• Solvent: The choice of solvent is another critical factor in CO₂-based polymerization. Solvents can influence the solubility of CO₂, the stability of intermediates, and the overall polymerization rate. Some solvents may facilitate better CO₂ activation, while others may inhibit the reaction or lead to the formation of impurities. Solvent-free polymerization (bulk polymerization) is often preferred to avoid environmental concerns associated with solvent use, but it may pose challenges in controlling reaction rates and product consistency .