Biomimetic fluorinated polysiloxane/polyurea-silica coating with rapid self-healing and anti-icing performances
Jie Liu, Xiaojun Wang, Nan Zheng, Yao Pan, Yayu Zhang, Fu Xia, Haohan Zhang, Peng Wang, Changming Zhang, Xin Min, Wenge Li
Abstract
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-SiO<sub>2</sub> 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 remained 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.