Low odor silicone polyether surfactants and their use in polyurethane compositions

Abstract

This disclosure relates to low-odor silicone polyether surfactants and their use in polyurethane compositions. This disclosure also provides a method for stabilizing an SPE surfactant formed by grafting a vinyl polyether onto a silicone backbone, which comprises pretreating the SPE surfactant with a basic compound having a pKb of 1.0 to 9.0. This disclosure also provides an SPE surfactant obtained by the described method and its use in polyurethane compositions.

Description

[Technical Field]

[0001] The present disclosure relates to silicone polyether (SPE) surfactants. More specifically, the present disclosure relates to low odor stable silicone polyether surfactants, their preparation, and their use in polyurethane compositions. [Background technology]

[0002] Over the years, molecules such as aldehydes and cyclic ethers have been identified as undesirable odorants in various polyurethane products, including compounded polyols and flexible polyurethane foams. Examples of cyclic ethers that may be present in polyurethane foams include trioxocane, 2-ethyl-4-methyl-1,3-dioxolane (2-EMD), and 2,4-dimethyl-1,3-dioxolane (2-DMD).

[0003] Analytical work carried out to identify the cause of musty odor in flexible polyurethane foam has demonstrated that trioxocane and its isomers are one of the root causes of the malodor (see, for example, SH Harris et al., "Characterization of Polyurethane Foam Odor Bodies", Polyurethanes World Congress 1987, Aachen, Germany, pages 848-851). This is surprising in view of the relatively high boiling point of trioxocane (220°C), which highlights the strong olfactory power associated with this type of molecule.

[0004] The problem of malodor in polyurethane foam has become an industrial challenge. Various solutions have been proposed, such as using reactive amine catalysts (see, for example, U.S. Patent No. 8,563,676 (B2)) or using compounding ingredients synthesized in a way that reduces the presence of volatile species (see, for example, China Patent Application Publication No. 111247188 (A)). However, the contribution of aldehydes and cyclic ethers to the overall odor of polyurethane products has not yet been fully understood. Although humans have some knowledge about how cyclic ethers are formed, their understanding is limited, especially for polyurethane systems, and therefore no effective solution has been proposed to address this issue.

[0005] Therefore, there remains a need for low odor polyurethane compositions. Summary of the Invention

[0006] In an aspect, the present disclosure provides a method for stabilizing an SPE surfactant formed by grafting a vinyl polyether onto a silicone backbone, comprising pretreating the SPE surfactant with a basic compound having a pKb of 1.0 to 9.0.

[0007] In a further aspect, the present disclosure provides a stabilized SPE surfactant obtainable by the methods described herein.

[0008] In a further aspect, the present disclosure provides a method for producing a medicament for a medicament comprising: (A) a polyol component comprising one or more polyols selected from the group consisting of polyester polyols, polyether polyols, and combinations thereof; (B) an isocyanate component comprising one or more isocyanate compounds; and Including, A polyurethane composition is provided, wherein the (A) polyol component and / or the (B) isocyanate component comprises a stabilized SPE surfactant obtained by the method for stabilizing an SPE surfactant described herein.

[0009] In a further aspect, the present disclosure provides polyurethane articles formed using the polyurethane compositions described herein.

[0010] In a further aspect, the present disclosure provides the use of a stabilized SPE surfactant as described herein in the manufacture of a polyurethane composition.

[0011] In a further aspect, the present disclosure provides the use of a stabilized SPE surfactant as described herein in the manufacture of a polyurethane product.

[0012] It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention, as claimed. DETAILED DESCRIPTION OF THE INVENTION

[0013] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Additionally, all publications, patent applications, patents, and other references mentioned herein are incorporated by reference.

[0014] As disclosed herein, "and / or" means "and, or alternatively." All ranges are inclusive of the endpoints unless otherwise indicated.

[0015] As disclosed herein, all percentages referred to herein are by weight and temperatures are in degrees Celsius unless otherwise specified.

[0016] A. Stabilization of SPE surfactants The problem of odor in polyurethane foams has long been an unsolved problem in the art, with very limited understanding of the causes.

[0017] After a lengthy root cause analysis, the present inventors have discovered that silicone polyether (SPE) type surfactants (also referred to herein as "SPE surfactants") are a significant contributing source of odorous components in polyurethane foams, particularly flexible polyurethane foams for furniture and bedding applications.

[0018] SPE surfactants are widely used as surfactants in flexible and rigid polyurethane foams. They are typically formed by grafting vinyl polyethers onto a silicone backbone. The inventors have found that the manufacture of SPE surfactants, which may involve the use of excess amounts of some materials (such as vinyl polyethers) to ensure completeness of the hydrosilylation reaction, can result in the resulting SPE surfactants containing unsaturated species that can decompose during storage to form aldehydes and cyclic ethers, which can cause odor problems in polyurethane foams. This means that the use of SPE surfactants can have varying effects on the final odor of polyurethane foams, depending on the amount of unsaturated species initially present in the SPE surfactant and the storage time and conditions of the SPE surfactant. This finding is surprising, since SPE surfactants are typically present in amounts of only about 1% in total flexible polyurethane formulations and were expected to have negligible impact on final foam odor. Contrary to previous understanding, the inventors have demonstrated that SPE surfactants, even when used at low levels, can cause the formation of significant amounts of odorous components in the final polyurethane foam.

