金属存在下聚α-烯烃基础油热氧化衰变性能结构对比分析

摘要

借助高温氧化模拟加速装置,模拟金属存在下聚α-烯烃(PAO)航空润滑油基础油高温工作环境,对比分析添加金属Cu前后油样的外观、黏度和酸值变化,利用GC/MS检测不同温度下油样的微观组成,并根据物质结构分析PAO理化性能变化的原因.结果表明:金属Cu加速了PAO的高温裂解,产生了某些生色化合物,加速了油品的氧化变质,使油品黏度降低,并生成了酸性物质使油品酸值增加;GC/MS分析结果表明,金属Cu的存在会加速PAO的氧化和裂解,产生碳数更少的烃分子,也促进含双键的不饱和烃、含氧化合物等物质的生成,在宏观上使油样运动黏度降低、酸值增大和颜色加深.%By means of high temperature thermal oxidation accelerated simulator,the high-temperature operating environment of PAO aviation lubricating oil in the presence of copper was simulated,and the variation of appearance,viscosity and acid value of PAO was analyzed before and after adding copper by contrast.The micro composition of samples under different temperature was detected by GC/MS,and the reason of the physical and chemical properties changes of PAO was analyzed according to the material structure.The result show that the high temperature cracking of PAO is accelerated in the presence of copper,some chromophores are produced,which accelerate the oxidation deterioration of PAO and make oil products kinematic viscosity reduced.The formation of acidic material results in the increasing of the acid value of PAO.The analysis results of GC/MS show that,the presence of copper will accelerate the oxidation and cracking of PAO,promote the formation of hydrocarbon molecules with less carbon number,and the substances such as unsaturated hydrocarbon containing double bonds and oxy-compounds.So the viscosity of the oil sample is decreased,the acid value is increased and the color is deepened.