New polymer can boost solar power use

The use of solar power could soon become a lot more popular as researchers have created a radical polymer called PTMA, which is about 10 times more electrically conductive than common semi-conducting polymers.

The PTMA is in a class of electrically active polymers that could bring inexpensive transparent solar cells; anti-static and anti-glare coatings for cell phone displays; anti-static coverings for aircraft to protect against lightning strikes; flexible flash drives; and thermo-electric devices, which generate electricity from heat.

"It is a polymer glass that conducts charge, which seems like a contradiction because glasses are usually insulators," said Bryan Boudouris, an assistant professor of chemical engineering at Purdue University in the US.

Polymers are strings of molecules with a central backbone and may contain side chains called "pendant groups" that dangle from the central structure.

In radical polymers, it is these pendant groups that allow charge to be transported, conducting current.

To create the radical polymer, the researchers used a procedure called de-protection, which involves replacing a specific hydrogen atom in the pendant group with an oxygen atom, converting it into a so-called radical group.

"We just finally studied de-protection in a way others had not, to learn how it affects the electronic properties of the radical polymers," Boudouris pointed out.

"Radical polymers have seen commercial use in new types of batteries. However, finding widespread practical applications for the polymers will require increasing the conductivity another 100 to 1,000 times," Boudouris added.

The findings appeared in the journal Macromolecules.