Hindered Ether Amine Polyurethane Catalyst

Abstract

A polyol resin blend suitable for rigid foam applications, comprising one or more active hydroxyl compounds, a silicone surfactant, a halogenated olefin blowing agent, and an amine catalyst. The polyol resin blend may include from about 0.3% to about 7% by weight of the amine catalyst. The polyol resin blend may be used to form polyurethane and / or polyisocyanurate foams.

Description

[Technical field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims priority to U.S. Provisional Application No. 63 / 244,972, filed September 16, 2021, and U.S. Provisional Application No. 63 / 351,091, filed June 10, 2022. The applications referenced are incorporated herein by reference.

[0002] Technical Field The present disclosure relates generally to catalysts for use in producing thermoset polyurethane and / or polyisocyanurate foams. More particularly, the present disclosure relates to polyurethane catalysts having ether groups and sterically hindered amine groups. [Background technology]

[0003] Thermosetting foams may have utility in a wide variety of material applications, including, but not limited to, thermal insulation. Such foams can be produced by mixing a polyisocyanate with a polyol resin blend that includes at least a combination of a blowing agent, a polyol, and an amine catalyst. To produce an industrially viable foam, the polyol resin blend must impart sufficient strength to the foam and allow the foam to form quickly enough to maintain the desired cell structure. For example, if the composition does not impart or does not impart sufficient strength quickly enough, the foam may collapse during formation or lack physical strength in its finished form, making the finished foam unsuitable. The composition of the polyol resin blend can be adjusted to achieve the properties desired for the resulting foam.

[0004] In recent years, new blowing agents that have little or no impact on ozone depletion or global warming, in contrast to the previous generation blowing agents chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons (HCFCs), have been introduced into the polyurethane and / or polyisocyanurate foam market. These blowing agents, known as halogenated olefin blowing agents, hydrofluoroolefins (HFOs) or hydrochlorofluoroolefins (HCFOs), have been widely adopted in spray thermoset foams. The performance of spray thermoset foams depends on the exothermic reaction between polyisocyanates and water-containing polyol resin blends, which releases heat and carbon dioxide (CO2) to cause the blowing agent to boil, and simultaneously results in rapid polymerization and cell structure formation. Metal and amine catalysts can accelerate this reaction to acceptable rates, which is a necessary part of any spray thermoset foam formulation.

[0005] Conventional spray thermoset foam amine catalysts have multiple methylamine groups which minimize steric hindrance around the amine groups, allowing for faster catalysis of the polyurethane and / or polyisocyanurate foam forming reaction while minimizing catalyst loading. The structures of some common spray thermoset foam catalysts are provided below: [ka]

[0006] However, the use of such amine catalysts in HFO-containing polyol resins can cause undesirable reactions between the amines, blowing agents, and surfactants, resulting in the degradation or failure of the polyol resin blend. Undesirable reactions can cause, but are not limited to, the release of chlorine and / or fluorine ions. Such reactions can reduce the activity of the catalysts present and can destroy the blowing agents. Also, the fluorine ions detached from the HFO molecules attack the silicon element of the silicone surfactant, decomposing the surfactant, which reduces the surfactant performance and weakens the cell structure of the resulting foam. The combination of the above reactions can result in an unstable polyol system, and if a foam is sprayed using an unstable system, the foam may not rise properly and may have an irregular and inconsistent cell structure.

[0007] Regardless of the current state of the art, there is a continuing need to develop amine catalysts that are capable of promoting rapid reaction of isocyanate and polyol resin blends, but that do not significantly affect the storage stability of the blends when HFO blowing agents are used. [Brief description of the drawings]

[0008] The features of the present disclosure can be understood in more detail in the more particular description of the invention and can be learned by reference to embodiments, some of which are illustrated in the accompanying drawings. It should be noted, however, that the accompanying drawings illustrate only typical embodiments of the present disclosure and therefore should not be construed as limiting the scope thereof, as the present disclosure may admit of other equally effective embodiments. [Figure 1] 1 is a graph showing the stability over time of an amine catalyst according to the present disclosure. [Diagram 2] 1 is a graph showing rise rate curves illustrating cream time and catalyst rate measurements. [Diagram 3] 1 is a graph showing drift, cure speed, and cream time for various catalysts. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Before describing aspects of the present disclosure in detail, it is to be understood that the present disclosure is not limited in its application to the details of the construction and arrangement of the elements or steps or methods set forth in the following description. The present disclosure is capable of other embodiments or of being practiced or carried out in various ways. It is also to be understood that the phraseology and terminology used herein are for the purpose of description and should not be regarded as limiting.

