Aromatic polyesters, polyol blends comprising the same and resultant products therefrom

Abstract

The present invention discloses low viscosity aromatic polyester polyols suitable for blending with other polyols or other materials mutually compatible with the polyester polyols to achieve polyurethane and polyisocyanurate products. In particular the present invention discloses polyester polyols comprising the reaction of: A) an aromatic component comprising at 80 mole percent or greater of terephthalic acid; B) polyethylene glycol having a molecular weight from 150 to 1000; and C) a glycol different from the glycol of B); wherein A, B, and C are present in the reaction on a percent weight bases of 20 to 60 weight percent A); 40 to 75 weight percent of B); and 0 to 40 weight percent of C).

1 . A polyester polyol comprising the reaction product of:
 A) an aromatic component comprising at 80 mole percent or greater of terephthalic acid;   B) polyethylene glycol having a molecular weight from 150 to 1000; and   C) a glycol different from the glycol of B);   wherein A, B, and C are present in the reaction on a percent weight bases of 20 to 60 weight percent A); 40 to 75 weight percent of B); and 0 to 40 weight percent of C).   
     
     
         2 . The polyol of  claim 1  wherein the aromatic content comprises 85 mole percent or greater of terephthalic acid. 
     
     
         3 . The polyol of  claim 2  wherein the aromatic content comprises 95 mole percent or greater of terephthalic acid. 
     
     
         4 . The polyol of  claim 3  wherein the polyethylene glycol has a molecular weight of less than 500. 
     
     
         5 . The polyol of  claim 4  wherein component C) is presenting an amount from 1 to less than 30 weight percent of the reaction mixture. 
     
     
         6 . The polyol of  claim 1  wherein component C) is ethylene glycol, diethylene glycol, or a oxyalkylene glycol of the formula: 
       
         
           
           
               
               
           
         
         where R is hydrogen or a lower alkyl of 1 to 4 carbon atoms and n is from 1 to 5 with the proviso that at least 10 percent of the R moieties are a lower alkyl group. 
       
     
     
         7 . The polyol of  claim 6  wherein component C is ethylene glycol or diethylene glycol. 
     
     
         8 . An aromatic polyester polyol having a viscosity of less than 2500 mPa*s at 25° C. as measured by UNI EN ISO 3219 and a hydroxyl number of 200 to 400. 
     
     
         9 . The polyester of  claim 8  wherein the polyol has a viscosity of 2000 mPa*s or less. 
     
     
         10 . The polyester of  9  wherein 80 mole percent or more of the aromatic content of the polyester is derived from terephthalic acid. 
     
     
         11 . A polyol composition comprising from 10 to 90 weight percent of a polyol of  claim 1  and the remainder is at least one second polyol wherein the second polyol is a monol or polyether polyol having a functionality of 2 to 8 and a molecular weight of 100 to 10,000. 
     
     
         12 . The polyol composition of  claim 11  wherein the second polyol contains at least one polyol with a functionality of 2 to 6 and a hydroxyl number of 200 to 1,200. 
     
     
         13 - 16 . (canceled) 
     
     
         17 . A reaction system for production a rigid foam comprising a polyol composition of  claim 12  and a polyisocyanate. 
     
     
         18 . The reaction system of  claim 17  wherein the isocyanate is of the diphenylmethane-4,4′-diisocyanate series.