离子液体作为润滑脂添加剂的导电性和摩擦学性能

CONDUCTIVITY AND TRIBOLOGICAL PROPERTIES OF IONIC LIQUID AS GREASE ADDITIVES

用锂盐和聚环氧乙烷聚环氧丙烷单丁基醚(PAG)通过原位法制备新型离子液体,作为添加剂加入到PAO40基础油中,以聚四氟乙烯(PTFE)为稠化剂,制得电力复合脂。研究了传统离子液体和新型离子液体作为润滑脂添加剂的导电性和摩擦学性能。结果表明:离子液体的加入大幅度降低润滑脂的电阻率,提高润滑脂的电导率,减小接触电阻,具有优良的导电性;能够降低摩擦系数,减小磨痕宽度,体现了优良的减摩抗磨性能;在摩擦磨损过程中,离子液体中的阴离子能够在接触表面与金属发生化学反应,形成化学反应膜,从而起到减摩抗磨的作用;与传统离子液体相比,新型离子液体在摩擦学性能和导电性方面相差不大,而其制备工艺简单,具有更加广阔的应用前景。

New ionic liquids were prepared by the way of in-situ formation between lithium salts and polyether （PAG） and used as lubricating grease additives. The electricity compound grease was prepared by mixing PAO40 base oil with traditional or the new ionic liquid and a thickener polytetrafluoroethylene （PTFE）. The conductivity and tribological properties of traditional ionic liquid and new ionic liquids as additives were studied. It is observed that the addition of additives reduces significantly the volume re- sistivity and contact resistance of the electricity compound grease, but the conductivity and that the scar width and the friction coefficient are both reduced, reflecting the excellent antifriction and anti-wear per- formance of the greases adding the additives. The improvement of tribological properties should attrib- ute to the formation of the chemical reaction film due to the reactions of anion of the additives with metal surface. The results demonstrate that the new ionic liquids which are easily prepared can significantly improve the electrical conductivity and tribological properties of the grease.