One-part adhesive composition for adhering polymeric roofing membranes to roof deck substrates

Abstract

The present invention relates to a one component adhesive for adhering polymeric membranes to roof substrates. The one component adhesives are comprised of the reaction product of an isocyanate and a mixture of a compound having an average of two isocyanate reactive functional groups and a compound having an average of three isocyanate reactive functional groups.

1 . A one component, moisture curable, isocyanate terminated adhesive composition for adhering a polymeric sheet to a substrate, comprising the reaction product of; 
 A. an organic isocyanate containing compound having an average isocyanate functionality of at least two.    B. A mixture of a compound having an average of two isocyanate reactive functional groups and a compound having an average of three isocyanate reactive functional groups,    C. optionally a tackifier, and    D. optionally a solvent    where the equivalent ratio of the compound having an average of two isocyanate reactive functional groups and the compound having an average of three isocyanate reactive functional groups is from about 16:1 to about 1:4.    
     
     
         2 . The composition of  claim 1  further comprising, a catalyst.  
     
     
         3 . The composition of  claim 1  further comprising, an inhibitor.  
     
     
         4 . The composition of  claim 1  further comprising, a plasticizer.  
     
     
         5 . The composition of  claim 1  further comprising, a flow control agent.  
     
     
         6 . The composition of  claim 1  further comprising, a wetting agent.  
     
     
         7 . The composition of  claim 1  further comprising, a polyisocyanate crosslinker.  
     
     
         8 . The composition of  claim 1  wherein the organic isocyanate containing compound is a polymeric diphenylmethane diisocyanate.  
     
     
         9 . The composition of  claim 1  wherein the mixture comprises a simple diol and a simple triol.  
     
     
         10 . The composition of  claim 1 , wherein the mixture comprises a polyether polyol, a polyester polyol, a hydroxy terminated hydrocarbon or mixtures thereof.  
     
     
         11 . The composition of  claim 1 , wherein the tackifier is one or more rosin derivatives, coumarone-indene resins, terpene oligomers, aliphatic petroleum resins or alkyd modified phenolics.  
     
     
         12 . The composition of  claim 1 , wherein the solvent is one or more aromatic hydrocarbons, aliphatic hydrocarbons, ketones, esters, or halogenated hydrocarbons.  
     
     
         13 . A composite roof structure, comprising; 
 A. a roof deck,    B. a polymeric sheet, and    C. between the roof deck and the polymeric sheet the cured residue of a one component, isocyanate terminated adhesive composition, comprising the reaction product of; 
 i. an organic isocyanate containing compound having an average isocyanate functionality of at least two.  
 ii. A mixture of a compound having an average of two isocyanate reactive functional groups and a compound having an average of three isocyanate reactive functional groups,  
 iii. optionally a tackifier,  
 iv. optionally a polyisocyanate crosslinker, and  
 v. optionally a solvent  
 where the equivalent ratio of the compound having an average of two isocyanate reactive functional groups and the compound having an average of three isocyanate reactive functional groups is from about 16:1 to about 1:4.  
   
     
     
         14 . The roof structure of  claim 13 , wherein the polymeric sheet is selected from the groups consisting of chlorosulfonated polyethylene, polyvinyl chloride, thermoplastic polyolefin, copolymer alloy membrane and ethylene-propylene-diene-monomer.  
     
     
         15 . The roof structure of  claim 13 , where in the mixture is one or more polyether polyol, polyester polyol or hydrocarbon polyol.  
     
     
         16 . The roof structure of  claim 13 , wherein 
 A. the polymeric sheet is EPDM,    B. the mixture comprises; 
 i. a polyether polyol,  
 ii. a hydrocarbon polyol, and  
 iii. optionally a polyester polyol,  
   C. a tackifier,    D. a solvent, and    E. optionally a polyisocyanate crosslinker.    
     
     
         17 . The roof structure of  claim 13 , wherein  
     
     
         18 . The roof structure of  claim 13 , wherein, 
 A. the polymeric sheet is PVC, and    B. the mixture comprises; 
 i. a polyether polyol, and  
 ii. a polyester polyol.  
   
     
     
         17 . The roof structure of  claim 13 , wherein, 
 A. the polymeric sheet is TPO, and    B. the mixture comprises; 
 i. a polyether polyol,  
 ii. a polyester polol, and  
 iii. a hydrocarbon polyol, and  
   C. optionally a solvent.    
     
     
         18 . A method of preparing a composite roof structure, comprising; adhering a polymeric sheet to a roof deck with the cured residue of the adhesive of  claim 1.