Foams And Foamable Compositions Containing Halogenated Olefin Blowing Agents

Abstract

The invention provides foam forming methods that comprise: (a) preparing a foamable system comprising at least one hydrohaloolefin; and (b) ensuring either (i) the substantial absence of long-term decomposition-inducing contact between said hydrofluoroolefin and an amine-containing catalyst; (ii) that an effective amount of surfactant is available in the system under conditions which prevent long term exposure of the surfactant to a long-term decomposition reaction environment; or (iii) a combination of (i) and (ii). Related methods, foamable systems and foams are also disclosed. Preferred embodiments provide polyurethane and polyisocyanurate foams and methods for the preparation thereof, including closed-celled, polyurethane and polyisocyanurate foams and methods for their preparation. The preferred foams are characterized by a fine uniform cell structure and little or no foam collapse. The foams are preferably produced with a polyol premix composition which comprises a combination of a hydrohaloolefin blowing agent, a polyol, a silicone surfactant, a catalyst and is further characterized by being substantially free of added water.

Claims

1. A foam forming method comprising: (a) preparing a foamable system comprising at least one hydrohaloolefin; and (b) ensuring (i) substantial absence of long-term decomposition-inducing contact between said hydrofluoroolefin and an amine-containing catalyst; or (ii) that an effective amount of surfactant is available in the system under conditions to prevent long term exposure of the surfactant to a long-term decomposition reaction environment; or (iii) a combination of (i) and (ii).

2. The method of claim 1 wherein said foamable system comprises an A side comprising a polyisocyanate and a B side comprising a polyol that is reactive with said polyisocyanate.

3. The method of claim 2 wherein said B side further comprises a catalytically effective amount of the amine-containing catalyst and hydrohaloolefin, which is generally decomposition reactive with said amine-containing catalyst.

4. The method of claim 3 wherein said ensuring step comprises ensuring that said B side contains a sufficient absence of a polar solvent to ensure that there is no substantial decomposition reaction between said hydrofluoroolefin and said amine after about two months of storage under ambient temperature conditions.

5. The method of claim 3 wherein said ensuring step comprises ensuring that said B side contains a sufficient absence of a polar solvent to ensure that there is no substantial decomposition reaction between said hydrofluoroolefin and said amine after about three months of storage under ambient temperature conditions.

6. The method of claim 3 wherein said ensuring step comprises ensuring that said B side contains a sufficient absence of a polar solvent to ensure that there is no substantial decomposition reaction between said hydrofluoroolefin and said amine after about six months of storage under ambient temperature conditions.

7. The method of claim 1 wherein said decomposition reactive hydrofluoroolefin comprises trans-1,3,3,3-tetrafluoropropene (HFO-1234ze(E)).

8. (canceled)

9. The method of claim 3 wherein said ensuring step comprises ensuring that said B side contains a sufficient absence of water to ensure that there is no substantial decomposition reaction between said hydrofluoroolefin and said amine after about three months of storage under ambient temperature conditions.

10. The method of claim 3 wherein said ensuring step comprises ensuring that said B side contains not more than about 1 weight % water.

11. The method of claim 3 wherein said ensuring step comprises ensuring that said B side contains not more than about 0.75 weight % water.

12. The method of claim 3 wherein said ensuring step comprises ensuring that said B side contains not more than about 0.5 weight % water.

13. A foam forming method comprising: (a) providing a foamable system comprising an A side and a B side, said B side comprising a catalytically effective amount of an amine-containing catalyst and at least one hydrohaloolefin that is generally decomposition reactive with said amine-containing catalyst; and (b) ensuring that said A side contains an effective amount of surfactant, optionally silicon-containing surfactant, to ensure the formation of insulating effective cells in the foam.

14. (canceled)

15. The foam forming method system of claim 13 wherein said B side is storage stable for a period of at least about 6 months.

16. (canceled)

17. (canceled)

18. (canceled)

19. The foam forming method of claim 13 wherein said B side is substantially free of polar solvents.

20. The foam forming method of claim 13 wherein a gas-generating co-blowing agent other than water is included in said A side, said B side, or both.

