The thermal behavior,mechanism and kinetic parameters of the first-stage exothermic decomposition reaction of the title compound in a temperature-programmed mode were investigated by means of DSC,TG-DTG and IR. The reaction mechanism has been proposed. The empirical kinetic model functions in differential forms,the apparent activation energy (E_a) and the pre-exponential factor(A)of this reaction are 1/3(1-α)［-ln(1-α)］^-2, 166.6 kJ·mol^-1 and 10^13.29 s^-1, respectively. The critical temperature of thermal explosion of the compound is 191.16 ℃. The values of ΔS^≠,ΔH^≠ and ΔG^≠ of the reaction are 50.8 J·mol^-1·K^-1,162.9 kJ·mol^-1 and 139.9 kJ·mol^-1,respectively.