掺杂纳米粒子有机-无机复合涂层的疏水、防护性能

Hydrophobic and Protective Performance of Organic-Inorganic Composite Coatings Doped by Nanoparticles

为了改善复合涂层的疏水、防护性能,在正硅酸乙酯/硅烷(偶联剂,KH550)杂化溶胶中掺杂了纳米SiO2,纳米TiO2和羟基化的多壁碳纳米管(MWCNTs-OH),采用浸渍-提拉法制备了3种有机-无机复合涂层,用不同的修饰剂对其表面进行修饰。通过水接触角、扫描电镜(SEM)和电化学方法,研究了不同修饰剂对涂层疏水和防护性能的影响。结果表明:十七氟癸基三甲氧基硅烷修饰剂对改善3种复合涂层的疏水性能效果最好,其接触角分别达到了120.95°,121.62°和146.58°;在3.5%NaCl溶液中3种复合涂层的腐蚀电流密度都比铝合金降低了3个数量级;3种复合涂层都具有良好的疏水和防护性能,其中MWCNTs-OH复合涂层的效果最佳。

To improve the hydrophobic and protective performance of composite coatings,nano-SiO2,nano-TiO2 and hydroxylated multi-walled carbon nano-tubes(MWCNTs-OH) were separately introduced into hybrid solution of ethyl orthosilicate and silane.Resultant hybrid solution was then adopted to prepare three kinds of organic-inorganic composite coatings by dipping and drawing method.As-obtained composite coatings were finally modified with different types of modifiers.The effects of different modifiers on the hydrophobic and protective performance of the composite coatings were investigated based on water contact angle measurement,scanning electron microscopic observation and electrochemical testing.Results indicate that 17-fluorine decyl trimethoxy silane as the modifier is the most effective in improving the hydrophobicity of the composite coatings,and contact angles of the three kinds of modified composite coatings are 120.95°,121.62° and 146.58°.The three kinds of as-prepared composite coatings all possessed good hydrophobic and protective performance,and the one doped with MWCNTs-OH possessed the best performance.In the meantime,the composite coatings all possessed excellent corrosion resistance in 3.5% NaCl solution,with the corrosion current density being lower than that of Al substrate by three orders of magnitude.