21. The foam forming method of claim 20 wherein said gas-generating co-blowing agent comprises formic acid.

22. A foam forming system comprising: at least a first composition and a second composition, and means for storing said first composition separate from said second composition, said first composition comprising at least one polyol and said second composition comprising at least one isocyanate reactive with said polyol, said system further comprising a decomposition reactive hydrohalocarbon and an amine-containing catalyst, each of said decomposition reactive hydrohalocarbon and said an amine-containing catalyst being independently contained in said first composition, said second composition, or in both of said compositions, provided that if a substantial portion of each of said reactive hydrohalocarbon and said amine-containing catalyst are contained in the same composition then that composition does not contain more than about 1 wt % of a polar solvent.

23. The foam forming method of claim 13 wherein if a substantial portion of each of said reactive hydrohalocarbon and said amine-containing catalyst are contained in the same composition then that composition does not contain more than about 1 wt % of water.

24. (canceled)

25. (canceled)

26. The foam forming method of claim 13 wherein said B side is storage stable for a period of at least about 2 months.

27. A foam formed from the method of claim 1.

28. A foam formed from the method of claim 13.

29. (canceled)

Description

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

[0024] Preferred aspects of the invention provide a polyol premix composition which comprises a combination of a blowing agent, one or more polyols, one or more silicone surfactants, and a catalyst, wherein the blowing agent comprises a hydrohaloolefin, and optionally a hydrocarbon, fluorocarbon, chlorocarbon, hydrochlorofluorocarbon, hydrofluorocarbon, halogenated hydrocarbon, ether, ester, alcohol, aldehyde, ketone, organic acid, gas generating material, or combinations thereof and wherein the polyol blend is has not greater than about 1 weight % water, preferably not more than 0.75 weight % water, and more preferably not more than 0.5 weight % water, and most preferably is substantially free of any added water. As used herein, the term substantially free of water means not including any water other than any water that may be an impurity in one of the other raw materials.

[0025] Another preferred embodiment of the invention provides a method of preparing a polyurethane or polyisocyanurate foam comprising reacting an organic polyisocyanate with the polyol premix composition and optionally adding water as a third chemical component.

[0026] The present invention in certain aspects provides a blowing agent that comprises a hydrohaloolefin, preferably comprising at least one of HFO-1234ze(E) and HFCO-1233zd(E), and optionally a hydrocarbon, fluorocarbon, chlorocarbon, fluorochlorocarbon, halogenated hydrocarbon, ether, fluorinated ether, ester, alcohol, aldehyde, ketone, organic acid, gas generating material (excluding water), or combinations thereof. The hydrohaloolefin preferably comprises at least one halooalkene such as a fluoroalkene or chlorofluoroalkene containing from 3 to 4 carbon atoms and at least one carbon-carbon double bond. Preferred hydrohaloolefins non-exclusively include trifluoropropenes, tetrafluoropropenes such as (HFO-1234), pentafluoropropenes such as (HFO-1225), chlorotrifloropropenes such as (HFO-1233), chlorodifluoropropenes, chlorotrifluoropropenes, chlorotetrafluoropropenes, and combinations of these. It is generally preferred that the compounds of the present invention are the tetrafluoropropene, pentafluoropropene, and chlorotrifloropropene compounds in which the unsaturated terminal carbon has not more than one F or Cl substituent. Included are 1,3,3,3-tetrafluoropropene (HFO-1234ze); 1,1,3,3-tetrafluoropropene; 1,2,3,3,3-pentafluoropropene (HFO-1225ye), 1,1,1-trifluoropropene; 1,2,3,3,3-pentafluoropropene, 1,1,1,3,3-pentafluoropropene (HFO-1225zc) and 1,1,2,3,3-pentafluoropropene (HFO-1225yc); (Z)-1,1,1,2,3-pentafluoropropene (HFO-1225yez); 1-chloro-3,3,3-trifluoropropene (HFCO-1233zd) or combinations thereof, and any and all stereoisomers of each of these.

[0027] The preferred hydrohaloolefins have a Global Warming Potential (GWP) of not greater than 150, more preferably not greater than 100 and even more preferably not greater than 75. As used herein, GWP is measured relative to that of carbon dioxide and over a 100-year time horizon, as defined in The Scientific Assessment of Ozone Depletion, 2002, a report of the World Meteorological Association's Global Ozone Research and Monitoring Project, which is incorporated herein by reference. Preferred hydrohaloolefins also preferably have an Ozone Depletion Potential (ODP) of not greater than 0.05, more preferably not greater than 0.02 and even more preferably about zero. As used herein, ODP is as defined in The Scientific Assessment of Ozone Depletion, 2002, A report of the World Meteorological Association's Global Ozone Research and Monitoring Project, which is incorporated herein by reference.

