Hard Epoxy Coating with Lasting Low Ice Adhesion Strength

A high-hardness ( H ) coating typically has an elevated ice adhesion strength (τ), while a soft coating tends to shed ice easily. We recently reported a one-step process for a bilayer polyurethane coating that achieved both high H and low τ, effectively decoupling H from τ. However, these low τ values remained stable only through 12 icing/deicing cycles, beyond which τ rapidly increased. To maintain consistently low τ, another bilayer coating is prepared using a diamine, an epoxy compound, and poly(glycidyl methacrylate) with poly(dimethylsiloxane) (PDMS) side chains. This coating features a bulk hardness of 0.31 ± 0.03 GPa, PDMS nanopools in the matrix, and a liquid-like PDMS brush layer on the surface. A silicone oil mixture (SO m ) can be added to the formulation before coating formation. Increasing the SO m content enlarges PDMS/SO m nanopools and surface roughness. Lubricated coatings are produced by applying SO m or individual silicone oils (SOs) of varying viscosities to preformed nonporous and microporous coatings. This study compares ice-shedding properties of these coatings over 30 icing/deicing cycles. Results show that the smooth bilayer epoxy coating, lubricated with 1.55 g/m 2 SO m, maintains τ values <5 kPa, 100 times lower than glass, after 30 icing/deicing cycles. This marks the first polymer coating to simultaneously exhibit high H alongside such consistently low τ values over numerous icing/deicing cycles.