Study On Synthesis, Characterization And Properties Of Conductive Pedot Composite

Poly(3,4-ethylenedioxythiophene)(PEDOT) is one of the most successfully studied and widely used conductive polymers because of its high conductivity, excellent environmental stability, non-toxic advantage and high transparency in thin films. PEDOT has been investigated for many technological applications, such as antistatic coating, electroconductive film, supercapacitor, electroluminescent device, organic light emitting diode, organic solar cell, electromagnetic shielding material and inkjet printing. However, PEDOT can not be effectively processed by way of dissolving or melting, due to its rigid conjugated long chain structure which is similar to other eigenstates conductive polymers. Much research attention have been focused on mis meaningful research. Therefore, this research tries to explore new polymerization systems to improve the processing and applying properties of PEDOT. The main contents of this research are as follows:1. The water-dispersed conductive PEDOT composite materials are synthesized via chemical oxidative polymerization with lignosulfonate, a renewable resource, as a dopant and soft template in aqueous medium. The properties are characterized by FTIR, UV-Vis, TGA, SEM and the four probe conductivity measurement, respectively. The research results show that the PEDOT/LGS composite materials have advantages of excellent dispersion stability and good conductivity. The microscopic configuration are shown as tubular or fiber structure by scanning electron microscopy. The highest conductivity of the composite materials is about1.15×10-3S/cm by the four probe conductivity measurement.2. The synthesis conditions of poly(3,4-ethylenedioxythiophene) composite material doped with lignosulfonate are optimized with orthogonal test. The test results show that the conductivity have a certain impact by varying the dopant (lignosulfonate), oxidant((NH4)2S2O8), polymerization temperature and the solution pH. The optimal oxidative polymerization conditions have been found:the mass ratio of LGS/EDOT is2.0/1, the molar ratio of APS/EDOT is1.2/1, the. reaction temperature is0℃and the solution pH value is1.0. The highest conductivity of PEDOT/LGS composite materials synthesized under the optimal oxidative polymerization condition is1.71×10-2S/cm.3. The water-dispersed multi-walled carbon nanotube solutions are obtained by the self-assembly method with lignosulfonate, a polymer surfactant. Then, the excellent overall property PEDOT/MWNTs composite materials are synthesized via in situ chemical polymerization. The properties are characterized by SEM and four probe conductivity measurement, respectively. The research results show that the PEDOT/MWNTs composite materials have advantages of high conductivity and excellent dispersion stability. The conductivity of PEDOT/MWNTs composite materials have a certain impact by varying the dopant (MWNTs), oxidant((NH4S2O8), polymerization temperature and the solution pH. The optimal oxidative polymerization conditions have been found: the mass ratio of MWNTs/EDOT is2.0/1, the molar ratio of APS/EDOT is1.2/1, the reaction temperature is5℃and the solution pH value is0.8. The conductivity of PEDOT/MWNTs composite materials synthesized under the optimal oxidative polymerization condition is33.52S/cm.