羟基脂肪酸在酯类油中的极压、抗磨性能

Investigation of the Extreme Pressure Antiwear Property of Hydroxy Fatty Acids in Ester Based Oil

利用ＭＲＳ１Ｊ机械式四球长时抗磨损试验机分别对顺式和反式二羧基两种立体构型羟基脂肪酸在合成酯中的极压、抗磨性能进行了研究．发现羟基脂肪酸在合成酯类油中具有一定的极压、抗磨作用，而且反式二羟基型的极压、抗磨效果优于顺式二羟基型．利用表面反射红外光谱分析了磨损实验后的磨痕表面，发现顺式二羟基羧酸极易吸附于摩擦表面，导致定向羟链缩短，吸附膜结构疏松，因而影响其极压和抗磨性能；而反式二羟基羧酸则在表面形成聚酯或聚醚结构．由此提出了两种立体构型羟基脂肪酸的不同的极压吸附抗磨模型．

The extreme pressure and antiwear(EP\|AW) properties of cis\| and trans\| dihydroxy, two types of stereoconfigurational fatty acids, was studied by use of the MRS\|1J four\|ball tester. The results show that hydroxy fatty acids possess some EP AW ability. Furthermore, the EP\|AW function of the fatty acid containing the trans\|dihydroxy group is better than that containing the cis\|dihydroxy group. The surface of wear scar was analyzed by Fourier transform infrared reflection absorption spectroscopy(FT\|IR RAS). It is found that the cis dihydroxy group can easily be adsorbed on the rubbing surface, which not only leads to the shortening of the linear aliphatic chain adsorbed on the surface, but also makes the film loose. Consequently, it has an adverse effect on the EP\|AW property. From the experimental results, the different adsorption EP\|AW models for the two types of hydroxy fatty acids were proposed. The models can well explain the experimental results and have a good help in developing novel hydroxy fatty acid based EP AW additives.