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Acrylate - two-component polyurethane system polymer hydroxyl acrylate and polyisocyanate has good heat resistance, corrosion resistance, adhesion characteristics, have been widely used in anti-corrosion coatings, and the hydroxyl acrylate emulsion hydrophilic polyisocyanate used in anti-corrosion coatings, the corrosion resistance of the coating can be compared with the solvent-based is still a certain gap. In order to further improve its corrosion resistance, this paper were synthesized phosphate containing hydroxy acrylate emulsion, and water-dispersible polyisocyanate resin prepared by non-ionic modification technology. Discussed the test process of the emulsion and the curing agent on the reaction process, studied of emulsifiers, phosphate ester monomers, hydroxyl content, as well as self-crosslinking monomers on the properties of emulsion, water-dispersible polyisocyanate preparation of esters ring polyether of propylene oxide with ethylene oxide, the molecular weight of the polyether, polyiso cyanate ester group with the molar ratio of the hydroxyl group, multiple types of the isocyanate impact on the dispersion properties of the product in coatings application performance. The experiments show that the emulsion polymerization, the monomer is added in the core-shell two-part, the use of the copolymer \Jia an amount of SDS was 0.6% SE-1ON 0.9%; crosslinking monomer added in an amount of 2% of the total monomer; hydroxyl content of 2%, the water resistance, mechanical properties of the film-forming material to achieve the most Jia; the phosphate monomer added calcium ion stability of the emulsion, the anti-flash erosion ability, and wet adhesion of the coating has been significantly improved, when added up to 4%, the coating without flash erosion phenomenon. Water-dispersible polyisocyanate ester production, the reaction temperature at 80 - ℃, the viscosity of the resulting product is moderate, multi-iso-cyanate ester group content substantially with the theoretical design match; 3 times feeding the hydrophilic polyethers, the reaction more smoothly; optional aliphatic isocyanate for the preparation of the hydrophilic polyisocyanate, the reaction rate is moderate, in the preparation of the anti-corrosion coatings, anti-corrosion coating film, mechanical properties are superior to aromatic polyisocyanate; ethylene oxide polyether relative The molecular mass of 400 to 600, the relative molecular mass of the propylene oxide polyether 1000, both the equivalent ratio of 6:4, grafted with the polyisocyanate, the low viscosity of the resulting product is well-dispersed in the paint; comprehensive consideration of the hydrophilic sexual polyisocyanate in Coatings dispersibility and anti-corrosion of the formulated coatings -NCO/-OH equivalent ratio of 6.0 is more appropriate.
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