Polyelectrolyte conductance polystyrene sulfonate

A different method of S3mthesizing polyanUine was reported [77]. It uses an enzyme, horseradish peroxidase, in the presence of hydrogen peroxide to polymerize aniline. To prevent reactions at the ortho positions of the phenyl rings that yield insoluble branched materials, a polyelectrolyte template, like sulfonated polystyrene, was used. The polyelectrolyte aligns the monomers, dopes the polyaniline to the conducting form, and forms an irreversible complex with the polyaniline to keep it water-soluble [77]. The conductivity of the complex increases with increasing polyaniline to sulfonated polystyrene molar ratios. Conductivities of0.005 S/cm are obtained with the pure complex and increase to 0.15 S/cm after additimial doping by exposure to HCl vapor [77]. 

Ionic conductivity can be found in polyelectrolytes such as the salts of polyacrylic acid, sulfonated polystyrene or quaternized polvamines (ion-exchange resins). When dry, these materials have low conductivities. However, in tiie presence of small amounts of polar solvents or water—some of these polyelectrolytes are somewhat hygroscopic electrical conductivity can be observed. The currents are earned by ions (protons, for instance). Such systems can only be used in cases where very small currents are expected. Large currents would result in observable electrochemical changes of the materials, In applications as antistatic electricity coatings, conductivities of 10-b ohm-1 cm-1 are sufficient,... 

Few studies have been conducted heretofore on sulfonated ionomers in solvents which can be considered relatively polar, as defined by a high dielectric constant. A recent study (13) on acrylonitrile-methallyl sulfonate copolymers in dimethyl-formamide is a notable exception. S-PS is readily soluble in a wide variety of solvents, some of them exhibiting rather high values of dielectric constant, such as dimethylformamide (DMF) or dimethylsulfoxide (DMSO). The reduced viscosity-concentration behavior of sulfonated polystyrene is markedly different in polar solvents from that in nonpolar-solvent systems. Typically there is a marked upsweep in reduced viscosity at low polymer concentrations and clearly a manifestation of classic polyelectrolyte behavior. ( 7)... 

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