聚α－烯烃基础油中抗氧剂N－苯基－α－萘胺的氧化动力学

摘要

模拟实际使用条件，研究抗氧剂N－苯基－α－萘胺（ NPAN）在聚α－烯烃（ PAO）基础油中的热氧化性能，结合FTIR技术分析200℃反应油样的结构组成，应用GC／MS评价抗氧剂N－苯基－α－萘胺（ NPAN）的热氧化衰变程度。结果表明，在PAO热氧化衰变过程中，其运动黏度值的变化与抗氧剂的含量有良好的相关性，随着抗氧剂的大量消耗，基础油开始急剧氧化，出现氧化失效现象； NPAN的热氧化反应为拟一级反应，抗氧剂的热氧化动力学规律可以很好地预测抗氧剂随反应时间及温度的消耗量，进而反映润滑油的热氧化衰变情况，为润滑油状况实时监控和及时掌握换油周期提供依据。%The thermal⁃oxidative reaction of antioxidant N⁃phenyl⁃α⁃naphthylamine(NPAN)in poly⁃α⁃olefins(PAO) was studied by simulating test.The composition and structure of oil samples after oxidation at 200℃were analyzed by FT⁃IR.The remaining content of antioxidant NPAN in PAO was measured by GC/MS.The results show that during thermal⁃oxi⁃dative degradation of PAO,the changes of the kinematic viscosity of PAO and NPAN remaining contents have good correla⁃tion.With the large consumption of antioxidants,PAO begins to oxidize quickly and phenomenon of oxidation failure occurs. The thermal⁃oxidative reaction of NPAN in this research is a pseudo⁃first order reaction.The kinetics of thermal oxidative degradation of NPAN can reveal the degrading of PAO,which provides basis for the quality monitoring of lubricating oils and the determination of reasonable drain intervals.