A thermogravimetric study of phosphonium halides

The TG/DTG thermal curves for a series of phosphonium halides are presented. The stability of phosphonium salts increases in the order chloride < bromide ≈ iodide. While phosphonium salts with only nonpolar groups in the cation volatilize completely, increasing substitution by polar cyanoethyl groups results in residue formation. The kinetics of the thermal decomposition can be obtained using isothermal thermogravimetry.