硫化菜籽油的催化合成及其摩擦学特性

Catalyzed Synthesis and Tribological Behavior of Sulfurized Rapeseed Oil

以精制菜籽油为原料,天然丝光沸石为催化剂,研究了硫化菜籽油的催化合成,并借助FTIR测试技术分析了产物的化学结构。通过四球摩擦磨损试验机考察了其摩擦学性能,同时对磨痕表面进行了XPS及显微分析,探讨了其润滑机理。结果表明,随硫粉投料量的增大,菜籽油不饱和度逐渐降低,在丝光沸石催化下,硫化反应收率可达98%以上;含硫量从0增大到9.96%,硫化菜籽油的摩擦学性能明显提升,摩擦系数由0.085降为0.025,磨斑直径由0.56 mm降至0.42 mm,最大无卡咬负荷(PB值)由549 N升至745 N,烧结负荷(PD值)由1 960 N升至2 254 N;其润滑机理初步归结于硫化菜籽油在摩擦副表面上形成的吸附油膜,以及摩擦过程中由于摩擦化学反应形成的摩擦转移膜共同起减摩耐磨和极压作用。

Sulfurized rapeseed oil was synthesized v/a the reaction of refined rapeseed oil and sulfur in the presence of natural mordenite as a catalyst. The chemical structures of the products were analyzed by FTIR. The tribological performance of the sulfurized rapeseed oil was examined on a four-ball tribometer, and the lubrication mechanism was discussed by means of micrographs of wear scars and XPS. It was shown that the unsaturation degree decreased with increasing sulfur content. The reaction yield could exceed 98% in the presence of natural mordenite. The tribological performance of the rapeseed oil was improved with the sulfur content increased from zero to 9. 96%. The friction coefficient decreased from 0. 085 to 0. 025, the wear scar diameter decreased from 0. 56 mm to 0. 42 mm, the maximum non-seizure load （ PR value） increased from 549 N to 745 N, and the welding load （Po value） increased from 1 960 N to 2 254 N. The lubrication mechanism was ascribed to a lubrication film formed by the adsorption of the polar chain molecules and the tribological chemistry reaction of active sulfur element on the friction surface.