Self-doped polymers phosphonate

The self-doped polymer, poly A-(4-sulfophenyl)aniline 10, bearing a sulfonated substituent on each of its N centers, has also been prepared by oxidizing the relevant monomer with (NH4)2S208 in aqueous HC1.146 147 Phosphonic acid substituents can also be utilized to generate self-doping PAn s, as illustrated by the oxidation using... 

Progressive neutralization with NaOH gave the sodium salt analogs shown in Figure 20.56. Neutralization of the most acidic protons produced the hemi-sodium salt of the polymer for which 39% of N-atoms were oxidized. It was reported that protonation occurred solely by internal proton transfer. Further neutralization to the monosodium salt resulted in 26% self-doping. Upon further titration, neutralization was complete, resulting in the disodium salt, for which the phosphonic moiety is doubly ionized, offering no internal protons for protonation of die polymer backbone. 

The self-healing effect provided by dopant ions has been observed in the woric of Dominis etal (2003) for emeraldine salt primers loaded with different eorrosion inhibitors. Also, in the work of Kinlen et al (2002), PANi formulations with phosphonic acid derivatives as dopant anions showed better corrosion protection performances than formulations with sulfonic acids and derivatives. Kendig et al (2003) also reported the development of smart coatings based on conducting polymers doped with different corrosion inhibitors, showing that the release of inhibitors was triggered by the electrochemical activity at defects. In the work of Paliwoda-Porebska et al (2005, 2006) the cathodic delamination rate in iron coated with PPy doped with phosphomolybdates was fonnd to decrease in comparison with PPy doped with molybdates. 

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