Biomimetic fluorinated polysiloxane/polyurea-silica coating with rapid self-healing and anti-icing performances

By adjusting the fluorine content and the molar ratio of 4,4'-dicyclohexylmethane diisocyanate (HMDI) to isophthalaldehyde (IPAL), a novel fluorinated polysiloxane/polyurea (FPUI) with an optimized dual-healing network of hydrogen and imine bonds is synthesized. Using FPUI as a low-surface-energy matrix and incorporating nano-SiO₂ via spraying, a biomimetic fluorinated polysiloxane/polyurea-silica (FPUS) anti-icing coating is developed, achieving durable anti-icing and de-icing performance. FPUS demonstrates complete self-healing within 15 min at room temperature, with tensile strength, elongation at break, and shear strength of 1.43 MPa, 159.32%, and 1.14 MPa, respectively. Water droplets on FPUS-coated surfaces (glass, carbon steel, plastic, and rubber) exhibit significantly longer freezing times compared to uncoated substrates. For instance, on uncoated glass, water freezes in 27 s, whereas on FPUS-coated glass, freezing is delayed to 619 s. Additionally, ice adhesion strength on uncoated glass is 364.16 kPa but was drastically reduced to 23.25 kPa on FPUS-coated glass. Even after 10 freeze-thaw cycles, the adhesion strength remains stable, increasing only slightly to 26.65 kPa. Beyond its anti-icing capabilities, FPUS also exhibited self-cleaning, antibacterial, and anti-corrosion properties. These features make it a promising candidate for protecting outdoor infrastructure and engineering equipment, such as wind turbine blades, photovoltaic panels, power transmission lines, aircraft, and offshore oil platforms.