Polyurethane foam

Abstract

A method of making a polyurethane foam from a mixture of isocyanate modified polyol and foam-forming ingredients, wherein the isocyanate modified polyol is made by reacting at least one polyol with at least one multifunctional isocyanate, wherein the isocyanate modified polyol is a non-foamed polyol polymer having available OH groups, wherein the foam forming ingredients comprise at least a multifunctional isocyanate and a foaming agent, preferably water, and characterised in that (i) the at least one polyol from which the isocyanate modified polyol is made comprises at least one lipid-based polyol which has undergone reaction with the isocyanate in the presence of a PU gelation catalyst, and/or (ii) the isocyanate modified polyol is mixed with a lipid-based polyol prior to, or at the same time as, foaming.

1 : A method of making polyurethane foam comprising a lipid-based polyol, the method including (a) making a prepolymer and then (b) making polyurethane foam using the prepolymer, the method comprising:
 (a) first making a prepolymer by a method comprising the steps of:   providing at least one lipid-based polyol, a first amount of multifunctional isocyanate, a first amount of at least one gelation catalyst, and optionally a petrochemical polyol; and   combining the lipid-based polyol, the first amount of isocyanate, the first amount of gelation catalyst, and also said petrochemical polyol when present, together to form a polyol/isocyanate blend;   reacting the polyol/isocyanate blend substantially without the use of added heat;   thereby creating a prepolymer, the prepolymer being substantially unfoamed, and having available unreacted OH functional groups; and   (b) making polyurethane foam using the prepolymer, the method comprising:   providing the prepolymer previously created in step (a); and   combining the prepolymer with a second amount of multifunctional isocyanate, with a foaming agent, optionally with a second amount of gelation catalyst, and optionally with petrochemical polyol; and   reacting the prepolymer, the second amount of isocyanate, the foaming agent, and said petrochemical polyol when present, in the presence of said second amount of gelation catalyst when present, thereby creating a polyurethane foam;   wherein the first amount of gelation catalyst is from 0.001 to 0.1 millimoles per each 100 grams of a total polyol component of the polyol/isocyanate blend;   wherein the first amount of multifunctional isocyanate is less than the stoichiometric amount of the multifunctional isocyanate(s) that would be required to react with all the available hydroxyl groups of the polyol(s) in the polyol/isocyanate blend; and   wherein the polyol/isocyanate blend comprises sufficient lipid-based polyol so that the total lipid-based polyol content of the polyurethane foam is not less than 20% relative to the total polyol content of the foam by weight.   
     
     
         2 : The method of  claim 1 , wherein the first amount of multifunctional isocyanate is in the range of from 0.01% to 33% of the stoichiometric amount of the multifunctional isocyanate(s) that would be required to react with all the available hydroxyl groups of the polyol(s) in the polyol/isocyanate blend. 
     
     
         3 : The method of  claim 1 , wherein the first amount of multifunctional isocyanate is in the range of from 3% to 25% of the stoichiometric amount of the multifunctional isocyanate(s) that would be required to react with all the available hydroxyl groups of the polyol(s) in the polyol/isocyanate blend. 
     
     
         4 : The method of  claim 1 , wherein the first amount of isocyanate comprises at least one of methylene diphenyl diisocyanate (MDI) and toluene diisocyanate (TDI). 
     
     
         5 : The method of making polyurethane foam of  claim 1 , wherein the lipid-based polyol provided and combined in the prepolymer step (a), and which is present in the final polyurethane foam, comprises soybean based polyol, palm oil based polyol, rapeseed oil based polyol, or a blend thereof. 
     
     
         6 : The method of making polyurethane foam of  claim 1 , wherein the prepolymer created in step (a) has a viscosity at 25 degrees Celsius of not more than 3,000 mPa·s. 
     
     
         7 : The method of  claim 1 , further comprising providing ricinoleic acid and adding the ricinoleic acid to the polyol/isocyanate blend. 
     
     
         8 : The method of  claim 1 , wherein the step of (a) making a prepolymer further comprises:
 providing a first amount of at least one petrochemical polyol in addition to said lipid-based polyol;   combining the petrochemical polyol with the lipid-based polyol, the first amount of multifunctional isocyanate, and the first amount of catalyst, to form the polyol/isocyanate blend; and   reacting the polyol/isocyanate blend to create a prepolymer;   wherein the prepolymer comprises substantially all of the polyol that is in the resulting polyurethane foam.   
     
     
         9 : The method of making polyurethane foam of  claim 1 , wherein the combining portion of step (b) making a polyurethane foam comprises combining the prepolymer with a second amount of multifunctional isocyanate, with a foaming agent, and also with a second amount of gelation catalyst; and
 wherein the reacting portion of step (b) comprises reacting the prepolymer, the isocyanate, and the foaming agent in the presence of the second amount of gelation catalyst, thereby creating a polyurethane foam.   
     
     
         10 : The method of making polyurethane foam of  claim 1 : wherein the polyol/isocyanate blend comprises sufficient lipid-based polyol so that the total lipid-based polyol content of the polyurethane foam is from 50% to 75% relative to the total polyol content of the foam by weight; and
 wherein the lipid-based polyol in the prepolymer and in the polyurethane foam consists essentially of soybean based polyol, palm oil based polyol, or a blend thereof.   
     
     
         11 : The method of making polyurethane foam of  claim 1 , wherein the polyol/isocyanate blend comprises sufficient lipid-based polyol so that the total lipid-based polyol content of the polyurethane foam is greater than 30% relative to the total polyol content of the foam by weight. 
     
