Mechanical Properties and Thermal Decomposition Behaviors of Hydroxyl‐Terminated Polybutadiene/Glycerol Propoxylate Blend and Its Application to Ammonium Nitrate‐Based Propellants
Makoto Kohga, Ryoto Togashi
Abstract
Abstract Hydroxyl‐terminated polybutadiene (HTPB) is commonly used as a binder ingredient in composite propellants. In this study, a plasticizer was added to the binder to promote its plasticity and flexibility. Glycerol propoxylate (GPO) is a triol material with a zigzag structure, and it has one oxygen atom in a repeating unit. GPO would be a good plasticizer for HTPB binder to obtain good elasticity; furthermore, it would be suitable for improving the burning characteristics of the HTPB propellant. The addition of GPO to the HTPB binder was effective in extending the pot life and improving the mechanical properties of the propellant. The thermal decomposition behaviors of the HTPB/GPO blends were almost the same as that of the HTPB binder, except that the beginning consumption temperature of the blends was lower than that of HTPB. The ignitability at low pressure for the ammonium nitrate‐based propellant was improved by using the HTPB/GPO binder, whereas GPO did not enhance the burning rate of the propellant.