Once cotton gets wet, it pulls heat from your body. This is helpful when you’re exercising or outside on a hot day but dangerous in the bitter cold. Now, researchers reporting in ACS Energy Letters have created an ultralight synthetic fiber material with a cotton-like fluffiness that also repels water. The prototype fabric outperformed regular cotton in both retaining heat in the cold and releasing heat at room temperature.
According to Quan Shi, a corresponding author of the study, “Inspired by the fluffy structure of cotton, we created a new material that is ultralight and flexible. It keeps you warm in the cold better than cotton or commercial synthetic insulations, while also prevents you from getting too hot at room temperature.”
To improve natural fibers’ ability to regulate heat in extreme cold, researchers have proposed coating the fibers with phase-change substances. These substances harden and melt as the air temperature changes and then trap or release heat, respectively. But current phase-change coatings stiffen fabrics and sometimes leak onto the wearer. So, Shihui Zhang, Zhihua Zhang, Quan Shi and colleagues integrated a phase-change material into synthetic fibers that the team designed to mimic the soft structure of cotton.
The researchers created a network of polymer fibers dotted with microscopic capsules of a phase-change hydrocarbon. Their lightweight material could be formed into cotton-like balls or flat fabric.
