Researchers Wrap Nanotubes Around Rubber Core Sparking a
Creation That May Lead to Artificial Muscles, Sensors
(July 23, 2015) An
international research team based at The University of Texas at Dallas has made
electrically conducting fibers that can be reversibly stretched to over 14
times their initial length and whose electrical conductivity increases 200-fold
when stretched.
The research team is using the new fibers to make artificial
muscles, as well as capacitors whose energy storage capacity increases about
tenfold when the fibers are stretched. Fibers and cables derived from the
invention might one day be used as interconnects for super-elastic electronic
circuits; robots and exoskeletons having great reach; morphing aircraft;
giant-range strain sensors; failure-free pacemaker leads; and super-stretchy
charger cords for electronic devices.
In a study published in the July 24 issue of the journal
Science, the scientists describe how they constructed the fibers by wrapping
lighter-than-air, electrically conductive sheets of tiny carbon nanotubes to
form a jelly-roll-like sheath around a long rubber core.
The new fibers differ from conventional materials in several
ways. For example, when conventional fibers are stretched, the resulting
increase in length and decrease in cross-sectional area restricts the flow of
electrons through the material. But even a “giant” stretch of the new
conducting sheath-core fibers causes little change in their electrical
resistance, said Dr. Ray Baughman, senior author of the paper and director of
the Alan G. MacDiarmid NanoTech Institute at UT Dallas.