Synthesis, crystal structure and thermal behavior of 4-amino-3,5-dinitropyrazole copper salt

Abstract

A novel energetic combustion catalyst, 4-amino-3,5-dinitropyrazole copper salt ([Cu(adnp)2(H2O)2]), was synthesized in a yield of 93.6% for the first time. The single crystal of [Cu(adnp)2(H2O)2] was determined by single crystal X-ray diffraction. It crystallizes in a triclinic system, space group P−1 with crystal parameters a = 5.541(3) Å, b = 7.926(4) Å, c = 10.231(5) Å, β = 101.372(8)°, V = 398.3(3) Å3, Z = 1, μ = 1.467 mm−1, F(0 0 0) = 243, and Dc = 2.000 g cm−3. The thermal behavior and non-isothermal decomposition reaction kinetics of [Cu(adnp)2(H2O)2] were studied by means of different heating rate differential scanning calorimetry (DSC). The kinetic equation of major exothermic decomposition reaction for [Cu(adnp)2(H2O)2] was obtained. The entropy of activation (ΔS≠), enthalpy of activation (ΔH≠), free energy of activation (ΔG≠), the self-accelerating decomposition temperature (TSADT) and the critical temperature of thermal explosion (Tb) are 59.42 J mol−1 K−1, 169.5 kJ mol−1, 1141.26 kJ mol−1, 457.3 K and 468.1 K, respectively.