Abstract: In order to study thermal decomposition characteristics, impact sensitivity of anhydrous and wet BPO, and discuss their relationship. Firstly, DSC tests and impact sensitivity tests at different ambient temperatures were carried. Then, based on the results of a series of dynamic and isothermal DSC tests, "autocatalytic + n order" model and "autocatalytic + autocatalytic + n order" model were established for decomposition under solid phase and melting process, and the hot spot temperatures of the above two conditions were predicted to be 244.7 and 277.9 ℃, respectively. Finally, the relationship between the characteristic drop height H₅₀ and the ambient temperature θ₀ was obtained according to the results of impact sensitivity tests. The results show that impact sensitivity of wet BPO is significantly lower than anhydrous BPO at 40 and 50 ℃, but the wet BPO is more sensitive to temperature at 40-70 ℃. Therefore, it is necessary to control temperature during transportation of wet BPO to reduce risk of explosion accidents caused by impaction.

Key words: benzoyl peroxide (BPO), differential scanning calorimetry (DSC), ambient temperature, thermal decomposition, impact sensitivity