UNL Engineers Develop New Strong, Yet Tough Nanofibers
An engineering team at the University of Nebraska-Lincoln have just developed a new nanofiber that is simultaneously tough and strong. Strength determines how well a material can carry a load, while toughness determines how much energy is required to break said material. Before, it was believed that you would have to sacrifice one attribute for the other, but the UNL team were able to prove that theory wrong. They discovered that by making nanofiber more thinner than it was ever done before, they could give the material not just more strength, but toughness as well.
The team is comprised of Yuris Dzenis, the team's leader as well as a McBroom Professor of Mechanical and Materials Sciences at UNL, and his engineering colleagues Dimitry Papkov, Yan Zou, Mohammad Nahid Andalib, Alexander Goponenko, and Stephen Z.D. Cheng. The National Science Foundation, the Air Force Office of Scientific Research, and the U.S Army Research Office Multidisciplinary University Research Intiative all provided the funding for the group's research.
The UNL team developed the thin, polyacrilonitrile nanofiber using a technique known as electrospinning, where they applied high voltage to the synthetic polymer related to acrylic until a small jet of liquid ejected. This resulted in "a continuous length of nanofiber". The team stated that while the strength of the nanofiber came from its thinness, its toughness resulted from the "nanofibers' low crystallinity".
Dzenis says that this new nanofiber could be used to transform anything made of composite materials. He stated that body armor, airplanes, bridges, bicycles and more could benefit from this new material. He used body armor as an example, and pointed out that in order for body armor to stop a bullet, it needs material that can absorb the bullet's energy, which these nanofibers are capable of doing. He says,
"If structural materials were tougher, one could make products more lightweight and still be very safe."
[via University of Nebraska-Lincoln]