Self-doped polymers copolymerization

While there are reports of making homopolymers of self-doped polymers (e.g., 2-methoxyaniline-5-sulfonic acid), many derivatized monomers do not polymerize alone to yield their respective homopolymers. For example, if the substituents are bulky (e.g., l-(2-amino)-pronane-3-sulfonic acid or l-(2-amino)-butane-3-sulfonic acid), the homopolymerization is not possible. In these cases, bulky substituent containing monomers need to be copolymerized... 

C. Barbero, R. Koetz, Electrochemical formation of a self-doped conductive polymer in the absence of a supporting electrolyte. The copolymerization of o-aminobenzenesulfonic acid and aniline, Advanced Materials 1994, 6, 577. 

Structural modifications of polyaniline have mainly been exploited to achieve improved processability and environmental stability. In general, the substituted polyanilines can be obtained via oxidative polymerization of the corresponding monomer. However, inductive and steric effects can make such monomers difficult to polymerize [42]. Several substituted polyanilines have been prepared by varying the nature (alkyl, alkoxy, halogen, etc.) and the position (2- vs 3-, 5-positions) of the substituent [24, 27-32, 34, 37, 43, 44]. These studies have shown that regardless of the nature and position of the substituent group, there is an adverse effect on polymerization and the properties of the polymer such as conductivity and electroactivity. To overcome these limitations, various synthetic methods have been developed to prepare self-doped sulfonated polyanilines. These methods involve controlled postpolymerization modifications by synthetic reactions on the whole polymer and copolymerization of less reactive monomers with aniline as described below. 

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