Conductive Polyaniline And Its Application In Electrolytic Capacitor

Conducting dodecylbenzenesulphonic acid (DBSA) doped-polyaniline solutions have been synthesised via inverse emulsion and direct microemulsion. The experiments have been designed according to the Uniform Design method and the best conditions of the chemical reaction have been summarized in this work. Moreover, the study on secondary doping method has been carried on the prepared polyaniline. Polyanilines synthesised by two methods were characterized by FT-IR, UV-Vis, TG, XRD and TEM. The polyaniline solution better in properties has been prepared in the fabrication of capacitor. A new type of polyaniliane mixed capacitor has been developed. The manufacturing technology and characteristics of this new type capacitor have been studied. Furthermore, the Current-Voltage characteristics of Al/Al₂O₃/PAn system and Al/Al₂O₃/liquid electrolyte system have also been studied, and the application of conducting polyaniline to capacitor was presented.Compared with the direct microemulsion, the DBSA doped-polyaniline synthesised via inverse emulsion was better in yield and conductivity, smaller in size. But the conducting polyaniline solution synthesised in this way was not fit for the preparation of capatitor. The secondary doping method could markedly enhance the conductivity of the doped-polyaniline. The polyaniline mixed capacitor with excellent characteristics could be prepared by carbonization before dipping the polyaniline/CHCl₃ solution. Compared with the conventional aluminium electrolytic capacitor, the polyaniline mixed capacitor possessed not only low impedance-high freqency characteristics, but also excellent temperature characteristics. Under working conditions, this capacitor can keep high reliability. In addition, the Al/Al₂O₃/PAn system did not show the characteristics called unilateral conduction as obviously as the Al/Al₂O₃/liquid electrolyte system.