Author: Eanas Aboobaker
Institution: Duke University
Date: February 2010
Did you know that each year, 4.6 million tons of electronic waste finds its way to landfills? This includes tens of thousands of televisions, computers, cell phones, PDAs, and various other consumer electronics. These products frequently end up in landfills because the plastics that are used to make them cannot be remelted or reshaped, and therefore cannot be reused. As a result of the substantial amount of electronic waste disposed annually, there is potential for several harmful chemicals to be released into the air. These pollutants can have damaging effects on both human and environmental health. For instance, it has been reported that lead and mercury found in devices such as computer monitors, cell phones, and batteries can cause irreversible brain damage.
Electronic devices are commonly made from polymers, large molecules composed of many repeating structural units, similar to a train consisting of several identical passenger carts. Depending on the molecules it consists of, a polymer may be hard or brittle, rubbery or rigid, sticky or slippery. These assorted characteristics enable polymers to be effectively used in a broad range of products, including the latest electronic devices. On the other hand, a disadvantage of these polymers is that they are not "self-healing," meaning they cannot be broken down into their repeating structural units to be repaired or reused.
Recently, researchers in the Netherlands have developed a new "self-healing polymer" that can be recycled, which has the potential to reduce the hazardous electronic waste disposal that is threatening the health of our environment. In their study, the research group at the University of Groningen noted that while several attempts to develop a self-healing polymer have been made in the past, those methods have relied on costly chemical reactions that were difficult to carry out on a large scale. However, the method that they used was quicker and more cost-efficient, enabling it to be used on a large scale by manufacturers of electronic devices. In addition, unlike previously developed self-healing polymers, the polymer developed in this study can be melted and remolded without loss of its initial strength. The researchers hope that their findings will set the stage for further research on self-healing materials and ultimately lead to the development of more environmentally friendly electronic products.
References
Zhang, Y, Broekhuis, A., and F. Picchioni. "Thermally Self-Healing Polymeric Materials: The Next Step to Recycling Thermoset Polymers?" Macromolecules 2009 42(6): 1906-1912.
"Electronic Wastes: The Dangers." Hazardous Technical Information Services Bulletin, November 2001.
Author: Eanas Aboobaker
Reviewed by: Jessica Kloss and Yangguang Ou
Published by: Yangguang Ou