Abstract:
Modified phosphazene fire retardants are prepared by reacting an organophosphazene with either a phosphonitrilic halide or a partially substituted organophosphazene. Similar materials are made by thermal treatment of the partially substituted materials. The reactant materials contain less than 38 weight per cent cyclics and are substantially composed of linear materials such that the number average molecular weight is from about 900 to about 400,000. The products are useful as fire retardants for cellulosics.