How to design an invincible armor for your favorite superhero, so that it is light for fast movements, but strong enough to protect him from enemies?
It is from this rather nerdy question that a group of materials scientists from the Universities of Connecticut and Columbia worked to create a strong, low-density material by combining two unlikely elements: glass and DNA.
According to the researchers, assisted by the Brookhaven National Lab, the material they developed is the strongest known so far.
How is such a material made?
So how do you combine strength and lightness? The researchers built one DNA skeleton, which they then coated with the glass, a material that is only apparently fragile. One cubic centimeter of perfect glass can in fact withstand 10 tons of pressure, an amount three times higher than that which tragically caused the Titan submarine to implode.
It is far from simple to produce a large sheet of glass without defects, but it is possible to create small and perfect pieces, as long as you limit yourself to thicknesses of less than micrometer (one millionth of a meter). And this is where it comes into play glass density, decidedly more contained than that of ceramics and metals, which favors the creation of resistant and light materials.
The frame of the material was therefore composed of pieces of DNA, with specific lengths and chemical characteristics, which self-assembled, composing a skeleton of filaments. The latter were covered with a very thin layer of glass, leaving much of the volume of the material empty. This expedient allowed us to obtain a strong, yet lightweight nanolattice with four times the strength and five times the density of steel.
Potential applications
Thanks to this research, important engineering opportunities can now be opened up. The ability to create strong and lightweight nanomaterials, with a 3D structure designed using DNA, will allow us to overcome the limits of traditional metallurgical techniques and improve the properties of materials used to make medical devices, armor, airplanes and cars. Nanogratings, to cite just one example, will be the main supporters of the lightness of vehicles: one of the fundamental characteristics for extending the autonomy of electric vehicles.
Sources: today.uconn.edu
