New cooling fabric could help people beat the dog days of summer

In much of the United States, the worst of the summer heat is upon us. Summer heat causes all sorts of problems for people, the least of which is often extremely expensive electricity bills trying to keep homes and businesses comfortable. In many of the hotter climates, no matter how much you run the air conditioning, it's still hot inside homes.

According to the US Energy Information Administration, air-conditioning and space cooling methods consume about 10% of all electricity in the United States. Researchers have developed a new type of fabric that could help keep people cool in the heat of summer without needing air-conditioning. The fabric transfers heat and allows moisture to evaporate from the skin while repelling water.

The researchers say that cooling off a person's body is much more efficient than cooling an entire room or building. Research has been performed in the past on garments that can help keep the body cool. Still, they had disadvantages, including poor cooling, significant electricity consumption, complex design, high-cost, and complicated manufacturing methods. The new personal cooling fabric can efficiently transfer heat away from the body while being breathable and water repellent, all with an easy manufacturing process.

The cooling material is made by electrospinning the polymer polyurethane, a water-repelling version of the polymer known as fluorinated polyurethane, and a thermally conductive filler made of boron nitride nanosheets. The resulting membranes can repel water from the outside and have large enough pores to allow sweat to evaporate from the skin and air to circulate.

The boron nitride nanosheets form a network that conducts heat from an inside source to the outside air. Researchers found in testing that thermal conductivity for the sheets was higher than many other conventional or high-tech fabrics. The material could also potentially be used for solar energy collection, seawater desalination, and thermal management for electronic devices.