Salt-impregnated asphalt could keep roads ice-free, without the need for the spreading of salt. Researchers report in a paper, “Gelation-Stabilized Functional Composite-Modified Bitumen for Anti-icing Purposes”Industrial & Engineering Chemistry Research, in ACS’ journal Industrial & Engineering Chemistry Research a new road material that could de-ice itself.
A team of scientists Led by Dr Seda Kizilel at Turkey’s Koc University mixed the salt potassium formate with a hydrophobic (water-repelling) polymer known as styrene-butadiene-styrene.
That mixture was in turn added to bitumen, which is the main binding ingredient in asphalt. The resulting composite material was found to be just as tough as regular bitumen, yet its salt content “significantly delayed” the formation of ice on its surface.
In lab tests, it continued to release salt for a period of two months, still melting ice as it did so. The effect could reportedly last for much longer on an actual road, however. This would be because as the top layer of salt-depleted asphalt was worn away by traffic, fresh “salty” asphalt would be exposed from beneath.
With this in mind, the researchers believe that the salt-polymer composite asphalt could remain active for years. A paper on their research was recently published in the journal Industrial & Engineering Chemistry Research.