Polyalphaolefins (PAOs) are polymers produced from linear alpha olefins through catalytic oligomerization processes. The PAOs are known as synthetic high-performance base stock fluids used to improve the efficiency of many other synthetic products. In this study, we report the direct characterization of PAOs using atmospheric solid analysis probe (ASAP) coupled with ion mobility spectrometry-mass spectrometry (IMS-MS). We studied different PAOs grades exhibiting low- and high-viscosity index. Specific adjustments of the ASAP source parameters permitted the monitoring of ionization processes as three mechanisms could occur for these compounds: hydride abstraction, nitrogen addition, and/or the formation of [M−2H]^+• ions. Several series of fragment ions were obtained, which allowed the identification of the alpha olefin used to synthesize the PAO. The use of the ion mobility separation dimension provides information on isomeric species. In addition, the drift time versus m/z plots permitted rapid comparison between PAO samples and to evidence their complexity. These 2D plots appear as fingerprints of PAO samples. To conclude, the resort to ASAP-IMS-MS provides a rapid characterization of the PAO samples in a direct analysis approach, without any sample preparation.

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聚α烯烃（PAO）是由线性α烯烃通过催化低聚方法生产的聚合物。PAO被称为合成高性能基础油，用于提高许多其他合成产品的效率。在这项研究中，我们报告了使用大气固体分析探针（ASAP）结合离子淌度质谱-质谱（IMS-MS）进行PAO的直接表征。我们研究了表现出低粘度和高粘度指数的不同PAO等级。对ASAP源参数的特定调整允许监测电离过程，因为这些化合物可能发生三种机理：氢化物提取，氮添加和/或[M-2H] ^{+•的形成}离子。获得了几个系列的碎片离子，这使得可以鉴定用于合成PAO的α烯烃。离子迁移率分离维数的使用可提供有关异构体的信息。此外，漂移时间对m / z的图允许快速比较PAO样本并证明其复杂性。这些2D图显示为PAO样本的指纹。总而言之，诉诸ASAP-IMS-MS可以直接分析方法快速表征PAO样品，而无需任何样品前处理。

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