Scientists at MIT have created what they call the most waterproof material ever, based on lessons from nature. The surface consists of tiny ridges on top of a silicon surface, which makes water droplets bounce off the material, keeping it dry.
The material is ‘super hydrophobic’, or extremely water-resistant. The inspiration for the material coating comes from such highly advanced, but very delicate, naturally evolved surfaces as leaves and wings. The patterns on the wings of certain butterflies and plant leaves ensure that the organism is kept water free.
Usually, hydrophobic materials work by making sure that only a tiny part of a water droplet touches the leaf or wing. This super hydrophobic material works using a different principle: reducing contact time. The ridges applied make the droplets shatter ‘axisymmetrically’ – into symmetric shapes but in different directions. Tests on common metals proved that the coating worked exceptionally well.
This development is particularly significant as it shows that the coating can be applied to tough materials, not just the relatively fragile textiles and polymers that are commonly used for such coatings.
It is also a 40% improvement on existing materials, according to the team at MIT that developed the super hydrophobic coating. In theory, the coating can be applied to ceramics, clothing and cars, so any number of applications are possible. It’s easy to imagine the use of the coating in fabrics, on roof tiles and on glazing.
Other possibilities are perhaps less obvious. Applying the coating to jet engines could reduce the risk of ice forming, meaning safer travel, and applying the coating to power lines means they shouldn’t freeze or corrode as quickly.
The scientists, led by Professor Kripa Varanasi, are now looking for the design community to step up with ideas for applications. He is looking to optimise the coating to improve the quality of the waterproofing even further.
Image credits: MIT