What if our clothes could better absorb our sweat and use it for more than just cooling down our bodies? At the National University of Singapore (NUS), researchers have developed a high-tech film that can absorb and store moisture from sweat much more efficiently than conventional materials that use that moisture to generate small amounts of electricity. This electricity then can be used to power wearables such as fitness trackers.
The new film is designed to accelerate sweat evaporation, absorbing the moisture from sweat six times faster, and hold 15 times more moisture than existing materials.
The film is made mainly from two chemicals, cobalt chloride, and ethanolamine, which are known for their highly effective water-absorbing properties. These are then coated by membranes made from PTFE (polytetrafluoroethylene), a material that’s waterproof, breathable, and flexible.
The idea is to incorporate the resulting material into shoe insoles or underarm pads to keep wearers drier and more comfortable, which could be particularly useful in the hot summer months or during exercise.
What’s also cool (no pun intended) about the material, is that it can change color upon absorbing moisture, starting off blue, then turning purple, and eventually pink — which can be a handy indicator of the degree of moisture absorption. By exposing the material to sunlight, the water it holds quickly evaporates, and the inventors say the film can eventually be reused over 100 times.
But that’s not all. In another experiment, the team used the new film to create a material that generates energy by absorbing moisture. Featuring eight electrochemical cells, the material was able to generate enough energy to power an LED. And while that’s obviously not a huge amount of power, it does prove that low-power wearable electronic devices, such as fitness trackers, could one day run on sweat.