[0028] Preferred optional blowing agents non-exclusively include water, organic acids that produce CO2 and/or CO, hydrocarbons; ethers, halogenated ethers; esters, alcohols, aldehydes, ketones, pentafluorobutane; pentafluoropropane; hexafluoropropane; heptafluoropropane; trans-1,2 dichloroethylene; methylal, methyl formate; 1-chloro-1,2,2,2-tetrafluoroethane (HCFC-124); 1,1-dichloro-1-fluoroethane (HCFC-141b); 1,1,1,2-tetrafluoroethane (HFC-134a); 1,1,2,2-tetrafluoroethane (HFC-134); 1-chloro 1,1-difluoroethane (HCFC-142b); 1,1,1,3,3-pentafluorobutane (HFC-365mfc); 1,1,1,2,3,3,3-heptafluoropropane (HFC-227ea); trichlorofluoromethane (CFC-11); dichlorodifluoromethane (CFC-12); dichlorofluoromethane (HCFC-22); 1,1,1,3,3,3-hexafluoropropane (HFC-236fa); 1,1,1,2,3,3-hexafluoropropane (HFC-236e); 1,1,1,2,3,3,3-heptafluoropropane (HFC-227ea), difluoromethane (HFC-32); 1,1-difluoroethane (HFC-152a); 1,1,1,3,3-pentafluoropropane (HFC-245fa); butane; isobutane; normal pentane; isopentane; cyclopentane, or combinations thereof. The blowing agent component is usually present in the polyol premix composition in an amount of from about 1 wt. % to about 30 wt. %, preferably from about 3 wt. % to about 25 wt. %, and more preferably from about 5 wt. % to about 25 wt. %, by weight of the polyol premix composition. When both a hydrohaloolefin and an optional blowing agent are present, the hydrohaloolefin component is preferably present in the blowing agent component in an amount of from about 5 wt. % to about 90 wt. %, preferably from about 7 wt. % to about 80 wt. %, and more preferably from about 10 wt. % to about 70 wt. %, by weight of the blowing agent component; and the optional blowing agent is usually present in the blowing agent component in an amount of from about 95 wt. % to about 10 wt. %, preferably from about 93 wt. % to about 20 wt. %, and more preferably from about 90 wt. % to about 30 wt. %, by weight of the blowing agent component.

[0029] The polyol component, which may include mixtures of polyols, can be any polyol which reacts in a known fashion with an isocyanate in preparing a polyurethane or polyisocyanurate foam. Useful polyols comprise one or more of a sucrose containing polyol; phenol, a phenol formaldehyde containing polyol; a glucose containing polyol; a sorbitol containing polyol; a methylglucoside containing polyol; an aromatic polyester polyol; glycerol; ethylene glycol; diethylene glycol; propylene glycol; graft copolymers of polyether polyols with a vinyl polymer; a copolymer of a polyether polyol with a polyurea; one or more of (a) condensed with one or more of (b): (a) glycerine, ethylene glycol, diethylene glycol, trimethylolpropane, ethylene diamine, pentaerythritol, soy oil, lecithin, tall oil, palm oil, castor oil;(b) ethylene oxide, propylene oxide, a mixture of ethylene oxide and propylene oxide; or combinations thereof. The polyol component is preferably present in the polyol premix composition in an amount of from about 60 wt. % to about 95 wt. %, preferably from about 65 wt. % to about 95 wt. %, and more preferably from about 70 wt. % to about 90 wt. %, by weight of the polyol premix composition.

[0030] As mentioned above, the polyol premix composition preferably also contains at least one silicone-containing surfactant. The silicone-containing surfactant is used to aid in the formation of foam from the mixture, as well as to control the size of the bubbles of the foam so that a foam of a desired cell structure is obtained. Preferably, a foam with small bubbles or cells therein of uniform size is desired since it has the most desirable physical properties such as compressive strength and thermal conductivity. Also, it is critical to have a foam with stable cells which do not collapse prior to forming or during foam rise.

