Scientists Have Developed Phase Change Fabrics That Can Rise And Fall In Temperature

According to foreign media reports, scientists have recently developed a new kind of textile that can not only keep wearers warm in cold environments, but also cool them down when the weather gets hot. This experimental material was developed by a team led by Professor Tao Guangming of Huazhong University of Science and Technology. Its preparation method is: firstly, the silk and chitosan are freeze spun to form fibers with porous microstructure – by the way, chitosan is a highly practical natural compound found in crustacean shells.

　　 Next, the pores in the fiber are filled with polyethylene glycol (PEG), a phase change material, which is a solid when hot and a liquid when cold. Finally, an organic polymer called polydimethylsiloxane is coated on the fiber to prevent PEG from leaking out in liquid state.

It is said that the obtained thread has strength, elasticity and waterproofness. The test method is to interweave them to form pieces of material, and then sew them on a traditional polyester glove worn by a volunteer.

When the person places the gloved hand in a space heated to 122 º F (50 º C), PEG will melt into liquid – absorbing ambient heat as well as surrounding heat – thus cooling the skin under the patch. However, once volunteers move their hands into a space cooled to 50 º F (10 º C), PEG will solidify and release stored heat, warming the skin.

　　 Scientists say that this manufacturing process can be mass produced, and it should be relatively easy to integrate this material into the existing textile industry.

The paper on this research was recently published in the Journal of American Chemical Society Applied Materials and Interfaces.