Dispersion-induced insulator-to-metal transition in polyaniline

Melt dispersion processing-without solvents or "secondary dopants"-pushes p olyaniline reproducibly to the metallic side of the IM transition, although the undispersed polyaniline is on the insulator side. This is the first ti me that a conductive polymer is found there without applying pressure. The transition to the metallic state is associated with a decrease of the C-6-N -C-6 angle from 166 degrees to 134 degrees.