Development and Application of Cleaning Solvents for HTPB-Based Propellant Slurries

This article focuses on the cleaning of hydroxyl-terminated polybutadiene (HTPB)-based propellant slurries. On the basis of the theory of solubility parameters, a multidimensional development framework for ultrasonic cleaning solvents is established, integrating solubility parameter matching, polarity similarity principle, and safety performance evaluation. Through the comprehensive integration of molecular simulation technology and experimental methods, the interaction mechanism between various solvents and HTPB is deeply explored. By combining theoretical simulation calculations with viscosity method determination, the solubility parameter of HTPB is accurately obtained as 18.00 J^0.5 cm^−1.5. Solubility experiments, laser particle size analysis, and solvation free energy calculation reveal that 1-fluoro-1,1-dichloroethane (HCFC-141b) exhibits excellent dissolution performance for HTPB. To balance the cleaning effect and the safety of the ultrasonic process, HCFC-141b is used as the main solvent, with decane introduced for formulation optimization. The results show that the solvent prepared by mixing HCFC-141b and n-decane at a 1:1 volume ratio (v/v) exhibits a significant synergistic cleaning effect.