Dual Component Passive Icephobic Coatings with Micron-Scale Phase-Separated 3D Structures.

Area of Science:

• Materials Science
• Surface Chemistry
• Tribology

Background:

• Passive icephobic coatings are crucial for industries such as aerospace and energy.
• Achieving low ice adhesion thresholds (< 20 kPa) requires advanced material strategies.
• Existing solutions often involve fluids or sacrificial elements, limiting their durability.

Purpose of the Study:

• To develop a durable, passive icephobic coating with significantly reduced ice adhesion.
• To investigate the self-segregating microstructure of the coating and its effect on performance.
• To explore the modularity of the coating system by substituting components.

Main Methods:

• Combining perfluoropolyether (PFPE) and poly(ethylene glycol) (PEG) in a segmented polyurethane thermoplastic elastomer.
• Utilizing spray application to create a mechanically tough film.
• Characterizing the coating's micron-scale segregated 3D morphology with discrete PFPE and continuous PEG phases.
• Measuring ice adhesion strength (τ_ice) under realistic accretion and centrifugal shedding conditions.

Main Results:

• The coating exhibited exceptional ice adhesion reduction, up to 1000× lower than aluminum (τ_ice < 1 kPa).
• A unique segregated 3D microstructure with distinct PFPE and PEG phases was observed.
• The spray-applied film was solid, mechanically tough, and free of sacrificial elements.
• The system demonstrated modularity, allowing for component substitution (e.g., PEG/PFPE with poly(tetramethylene oxide)) to study performance drivers.

Conclusions:

• The developed PFPE-PEG polyurethane coating offers a highly effective passive icephobic solution.
• The self-segregating microstructure is key to achieving ultra-low ice adhesion.
• The coating's mechanical robustness and modular design present significant advantages for industrial applications.