Intermolecular Electron Transfer in Low-Molecular-Weight Polyaniline Models Associating on Protonation by Amphiphilic Acid in Organic Solvent

Abstract

Protonation of N-(4-aminophenyl)-N-{4-[(4-aminophenyl)imino]-2,5-cyclohexadien-1-yliden}-1,4-benzediamine and N-[4-(dimethylamino)phenyl]-N-(4-{[4-(dimethylamino)phenyl]imino}-2,5-cyclohexadien-1-ylidene)amine as trianiline models of polyaniline emeraldine base (PANI-EB) with dodecylbenzenesulfonic acid (DBSAH), a typical organo-soluble acidic dopant, in chloroform and 1-methyl-2-pyrrolidinone solutions, and also interaction of the resulting products with distearyldimethylammonium chloride (DDAC) as a potential dedoping agent were studied at ambient temperature by UV−vis and ESR spectroscopic methods. It has been shown that protonation is followed by intermolecular proton−electron transfer and results in the formation of monoradical cations apparently paired with the counterions which tend to associate even in rather dilute chloroform solutions and form aggregates characterized by intermolecular electron interchange. These aggregates, however, dissociate on adding an excess of the protonating agent, revea...