[0010] Unless otherwise defined herein, technical terms used in connection with the present disclosure shall have the meanings that are commonly interpreted by those of ordinary skill in the art. Further, unless otherwise required by context, singular terms shall include pluralities and plural terms shall include the singular.

[0011] All patents, published patent applications, and non-patent publications mentioned in this specification are indicative of the level of skill of those skilled in the art to which this disclosure pertains. All patents, published patent applications, and non-patent publications referenced anywhere in this application are expressly incorporated by reference in their entirety herein to the same extent as if each individual patent or publication was specifically and individually indicated to be incorporated by reference unless inconsistent with this disclosure.

[0012] All of the compositions and / or methods disclosed herein can be made and executed without undue experimentation in light of the present disclosure. Although the compositions and methods of the present disclosure have been described in terms of preferred embodiments, it will be apparent to those skilled in the art that modifications can be applied to the compositions and / or methods described herein, and to the steps or sequence of steps of the methods, without departing from the concept, spirit, and scope of the present disclosure. All such similar substitutes and modifications apparent to those skilled in the art are deemed to be within the concept, spirit, and scope of the present disclosure.

[0013] As used in accordance with the present disclosure, the following terms, unless otherwise indicated, shall be understood to have the following meanings:

[0014] The use of the words "a" or "an," when used in conjunction with the terms "comprising," "including," "having," or "containing" (or variations of such terms), can mean "one," but is not inconsistent with the meanings of "one or more," "at least one," and "one or more than one."

[0015] Use of the term "or" is used to mean "and / or," unless expressly stated to refer only to alternatives and only where the alternatives are mutually exclusive.

[0016] Whenever "may," "can," "could," or "might" is used in this specification to describe that a certain element or feature is included or has a certain characteristic, it does not require that the particular element or feature be included or have the certain characteristic.

[0017] Throughout this disclosure, the term "about" is used to indicate that a value includes the inherent variation of error of a quantitative device, mechanism, or method, or includes the inherent variation that exists among the subject(s) being measured. By way of example, and not limitation, when the term "about" is used, the specified value to which it refers can vary by plus or minus 10%, or 9%, or 8%, or 7%, or 6%, or 5%, or 4%, or 3%, or 2%, or 1%, or one or more fractions therebetween.

[0018] The use of "at least one" is to be interpreted as including one as well as any amount greater than one, including, but not limited to, 1, 2, 3, 4, 5, 10, 15, 20, 30, 40, 50, 100, etc. The term "at least one" can extend up to 100 or up to 1000 or more, depending on the term to which it refers. Also, the amount 100 / 1000 should not be interpreted as a limit, since a lower or higher limit can also yield satisfactory results.

[0019] Additionally, the phrase "at least one of X, Y, and Z" shall be interpreted to include X alone, Y alone, and Z alone, as well as any combination of X, Y, and Z. Similarly, the phrase "at least one of X and Y" shall be interpreted to include X alone, Y alone, and any combination of X and Y. It should also be understood that the phrase "at least one of" may be used with any number of elements and has the same meaning as set forth above.

[0020] As used herein, the words "comprising" (and any form thereof, e.g., "comprise" and "comprises"), "having" (and any form thereof, e.g., "have" and "has"), "including" (and any form thereof, e.g., "includes" and "include"), or "containing" (and any form thereof, e.g., "contains" and "contain") are inclusive or open-ended and do not exclude additional, unrecited elements or method steps.

[0021] Phrases such as "in one embodiment," "in an embodiment," "according to one embodiment," and the like generally mean that the particular feature, structure, or characteristic that follows the phrase is included in at least one embodiment of the disclosure, and may be included in more than one embodiment of the disclosure. Importantly, such phrases are open-ended and do not necessarily refer to the same embodiment, but rather, of course, can refer to one or more prior and / or subsequent embodiments. For example, in the appended claims, any of the claimed embodiments can be used in any combination.

[0022] As used herein, the terms "weight %", "wt%", "weight percentage", or "percentage by weight" are used interchangeably.

