Byung H. Kim, a professor of mechanical and industrial engineering at the University of Massachusetts Amherst, is using a three-year, $272,719 grant from the National Science Foundation to develop a manufacturing process that imprints nano- and micro-scale features into a roll of continuously extruded material. Kim received the grant along with his research partner Donggang Yao, a professor at Georgia Tech and former UMass Amherst graduate student whom Kim supervised for master’s and doctoral degrees.
The process uses a roll-to-roll system similar to what other scientists use to create nano-scale coatings on material. But by using a heating system, the base material itself is textured and is a single layer thick, Kim says. The base material is extruded the same way many plastics are created and then imprinted with a pattern in a continuous sheet that is collected on a roll, Kim says.
“We use heat to mold the material, kind of like a waffle iron,” Kim says.
One of the benefits of this process is that there are many materials that can serve as the base and the textured patterns can be refined down to nano-scale tolerances. It also doesn’t require curing and is more efficient than other processes, Kim says.
Practical applications of this process include making textured materials that reduce drag on ships or aircraft, according to Kim. Further, wire grid polarizers can be produced to make the LCD panel on cell phones more efficient by recycling the light thereby making the batteries last twice as long. The nano-textured plastic sheet can show a desirable color pattern without any colorant such as dye. Vibrant color pattern with just texture can be used in anti-counterfeit durable plastic bills. Also, extremely sensitive sensors can be made with the periodic nano-scale textured sheet extruded, Kim says.
The grant supports fundamental research into continuous imprinting of nano-scale features on a wide variety of thermoplastic polymers that have differing physical and chemical properties and can be used for applications in energy, health care, biomedical devices, and in the automotive and telecommunications industries.
The research also holds promise for transferring this technology for industrial scale application in the near future, Kim says.