Cation-Polyaniline/Montmorillonite Anticorrosive Coating Preparation And Performance Study

In this paper, combined with the methods of single factor and orthogonal test, the modified montmorillonite with aniline(An-MMT), the modified montmorillonite with poly aniline (PAn/MMT) and PAn/MMT doping silver ion(Ag--PAn/MMT) were prepared in situ intercalating, in situ polymerization and adsorpting cationic, respectively. The composite coating was also prepared by using of the packing of Ag--PAn/MMT and the matrix of epoxy resin; Moreover, the preparing process, structure and property of Ag+-PAn/MMT and the composite coating, and the interrelation between them were investigated.The properties of An-MMT, PAn/MMT and Ag+-PAn/MMT were analysed by means of XRD, BET, ICP and FT-IR, respectively. The results showed that the optimal technological conditions of preparing An-MMT were as follows intercalating time was3h, the dosage of CTAB of MMT was30%, the intercalating temperature was80℃and the dosage of An of MMT was20%; the interlayer spacing d001could reach to38.4A and the specific surface area9.88m2/g. The optimal technological conditions of preparing PAn/MMT were as follows the temperature was0℃, reaction time was6h, the ratio of initiator was30%, pH was2; doping in ammonia water for3h, the electrical conductivity of Ag+-PAn/MMT could be0.032S.cm-1. The antibacterial experiment test of PAn/MMT and Ag+-PAn/MMT showed that the antibacterial rate could be90%in24h and the slow-release performance of Ag+in Ag+-PAn/MMT was0.11ppm after20d.The results also showed that when the content of Ag+-PAn/MMT was20%, the surface resistance and corrosion potentia of Tafel curve were107Ω and70mv and the corrosion current decreased from10-5.4A/cm2to10-6.7A/cm2.Composite coating accelerates soaking in5%NaCl solution experiment results had reached the185d, neutral salt spray test results reached18d, in1mol/L NaOH and H2SO4soak for30d without change. The Ag+-PAn/MMT composite coating had antibacterial effect and the coating bacteriostasis rate was95.8%with the adding amount of20%.The studies revealed that when the packing content was less than20%, the adhesion level, thickness level, toughness level, impact strength, hardness of composite coating were less than1, less than58μm,12,53k·cm and89A, respectively.