Scientists have developed a simple metallic coating treatment for clothing or wearable textiles which can repair itself, repel bacteria from the wearer and even monitor a person’s electrocardiogram (ECG) heart signals.
Researchers from North Carolina State University, South Korea and Flinders University in South Australia say the conductive circuits created by liquid metal (LM) particles can transform wearable electronics and open doors for further development of human-machine interfaces, including soft robotics and health monitoring systems.
The breathable electronic textiles have special connectivity powers to “autonomously heal” themselves, even when cut, according to the U.S. team. When the coated textiles are pressed with significant force, the particles merge into a conductive path, which enables the creation of circuits that can maintain conductivity when stretched, the researchers report.
“The conductive patterns autonomously heal when cut by forming new conductive paths along the edge of the cut, providing a self-healing feature which makes these textiles useful as circuit interconnects, Joule heaters and flexible electrodes to measure ECG signals,” says Flinders University medical biotechnology researcher Dr. Khanh Truong, senior co-author of an article in Advanced Materials Technologies.
“Evenly coated textiles remain electrically insulating due to the native oxide that forms on the LM particles. However, the insulating effect can be removed by compressing the textile to rupture the oxide and thereby allow the particles to percolate,” Truong says. “This enables the creation of conductive circuits by compressing the textile with a patterned mold. The electrical conductivity of the circuits increases by coating more particles on the textile.”
The LM-coated textiles also offer effective antimicrobial protection against Pseudomonas aeruginosa and Staphylococcus aureus. This germ repellent ability not only gives the treated fabric protective qualities but prevents the porous material from becoming contaminated if worn for an extended time or put in contact with other people.