Synthesis Of Novel Pedot Composite And Application In Antistatic Coating

Poly(3,4-ethylenedioxythiophene)(PEDOT) is one of the most successful conducting polymers because of its excellent environmental stability, high conductivity and transparency in thin oxidized films. These unique optoelectronic properties make PEDOT for various applications such as in antistatic coatings, electroluminescent devices, solid electrolytic capacitor, through hole plating for printed wiring board, ITO substitution, electrochromic window, photovoltaic cells, organic light emitting diodes and sensors. However, all these attractive applications have been limited by the poor processability of pure PEDOT material, as it is generally known to be insoluble and infusible. Therefore, much research attention has been focused on the development of a processable PEDOT formulation. The thesis tries to improve the conductivity of PEDOT/PSS by optimizing polymerization process and improve processing performance by exploring new polymerization methods. Then, Antistatic coatings were prepared using the homemade PEDOT composite. The main contents of this thesis are as follows:(1)The poly(3,4-ethylenedioxythiophene)-poly(4-styrenesulfonate) has been prepared by oxidative polymerization of3,4-ethylenedioxythiophene in aqueous dispersion using poly(4-styrenesulfonate) as the charge-balancing dopant. The effect of each variable on the PEDOT:PSS composite properties is investigated. The test results show that the conductivity can be significantly enhanced by varying the monomer, dopant (poly(4-styrenesulfonate)), oxidant(K2S2O8and Iron(Ⅲ) sulfate), the solution pH, and polymerization temperature. The optimal oxidative polymerization conditions have been found:the reaction temperature is10℃, the pH value is1.5, the molar ratio of-SO3-/EDOT, KPS/EDOT and Fe3+/EDOT are1/1,1.2/1and0.00125/1. The conductivity of PEDOT/PSS prepared under the conditions is73S/cm.(2)PSS-PBA soft latex has been prepared by emulsion polymerization of BA using PSS as the emulsifier. PEDOT/PSS-PBA conductive dispersions were carried out using the PSS-PBA soft latex as the charge balancing dopant. The research results show that the conductivity of PEDOT:PSS-PBA decreased and the flexibility increased with increasing the PBA content as expected.(3)PEDOT/GS nanoparticles with enhanced conductivity and processability were prepared by oxidative polymerization in the presence of Gemini surfactant sodium lauryl diphenyl ether disulfonate. The effects of the concentration of GS, the pH value and types of oxidants on the resulting PEDOT/GS structure, morphology and electrical property were investigated. The electrical conductivity was varied with the polymerization conditions, and it was relatively high up to67S/cm. The morphology of the particles, determined by FE-SEM. appeared to be quite irregular and their sizes ranged from10to200nm in diameter. TG A result shows that prepared PEDOT is rather stable up to the temperature of220℃.(4)Antistatic coatings have been prepared using two homemade PEDOT composite as conductive component and applied to PET plastic substrates. The appearance, surface resistance, optical transmittance, washing resistance and adhesion performance of the coatings were investigated. The test results show that the sheen and the smoothness of coating film is high, the optical transmittance exceeds85%, the adhesion of coating achieves2, washing resistance and environmental stability are good, the surface resistance≤108Ω/sq, which meet the requirements of antistatic coating.