Composition and method for preparing polyurethanes and polyurethane foams

Abstract

Polyurethane forming compositions having a water insoluble, non-hydrocarbon diluent provide polyurethanes with improved properties. Polyurethane forming reaction mixtures having a water insoluble diluent provide compositions that permit the formation of polyurethanes in the presence of excess water. Polyurethane forming reaction mixtures having a water insoluble diluent provide compositions that permit the formation of water-blown, low-density polyurethanes in the presence of excess water. Polyurethane forming reaction mixtures having a water insoluble diluent provide compositions that permit the formation of water-blown, low-density polyurethanes. Polyurethane forming compositions having a water insoluble, non-hydrocarbon diluent provide polyurethane foams with improved dimensional stability properties. Polyurethane forming compositions having a water insoluble, non-hydrocarbon diluent provide polyurethane elastomers in the presence of water.

We claim:  
     
         1 . A composition capable of forming dimensionally stable foam in wet environments, the composition comprising: 
 polyisocyanate;    polyether polyol;    blowing agent; and    ester diluent;    wherein the polyisocyanate, polyether polyol, and ester diluent comprise at least about 80% by weight of the total composition.    
     
     
         2 . The composition of  claim 1 , wherein polyisocyanate, polyether polyol, and ester diluent comprise at least about 97% by weight of the total composition.  
     
     
         3 . The composition of  claim 1 , wherein said ester diluent comprises a diester.  
     
     
         4 . The composition of  claim 1 , wherein said ester diluent comprises 2,2,4-trimethyl-1,3-pentanediol diisobutyrate.  
     
     
         5 . The composition of  claim 1 , wherein the ester diluent comprises between about 2% and about 21% by weight of the total composition.  
     
     
         6 . The composition of  claim 1 , wherein said ester diluent comprises a substantially non-water soluble ester.  
     
     
         7 . The composition of  claim 1 , wherein the foam has a volumetric change of less than about 15% after storing the foam for 28 days at 70° C. and 95% relative humidity.  
     
     
         8 . The composition of  claim 1 , wherein the foam has a volumetric change of less than about 10% after storing the foam for 28 days at 70° C. and 95% relative humidity.  
     
     
         9 . The composition of  claim 1 , wherein the foam has a volumetric change of less than about 5% after storing the foam for 28 days at 70° C. and 95% relative humidity.  
     
     
         10 . The composition of  claim 1 , wherein the foam has a volumetric change of less than about 0.4% after storing the foam for 28 days at 70° C. and 95% relative humidity.  
     
     
         11 . The composition of  claim 1 , wherein the foam has a density of less than about 5 pounds per cubic foot.  
     
     
         12 . The composition of  claim 1 , wherein the foam has a density of less than about 3 pounds per cubic foot.  
     
     
         13 . The composition of  claim 1 , wherein said blowing agent comprises water.  
     
     
         14 . The composition of  claim 13 , wherein said water comprises no more than about 2% by weight of the weight of polyisocyanate.  
     
     
         15 . The composition of  claim 13 , wherein said water comprises no more than about 5% by weight of the weight of polyisocyanate.  
     
     
         16 . The composition of  claim 1 , wherein said blowing agent comprises an organic blowing agent.  
     
     
         17 . The composition of  claim 1 , wherein said blowing agent comprises hydrofluorocarbons.  
     
     
         18 . The composition of  claim 1 , wherein said blowing agent comprises aliphatic hydrocarbons.  
     
     
         19 . The composition of  claim 1 , wherein said polyisocyanate comprises polymeric MDI.  
     
     
         20 . The composition of  claim 1 , wherein said polyisocyanate comprises a prepolymer.  
     
     
         21 . The composition of  claim 1 , wherein an isocyanate index ranges from about 0.9 to about 5.0.  
     
     
         22 . The composition of  claim 1 , wherein an isocyanate index ranges from about 1.05 to about 4.0.  
     
     
         23 . The composition of  claim 1 , wherein said polyether polyol comprises a mixture of polyhydroxyl compounds.  
     
     
         24 . The composition of  claim 1 , wherein said polyether polyol comprises a polyether polyol having a nominal molecular weight average between about 90 and about 6000, and a hydroxyl functionality between about 2 and about 6.  
     