[0023] The early stage "blowing" reaction between isocyanate and water is accelerated by certain polyurethane catalysts and is crucial to producing a viable spray foam system. Surprisingly, it has been discovered that a narrow range of amine catalysts produces stable and strong spray thermoset foams when used with hydrofluoroolefin (HFO)-containing polyol resin blends. In at least one example, the polyol resin blends described herein can include one or more active hydroxyl compounds, silicone surfactants, halogenated olefin blowing agents, and amine catalysts. The polyol resin blends can be used to produce spray thermoset foams by combining isocyanates with the polyol resin blends.

[0024] Many amine catalysts and amine catalyst formulations can be used in HFO-containing polyol resin blends, but few are industrially useful. Various problems can arise, including but not limited to an imbalance between catalyst stability and catalyst speed. For example, catalysts that are generally more stable with HFO blowing agents are typically not fast enough to produce foams that do not collapse or drip, or the amounts of them required for the system are not economically viable. Similarly, catalysts that are fast enough to produce viable spray thermoset foams are generally not stable enough to be used in HFO-containing polyol resin blends. For example, dimorpholinodiethylether (DMDEE, also known as JEFFCAT® DMDEE, sold by Huntsman) catalysts can be very stable in the presence of HFO blowing agents (as described in U.S. Patent Publication Nos. 2020 / 012650 and 2012 / 0313035). However, due to the structure of the compound, DMDEE is not a fast enough catalyst to be used as the primary catalyst for sprayed thermoset foam systems. Other standard spray foam catalysts, including but not limited to JEFFCAT® ZF-20, JEFFCAT® PMDETA, JEFFCAT® ZF-10, JEFFCAT® Z-130, JEFFCAT® Z-110, and JEFFCAT® ZR-70, have traditionally been used in spray thermoset foams because they are fast enough catalysts, but are very unstable when placed in polyol resin blends with HFO blowing agents and can spoil the formulation within a few weeks of storage time.

[0025] Imidazole compounds are known to be stable when used in polyol resin blends with HFO blowing agents (as described in US Patent Publication Nos. 2016 / 0130416, 9,556,303, and WO 2020146442), but are strongly biased toward the gel reaction and the early stages of the spray thermoset foam reaction. In an alternative resin blend, the catalyst can be pre-reacted with an acid known to improve the stability of HFO systems by "blocking" the amine during storage, and the exotherm of the spray thermoset foam reaction can be allowed by "unblocking" the amine (as described in US Patent Publication Nos. 9,453,115, 10,023,681, 10,066,071, 2020 / 0255581, and 2019 / 0062515). However, the introduction of acids into polyol resin blends can increase the occurrence of negative side effects, including but not limited to slowing down other catalysts, decreasing cream time, increasing catalyst loading requirements, and increasing the corrosiveness of the blends, which can damage metal parts of spray thermoset foam equipment. Due to the increased side effects, acid blocking additives are generally avoided in spray thermoset foam formulations.

[0026] In other applications, fast cream time may not be as critical, but is still desirable. In such cases, an acid-blocked foaming amine can be used to enhance resin stability in the HFO system. The present disclosure provides a polyol resin blend (also referred to herein as the "B-side"), which comprises a polyol resin blend having (a) a sterically hindered amine catalyst and (b) an amine of the formula (OH) a -R-(COOH) b and a compound having the formula (OH) where R is selected from hydrogen, an alkyl group, an alkenyl group, an alicyclic group, an aromatic group, and an alkyl aromatic group, and a and b are integers from 0 to 3, with the proviso that a+b≧1, and when a=1 and b=0, R is selected from an aromatic group and an alkyl aromatic group. a -R-(COOH)b The compound having the formula (I) can have 1-12 carbon atoms and can be a carboxylic acid, dicarboxylic acid, tricarboxylic acid, phenolic acid, substituted phenolic acid, or hydroxy-substituted derivatives thereof. Examples of R alkyl groups can include, but are not limited to, methyl, ethyl, n-propyl, isopropyl, propyl, butyl, isobutyl, phenyl, ethylenyl, n-amyl, n-decyl, or 2-ethylhexyl groups. Although the above alkyl groups can have two available substitution sites, it is contemplated that additional hydrogens on the hydrocarbon can be further substituted with carboxyl and / or hydroxyl groups. In at least one example, (OH) a -R-(COOH) b Compounds having the formula (I) may include, but are not limited to, hydroxyl-carboxylic acids, adipic acid, glutaric acid, succinic acid, formic acid, acetic acid, malonic acid, maleic acid, glycolic acid, lactic acid, 2-hydroxybutyric acid, citric acid, polyacrylic acid, adipic-glutaric-succinic (AGS) acid, phenol, cresol, hydroquinone, or combinations thereof. AGS is a mixture of dicarboxylic acids (i.e., adipic acid, glutaric acid, and succinic acid), which can be obtained as a by-product of cyclohexanol and / or cyclohexanone oxidation in the adipic acid manufacturing process. Suitable AGS acids that can be used include RHODIACID® acid (available from Solvay SA), dibasic acid (available from Invista Sarl), FLEXATRAC™-AGS-200 acid (available from Ascend Performance Materials LLC), and glutaric acid, technical grade (AGS) (available from Lanxess AG).

