Preparation And Properties Of Polyaniline, Polypyrrole And Its Composites

In this papers chemical oxidation was used to synthesize conductive polymer power polyaniline and polypyrrole according orthogonal design ideas and optimized the synthesis process. The effects of temperature, hydrochloric acid concentration, the ratio of oxidant to aniline and metal ion doping on the conductivity of PAn were studied and the results showed that at low temperature can improve the conductivity of polyaniline, the conductivity of polyaniline increased with the oxidant at first and then decreased, Fe3 + doping had high conductivity, the conductivity of polyaniline increased significantly at a certain concentration of hydrochloric acid. Synthesis of polypyrrole obtained optimum conditions: oxidant ratio of 1:1, the proportion of dopant 3:4 and pH at 7. Polypyrrole as a functional component and epoxy resin as the membrane material by mechanical mixing to prepare uniform coating and then applied to the stainless steel surface. Studied electrochemical behavior of stainless steel with coating polypyrrole film and provided a theoretical basis for the further application of polypyrrole.PPy/MnO₂ organic - inorganic composite materials was prepared by situ composite method and its structure, crystal and morphology of the product were characterized. The results of characterization showed that MnO₂ composite material was coated by polypyrrole polymer chain and there was a certain interaction between the two, which reduced the agglomeration of nanoparticles to some extent. Compared PPy with PPy/MnO₂ with different amounts of MnO₂ composite product performance prepared under the same conditions and found that composites have better electrochemical activity.Chemical oxidation was used to synthesis PPy composites modified by PVA and successfully prepared PPy / PVA organic - organic composite materials with different PVA contents. The composite materials were characterized by FTIR, XRD, SEM and TG. Three-electrode system were used to test cyclic voltammetry of the composite materials and the results showed that the redox properties of composite materials and reversible relatively stable, reflecting the excellent electrochemical activity of composite materials. The redox and reversible properties of composite materials are more stable. The corrosion resistance was studied with composite materials as functional components coated on stainless steel. Impedance test results showed that the PPy / PVA composite film as functional components caused the impedance increasing two orders of magnitude compared to Single epoxy paint.