New material for stretchy electronics inspired by nature

Tue Dec 11, 2012 11:14am EST
 

By Chris Wickham

LONDON (Reuters) - Scientists in Switzerland have come up with a material mimicking the way tendons connect to bones, which could speed the development of stretchy, wearable electronic devices.

The stretchable electronics industry is in its infancy but devices that are able to flex without breaking could revolutionize devices from smartphones and solar cells to medical implants.

Futurists have long predicted clothes with sensors that monitor the vital signs of the wearer, or smartphones and screens woven into the fabric of shirts or jackets.

But while circuits and wiring are quite happy on rigid surfaces like those in a tablet computer, they break easily when combined with materials that stretch.

"You have two materials with very different mechanical properties," Andre Studart, a researcher at the Swiss Federal Institute of Technology in Zurich, told Reuters. "The challenge is to bridge these different properties."

Studart and his team have overcome the problem with a stretchy material made from polyurethane that contains "islands" stiff enough to house and protect delicate circuits.

While the soft part can stretch by 350 percent, the stiff regions created by impregnating the material with tiny platelets of aluminum oxide and a synthetic clay called laponite, hardly deform and can protect the electronics.

The material, presented in research published in the journal Nature Communications, is made from bonded layers and because the concentration of the platelets is gradually increased, the junction between the stretchy and stiff parts is also durable.   Continued...

 
A stretchable material containing squared stiff islands for the protection of brittle electronic devices is pictured in this handout photo. Studart/Handout