METHOD FOR PREPARING DMPA MODIFIED WATERBORNE ALKYD RESIN

摘要

The present invention discloses a method for preparing a DMPA-modified waterborne alkyd resin, wherein the method comprises: a step for mixing 70-90 parts by weight of flaxseed oil at room temperature and 10-30 parts by weight of maleic acid anhydride, followed by heating up to 240-250C and maintaining the temperature for 7-9 hours to obtain a first product; a step for mixing 30-40 parts by weight of soybean oil, 10-20 parts by weight of poly-alcohol, and 0.005-0.01 parts by weight of potassium hydroxide, and heating up to a temperature of 240-250C and maintaining the temperature for 1-1.5 hours; a step for lowering the temperature of the reaction product obtained in the second step down to 170-190C, and adding thereto 20-30 parts by weight of phthalic acid anhydride, 8-15 parts by weight of DMPA, and 5-10 parts by weight of benzoic acid to reflux xylene, and heating up to a temperature of 170-190C and maintaining the temperature for 0.5-1.5 hours, and further heating up to a temperature of 200-210C and maintaining the temperature for 6-8 hours to obtain a second product; and a step for mixing the first product with 40-60 parts by weight of butyl ether, adding the second product thereto, and lowering the temperature down to 95-105C, and then adding an amine neutralizer to adjust the pH value of the mixture to 8.5-9 to obtain a waterborne phenol resin. The waterborne alkyd resin according to the present invention has greatly improved safety and environmental-friendliness.