Molded foams
Provided herein are catalyst combinations and processes useful for producing polyurethane foam products which have a greatly lessened tendency to emit vapors of residual amounts of catalysts, after prolonged storage of the foams even at elevated temperatures. According to one form of the invention, a reactive catalyst is used in combination with a polyol precursor wherein the polyol precursor has an unsaturation level that is below about 0.030 meq./g.
1 ) A process for producing a polyurethane foam comprising the steps of:
a) providing an organic polyol having a molecular weight in the range of 2000 to 7000, wherein said polyol has a level of unsaturation of between 0.001 and 0.030 meq./gram;
b) providing an organic isocyanate;
c) providing a blowing agent;
d) providing a reactive catalyst;
e) mixing said polyol, said isocyanate, and said blowing agent in the presence of said catalyst,
so as to produce a polyurethane foam.
2 ) A process according to claim 1 wherein said reactive catalyst comprises one or more catalysts selected from the group consisting of: (2-(2-(2-dimethylaminoethoxy-)ethyl methyl amino-)ethanol); (bis-(3-dimethylaminopropyl)-imino-propan-2-ol); (2-propanol, (1,1′-((3-(dimethylamino)propyl)imino)bis-; and (tetramethyliminobispropylamine).
3 ) A process according to claim 1 wherein said isocyanate is an organic di-isocyanate.
4 ) A process according to claim 3 wherein said organic di-isocyanate is selected from the group consisting of: toluene diisocyanate, diphenylmethane-4,4′-diisocyanate, polymerized isocyanates; aliphatic polyisocyanates; alicyclic polyisocyanates; pre-polymers with end isocyanate groups such as toluenediisocyanate pre-polymer and diphenylmethane-4,4′-diisocyanate pre-polymer which are obtained by the reaction of the above-mentioned substances with a polyol; denatured isocyanate such as carbodiimide denatured substances; and further mixed polyisocyanates thereof. Thus, the words “organic isocyanate” as used herein includes any and all of the aforesaid isocyanates, including mixtures thereof.
5 ) A process according to claim 1 wherein said blowing agent is selected from the group consisting of: butane, pentane, halogenated hydrocarbons, carbon dioxide, acetone, and water.
6 ) A process according to claim 5 wherein said blowing agent comprises a halogenated hydrocarbon present in any amount between 2.0 and 30 percent by weight of the total polyol used in making said polyurethane foam.
7 ) A polyurethane foam which contains a level of unsaturation of between 0.001 and 0.030 milliequivalents for every gram of polyol used in its manufacture.
8 ) A polyurethane foam which contains a level of unsaturation of between 0.005 and 0.025 milliequivalents for every gram of polyol used in its manufacture.
9 ) A polyurethane foam which contains a level of unsaturation of between 0.010 and 0.020 milliequivalents for every gram of polyol used in its manufacture.
10 ) A polyurethane foam produced by a process comprising the steps of:
a) providing an organic polyol having a molecular weight in the range of 2000 to 7000, wherein said polyol has a level of unsaturation of between 0.001 and 0.030 meq./gram;
b) providing an organic isocyanate;
c) providing a blowing agent;
d) providing a reactive catalyst;
e) mixing said polyol, said isocyanate, and said blowing agent in the presence of said catalyst,
so as to produce a polyurethane foam.
11 ) A process according to claim 10 wherein said reactive catalyst comprises one or more catalysts selected from the group consisting of: (2-(2-(2-dimethylaminoethoxy-)ethyl methyl amino-)ethanol); (bis-(3-dimethylaminopropyl)-imino-propan-2-ol); (2-propanol, (1,1′-((3-(dimethylamino)propyl)imino)bis-; and (tetramethyliminobispropylamine).
12 ) A process according to claim 10 wherein said isocyanate is an organic di-isocyanate.
13 ) A process according to claim 12 wherein said organic di-isocyanate is selected from the group consisting of: toluene diisocyanate, diphenylmethane-4,4′-diisocyanate, polymerized isocyanates; aliphatic polyisocyanates; alicyclic polyisocyanates; pre-polymers with end isocyanate groups such as toluenediisocyanate pre-polymer and diphenylmethane-4,4′-diisocyanate pre-polymer which are obtained by the reaction of the above-mentioned substances with a polyol; denatured isocyanate such as carbodiimide denatured substances; and further mixed polyisocyanates thereof. Thus, the words “organic isocyanate” as used herein includes any and all of the aforesaid isocyanates, including mixtures thereof.
14 ) A process according to claim 10 wherein said blowing agent is selected from the group consisting of: butane, pentane, halogenated hydrocarbons, carbon dioxide, acetone, and water.
15 ) A process according to claim 14 wherein said blowing agent comprises a halogenated hydrocarbon present in any amount between 2.0 and 30 percent by weight of the total polyol used in making said polyurethane foam.