Abstract
To understand the distribution behavior of brominated flame retardants (BFRs) such as polybromodiphenylethers, polybromophenols, and hexabromobenzene, and their related compounds in the environment, their physico-chemical properties are required. In this study, the water solubilities (Sw) at various temperatures and 1-octanol/water partition coefficients (Kow) for selected BFRs and their related compounds (brominated diphenylethers and brominated benzenes) were measured. These solubility data revealed not only the temperature dependence of Sw, namely enthalpy of solution, but also the effect of bromine substitution on Sw and the enthalpy of solution. Furthermore, the enthalpy of fusion and melting point for each of BFRs were measured by a differential scanning calorimetry method. These properties were used to determine the activity coefficients of these compounds in water using the measured Sw data. Henry's law constants of BFRs were also derived by assuming the obtained activity coefficients represent the infinite dilution activity coefficient. Finally, some additional physico-chemical characteristics of BFRs including brominated phenols were also discussed on the basis of basic structure and bromine substitution.
