Synthesis and Properties of Two Energetic Salts Based on 1-Amino-2-nitroguanidine

Two nitrogen-rich energetic materials based on 1-amino-2-nitroguanidine were synthesized. The thermal behavior, thermodynamic properties, electron structures and detonation properties were investigated. The dynamic (DSC) curves show that 1-amino-2-nitroguanidinium 2,4,5-trinitroimidazole (salt 1) can be used as cast explosives. These curves allow determination of their melting points and thermodynamic parameters such as activation energy (E_k, salt 1, 282.1 kJ mol^–1; alt 2, 116.2 kJ mol^–1; E_o, salt 1, 275.0 kJ mol^–1; salt 2, 116.9 kJ mol^–1), entropy of activation (ΔS^≠, salt 1, 395.7 J mol^–1 K^–1; salt 2, 5.8 J mol^–1 K^–1), enthalpy of activation (ΔH^≠, salt 1, 278.7 kJ mol^‑1; salt 2, 113.1 kJ mol^–1), free energy of activation (ΔG^≠, salt 1, 117.6 kJ mol^–1; salt 2, 110.9 kJ mol^–1), heat of formation (∆H_f ⁰, salt 1, 264.7 kJ mol^–1; salt 2, 487.6 kJ mol^–1) and critical temperature of thermal explosion (T_b, salt 1, 412.3 K; salt 2, 388.9 K), suggesting that the synthesized salts are safe enough during storage or usage. In view of the detonation pressure (P, salt 1, 30.2 GPa; salt 2, 29.1 GPa) and detonation velocity (D, salt 1, 8398 m s^–1; salt 2, 8334 m s^–1), it is predicted that both 1-amino-2-nitroguanidine-based salts have the potential to be the useful energetic materials.

1-amino-2-nitroguanidine; energetic salts; thermodynamic properties; electronic structure; detonation properties