Your tears inspire scientists to design new adaptive material

More than a few tears have been shed in the pursuit of scientific discovery, but this time it’s the tears that have inspired the discovery. A team of scientists at the Wyss Institute at Harvard University and Harvard’s School of Engineering and Applied Sciences (SEAS) have just announced in the journal Nature Materials they have created a new adaptive material with adjustable transparency and wettability.

The material is a new type of liquid-infused elastic porous surface — basically a liquid film coating and bound to a porous substrate. The elastic element is the key to making this substance work. When the substrate is stretched, twisted, or otherwise deformed, it causes the liquid surface to change its shape. This physical change in the surface can be used to dynamically control transparency and wettability (how well liquids move across the surface).

Scientist took inspiration from the way the eye coats itself with tears. A continuous trickle of tears from the tear ducts join up on the surface of the eye to protect it. This is similar to the way the liquid film coats the substrate.

In the video above you can actually see a liquid running across the surface of the new material. When the substrate is stretched, the film becomes more opaque and rough, causing the droplet to stop in its tracks. On the small scale, this might not seem like a huge accomplishment, but it could change the way water systems and industrial machinery are made.

Wettability control is just the beginning, though. Researchers believe the topographical changes triggered by manipulation of the substrate could be used to affect adhesion, among other properties. We could see ships with hulls that never need to be cleaned of barnacles, or medical equipment that doesn’t allow the growth of nasty biofilms. Elastic layers that respond to temperature, light, and other triggers could be used to make the process automatic.