Designing soft materials with interfacial instabilities in liquid films.

Area of Science:

• Materials Science
• Fluid Dynamics
• Soft Matter Physics

Background:

• Natural soft materials utilize hierarchical structures for functionality.
• Technological applications require scalable, flexible, and robust fabrication methods for structured materials like metamaterials and functional surfaces.

Purpose of the Study:

• To develop a novel fabrication pathway for structured materials by harnessing fluidic instabilities.
• To demonstrate the ability to tailor the size and structure of fabricated materials.

Main Methods:

• Utilizing the inherent periodicity of the Rayleigh-Taylor instability in thin polymeric liquid films.
• Solving the inverse design problem to control the instability and resulting structures.
• Curing the polymer to solidify the pendant drop lattices and permanently sculpt the material interface.

Main Results:

• Spontaneous fabrication of structured materials with pendant drop lattices.
• Tailoring of structure sizes over a range of two decades by controlling the fluidic instability.
• Achieving a scalable, all-in-one fabrication methodology.

Conclusions:

• The Rayleigh-Taylor instability offers a promising route for the scalable fabrication of functional structured materials.
• This method provides design flexibility and robustness, applicable to metamaterials and functional surfaces.
• The technique shows potential for extension to smaller scales, even below continuum mechanics limits.