Evaporation and thermal degradation of tetrabromobisphenol A above the melting point

The volatility and the thermal degradation process of tetrabromobisphenol A (TBBA) were investigated. The quantitative assessment of the thermal degradation process and of the evaporation rate of TBBA required the use of an integrated approach, based on different calorimetric and analytical techniques. TBBA decomposition was carried out at temperatures between 180 and 270 °C, using thermogravimetric (TG) devices and a laboratory-scale batch reactor. The identification and quantification of decomposition products was based on GC and GC/MS techniques. The apparent kinetic parameters for TBBA decomposition were obtained, and a simplified method was used for a rough estimate of the vapor pressure from TG data. Thermal degradation of TBBA, although present even at temperatures as low as 185 °C, becomes relevant only above 230 °C. A preliminary evaluation of the Antoine correlation parameters for TBBA showed that the vapor pressure of this compound is comprised between 0.1 and 5 Pa at temperatures between 180 and 270 °C. The results obtained confirmed that TBBA processing at temperatures above the melting point (180 °C) may cause the release of TBBA in the environment due to evaporation phenomena.