Silicone based superhydrophobic coating efficient to reduce ice adhesion and accumulation on aluminum under offshore arctic conditions

A cost-effective superhydrophobic coating has been developed by chemical etching and spray coating of a commercially available co-polymeric silicone, composition of which was confirmed by Infrared. Morphological studies by scanning electron microscope show a micro-nano rough pattern that increased with the wt.% content of the sprayed silicone film after drying. At an optimum 5 wt.% of silicone, contact angle reached a maximum of 154 +/- 2 degrees for which value a roughness R-rms of 2.7 +/- 0.2 mu m was measured. This superhydrophobic coating gave interesting icephobic properties. Ice adhesion measured by centrifuge testing were up to 12 times lower, as compared to bare aluminum. In addition ice accumulation tests performed under two kinds of laboratories frozen sea spray, the first named white cap spray (WCS) and the second interaction spray (IS) show that the mass of ice over the best optimized superhydrophobic coating is reduced by 5% and 45%, respectively. Those reductions in ice adhesion and accumulation can be interpreted, according to Cassie-Baxter's model, by an air fraction of 85% entrapped at the superhydrophobic interface. This cost-effective superhydrophobic coating is looking promising for offshore applications under Arctic icing conditions, as it reduces ice adhesion and accumulation on metal structures.