Synthesis of conductive poly (3-aminobenzoic acid) nanostructures with different shapes in acidic ionic liquids medium

Abstract

A series of acidic ionic liquid (ILs) based on imidazole and pyridine were synthesized and fully characterized by using FTIR, 1H and 13C NMR techniques. The acidic ILs applied as solvent and dopant for polymerization of 3-aminobenzoic acid (3ABA) by using of ammonium persulfate as an initiator. The synthesized P3ABAs-acidic ILs were characterized by FTIR, XRD, SEM, UV-Visible and TG-DTG analysis. The electrical conductivity of P3ABAs samples was measured by four probe method. The P3ABA-[PyCAA][HSO4] (0.30 S/cm) exhibited a higher electrical conductivity than that of the P3ABA-[HPy]HSO4] (0.28 S/cm), P3ABA-[IMBS][Cl] (0.22 S/cm) and bare P3ABA (0.20 S/cm). Based on the SEM micrographs, the acidic ILs changed the morphology of the P3ABA from being completely granular. The XRD patterns of the P3ABAs-acidic ILs samples displayed a more crystalline nature than that of bare P3ABA. The solubility and viscosity of P3ABAs-acidic ILs in polar organic solvents were greater than in bare P3ABA. Moreover, absorption (UV-vis) properties of the synthesized P3ABAs in the presence and absence of acidic ILs were examined. Based on TG-DTG curves, the thermal stability of the P3ABAs-acidic ILs was improved relative to bare P3ABA. The results showed that acidic ILs species form soft templates which assembled 3ABA molecules into specific nanostructures.