硫氮型苯硼酸酯的制备及摩擦学性能

Study on Preparation and Tribological Properties of S and N-containing Phenyl Borate Ester

摘要:

以二正辛胺和二硫化碳为原料合成含S、N的长链醇作为中间体，再与苯硼酸反应合成一种硫氮型苯硼酸酯润滑油添加剂，通过红外光谱分析对中间体和合成产物的结构进行了表征，并对合成产物进行了元素分析。对合成产物的水解稳定性和在全合成基础油聚α烯烃（PAO）中的油溶性进行分析。采用四球摩擦磨损试验机对其在PAO基础油中的极压性、抗磨性和减摩性能进行测试。采用扫描电镜（SEM）和能谱仪（EDS）对四球试验的钢球摩擦面进行分析。结果表明：水解时间超过180h，具有良好的水解稳定性；添加比例小于2.5%时，在PAO中完全溶解。添加量2.5%时，最大无卡咬负荷(PB)值1100N，比基础油增加了181％；磨斑直径(WSD)最小，达到0.48mm,比基础油下降30.4%；平均摩擦系数0.087，比基础油下降21.6%。说明硫氮型苯硼酸酯在PAO中表现出良好的极压性能、抗磨性能和一定的减摩性能。摩擦面磨损显著下降，摩擦面形成了含S、N、B的复合保护层。

Abstract:

A long chain alcohols with S and N was synthesized by di-n-octylamine and disulfide carbon as intermediate. Which reacted with benzene boric acid, a new type of nitrogen and sulfur containing phenylboronic lubricating oil additive was synthesized. The structure of the intermediate and the synthetic product was characterized by infrared spectroscopy. And elemental analysis was used to test the synthetic product. The hydrolysis stability and the oil solubility in the synthetic base oil (PAO) of the synthetic product were evaluated. The tribological performance of the synthetic product which was added in the PAO was test by four-ball friction and wear testing machine. Scanning electron microscopy (SEM) and energy spectrometer (EDS) was used to analysis the friction surface of steel balls. The results are as follows: the time of hydrolysis was more than 180 h. The synthetic product could completely dissolved in the PAO when the additive ratio was less than 2.5%. When the adding proportion was 2.5%, the PB was 1100 N, increased by 181%. The WSD reached the minimum (0.48mm), which was reduced 30.4%. And the average friction coefficient was reduced 21.6% to 0.087. The synthetic product showed good anti-extreme pressure, anti-wear performance and anti-friction performance. The results show that the wearing of the friction surface was decreased significantly when the synthetic product was added. The friction surface formed by a composite coating which containing S, N, B.