Halogen containing fire retardant additive with improved heat stability

A fire retardant polymeric composition comprising polymer selected from the group consisting of acrylonitrile-styrene-polybutadiene copolymers, polyurethanes, amino-formaldehyde resins and polyamides having recurring amide groups as integral parts of the main polymer chain and an effective fire retardant amount of a compound of the formula ##SPC6##

• wherein X is a halogen selected from the group consisting of fluorine, chlorine and bromine, Y is independently selected from the group consisting of fluorine, chlorine, bromine, alkyl of 1 to 10 carbon atoms, alkyloxy wherein the alkyl group contains 1 to 10 carbon atoms, haloalkyl and haloalkyloxy wherein said alkyl groups contain from 1 to 10 carbon atoms and said halo is fluoro, chloro or bromo, n has an average value from 0 to 6 and m has an average value from 0 to 6 and the total of n plus m has an average value from 1 to 6.