Hazard evaluation of self-decomposition materials by the combination of pressure and heat flux measurements

Thermal decomposition of unstable chemicals is always accompanied by heat release and gas generation. To ascertain such relationship, a heat flux calorimeter C80D fitted with a pressure-sensitive transducer provided simultaneous knowledge about pressure and heat flux behavior of a reactive agent. Consequently, (dP/dt)max was a parameter to reflect the characteristics of gas production potential during decomposition with the rate of reaction, which can be determined by thermal data, and was considered as a criterion to evaluate the hazardous characteristics for unstable substance. The results were compared with those in the UN standard PVT tests and the modified closed pressure vessel test (MCPVT), which have intense outer heating. It indicates that the decomposition measured in the C80D represents the inherent factor of materials and rate of reaction is the dominant factor to contribute to the intensity of the decomposition in other PVTs.