- Polyphosphazenes are a class of inorganic polymers with the repeat unit (-RR'P=N-). The substituents R,R' are usually alkoxy, amino, (R2N), or halogens (such as chloride or fluoride).
- Polyphosphazenes are typically prepared by the thermal ring-opening polymerization of hexachlorophosphazene (Cl2PN)3 followed by esterification of the intermediate poly(dichlorophosphazene) with either amines or sodium salts of alcohols.
- Most polyphosphazenes are colorless and exhibit high thermal stability, although they are somewhat sensitive to base hydrolysis.
- Polyphosphazenes are used as flame retardants, additives, performance polymers, and in specialty applications.