[0027] Alternatively, sterically hindered catalysts have been used to improve the stability of HFO systems. Analysis shows that the more bulky the alkyl groups added around the amine, the slower the reactive decomposition of the HFO molecule appears to be, thereby improving the stability of the system. For example, in U.S. Patent No. 9,550,854, it is disclosed that the use of hindered catalysts such as, but not limited to, dicyclohexylmethylamine, diisopropylethylamine, and dicyclohexylamine greatly reduces the decomposition of HFO blowing agents. However, the catalysts highlighted in this study were only determined to be suitable for pour-in-place foams because they provided gel times of less than about 100 seconds. Therefore, these catalysts are not suitable for spray foams due to their slow reactivity. Dicyclohexylmethylamine has been used as a hindered catalyst in HFO systems (US Patent Publication Nos. 2017 / 0066867 and 2019 / 0092920), but no evidence was provided that such catalysts could provide sufficient cream time for use in spray foam systems. In fact, US Patent Publication No. 2019 / 0136005 indicates that when slow hindered amines are used as catalysts, high levels of metal catalysts (including but not limited to tin, bismuth, lead, zinc) must be used to compensate for the slow reactivity of the amines.

[0028] All amine catalysts will accelerate this "blowing" reaction to some degree, but certain molecular structures are known to provide the fastest and most selective catalysis. Specifically, catalysts with tertiary amines attached to an ether group with two carbons, as shown below, are excellent at catalyzing the blowing reaction. [ka] Examples of commercially available catalysts in this category include, but are not limited to, JEFFCAT® ZF-20, JEFFCAT® ZF-10, JEFFCAT® LE-30, and JEFFCAT® ZR-70. In particular, catalysts having a bisaminoethyl ether (BAEE) moiety, such as JEFFCAT® ZF-20, can be very powerful blowing catalysts, likely due to the ability of the compounds to complex with water molecules and activate them for reaction with isocyanates, as shown in the following structure: [ka]

[0029] However, commercially available catalysts with BAEE moieties are unstable when used in HFO systems due to the strong nucleophilicity of the amines. Some BAEE moiety-containing amines have been analyzed. Specifically, U.S. Patent Publication No. 2019 / 0315905 describes amines of the general formula R1R2N-[A-NR3] n It describes the use of sterically hindered amines bearing R4 in conjunction with HFO blowing agents, where R1-R4 can include (among other things) alkyl groups, A is (among other things) an ether group, and n is 0 to 3. However, only a very small subset of the disclosed structures have actually been made and tested, and none of them have provided fast reactivity in sprayed foam systems.

[0030] Several HFO-stable formulations have been described (US Pat. No. 10,308,783). They are made with antioxidants and catalysts having the general formula R1R2N(CH2)2X, where R1 and R2 are the same or different and are each selected from a C1-C6 alkyl group and / or an alkanol group; X is O(CH2)2Y, OH, or NR3(CH2)2Y, where R3 is a C1-C6 alkyl group or an alkanol group, and Y is OH or NR4R5, where R4 and R5 are the same or different and are each a C1-C6 alkyl group or an alkanol group, provided that the compounds contain at least one ether and / or hydroxyl group. However, the structures described represent a very large set of compounds, only a small portion of which has been exemplified and / or tested. Of the compounds tested, a significant shift in reactivity was observed only after 7 days, making these systems industrially useless. This work did not synthesize or test any products with alkylamino groups larger than C1.

