Synthesis polyphosphazenes with controlled molecular weight and polydisperity

摘要

A process for the preparation of polyphosphazenes is provided that includes the cationic solution polymerization reaction of a phosphoranimine, using a main group or transition metal halide, or other appropriate halide salt, including a linear phosphazene salt of any chain length, or a preformed non-phosphazene polymer containing a main or transition metal chloride, as an initiator. In a preferred embodiment, triarmed-star polyphosphazenes having the formula N{RN(H)R'2P-(N=PR'2)n}3 are prepared via this method. Also, a methods for synthesis of the monomer Cl3P=NSiMe3 and cyclic trimer N3P3X6 from the reactants N(SiR3)3 and PX5 are also described.