Chalk-coated textiles cool in urban environments

Researchers Evan D. Patamia, Megan K. Yee and Trisha L. Andrew created a polymer-mineral coating for commercial fabrics and presented preliminary assessments of the coating's cooling effect at ACS Fall 2024, a meeting of the American Chemical Society.

Now, the researchers confirm that their treated polyester poplin fabric could keep a person up to 15 F cooler than untreated polyester. Additionally, they have expanded the testing environments to four outdoor urban settings, including areas with materials that absorb and emit the sun's heat. Observations made during hot, cloudless days indicate that treated polyester cooled the air underneath the fabric regardless of the environment:

• Open grass field: averaging 6 F below ambient air temperature.
• Concrete-paved alley between buildings: averaging 3 F below ambient.
• Asphalt-paved parking lot: averaging 1 F below ambient.
• Open concrete veranda: averaging 3 F below ambient.

The researchers say their expanded results show the potential of their coated fabrics to provide energy-free cooling for pedestrians and cyclists in urban environments.

The authors acknowledge support from an Interdisciplinary Research Grant from the College of Natural Sciences at the University of Massachusetts Amherst.