Inexpensive, flexible, and lightweight, plastic has become nearly ubiquitous in industrial and consumer products. Still, the material is limited in terms of its use in electronic devices, automotive, and aerospace applications—primarily due to its difficulty dealing with heat.
Plastics are composed of long, often-messy and loosely bound polymer chains that trap heat energy instead of dissipating it. As a result, highly conductive metals are typically used instead of plastic in products and assemblies that experience heat flow.
Researchers at the University of Michigan have found a way to make plastic more effective at transmitting heat. Whereas previous attempts involved painstakingly straightening polymer chains or adding conductive fillers, the new approach offers a recipe for plastic in which polyacrylic acid (PAA) is combined with polyacryloyl piperidine, both plastics. The novel hybrid exhibits hydrogen bonds that are at least 10-times stronger than those of other plastics, improving energy transmission.
"We improved those connections so the heat energy can find continuous pathways through the material,” Jinsang Kim, an associate professor of materials science and engineering at Michigan, said in a press release. "There's still a long way to go, but this is a very important step we made to understand how to engineer plastics in this way. Ten times better is still a lot lower heat conductivity than metals, but we've opened the door to continue improving."
The new finding suggests that consumer and architectural products could one day weigh and cost less, based on the replacement of some metals with polymers. Moreover, PAA could be created from bio-based sources, offering the possibility of a renewable version of the new material.
Blaine Brownell, AIA, is a regularly featured columnist whose stories appear on this website each week. His views and conclusions are not necessarily those of ARCHITECT magazine nor of the American Institute of Architects.