Turning Polymer Insulators into Heat Conductors

Polymers with ultrahigh thermal conductivity are essential for various thermal management applications, including microelectronics cooling, energy storage, and conversion. Despite their importance, common polymers are thermal insulators, posing a significant challenge in achieving ideal thermal regulation. Controlling thermal properties and understanding thermal transport mechanisms in polymers remains challenging, partly due to their complex polymer structures. In this talk, I will discuss our recent experimental and theoretical efforts to understand thermal transport properties in polymers, to uncover relationships between these properties and structures, and to turn polymer insulators into heat conductors. Firstly, I will describe transforming polymer (polyethylene) thermal insulators into heat conductors surpassing the thermal conductivity of many metals and ceramics. Secondly, I will discuss the thermal transport properties in conjugated polymers, creating high thermal conductivity in polythiophene 10 times higher than common polythiophene, with potential applications in electronics and optics to mitigate overheating issues. Thirdly, I will present our recent findings on how defects enhance interfacial thermal transport within polymeric materials. Finally, I will conclude by envisioning that a variety of thermal transport puzzles in polymers may be solved through combined experimental and theoretical research efforts.

Yanfei Xu joined the Mechanical & Industrial Engineering Department at the University of Massachusetts Amherst in 2019 as an Assistant Professor. Prior to this, she conducted postdoctoral research at MIT from 2013 to 2018, focusing on transforming polymer insulators into heat conductors. From 2011 to 2013, she contributed to research on printable organic electronics as part of the GENIUS project funded by the European Commission. During this time, she secured Marie-Curie Fellowships with European institutions, including the Max Planck Institute for Polymer Research and the headquarters of BASF SE. She holds a Ph.D. in Chemistry from Nankai University, where she was recognized as one of the "Top 100 Most Influential Scientific Researchers in P. R. China (among all fields)." Her research focuses on advancing the understanding of heat and charge transport mechanisms in polymers, while also developing polymers with potential properties for better electrical and thermal management applications.