Research on crosslinking of epichlorohydrin and ionic liquids

Ionic liquid supported liquid membranes have shown high CO₂ selective separation performance, but their low pressure resistance greatly limits their industrial applications. From the viewpoint of high cost and complex synthesis of crosslinkers used for crosslinking ILs, preparing IL-based gels by crosslinking diamino protic ionic liquids (PILs) with epichlorohydrin (ECH) was proposed in this work. The feasibility of this conception was confirmed via monitoring dynamical information of reaction system. The effects of protonation, reaction temperature and ECH-to-PIL molar ratio on the conversion of epoxy and chloride groups were systematically investigated. The gel transition property of these crosslinked PILs and the possible crosslinking mechanism were studied. Moreover, CO₂ permeation performance in crosslinked ILs was preliminarily tested.