Icing impairs operation of helicopters, aircraft, antennae, wind turbine, power and communication lines, ships, superstructures, canal locks, etc. Prevention or easier removal of icing requires reduction of its adhesion strength.

Low ice adhesion coating has been the worldwide interest of research fields. NASA Lewis has performed icing research for over 6o years, operating the world's largest refrigerated icing tunnel, the Icing Research Tunnel (IRT). The airspeeds up to 160m/s (350 mph), low temperature to -30° C (-20° F), water spray droplets 15-40 micron with content of 0.2-3.4 g/m3 are for ice impact ice tests. During 60 years period numerous requests have been received from organizations ranging from in size from individual inventors to large corporations to test "ice-phobic" coatings for prevent ice from adhering to aircraft surfaces. Many large corporations, such as DuPont, PPG, Dow Chemicals, and BFGoodrich Aerospace maintain the interest in the development of low ice-adhesion coatings. NASA witnessed that the best low ice adhesion samples tested in IRT with a record of about 50% of uncoated forces.  

Fluonova, Inc. (previous Elastic Ceramic Coatings, ECC) have involved in low-ice-adhesion coatings and had provided 12 different material samples tested in IRT and had 2 types with lowest record of about 30-50% of uncoated forces.** By understanding the material structure-ice adhesion relation. Fluonova has improved its technique on low ice-adhesion coatings. Now it provides FC-Al FC-E series of low ice-adhesion coatings. FC-AL series is for aluminum and light alloys. It is a perfluoro functional polymer that requires heating (120-150° C) treatment to form a transparent permanent thing coating with low ice-adhesion, corrosion resistant, low dielectric properties. FC-E series form low ice adhesion coating under ambient temperature.

FC-Al series can be used to reduce ice adhesion on aluminum and other light alloys for prevent surface ice acumination. The power line and wind turbine surfaces are benefited not only with low ice-adhesion but also corrosion resistance. FC-E series is elastomeric for low ice adhesion coatings.

FC-E series can be used to reduce ice adhesion on glass windows, cables, and electric wires. 

Ice adhesion is results from surface hydrogen bonds with water, and Van der Waals forces is a secondary force. Low water-solid contact area, high water-air contact area, low surface wetting combine to reduces ice-adhesion. The material submicron-nanometer structures on low energy surfaces are very important. In the nature, lotus plants and feathers of some birds shown us how the simple wax and the superstructures of surfaces provided super hydrophobic clue. Super hydrophobic surfaces shown low-icing adhesion for low speed wind such as under 50 m/hr speed. However, low adhesion for impact ice is much more difficult to solve. High speed wind creates high impact on surfaces. The occluded air pocket under such water interface is under pressure. In such case, water penetrates into void. When water freezes into ice, the volume expands. If submicron-nanometer structures are rigid, repeated water-ice cycles or water-icing-ice remove cycles would remove such rigid structure. The efficacy of low icing adhesion of man made rigid super hydrophobic surfaces drops with each water-icing cycles during impact icing conditions. Second challenge is: the low ice adhesion coating should resist environmental contamination. Super hydrophobic surfaces, nature or man made, both loss efficiency under contamination. For example, surfactant solution permanently destroy super hydrophobic of Lotus leave, feathers and many man made samples. Only fluorinated polymer surfaces are recoverable by water wash. However, there are a big gap to reach the feathers of birds which have delicate surface structures with super strong mechanical strength and elasticity. We tested our super hydrophobic surfaces, for example, porous surface with air occlusion, etched surface with viscous silicone supplying structure, semi-liquid structure, needle forest structures are all failure with high speed impact icing.  We are still working on fluoropolymers with special submicro-nanometer structures with elastomeric properties required to reduce impact ice adhesion.

Fluonova Inc provides LuxeColor® FSI series for glass window application, such as the glass windows for automobile, boat, and aircraft. The application is easy: 1). Clean the glass and pay attention to remove any residue of surfactants completely; 2). Wipe FSI coating saturated paper on the glass and polish with a small size paper to have a clear view, and 3). Waiting for 4 hours.   

** AIAA-97-0303: Tests of the Performance of Coatings for Low Ice Adhesion, D. N. Anderson, NASA Lewis Research Center, Cleveland, OH and A.D. Reich, BFGoodrich R&D Center, Brecksville, OH