环境友好含氮润滑油添加剂的合成及其摩擦学性能

Synthesis and Tribological Properties of Environmental Friendly N-containing Lubricant Additives

设计合成了4种不同结构类型的新型环境友好润滑油添加剂(LA1~LA4),采用1 H NMR和MALDI-TOF-MS确证了其分子结构。考察了4种添加剂的油溶性、热稳定性和抗腐蚀性;在四球摩擦机上考察了其在液体石蜡(LP)中的摩擦学性能;用扫描电子显微镜(SEM)观察了钢球磨损的表面形貌,并用能谱分析仪(EDS)分析了钢球磨斑表面的元素组成,初步探讨了其摩擦作用机理。结果表明,4种添加剂具有优良的油溶性、热稳定性和抗腐蚀性,能够满足实际工况的要求;LP+1.0%LA2(质量分数,下同)的最大无卡咬负荷(PB)值比LP提高了87%,LP+1.0%LA3的烧结负荷(PD)值是LP的2倍,LP+1.0%LA3的钢球磨斑直径(WSD)只有LP的50%;SEM显示4种添加剂的加入能明显减小WSD,减少表面磨痕数量;EDS结果表明,添加剂在摩擦过程中形成复杂的反应膜。添加剂结构中的官能团会影响其性能,黄原酸酯基和羧酸酯基能够提高添加剂的极压抗磨性能。

Four environmental friendly lubricant additives,namely LA1,LA2,LA3 and LA4,were designed and synthesized,and the molecular structures were characterized by 1 H NMR and MALDI-TOF-MS.The oil solubility,thermal stability and corrosion resistance of these additives were studied.The tribological behaviors in liquid paraffin（LP）were evaluated with a four-ball machine.The surface morphology of the worn scars was observed by scanning electron microscopy（SEM）.The elemental composition of tribofilms was investigated by an energy dispersive spectroscopy（EDS）,and the action mechanism was preliminarily discussed.The results indicate that these additives possess good oil solubility,high thermal stability and excellent corrosion resistance,which could meet the requirements of practical working conditions.The maximum nonseizure load（PBvalue）of LP with 1.0% LA2 was 87% higher than that of LP.The sintered load（PDvalue）of LP with 1.0% LA3 was twice as large as LP.The wear scar diameter（WSD）of LP with 1.0% LA3 was only half of the value observed in LP.The SEM pictures show that the addition of four kinds of additives can significantly reduce the WSD and surface abrasion of LP.The EDS analyses reveal that a complicated reaction film was formed during the friction process.It found that the functional groups of the additives have a certain impact on its performance,for example,xanthate and carboxylate ester can improve the extreme pressure and anti-wear properties of additives.