Stretchable Electronics to go on Electroactive Polymers
Arla Foods, the largest dairy products company in Europe, has been developing various smart packages including ones that have micropumps that suck down the plastic wrapping back on to cheese to preserve it in the home. Electroactive plastics change shape under the influence of an electric field and another potential application of them would be to make the package of expired food change in texture to warn the partially sighted user.
Micromuscle AB in Sweden is one of several companies developing electroactive polymers. Their products will be used as muscles, locks (for example on packages of hazardous chemicals) and even communication with the partially sighted and others by change of texture, perhaps using changeable Braille. For example, the package could sense that it has been left out for too long and the Braille could change from giving an expiry date to saying EXPIRED DO NOT USE. Micromuscle pumps could be an environmental alternative to aerosols, if powerful enough printed batteries become available.
In most cases, very high volume use will call for the low cost and durability of printed electronics but those circuits must be able to stretch if they are to be deposited on electroactive polymers. So far, printed organic inks have been the nearest to meeting such a requirement and they are rarely stretchable enough.
In 2007, more suitable flexible electronic structures with the potential to bend, expand and manipulate individual electronic devices are being developed by researchers at the US Department of Energy’s Argonne National Laboratory and the University of Illinois at Urbana-Champaign in the USA. The researchers say that these could find applications as sensors and electronic devices that can be integrated into artificial muscles or biological tissues. In addition to a biomedical impact, flexible electronics are important for energy technology as flexible and accurate sensors for hydrogen.