Synthesis, characterization, and propellant binder studies of new polyurethanes

Abstract

AbstractHydroxy‐terminated ether‐ and ester‐based prepolymers more suitable for propellant binder applications were prepared from tetrahydrofuran, propyleneoxide, and various discarboxylic acids. Polyurethanes were prepared from these prepolymers with various diisocyanates such as hexamethylenediisocyanate, toluene diisocyanate, and diphenylmethanediisocyanate, and the mechanical properties such as hardness, tensile strength, and elongation of these polyurethane elastomers were compared. The thermal degradation study of these polyurethanes was studied in the atmosphere of oxygen. Composite propellants were formed using these prepolymers as binder resins, toluene diisocyanate as the curing agent, ammonium perchlorate as the oxidizer, and aluminum as the fuel. Propellants having two different solid loadings (85 and 82%) were made and compared with respect to their unloading slurry viscosity and mechanical properties. The tensile strength, elongation, and ballistic performance parameters (theoretical) of these new propellant systems were promising.