Nanofoams could create better body armor

U.S. researchers say new nanofoam materials could be used in body armor to prevent traumatic brain injury and blast-related lung injuries in soldiers.

Such materials could also protect buildings from impacts and blasts, they said.

"We are developing nanofoams that help disperse the force of an impact over a wider area," Yu Qiao, a professor of structural engineering at the University of California, San Diego, said. "They will appear to be less rigid but will actually be more resistant than ordinary foams."

The nanofoams are made up of a honeycomb structure and are very light, because the open pores of the honeycomb make up anywhere from 50 to 80 percent of the structure, the researchers said.

Researchers create the nanofoams by blending two materials together at the molecular level, then use acid etching or combustion to remove one of the two materials, creating nano-scale empty channels in the process, a university release reported Tuesday.

Samples with pore sizes around tens of nanometers perform best, they said, absorbing energy from an impact or blast over a wider area, making the material more resistant to such events.

By contrast, ordinary foams absorb energy in one localized area, leading to quick failure, a problem known as "damage localization."

"People have been looking at preventing damage from impacts for more than a hundred years," Qiao said. "I hope this concept can provide a new solution."