Chromium-free water-based coating, and preparation method and application thereof

The invention discloses a chromium-free water-based coating. The coating is composed of 20%-30% of A, 5%-15% of B, 5%-10% of Al powder, 25%-50% of Zn powder, 10%-30% of water-based resin or emulsion and 5%-20% of water, wherein the A is obtained through a reaction of methyl phthalic acid, ZrCl4 and 3-aminopropionic acid, and the B is obtained by reaction of a silane coupling agent and sorbic acid.A preparation method of the coating comprises the steps: uniformly mixing the A and the B; and then adding other components, fully stirring, and uniformly mixing. According to the water-based coating, the use of chromium is avoided, and the water-based coating is environment-friendly; the corrosion resistance is strong, the stability is good, the long-time storage can be realized, and no precipitate is generated in the quality guarantee period. 本发明公开了一种无铬水性涂料。该涂料由20％-30％的A、5％-15％的B、5％-10％的Al粉、25％-50％的Zn粉、10％-30％的水性树脂或乳液、5％-20％的水组成。其中，A由甲基邻苯二甲酸、ZrCl4以及3-氨基丙酸反应得到；B由硅烷偶联剂和山梨酸反应得到。该涂料的制备方法：先将A和B混合均匀；然后向其中加入其它组分，充分搅拌，混合均匀