粘度指数改进剂对车用润滑油性能影响

粘度指数改进剂的种类很多，性能各异，影响润滑油流变能力的粘度指数改进剂是调配车用油的关键成分。文章介绍了不同粘度指数改进剂的作用与性能，分析了不同粘度指数改进剂对车用油低温粘度及高温高剪切粘度产生的不同影响，阐述了不同粘度指数改进剂在不同油品中的选择性与适应性。对于不同用途的车用油，选择合适的粘度指数改进剂是非常重要的，除了考虑其增稠能力、低温性能等指标外，还需关注其剪切稳定性。实验证明，选择剪切稳定性好的粘度指数改进剂，对保证优良、稳定的产品质量，进而突出产品特色是不无裨益的。

EFFECTS OF VISCOSITY INDEX IMPROVERS ON THE PERFORMANCES OF VEHICLE LUBE OILS

There are many kinds of viscosity index improvers, and their performances are also respectively different. The viscosity index improver which affects the rheological ability of lubricating oil is the main ingredient for preparing the vehicle oil. In this paper, the functions and the performances of the different viscosity index improvers are introduced, and the effects of different viscosity index improvers on the low temperature viscosity and the high temperature high shear viscosity （HTHSV） of vehicle lubricating oil are analyzed. The selectivity and the adaptability of the different viscosity index improvers in different vehicle lubricating oils are elaborated also. Regarding to the vehicle oils with different uses, it is very important to choose appropriate viscosity index improver. Also, it is necessary to pay attention to the shear stability besides the thickening ability and low temperature performance. Experiments prove that the viscosity index improver with excellent shear stability can guarantee the stable product quality and the prominent product feature.