Preparation, Characterization And Anti-corrosion Performance Of Aniline-pyrrole Copolymer Composite Materials

In recent years, the development and application of conductive polymer typeanti-corrosion composite materials has become a new hotspot in the area of the metalcorrosion and protection, which has provided a new solution to create a new stronganti-corrosion performance, green pollution-free, multifunctional and cheap and durableanti-corrosion materials.In this paper, we composed a series of conductive copolymer/inorganiccomposites, then the anti-corrosion coatings were prepared by filling them as conductive filler, andelaborating the phenomena and the principle of anti-corrosion coatings at the same time. The main workcontents are as followings:1. Firstly, this experiment adjusted different polymerization monomer ratio to preparepolyaniline/pyrrole conductive copolymer doped with SSA by chemical oxidativepolymerization in the condition of sulfosalicylic acid (SSA) system and ammoniumpersulfate (APS) as oxidizing agents. The molecular structure, microstructure and orderingdegree were analyzed by using FT-IR, SEM and XRD test means. The anti-corrosionproperties of PANI/PY-SSA for low alloy steel material were studied by using the Tafelpolarization curve method and EIS impedance spectrum afer filling the conductivecopolymer into EP resin at the same time. The results show that the anti-corrosion propertiesof PANI have been improved by PY copolymerizing, and that of PANI/PY-SSA is the bestwhen n (an):n (PY)=3:7, Ecorris-0.335V, Jcorris7.972A·cm-2, RCis2.103×105Ω·cm2,CCis1.646×10-8F·cm-2.2. This experiment took aniline and pyrrole monomer as polymerization raw materialsand APS as oxidant to prepare PANI/PY/TiO2composite by chemical oxidationpolymerization in the condition of nanometer TiO2as additive. It was analyzed andcharacterized by using FT-IR, SEM and XRD modern test means. The anti-corrosionproperties of PANI/PY/TiO2+EP coatings for low carbon steel material were studied byusing the Tafel polarization curve method, OCP temporal effectiveness and EIS impedancespectrum at the same time. The results show that the anti-corrosion ability is the strongestwhen the TiO2content account for30%of the tatal polymerization monomers. Thecomposites not only have the stronger metal passivation ability of PANI/PY, but also theTiO2particles enlarged the energy gaps of charge transfer and inhibit the charge transfereffectively in the process of electrochemical corrosion. PANI/PY/TiO2shows the betterabilities of metal protection than PANI and PANI/PY.3. The Conductive polymer/inorganic PANI/PY/TiO2composite films were deposited on the surface of stainless steel electrode by cyclic voltammetry method by taking aniline andpyrrole as electrochemical polymerization monomer. The electrochemical polymerizationprocess, microstructure and molecular structure are analyzed by the CV, SEM and FT-IR testmeans. Using the Tafel polarization curve and electrochemical impedance spectroscopy tostudy the anti-corrosion abilities of PANI/PY/TiO2film in the corrosion medium at the sametime. The results show that adding the TiO2improves the abilities of anode protection andinhibition the charge transform of conductive polymer film in the processes of corrosionreaction. The metal protection abilities of PANI/PY/TiO2composite film is significantlybetter than that of PANI and PANI/PY films. The anti-corrosion ability of compound film isthe best When TiO2content is1:60, proton acid concentration is1mol/L, scan frequency is10times, scanning rate is40mv/S, maximum scanning is1.2V, polymerization monomerproportion is AN: PY=2:1.4. Conductive copolymer/MMT composites were prepared by the method of intercalatingpolymerization in the condition of taking pyrrole monomer as copolymerization modifyingagent in order to improve the anti-corrosion properties of conductive copolymer. Themodern material test technologies such as FT-IR, XRD and SEM indicates that conductivecopolymer has been successfully inserted into the MMT layers and the stripped MMTpieces perfectly disperse in conductive copolymer, The maximum number of copolymerstripping MMT is9%; The anti-corrosion properties of epoxy resin coating contain thecomposite material as functional component for horseshoe iron was measured by electricitychemistry workstation in the3.5%NaCl solution which simulate sea water. Tafelpolarization curve and EIS electrochemical impedance spectroscopy confirms theanti-corrosion properties of the composite is best when the MMT content accounted for5%of monomer amount.