     
         12 : The method of making polyurethane foam of  claim 1 , wherein the polyol/isocyanate blend comprises sufficient lipid-based polyol so that the total lipid-based polyol content of the polyurethane foam is greater than 50% relative to the total polyol content of the foam by weight. 
     
     
         13 : The method of making polyurethane foam of  claim 1 , wherein the polyol/isocyanate blend comprises sufficient lipid-based polyol so that the total lipid-based polyol content of the polyurethane foam is greater than 75% relative to the total polyol content of the foam by weight. 
     
     
         14 : The method of making polyurethane foam of  claim 1 , wherein the polyol/isocyanate blend comprises sufficient lipid-based polyol so that the total lipid-based polyol content of the polyurethane foam is greater than 90% relative to the total polyol content of the foam by weight. 
     
     
         15 : A method of making polyurethane foam comprising a lipid-based polyol, the method including (a) making a prepolymer and then (b) making polyurethane foam using the prepolymer, the method comprising:
 (a) first making a prepolymer by a method comprising the steps of:   providing at least one lipid-based polyol, a first amount of multifunctional isocyanate, at least one gelation catalyst, and optionally a petrochemical polyol; and   combining the lipid-based polyol, the first amount of isocyanate, the first amount of gelation catalyst, and also said petrochemical polyol when present, together to form a polyol/isocyanate blend;   reacting the polyol/isocyanate blend substantially without the use of added heat;   thereby creating a prepolymer, the prepolymer being substantially unfoamed, and having available unreacted OH functional groups; and   (b) making polyurethane foam using the prepolymer, the method comprising:   providing the prepolymer previously created in step (a); and   combining the prepolymer with a second amount of multifunctional isocyanate, with a foaming agent, optionally with a second amount of gelation catalyst, and optionally with petrochemical polyol; and   reacting the prepolymer, the second amount of isocyanate, the foaming agent, and said petrochemical polyol when present, in the presence of said second amount of gelation catalyst when present, thereby creating a polyurethane foam;   wherein the first amount of gelation catalyst is from 0.001 to 0.1 millimoles per each 100 grams of a total polyol component of the polyol/isocyanate blend; and   wherein the first amount of multifunctional isocyanate is in the range of from 0.01% to 33% of the stoichiometric amount of the multifunctional isocyanate(s) that would be required to react with all the available hydroxyl groups of the polyol(s) in the polyol/isocyanate blend.   
     
     
         16 : The method of making polyurethane foam of  claim 15 , wherein the polyol/isocyanate blend comprises sufficient lipid-based polyol so that the total lipid-based polyol content of the polyurethane foam is at least 7% relative to the total polyol content of the foam by weight. 
     
     
         17 : The method of making polyurethane foam of  claim 15 , wherein the polyol/isocyanate blend comprises sufficient lipid-based polyol so that the total lipid-based polyol content of the polyurethane foam is at least 16% relative to the total polyol content of the foam by weight. 
     
     
         18 : The method of making polyurethane foam of  claim 15 , wherein the combining portion of step (b) making a polyurethane foam comprises combining the prepolymer with a second amount of multifunctional isocyanate, with a foaming agent, and also with a second amount of gelation catalyst; and
 wherein the reacting portion of step (b) comprises reacting the prepolymer, the isocyanate, and the foaming agent in the presence of the second amount of gelation catalyst, thereby creating a polyurethane foam.   
     
     
         19 : The method of  claim 15 , wherein the step of (a) making a prepolymer further comprises:
 providing at least one petrochemical polyol in addition to said lipid-based polyol;   combining the petrochemical polyol with the lipid-based polyol, the first amount of multifunctional isocyanate, and the first amount of gelation catalyst, to form the polyol/isocyanate blend; and   reacting the polyol/isocyanate blend to create a prepolymer;   wherein the prepolymer comprises substantially all of the polyol that is in the resulting polyurethane foam.   
     
     
         20 : A method of making polyurethane foam comprising a lipid-based polyol, the method including (a) making a prepolymer and then (b) making polyurethane foam using the prepolymer, the method comprising:
 (a) first making a prepolymer by a method comprising the steps of:   providing at least one lipid-based polyol, a first amount of multifunctional isocyanate, at least one gelation catalyst, and optionally a petrochemical polyol; and   combining the lipid-based polyol, the first amount of isocyanate, the gelation catalyst, and also said petrochemical polyol when present, together to form a polyol/isocyanate blend;   reacting the polyol/isocyanate blend;   thereby creating a prepolymer, the prepolymer being substantially unfoamed, and having available unreacted OH functional groups; and   (b) making polyurethane foam using the prepolymer, the method comprising:providing the prepolymer previously created in step (a); and   combining the prepolymer with a second amount of multifunctional isocyanate, with a foaming agent, optionally with a second amount of gelation catalyst, and optionally with petrochemical polyol; and   reacting the prepolymer, the second amount of isocyanate, the foaming agent, and said petrochemical polyol when present, in the presence of said second amount of gelation catalyst when present, thereby creating a polyurethane foam;   wherein the first amount of multifunctional isocyanate is less than the stoichiometric amount of the multifunctional isocyanate(s) that would be required to react with all the available hydroxyl groups of the polyol(s) in the polyol/isocyanate blend;   wherein the polyol/isocyanate blend comprises sufficient lipid-based polyol so that the total lipid-based polyol content of the polyurethane foam is not less than 20% relative to the total polyol content of the foam by weight.