改性石墨烯/聚苯胺的制备及其环氧涂层的防腐蚀性能

为了改善环氧树脂防腐蚀涂料存在的孔洞缺陷,以改性石墨烯/聚苯胺复合材料作填料来提高环氧涂料的防腐蚀性能。首先采用改进的Hummers法制备了氧化石墨烯(GO),再利用对苯二胺还原GO得到改性石墨烯(PGO),进一步制备出改性石墨烯/聚苯胺(PGO/PANI)复合材料。通过拉曼光谱仪、场发射扫描电镜等研究了PGO/PANI的结构和微观形貌,利用盐雾试验、Tafel曲线和电化学阻抗谱研究了 PGO/PANI的防腐蚀性能。结果表明:PGO/PANI涂层的腐蚀等级由空白环氧涂层的10级提高到5级;PGO与PANI有良好的协同作用,PGO与苯胺单体质量比为0.10时,所制备的PGO/PANI复合涂层的防腐蚀效果较好,腐蚀电压为-194.59mV (vs SCE)、腐蚀电流密度为2.12×10^-9A/cm^2.

Preparation of Modified Graphene Oxide/Polyaniline Composites and Its Application in Anticorrosion Epoxy Coating

Graphene and polyaniline were used as fillers to improve the hole defect and enhance anti-corrosive performance of epoxy coating. In this study, the graphene oxide (GO) was prepared by the modified Hummers method, and the modified graphene PGO was obtained by the functionalization of GO with p-phenylenediamine, and then the modified graphene/polyaniline composites (PGO/PANI ) were prepared. The structure and morphology of PGO/PANI were characterized by Raman spectrometer and FE-SEM. The anti-corrosion performance of PGO/PANI was investigated by the salt spray tester, Tafel curves and electrochemical impedance spectroscopy (EIS). Results showed that the corrosion grade of PGO/PANI coating was increased to Grade 5 from Grade 10 of blank epoxy coatings, and PGO and PANI had good synergistic effect. Moreover, the PGO/PANI coating with 10% of PGO had the highest corrosion potential of-194.59 mV(vs SCE) and the lowest corrosion current density of 2.12×10^-9A/cm^2.