Friday, February 23, 2024

Researchers develop strongest and toughest glass inspired by seashells

Glasses have numerous applications because of their exceptional transparency and stiffness; however, poor fracture, impact resistance, and mechanical reliability limit the range of their applications.

Now, scientists from McGill University have developed stronger and tougher glass, inspired by the inner layer of mollusk shells, while retaining good transparency.

The inner iridescent layer of molluscan shells, known as nacre (mother-of-pearl), is one of nature’s outstanding examples of a durable brick and mortar structure. Made of stiff, inorganic aragonite platelets and soft, elastic biopolymers, the material combines toughness with a surprisingly high degree of strength and stops cracks from propagating.

Unbreakable glass comparison.
Unbreakable glass comparison. Credit: McGill University

For their new study, the researchers replicated the architecture of nacre with the layers of glass flakes and acrylic, yielding an exceptionally strong yet opaque material that can be produced easily and inexpensively. To make the composite optically transparent, they turn the refractive index of the acrylic so it seamlessly blends with the glass. This makes the material much stronger and tougher than regular glass but still transparent.

“Until now, there were trade-offs between high strength, toughness, and transparency. Our new material is not only three times stronger than the normal glass, but also more than five times more fracture-resistant,” says Allen Ehrlicher, an Associate Professor in the Department of Bioengineering at McGill University.

Researchers say the new material has the resiliency of plastic and could be used to make stronger displays for cell phones and other devices in the future, among other applications.

In future work, the team plans to improve it by incorporating smart technology allowing the glass to change its properties, such as color, mechanics, and conductivity.