Oxireductases in the Enzymatic Synthesis of Water-Soluble Conducting Polymers - Enzymatic Polymerisation - page 5

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Scheme 2 Chemical structure of DBSA ( left ) and DODD ( right ) molecules. (Reprinted with
permission from Rumbau et al. [ 38 ]. c 2007, Elsevier)

Scheme 3 Polymerization mechanism: aniline-DODD interaction and polymerization.

(Reprinted with permission from Rumbau et al. [ 38 ]. c 2007, Elsevier)

The bifunctional DODD molecule, due to the presence of two sulfonic groups in
its structure, shows higher water solubility than monofunctional surfactants such
as DBSA. At acidic pH, sulfonate groups become negatively charged, thereby
increasing the total charge per molecule and, consequently, the solubility. This idea