The high-temperature, high-pressure (HTHP) dyeing of polyester with disperse dyes faces challenges including process complexity, excessive wastewater, high energy demands, and ecological risks. This study developed a multifunctional dyeing auxiliary via ester interchange polycondensation, specifically optimized for HTHP polyester systems. The synthesized agent integrates dispersing, leveling, retarding, and postdyeing cleaning functionalities. Among the variants, DESI30 (DMT: SIPM = 7:3, M w = 28,283 Da) exhibited optimal performance, demonstrating exceptional thermal stability (maximum decomposition rate temperature >400°C) and interfacial activity. At 1.0 g/l, DESI30 reduced aqueous surface tension from 71.75 to 56.39 mN/m while maintaining stable foaming properties. It enhanced Disperse Orange 30 solubility (0.035 → 0.16 g/l at 0.50 g/l) and improved Disperse Red FB migration (CIE Δ E : 6.43 → 0.95 at 2.0 g/l). Washing-treatment with DESI30 (4.0 g/l, 80°C, 20 min) achieved level 4 staining fastness for Disperse Blue HRD (3.0% o.w.f.) on cotton/polyester. This auxiliary shortens dyeing cycles, reduces water and energy consumption, and offers a sustainable alternative for industrial polyester dyeing.
Liu et al. (2026) studied this question.