Changing the texture of plastics on demand
By Darren Quick
March 15, 2012
Imagine a pair of rubber gloves whose surface texture could be altered on demand to provide more grip for climbing. Or maybe gloves with "fingerprints" that can be changed in the blink of an eye. They are just a couple of the many potential applications envisioned by researchers at Duke University for a process they have developed that allows the texture of plastics to be changed at will.
The new process follows on from the earlier work of Xuanhe Zhao, assistant professor of mechanical engineering and materials science at Duke’s Pratt School of Engineering, in which he was able to capture on video (see below) how polymers react to increasing voltages by first creasing and then developing large craters. Now, by applying specific voltages, Zhao and his team have been able to achieve the controlled alteration of the texture of plastics over large and curved surface areas.
“This new approach can dynamically switch polymer surfaces among various patterns ranging from dots, segments, lines to circles,” said Qiming Wang, a student in Zhao’s laboratory and the first author of a paper detailing the team's findings. “The switching is also very fast, within milliseconds, and the pattern sizes can be tuned from millimeter to sub-micrometer.”
“The changeable patterns we have created in the laboratory include circles and straight and curved lines, which are basic elements of fingerprints,” Zhao said. “These elements can be dynamically patterned and changed on a glove surface that covers fingertips.”
For the more law abiding, Zhao adds, “however, the same technology can produce gloves with on-demand textures and smoothness tuned for various applications, such as climbing and gripping. Furthermore, surfaces capable of dynamically changing patterns are also useful for many technologies, such as microfluidics and camouflage.”
The teams results were published online in the journal Advanced Materials.
Source: Duke University