Plastics ease nanotube circuits

Plastic electronics promise to enable flexible, inexpensive devices from electronic paper to smart clothing. Researchers developing organic electronic materials have to balance requirements that often conflict: material with good electrical properties, and material that is readily processable.

Researchers from DuPont Central Research and Development and Columbia University have devised a way to make a random, self-assembled network of carbon nanotubes embedded in polymer that preserves the nanotubes' electrical conductivity and is suitable for thermal printing processes.

Carbon nanotubes are rolled-up sheets of carbon atoms that can be narrower than one nanometer in diameter.

The nanotube networks could eventually be used to make large, inexpensive electrical signs and displays, according to the researchers.

The researchers' composite material consists of nanotubes, a conductive polymer that connects the nanotubes to form a highly-conductive network, and a non-conductive, or insulating polymer that forms a film, or matrix, surrounding the interconnected nanotubes. The matrix has no impact on the electrical properties of the nanotube network, according to the researchers.

The material incorporate bundles of nanotubes and could be used to make thin-film transistors for displays. The method could also be used with single nanotubes to yield materials suitable for nanoelectronics applications like nanowires and biosensors, according to the researchers.

Organic electronic applications could be practical in 2 to 5 years, according to the researchers. The work appeared in the August 2, 2004 issue of Applied Physics Letters.