油溶性离子液体作为润滑油添加剂的摩擦学性能研究

为解决离子液体在基础油中溶解性差、不宜用作润滑添加剂的问题,通过分子设计制备了极性较小的十六烷基三辛基季膦磷酸二异辛酯盐和十六烷基三辛基季胺多库酯钠盐2种油溶性离子液体,其在碳氢润滑油聚ɑ烯烃(PAO10)中均具有较好的溶解性。采用铜片腐蚀试验考察了2种离子液体的腐蚀性;通过Optimol SRV-IV往复振动摩擦磨损试验机测试了2种离子液体作为PAO10基础油添加剂的摩擦学性能,通过多功能X射线光电子能谱仪(XPS)和原位接触电阻(ECR)表征推导了离子液体添加剂在PAO基础油中的润滑机理。结果表明:2种离子液体作为PAO10的添加剂无腐蚀,完全符合对润滑添加剂的要求。2种离子液体添加剂比空白基础油和传统工业添加剂ZDDP均具有更好的减摩抗磨性能。2种离子液体添加剂会在摩擦副表面形成有效的吸附膜和发生复杂的摩擦化学反应,因而使离子液体具有优异的减摩抗磨性能。

Tribological Performance of Oil-Soluble Ionic Liquids as Additives in Lubricant Oil

Two types of oil-soluble ionic liquids (ILs) hexadecyltrioctyl phosphonium bis (2-ethylhexyl) phosphate and hexadecyltrioctyl ammonium bis(2-ethylhexyl) sulfosuccinate were prepared by molecular design,which had good solubility in polyalphaolefin (PAO10).Copper strip corrosion test was used to assess the corrosion resistance,and oscillating tribometer was used to evaluate the tribological properties.X-ray photoelectron spectroscopy (XPS) and in-situ electrical contact resistance measurement (ECR) were used to deduce the lubrication mechanism of ILs additives in PAO10.Results showed that two kinds of ILs fully met the requirements of lubricant additives without any corrosion.Besides,these ILs additives had better friction reduction and wear resistance performances than those of the blank base oil and the traditional industrial additive zinc dialkyldithiophosphate (ZDDP).The ILs additives formed the effective adsorption films on the friction pair and the complicated tribochemical reactions occurred,resulting into the excellent friction reduction and wear resistance.