Abstract: Anatase TiO2 microspheres with uniform morphology and high crystallinity were facilely synthesized through a solvothermal method. The as-prepared samples were surface modified by stearic acid, and the as-prepared samples through surface modification could be readily dispersed in common non-polar solvents and mineral oils to obtain homogenous solutions, these homogenous solutions keeped unchanged for several months in ambient conditions. It could be reasonably inferred that the modified TiO2, because of a lot of long chains carboxylic acids on its surface, possessed a more effective improvement of the dispersity in liquid paraffin. The crystallographic structure, crystallite size, and surface morphology of as-prepared samples were analyzed through powder X-ray diffraction spectra (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), and thermogravimetry (TGA) respectively. In addition, the possible formation mechanism was discussed. The tribological properties of the as-prepared samples as an addictive of liquid paraffin were evaluated by a four-ball tester. The experimental results demonstrated that the as-prepared samples had excellent an anti-wear effect, friction-reduction property and could significantly improve the load-carrying capacity of liquid paraffin.

Key words: TiO2, surface modification, tribological property

摘要： 通过溶剂热法简便地合成了具有统一形貌和良好结晶度的锐钛矿型二氧化钛微球，并使用硬脂酸对所制备的产品进行表面改性，改性后的产品可以很容易的分散在非极性有机溶剂或者矿物油中形成均匀溶液，且上述溶液在室温环境下可较长时间保存而不出现沉淀。其原因是由于改性后产品表面存在长链羧酸基团，故而在油品中具有良好的分散性。通过 X 射线粉末衍射法 (XRD)，扫描电镜 (SEM)，红外测试 (FT-IR)，热重测试 (TGA) 等检测手段对其晶体结构、晶粒大小以及产品表面形貌进行表征，并且对产品的形成机理进行了探讨。通过四球摩擦试验机考察了修饰后产品作为液体石蜡为基础油润滑添加剂的摩擦学性能。结果表明，经过修饰后的产品拥有良好的抗摩减磨性能并且可以很好的提高液体石蜡载荷能力。

关键词: 二氧化钛, 表面修饰, 摩擦学性能