Investigation of 4,4'-bis(2-[l-styryl]-l-benzenesulfonoic) diacid doped polyaniline

In this paper, 4,4'-bis(2-[l-styryl]-l-benzenesulfonoic) diacid (BSBD) doped polyaniline (PANI/BSBD) were prepared. The effects of doping temperature and dosage of BSBD on the conductivity and solubility of PANI/BSBD were mainly investigated. It was indicated that the conductivity increased with the increasing doping temperature and the BSBD dosage that both enhanced the doping level. However, dedoping of PANI/BSBD occurred at higher temperature, and caused a little decrease of the conductivity. The excessive BSBD appeared as an impurity to the final PANI/BSBD and decreased the conductivity. A favorable conductivity of 1.0 × 10^-2 S/cm can be achieved with the equal molar ratio of-N = to H⁺ under 90°C. UV-Vis spectra showed the absorption intensity at 630 nm decreased and an Einstein shift was observed with the increase of doping temperature and the BSBD dosage, which indicates the enhancement of PANI/BSBD doping level. It was indicated in FTIR spectra that both 1590 cm^-1 and 1499 cm^-1, which arose from the quinoid and benzenoid structures respectively, bathochromic shifted with the increase of BSBD dosage.