Bifunctionalized conjugated microporous polymers for carbon dioxide capture

Abstract A novel kind of bifunctionalized conjugated microporous polymers containing sultone and hydroxyl groups has been synthesized via palladium-catalyzed Sonogashira–Hagihara cross-coupling reaction of bromophenol blue with 1,4-diethynylbenzene or 1,3,5-triethynylbenzene. The resulting polymers show high specific surface area up to 1470 m 2  g −1 and good thermal stability. BFCMP-2 exhibits a hydrogen uptake ability of 156 cm 3  g −1 (∼1.39 wt%) at 77 K/1.13 bar and a carbon dioxide uptake capacity of 2.77 mmol g −1 at 273 K/1.13 bar. Compared with most other reported non-functionalized conjugated microporous polymers, both of the bifunctionalized polymer networks show relatively high isosteric heat of CO 2 adsorption (25 kJ mol −1 ) due to the introduction of the polar functional groups of sultone and hydroxy enhanced the binding affinity between the polymer networks and CO 2 molecules. The results demonstrate that the introduction of strong polar groups into a polymer skeleton is an efficient strategy to produce CO 2 -philic microporous organic polymers with enhanced binding affinity with CO 2 molecules.