In the pursuit of creating a cooling fabric, researchers have developed a durable chalk-based coating that can lower air temperatures underneath treated fabric by up to 8 degrees Fahrenheit. This new innovation aims to provide relief for those who spend time outdoors during the scorching heat of summer, such as athletes, landscapers, and beachgoers. Traditional cooling textiles rely on boutique fibers or complex manufacturing processes, but this chalk-based coating offers a more accessible and environmentally friendly solution.
The research team, led by chemist and materials scientist Trisha L. Andrew, utilized a technique called chemical vapor deposition (CVD) to apply a polymer coating onto fabric in a simple and efficient manner. By incorporating calcium carbonate and barium sulfate into the polymer layer, the researchers were able to enhance the fabric’s ability to reflect both ultraviolet (UV) and near-infrared (near-IR) light. This innovation draws inspiration from historic practices of using crushed limestone-based plasters to keep houses cool in sunny locations.
The process involved treating small squares of fabric with a poly(2-hydroxyethyl acrylate) layer and repeatedly dipping them into solutions containing calcium and barium ions, as well as carbonate and sulfate ions. By adjusting the number of dipping cycles, the researchers were able to control the size distribution of the particles on the fabric surface, optimizing their light-reflective properties. Outdoor testing demonstrated that the treated fabric achieved a noticeable cooling effect, with air temperatures underneath the fabric registering up to 8 degrees Fahrenheit cooler than the ambient temperature.
To ensure the durability of the mineral-polymer coating, the researchers subjected the fabric to simulated laundry conditions and found that the cooling ability remained intact. The team is now working on scaling up the CVD process for larger fabrics, with the potential to commercialize this technology on a pilot scale. This development could provide a cost-effective and practical solution for creating cooling textiles that can be applied to a wide range of commercially available fabrics, offering a way to keep individuals comfortable in extremely hot environments.
The unique aspect of this technique lies in its versatility and accessibility, allowing for the creation of cooling fabrics without the need for additional power sources. This innovation could be particularly beneficial for individuals in hot climates or those who struggle to stay cool outdoors. The research was funded by the U.S. National Science Foundation, and Trisha L. Andrew is actively involved in commercializing the polymer coating process. Overall, this chalk-based coating represents a promising advancement in the field of cooling textiles, offering a sustainable and effective solution for enhancing comfort in high-temperature environments.
