Insulation boards and methods for their manufacture

Abstract

A method for producing polyisocyanurate insulation foams, the method comprising contacting an A-side stream of reactants that includes an isocyanate with a B-side stream of reactants that include a polyol and a blowing agent, where the blowing agent includes isopentane and n-pentane in a substantial absence of cyclopentane.

1 . A method for producing polyisocyanurate insulation foams having dimensional stability, the method comprising:
 providing a blowing agent including isopentane and n-pentane in a substantial absence of cyclopentane, and having an isopentane to n-pentane weight ratio of from 2.7:1 to 1:1;   first combining and pressurizing a B-side stream of reactants, including a polyol and the blowing agent, under a pressure in excess of about 80 psi and at a temperature in excess of about 10° C.; and   then contacting an A-side stream of reactants that includes an isocyanate with the B-side stream of reactants.   
   
   
       2 . The method of  claim 1 , where said step of combining includes combining said polyol and said blowing agent within a dynamic pin mixer. 
   
   
       3 . The method of  claim 1 , where said step of contacting occurs within a mix head, where the B-side stream of reactants are at a temperature of about 29° C. to about 35° C. and a pressure of about 1,800 to about 2,400 psi, and where said A-side stream of reactants is at a temperature of about 29° C. to about 35° C. and a pressure of about 1,800 to about 2,400 psi. 
   
   
       4 . The method of  claim 1 , where the blowing agent includes at least about 90% by weight of the mixture of isopentane and n-pentane. 
   
   
       5 . The method of  claim 1 , where the blowing agent consists essentially of isopentane, n-pentane, and optionally at least one other blowing agent having a zero ozone depletion potential. 
   
   
       6 . The method of  claim 1 , where the amount of blowing agent employed is from about 10 to about 40 parts by weight blowing agent per 100 parts by weight polyol. 
   
   
       7 . The method of  claim 1 , where the polyol is preblended with at least one of a surfactant, water, a flame retardant, or a catalyst prior to contacting the polyol with the isocyanate compound. 
   
   
       8 . The method of  claim 1 , where the step of contacting mixes the A-side and B-side streams of reactants to form a mixture of polyisocyanurate ingredients, and further comprising depositing the mixture of polyisocyanurate ingredients onto a laminator and allowing the mixture of polyisocyanurate ingredients to form a developing foam. 
   
   
       9 . A method for producing polyisocyanurate insulation foams, the method comprising:
 high pressure mixing of a B-side stream of reactants, including a polyol and a blowing agent, under a pressure in excess of about 80 psi and at a temperature in excess of about 10° C., wherein the blowing agent agent includes isopentane and n-pentane in a substantial absence of cyclopentane, and wherein the blowing agent has an isopentane to n-pentane weight ratio of from 2.7:1 to 1:1; and   then contacting an A-side stream of reactants that includes an isocyanate with the B-side stream of reactants.   
   
   
       10 . The method of  claim 9 , where the B-side stream of reactants further includes water in an amount from about 0.1 to about 2.0 parts by weight per 100 parts polyol. 
   
   
       11 . The method of  claim 9 , where said step of contacting occurs within a mix head, where the B-side stream of reactants are at a temperature of about 29° C. to about 35° C. and a pressure of about 1,800 to about 2,400 psi, and where said A-side stream of reactants is at a temperature of about 29° C. to about 35° C. and a pressure of about 1,800 to about 2,400 psi. 
   
   
       12 . The method of  claim 9 , where the blowing agent includes less than 1.0 weight % cyclopentane. 
   
   
       13 . The method of  claim 9 , where the blowing agent includes less than 0.5 weight % cyclopentane. 
   
   
       14 . The method of  claim 9 , where the step of contacting mixes the A-side and B-side streams of reactants to form a mixture of polyisocyanurate ingredients, and further comprising depositing the mixture of polyisocyanurate ingredients onto a laminator and allowing the mixture of polyisocyanurate ingredients to form a developing foam.