Plastic magnet

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A plastic magnet is a non-metallic magnet made from an organic polymer. One example is PANiCNQ, which is a combination of emeraldine-based polyaniline (PANi) and tetracyanoquinodimethane (TCNQ). When it was created by researchers at the University of Durham in 2004 it was the first magnetic polymer to function at room temperature.

PANi is a conductive polymer that is stable in air. When combined with the free radical forming TCNQ as an acceptor molecule it can mimic the mechanism of metallic magnets. The magnetic properties arise from the fully pi-conjugated nitrogen-containing backbone combined with molecular charge transfer side groups. These properties cause the molecule to have a high density of localised spins that can give rise to coupling of their magnetic fields. When a polymer magnet is synthesized, the polymer chains need a long time to line up before displaying any notable magnetism.

Plastic magnets could have uses in computer hardware, for example as disc drives and in medical devices such as pacemakers and cochlear implants where the organic material is more likely to be biocompatible than its metallic counterpart.

[edit] External links

• New Scientist article describing discovery
• Naveed A. Zaidi, S.R. Giblin, I. Terry & A.P. Monkman 2004. Room temperature magnetic order in an organic magnet derived from polyaniline. Polymer 45(16): 5683-5689.