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With increasing environmental regulations increasingly sophisticated and environmental, health, safety and energy-saving awareness, environment-friendly paint has become increasingly important. The research and development of water-based resins and waterborne coatings are becoming more in-depth and wide-ranging, became one of the coatings industry development trend. The domestic waterborne alkyd paint from the early 1960s, over the years, due to technical factors, the slow development so far. Domestic R \u0026 D waterborne alkyd system with similar foreign products have a larger gap, there is still a resin storage stability, chemical resistance, and poor water many problems, these problems directly affect waterborne alkyd resin widely used and comprehensive development. This thesis focuses on the status of waterborne alkyd paint Synthesis of epoxy-modified alkyd resin, prepared a storage stability, water resistance, fast drying epoxy modified aqueous alcohol acid resin, on this basis, and then optimize the performance of alkyd resin part, and then together with the pigments and fillers, additives, final waterborne alkyd varnish and primer, all aspects of performance has been improved to a large extent. Experiments using the alcoholysis synthetic alkyd resin. Studied the kind of raw materials and ratio, temperature, acid number, and alcohol excess impact on the properties of the resin product was characterized by infrared spectroscopy (IR), and determining the final process conditions and formulations. Choice of soya bean oil, tung oil, trimethylol propane, isophthalic acid, trimellitic anhydride as the main raw material for synthesis of the waterborne alkyd resin. The resin varnish configuration table dry 3h, the pragmatic 24h, water resistance for 24h, storage of four months, the hardness B. General performance, resulting in its value. Using epoxy resin-modified polyols, and then modified polyol alcoholysis vegetable oil, and then esterified to polycondensation, a carboxyl group, and the method of synthesis of epoxy-modified alkyd resin. Of the epoxy kind, ratio, feeding sequence and the experimental temperature, the catalyst the dry like factors impact on the properties of the resin; discussed the curing mechanism of the film, the hydrolytic stability of the resin; product by infrared spectroscopy (IR) the characterization; determine the final process conditions and formulation. The selection of soya bean oil, tung oil, an epoxy resin, trimethylol propane, isophthalic acid, trimellitic acid anhydride as the main raw material for synthesis of the modified alkyd resin. The degree of control oil is 48 to 50%, an alcohol excess of 1.2, a monoglyceride content of more than 40%, the final acid number of 42 to 48 mg KOH / g. Configuration of the modified waterborne alkyd primer dry table 2h, hard-working 16h, water resistance 32h unchanged, stored for 6 months does not precipitate, the pencil hardness of HB. To further enhance the water resistance, drying property, hardness and other properties of the resin, the water-soluble isocyanate, silica emulsion of a modified alkyd resin composite modified again. This modified waterborne alkyd primer table dry configure 1.5h, hard-working 14h, water resistance unchanged 36h, stored for eight months does not precipitate a pencil hardness of H. Through the comparison of before and after modification, the modified waterborne alkyd resin having excellent drying properties, water resistance and storage stability.
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