摘要
以不同极性基团的十八酸二乙醇胺、双β羟乙基十八胺及二辛基二硫代磷酸二乙醇胺为表面修饰剂,在醇-水体系中制备了3种纳米氟化镧粒子,通过透射电镜(TEM)及热重仪(TG)研究了纳米氟化镧粒子的形貌及表面修饰情况,采用离心沉降法考察了纳米粒子在基础油中的分散稳定性,用四球机考察了它们的摩擦学性能,最后采用扫描电子显微镜(SEM)和俄歇电子能谱仪(AES)分析了磨痕表面。结果表明:二烷基二硫代磷酸胺盐修饰的纳米粒子粒径更小,更均匀。表面修饰剂极性基团同无机纳米核强的化学作用且极性基团具有多长侧链更有利于纳米粒子在基础油中分散稳定。含牺牲性润滑元素硫和磷的表面修饰剂纳米粒子因极压膜的生成而有更好的极压抗磨性能。表面修饰剂的亲油链越长越有利于发挥纳米粒子的减摩作用。
Surface modifiers with different polar groups, such as, stearic acid diethanolamine, di （ β-ethoxyl ） stearamine and dioctyl dithiophosphoric acid diethanolamine ,were used to prepare three kinds of LaF3 nanoparticles in the mixture solvent of water-ethanol. Morphology and surface modification of LaF3 nanoparticles were investigated by TEM and TG, Dispersing stability of LaF3 nanoparticles in the base oil were measured by centrifugal settling. Tribological behaviors of LaF3 nanoparticles in the base oil were examined in a four-ball machine, and the wear scars of steel balls were investigated by SEM and AES. Results show that the size of LaF3 nanoparticles modified with dioctyl dithiophosphoric acid diethanolamine is smaller and more uniform;the dispersing stability of surface modified LaF3 nanoparticles in the base oil is better if the polar group of the modifier has a stronger acting force with inorganic core and more long side chains ; LaF3 nanoparticles have higher performances in extreme pressure and antifriction when surface modifiers contain sacrificial lubrication elements, such as, sulfur and phophorus, due to the production of extreme pressure membrane;the longer the lipophilic chain of the modifier is,the better its the friction reducing performance is.
出处
《润滑与密封》
CAS
CSCD
北大核心
2007年第7期9-12,15,共5页
Lubrication Engineering
基金
国家重大基础研究前期研究专项项目(2004CCA05400)
上海市科研计划项目(0352nm027).
