelastic superomniphobic surfaces.
- The developed surfaces exhibit exceptional mechanical stability and retain functionality under extreme deformation.
- These surfaces hold significant potential for applications requiring flexible, self-cleaning, and protective materials.
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