Molecular Dynamics Study on Aging Mechanism of HTPB Propellants

In order to research the aging mechanism of HTPB propellants, molecular dynamics (MD) simulation method was used to study the aging mechanism of HTPB propellants after aging reaction. The changes of mechanical properties, binding energy, cohesive energy density and other properties of solid propellants were predicted when HMX was decomposed and HTPB was decomposed and oxidative cross-linked. So the aging mechanism of HTPB propellants can be speculated. The results show that during the long-term storage of propellant, HMX molecules will decompose and release gases. The retention of gases will greatly accelerate the aging of the propellant. However, in short-term storage, because HMX decomposition amount is less at room temperature, the effect on the performance is not obvious, so the decomposition of HTPB molecules is the main factor affecting the aging of propellant in short-term storage. The research content has certain guiding significance for the long-term storage of solid propellants.