[0019] In an aspect, the present disclosure provides a method for stabilizing an SPE surfactant formed by grafting a vinyl polyether onto a silicone backbone, comprising pretreating the SPE surfactant with a basic compound having a pKb of 1.0 to 9.0.

[0020] As used herein, "SPE surfactants" typically refer to silicone surfactants having a siloxane backbone and polyether pendant groups. SPE surfactants may be non-hydrolyzable or hydrolyzable. Non-hydrolyzable surfactants, in which polyether pendant groups are attached to the siloxane backbone by Si-C bonds, are generally believed to produce "tight" polyurethane foams with high efficacy but poor breathability. Hydrolyzable surfactants, in which polyether pendant groups are attached to the siloxane backbone by Si-bonds, are generally believed to produce polyurethane foams with low efficacy, good processing properties, and good breathability. In some embodiments, SPE surfactants can be obtained by reacting a hydrogen siloxane (e.g., an organohydrogen siloxane) with a polyether compound having aliphatic unsaturation in the presence of a hydrosilylation catalyst. Methods for preparing SPE surfactants are known in the art and can be found in extensive literature, for example, EP 1 081 182 (B1), the entire contents of which are incorporated herein by reference.

[0021] In some embodiments, pre-treating the SPE surfactant with a basic compound comprises combining (eg, mixing) the SPE surfactant with the basic compound.

[0022] In some embodiments, the amount of basic compound used to pretreat the SPE surfactant is between 0.01% and 15% by weight of the SPE surfactant. In some embodiments, the amount of basic compound used to pretreat the SPE surfactant is in a range obtained by combining any two of the following endpoints of the SPE surfactant: 0.01%, 0.05%, 0.1%, 0.5%, 0.8%, 1%, 1.5%, 2%, 2.5%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, and 15%. In exemplary embodiments, the amount of basic compound used to pretreat the SPE surfactant is between 0.05% and 15%, between 0.1% and 15%, between 0.01% and 14%, or between 0.05% and 14% by weight of the SPE surfactant.

[0023] In some embodiments, the basic compound is liquid at room temperature and has a melting point below 20°C.

[0024] In some embodiments, the basic compound has a pKb between 1.0 and 9.0. In some embodiments, the basic compound has a pKb within a range obtained by combining any two of the following endpoints: 1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 7.0, 8.0, and 9.0. In exemplary embodiments, the basic compound has a pKb between 2.0 and 9.0, 2.0 and 8.0, 2.0 and 6.0, 2.0 and 5.0, 2.5 and 5.0, 2.8 and 5.0, or 3.0 and 5.0.

[0025] In some embodiments, the basic compound comprises an amine.

[0026] As used herein, the term "amine" refers to a compound in which one or more hydrogen atoms of ammonia are replaced by a hydrocarbon residue, and the number of hydrocarbon residues may be 1, 2, or 3. The hydrocarbon residue may be part of a linear or branched aliphatic hydrocarbon structure, may be part of an aliphatic hydrocarbon structure in which a cyclic structure such as a 5-membered ring or a 6-membered ring is formed, or may be an aromatic hydrocarbon. Furthermore, halogens such as fluorine, chlorine, and bromine, and functional groups such as hydroxyl groups and nitrile groups may be bonded to these aliphatic hydrocarbon residues or aromatic hydrocarbon residues.

[0027] In some embodiments, the amine can be selected from the group consisting of primary amines, secondary amines, tertiary amines, and any mixture thereof. The term "primary amine" refers to an amine having an ammonia molecule in which only one of the hydrogen atoms in the ammonia molecule has been replaced. The term "secondary amine" refers to an amine having an ammonia molecule in which two of the hydrogen atoms in the ammonia molecule have been replaced. The term "tertiary amine" refers to an amine having an ammonia molecule in which three of the hydrogen atoms in the ammonia molecule have been replaced. In certain embodiments, the amine comprises a tertiary amine.

[0028] In some embodiments, the amine can be selected from amine additives (e.g., amine catalysts) used in polyurethane foam formulations. In some embodiments, the amine can be selected from primary amine catalysts, secondary amine catalysts, tertiary amine catalysts, or any mixture thereof. In some embodiments, the amine comprises a tertiary amine catalyst. Tertiary amine catalysts include organic compounds that contain at least one tertiary nitrogen atom and are capable of catalyzing the hydroxyl / isocyanate reaction between the polyol component and the isocyanate component. In some embodiments, the amine catalyst has zero or at most one hydroxyl group.

