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

A novel energetic flame suppressant, 4-amino-3,5-dinitropyrazole potassium salt (ADNPK), was firstly synthesized with a yield of 86.26%. The structure of ADNPK was confirmed by IR and elemental analysis. The crystal structure of ADNPK was determined by single crystal X-ray diffractometer. It crystallizes in a monoclinic system, space group P2(1)/n with crystal parameters a = 12.706(3) Å, b = 9.3334(18) Å, c = 13.792(3) Å, β = 102.513(3)°, V = 1596.8(5) Å3, Z = 2, μ = 0.675 mm−1, F(0 0 0) = 928, and Dcalc = 1.907 g cm−3. The thermal behavior and non-isothermal decomposition reaction kinetics of ADNPK were studied by means of Differential Scanning Calorimetry (DSC). The apparent activation energy and pre-exponential factor of the exothermic decomposition reaction of ADNPK obtained by the Kissinger method are 237.3 kJ mol−1 and 1018.74 s−1. And the mechanism equation for the exothermic decomposition reaction of ADNPK is: d α d T = 10 18.74 β 2 ( 1 - α ) 3 / 2 exp ( - 2.37310 5 / RT ) .