Design of Imidazolium-Based Poly(ionic liquids) for Multistep Integration Strategy Efficient Fixation of CO ₂ into a Chain Carbonate

The multistep conversion of CO₂ into high-value-added chemicals has emerged as a promising pathway for achieving carbon neutrality. However, this approach critically depends on catalysts with exceptional robustness and versatile functionality to overcome the inherent challenges of CO₂ activation and selectivity control. In this study, we successfully synthesized a series of imidazolium-based poly(ionic liquids) (Im-PILs) via conventional free radical polymerization. These polymeric catalysts exhibited exceptional bifunctional catalytic activity, enabling efficient promotion of both CO₂ cycloaddition and methanol transesterification reactions without the need for cocatalysts. Notably, their structural versatility and robust performance highlight their potential for sustainable catalytic applications in green chemistry. Under optimized reaction conditions, the catalytic system demonstrated outstanding performance, achieving nearly quantitative yields of 99.40% for propylene carbonate (PC) and 74.6% for dimethyl carbonate (DMC). Comprehensive structural characterization, combined with systematic comparative experiments, unequivocally confirmed the superior catalytic activity, exceptional recyclability (at least five cycles with <7% activity loss), and long-term stability of the Im-PILs. This work establishes a novel design paradigm for constructing porous catalytic systems that facilitate cost-effective CO₂ fixation, offering significant potential for industrial-scale carbon capture and utilization applications.