The Preparation Of Waterborne Alkyd Resin Is Studied

Low price soybean oil acid, tri-methylol propane, polyhydric acids (phthalic anhydride or trimellitic anhydride) were co-esterified in order to prepare aqueous alkyd resins. In the experiment, series factors affecting the performance of the resin were studied, including oil degrees, alcohol amount, ratio of trimellitic anhydride to polyacid, temperature, acid value, neutralizer dose, etc. The esterified neopentyl glycol based on their steric effect was used to improve the hydrolysis resistance of the resin. The results showed that when aqueous alkyd resin was prepared from soybean oil acid, the best oil degree was up to45%, alcohol amount was up to20%, suitable ratio of phthalic anhydride and trimellitic anhydride in polyacid partial was5:1, the first-step esterification temperature was220-240℃and the temperatures of the esterification after adding trimellitic anhydride was210-220℃. The resin acid value was ultimately controlled at50to60, and the dosage of neutralizing agent triethylamine was1.05times of theoretical calculation amount. In order to improve the hydrolysis resistance of the aqueous alkyd resin, the use of the steric effect of neopentyl glycol distinctively enhanced ester bond hydrolysis resistance performance, and the optimum dosage of the neopentyl glycol was15%of trimethylol propane. This could not only guarantee the water-soluble and film-forming performance of alkyd resin, and but also significantly improved the hydrolysis resistance of the alkyd resin.