Ammonium dinitramide/glycidyl azide polymer (ADN/GAP) composite propellants with and without metallic fuels

Ammonium dinitramide/glycidyl azide polymer (ADN/GAP) composite propellants with or without metallic fuels are most likely candidates for a green alternative to ammonium perchlorate/hydroxyl-terminated polybutadiene (AP/HTPB) formulations. These ingredients are not only interesting in terms of environmental friendliness but also to overcome the intrinsic performance limitations of AP/HTPB. This paper describes some properties and the burning behavior of ADN/GAP-based propellants, as a function of ADN particles sizes and metallic fuel (Al, AlH3), regarding burning rate, pressure exponent, flame temperatures, particle temperatures, and agglomeration phenomena. Furthermore, aging properties and the formation of pores during sample preparation are discussed. A small-scale motor test of an ADN/GAP/Al propellant demonstrates the basic applicability of ADN/GAP-based formulations.