Georgia Tech researchers have modified a thermal polymer interface material so that it conducts heat 20 times better than the original polymer and will operate reliably at temperatures up to 200 deg. C. The new thermal interface material could be used to draw heat away from electronic devices.
The researchers harnessed an electropolymerization process to produce aligned arrays of polymer nanofibers on heat sinks and heat spreaders. The material adheres well to devices, potentially avoiding the reliability challenges caused by differential expansion in other thermally-conducting materials, according to the researchers.
“A material like this, which could also offer higher reliability, could be attractive for addressing thermal management issues. This material could ultimately allow us to design electronic systems in different ways,” said Baratunde Cola, an assistant professor at the Georgia Institute of Technology.
Most amorphous polymer materials are poor thermal conductors because their disordered state limits the transfer of heat-conducting phonons. The new interface material is produced from a conjugated polymer, polythiophene, in which aligned polymer chains in nanofibers facilitate the transfer of phonons – but without the brittleness associated with crystalline structures, according to Cola.
Formation of the nanofibers produces an amorphous material with thermal conductivity of up to 4.4 watts per meter Kelvin at room temperature, said Cola. The material has been tested up to 200 C, a temperature that could make it useful for applications in vehicles.
A patent application has been filed on the material. Cola has formed a startup company, Carbice Nanotechnologies, to commercialize thermal interface technologies.
Co-authors of the paper are researchers from Georgia Tech, the University of Texas at Austin and the Raytheon Company. The research, which was supported by the National Science Foundation, was reported March 30 in Nature Nanotechnology.