3:30 PM - SB10.05.06
Engineering Flexible Multi-Scale Materials for Sustainable Multi-Functional Clothes and Wearables
Massachusetts Institute of Technology1
The ever-growing demand for lightweight portable high-tech devices is evolving into an even more challenging demand for fully wearable devices integrated into clothes. To meet this demand, the emerging wearable optical technologies must combine multiple functionalities, including visual effects, communications features, thermoregulation to maintain personal comfort level, and even self-cleaning and microbial treatment by sunlight. These technologies often require portable or renewable power sources to operate—and the lack of cheap, long-lasting and lightweight sources has proved a big hurdle to wider adoption. Finally, new technologies must meet the global demand for tighter environmental standards to reduce energy and water use and waste during the fabrication process as well as throughout the garments life cycle. They must also provide a clear pathway for recycling and re-using the materials into new fabrics and wearables.
We develop multi-functional materials for wearable technologies, which combine a variety of optical, thermal, mechanical, and biological functionalities, and meet high standards for energy and water saving and sustainability. I will discuss the engineering approaches used in designing and fabricating woven and knitted fabrics out of polyethylene fibers to achieve either passive cooling without breaking a sweat or passive heating without the use of uncomfortable metal films. I will then show how the fiber micro-structuring can be combined with nano-scale engineering via embedding a variety of nano-inclusions to combine thermoregulation-by-radiation-control functionality with structural coloring, unique lateral heat conduction properties, and anti-microbial resistance of new textiles. We embed colorants and anti-microbial agents into fibers and films during their fabrication, which does not require significant water usage, in stark contrast with the standard industrial processes that use 200 liters of water to produce 1 kg of textile, and create large amounts of wastewater contaminating the environment. The new textiles also offer excellent water wicking, dirt-resistant, and fast drying functionalities, offering significant energy and water savings for their maintenance, and can be easily recycled at the end of their lifetime.
Finally, I will discuss how the new fabrics can be further enhanced by incorporating other functional wearable elements, including fibers for optical communication, photo-detectors, and flexible, lightweight, round-the-clock energy harvesters capable of operating in the self-powered regime.
Acknowledgements: This work is supported by the US Army Research Office (via the CCDC Soldier Center and the MIT Institute for Soldier Nanotechnologies), Advanced Functional Fabrics of America (AFFOA), MIT International Science and Technology Initiatives (MISTI), and the UNSW-USA Networks of Excellence.
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