What Can Dissolve Polypyrrole?
Polypyrrole is quite a rigid polymer (one of the reasons it's a conductive polymer) and it's generally not considered particularly soluble without being derivatized. It seems to be possible to dissolve it somewhat in polar organic solvents if it's been polymerized with a large anion like dodecylbenzenesulfonate, basically reducing the interactions of the chains of polymer, but it loses some of its conductivity when cast into a film. One group has apparently managed to make it water soluble by polymerizing oxidatively with horseradish peroxidase in the presence of a sulfonated polystyrene counterion, which keeps the chain growing linearly along the length of the polystyrene, apparently allowing it to be soluble.