A team of scientists from the US has developed a simple metallic coating treatment for clothing or wearable textiles which can repair itself, repel bacteria, and even monitor a person’s electrocardiogram (ECG) heart signals.
THE RESEARCHERS: According to researchers from North Carolina State University, Flinders University and South Korea, led by Professor Michael Dickey, the conductive circuits created by liquid metal (LM) particles can transform wearable electronics.
- This open doors for further development of human-machine interfaces, including soft robotics and health monitoring systems.
- The paper, 'Liquid Metal Coated Textiles with Autonomous Electrical Healing and Antibacterial Properties' by Jiayi Yang, Praneshnandan Nithyanandam, Shreyas Kanetkar, Ki Yoon Kwon, Jinwoo Ma, Sooik Im, Ji-Hyun Oh, Mohammad Shamsi, Mike Wilkins, Michael Daniele Tae-il Kim, Huu Ngoc Nguyen, Vi Khanh Truong and Michael D Dickey has been published in Advanced Materials Technologies.
‘BREATHABLE’ ELECTRONIC TEXTILES: The ‘breathable’ electronic textiles have special connectivity powers to ‘autonomously heal’ itself even when cut.
- 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 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.
- The technique involves dip-coating fabric into a suspension of LM particles at room temperature.
- 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.
- This enables the creation of conductive circuits by compressing the textile with a patterned mould. The electrical conductivity of the circuits increases by coating more particles on the textile.
- The LM-coated textiles offer effective antimicrobial protection against Pseudomonas aeruginosa and Staphylococcus aureus.
- This germ repellent ability not only gives the treated fabric protective qualities but also prevents the porous material from becoming contaminated if worn for an extended time, or put in contact with other people.
- The particles of gallium-based liquid metals have low melting point, metallic electrical conductivity, high thermal conductivity, effectively zero vapor pressure, low toxicity and antimicrobial properties.
- LMs have both fluidic and metallic properties so show great promise in applications such as microfluidics, soft composites, sensors, thermal switches and microelectronics.
- One of the advantages of LM is that it can be deposited and patterned at room temperature onto surfaces in unconventional ways that are not possible with solid metals.
WHAT THEY SAID:
The textiles could be used in things like antimicrobial hospital bed covers and patient clothing, monitoring heart rate as well as preventing infections. The next thing is to, with planning, integrate them into actual textiles.
— Khan Truong
Researcher (Senior co-author)
Flinders University