[0031] Silicone surfactants for use in the preparation of polyurethane or polyisocyanurate foams are available under a number of trade names known to those skilled in this art. Such materials have been found to be applicable over a wide range of formulations allowing uniform cell formation and maximum gas entrapment to achieve very low density foam structures. The preferred silicone surfactant comprises a polysiloxane polyoxyalkylene block co-polymer. Some representative silicone surfactants useful for this invention are Momentive's L-5130, L-5180, L-5340, L-5440, L-6100, L-6900, L-6980 and L-6988; Air Products DC-193, DC-197, DC-5582 , and DC-5598; and B-8404, B-8407, B-8409 and B-8462 from Goldschmidt AG of Essen, Germany. Others are disclosed in U.S. Pat. Nos. 2,834,748; 2,917,480; 2,846,458 and 4,147,847. The silicone surfactant component is usually present in the polyol premix composition in an amount of from about 0.5 wt. % to about 5.0 wt. %, preferably from about 1.0 wt. % to about 4.0 wt. %, and more preferably from about 1.5 wt. % to about 3.0 wt. %, by weight of the polyol premix composition.

[0032] The polyol premix composition may optionally contain a non-silicone surfactant, such as a non-silicone, non-ionic surfactant. Such may include oxyethylated alkylphenols, oxyethylated fatty alcohols, paraffin oils, castor oil esters, ricinoleic acid esters, turkey red oil, groundnut oil, paraffins, and fatty alcohols. A preferred non-silicone non-ionic surfactant is LK-443 which is commercially available from Air Products Corporation. When a non-silicone, non-ionic surfactant used, it is usually present in the polyol premix composition in an amount of from about 0.25 wt. % to about 3.0 wt. %, preferably from about 0.5 wt. % to about 2.5 wt. %, and more preferably from about 0.75 wt. % to about 2.0 wt. %, by weight of the polyol premix composition.

[0033] The inventive polyol premix composition preferably contains a catalyst or catalysts. Useful are primary amine, secondary amine or tertiary amine. Useful tertiary amine catalysts non-exclusively include N,N,N,N,N-pentamethyldiethyltriamine, N,N-dicyclohexylmethylamine; N,N-ethyldiisopropylamine; N,N-dimethylcyclohexylamine; N,N-dimethylisopropylamine; N-methyl-N-isopropylbenzylamine; N-methyl-N-cyclopentylbenzylamine; N-isopropyl-N-sec-butyl-trifluoroethylamine; N,N-diethyl-(-phenylethyl)amine, N,N,N-tri-n-propylamine, or combinations thereof. Useful secondary amine catalysts non-exclusively include dicyclohexylamine; t-butylisopropylamine; di-t-butylamine; cyclohexyl-t-butylamine; di-sec-butylamine, dicyclopentylamine; di-(-trifluoromethylethyl)amine; di-(-phenylethyl)amine; or combinations thereof. Useful primary amine catalysts non-exclusively include: triphenylmethylamine and 1,1-diethyl-n-propylamine.

[0034] Other useful amines includes morpholines, imidazoles, ether containing compounds, and the like. These include

dimorpholinodiethylether

N-ethylmorpholine

N-methylmorpholine

[0035] bis(dimethylaminoethyl) ether
imidizole
n-methylimidazole
1,2-dimethylimidazole
dimorpholinodimethylether
N,N,N,N,N,N-pentamethyldiethylenetriamine
N,N,N,N,N,N-pentaethyldiethylenetriamine
N,N,N,N,N,N-pentamethyldipropylenetriamine
bis(diethylaminoethyl) ether
bis(dimethylaminopropyl) ether.

[0036] The preparation of polyurethane or polyisocyanurate foams using the compositions described herein may follow any of the methods well known in the art can be employed, see Saunders and Frisch, Volumes I and II Polyurethanes Chemistry and technology, 1962, John Wiley and Sons, New York, N.Y. or Gum, Reese, Ulrich, Reaction Polymers, 1992, Oxford University Press, New York, N.Y. or Klempner and Sendijarevic, Polymeric Foams and Foam Technology, 2004, Hanser Gardner Publications, Cincinnati, Ohio. In general, polyurethane or polyisocyanurate foams are prepared by combining an isocyanate, the polyol premix composition, and other materials such as optional flame retardants, colorants, or other additives. These foams can be rigid, flexible, or semi-rigid, and can have a closed cell structure, an open cell structure or a mixture of open and closed cells.

