Methods for designing polyisocyanurate foam-forming compositions, related polyisocyanurate foam-forming compositions, and foams produced thereby

Abstract

Disclosed are methods for designing a polyisocyanurate foam-forming composition with good low temperature insulation performance. The methods include: (a) measuring the LTTR of a first polyisocyanurate faced foam laminate prepared from a first polyisocyanurate foam-forming composition comprising a blowing agent composition comprising one or more hydrocarbon blowing agents with an atmospheric pressure boiling point of at least 68° F. (20° C.), wherein the LTTR is measured according to CAN/UL S770-09 at a plurality of temperatures to identify a calculated inflection point temperature below which defines a first mathematical correlation between temperature and the LTTR of the first polyisocyanurate faced foam laminate and above which defines a second mathematical correlation between temperature and the LTTR of the first polyisocyanurate faced foam laminate; (b) identifying a plurality of predicted mathematical correlations between temperature and the LTTR of the first polyisocyanurate faced foam laminate at a plurality of reduced inflection point temperatures below the calculated inflection point temperature; and (c) using the plurality of predicted mathematical correlations identified in step (b) to design a second polyisocyanurate foam-forming composition that is different from the first polyisocyanurate foam-forming composition and which comprises a blowing agent composition comprising one or more hydrocarbon blowing agents with an atmospheric pressure boiling point of at least 68° F. (20° C.), wherein the second polyisocyanurate foam-forming composition produces a second polyisocyanurate faced foam laminate that has a LTTR of at least 5.4 ft2·hr·° F./BTU·inch (0.936 m2·° C./W@25 mm) at all mean insulation temperatures within a temperature range of 10° F. to 75° F. (−12.2° C. to 23.9° C.), when measured according to CAN/UL S770-09.

1 - 21 . (canceled) 
     
     
         22 . A polyisocyanurate faced foam laminate comprising a rigid foam that is the reaction product of a polyisocyanurate foam-forming composition comprising a blowing agent composition comprising (i) water and/or one or more hydrocarbons having an atmospheric pressure boiling point of less than 20° C., and (ii) one or more hydrocarbon blowing agents with an atmospheric pressure boiling point greater than or equal to 20° C., wherein the blowing agent composition is selected to provide a polyisocyanurate face rigid foam laminate having a LTTR of at least 5.4 ft 2 ·hr·° F./BTU·inch (0.936 m 2 ·° C./W@25 mm) at all mean insulation temperatures within a temperature range of 20° F. to 75° F. (−6.7° C. to 23.9° C.), when measured according to CAN/UL S770-09, the blowing agent composition is present in the foam-forming composition in an amount sufficient to make a foam having a core foam density of 1.50 to 1.80 lb/ft 3 , and the blowing agent composition is selected so that condensation of the blowing agent composition is calculated to occur when the average temperature of the foam is less than 40° F. 
     
     
         23 . The polyisocyanurate faced foam laminate of  claim 22 , wherein the polyisocyanurate foam-forming composition further comprises pMDI that is present in an amount of 55% to 75% by weight, based on total weight of the foam-forming composition. 
     
     
         24 . The polyisocyanurate faced foam laminate of  claim 22 , wherein the polyisocyanurate foam-forming composition further comprises an aromatic polyester polyol that is present in an amount of 25% to 35% by weight, based on total weight of the foam-forming composition. 
     
     
         25 . The polyisocyanurate faced foam laminate of  claim 22 , wherein the one or more hydrocarbon blowing agents with an atmospheric pressure boiling point greater than or equal to 20° C. is present in an amount of up to 6% by weight, based on the total weight of the foam-forming composition. 
     
     
         26 . The polyisocyanurate faced foam laminate of  claim 25 , wherein the one or more hydrocarbon blowing agents with an atmospheric pressure boiling point greater than or equal to 20° C. is present in an amount of at least 3% by weight, based on the total weight of the foam-forming composition. 
     
     
         27 . The polyisocyanurate faced foam laminate of  claim 26 , wherein the blowing agent composition comprises isopentane and n-pentane, wherein isopentane is present in an amount of no more than 4.71% by weight, based on the total weight of the foam-forming composition and n-pentane is present in an amount of no more than 3.37% by weight, based on the total weight of the foam-forming composition. 
     
