Synthesis of crosslinked PEG/IL blend membrane via one‐pot thiol–ene/epoxy chemistry

Poly(ethylene glycol) (PEG)‐based membranes have obtained considerable attentions for CO 2 separation for their promising CO 2 separation performance and excellent thermal/chemical resistance. In this work, a one‐pot thiol–ene/epoxy reaction was used to prepare crosslinked PEG‐based and PEG/ionic liquids (ILs) blend membranes. Four ILs of the same cation [Bmim] + with different anions ([BF 4 ] − , [PF 6 ] − , [NTf 2 ] − , and [TCM] − ) were chosen as the additives. The chemical structure, thermal properties, hydrophilicity, and permeation performance of the resultant membranes were investigated to study the ILs' effects. An increment in CO 2 permeability (~34%) was obtained by optimizing monomer ratios and thus crosslinking network structures. Adding ILs into optimized PEG matrix shows distinct influences in CO 2 separation performance depending on the anions' types, due to the different CO 2 affinities and compatibilities with PEG matrix. Among these ILs, [Bmim][NTf 2 ] was found the most effective in enhancing CO 2 transport by simultaneously increasing the solubility and diffusivity of CO 2 . © 2020 The Authors. Journal of Polymer Science published by Wiley Periodicals LLC. J. Polym. Sci. 2020 , 58 , 2575‐2585