[0031] Finally, a catalyst composition is described (WO 2020174030) having the following structure: [ka] where A is O, X is 0-6, n and m are each independently 1-6, R1 and R2 are each independently C2-C8 alkyl, and R4 and R5 are -CH3 groups. Many possible compounds described by this general structure have been considered for application in polyurethane formulations containing HFO blowing agents, but none have been synthesized in a corresponding formulation, exemplified, or tested in an HFO formulation.

[0032] As shown, although various Markush structures have been disclosed in the prior art, no examples of such structures have been synthesized or tested that (a) have a BAEE structure, (b) are fast enough to be a spray foam catalyst, and (c) are stable with HFO blowing agents. There are a great number of possible compounds encompassed by these Markush structures, and it is not obvious to one skilled in the art which catalyst will provide an industrially useful balance of catalytic speed and HFO stability. Surprisingly, it has been found that an amine catalyst having the following structure provides an industrially viable spray foam. [ka] In at least one example, amines in which R1 is an ethyl, isopentane, isopropyl, or isobutyl group, R2 is a methyl, ethyl, or isopropyl group, and n is selected from 1, 2, or 3 in the above structure can produce strong and stable foams. Such catalysts have been determined to produce effective spray thermoset foams when used in amounts of about 0.1% to about 10% by weight of the total weight of the polyol resin blend. In a further example, the catalyst loading can be about 0.3% to about 7% by weight based on the total weight of the polyol resin blend. In yet another example, the catalyst loading can be about 0.5% to about 5% by weight based on the total weight of the polyol resin blend.

[0033] In some cases, the amine catalyst can be a combination of two or more of the catalysts disclosed herein. For example, the amine catalyst can include a combination of an imidazole catalyst and a sterically hindered amine catalyst, such as a catalyst having the following structure: [ka] In at least one embodiment, the amine catalyst can comprise a mixture of about 10% to about 80% by weight of the imidazole catalyst and about 20% to about 90% by weight of the catalyst having the above structure, where the weight percent is based on the total weight of the mixture, and the sum of the amount of the imidazole catalyst plus the amount of the catalyst having the above structure equals 100%. In an alternative embodiment, the amine catalyst can comprise a mixture of about 10% to about 70% by weight of the imidazole catalyst and about 30% to about 90% by weight of the catalyst having the above structure, or the amine catalyst can comprise a mixture of about 10% to about 60% by weight of the imidazole and about 40% to about 90% by weight of the catalyst having the above structure, where the weight percent is based on the total weight of the mixture, and the sum of the amount of the imidazole catalyst plus the amount of the catalyst having the above structure equals 100%.

[0034] A large number of etheramine and BAEE-based compounds have been synthesized and tested, and surprisingly, only a narrow and non-obvious subset of these compounds have been shown to have an industrially useful balance of catalytic speed, cream time, and HFO stability. Examples of the synthesis reactions of the present invention are presented below. However, it should be understood that the present disclosure is not limited in its application to the specific experiments, results, and experimental procedures disclosed herein below. Instead, the examples are provided simply as one of various embodiments and are meant to be illustrative and not exclusive. EXAMPLES

[0035] Example 1: Synthesis of N,N-isopropylmethylethanolamine In a reaction vessel, 100 grams of N-isopropylethanolamine was mixed with a slight molar excess of formic acid and formaldehyde and heated to a temperature of 80° C. During the reaction, CO gas was evolved as is typical for the Eschweiler / Clarke methylation reaction. The resulting mixture was neutralized with aqueous sodium hydroxide and the amine was distilled under reduced pressure (boiling point 69° C. at 22 mmHg) to provide N,N-isopropylmethylethanolamine in greater than 99% purity as compound (I) of the following structure: [ka]

[0036] Example 2: Synthesis of 2-(2-(isopropyl(methyl)amino)ethoxy)ethan-1-ol In a reaction vessel, diglycolamine (DGA) was dissolved in a minimum amount of methanol and co-fed with equimolar amounts of acetone and hydrogen gas to a continuous high pressure hydrogenation reactor at 150-190°C and 2000 psig. Palladium on carbon (Pd / C) catalyst was used for reduction. The resulting product was then fed through the same vessel, this time with a molar excess of formaldehyde and hydrogen gas at 100-140°C and 2000 psig over a supported polymetallic catalyst. The crude material was vacuum distilled to give the following product, compound (II), in greater than 99% purity: [ka]

