Researchers at MIT have developed a new process to make nanowire-based fabrics that are stronger than Kevlar.
In the past few years, micro and nanodevices such as MEMS and NEMS have become a rapidly developing field of research.
As machines and robots become smaller and lighter, there is a larger need for new materials and production processes to make tiny components, circuits, and devices to meet these ever-increasing demands.
Now, MIT engineers have potentially solved many of these issues by developing a completely new process to craft new low-cost nanofibers.New #MIT #nanofibers are stronger, tougher, and cheaper than Kevlar.Click To Tweet
Next-Gen Alternatives to Kevlar
After the Second World War, research to develop new lightweight textile fibers that could replace steel intensified rapidly.
Poly-para-phenylene terephthalamide, better known under its brand name Kevlar, is a synthetic fiber (a polymer) of the aramid family which gradually became the solution to this issue.
Developed in the 1960s by Du Pont de Nemours, the same company which developed nylon (patented in 1935), Kevlar has been on the market since 1972 and has become an integral material in many different industries.
Lightweight, incombustible and stronger than steel, Kevlar naturally became widely used by the military before being introduced into the aerospace and aeronautics industries.
Kevlar is used in the fabrication of many other products that need to be strong and lightweight such as safety equipment, professional clothing, and sports equipment.
In short, Kevlar has become an integral fabric in a number of industries and will remain in use for the foreseeable future. However, Kevlar is created with the use of woven fibers that are very complex and expensive to make.
As strong, light and malleable as it is, Kevlar is slowly being overtaken by emerging technologies such as nanodevices and material scientists are gradually looking elsewhere for stronger and less expensive alternatives.
MIT’s Nanofibers: Stronger, Tougher, and Cheaper Than Kevlar
In this search for a cheaper and stronger fiber, researchers at MIT have been working for years on ways to make certain materials fulfill their promising engineering prospects. In this vein, researchers experimented with the geometry of 2D graphene to make 3D forms, which has been relatively successful.
Now, these researchers are back with a whole new process to produce nanowires with exceptional properties.
Developed by a team led by Gregory Rutledge, professor of chemical engineering at MIT, the group used a process called gel electrospinning to produce fibers that are ultrafine yet stronger and tougher than Kevlar while also being cheap and easy to make.
The main challenge for the research team was eliminating the tradeoffs between strength and toughness that material scientists usually have to make.
“It’s a big deal when you get a material that has very high strength and high toughness,” said Rutledge. “That’s the case with this process, which uses a variation of a traditional method called gel spinning but adds electrical forces.”
According to Rutledge, there are several other high-performing materials (like Kevlar and Dyneema), and other forms of fibers (carbon and ceramic fibers), but, on a per-weight basis, their nanofibers outperforms all of these by a substantial margin.
At less than 1 micron (billionths of a meter) in width, these gel-electrospun nanowires can be woven to make cheap protective gear such as body armor and protective equipment that is as equally strong as existing products but far lighter. However, says Rutledge “they may have applications we haven’t thought about yet because we’ve just now learned that they have this level of toughness.”