three-layered textile made from fabric, plastic and silver nanowires can keep a person several degrees cooler than silk or other cooling materials..
Future city dwellers could beat the heat with clothes made of a new fabric that keeps them cool.
The textile, made of a plastic material and silver nanowires, is designed to stay cool in urban settings by taking advantage of a principle known as radiative cooling – the natural process by which objects radiate heat into space.
The material selectively emits infrared radiation within the narrow band of wavelengths that can escape Earth’s atmosphere. At the same time, it blocks the sun’s radiation and infrared radiation emitted by surrounding structures.
Po-Chun Hsu at the University of Chicago in Illinois and his team designed this material to “try to block more than half of [the radiation] from the buildings and the ground”, he says.
Some cooling fabrics and building materials already rely on this radiative cooling principle, but most of those designs do not account for radiation from the sun or infrared radiation from structures like buildings and pavement. They also assume the material would be oriented horizontally to the sky like panels on a rooftop, rather than the vertical orientation of material in clothes worn by a person.