聚磷酸铵对环氧涂层的阻燃性能和防腐蚀机理研究

Flame Retardancy and Anticorrosion Mechanism of Ammonium Polyphosphate in Epoxy Coatings

将环氧树脂(EP)、聚磷酸铵(APP)和固化剂共混制备环氧涂层,研究APP对环氧涂层的阻燃性能和耐腐蚀性能影响机理。结果表明:APP能够均匀分散在EP中,随着APP含量的增加,环氧涂层的耐腐蚀性能和阻燃性能均逐渐增强。当添加20%APP,环氧涂层呈现优良的耐腐蚀性能,涂层UL-94垂直燃烧等级达到V-0级,具有离火自熄的功能。当碳钢浸入APP的浸出液,碳钢表面可形成致密的磷化膜,磷化膜能够有效保护碳钢基体不受腐蚀,磷化膜对碳钢的保护效率达到87.1%。添加25%APP的EP经过400 h盐雾实验,涂层表面划痕处锈蚀轻微,也没有起泡现象,表明APP能够有效提高环氧涂层的耐腐蚀性能。

The epoxy coating was prepared by blending epoxy resin(EP), ammonium polyphosphate(APP) and curing agent, and the mechanism of APP on the flame retardancy and corrosion resistance of epoxy coating was studied. The results show that APP can be uniformly dispersed in EP. With the increasing of APP content, the corrosion resistance and flame retardancy of epoxy coating are gradually enhanced. When 20% APP is added, the epoxy coating exhibits excellent corrosion resistance, and the UL-94 vertical combustion level of the coating reaches V-0, which has the function of selfextinguishing from fire. When carbon steel is immersed in the leaching solution of APP, a dense phosphating film can be formed on the surface of carbon steel. The phosphating film can effectively protect the carbon steel substrate from corrosion, and the protection efficiency of the phosphating film on carbon steel reaches 87.1%. The EP added with 25%APP is subjected to a salt spray test for 400 h. The scratches on the coating surface are slightly rusted and there is no foaming, indicating that APP can effectively improve the corrosion resistance of epoxy coatings.