Abstract: The present invention discloses a process for preparing an aqueous solution of self-acid-doped o-sulfonic acid ring-substituted polyaniline, which can be cast into free-standing films. The process involves dissolving a solid o-sulfonic acid ring-substituted polyaniline in an alkaline aqueous solution to form an aqueous solution of an undoped o-sulfonate ring-substituted polyaniline; purifying the aqueous solution of the undoped o-sulfonate ring-substituted polyaniline by subjecting it to a purifying treatment to remove excess alkali therefrom; and contacting the resulting purified aqueous solution with a H.sup.+ -type ion-exchange resin to form an aqueous solution containing a self-acid-doped o-sulfonic acid ring-substituted polyaniline. A suitable water soluble polymer or polymer emulsion can be easily mixed with the aqueous solution containing the self-acid-doped o-sulfonic acid ring-substituted polyaniline to form a polymer blend.

Abstract: The present invention discloses a water-soluble self-acid-doped polyaniline, and its sodium salt, which can be cast into free-standing films from their aqueous solutions. A process for preparing a water-soluble self-acid-doped polyaniline is also disclosed, which comprises reacting a polyaniline with a strong base to convert the amino nitrogen thereof to anionic nitrogen; reacting sultone with the anionic nitrogen to form a side chain alkanesulfonic acid group; doping with protonic acid to form precipitate; dissolving (undoping) the precipitate in an alkaline aqueous solution; removing excess alkali from the alkaline aqueous solution; and contacting the resulting aqueous solution with a H.sup.+ -type ion exchange resin. Moreover, an aqueous solution of the present water-soluble self-acid-doped PAn can be easily mixed with an additional water soluble polymer or polymer emulsion, which can then be cased into a polymer blend film having improved mechanical properties and coupling strength to a substrate.

Abstract: A process for preparing an N-substituted polyaniline comprising the steps of reacting an alkali hydride and a polyaniline having imine bonds, mixing the reaction mixture with an alkyl or alkoxyalkyl halide to generate a polymer, precipitating the generated polymer, and undoping the polymer. The N-substituted polyaniline can be dissolved in organic solvents having low boiling points and can be doped to provide films with a conductivity of 10.sup.-6 to 10.sup.-2 s/cm.

Abstract: The present invention discloses a water-soluble self-acid-doped polyaniline, and its sodium salt, which can be cast into free-standing films from their aqueous solutions. A process for preparing a water-soluble self-acid-doped polyaniline is also disclosed, which comprises reacting a polyaniline with a strong base to convert the amino nitrogen thereof to anionic nitrogen; reacting sultone with the anionic nitrogen to form a side chain alkanesulfonic acid group; doping with protonic acid to form precipitate; dissolving (undoping) the precipitate in an alkaline aqueous solution; removing excess alkali from the alkaline aqueous solution; and contacting the resulting aqueous solution with a H.sup.+ -type ion exchange resin. Moreover, an aqueous solution of the present water-soluble self-acid-doped PAn can be easily mixed with an additional water soluble polymer or polymer emulsion, which can then be cased into a polymer blend film having improved mechanical properties and coupling strength to a substrate.