Synthesis of poly(o -phenylenediamine) nanofiber with novel structure and properties

The poly(o-phenylenediamine) (PoPD) was synthesized from the monomer o-phenylenediamine in various organic solvent medium viz. dimethyl sulfoxide (DMSO), N,N-dimethyl formamide (DMF) and methanol using ammonium per sulfate as a radical initiator. The structure just like polyaniline derivative with free NH functional groups of the synthesized polymers confirmed by various standard characterizations was explained from the proposed polymerization mechanism. All the synthesized polymers were completely soluble in common organic solvent like DMSO and DMF because of the presence of polar free NH functional groups in its structure. The formation of polymer nanofiber by reverse salting-out process was confirmed, and the synthesized polymer in DMSO medium was the best polymer in terms of nano-morphology as well as conducting properties. Interestingly, the average DC conductivity of undoped polymer film was recorded as 2.21 × 10−6 Scm−1 because of induced doping through self charge separation. Moreover, the conductivity of the polymer film was further increased to 1.16 × 10−3 Scm−1 after doping by sulfuric acid. Copyright © 2016 John Wiley & Sons, Ltd.