ELECTROCHEMISTRY OF CARBAZOLYLALKYL SUBSTITUTED POLYSILOXANES

Carbazolylalkyl-substituted polysiloxanes undergo anodic oxidation to give insoluble electrode supported cross-linked films containing dicar bazolyl groups. The electrochemistry of the immobilized dicarbazolyls can be addressed and the electrochemical switching between the coloure d (oxidized) and colourless (reduced) states forms the basis of an ele ctrochromic display. Cyclic voltammetry suggests a model in which virt ually all of the pendant carbazole groups are converted into dicarbazo lyls. The model is consistent with observation of a range of polymers, and analogous oligomers, and contrasts with earlier reports on the sa me type of material.