(unkowgayle / Pixabay)

Forget research into artificial intelligence applications nobody asked for. A team of scientists from the University of Illinois Chicago is tackling an issue every Midwesterner can get behind: Is there a way to make ice less “sticky”?

Imagine walking out to your car on a wintry Chicago morning and instead of spending 15 bitterly cold minutes chipping ice off your windshield, the ice slides off with ease. Or maybe it never attached to the windshield in the first place.

This is the future Sushant Anand, associate professor of mechanical and industrial engineering at UIC, is working toward.  

Ice is a fascinating material, he said, one that’s absolutely essential to life on Earth — from reflecting the lion’s share of solar radiation to insulating lakes and ponds during the winter — but it’s also a pain in the neck (and other body parts) for pedestrians and motorists, and can be catastrophic when it forms on airplanes. 

The question for Anand is how to take advantage of the good while overcoming the bad.

For a substance that’s literally just frozen water, ice isn’t particularly well understood. So Anand, along with colleagues at UIC and Argonne National Laboratory, set out to explore what makes ice tick. Specifically, how does ice stick to surfaces?

The UIC team is hardly the first group of researchers to investigate the stickiness of ice — how well or stubbornly it adheres to a surface — but they came at the problem from a new angle.

“(Researchers) typically take pure water and make it stick,” said Anand. “But in real life, water is not pure.”

In real life, water picks up impurities either from the atmosphere or collects them when it hits buildings, streets or other structures. So the UIC team studied the behavior of ice formed from water containing varying concentrations of three different categories of impurities — salts, alcohol and soap (or salts, solvents and surfactants).

The results, recently published in the journal Material Horizons, showed that the impurities play a significant role in stickiness. In general, the more impurities, the less sticky the ice.

Why?

The researchers found that ice expels contaminants that drain along channels and ice-grain boundaries toward the ice base, where it forms a liquid layer that gives ice extra slipperiness. (In this context “extra slipperiness” means “less sticky” or less adherent.)

But there were some exceptions, Anand noted.

Impurities combined with really cold temperatures causes ice to stick with even greater intensity, and the rate at which ice forms also affects its stickiness. If it freezes slowly, researchers discovered, the ice itself will purge all impurities and become stickier. How that happens could have implications for desalination methods, Anand said.

As is often the case with scientific experiments, for every question answered, two more are raised. 

The UIC team will take what it learned about the role of impurities in ice formation and conduct further research into ice repellent coatings, which ultimately could lead to safer roads and fewer people injuring themselves in falls on the ice.

“The research we do should benefit society,” Anand said.

So don’t throw away your ice scraper yet, but its days may be numbered.

Contact Patty Wetli: @pattywetli | (773) 509-5623 |  [email protected]