Firestop material

Abstract

The invention relates to a firestop material consisting of a polymer foam, notably a polyurethane foam, containing flame-retardant means. This firestop material is characterized in that the flame-retardant means consist of means designed to form a charred layer on the foam surface, under the effect of a rise in the temperature of the material resulting from a fire, and are supplemented by at least one inorganic type flame retardant. The invention furthermore relates to a chemical composition intended, after expansion and drying, to form such a firestop material, and to a use of such a firestop material.

1 . A firestop material comprising:
 a polymer foam containing no halogenated compound; and   flame-retardants configured to form a cohesive charred layer on the foam surface, for a temperature corresponding to that of a fire, the flame retardants comprising:
 at least one physical charring agent configured to form, by itself and in the absence of any interaction with any other constituent of the firestop material, a charred layer, 
 at least one reactive charring agent configured to form, by reacting with the polymer of the foam, a charred layer on the material surface, and 
 at least one inorganic flame retardant comprising a mineral filler and a metal oxide whose decomposition, under the effect of a temperature corresponding to that of a fire, is endothermic, wherein the inorganic flame retardant is configured such that the mineral filler can melt at high temperature and form a skin and an endothermic-decomposition compound of the metal oxide stabilizes the skin, and 
   wherein the physical charring agent, the reactive charring agent and the inorganic flame retardant are configured to intervene at different stages of the attack by the fire or the temperature on the firestop material, successively as the temperature increases.   
     
     
         2 . The firestop material as claimed in  claim 1 , wherein the physical charring agent comprises at least one mineral chemical compound taking a foliated structure and able to exfoliate with the heat of a fire. 
     
     
         3 . The firestop material as claimed in  claim 2 , wherein the at least one mineral chemical compound is selected from the group consisting of vermiculite, mica, and graphite. 
     
     
         4 . The firestop material as claimed in  claim 2 , wherein the at least one mineral chemical compound comprises expansible graphite. 
     
     
         5 . The firestop material as claimed in  claim 1 , wherein the reactive charring agent is at least one organophosphate compound. 
     
     
         6 . The firestop material as claimed in  claim 1 , wherein the polymer foam is selected from the group consisting of a polyisocyanurate foam, a polyethylene foam, a PVC foam and a formophenolic foam. 
     
     
         7 . The firestop material as claimed in  claim 1 , wherein the polymer foam comprises a polyurethane foam made from at least one polyol and at least one isocyanate. 20 
     
     
         8 . The firestop material as claimed in  claim 7 , wherein the polyol is a polyol polyether or a polyol polyester. 
     
     
         9 . The firestop material as claimed in  claim 7 , wherein the polyol has a viscosity, at 25° C., ranging between 200 and 1000 mPa·s. 
     
     
         10 . The firestop material as claimed in  claim 7 , wherein the polyol is selected in such a way that the polymer foam is flexible. 
     
     
         11 . The firestop material as claimed  claim 8 , wherein the polyol polyether is based on molecules of a member selected from the group consisting of ethylene glycol, glycerin, amine, trimethylpropane, pentaerytritol, sucrose, sorbitol and saccharose attached to propylene oxide and/or ethylene oxide molecules. 
     
     
         12 . The firestop material as claimed in  claim 8 , wherein the polyol polyester is based on at least one polyacid selected from the group consisting of adipic, phthalic, maleic and succinic acid. 
     
     
         13 . The firestop material as claimed in  claim 7  wherein the isocyanate is a diisocyanate. 
     
     
         14 . A chemical composition intended, after expansion and drying, to form the firestop material as claimed in  claim 1  and containing the precursors of the polymer foam and the flame-retardants. 
     
     
         15 . A method, comprising caulking an opening intended to receive lines, sheaths or cables with the firestop material as claimed in  claim 1 . 
     
     
         16 . The firestop material as claimed in  claim 1 , wherein the firestop material is provided as a structural element, a covering element, an insulating element, a closing element, a furniture element, a fitting or a surface coating. 
     
     
         17 . The firestop material as claimed in  claim 2 , wherein the at least one mineral chemical compound is expansible at a temperature of a fire. 
     
     
         18 . The firestop material as claimed in  claim 1 , wherein the reactive charring agent is selected from the group consisting of a phosphate compound and a polyphosphate compound. 
     
     
         19 . A firestop material comprising:
 a polymer foam containing no halogenated compound; and   flame-retardants configured to form a cohesive charred layer on the foam surface, for a temperature corresponding to that of a fire, the flame retardants comprising:
 at least one physical charring agent configured to form, by itself and in the absence of any interaction with any other constituent of the firestop material, a charred layer, 
 at least one reactive charring agent configured to form, by reacting with the polymer of the foam, a charred layer on the material surface, and 
 at least one inorganic flame retardant comprising a mineral filler and a metal oxide whose decomposition, under the effect of a temperature corresponding to that of a fire, is endothermic, wherein the mineral filler is selected from the group consisting of a glass powder mixture and talc, and the metal oxide is selected from the group consisting of zinc borate, aluminium oxide and magnesium oxide, wherein the inorganic flame retardant is configured such that the mineral filler can melt at high temperature and form a skin and an endothermic-decomposition compound of the metal oxide stabilizes the skin, and 
   wherein the physical charring agent, the reactive charring agent and the inorganic flame retardant are configured to intervene at different stages of the attack by the fire or the temperature on the firestop material, successively as the temperature increases.   
     
     
         20 . The firestop material as claimed in  claim 7 , wherein the polyol has a viscosity, at 25° C., ranging between 400 and 650 mPa·s. 
     
     
         21 . The firestop material as claimed in  claim 7 , wherein the polyol is selected in such a way that the polymer foam is rigid. 
     
     
         22 . The firestop material as claimed in  claim 7 , wherein the polyol is selected in such a way that the polymer foam has a shape memory or is visco-elastic. 
     
     
         23 . The firestop material as claimed in  claim 1 , wherein the physical charring agent is contained in an amount by mass of 13-22%, the reactive charring agent is contained in an amount by mass of 2-19%, and the inorganic flame retardant is contained in an amount by mass of 4-20%. 
     
     
         24 . The firestop material as claimed in  claim 1 , wherein the mineral filler is selected from the group consisting of a glass powder mixture and talc. 
     
     
         25 . The firestop material as claimed in  claim 7 , wherein the mineral filler is selected from the group consisting of a glass powder mixture and talc. 
     
     
         26 . The firestop material as claimed in  claim 1 , wherein the mineral filler does not include calcium silicate. 
     
     
         27 . The firestop material as claimed in  claim 7 , wherein the mineral filler does not include calcium silicate.