Protonation and doping behavior of polypyrrole films and powders

Summary form only given. The difference in protonation and charge transfer behavior between polypyrrole(PPy) powders and films doped with ´macromolecular´ acids, such as dodecylsulfonic acid(DS), dodecylbenzensulfonic acid(DBSA), and poly (styrenesulfonic acid) (PSSAc), and ´micromolecular´ acids, such as H/sub 2/SO/sub 4/ and HCl0/sub 4/, were assessed quantitatively by X-ray photoelectron spectroscopic(XPS) technique. PPy-dodecylsulfate films with [N/sup +/]/[Nl ratios >40% can be readily prepared electrochemically. Reprotonation of the 25% deprotonated PPy films(containing 25% =N/sup -/ units) by excess macromolecular acid readily results in complexes with surface [N/sup +/]/[N] ratios substantially above 50%. For deprotonated PPy films loaded with excess micromolecular acids, and deprotonated PPy powders loaded with excess micro- or macromolecular acids, the protonation levels or [N/sup +/]/[N] ratios remain in the order of 25 to 30%. The enhanced charge transfer interaction in PPy-rnacromolecular anion films is probably attributable to the counter-ion induced molecular ´blending´ between the polymer and the dopant.