Study On Curing System Of Four-components HTPB Composite Propellants

HTPB composite propellant has become a large used propellant abroad and in as for its simple productive technics, low cost, low bulk viscidity, good anti-aging performance and high solid content etc. Because of HTPB composite propellant's good prosperity, now a lot of research has been taken on it. Most of them refer to HTPB propellant's performance improving and application. But there are still few reports about its curing mechanism. By the way, HTPB composite propellant's curing mechanism is more difficult for its complicated components and their inter-activity. So my research chooses the active hydrogen components from all propellant's components as one part of curing mechanism, studies their reactive activity in curing system of HTPB propellant by kinetics, mechanical performance, swell ratio in detail.Kinetics of hydroxyl-terminated polybutadiene (HTPB) / phenyl isocyanate (PI) ,bonding agent(BA-5)/PI and antioxidant H/PI were studied in toluene/dimethyl sulphoxide solution. The rate constants and the activation parameters were calculated. The results showed that the reactionary rate of these three active hydrogen components decreased in same condition, the sequence of reactive activity was in following order: amine of BA-5>HTPB>hydroxyl of BA-5 > antioxidant H.Then four different formulations composed of these active hydrogen agents were cured with TDI and were made into rubber sheets. The effects of active hydrogen components on curing process were investigated by measurement of uniaxial tensile properties and swell ratio. Variety of rubber sheets' mechanical properties and crosslink density proved the results of kinetics. The results also show that BA-5 and antioxidant H both can improve HTPB propellant' mechanical properties effectively. And it will be well applied in real technical process.In addition, the research' results, all active hydrogen components' reactive activity and activation energy, influence on HTPB composite propellant' mechanical properties and network structure will be as reference for the study of HTPB composite propellant' formulation and productive technics.