Smart blending technique could change way plastics made

A new “smart blending” process developed by Clemson University researchers could change the way plastics are made and improve their performance. Early results published in August’s Polymer Engineering and Science have already drawn interest from European and United States plastics manufacturers.

Dave Zumbrunnen, who heads the Clemson research team, said smart blending could bring plastics production into the 21st century. “Most people would be surprised to learn that many plastics are not optimized for their intended use due to limitations of existing manufacturing equipment,” he said. With a smart-blending machine, however, engineers can optimize the material for maximum effectiveness with only a few strokes on a computer keyboard.

Many plastics are mixtures of two or more plastics and additives. Smart blending arranges these plastics into functional internal shapes as small as 1/10,0000th the diameter of a hair.

That’s important because it’s those small-scale structures that determine the attributes, or properties, of the plastic or composite. The end result? Plastics that are tougher, electrically conductive, porous – whatever is needed for the particular end-product, but without expensive trial and error.

“Smart blending technology offers unprecedented control of internal structure development, said Zumbrunnen. He developed the process along with faculty and student researchers from Clemson’s Center for Advanced Engineering Fibers and Films.

Immediate applications could include improved food packaging films, personal hygiene products, light-interactive plastics and toughened plastics for automotive uses.

Smart blending could also be used to produce patterns for countertops and even better tasting breakfast cereals.

The Dow Chemical Co. is funding a smart blending study through the fibers and films center. “We are looking forward to the results and the further development of this technology,” said Craig Dryzga, senior R&D leader in Dow’s Fabricated Products Department. Dow is headquartered in Midland, Mich.

Zumbrunnen’s research sponsors include industry representatives such as Dow, as well as the National Science Foundation, Defense Advanced Research Projects Agency and the National Textile Center.

Equipment manufacturers are interested in commercializing the technology. Zumbrunnen predicted that the first wave of smart-blended plastics could be on the market within a few years.

Zumbrunnen’s research is based on the work of Hassan Aref, who developed what’s known as the theory of chaotic advection. In a seminal 1980s paper, Aref showed that particles in a fluid can move chaotically in response to simple agitations. The chaotic motions cause fluidic regions to become stretched and folded, forming the layers on which Zumbrunnen has based his work.

Aref, now dean of Virginia Tech’s College of Engineering, has called Zumbrunnen’s work “attractive and ingenious.”

Zumbrunnen’s work is a pivotal research initiative in Clemson’s fibers and films center. The National Science Foundation established the center as one of the nation’s elite Engineering Research Centers in 1998. It’s the only national Engineering Research Center to target fiber and film research.

“This technique could change the way we produce all polymer products – fibers, films and even injection-molded products,” said the center’s director Dan Edie.

Zumbrunnen, a recipient of the Presidential Faculty Fellow Award from The White House and a recent participant in the National Academy of Engineering’s prestigious Frontiers of Engineering symposium, is Clemson’s Warren H. Owen-Duke Energy Professor of Mechanical Engineering.