     
         25 . The composition of  claim 1 , further comprising catalyst.  
     
     
         26 . The composition of  claim 25 , wherein said catalyst comprise between about 0.3 and about 1.0% by weight of the total composition.  
     
     
         27 . The composition of  claim 1 , further comprising organic tin catalyst.  
     
     
         28 . The composition of  claim 1 , further comprising tertiary amine catalyst.  
     
     
         29 . The composition of  claim 1 , further comprising amine polyol catalyst.  
     
     
         30 . The composition of  claim 1 , further comprising surfactant.  
     
     
         31 . The composition of  claim 1 , further comprising polyether polysiloxane surfactant.  
     
     
         32 . The composition of  claim 1 , wherein said polyisocyanate and said ester diluent are mixed prior to mixing with the remaining components.  
     
     
         33 . The composition of  claim 1 , wherein said polyether polyol and said ester diluent are mixed prior to mixing with the remaining components.  
     
     
         34 . The composition of  claim 1 , wherein the foam comprises a rigid polyurethane foam.  
     
     
         35 . The composition of  claim 34 , wherein the foam has a closed-cell content greater than 50% of the total cells.  
     
     
         36 . The composition of  claim 34 , wherein the foam has a closed-cell content greater than 70% of the total cells.  
     
     
         37 . The composition of  claim 34 , wherein the foam has a closed-cell content greater than 80% of the total cells.  
     
     
         38 . A method of stabilizing or reducing earth subsidence beneath a structure on a substrate with a polyurethane foam comprising: 
 mixing a composition of polyisocyanate, a polyether polyol, a blowing agent, and an ester diluent to form a reaction mixture, wherein the polyisocyanate, polyether polyol, and ester diluent comprise at least about 80% by weight of the total composition; and    injecting the reaction mixture into the substrate.    
     
     
         39 . The method of  claim 38 , wherein in the mixing step, the composition further comprises a tertiary amine catalyst.  
     
     
         40 . An improved method for leveling sunken or broken portions of earth supported floors and slabs, comprising the steps of: 
 mixing a composition of polyisocyanate, a polyether polyol, a blowing agent, and an ester diluent to form a reaction mixture, wherein the polyisocyanate, polyether polyol, and ester diluent comprise at least about 80% by weight of the total composition; and    injecting the reaction mixture beneath a sunken or broken portion of an earth supported floor or slab, whereby the expansion of said reaction mixture between said portion and the earth creates a mould pressure which raises said portion toward a position level with the remainder of said floor or slab.    
     
     
         41 . The method of  claim 40 , wherein in the mixing step, the composition further comprises a tertiary amine catalyst.  
     
     
         42 . A method of preparing a low density, rigid polyurethane foam, the method comprising: 
 (a) mixing components of a reaction mixture comprising: 
 (1) polyisocyanate;  
 (2) polyether polyol;  
 (3) water; and  
 (4) ester diluent;  
 wherein said polyisocyanate, polyether polyol, and ester diluent comprise at least about 80% by weight of the total composition; and  
   (b) allowing the reaction mixture to react and form the rigid polyurethane foam having density of less than about 5 pounds per cubic foot and a closed-cell content greater than 80% of the total cells.    
     
     
         43 . A composition for preparing a polyurethane foam, the composition consisting essentially of: 
 a polyisocyanate component;    a polyol component;    catalyst;    surfactant;    blowing agent; and    ester diluent.    
     
     
         44 . The method of  claim 41 , wherein polyisocyanate, polyol, and ester diluent comprise at least about 80% by weight of the total reaction mixture.  
     
     
         45 . The method of  claim 41 , wherein polyisocyanate, polyol, and ester diluent comprise at least about 97% by weight of the total reaction mixture.  
     
     
         46 . A method of stabilizing or reducing earth subsidence beneath a structure on a substrate with a water blown foam made in the presence of excess water comprising: 
 mixing polyisocyanate, polyether polyol having a quantity of water for generating carbon dioxide by reaction with a portion of the polyisocyanate, and 2,2,4-trimethyl-1,3-pentanediol diisobutyrate to form a reaction mixture; and    injecting the reaction mixture into the substrate.