Researchers from the University of Houston have reported a new theory in physics called stress localization, which they used to create a durable silicone polymer coating capable of repelling ice from any surface. Image: University of Houston.Icy weather is blamed for multibillion dollar losses every year in the US, caused by delays to air travel and damage to infrastructure and power generation and transmission facilities. But finding effective, durable and environmentally stable de-icing materials has been stymied by the stubborn tenacity with which ice adheres to the materials on which it forms.
Now, researchers from the University of Houston (UH) have reported a new theory in physics called stress localization, which they used to tune and predict the properties of new materials. Based on those predictions, the researchers were able to create a durable silicone polymer coating capable of repelling ice from any surface. They describe the coating in a paper in Materials Horizons.
"We have developed a new physical concept and the corresponding ice-phobic material that shows extremely low ice adhesion while having long-term mechanical, chemical and environmental durability," they wrote in the paper.
Hadi Ghasemi, assistant professor of mechanical engineering at UH and corresponding author for the paper, said the findings suggest a way to take trial-and-error out of the search for new materials, in keeping with the movement of materials science towards a physics-driven approach.
"You put in the properties you want, and the principle will tell you what material you need to synthesize," he said, noting that the concept can also be used to predict materials with superb antibacterial or other desirable properties.
Ghasemi previously reported developing several new ice-phobic materials, but he said those, like other existing materials, haven't been able to completely overcome the problem of ice adhering to the surface, along with issues of mechanical and environmental durability. The new understanding of stress localization allows the new material to avoid that.
The new material utilizes elastic energy localization where ice meets the material, triggering cracks at the interface that cause the ice to slough off. Ghasemi said that minimal force is required to cause the cracks: the flow of air over the surface of an airplane can act as a trigger, for example.
The material, which is applied as a spray, can be used on any surface, and Ghasemi said testing showed it is not only mechanically durable and unaffected by ultraviolet rays – important for aircraft that face constant sun exposure – but also does not change the aircraft's aerodynamic performance. Testing indicates it will last for more than 10 years, with no need to reapply, he added.
This story is adapted from material from the University of Houston, with editorial changes made by Materials Today. The views expressed in this article do not necessarily represent those of Elsevier. Link to original source.