Structural investigation of lignosulfonate doped polyaniline

Lignosulfonate doped polyaniline (LGS-PANI) was prepared in the presence of sulfamic acid as a novel conducting filler. The room temperature conductivity of LGS-PANI increases more than two-fold with LGS at a mass fraction of 11.4 wt% and these conductivities (0.73-5.00 S/cm) exceed the highest reported for polymer acid-doped PANI systems. The conductivity stability and thermal stability are clearly improved at a certain content of LGS in LGS-PANI. These trends are accompanied by significant structural changes as evidenced by X-ray diffraction studies. The material characterization was also carried out by Fourier transform IR spectroscopy, thermogravimetric analysis and scanning electron microscopy. (C) 2009 Elsevier B.V. All rights reserved.