Michigan State University (MSU) researchers have developed a pathbreaking liquid nanofoam liner for football helmets.
According to assistant professor Weiyi Lu and his team, the novel liquid nanofoam material could make on-field concussions a thing of the past.
The material is itself full of tiny nanopores. Each of these pores possess a diameter between two and 200 nanometers and that creates a large amount of surface area.
Infact, the whole area of MSU’s Spartan Stadium could be folded up into one gram of nanofoam, opines Lu.
Ordinarily, the material is rigid and adding liquid would fill the holes.
To fix this, Lu and his team coated the nanopores with a hydrophobic or water repellant silicone layer made from an organic silyl chain that prevents liquid from being absorbed by the material.
As a result, the saltwater liquid inside the nanofoam material becomes pressurized during an impact.
“When the pressure reaches the safety threshold, ions and water are forced into the nanopores making the material deformable for effective protection,” notes Lu.
“In addition, the liquid-like material is pliable enough to form into any shape: Helmets are pretty much one shape but the liquid nanofoam material can be made to fit a person’s specific head shape or profile.”
In early laboratory tests, Lu and his team showed that the three-quarter-inch piece of solid foam traditionally used in helmets fared miserably when compared to their eighth-inch liquid nanofoam liner.
According to Lu, the nanofoam was also able to sustain continuous multiple impacts without damage. Moreover, the results were identical from test one through test 10.
Beyond football and military helmets, the nanofoam material could be used in passive safety devices such as automobile air bags and bumpers.
It could also be used to protect people and buildings from earthquake vibrations – and mitigate intensive impacts like those caused by a bomb blast.
Image and content: MSU/Emilie Lorditch