Synthesis of poly(phenyltrifluoroethoxyphosphazene) by direct reaction of trimethylsilyl azide with bis(2,2,2-trifluoroethyl) phenylphosphonite

The reaction between bis(2,2,2-trifluoroethyl) phenylphosphonite and trimethylsilyl azide at temperatures from 70 to 120°C provides a mixture of bis(2,2,2-trifluoroethoxy)phenylN-(trimethylsilyl) phosphoranimine and poly(phenyl-2,2,2-trifluoroethoxyphosphazene). The polymer is probably formed by phosphine azide intermediates because the phosphor-animine is thermally stable up to 200°C. The polyphosphazene is an amorphous stereo-random polymer with a glass transition temperature at ?31°C.