Main Characteristics of Redox Polymers

The charge percolation by electron hopping is necessarily coupled to ion migration inside the coating, as required by fulfillment of electroneutrality. Some important conclusions concerning the conductivity of the coating can be drawn either fi om impedance spectra or by d.c. conductivity measurements (two-band electrode). Necessary condition for the material to be conductive is that it is polarized at potentials close to E° of the redox couple inside the RP. At similar potentials, in fact, meaningful concentration values of both redox forms are present in the RP. This restriction has been experimentally verified for a modified electrode 

Seeber et al., Functional Materials in Amperometric Sensing, Monographs in Electrochemistry, DOI 10.1007/978-3-662-45103-8 3 

Different results are gained when, for instance, an oxidizable species is present in the solution and the potential of the redox couple in the RP at the depositlsolution 

The density of redox centers within the polymer mass, i.e., the redox loading , is a fiuther meaningful feature. This holds from the viewpoint both of the probability of actual occurrence of redox reaction with the species in solution that enter the deposit, and of the steric and flexibility conformational characteristics of the coating mass as a whole. Finally, it is evident that different behaviors, and consequently different properties, are exhibited in different solvent media, i.e., depending 

---