     
         28 . The polyisocyanurate faced foam laminate of  claim 27 , wherein isopentane and n-pentane are present in a relative weight ratio of 70:30. 
     
     
         29 . The polyisocyanurate faced foam laminate of  claim 22 , wherein the blowing agent composition is selected so that condensation of the blowing agent composition is calculated to occur when the average temperature of the foam is between 40° F. and 30° F. 
     
     
         30 . The polyisocyanurate faced foam laminate of  claim 22 , wherein the polyisocyanurate face rigid foam laminate having a LTTR of at least 5.4 ft 2 ·hr·° F./BTU·inch (0.936 m 2 ·° C./W@25 mm) at all mean insulation temperatures within a temperature range of 10° F. to 75° F. (−12.2° C. to 23.9° C.). 
     
     
         31 . A method of making a polyisocyanurate faced foam laminate comprising:
 (a) conveying a lower fibrous facing layer along a production line;   (b) mixing an organic polyisocyanate and an isocyanate-reactive composition to form a foaming mixture, wherein a blowing agent composition is added as a separate stream to the isocyanate-reactive composition at a pressure of 1800 to 2500 psi via inline mixing and the resulting isocyanate-reactive composition is mixed with the organic polyisocyanate by impingement mixing in a mix head at a pressure of 1800 psi to 2500 psi;   (c) depositing the foaming mixture onto the lower fibrous facing layer as it is conveyed along the production line; and   (d) allowing the foaming mixture to expand and contact an advancing upper fibrous facing layer as it is conveyed along the production line, in which
 (1) the blowing agent composition comprises (i) water and/or one or more hydrocarbons having an atmospheric pressure boiling point of less than 20° C., and (ii) one or more hydrocarbon blowing agents with an atmospheric pressure boiling point greater than or equal to 20° C., 
 (2) the polyisocyanurate face rigid foam laminate has a LTTR of at least 5.4 ft 2 ·hr·° F./BTU·inch (0.936 m 2 ·° C./W@25 mm) at all mean insulation temperatures within a temperature range of 20° F. to 75° F. (−6.7° C. to 23.9° C.), when measured according to CAN/UL S770-09, 
 (3) the foam having a core foam density of 1.50 to 1.80 lb/ft 3 , and 
 (4) the blowing agent composition is selected so that condensation of the blowing agent composition is calculated to occur when the average temperature of the foam is less than 40° F. 
   
     
     
         32 . The method of  claim 31 , wherein the organic polyisocyanate comprises pMDI that is present in an amount of 55% to 75% by weight, based on total weight of the foaming mixture. 
     
     
         33 . The method of  claim 31 , wherein the isocyanate-reactive composition comprises an aromatic polyester polyol that is present in an amount of 25% to 35% by weight, based on total weight of the foaming mixture. 
     
     
         34 . The method of  claim 31 , wherein the one or more hydrocarbon blowing agents with an atmospheric pressure boiling point greater than or equal to 20° C. is present in an amount of up to 6% by weight, based on the total weight of the foaming mixture. 
     
     
         35 . The method of  claim 34 , wherein the one or more hydrocarbon blowing agents with an atmospheric pressure boiling point greater than or equal to 20° C. is present in an amount of at least 3% by weight, based on the total weight of the foaming mixture. 
     
     
         36 . The method of  claim 35 , wherein the blowing agent composition comprises isopentane and n-pentane, wherein isopentane is present in an amount of no more than 4.71% by weight, based on the total weight of the foam-forming composition and n-pentane is present in an amount of no more than 3.37% by weight, based on the total weight of the foam-forming composition. 
     
     
         37 . The method of  claim 36 , wherein isopentane and n-pentane are present in a relative weight ratio of 70:30. 
     
     
         38 . The method of  claim 31 , wherein the blowing agent composition is selected so that condensation of the blowing agent composition is calculated to occur when the average temperature of the foam is between 40° F. and 30° F. 
     
     
         39 . The method of  claim 31 , wherein the polyisocyanurate face rigid foam laminate having a LTTR of at least 5.4 ft 2 ·hr·° F./BTU·inch (0.936 m 2 ·° C./W@25 mm) at all mean insulation temperatures within a temperature range of 10° F. to 75° F. (−12.2° C. to 23.9° C.).