The Research On Synthesis Of Modified Air-drying Water-borne Alkyd Coating

With the limit of environment polity and rule and people's consciousness for environment protection in recent years, more attentions have focused in the environment friendly coating. The research and application of water-borne coating become one of the main fashion in coating industry.In this paper, in order to improve synthetic properties of water-borne coatings, we detailed studied the synthetic techniques and factors of air-drying and styrene, acrylic acid/ester modified water-borne alkyd resin.Fatty-acid solvent method was adopted to synthesize the alkyd resin. The affects of synthetic material and variable resin have been studied, such as variance resin, type of row materials, type of additives and proportion of each material , the best synthetic way and formula of water-borne alkyd resin were found: The suitable oil length was in the range of 45-50%, the excess of alcohol was 1.07, the final acid value was 40-50mgKOH/g. Used talloleic acid,colophony,isophthalic acid,trimethylol propane ,neopentyl glycol and trimellitic anhydride as row materials, synthesized the productive resin by the fatty-acid solvent method. Ammonia and thiethylamine were used as neutralizing agent, butyl cellosolve as cosolvent. The properties of the water-borne primer coating that was prepared with the water-borne resin, such as the hardness, adhesion, impact-resistance and solvent-resistance, were up to criterion of water-borne industrial primer.The styrene/ acrylic acid /ester were used as modifier, through the copolymerization to synthesize modified alkyd resin. In the experiment, through the researches of variable of resin , dosage of modifiers, temperature of copolymerization and manner of adding materials, we found the suitable modified approach of water-borne alkyd resin: talloleic acid,isophthalic acid,trimethylol propane ,pentaerythrite,benzoic acid, maleic anhydride as row materials, synthesized the basic alkyd resin by the fatty-acid solvent method; the styrene, acrylic acid, methyl methacrylate as modifier. The modification was : the suitable range of oil length is 50-55%,and excess of alcohol is 1.17 , under the temperature between 125-130℃,then adding the mixture modifiers into the basic resin drop by drop, of which proportion range was 40-50%, 4.5-5h was needed to complete this modification process.The properties of the water-borne acquer enamel that was prepared with the...