[0037] It is convenient in many applications to provide the components for polyurethane or polyisocyanurate foams in pre-blended formulations. Most typically, the foam formulation is pre-blended into two components. The isocyanate and optionally other isocyanate compatible raw materials, including but not limited to blowing agents and certain silicone surfactants, comprise the first component, commonly referred to as the A component. The polyol mixture composition, including surfactant, catalysts, blowing agents, and optional other ingredients comprise the second component, commonly referred to as the B component. In any given application, the B component may not contain all the above listed components, for example some formulations omit the flame retardant if flame retardancy is not a required foam property. Accordingly, polyurethane or polyisocyanurate foams are readily prepared by bringing together the A and B side components either by hand mix for small preparations and, preferably, machine mix techniques to form blocks, slabs, laminates, pour-in-place panels and other items, spray applied foams, froths, and the like. Optionally, other ingredients such as fire retardants, colorants, auxiliary blowing agents, water, and even other polyols can be added as a stream to the mix head or reaction site. Most conveniently, however, they are all, with the exception of water, incorporated into one B component as described above.

[0038] A foamable composition suitable for forming a polyurethane or polyisocyanurate foam may be formed by reacting an organic polyisocyanate and the polyol premix composition described above. Any organic polyisocyanate can be employed in polyurethane or polyisocyanurate foam synthesis inclusive of aliphatic and aromatic polyisocyanates. Suitable organic polyisocyanates include aliphatic, cycloaliphatic, araliphatic, aromatic, and heterocyclic isocyanates which are well known in the field of polyurethane chemistry. These are described in, for example, U.S. Pat. Nos. 4,868,224; 3,401,190; 3,454,606; 3,277,138; 3,492,330; 3,001,973; 3,394,164; 3,124,605; and 3,201,372. Preferred as a class are the aromatic polyisocyanates.

[0039] Representative organic polyisocyanates correspond to the formula:

R(NCO).sub.z

wherein R is a polyvalent organic radical which is either aliphatic, aralkyl, aromatic or mixtures thereof, and z is an integer which corresponds to the valence of R and is at least two. Representative of the organic polyisocyanates contemplated herein includes, for example, the aromatic diisocyanates such as 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, mixtures of 2,4- and 2,6-toluene diisocyanate, crude toluene diisocyanate, methylene diphenyl diisocyanate, crude methylene diphenyl diisocyanate and the like; the aromatic triisocyanates such as 4,4,4-triphenylmethane triisocyanate, 2,4,6-toluene triisocyanates; the aromatic tetraisocyanates such as 4,4-dimethyldiphenylmethane-2,25,5-tetraisocyanate, and the like; arylalkyl polyisocyanates such as xylylene diisocyanate; aliphatic polyisocyanate such as hexamethylene-1,6-diisocyanate, lysine diisocyanate methylester and the like; and mixtures thereof. Other organic polyisocyanates include polymethylene polyphenylisocyanate, hydrogenated methylene diphenylisocyanate, m-phenylene diisocyanate, naphthylene-1,5-diisocyanate, 1-methoxyphenylene-2,4-diisocyanate, 4,4-biphenylene diisocyanate, 3,3-dimethoxy-4,4-biphenyl diisocyanate, 3,3-dimethyl-4,4-biphenyl diisocyanate, and 3,3-dimethyldiphenylmethane-4,4-diisocyanate; Typical aliphatic polyisocyanates are alkylene diisocyanates such as trimethylene diisocyanate, tetramethylene diisocyanate, and hexamethylene diisocyanate, isophorene diisocyanate, 4, 4-methylenebis(cyclohexyl isocyanate), and the like; typical aromatic polyisocyanates include m-, and p-phenylene disocyanate, polymethylene polyphenyl isocyanate, 2,4- and 2,6-toluenediisocyanate, dianisidine diisocyanate, bitoylene isocyanate, naphthylene 1,4-diisocyanate, bis(4-isocyanatophenyl)methene, bis(2-methyl-4-isocyanatophenyl)methane, and the like. Preferred polyisocyanates are the polymethylene polyphenyl isocyanates, Particularly the mixtures containing from about 30 to about 85 percent by weight of methylenebis(phenyl isocyanate) with the remainder of the mixture comprising the polymethylene polyphenyl polyisocyanates of functionality higher than 2. These polyisocyanates are prepared by conventional methods known in the art. In the present invention, the polyisocyanate and the polyol are employed in amounts which will yield an NCO/OH stoichiometric ratio in a range of from about 0.9 to about 5.0. In the present invention, the NCO/OH equivalent ratio is, preferably, about 1.0 or more and about 3.0 or less, with the ideal range being from about 1.1 to about 2.5. Especially suitable organic polyisocyanate include polymethylene polyphenyl isocyanate, methylenebis(phenyl isocyanate), toluene diisocyanates, or combinations thereof.

