Flame retardant polyurethane foam

Abstract

Flame retardant polyurethane foams are prepared from compositions containing as flame retardant additives, a select group of halogenated phosphate esters.

What is claimed is:  .[.1. A polyether polyurethane foam prepared from a reaction mixture which comprises a flame retarding amount of a halogenated phosphate diester having the formula: ##STR2## wherein R is an aliphatic hydrocarbon radical having from 1 to about 8 carbon atoms, and each R' is independently a haloalkyl radical having from 
     
        1 to about 8 carbon atoms..]. .[.2.  The polyurethane foam of claim 1 wherein each of said haloalkyl radicals represented by R' contains 1 or 2 halogen atoms..]. .[.3. The polyurethane foam of claim 2 wherein all of said haloalkyl radicals represented by R' are identical, each such radical containing 2-4 carbon atoms..]. .[.4. The polyurethane foam of claim 3 wherein said radical represented by R is an aliphatic radical having from 1 to about 4 carbon atoms..]. .[.5. The polyurethane foam of claim 4 wherein said aliphatic radical contains 2-4 carbon atoms..]. .[.6. The polyurethane foam of claim 5 wherein each of said haloalkyl radicals represented by R' contains one halogen atom..]. .[.7. The polyurethane foam of claim 6 wherein said halogenated phosphate diester is selected from the group consisting of tetrakis(2-chloroethyl) ethylene diphosphate, tetrakis(2-bromoethyl) ethylene diphosphate, tetrakis(2-chloroethyl)-2,3-butene-1,4-diphosphate, tetrakis(2-chloroethyl) butylene diphosphate, and tetrakis(2chloroisopropyl) ethylene diphosphate..]. .[.8. The polyurethane foam of claim 7 wherein said halogenated phosphate diester is tetrakis(2-chloroethyl) ethylene diphosphate..]. .[.9. The polyurethane foam of claim 1 wherein said reaction mixture comprises a polyether polyol, an organic polyisocyanate, a foaming agent and a reaction catalyst..]. .[.10. A flexible polyurethane foam as claimed in claim 9 wherein said polyether polyol is an oxyalkylated polyhydric alcohol having a molecular weight of about 2000-7000..]. .[.11. The polyurethane foam of claim 10 wherein said R is an aliphatic radical having 2-4 carbon atoms, and all said haloalkyl radicals R' are identical..]. .[.12. The polyurethane foam of claim 11 wherein said haloalkyl radicals R' are monohaloalkyl having 1-4 carbon atoms..]. .[.13. The polyurethane foam of claim 12 wherein said organic isocyanate is toluene diisocyanate.  .[.14. The polyurethane foam of claim 13 wherein said halogenated phosphate diester is selected from the group consisting of tetrakis(2-chloroethyl) ethylene diphosphate, tetrakis(2-bromoethyl) ethylene diphosphate, tetrakis(2-chloroethyl)-2,3-butene-1,4-diphosphate, tetrakis(2-chloroethyl) butylene diphosphate, and tetrakis(2-chloroisopropyl) ethylene diphosphate..].  .[.15. The polyurethane foam of claim 14 wherein said oxyalkylated polyhydric alcohol has a molecular weight of about 2500-6000..]. .[.16. The polyurethane foam of claim 15 wherein said oxyalkylated polyhydric alcohol is oxypropylated glycerin..]. .[.17. The polyurethane foam of claim 16 wherein said reaction catalyst comprises stannous octoate..]. .[.18. The polyurethane foam of claim 17 wherein said reaction mixture also comprises a silicone surfactant..]. .[.19. The polyurethane foam of claim 18 wherein said foaming agent is water and wherein stannous octoate and triethylene diamine are employed as catalysts in said reaction mixture..]. .[.20. The polyurethane foam of claim 19 wherein said diester is 
     
     
        tetrakis(2-chloroethyl) ethylene diphosphate..]. .Iadd.21.  A polyurethane foam prepared from a reaction mixture comprised of a polyol, an organic polyisocyanate, a foaming agent, a reaction catalyst and a flame retardant additive consisting essentially of tetrakis(2-chloroethyl) ethylene diphosphate. .Iaddend. .Iadd.22. The polyurethane foam of claim 21 wherein from about 5 to about 30 parts of said tetrakis(2-chloroethyl) ethylene diphosphate are employed per 100 parts by weight of total polyol in said 
     
     
        reaction mixture. .Iaddend. .Iadd.23.  The polyurethane foam of claim 22 wherein from about 10 to about 25 parts of said tetrakis(2-chloroethyl) ethylene diphosphate are employed per 100 parts by weight of total polyol in said reaction mixture. .Iaddend. .Iadd.24. A polyurethane foam as claimed in claim 22 wherein said polyol is a polyether polyol having a hydroxyl number from about 25 to about 800. .Iaddend. .Iadd.25. A flexible polyurethane foam as claimed in claim 24 wherein said polyol is an oxyalkylated polyhydric polyol having a molecular weight from about 2500 to about 600. .Iaddend. .Iadd.26. The polyurethane foam of claim 25 wherein said organic polyisocyanate is toluene diisocyanate. .Iaddend. .Iadd.27. The polyurethane foam of claim 25 wherein said foaming agent is water. .Iaddend. .Iadd.28. The polyurethane foam of claim 25 wherein said reaction mixture comprises a surfactant. .Iaddend. .Iadd.29. The polyurethane foam of claim 28 wherein said organic polyisocyanate is toluene diisocyanate. .Iaddend. .Iadd.30. The polyurethane foam of claim 29 wherein said foaming agent is water. .Iaddend. .Iadd.31. The polyurethane foam of claim 30 wherein said oxyalkylated polyhydric alcohol is oxypropylated glycerin. .Iaddend. .Iadd.32. The polyurethane foam of claim 31 wherein said catalyts comprises stannous octoate and triethylene diamine and said surfactant is a silicone. .Iaddend.