The synthesis and characterization of a methacrylic polymer containing a pendant electroactive TCNQ moiety

The synthesis of poly [2-(7,7,8, 8-tetracyano-p-quinodimethane)- ethylmethacrylate], a polymer containing an electroactive TCNQ group pendant to the polymer backbone, was attempted using two methods. The first approach involved the polymerization of 2-(2,5-dioxocyclohexyl)ethylmethacrylate, which had been prepared via a series of reactions from a monoalkylated cyclohexanedione, which in turn, had been formed by an enamine alkylation reaction, resulting in a highly crosslinked, insoluble polymer which could not be further modified to the target polymer. The second method, involved the treatment of poly(methacryloyl chloride) with an alkoxide resulting in a pre cursor polymer. The precursor polymer was further modified to form a TCNQ-methacrylate polymer having a degree of polymerization near 29. Infrared spectroscopy and elemental analysis indicated that a copolymer comprised of the TCNQ-methacrylic polymer and poly- (methacrylic acid) was actually formed instead of the homopolymer. The copolymer and copolymer intermediates were also analyzed by visible spectroscopy as films. The electrochemical behavior, of the copolymers in solution and as films, was examined using cyclic voltammetry. The copolymer intermediates showed little or no evidence of electroactivity, while the TCNQ-copolymer, on the other hand, exhibited an electrochemical response. The TCNQ-copolymer was further studied in aqueous solution at various pH's. The electro chemical results for the TCNQ-copolymer suggested that the carboxylic acid derivative was influencing the voltammetry resulting in quasi-reversible behavior.