油溶性纳米二氧化钛的制备及自修复性能研究

Preparation of oil soluble nano-TiO2 and its self-repairing performance

摘要:

摘要：纳米TiO2在润滑行业中应用的瓶颈问题是其在基础油中分散稳定性较差。研究以钛酸四丁酯（TBT）为引发剂，在60℃下引发δ-戊内酯（DVL）开环聚合生成四臂星型聚戊内酯（4-PVL），然后在酸性条件下水解得到油溶性纳米TiO2。SEM测试结果显示产物纳米TiO2具有大小均一的球形颗粒，其平均直径在20-30 nm左右。通过红外光谱（FT-IR）、X射线粉末衍射法（XRD）、热重分析（TG）等分析测试手段证明了纳米TiO2表面接枝了油溶性聚戊内酯（PVL），并能够在基础油中保持60天没有发生明显的沉淀现象，展现出良好的分散稳定性。由于球形纳米TiO2的“滚珠”效应和填充修复作用，复合纳米基础油的摩擦系数从0.049下降至0.025，平均磨斑直径从1028 μm 降低至979 μm，展现出良好的抗磨及自修复性能。

Abstract:

Abstract:The application of nano-TiO2 in the lubricating oil industry was seriously restricted because of its low dispersion stability. In this paper, tetrabutyl titanate (TBT) was used as the initiator to initiate the ring opening polymerization of δ-Valerolactone (DVL) at 60 ℃ to produce four arm star shaped polyvalerolactone (4-PVL), and then the oil soluble nano-TiO2 was hydrolyzed under acid condition. The Scanning electron microscopy (SEM) showed that the product nano-TiO2 had spherical particles of uniform size, with an average diameter of about 20-30 nm. This modification process was feasible, which was demonstrated by Fourier Transform Infrared Spectrometry (FT-IR), termogravimetric analysis (TG) and X-raw Diffraction (XRD). It had been proved that the dispersion stability of nano-TiO2 in base lubricating oil had been significantly optimized which could keep the stability of dispersion for 2 months without obvious precipitation. Lubricant with nano-TiO2 additive showed lower friction coefficient and wear spot diameter due to the “bearing effect” and “filling and repairing effect”. The friction coefficient of composite nano-base oil varied from 0.049 to 0.025, and the average wear spot diameter decreased from 1028 μm to 979 μm. Compounded nano-TiO2 lubricant exhibited excellent anti-wear and self-repairing performance.