中文摘要：

在蓖麻油分子中引入硫，合成了一种新型环境友好润滑添加剂（SCO），并利用红外光谱对其主要官能团进行了表征。通过四球试验机考察了SCO在菜籽油中的抗磨性能与极压性能，用X射线光电子能谱仪对其磨痕表面元素进行分析，探讨该类添加剂的极压抗磨作用机理。结果表明，硫化蓖麻油润滑添加剂在菜籽油中具有优良的极压抗磨和减摩性能，其润滑作用机理是由于长链蓖麻油分子的载体作用、硫的高反应活性以及二者的协同作用与摩擦金属表面形成了一层高强度的吸附膜和（或）摩擦化学反应膜。

英文摘要：

A new type of environmental friendly lube additive,sulphurized castor oil（SCO） was prepared and its chemical structure was characterized by infrared spectrum. The tribological properties of SCO additive in rapeseed base oil were evaluated by four ball tester. The features and tribo-chemical species of the worn surfaces were analyzed by means of X-ray photoelectron spectroscope （XPS）. Results showed that SCO additive could effectively improved the load carrying capacity, extreme pressure anti-wear and friction-reducing abilities of rapeseed oil. The lubrication mechanism is inferred that a high strength adsorption film and a tribo-chemical reaction film formed on the rubbing surfaces due to the carrier effect of the long chain castor oil molecules, high reaction activity of sulfur and their synergisms.