Supercritical CO₂ Sizing and Desizing of Cotton Yarns

In this study, supercritical carbon dioxide (scCO₂) was evaluated as a sustainable medium for cotton yarn sizing and desizing, eliminating the need for water and organic solvents. Cellulose acetate was applied as the sizing agent, with acetone serving as a co-solvent, achieving a 10 % add-on comparable to conventional starch-sized yarns. Trials con-ducted at pressures of 15–20 MPa and temperatures of 40–60 °C demonstrated uniform size deposition and effi-cient removal during desizing, as confirmed by weight-gain distribution and friction testing. Mechanical characteri-zation revealed that scCO₂-sized yarns exhibited tensile strength and break elongation comparable to industry standards. The process also enabled near-complete recovery and reuse of acetone and CO₂, significantly reducing effluent generation and solvent consumption. These findings establish scCO₂-based sizing as a viable, eco-friendly alternative for the textile industry, offering both performance parity and enhanced sustainability.