The result is a LFT rim-stiffened helmet liner that reduces the crush deflection by 66 percent with an added weight penalty of only 19 percent to the outer shell of a helmet. However, Vaidya wants to make the weight even lower. He’s currently in discussions with helmet manufacturers to integrate the concept into their designs. He says this innovative way of demonstrating this approach could fit well with similar needs in personal protection and systems. In other words, there are a lot of avenues in the defense market to pursue, he says.
A GREEN VISION
Project: Natural Fiber Pultrusion
School: University of Mississippi
Location: University, Mississippi
Director: Ellen Lackey
These days, environmentally-friendly composites are permeating the marketplace and the technology is seen as a viable alternative. But, these solutions weren’t always smiled upon. Just ask University of Mississippi Professor Ellen Lackey, who began working on natural fiber composites at the turn of the century. “We faced skepticism from the composites community because people hadn’t adopted the idea of green composites yet and we had to convince people it was viable,” she says.
Lackey’s vision was to use natural fibers (specifically, industrial hemp) in pultruded composites with polyester resins and bio-based polyurethane resins. “The natural fibers had been used in some of the thermoplastic applications, but very few people had looked at thermosets with natural fibers,” says Lackey.
The school used the hemp as a hybrid reinforcement along with e-glass. “We thought that despite a slightly lower strength, the hybrid could still be a useful material and allow us to utilize the natural fiber. We also looked at surface modifications because one of the issues with natural fiber resin adhesion and resin/fiber compatibility.”