Facile one-pot preparation of an imidazolium embedded C8 hybrid monolith using polyhedral oligomeric silsesquioxane for capillary liquid chromatography

In this study, a novel imidazolium embedded C-8 hybrid monolithic column based on polyhedral oligomeric silsesquioxane (POSS) was developed. With 1-vinyl-3-octylimidazolium bromide (VOI) as functional monomer, POSS-methacryl substituted (POSS-MA) as crosslinker, and azodiisobutyronitrile (AIBN) as thermal initiator, the monolithic column was facilely prepared via a one-pot process. The prepared column was characterized by scanning electron microscopy, Fourier transform infrared spectrometry, thermogravimetric analysis, and elemental analysis, respectively. Due to the introduction of VOI to the POSS-based monolith, the column efficiency reached 124 000 theoretical plates per m for separation of alkylbenzenes, outperforming the previously reported pentafluorobenzyl imidazolium bromide modified POSS hybrid monolithic column. Furthermore, high-efficiency separation of polycyclic aromatic hydrocarbons, aromatic amines, and even phenolic isomers was also achieved. All these results suggest the potential merits of the prepared hybrid monolithic column for separation of small molecules.