ZDDP热稳定性及其对抗磨性能的影响

使用热重法（TGA）和红外法（FTIR）研究了不同ZDDP的热稳定性能,Prim.ZDDP热稳定性能最好,其后依次为Sec.ZDDP-4,Sec.ZDDP-3,Mixed ZDDP,Sec.ZDDP-2,Sec.ZDDP-1。不同添加剂对ZDDP分解也有一定影响,其中清净剂能延缓ZDDP的分解;抗氧剂在短时间内表现不明显,氧化8 h则也能在一定程度上延缓ZDDP的分解;分散剂与抗氧剂效果相似,且同时能把分解的物质分散于油品中,在整个氧化过程中保持油品透明无沉淀。在单剂抗磨性能方面,表现最好的为Prim.ZDDP,Mixed ZDDP与Prim.ZDDP相差不大,其次为Sec.ZDDP-3,Sec.ZDDP-1/Sec.ZDDP-2,Sec.ZDDP-4。油品氧化后,其抗磨性能出现一个先升后降的过程,不同的ZDDP分解速率不一样,导致其在氧化不同时间后抗磨性能出现分化,表现最好的为Prim.ZDDP。

Thermal Stability of Zinc Dialkyldithiophosphates and Its Influence on Antiwear Performance

Thermogravimetric Analysis （TGA） and Fourier Transform Infrared Spectroscopy（FTIR） were used to study the thermal stability of kinds of ZDDPs. The result showed that Prim. ZDDP has the best thermal stability,and then is Sec. ZD- DP-4,Sec. ZDDP- 3, Mixed ZDDP, Sec. ZDDP- 2 and Sec. ZDDP- 1. Various additives show different effects on the thermal stability of the ZDDP. The detergent can slow down the ZDDP decomposition, while the antioxidant just shows a minor effect on the ZDDP decomposition in a short term. However it also can certainly decrease the ZDDP decomposition rate after oxidation for 8 hours. Therefore, the dispersant has a similar effect on the thermal stability of the ZDDP with an- tioxidant. Furthermore, it can disperse the thermal degradation products and keep the oil transparence. Prim. ZDDP has the best antiwear performance followed closely by Mixed ZDDP, and then is Sec. ZDDP - 3, Sec. ZDDP - 1/Sec. ZDDP - 2, Sec. ZDDP -4. The antiwear performance of full formulated lubricating oil increases firstly and then decreases as the oxida- tion time increasing. The different antiwear performances become obvious due to the different thermal stability, Prim. ZD- DP has the best performance.