Benzonitrile electropolymerization

In most cases, stability and oxidation potential issues mean that polythiophenes are prepared, studied, and used in non-aqueous media, and the influence of the solvent can be significant. The extent of solvent swelling is determined by polymer-solvent interactions, which can be manipulated both by choice of solvent and introduction of substituents, here in the 3- and 4-positions. Electropolymerization of alkyl-substituted thiophenes provides good examples of the effects one can observe. EQCM (with PBD) measurements of potentiodynamic deposition from acetonitrile benzonitrile (4 1) of poly(didodecylterthiophene) (with the substituents in the 3, 4 - or 3,3"-positions) showed that film deposition occurred primarily during the reductive half-cycle, in the form of short chain oligomers of the... 

Different monomers have different requirements for the solvent for electropolymerization. For thiophene derivatives the most common solvents are acetonitrile, nitrobenzene, propylene carbonate, and benzonitrile. The solvent should be as anhydrous as possible. 

Subramanian and Garg report the electro-initiated polymerization of benzo-nitrile to yield a linear conjugated polymer by an anionic mechanism. Benzonitrile has been copolymerized electrochemically with phenyl acetylene. Simionescu has also investigated the electropolymerization of acetylene derivatives. ... 

Yoshino et al. [320] reported the successful electropolymerization of selenophene in 1983. Selenophene has been electropolymerized in a small number of solvent/electrolyte systems, with the best results being achieved using benzonitrile/LiBF4 [321]. For selenophene the conditions for deposition are even worse than for thiophene since oxidation is more difficult and overoxidation dominates. Electroactive polymer chains are short (pd = approximately 10) and conductivity is low (approximately 10 S cm ) [322]. 

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