| Concrete structure is widely used. However, a variety of reasons result in a large number of reinforced concrete structure early fail in reinforced concrete structure, a lack of durability is one of the main reasons. Anticorrosive coating can form a protective barrier on the concrete surface and indirectly improve the durability of concrete. Due to its good corrosion resistance property, environmental friendly property and corrosion resistance property, waterborne epoxy resin coating materials get fast development. However, the preparation technology of waterborne epoxy resin is not perfect, and the proplems still remain in storage stability and usability during the preparation of water-based epoxy resin system.In this paper, based on the phase inversion emulsifieation mechanism of the epoxy resin, a key technology which is feasible and effective to prepare water-borne epoxy anticorrosive coating material is explored. By means of compounding emulsifiers, the influence of HLB, shear rate and preparation process on the properties of waterborne epoxy emulsion is researched.The results show that HLB of the emulsifier and stirring intensity have great influence on the stability of epoxy emulsion;When the HLB of the emulsifier which consist of Span60,OP-10 and SDBS is 10,emulsifying shearing rate is 2500 rpm,temperature is 60℃, a more stable epoxy resin emulsion system which has moderate viscosity and uniform particle size can be prepared.Based on the studies of two-component water-borne epoxy coatings studies,with the help of blending modification technology, a kind of waterborne epoxy resin coating material is modified employing castor oil,polymer powder and emulsified asphalt mrespectively under different dosage proportions,with the help of infrared spectrum,thermal weightlessness, fluorescence microscopy, scanning electron microscopy and dynamic mechanical analysis, the influence of modifying agent on coating curing reaction, compatibility, mechanical strength,corrosion resistance and the antipermeability, is tested. The results show that modified coating has good thermal stability, adhesion property and corrosion resistance property, which can resist penetration of water molecule and ion corrosion. After modification, the coating has better toughness and worse elongation and fracture strength, the dosage of the modifier have significant influence on the performance and the uneven dispersion of modifier is the main cause of weakening coating mechanical properties.The performance of the water-borne epoxy anticorrosive coating which is composed of the two-component epoxy resin emulsion and the surface modified titanium dioxide is studied. Results show that the dispersibility of inorganic particles in the emulsion is good, when filler content is over 15%, the bridging effect of the coupling agent can eliminate the interface investing, dense solid structure, weaken stress concentration and improve the mechanical properties. The corrosion resistance property of inorganic filler modified coating,especially the resistance to chloride is improved. |
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