改性硅胶作为PAO-10润滑添加剂摩擦学性能研究

Tribological behavior of modified silica gels as lubricant additives in PAO-10

目的合成4种改性硅胶,并将其作为PAO-10的润滑油添加剂,考察其摩擦学性能,并对润滑机理进行分析。方法采用棕榈酰氯对不同目数的普通硅胶进行改性,形成长烃链酰胺官能团,并通过傅里叶红外光谱仪对其结构进行确认。进一步通过摩擦磨损试验机和三维轮廓仪对润滑体系的摩擦学性能进行表征,采用接触角、扫描电子显微镜(SEM)、能谱仪(EDS)和X射线光电子能谱(XPS)对润滑机理进行研究。结果该系列改性硅胶添加剂极大改善了PAO-10的摩擦学性能。当向PAO-10中添加1.0%的改性硅胶S_(200~300)PMAD后,PAO-10的摩擦系数降低了60%,磨损体积降低了74%。结论摩擦副表面形成一定厚度的物理吸附膜层和含Fe_(2)O_(3)的化学反应膜层,二者共同提升了润滑体系的摩擦学性能,改性硅胶上附着的烷基链和活性杂原子是形成该保护膜的重要原因。

Purposes-To improve the tribological properties of PAO-10 by synthesizing 4 examples of silicone oil-based additives.Methods-Common silica gels with different meshes were modified by palmitoyl chloride with a simple method,by which the amide bond was formed.Then,the chemical structures were confirmed by FTIR and the tribological performances were evaluated by SRV and 3D profiler.Furthermore,a possible lubricant mechanism was proposed after the tests including contact angle,SEM,EDS and XPS.Results-The results indicated that these additives could greatly improve the tribological performance of base oils.Specifically,when 1.0%modified silicone S 200~300 PMAD was added to PAO-10,the friction coefficient of PAO-10 is reduced by 60%and the wear volume decreased by 74%.Conclusions-After the analysis including contact angle,SEM,EDS and XPS,it is shown that the alkyl chains and active heteroatoms on silica gels is crucial to its dispersion stability and the formation of protective films,which further improve the tribological performances of PAO-10.