铝锆偶联剂的合成、表征及其对纳米TiO2的表面改性

以聚合氯化铝（PAC）、氧氯化锆和己二酸等为原料合成了带有羧基功能基的铝锆偶联剂， FTIR分析证明，己二酸分子中的一个羧基同时与铝和锆原子中心相连，另一羧基则作为偶联剂的功能基得以保留；TG-DTG分析表明，铝锆偶联剂分子中无机部分比重高达71%。利用合成的铝锆偶联剂对纳米TiO2进行表面改性，借助FTIR、TG-DTG、XRD、TEM和粒径分布等测试方法对纳米TiO2的界面性质进行分析。FTIR和TG-DTG分析证明，铝锆偶联剂在纳米TiO2表面形成化学吸附；粒径分布和Brookfield粘度测试说明，改性后纳米TiO2在水中的分散性显著提高。

Synthesis, Characterization and Application of Zircoaluminate Coupling Agent as a surface modifier of nanoTiO2

In this work, the synthesis, characterization and application of carboxyl zircoaluminate coupling agent as a surface modifier were investigated. The coupling agent was synthesized using polyaluminaum chloride, zirconium oxychloride, adipic acid, etc. FTIR indicated that one carboxy group of adipic acid formed a complex bridge between the aluminum and zirconium metal centers and the other carboxy group remained uncomplexed. The results of TG-DTG showed that the proportion of inorganic parts in the composition was as high as 71%. Then, surface modification of nanoTiO2 with zircoaluminate coupling agent was carried out. The interface property of prepared samples was characterized by FTIR, TG-DTG, XRD, TEM, particle size distribution and Brookfield viscosity. According to the spectra of FTIR and TG-DTG, it was inferred that chemical adsorption between surface modifier and the nanoTiO2 had happened during the modification reaction. The XRD tests confirmed that the modified nanoTiO2 samples kept the same bulk structure as the unmodified one. In addition, the results of particle size distribution and Brookfield viscosity showed that the dispersion of modified nanoTiO2 was improved significantly in water.