Plastic With Changeable Conductivity

Dr. Yueh-Lin (Lynn) Loo at The University of Texas at Austin, an assistant professor of chemical engineering, studies the plastic called polyaniline because it could serve as flexible, inexpensive wiring in future products such as foldable electronic displays and medical sensors.

By combining polyaniline with a chemical that gives it conductivity, Loo discovered she could increase the plastic’s conductivity one- to six-fold based on the version of the chemical added. Chemically altered polyaniline has several advantages over the more commonly used metals, like gold and copper, in devices other than computers. For example, Loo’s previous research has demonstrated that “doped” polyaniline can be manufactured in solution at room temperatures and without vacuum chambers. Producing metal-based wires requires special manufacturing conditions in addition to the high cost of the metals.

Graduate student Joung Eun Yoo and other members of Loo’s laboratory began determining how higher-mass versions of polymer acid improve the plastic’s conductivity when the two materials are combined. So far, they have learned that the higher mass acids attach to the plastic in longer chains, and induce a less-ordered internal structure (crystallinity) within the plastic.

“Understanding how the structure of this polyaniline material changes when its conductivity changes will be crucial for selecting the right material for different consumer applications,” Loo said. She noted that the ability of the plastic to change colours depending on whether it was conductive or not could be especially useful. “Its general versatility could lead to a variety of new consumer products in upcoming years,” she said.; Source: University of Texas at Austin