Multifunctional polyurethane-based coating with corrosion resistance and anti-icing performance for AA2024-T3 alloy protection

In this study, we present the development of advanced anticorrosive icephobic coatings tailored for AA2024-T3 surfaces. These coatings were engineered using polyurethane, incorporating fluoropolyol and isocyanate modified with hydroxyl-terminated silicone oil and fluoroalkyl polyhedral oligomeric silsesquioxane (F-POSS) particles. Surface characterization involved contact angle and sliding angle measurements, as well as atomic force microscopy. The icephobic efficacy was evaluated through a battery of tests including differential scanning calorimetry, delay of freezing time measurement, impact and non-impact ice adhesion measurement (push-off and centrifuge), and the ice accretion method. Electrochemical impedance spectroscopy served to evaluate the anticorrosion performance of the coatings. The integration of silicone oil and F-POSS led to notable improvements in contact angles, increasing from 92° to 127°. The lowest sliding angle (6°) was obtained for the coating containing both silicone oil and F-POSS. Topographical images showed the essential role of F-POSS in providing a rough surface structure. The optimal coating formulation consisted of 10 wt.% F-POSS particles and 5 wt.% silicone oil, resulting in a water contact angle of 127°, a sliding angle of 9°, approximately 42 days of surface protection, and an impedance value of 4.8 × 108 Ω·cm2. Remarkably, this coating demonstrated exceptional durability in terms of icephobic properties, maintaining a push-off ice adhesion strength of 9.3 kPa even after 15 icing/de-icing cycles, confirming its desirable icephobic performance.