Preparation Of Imidazole Ionic Liquid-based Monolith And The Study Of Its Characterization

With the advancement of science and technology, high performance liquid chromatography(HPLC) as an important method for separation and analysis, which has become the necessary tools for these fields, such as food industry, environmental monitoring and medicine, etc. The chromatographic columns, as the “core” of the high performance liquid chromatography system, assume the responsibility of the separation results.Monolithic columns, were widely studied and used due to its excellent characteristics including simple preparation, good permeability and high diffusion mass transfer.In this article, a polymeric monolithic column was prepared by free radical copolymerization. In this process, the homemade 1-vinyl-3-butyl chloride ionic liquid(VBC-ILs), 1-dodecene(C12), and trimethylol propane triacrylate(TMPTA) were used as the co-monomers; ethylene dimethacrylate(EDMA) as the crosslinking agent; dodecanol as the porogen and 2, 2-azobisisobutyronitrile as the initiator. In order to obtain the good performance column, the proportions of polymerized solution were optimized. The internal structure of the polymer was investigated by the scanning electron microscopy; The porosity and the specific surface area was assayed by mercury porosimetry and nitrogen adsorption,respectively. The result indicated that the IL-monolithic column possessed high pore properties, permeability, and mechanical stability. Furthermore, the monolithic column was used as the stationary phase of reversed phase high performance liquid chromatography(RP-HPLC) to separate small molecules compounds and Lysozyme, and good results were obtained.Secondly, another kind of monolithic column based on ILs was prepared via the same way by using the VBC-ILs, C12, and butyl methacrylate(BMA) as the co-monomers,ethylene dimethacrylate(EDMA) as the crosslinking agent, dodecanol as the porogen, and 2,2-azobisisobutyronitrile as the initiator. The effects of conditions on the monoliths, such as ratio of functional monomer and the solubility of porogens, were investigated in detail,respectively. Moreover, a series of different kinds of small molecules were utilized toevaluate the chromatographic performance of the monolithic column.The results showed that monoliths based on ILs had more uniform structure, higher specific surface area. In addition, the chromatographic performance of the monolith in separation of small molecules was enhanced.