本发明涉及金属腐蚀与防护领域，特别涉及一种聚多巴胺改性三聚磷酸铝缓蚀剂及其制备方法和应用，其中，一种聚多巴胺改性三聚磷酸铝缓蚀剂的制备方法，包括如下制备步骤：步骤一、将多巴胺和三羟甲基氨基甲烷加入含有三聚磷酸铝的预分散液中进行聚合反应；步骤二、待步骤一的反应体系溶液呈黑色或深褐色后，将反应体系的溶液离心后得到的沉淀，经过干燥即得所述缓蚀剂；其中，所述三聚磷酸铝与多巴胺的摩尔比为(3 .5～18)：(19～53)。本发明提供的一种聚多巴胺改性三聚磷酸铝缓蚀剂的制备方法，聚多巴胺包覆在三聚磷酸铝填料颗粒的表面并通过聚多巴胺附着在金属基材上；从而进一步起到缓蚀效果，使得防腐效果更为持久。

The present invention relates to the field of metal corrosion and protection, in particular to a polydopamine modified aluminum tripolyphosphate corrosion inhibitor and its preparation method and application. The preparation method of a polydopamine modified aluminum tripolyphosphate corrosion inhibitor includes the following preparation steps: step 1, adding dobutamine and trimethylaminomethane to a pre dispersed solution containing aluminum tripolyphosphate for polymerization reaction; Step 2: After the reaction system solution in Step 1 turns black or dark brown, the precipitate obtained by centrifuging the reaction system solution is dried to obtain the corrosion inhibitor; Among them, the molar ratio of aluminum tripolyphosphate to dopamine is (3.5-18): (19-53). The present invention provides a preparation method for a polydopamine modified aluminum tripolyphosphate corrosion inhibitor, wherein polydopamine is coated on the surface of aluminum tripolyphosphate filler particles and attached to a metal substrate through polydopamine; Thus further achieving a corrosion inhibition effect, making the anti-corrosion effect more durable.