by While the field of stretchable electronics is promising, assembling the components of such devices can be difficult. A new connector that stretches between the components and connects them to each other in a matter of seconds is intended to remedy the situation.
As things stand, the different parts of stretchable electronic devices (such as soft-bodied robots or wearable sensors) are often glued directly together. Unfortunately, electrical signals cannot travel through the adhesive. Also, if these parts are pulled in opposite directions, the bond of the adhesive will soon break.
In search of a better-performing alternative, an international team of scientists led by Prof. Chen Xiaodong from Nanyang Technological University in Singapore developed a ribbon-like connector called BIND (BIphasic, Nano-dispersed Interface).
It consists primarily of a soft thermoplastic already widely used in stretchable electronics known as styrene-ethylene-butylene-styrene. Embedded in the thermoplastic matrix are electrically conductive nanoparticles made of gold or silver.
When users assemble stretchable electronic devices, they simply push each end of a BIND connector onto the circuit board etc. in each of the two components – the ends securely attach to these items in just 10 seconds. The connector can then be stretched up to seven times its relaxed length without breaking. It also continues to transmit a robust electrical signal between components while being stretched up to 2.8 times its normal state.
In addition, a standard peel strength test showed that the two ends of the connector (which are connected to the connected components) have 60 times higher bond strength than traditional connecting adhesives.
The technology has already been successfully tested on monitoring devices attached to rats and human skin, in the latter case measuring the electrical activity of arm muscles even underwater.
“These impressive results prove that our interface can be used to build highly functional and reliable wearable devices or soft robots,” said Dr. Jiang Ying of Nanyang. “For example, it can be used in high-end wearable fitness trackers, where users can stretch, gesture, and move at will without affecting the device’s ability to capture and monitor their physiological signals.”
A paper on the research – which also involved Stanford University scientists; Shenzhen Institute of Advanced Technology; Agency for Science, Technology and Research (A*STAR); and the National University of Singapore – was recently published in the journal Nature.
Source: Nanyang Technical University
