Highly cross-linked cationic polymer microspheres as an efficient catalyst for facile CO₂ fixation

In this study, a new type of highly cross-linked cationic polymer microspheres was synthesized by a simple procedure of combining 1,2,4,5-tetrakis(bromomethyl)benzene and 4,4′-bipyridine. The influence of solvent used on the material structure and morphology was investigated and the obtained cationic polymers were fully characterized by FT-IR, BET, SEM, EDS, and TGA. Catalytic tests in the synthesis of cyclic carbonate from carbon dioxide (CO₂) and epoxides under mild conditions, along with comparisons to various counterparts, well demonstrate that the newly designed cross-linked cationic polymer with regular spherical structure exhibits high activity and selectivity, coupled with easy recovery and steadily reuse.