Imagine a shirt that makes you cooler than regular clothes, without batteries, chemicals, or plastic. That’s precisely what a team of researchers from Tsinghua University did with a new kind of silk fabric engineered at the nanoscale.
According to a study, ‘Sustainable all-silk textiles for personal thermal management,’ published in Nature Sustainability by Xun-En Wu, Yingying Zhang, and colleagues, the researchers have developed a silk nanotextile, or SilkNT, made entirely of silk, without synthetic polymers or toxic additives. In lab tests, skin covered with SilkNT was 4.3°C cooler than skin covered with traditional silk fabric. Maintaining that kind of temperature difference passively through a hot day would be meaningful for anyone who spends time outdoors in summer.
What makes this fabric work differently
According to the same Nature Sustainability study, the fabric is made by twisting together regenerated silk nanofibres and regular silk yarn using a Fermat-spiral twist, a geometric pattern seen in nature, such as the spiral pattern of seeds in a sunflower. This creates a layered, hierarchical structure within the fabric on a microscopic scale.
It’s important architecturally because of how it handles sunlight. According to the study, SilkNT has a solar reflectance of 94.8%, meaning that almost all incoming solar radiation is reflected rather than absorbed as heat. The fabric also has reduced UV absorption, at only 8.19%, which is a significant improvement over normal silk.
