Preparation,Crystal Structure And Properties Study Of Triazole And Tetrazole Energetic Complexes

Metal complexes have important research significance in many fields.A large number of energetic complexes can be prepared by selecting suitable ligands and metal salts,which can increase the energy density of conventional energetic materials and reduce the sensitivity of energetic materials.Seven energetic metal complexes were prepared by using 5-amino-1H-1,2,4-triazole-3-acetic acid?ATAA?and tetrazole?Tz?as ligands and transition metals salt,respectively.They are[Cu₃?ATAA?₃?H₂O?₇?OH?]?2NO₃,[M?ATAA?₂?H₂O?₂]?2H₂O?M=Zn,Cd?,[Zn?Tz?₂]_n and{[M₅?Tz?₉]?NO₃??6H₂O}_n?M=Zn,Cd,Mn?.The structure was characterized by infrared spectroscopy?IR?and elemental analysis?EA?.Single crystal of the above seven compounds was obtained by hydrothermal method and volatilization method,and their crystal structures were determined by X-ray single crystal diffraction?XRD?.The molecular formula of[Cu₃?ATAA?₃?H₂O?₇?OH?]?2NO₃ is C₁₂H₃₀N₁₄O₂₀Cu₃,which belongs to the triclinic crystal system and the space group is P-1;The molecular formula of[M?ATAA?₂?H₂O?₂]·2H₂O?M=Zn,Cd?is C₈H₁₈N₈O₈M,where[Cd?ATAA?₂?H₂O?₂]·2H₂O belongs to the triclinic system and the space group is P-1,the rest belong to the monoclinic system,and the space group is P2₁/n;The molecular formula of[Zn?Tz?₂]_n is C₂H₂N₈Zn,which belongs to the orthorhombic system,and the space group is Pbca;The molecular formula of{[M₅?Tz?₉]?NO₃??6H₂O}_n?M=Zn,Cd,Mn?is C₉H₂₁N₃₇O₉M₅,which belongs to the hexagonal system,and has a space group of P6₃/m.The catalytic combustion effect of triazole complexes on AP,CL-20 and HMX was measured by DSC.The thermal decomposition of four kinds of tetrazole complexes was studied by differential scanning calorimetry?DSC?and TG.By measuring the constant-volume combustion heat??_cU?and comparing their?_cU,it was found that[Zn?Tz?₂]_n>{[Mn₅?Tz?₉]?NO₃?·6H₂O}_n>{[Zn₅?Tz?₉]?NO₃?·6H₂O}_n>{[Cd₅?Tz?₉]?NO₃?·6H₂O}_n.According to Hess'law,the standard molar formation enthalpy(?_fH_m^?48?)was obtained from?_cU.The non-isothermal reaction kinetic parameters of the four complexes were calculated by Kissinger method and Ozawa method,and obtained the corresponding thermal decomposition kinetic mechanism function.Using thermal decomposition characteristic temperature and thermal decomposition kinetic parameters,some parameters related to these materials were calculated,such as self-accelerating decomposition temperature(T_e0),thermal explosion critical temperature(T_bp0),thermal ignition temperature(T_be0)and the activation entropy??S^??,the activation enthalpy??H^??and the activation free energy??G^??were evaluated for thermal safety.The detonation velocity and detonation pressure were calculated using the K-J formula and their sensitivities were tested to evaluate their detonation performance and safety.