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A water - soluble alkyd resins based on polyhydric alcohols, polybasic acids and fatty acids as the main raw material, a polymer, a water - soluble alkyd resins obtained by the polycondensation reaction with water as a solvent containing a lower volatile organic compounds (VOC ) reduce harm to the environment and workers' health . Therefore , the theory and technology of water-soluble alkyd resin is important. In the the alkyd resins constant K , the oil degree OL and alcohol excess R for calculating the main parameters of the alkyd resin formulations , by contrast to the synthetic process using molten fatty acid method to the synthesis of alkyd resins, synthetic water-soluble alkyd resin use as the salt method . This article discusses the experimental raw materials , acid value , oil , alcohol excess and other factors affect the performance of water-soluble resin and the resin film , and ultimately determine the best conditions of synthetic water-soluble alkyd resin : water-soluble alkyd resin oil degrees oL = 40 % , the alcohol excess r = 0.20 , the final acid number of 40 to 50 mgKOH / g , the alkyd resin constant K = 1 ~~ 1.05 . The experimental material selection linseed oil fatty acids , trimethylolpropane , phthalic anhydride , trimellitic anhydride and maleic anhydride , ethylene glycol butyl ether as a co-solvent , the dimethylethanolamine for neutralizer . Through experimental analysis when the phthalic anhydride : trimellitic anhydride : Maleic anhydride = 1:0.125:0.167 (molar ratio) , the comprehensive performance of the water-soluble alkyd resin . Synthetic water-soluble alkyd resin in accordance with the above conditions , as a brown transparent liquid , and the solid content was 75.8 % , the viscosity of the 1700s , the water-soluble GT ; 100 times , the adhesion of the resin film is a hardness of 4H, flexibility and water also very good. Modified rosin and an amino resin to a water - soluble alkyd resin , rosin-modified water - soluble alkyd resin thermal decomposition temperature than unmodified improved experimental analyzes , when the rosin: fatty acid = 0.167 ( molar ratio ) , the lowest viscosity of the resin , the resin film leveling , gloss best; when the amino resin is added in an amount 20 to 25% of the alkyd resin , water-soluble alkyd resin gel time at 210 ℃ about 80s , soluble and better stability, the resin film adhesion 1 , hardness 4H, water resistance and flexibility is also good .
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