[0040] In the preparation of polyisocyanurate foams, trimerization catalysts are used for the purpose of converting the blends in conjunction with excess A component to polyisocyanurate-polyurethane foams. The trimerization catalysts employed can be any catalyst known to one skilled in the art, including, but not limited to, glycine salts, tertiary amine trimerization catalysts, quaternary ammonium carboxylates, and alkali metal carboxylic acid salts and mixtures of the various types of catalysts. Preferred species within the classes are potassium acetate, potassium octoate, and N-(2-hydroxy-5-nonylphenol)methyl-N-methylglycinate.

[0041] Conventional flame retardants can also be incorporated, preferably in amount of not more than about 20 percent by weight of the reactants. Optional flame retardants include tris(2-chloroethyl)phosphate, tris(2-chloropropyl)phosphate, tris(2,3-dibromopropyl)phosphate, tris(1,3-dichloropropyl)phosphate, tri(2-chloroisopropyl)phosphate, tricresyl phosphate, tri(2,2-dichloroisopropyl)phosphate, diethyl N,N-bis(2-hydroxyethyl) aminomethylphosphonate, dimethyl methylphosphonate, tri(2,3-dibromopropyl)phosphate, tri(1,3-dichloropropyl)phosphate, and tetra-kis-(2-chloroethyl)ethylene diphosphate, triethylphosphate, diammonium phosphate, various halogenated aromatic compounds, antimony oxide, aluminum trihydrate, polyvinyl chloride, melamine, and the like. Other optional ingredients can include from 0 to about 7 percent water, which chemically reacts with the isocyanate to produce carbon dioxide. This carbon dioxide acts as an auxiliary blowing agent. In the case of this invention, the water cannot be added to the polyol blend but, if used, can be added as a separate chemical stream. Formic acid is also used to produce carbon dioxide by reacting with the isocyanate and is optionally added to the B component.

[0042] In addition to the previously described ingredients, other ingredients such as, dyes, fillers, pigments and the like can be included in the preparation of the foams. Dispersing agents and cell stabilizers can be incorporated into the present blends. Conventional fillers for use herein include, for example, aluminum silicate, calcium silicate, magnesium silicate, calcium carbonate, barium sulfate, calcium sulfate, glass fibers, carbon black and silica. The filler, if used, is normally present in an amount by weight ranging from about 5 parts to 100 parts per 100 parts of polyol. A pigment which can be used herein can be any conventional pigment such as titanium dioxide, zinc oxide, iron oxide, antimony oxide, chrome green, chrome yellow, iron blue siennas, molybdate oranges and organic pigments such as para reds, benzidine yellow, toluidine red, toners and phthalocyanines.

[0043] The polyurethane or polyisocyanurate foams produced can vary in density from about 0.5 pounds per cubic foot to about 60 pounds per cubic foot, preferably from about 1.0 to 20.0 pounds per cubic foot, and most preferably from about 1.5 to 6.0 pounds per cubic foot. The density obtained is a function of how much of the blowing agent or blowing agent mixture disclosed in this invention plus the amount of auxiliary blowing agent, such as water or other co-blowing agents is present in the A and/or B components, or alternatively added at the time the foam is prepared. These foams can be rigid, flexible, or semi-rigid foams, and can have a closed cell structure, an open cell structure or a mixture of open and closed cells. These foams are used in a variety of well known applications, including but not limited to thermal insulation, cushioning, flotation, packaging, adhesives, void filling, crafts and decorative, and shock absorption.

