GB994087A - Improvements in or relating to rigid polyurethane materials - Google Patents

Abstract

A rigid cellular or non-cellular fire-retardant polyurethane comprises a compound of formula Ar(Br)m(Cl)nR or Ar(Br)m(Cl)nOR, where Ar is an aryl residue, m is 1 or more, n is 0 or an integer, R is hydrogen, a straight or branched alkyl or alkenyl group, an aryl or aralkyl group, there being in said compound at least two nuclear bromine atoms per molecule and the amount of said compound being such that it provides a bromine content of at least 0.5%. Compounds mentioned are: tetrabromobenzene, pentabromotoluene, tribromophenol, pentabromophenylethyl ether, pentabromophenyl-n-propyl ether, pentabromophenyl allyl ether, tribromotoluene, tribromophenyl allyl ether, chlorodibromotoluene, chlorodibromophenyl allyl ether, hexabromodiphenyl ether, dibromo - diphenyl, dibromonaphthalene or any isomer thereof, and 2:4-dibromo/methyl-naphthalene or 1:5 - dibromoanthracene. Antimony oxide or an organic antimonate, e.g. ethylene glycol antimonate or 1,2-propylene glycol antimonate may also be present. The polyurethane may be formed in the presence of the brominated organic compound. Conventional hydroxyl containing starting materials are listed in addition to phosphorus acid adducts of haloepoxides, e.g. the 3-chloro-1,2-epoxybutane adduct of orthophosphoric acid, and polyhydric alcohol adducts of polyhydroxy aliphatic phosphorus oxides, e.g. the ethylene glycol and pentaerythritol adducts of tris(hydroxymethyl)phosphine oxides. Suitable polyisocyanates include brominated isocyanates. In a typical Example (1) a foam was prepared from "Daltolac" polyester resin, water, "Suprasu" diisocyanate in which had been dispersed tribromophenyl allyl ether and Sb2O3.