UNH researchers discover way to create new smart material

For possible use in enhanced protection applications, building facades

For the first time, researchers at the University of New Hampshire have shown that rotating cells in chiral cellular solids, a foam-like substance, could lead to the creation of a new smart material.

Since the chiral auxetic cellular solids are a foam, they are very flexible in volume change and are a good candidate for energy absorption and enhanced protection applications, such as cushioning for helmets, packing materials and sports or military protective armor, the researchers say. They can also be used as a smart facade in buildings, where each cell can open or close automatically when the light intensity or temperature changes during the day to help save energy.

“Changing the geometry of the chiral auxetic cellular solids can allow the material to respond differently to certain things like temperature, humidity, light, or impact,” said Yaning Li, assistant professor of mechanical engineering. “For instance, foam in a helmet made of this material could become denser on impact and offer more protection, or a smart medical bandage could be triggered to release medicine based on different levels of swelling.”

In the study, recently published online in Advanced Engineering Materials, the researchers outline their approach to alter the behavior of the foam material by changing it on a cellular level.

After increasing the rotation of the cells, the researchers used a 3D printer to create a new model that showed an elevated internal efficiency, which allowed it to absorb more energy.