Thermal Runaway Risk Of Organic Peroxides In Polymerization Reactions

Organic peroxide is usually used as an initiator for monomer polymerization in industrial production.However,due to its unstable chemical properties and easy decomposition at high temperature,runaway thermal problems often occur,resulting in combustion and explosion accidents.It has serious impact on environmental safety.In this paper,the explosion hazard and thermal runaway risk of di-tert-butyl peroxide(DTBP)and tert-butyl peroxybenzoate(TBPB)in polymerization were studied,respectively.This study can provide technical support for reducing the environmental safety risk.The contents are as follows:The effects of concentration,initial temperature and heating rate on the spontaneous-combustion temperature,lower-explosion limit and initial-decomposition temperature of DTBP,TBPB were studied.The results showed that the auto-ignition temperature increased firstly and then decreased with the increasing of concentration.The lower-explosion limit of DTBP decreased with the increasing initial temperature.The initial-decomposition temperature of both organic peroxides increased with the increasing of heating rate.The effects of organic peroxides specity,initiator ratio and reaction temperature on methyl methacrylate(MMA)polymerization were investigated,respectively.The thermodynamic analysis of polymerization reaction was carried out.It was found that the optimal polymerization conditions were mass ratio(MMA: initiator of DTBP,TBPB)100:1,100:1.5,and the reaction temperature 120 ? and 110 ?,respectively.When the heating rate increased,the decomposition heat would increase with the increasing heating rate,resulting in increased reaction risk.With 5-Chloro-1-methyl-4-nitroimidazole/mesylate ionic liquid as additive,the optimal conditions for its interaction with DTBP and TBPB to initiate of MMA polymerization were investigated.The thermal decomposition characteristics were analyzed and compared with the thermal decomposition of DTBP and TBPB as initiators.It was found that the decomposition heat of the reaction could be much lowered after adding ionic liquid,thus the environmental safety risk could be avoided.