[0044] The following non-limiting examples serve to illustrate the invention.

Example 1 (Comparative Example)

[0045] A polyol (B Component) formulation was made up of 100 parts by weight of a polyol blend, 1.5 parts by weight Niax L6900 silicone surfactant, 1.5 parts by weight water, 4.0 parts by weight N,N-dicyclohexylmethylamine (sold as Polycat 12 by Air Products and Chemicals) catalyst, and 8 parts by weight trans-1,3,3,3-tetrafluoropropene blowing agent. The total B component composition, when freshly prepared and combined with 120.0 parts by weight of Lupranate M20S polymeric isocyanate yielded a good quality foam with a fine and regular cell structure. Foam reactivity was typical for a pour in place foam. The total B-side composition (115.0 parts) was then aged at 130 F. for 336 hours, and then combined with 120.0 parts of M20S polymeric isocyanate to make a foam. The foam was very poor in appearance with significant cell collapse. Significant yellowing of the polyol premix was noted during aging.

Example 2 (Foam Test)

[0046] A polyol (B Component) formulation was made up of 100 parts by weight of a polyol blend, 1.5 parts by weight Niax L6900 silicone surfactant, 0.0 parts by weight water, 2.0 parts by weight N,N-dicyclohexylmethylamine (sold as Polycat 12 by Air Products and Chemicals) catalyst, and 8 parts by weight trans-1,3,3,3-tetrafluoropropene blowing agent. The total B component composition, when freshly prepared and combined with 120.0 parts by weight of Lupranate M20S polymeric isocyanate yielded a good quality foam with a fine and regular cell structure. Foam reactivity was typical for a pour in place foam. The total B-side composition (114.75 parts) was then aged at 130 F. for 336 hours, and then combined with 120.0 parts of M20S polymeric isocyanate to make a foam. The foam was excellent in appearance with no evidence of cell collapse. There was only slight yellowing of the polyol premix noted during aging. The foam exhibited acceptable k-values. As used herein, k-value is defined as the rate of transfer of heat energy by conduction through one square foot of one-inch thick homogenous material in one hour where there is a difference of one degree Fahrenheit perpendicularly across the two surfaces of the material.

Example 3 (Comparative Example)

[0047] A polyol (B Component) formulation was made up of 100 parts by weight of a polyol blend, 1.5 parts by weight Niax L6900 silicone surfactant, 1.5 parts by weight water, 1.2 parts by weight N,N,N,N,N,N-pentamethyldiethyltriamine (sold as Polycat 5 by Air Products and Chemicals) catalyst, and 8 parts by weight trans-1-chloro-3,3,3-tetrafluoropropene blowing agent. The total B component composition, when freshly prepared and combined with 120.0 parts by weight of Lupranate M20S polymeric isocyanate yielded a good quality foam with a fine and regular cell structure. Foam reactivity was typical for a pour in place foam. The total B-side composition (115.0 parts) was then aged at 130 F. for 336 hours, and then combined with 120.0 parts of M20S polymeric isocyanate to make a foam. The foam was very poor in appearance with almost 100% cell collapse. Significant yellowing of the polyol premix was noted during aging.

Example 4 (Foam Test)

[0048] A polyol (B Component) formulation was made up of 100 parts by weight of a polyol blend, 1.5 parts by weight Niax L6900 silicone surfactant, 0.0 parts by weight water, 1.2 parts by weight N,N,N,N,N,N-pentamethyldiethyltriamine (sold as Polycat 5 by Air Products and Chemicals) catalyst, and 8 parts by weight trans-1,3,3,3-tetrafluoropropene blowing agent. The total B component composition, when freshly prepared and combined with 120.0 parts by weight of Lupranate M20S polymeric isocyanate yielded a good quality foam with a fine and regular cell structure. Foam reactivity was typical for a pour in place foam. The total B-side composition (114.75 parts) was then aged at 130 F. for 336 hours, and then combined with 120.0 parts of M20S polymeric isocyanate to make a foam. The foam was excellent in appearance with only moderate evidence of cell collapse. There was only slight yellowing of the polyol premix noted during aging.