Electrodiffusional Transport in Electroactive Polymer Films

An important feature of the electroactive polymer materials is the presence of two different kinds of mobile charge carriers, electronic and ionic. These polymers constitute mixed conductors. As in the case of ionic transfer phenomena in electrolyte solutions, there are generally two reasons for coupling between fluxes of different charge species. First creation in the concentration gradient of a charged species must be compensated by a redistribution of other components to retain the local electroneutrality of the system. Another factor is an electric field inside the polymer phase whose distribution is adjusted to the fluxes of charged species in a self-consistent way. 

A complete set of equations for nonstationary transport consists of three types of relations 

Balance equations for all mobile components—electronic and ionic Expressions for their fluxes Local electroneutrality coupling 

If there is no transformation of the species inside the polymer phase, the balance equation for electronic or ionic species i in the case of a one-dimensional transport takes the universal form 

Fluxes in charged species are generated by local thermodynamic 

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