研究了含量分别为0%,1%,3%和5%(质量分数)的硅烷偶联剂改性前后的纳米TiO_2对涂覆在45#碳钢上的聚氨酯涂层耐蚀性能的影响。场发射电镜(FESEM)测试结果表明,未改性纳米TiO_2在涂层中以团聚体的状态存在,经过硅烷偶联剂KH-570改性后的纳米TiO_2在涂层中均匀分散,其中含量为3%的涂层结构最为致密。采用电化学阻抗(EIS)技术研究了纳米TiO_2/聚氨酯复合涂层在3.5%Na Cl溶液中浸泡不同时间的阻抗行为,实验结果表明添加硅烷偶联剂改性纳米TiO_2可明显提高聚氨酯涂层的耐蚀性,其中含3%改性纳米TiO_2的涂层在浸泡过程中,始终呈现一个时间常数特征,在浸泡至2880 h后,涂层电阻仍然为2.6×108Ω·cm2,明显高于其他组分的涂层电阻,表明该涂层具有最好的耐蚀性。 The effects of nano-TiO 2 modified by silane coupling agent (0%, 1%, 3% and 5%, respectively) on the corrosion resistance of polyurethane coatings on 45 # carbon steel were studied. Field emission electron microscopy (FESEM) test results show that the unmodified nano-TiO 2 exists in the coating state as aggregates, and the nano-TiO 2 modified by the silane coupling agent KH-570 is uniformly dispersed in the coating, wherein the content is 3% of the most compact structure of the coating. The electrochemical impedance spectroscopy (EIS) was used to study the impedance behavior of nano-TiO 2 / polyurethane composite coating immersed in 3.5% NaCl solution for different time. The experimental results show that the addition of silane coupling agent modified nano-TiO 2 can significantly improve the polyurethane coating Corrosion resistance. The coating containing 3% modified nano-TiO 2 always shows a time-constant characteristic during immersion. After soaking for 2880 h, the coating resistance is still 2.6 × 10 8 Ω · cm 2, which is obviously higher than other groups The coating resistance, indicating that the coating has the best corrosion resistance.