Researchers Create Self-Cleaning Concrete That Repels Liquid
Forget power washers and new paint jobs, the buildings of the future may do all the work for you. That's if the building industry embraces new self-cleaning concrete a team of researchers just developed.
Researchers created a new type of concrete that is not only strong, heat-insulating and soundproof but is able to repel materials such as coffee or soda. Even better, it bounces dust particles off the wall along with the offending liquids. The researchers work was published in journal ACS Applied Materials & Interfaces.
Perfecting self-cleaning surfaces has long been a goal
Scientists have tried to create self-cleaning surfaces over the years, typically adding hydrophobic materials to the surfaces. But there are limitations. The chemicals tend to scratch and wear over time. Not to mention the chemicals weaken concrete which isn't ideal for building structures.
The researchers wanted to create an easy method to make concrete self-cleaning and achieved that by adding oil, an emulsifier and a hydrophobic silicone polymer called polydimethylsiloxane (PDMS). The materials were added to wet concrete. The oil, thanks to the emulsifier, formed droplets that contained the PDMS. The concrete was then dried and heated evaporating the oil and leaving behind PDM pores on the concrete. The resulting concrete was lightweight, mechanically strong and repelled dust and liquids.
A bevy of beverages tested
The researchers tested its abilities to repel all sorts of liquids including milk, beer, soy sauce, coffee and dyed and none left a stain. Even after exposing the concentrate to mechanical grinding, heat treatment and exposure to chemicals it remained "superhydrophobic."
The researchers led by Xin Xu got the idea for the self-cleaning concrete from nature. There are many examples of self-cleaning surfaces whether it leaves collecting raindrops during a spring rainstorm or droplets of water collecting on a geckos' feet.