[0037] Example 3: Synthesis of 2-((2-(isopropyl(methyl)amino)ethoxy)ethyl(methyl)amino)ethan-1-ol and 2-(isopropyl(2-(2-(isopropyl(methyl)amino)ethoxy)ethyl)amino)ethan-1-ol In a reaction vessel, 2-((2-(2-aminoethoxy)ethyl)amino)ethan-1-ol was dissolved in a minimum amount of methanol and co-fed with 1 mole of acetone per mole of amine group and hydrogen gas at 150-190° C. and 2000 psig pressure to a continuous high pressure hydrogenation reactor. Pd / C catalyst was used for reduction. The resulting product was then fed through the same vessel over a supported polymetallic catalyst at 100-140° C. and 2000 psig with a molar excess of formaldehyde and hydrogen gas. The resulting crude product was distilled to give the following compounds (III) and (IV) as two major fractions: [ka] [ka]

[0038] Example 4: Synthesis of N,N'-diisopropyl-N,N'-dimethyl-bis(aminoethyl) ether and N,N,N'-triisopropyl-N-methyl-bis(aminoethyl) ether In a reaction vessel, bis(aminoethyl)ether (BAEE) was dissolved in a minimum amount of methanol and co-fed with 1.3 moles of acetone per amine group and hydrogen gas to a continuous high pressure hydrogenation reactor at 150-190°C and 2000 psig. Pd / C catalyst was used for reduction. The resulting product was then fed back to the same vessel, this time over a supported polymetallic catalyst at 100-140°C and 2000 psig, along with excess formaldehyde and hydrogen gas. The resulting crude mixture was distilled to give the following two products, compounds (V) and (VI), in greater than 99% purity. [ka] [ka]

[0039] Example 5: Synthesis of 2-((2-(isopropyl(methyl)amino)ethyl)(methyl)amino)ethan-1-ol In a reaction vessel, aminoethylethanolamine (AEEA) was dissolved in a minimum amount of methanol and co-fed to a continuous high pressure hydrogenation reactor of methanol with 0.6 moles of acetone per amine group and hydrogen gas at 150-190°C and 2000 psig pressure. Pd / C catalyst was used for reduction. The resulting product was fed back to the same vessel, this time over a supported polymetallic catalyst at 100-140°C and 2000 psig with excess formaldehyde and hydrogen gas. The crude mixture was then distilled to obtain the following product of compound (VII) in greater than 99% purity: [ka]

[0040] Example 6: Synthesis of N-methyl-2-morpholino-N-(2-morpholinoethyl)ethan-1-ol In the reaction vessel, hydroxyethylmorpholine was fed to a continuous high pressure hydrogenation reactor and reductively aminated with a mixture of ammonia (15-30 fold molar excess) and hydrogen (10 fold molar excess) over a supported polymetallic catalyst at 150-200°C and 2000 psig pressure. The resulting product was vacuum distilled to remove the light materials and the remaining heavies were fed back to the same vessel, this time with excess formaldehyde and hydrogen gas, over the supported polymetallic catalyst at 100-140°C and 2000 psig. The crude mixture was then distilled to give the following product, compound (VIII), in greater than 99% purity: [ka]

[0041] Example 7: Synthesis of N,N'-((ethane-1,2-diylbis(oxy))bis(ethane-2,1-diyl))bis(N-methylpropan-2-amine) In a reaction vessel, 2,2'-(ethane-1,2-diylbis(oxy))bis(ethan-1-amine) was dissolved in a minimum amount of methanol and co-fed with 1.3 moles of acetone per amine group and hydrogen gas to a high pressure hydrogenation reactor at 150-190°C and 2000 psig pressure. Pd / C catalyst was used for reduction. The resulting product was fed back to the same vessel over a supported polymetallic catalyst at 100-140°C and 2000 psig with excess formaldehyde and hydrogen gas. The resulting crude mixture was distilled to give compound XVI, shown below, in about 99% purity. [ka]

[0042] Example 8: Synthesis of N,N'-(oxybis(ethane-2,1-diyl))bis(N-methylbutan-2-amine) In a reaction vessel, BAEE was dissolved in a minimum amount of methanol and co-fed with 1.3 moles per amine group of methyl ethyl ketone (MEK) and hydrogen gas to a high pressure hydrogenation reactor at 150-190°C and 2000 psig. Pd / C catalyst was used for reduction. The resulting product was fed back to the same vessel, this time with excess formaldehyde and hydrogen gas at 100-140°C and 2000 psig over a supported polymetallic catalyst. The resulting crude mixture was distilled to give compound XVII, shown below, in greater than 99% purity. [ka]

