Ice build-up tends to be a big problem in large structures such as buildings, airplanes, and ships. Researchers have now developed a spray-on coating that causes ice to fall away, even with just a slight breeze.
Snow and ice accumulation can cause roofs to collapse, while build-up on windows and walls may cause water damage. Such an accumulation of ice on large surfaces is not just problematic but also rather hazardous, especially in structures such as the wing of an airplane or on the side of tall buildings.
Previous ice-repellent coatings do repel ice, but the problem is that they do not repel ice in large surfaces as effectively as they do on smaller surfaces. Unfortunately, it is those structures with larger surfaces that need to repel ice the most.
Ice-Proofing Spray-On Coat
Evidently, previous researches focused primarily on lowering the adhesion strength of ice on a surface, meaning that they focused on the force required to separate the ice from the surface. However, this meant that as the surfaces got larger, the force required to tear the ice from the surface would also need to be stronger. So eventually, the sprays became ineffective once the surface was too large.
Now, researchers from the University of Michigan have developed an ice-proofing spray that can repel ice even on large surfaces. In fact, it is so effective that the ice would fall away from the structure even just from a light breeze or from its own weight.
In developing the new ice-proofing spray, researchers focused on low interfacial toughness (LIT). So instead of focusing on breaking the ice’s adhesion strength, in that the ice sheet had to break free as a whole, the focus was on encouraging cracks to form between the surface and the ice. Once cracks begin to form, it can quickly spread throughout the sheet and eventually lead the entire sheet to fall away no matter how large it is.
The team tested the coat on several surfaces, and each time the ice fell away immediately. On the control surfaces, one of which was not sprayed with any coat and another was sprayed with an earlier spray, the ice stuck fast.
Now, the team is working on improving the durability of their spray.
The study is published in Science.