A Novel Enhancement of Nano Structure by Organic Acid Dopants in Emulsion Polymerization of Poly(o-toluidine)

A simple, more facile and green approach for the synthesis of poly(o-toluidine) (POT) has been described, by using oxidative emulsion polymn. in a heterogeneous phase by using ammonium persulfate as an oxidant and org. acids as dopant, acids used such as tartaric, oxalic and citric. The effect or influence of these dopants on cond., morphol. of the nano structure of POT and phys. properties are well studied and found that it depends on the nature and type of the functional org. acid dopants. By using this synthetic approach we have obtained POT nanostructures of uniform granular morphol., with av. 40-100 nm particle size doped with oxalic or citric acid, whereas in tartaric acid doped POT fibrilar morphol. with 40-60 nm size nano fibers was ascertained. These compds. were characterized by UV-Visible, FT-IR, SEM, and XRD. Elec. cond. studies of these materials were also carried out and found increase in cond. with citric acid and oxalic acid doped POT as compared to the tartaric acid. XRD studies showed partial cryst. nature of tartaric acid doped POT polymer as compared to others. By using this emulsion process, POT nanostructure formed with 60-100 nm diam. size having high yield, cond., and improved soly. in org. solvents in the emeraldine salt phase of polymer (confirmed by the presence of characteristic peaks at 420 nm and ~800-850 nm). The influences of reaction conditions, e.g. monomer, acid concn. on the physico-chem. properties were also investigated.