[0043] Example 9: Synthesis of tetraethyl-bis-dimethylaminoethyl ether In a reaction vessel, BAEE was dissolved in a minimum amount of methanol and co-fed with excess acetaldehyde and hydrogen gas to a high pressure hydrogenation reactor at 150-190°C and 2000 psig pressure. Pd / C catalyst was used for reduction. The resulting crude mixture was distilled to give compound XVIII, shown below, in greater than 99% purity. [ka]

[0044] The stability of compound XVIII was followed over a period of several weeks and is shown in Table 1 and illustrated in FIG. [Table 1] As shown, the stability of the compound did not decrease significantly over a period of six weeks.

[0045] Example 10 In a reaction vessel, BAEE was dissolved in a minimum amount of methanol and co-fed with 1.2-3 moles of isobutyraldehyde per amine group and hydrogen gas to a high pressure hydrogenation reactor at 140-190°C and 2000 psig. Pd / C catalyst was used for reduction. The resulting product was fed back to the same vessel, this time with excess formaldehyde and hydrogen gas at 100-140°C and 2000 psig over a supported polymetallic catalyst. The resulting crude mixture was distilled to give the compounds shown below. [ka]

[0046] Comparative Example Other compounds were generated for comparison in HFO stability and foam reactivity testing, including the following compounds: [ka] [ka] [ka] [ka] [ka] [ka] [ka] Three factors were evaluated for the spray foam systems described herein using the catalysts described herein: stability, cream time, and catalyst rate. Stability was determined by storing systems containing the catalyst at a catalyst concentration of 5% for a period of six weeks at a temperature of 50°C. The reactivity of the systems was measured before and after the six week period and recorded as a percentage of the original gel time. The recorded information is used to quantify the stability of each system. Higher percentages (higher drift) are less effective than lower percentages. A useful system needs to have about 50% or less drift to be industrially viable. Cream time and catalyst rate were measured using an ultrasonic rate of rise measurement system. Polyol blends containing 1% of each catalyst were rapidly mixed with the isocyanate in a cup and placed under the device. Cream time was taken as the inflection point where the foam mixture began to rise. Catalyst "cure rate" was determined as the slope of the line during the linear portion of the foam growth curve. A slope of 5 mm / sec or greater is required for a catalyst to be industrially viable. This analysis is illustrated in FIG.

[0047] Cream time, catalyst rate, and catalyst stability data can be plotted as a "bubble" graph combining each of the data values ​​to show the most promising catalyst compounds. An exemplary bubble graph for the example catalysts above is presented in FIG. 3. As shown in the graph, the x-axis represents the catalyst stability as a drift in gel time. The larger the drift, the worse the catalyst stability in HFO systems. The y-axis represents the cure rate, which represents how fast the foam rises during its post-cream rise period. The bubble size represents the inverse of the cream time of the catalyst, and thus a larger bubble size indicates a faster cream time. To be industrially viable in HFO systems, a faster cream time indicates a more stable catalyst. A catalyst lacking any one of the categories would not be stable or strong enough to be used as a blowing catalyst in HFO systems. Comparative Examples X-XIII are not shown in the graph as the drift in stability was greater than 300%.

[0048] The most industrially viable catalysts are found in the upper left quadrant of the graph in FIG. 3, enclosed by dashed line A. Only two catalysts, compounds V and XVIII, are entirely within the industrially viable quadrant. As shown in the graph, compound V has the fastest cream time of this class of catalyst. The graph shows that, unexpectedly, compounds V and XVIII have a very good combination of speed, cream time, and stability. When reviewing only the isopropyl-modified compounds, compound V performs significantly better than the others, which is surprising considering how similar the structures are to each other. Several other examples with isopropyl / methyl combinations on the same nitrogen include compounds I, II, III, IV, VII, and XVI, but none of these compounds exhibited the very good properties of compound V. The unexpected properties exhibited by compound V when used in HFO systems were not obvious based on the prior art described herein. As clearly illustrated, catalysts of similar structure do not provide the same benefits.

