The effects of LiCl and MgCl2 in the synthesis solution on the kinetics and properties of polyaniline

The effects of salt additions, LiCl and MgCl2, into the aniline-bearing HCl solutions have been studied during the oxidative polymerization with ammonium persulphate. To assess both protonic and ionic effects, LiCl or MgCl2 was added maintaining the chlorine concentration constant. Three polymerization parameters were recorded: T-max, E-max and t(max)(v = 1/t(max)). T-max and v have been correlated with [H+] and [cation]=[H+]. The conductivity as a relevant property of the polymer depends on its preparation history. The present study shows a positive effects of salt additions to the conductivity, which increases following the trend HCl < LiCl < MgCl2 when [Cl-] > 2.0 M.