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

A passive icephobic coating (τice < 20 kPa) is an enabling technology to many industries, including aerospace and energy and power generation, with recent efforts in materials research identifying strategies to achieve this low adhesion threshold. To better meet this need, we have combined low surface energy perfluoropolyether (PFPE) and hydrophilic poly­(ethylene glycol) (PEG) species in a segmented polyurethane thermoplastic elastomer. Coating microstructure presents a segregated 3D morphology at the micron-scale (1–100 μm) with discrete PFPE and continuous PEG phases self-similar through the thickness. Spray application produces a solid, mechanically tough film free of additive fluids or sacrificial elements, demonstrating exceptional ice adhesion reduction up to 1000× lower versus aluminum (τice < 1 kPa), as measured under environmentally realistic accretion and centrifugal test shedding conditions. Finally, the modular nature of the synthetic system allows PEG and PFPE to be exchanged for poly­(tetramethylene oxide) to investigate performance drivers.