Tuckerfan
05-17-2005, 07:06 PM
He thinks it'll have great biomedical uses. (http://www.engr.utexas.edu/news/articles/20050510812/index.cfm)Loo, an assistant professor of chemical engineering, will use the three-year, $264,000 award to seek a 10-fold increase in the conductive ability of the plastic. That enhancement might be enough for manufacturers to begin considering polyaniline-based wires for products that include: electronic display screens that can be rolled up after use, clothing with polyaniline woven into it that changes color when exposed to a harmful chemical, and implantable medical devices that release a drug when someone’s body temperature changes.
“Using this material to develop biodevices would be especially nice,” Loo said, “because polyaniline appears to interact well with living cells.”
Plastics involve long chains of carbon atoms, which traditionally are molded into the shell of hair dryers and other devices because plastics transfer heat and electricity poorly. Scientists make plastics electrically conductive through a process called chemical doping where another molecule that can donate charge to the plastic is added. Loo’s process is different in that the molecule that is added is a polymeric acid, which is larger than previous molecules tested.
Determining the right ratio of the two starting components needed to achieve good conductivity will be part of Loo’s general grant efforts to better understand how the final polyaniline’s features are influenced by the reaction processes involved in creating modified versions of it.
“The question is, ‘How do the nanoscale features of this plastic affect its macroscopic electrical properties,’ ” Loo said. “That’s important information to gain.
“When you make a device in the laboratory, it’s OK if it works one time, but you want the material’s properties to be reliable and reproducible before you can even think about big applications.”
Using polymeric acid also increases polyaniline’s ability to dissolve in water. Previous attempts to dope polyaniline to become metal-like failed because the final product would not dissolve in any solvents, which is considered crucial to making inexpensive products with it.
“Using this material to develop biodevices would be especially nice,” Loo said, “because polyaniline appears to interact well with living cells.”
Plastics involve long chains of carbon atoms, which traditionally are molded into the shell of hair dryers and other devices because plastics transfer heat and electricity poorly. Scientists make plastics electrically conductive through a process called chemical doping where another molecule that can donate charge to the plastic is added. Loo’s process is different in that the molecule that is added is a polymeric acid, which is larger than previous molecules tested.
Determining the right ratio of the two starting components needed to achieve good conductivity will be part of Loo’s general grant efforts to better understand how the final polyaniline’s features are influenced by the reaction processes involved in creating modified versions of it.
“The question is, ‘How do the nanoscale features of this plastic affect its macroscopic electrical properties,’ ” Loo said. “That’s important information to gain.
“When you make a device in the laboratory, it’s OK if it works one time, but you want the material’s properties to be reliable and reproducible before you can even think about big applications.”
Using polymeric acid also increases polyaniline’s ability to dissolve in water. Previous attempts to dope polyaniline to become metal-like failed because the final product would not dissolve in any solvents, which is considered crucial to making inexpensive products with it.