硅烷基咪唑双三氟甲烷磺酰亚胺离子液体气相色谱固定相的性能评价

以双三氟甲烷磺酰亚胺离子(NTf₂]^-)为阴离子,合成阳离子烷基取代不同(C1、C2和C4)的硅烷基咪唑离子液体,以其为固定相制备气相色谱填充柱。 硅烷基咪唑离子液体为强极性固定相;阳离子结构影响固定相的热稳定性、极性和分离性能。 在这些离子液体固定相中,1-丁基-3-(3-三甲氧基硅基)-丙基]咪唑双三氟甲烷磺酰亚胺(PBIM]NTf₂)对Grob试剂分离性能较好。 利用溶剂化作用参数模型,评价PBIM]NTf₂固定相特性,研究固定相-组分分子之间相互作用机制;同时考察PBIM]NTf₂色谱柱对不同类型化合物的分离性能。 结果表明,PBIM]NTf₂固定相主要作用力是氢键碱性和偶极作用,对烷烃、醇、酯和胺等不同类型的样品组分表现出良好的分离能力。

Evaluation of Silane Imidazolium Bis( trifluoromethane) sulfonimide Ionic Liquid Stationary Phase for Gas Chromatography

Silane imidazolium ionic liquids(ILs)with different alkyl substituted groups(C1,C2 and C4)on the cations and bis(trifluoromethane)sulfonimide ions(NTf 2]-)as the anions were synthesized as the stationary phase for packed column gas chromatography.The silane-based imidazolium ILs are strong polar stationary phases.The cation structure influences the thermal stability,polarity and separation properties.The separation behavior of 1-butyl-3-(3-trimethoxysilyl)-propyl]imidazolium bis(trifluoromethane)sulfonimide(PBIM]NTf 2)is better than that of other IL stationary phases.ThePBIM]NTf 2 stationary phase was further evaluated using solvation parameter model.The interaction mechanism between stationary phase and components as well as separation properties ofPBIM]NTf 2 column for different chemical compounds were investigated.The results indicate that hydrogen-bond basicity and dipole-dipole interactions as the main intermolecular forces exist betweenPBIM]NTf 2 and components.The stationary phase shows a good selectivity for the components such as Grob test mixture,alkanes,alcohols,esters and amines.