油酸修饰CuS纳米颗粒的原位合成及其摩擦学性能

利用原位合成法室温下直接在基础油中成功制备了油酸修饰CuS 纳米颗粒, 将其长时间静置, 不会发生纳米颗粒的团聚. TEM 研究表明, 该方法制备的纳米颗粒粒径大约为30 nm. 红外光谱结果表明, 由于油酸的羧基与无机CuS纳米颗粒表面发生了化学吸附,使无机纳米颗粒的表面有一层有机修饰层, 从而增强了其油溶性.摩擦磨损试验结果表明,该添加剂在基础油中能起到抗磨减摩的效果.随着添加剂浓度的增大, 摩擦系数和磨斑直径都呈现下降趋势,当添加剂浓度为0.1%(w)时, 摩擦系数和磨斑直径都达到最小值,但是进一步增加添加剂浓度, 摩擦系数与磨斑直径又都开始增大. SEM 研究结果表明, 油酸修饰CuS 纳米颗粒能起到抗磨减摩作用的原因是因为其有利于在摩擦副表面形成牢固的润滑膜.

In-situ Synthesis and Tribology Property of Oleic Acid-modified CuS Nanoparticles

Oleic acid-modified CuS nanoparticles, which can be placed in a long stretch of time without any occurrence of nanoparticle aggregation, were successfully synthesized in-situ in base oil at room temperature. TEM study showed that the average size of the surface-modified nanoparticles prepared by this method was about 30 nm. IR study indicated that the surface of inorganic CuS nanoparticles reacted with carboxyl group of oleic acid via chemical adsorption, which resulted in a layer of organic modification on the surface of CuS nanoparticles and greatly improved their oil-soluble ability. Friction and wear study demonstrated that this kind of lubricant additives could greatly improve the property of antiwear and friction reduction of the base oil. As the increase of additive concentration, both the friction coefficient and wear scar diameter began to dramatically decrease. When the additive concentration was 0.1%(w), both of them reached the lowest points. However, with the further increase of additive concentration both of them began to increase. SEM study proved that the reason was that the oleic acid-modified CuS nanoparticles could help to form firm lubricating membrane between the surfaces of the friction pairs.