Molecular dynamics in plastic conducting compounds of polyaniline

Polyaniline (PANI) has been protonated (doped) with phthalosulfonic acid and sulfosuccinic acid diesters. Freestanding films exhibiting high electrical conductivity and good plasticity were obtained. The dynamics of protons attached to the alkyl chains of these "plastdopants" has been studied by using quasielastic neutron scattering techniques. A glass transition was thus detected at a temperature corresponding to that measured by DSC. This dynamical transition occurred in the temperature range, in which both a thermochromism and an insulator-metal electrical transitions (IMT) were also observed. The local diffusive motions of these protons are described in terms of diffusion within spheres whose temperature dependent radii are distributed in size along the alkyl chains.