Cool textiles to beat the heat

Air-conditioned buildings bring welcome relief to people coming in from the heat. But creating that comfort comes with a cost to our wallets and the environment in the form of increased energy bills and greenhouse gas emissions. Now researchers report in ACS Nano the development of a new material for clothing that we could one day don as our own personal cooling unit, without any external energy needed to power it.

Functionalized clothes have become the norm in recent years. We now have moisture-wicking and smell-proof athletic gear, and shirts and tops coated with a chemical layer that blocks ultraviolet rays. Clothes that help cool us down, however, have been harder to achieve. So far, such attempts have resulted in materials that incorporate bulky components, require a lot of energy or are expensive. Liangbing Hu and colleagues at University of Maryland College Park wanted to see if they could come up with a more practical option. The researchers combined boron nitride — a material that transfers heat — and polyvinyl alcohol to create a nanocomposite fiber that can be 3-D printed and woven into fabric. Testing to simulate the material on skin showed that the composite is 1.5 to 2 times more efficient at moving heat away from the body when compared to pure polyvinyl alcohol or cotton fabrics, respectively. Making clothes with the nanocomposite thread could help keep wearers comfortable and reduce the need to cool entire buildings, the researchers say. The authors acknowledge funding from the U.S. Office of Naval Research - Young Investigator Program, the Advanced Research Projects Agency-Energy (ARPA-E), the U.S. Department of Energy and the China Scholarship Council. "Three-Dimensional Printed Thermal Regulation Textiles"