[0049] From the foregoing description, it will be seen that the present disclosure is well adapted to carry out the objects and obtain the advantages mentioned herein as well as those inherent therein. While illustrative embodiments of the present disclosure have been described for purposes of disclosure, it will be appreciated that numerous modifications can be made which will be readily suggested to those skilled in the art and which can be effected without departing from the scope of the present disclosure and the appended claims.

Claims

1. 1. A polyol resin blend suitable for rigid foam applications, comprising one or more active hydroxyl compounds, a silicone surfactant, a halogenated olefin blowing agent, and an amine catalyst having the following structure: 【Chemical 1】 In the formula, R 1 is an ethyl, isopentane, isopropyl, or isobutyl group, and R 2 is a methyl, ethyl, or isopropyl group, and n=1, 2, or 3; The polyol resin blend comprising:

2. Furthermore, the formula (OH) a -R-(COOH) b wherein R is one of hydrogen, an alkyl group, an alkenyl group, an alicyclic group, an aromatic group, or an alkyl aromatic group; preferably R is a methyl, ethyl, n-propyl, isopropyl, propyl, butyl, isobutyl, phenyl, ethylenyl, n-amyl, n-decyl, or 2-ethylhexyl group; and a and b are integers from 0 to 3 with the proviso that a+b≧1, and when a=1 and b=0, R is selected from aromatic groups and alkyl aromatic groups.

3. 3. The polyol resin blend of claim 1 or 2, wherein n=1 or 2.

4. R 1 is an isopropyl or isobutyl group; and / or R 2 is a methyl group; or R 1 and R 2 are ethyl; The polyol resin blend according to claim 1 or 2.

5. 1. A polyurethane foam composition comprising an isocyanate and an HFO-containing polyol resin blend, wherein the HFO-containing polyol resin blend comprises a catalyst having the structure: 【Chemistry 2】 In the formula, R 1 is an ethyl, isopentane, isopropyl, or isobutyl group, and R 2 is a methyl, ethyl, or isopropyl group, and n=1, 2, or 3; The polyurethane foam composition comprising:

6. Furthermore, the formula (OH) a -R-(COOH) b wherein R is one of hydrogen, an alkyl group, an alkenyl group, an alicyclic group, an aromatic group, or an alkylaromatic group; preferably R is a methyl, ethyl, n-propyl, isopropyl, propyl, butyl, isobutyl, phenyl, ethylenyl, n-amyl, n-decyl, or 2-ethylhexyl group; and a and b are integers from 0 to 3 with the proviso that a+b≧1, and when a=1 and b=0, R is selected from aromatic groups and alkylaromatic groups.

7. 7. The polyurethane foam composition according to claim 5 or 6, wherein n=1 or 2.

8. R 1 is an isopropyl or isobutyl group; and / or R2 is a methyl group; The polyurethane foam composition according to claim 5 or 6.

9. A method for improving the stability and reactivity of HFO-containing polyol resin blends, comprising the step of: 【Chemistry 3】 In the formula, R 1 is an ethyl, isopentane, isopropyl, or isobutyl group, and R 2 is a methyl, ethyl, or isopropyl group, and n=1, 2, or 3; into said HFO-containing polyol resin blend in an amount of 0.3 to 7 wt %, based on the total weight of said HFO-containing polyol resin blend.

10. R 1 and R 2 The method of claim 9 , wherein is ethyl.

11. 11. The method of claim 9 or 10, wherein n=1.

12. 1. A polyurethane amine catalyst composition comprising: (a) 10 to 60 weight percent of an imidazole catalyst; and (b) 10 to 60 weight percent of a catalyst having the structure: 【Chemistry 4】 In the formula, R 1 is an ethyl, isopentane, isopropyl, or isobutyl group, and R 2 teeth, is a methyl, ethyl, or isopropyl group, and n=1, 2, or 3; wherein the weight percent is based on the total weight of the mixture, and the amount of the imidazole catalyst plus the amount of the catalyst having the above structure equals 100%.

13. 13. The polyurethane amine catalyst composition of claim 12, wherein n=1 or 2.

14. 3. A polyurethane foam comprising a foam obtained from the reaction of an isocyanate with the polyol resin blend of claim 1 or 2.

15. 13. A polyurethane foam comprising a foam obtained from the reaction of an isocyanate with the polyurethane amine catalyst of claim 12.

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