Phosphorylation of phosphazenes and its effects on thermal properties and fire retardant behavior

Methods for the incorporation of phosphate and phosphonate units into the s ide groups of phosphazenes, at both the high polymeric and cyclic trimer le vels, are described and evaluated. Halogenated organophosphates were used a s the phosphorylating agents and were allowed to react with hydroxyl- or li thio-functionalized phosphazenes. Well-defined phosphorylated cyclic trimer s were synthesized from the hydroxyl-functionalized precursors, and these w ere examined as name-retardant additives to polystyrene. The thermal stabil ities of the high polymers made by this route were analyzed by TGA.