4-dichlorobenzoyl peroxide(DCBP)is usually used as an initiator
a hardener
and a vulcanizing agent in rubber industry.As a kind of organic peroxides
the peroxy group(-O-O-)may cause the thermal instability and explosion likelihood of DCBP.To analyze the potential hazards of its thermal decomposition
the differential scanning calorimetry(DSC)was used to test the thermal behavior of DCBP under dynamic and isothermal conditions.Kinetic parameters calculated by the Friedman iso-conversional method indicated the autocatalysis possibility of this decomposition.DSC curves obtained at five constant temperatures confirmed a strong autocatalytic reaction of DCBP.Exothermic onset temperature of DCBP was 98℃ and activation energy was between 232 kJ·mol-1 and 236 kJ·mol-1 under dynamic evaluation.When scanning at 92℃ in isothermal mode
the time to maximum rate was less than 30 min
so the best constant temperature for evaluation under this mode should be no higher than 92℃ to prevent loss of heat-flow signal.By simulating the five isothermal curves
a kinetic model was established and the mechanism function was found.As all data showed that reaction progress was short and reaction rate was high
it is best to avoid external heating and sudden energy transfer during DCBP manufacture
transportation and storage.Meanwhile
emergency rescue plans should be prepared for minimization of loss once accident happens.