纳米TiO2有机表面改性的研究

利用硅烷偶联剂(KH-550)对表面包覆氧化硅的金红石相纳米TiO₂进行了有机表面改性。采用红外光谱(IR)、X射线光电子能谱(XPS)、热分析(TG-DTA)、BET、透射电镜(TEM)、润湿性和分散性实验等对表面改性前后的纳米TiO₂进行了表征。红外光谱和X射线光电子能谱表明，KH-550以化学键合的方式结合在纳米TiO₂的表面，并形成了有机包覆层。经测量，纳米TiO₂表面的KH-550的质量分数约为2.0%。讨论了产生KH-550理论包覆量与实际包覆量差异的原因。TEM、TG和BET得出的结果显示，在纳米TiO₂有机表面改性过程中存在明显的团聚现象，改进分散纳米TiO₂的方法是提高有机改性效果的关键。润湿性实验和分散性实验表明，经KH-550表面改性的纳米TiO₂同时具有亲水性和亲油性。

Study on Organic Surface Modification of Nanosized TiO2

The surface organic modification of nanosized TiO₂ pre-coated with silica in the rutile phase with silane coupling reagent KH-550, was studied. The prepared samples were characterized by FTIR, XPS, BET, TEM, TG and DTA techniques. According to the spectra of FTIR and XPS, it was inferred that the KH-550 was bound on the surface of nanosized TiO₂ particles and an organic coating layer also formed. The mass fraction of KH-550 on the surface of nanosized TiO₂ was measured to be about 2.0%. The influence factors which resulted in difference between experimental quantity and theoretical quantity of KH-550 bound on the surface of nanosized TiO₂ were discussed. Data from TEM, TG and BET indicated that there was an obvious agglomeration in the process of modification and that the improvement of dispersive methods of nanosized TiO₂ was the key to the improvement of the surface organic modification result. The wetting and dispersivity experiment showed that nanosized TiO₂ modified with KH-550 had both hydrophilicity and lipophilicity.