Hydrofluoro Olefin Propellant in a Polyurethane Foam Composition

Abstract

A process and composition is described for the inclusion of polyether polyols in concentrations greater than 10% loading on the B-side formulation with a catalyst package less than 1% loading on the B-side formulation. In one specific example, the use of glycerin as a fluorine ion scavenger is utilized to improve performance of the polyurethane systems through a twelve-month shelf life.

What is claimed is: 
     
         1 . A two component low pressure polyurethane foam comprising:
 an A-side comprising:
 at least one diisocyanate, and 
 an HFO propellant; and 
   a B-side comprising:
 approximately 30-50% by weight of at least one polyester polyol; 
 approximately 10.40% by weight of at least one polyether polyol; 
 approximately 1-15% by weight of a triol or a polyol having a functionality ≥2 and having a molecular weight between approximately 90-1,500 Inclusive; 
 approximately 0.3-1% by weight of an amine catalyst; 
 approximately 0.3-1% by weight of a potassium-based catalyst; and 
 an HFO propellant. 
   
     
     
         2 . The polyurethane foam of  claim 1  wherein
 the triol is glycerin. 
 
     
     
         3 . The polyurethane foam of  claim 1  wherein
 The catalyst is selected from the group consisting of Polycat 12, Dabco TMR-20 and Dabco T-120. 
 
     
     
         4 . The polyurethane foam of  claim 1  wherein
 the HFO propellant is HFO-1234ze. 
 
     
     
         5 . The polyurethane foam of  claim 1  wherein
 a concentration of added water is less than 1% by weight. 
 
     
     
         6 . The polyurethane foam of  claim 1  wherein
 a catalytic decay ratio (gel) is <1.5. 
 
     
     
         7 . The polyurethane foam of  claim 1  wherein
 a catalytic decay ratio (tack-free) is <1.5. 
 
     
     
         8 . A process to extend the shelf-life of a low-pressure two-component polyurethane spray foam comprising the step of:
 adding approximately 1-15% by weight of a triol or a polyol having a functionality ≥2 and having a molecular weight between approximately 90-1,500 inclusive to a B-side,   the B-side further comprising:
 approximately 30-50% by weight of at least one polyester polyol; 
 approximately 10-40% by weight of at least one polyether polyol; 
 approximately 0.3-1% by weight of an amine catalyst; 
 approximately 0.3-1% by weight of a potassium-based catalyst; and 
 an HFO propellant; 
   the A-side further comprising:
 at least one dilsocyanate; and 
 an HFO propellant. 
   
     
     
         9 . The process of  claim 8  wherein
 the triol is glycerin. 
 
     
     
         10 . The polyurethane foam of  claim 8  wherein
 the catalyst is selected from the group consisting of Polycat 12, Dabco TMR-20 and Dabco T-120. 
 
     
     
         11 . The polyurethane foam of  claim 8  wherein
 the HFO propellant is HFO-1234ze. 
 
     
     
         12 . The polyurethane foam of  claim 8  wherein
 a concentration of added water is less than 1% by weight. 
 
     
     
         13 . The polyurethane foam of  claim 8  wherein
 a catalytic decay ratio (gel) is <1.5. 
 
     
     
         14 . The polyurethane foam of  claim 8  wherein
 a catalytic decay ratio (tack-free) is <1.5.