Supercritical fluids (SCFs) are substances that have been heated and pressurized above their critical temperature and pressure, exhibiting both gas-like and liquid-like properties. Supercritical CO₂ is the most widely used SCF for polymer synthesis due to its environmental friendliness, non-toxicity, and easy removal after processing. Supercritical CO₂ can be used as a medium for polymerization reactions or as a solvent for polymer processing, offering several advantages over traditional solvents.