Poly films doped with iodine

Thin films of poly-l,2-azepines formed by the photopolymerization of phenyl azides exhibit electric conductivities of up to 0.01 S cm upon oxidative doping with iodine or arsenic pen-tafluoride <88JA7209>. 

Linear poly(A/-methyl-3,6-carbazolylen) (64c) has been prepared by the reaction of 3,6-dibromo-9-methylcarbazole (67a) with the Grignard reagent (67b) in the presence of a complex nickel catalyst [436-438], A brittle film of (67c) can be cast from nitrobenzene solution which shows a conductivity, when doped with I2 or NOBF4, as high as 6 S cm . Doping with iodine induces a postpolymerization reaction which increases its molecular weight and improves mechanical stability. 

Conducting polymers that can be molded by conventional melt processes have been made by attaching side groups to the conjugated polymers of Table 11.5. For example, poly(3-octylthiophene) in the undoped state can be molded by compression or injection just like other thermoplastics [14]. When films of this polymer are doped with FeClj, conductivities of over 10 S/cm are measured. Even a blend of 20 parts of the polymer with 80 parts of an ethylene-vinyl acetate copolymer can be doped with iodine to a conductivity of about 1 S/cm. 

Enzymatically synthesized polyphenol derivatives are expected to have great potential for electronic applications. The surface resistivity of poly(p-phe-nylphenol) doped with nitrosylhexafluorophosphate was around 105 Q.4a The iodine-labeled poly(catechol) showed low electrical conductivity in the range from 10 6 to 10 9 S/cm.48 The iodine-doped thin film of poly (phenol- co- tetradecyloxyphenol) showed a conductivity of 10 2 S/cm, which was much larger than that obtained in aqueous 1,4-dioxane.24a The third-order optical nonlinearity (%3) of this film was 10 9 esu. An order of magnitude increase in the third-order nonlinear optical properties was observed in comparison with that prepared in the aqueous organic solution. 

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