The Preparation Of Water-Based Epoxy Heavy-duty Coating

A lot of infrastructures are constructed as the social is developing rapidly, meanwhile the use and maintenance of these buildings, such as railway, shipbuilding, automobile, bridges, pipelines are becoming important subject at present. Steel materials are widely used in most of buildings because of their easy installation, short construction cycle, light weight, good aseismatic performance, less pollution and other irreplaceable advantages. However, steel structure corrosion is a major issue. Faced with such urgent demand, heavy-duty coating emerges at the historic moment. Heavy-duty coating is a kind of special material which has a long-term anti-corrosion life in the severe corrosion engineering environment. Compared with the conventional anti-corrosive coatings, heavy-duty coatings have longer protecting life, which can be used 10 to 15 years even under the harsh environment, such as chemical industry and ocean.In this paper, we synthesized SiO2 hollow micro-spheres coating by template method. When the The concentration of sodium carboxymethyl cellulose is 2g/L, the CaCO3 sphere template own the best spherical morphology. We characterized the antirust paint using a transmission electron microscope (TEM) which illustrates the thickness of the shell is 0.5 mm, and the diameter of the hollow spheres is 1-2 mm. We modified FeOC1 antirust pigments with aniline via a hydrothermal method, and studied the influence of the dosage of modified FeOC1 material on the mechanical properties and anticorrosion performance of the coating. X-ray diffraction data collected for the samples illustrates that three main diffraction peaks appears in the pattern of FeOC1 and no peaks appears in the pattern of the modified FeOC1. The FTIR shows theexist of polyaniline and aniline oligomer in the modified FeOC1. Then we choose epoxy resin emulsion as film forming matter, first study the best formula of waterborne epoxy varnish coating are as follows:MU-601 epoxy resin emulsion (100 servings), waterborne epoxy resin curing agent CU-600 (20 servings), KH-550(3 servings), flash rust remover((2 servings). We obtained two kind of water-based epoxy heavy-duty coatings adding the SiO2 hollow spheres and modified FeOCl, respectively. When the amount of SiO2 hollow spheres is 6 servings and the amount of modified FeOCl is 8 servings, we can obtain the best coating. Potentiodynamic polarization curves showed that when we choose the amount of SiO2 hollow spheres is 6 servings and the aniline modified FeOCl dosage is 10 servings, the coating has the smallest corrosion current and its anticorrosive performance is superior to the epoxy resin varnish coating; After 1000 h neutral salt spray test, the coatings added the SiO2 hollow spheres and aniline modified FeOCl are in good condition and behaves excellent anti-corrosion performance.