纳米ZrO_(2) 改性水性环氧树脂的电化学性能研究

Electrochemical Performance of Waterborne Epoxy Coating Modified by Nano ZrO_(2)

为进一步提高涂覆水性环氧树脂的45钢在重防腐蚀领域的防腐蚀能力,研究纳米ZrO_(2)含量对水性环氧树脂复合涂层防腐蚀性能的影响规律,采用硅烷偶联剂KH550和钛酸酯偶联剂HY105分别改性纳米ZrO_(2),并将不同含量的2种改性纳米ZrO_(2)添加至环氧树脂制成复合涂料涂覆在45钢表面,通过极化曲线和电化学阻抗谱研究涂层的防腐蚀性能,用扫描电镜(SEM)观察涂层的表面形貌。结果表明:硅烷偶联剂和钛酸酯偶联剂改性后的纳米ZrO_(2)均可有效提高水性环氧涂层的防腐蚀性能,且最佳质量分数为1.0%,此时腐蚀电流分别达到0.2944μA/cm^(2)和0.0148μA/cm^(2)。此外,钛酸酯偶联剂改性后的复合涂层的防腐蚀性能在相同条件下优于硅烷偶联剂改性的复合涂层。与硅烷偶联剂改性后的复合涂层相比,钛酸酯偶联剂改性后的复合涂层孔分布更少、孔径更小。

For further improving the corrosion resistance of 45 steel coated with waterborne epoxy resin in the field of heavy corrosion,and studying the influence law of nano ZrO_(2)content on the corrosion resistance of waterborne epoxy composite coating,nano ZrO_(2)powders were modified by silane coupling agent KH550 and titanate coupling agent HY105,respectively.These two kinds of modified ZrO_(2)with different content were added into epoxy resin to make waterborne epoxy composite coatings on the surface of 45 steel.Furthermore,the corrosion resistance of coatings was studied by polarization curve and electrochemical impedance spectroscopy,and the surface morphology of the coating was observed by scanning electron microscope(SEM).Results showed that the nano ZrO_(2)modified by the silane coupling agent and the titanate coupling agent could effectively improve the corrosion resistance of the waterborne epoxy coating,and the optimal mass fraction was 1.0%(mass fraction).Meantime,the corrosion current reached 0.2944μA/cm^(2) and 0.0148μA/cm^(2),respectively.In addition,the corrosion resistance of the composite coating modified by titanate coupling agent was better than that of the composite coating modified by silane coupling agent under the same conditions.Compared with the composite coating modified by silane coupling agent,the composite coating modified by titanate coupling agent had the smallest pore distribution and the smallest pore size.