(423d) Experimental Study and Theoretical Analysis On Decomposition Mechanism of Benzoyl Peroxide

Benzoyl peroxide (BPO), a source of radical used as initiator, is an important member in the organic peroxide family. To master its thermal characters, experimental study and theoretical analysis were employed on studying its decomposition mechanism. The autocatalytic process, which was deduced from dynamic experimental data by differential scanning calorimeter (DSC), was testified by isothermal DSC tests. Thermal scanning unit (TSU) was taken to predict pressure hazard of BPO decomposition and accelerating rate calorimeter (ARC) tests were conducted to investigate the thermal behavior of BPO in adiabatic condition. The high pressure and fast pressure release rate indicated a high possibility of accompanied pressure hazard once the runaway decomposition was trigged. Combined with experimental results, quantum chemistry method was used to locate the most possible reaction path and calculate thermodynamic energies of BPO molecule in gas phase. The calculated total released heat during the whole decomposition was in good accordance with the values tested by thermal analysis instruments. And bond dissociation enthalpy (BDE) obtained at different theory levels provided a comparable value in runaway possibility analysis.