Bonding agents for AP and nitramine/HTPB composite propellants

Chemical Modification of Hydroxyl-Terminated Polybutadiene and Its Application in Composite Propellants

“…From the above results, it can be seen that the addition of AEHTPB effectively inhibited the low-temperature-decomposition process of AP. Accordingly, in combination with all our observations, we put forward the mechanism of inhibiting the decomposition of AP: First, the AEHTPB molecule contains tertiary amine groups, which can react with the surface of AP particles to form ammonium salt ion bonds and release ammonia. , The reaction formula is as follows: …”

“…Accordingly, in combination with all our observations, we put forward the mechanism of inhibiting the decomposition of AP: First, the AEHTPB molecule contains tertiary amine groups, which can react with the surface of AP particles to form ammonium salt ion bonds and release ammonia. 50,51 The reaction formula is as follows: In the meantime, the AEHTPB molecules are firmly adsorbed on the AP surface by the bonding effect of ionic bonds, forming a dense coating layer, and this transition layer temporarily prevents the buildup of a perchloric acid shell on the AP surface during LTD (that is, inhibits the desorption of NH 3 ) (Figure 8). By contrast, the interfacial interaction between HTPB and AP is weak, and the relatively loose adsorption layer formed by the HTPB cannot prevent the desorption of ammonia.…”

Enantioselective synthesis of aziridines using asymmetric transfer hydrogenation as a precursor for chiral derivatives used as bonding agent for rocket solid propellants

“…In the diagram below are illustrated the hypothetical interaction between AP and the bonding agents (5) and (6) 5a,5b . While racemic aziridines and their derivatives are readly available, procedures for their synthesis in enantiomerically pure form are limited.…”

“…Up to the present, many aziridine derivatives have been tested and two of them, (5) and (6), have been used very successfully. 7 Compound (5) is a phosphorus aziridine tris[1-(2-methyl)-aziridinyl]phosphine oxide (MAPO) and (6) is an aromatic aziridine isophthalic 2-methyl aziridine (HX-752).…”

“…Some aziridine derivatives are also known as bonding agents for solid propellants which have a high potential to improve the mechanical properties of the propellant grains composed of the fuelbinder, hydroxyl terminated polybutadiene (HTPB) and the solid fillers, ammonium perchlorate (AP) and aluminium powder 5 . Nema 6 described the main function of the bonding agent as the enhancement of the adhesive force due to either the primary chemical tie of the functional groups to AP or the secondary polar attraction.…”