Nanostructured poly(aniline-co-2,4-diaminophenol) synthesized via chemical copolymerization and the properties of the resulting copolymer

A conducting copolymer poly(aniline-co-2,4-diaminophenol) (PADAP) with two kinds of functional groups was first synthesized via the chemical copolymerization of aniline and 2,4-diaminophenol (DAP) in the acidic medium. The fast copolymerization rate resulted in the formation of PADAP copolymer nanostructures in the absence of templates. The spectra of FTIR and 1H NMR demonstrate that there is DAP unit in the polymer chain. The ΔHpp of the ESR signal and unpaired spin density of PADAP are very sensitive to the copolymer composition that is a function of monomer concentration ratio in the mixture. The properties of PADAP are affected by several polymerization factors, but the most important one among them is the monomer concentration ratio in the mixture used for the copolymerization. PADAP synthesized under the optimal copolymerization conditions has good redox activity from highly acidic solution to pH 12.0 in a wider potential range and has a conductivity very close to that of polyaniline. However, the pH dependence of the conductivity of PADAP is improved compared to that of polyaniline. The fast copolymerization rate and novel electrical properties of the copolymer are attributed to the synergistic effect of –NH2 and –OH functional groups in the copolymer chain.