Melt solution processable conducting polyaniline: doping studies with a novel phosphoric acid ester

Polyaniline (PANI) was doped with a novel dopant, 3-pentadecylphenylphosphoric acid (PDPPA), having a long hydrophobic hydrocarbon side chain, either by mechanical mixing of emeraldine base and PDPPA or by the emulsion polymerization route using xylene or chloroform as the solvent. The resulting PANI-PDPPA complexes obtained were characterised by FTIR, UV-Vis, conductivity measurements, XRD, SEM, DSC, TGA and polarised light microscopy. The formation of the complex induces solubility of PANI in commonly used weakly polar or non-polar organic solvents such as xylene, THF, chloroform, etc. Protonation gives a plasticized PANI-PDPPA complex which can be processed by both thermal and solution techniques. On thermal processing, a free-standing flexible film with conductivities of the order 1.8 S cm(-1) was obtained. (C) 1999 Elsevier Science S.A. All rights reserved.