Anti-icing performance of superhydrophobic coating prepared by modified fluorinated silicone

Abstract

This paper investigates the anti-icing effect of hydrophobic coating, which has similar characteristics with a superhydrophobic surface. First, the factors affecting the wettability of water droplets on a solid surface were theoretically analyzed. Using hydrolytic condensation reaction, low-surface-energy materials were prepared based on a modified vulcanized silicone resin. Different sizes of silica particles were added in a fluorinated silicone resin to prepare the superhydrophobic coatings, considering the fractal theory. In the coating test characterization phase, the microstructure of the particles-doped coating surface and the contact angle of water droplets on different coating surfaces were investigated and analyzed. To visually analyze the effect of coating anti-icing property, icing tests were carried out in an icing wind tunnel after coating the test pieces by different coatings. The results show that the surface of the hydrophobic coating mixed with particles of different sizes forms a composite microstructure, which has a better roughness. The contact angle test result shows that the contact angle of water droplets on the fluorinated silicone resin-coated surface is 10° higher than that on the ordinary silicone resin-coated surface, and increases by nearly 20° in the coating with different particle sizes compared with the uniformly sized particles coating, thus achieving a superhydrophobic surface effect. The different coated test pieces were set in an icing wind tunnel to test their anti-icing abilities, and the results indicate that the superhydrophobic coating with a fractal structure after being cured does not only have a lower icing weight, which is reduced by 35.6% and 25.9% at the wind speed of 5 m·s-1 and 15 m·s-1, respectively, compared with the uncoated surface, but also has longer anti-icing effect than the uniformly rough surface. Therefore, the designed superhydrophobic coating has an outstanding anti-icing ability. In conclusion, the designed superhydrophobic coating achieves a superhydrophobic surface and has a better anti-icing performance, as confirmed through a series of performance tests.

Keywords

• silicone
• fluorination
• superhydrophobicity
• fractal
• contact angle
• anti-icing