We describe the preparation of solution-processible hybrid polymers, consisting of a polythiophene main chain and randomly distributed alkyl and oligoaniline side groups. The proposed procedure involves three steps:  copolymerization of alkyl- and ester-group-substituted thiophenes to give the precursor polymer, followed by the hydrolysis of the pendant ester groups and aniline tetramer grafting through an amidation reaction. The proposed method is more versatile than previously used copolymerization procedures because higher tetraaniline grafting levels can be obtained. The postfunctionalized polymer is electrochemically active both in its oligoaniline part and in its conjugated polythiophene main chain. As shown by complementary voltammeric and UV−vis−NIR and Raman spectroelectrochemical studies, the polymer can be electrochemically doped selectively in its side oligoaniline chains or globally in the main chain as well as in the side chains. Selective side-chain doping can also be achieved chemically through protonation of the grafted oligoaniline groups in their semi-oxidized state. Doping with FeCl3 is global and involves the oxidation of the main chain and Lewis acid complexation of the side chains, as shown by Mössbauer spectroscopy.

New processable, electroactive, alternate copolymers consisting of dialkylbithiophene units and oligoanilinethiophene units have been prepared by post-polymerization functionalization of a specially prepared precursor polymer, namely poly [(4,40-dioctyl-2,29:59,20-terthiophene-39-yl)ethyl acetate], carried out via its hydrolysis and consecutive branching aniline dimer or tetramer through the amidation reaction. The precursor polymer is interesting by itself because it gives a very clear spectroelectrochemical response over a very narrow potential range. The proposed method enables the preparation of regiochemically better defined alkylthiopheneoligoanilinethiophene copolymers with higher content of oligoaniline side groups as compared to previously used methods. Cyclic voltammetry investigations combined with UV-vis-NIR, EPR and Raman spectroelectrochemistry show that both the oligoaniline side groups and poly(thienylene) main chain are electrochemically active. Significant differences for the side group electrochemistry are observed in acidified and nonacidified electrolytes making the prepared new copolymer a good candidate for electrochromic applications in diversified electrolytes.