[0029] Exemplary amine additives include 1-butylamine, di-n-butylamine, triethylenediamine, trimethylamine, triethylamine, tripropylamine, tributylamine, triamylamine, pyridine, quinoline, piperazine, tetramethylbutanediamine, pentamethyldiethylenetriamine, N,N-dimethylethanolamine, N,N-dimethylbenzylamine, N,N-dimethylpiperazine, morpholine, N-ethylmorpholine, N-coco-morpholine, bis(dimethylaminoethyl)ether, N-methylmorpholine, N-methylpropanol ... Folin, N-ethylpiperidine, 2-methylpropanediamine, methyltriethylenediamine, 2,4,6-tridimethylamino-methyl)phenol, 1,3-bis-(dimethylamino)-2-propanol, N,N-dimethylcyclohexylamine, N-cetyl-N,N-dimethylamine, N,N,N',N'-tetramethylethylenediamine, N,N,N',N'-tetramethyl-1,4-butanediamine, N,N,N'-trimethyl-N'-hydroxyethyl bis(aminoethyl)ether, N,N-bis(3-dimethylamino) Propyl)N-isopropanolamine, (N,N-dimethyl)amino-ethoxyethanol, N,N,N',N'-tetramethylhexanediamine, 1,8-diazabicyclo-5,4,0-undecene-7,2,4,6-tris(dimethylaminomethyl)phenol, N,N-dimorpholinodiethyl ether, N-methylimidazole, dimethylaminopropyldipropanolamine, bis(dimethylaminopropyl)amino-2-propanol, tetramethylaminobis(propylamine), (dimethyl(aminoethoxyethyl) )((dimethylamine)ethyl)ether, tris(dimethylaminopropyl)amine, dicyclohexylmethylamine, bis(N,N-dimethyl-3-aminopropyl)amine, 1,2-ethylenepiperidine, methylhydroxyethylpiperazine, pentamethyldiethylenetriamine, 1,4-diazobicyclo-2,2,2-octane, dimethylalkylamines in which the alkyl group contains 4 to 18 carbon atoms, dimethylethanolamine (DMEA), tetramethyliminobispropylamine (e.g., Polycat 15), N,Examples of suitable amines include, but are not limited to, N-dimethylcyclohexylamine (DMCHA), tetraethylenediamine (e.g., Dabco / TEDA), 2-[2-(dimethylamino)ethoxy]ethanol (DMEE), and N,N-bis(3-dimethylaminopropyl)-N-isopropylamine (e.g., JEFFCAT ZR-50), and mixtures thereof.

[0030] As used herein, "pretreatment" or "pretreating" an SPE surfactant means that the SPE surfactant is treated prior to subsequent application (e.g., in a polyurethane composition). In some embodiments, the pretreatment or stabilization of the SPE surfactant with a basic compound as described herein occurs after the SPE surfactant is synthesized or prepared. In other words, the basic compound is added to the SPE surfactant after the synthesis or preparation of the SPE surfactant is complete. The use of one or more basic compounds typically used during the synthesis or preparation of SPE surfactants is not sufficient to qualify as pretreatment or stabilization as described herein. In some embodiments, the pretreatment or stabilization occurs after the preparation of the SPE surfactant is complete and before it is packaged or stored.

[0031] The inventors have found that by pre-treating SPE surfactants according to the present disclosure, the SPE surfactants can be stabilized and degradation of the SPE surfactants during storage can be minimized. In accelerated aging tests (to simulate long-term storage), much lower levels of cyclic ethers and aldehydes can be observed in SPE surfactants treated in this way.

[0032] B. Stabilizing SPE Surfactants In a further aspect, the present disclosure provides a stabilized SPE surfactant obtainable by the above method.

[0033] "Stabilized SPE surfactant" refers to an SPE surfactant that has been pretreated or stabilized with a basic compound, as described above. In some embodiments, the stabilized SPE surfactant comprises an SPE surfactant mixed with a basic compound. In some embodiments, the basic compound is mixed with the SPE surfactant after the synthesis or preparation of the SPE surfactant is complete.

[0034] In some embodiments, the amount of basic compound included in the stabilized SPE surfactant is between 0.01% and 15% by weight of the SPE surfactant. In some embodiments, the amount of basic compound used to pretreat the SPE surfactant is in a range obtained by combining any two of the following endpoints of the SPE surfactant: 0.01%, 0.05%, 0.1%, 0.5%, 0.8%, 1%, 1.5%, 2%, 2.5%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, and 15%. In exemplary embodiments, the amount of basic compound used to pretreat the SPE surfactant is between 0.05% and 15%, between 0.1% and 15%, between 0.01% and 14%, or between 0.05% and 14% by weight of the SPE surfactant.

[0035] In some embodiments, the stabilized SPE surfactant produces less odorous compounds (e.g., 30%, 40%, 50%, 60%, 70%, 80%, 90%, or 95% or more less) than an identical SPE surfactant that has not been stabilized according to the present disclosure after about 14 days of storage at 25° C. or after more than 5 days of accelerated aging at 80° C. The odorous compounds can be one or more selected from aldehydes (e.g., propionaldehyde), cyclic ethers (e.g., trioxocane, EMD, DMD), or mixtures thereof.

[0036] The SPE surfactant and basic compound of the stabilized SPE surfactant are as described above in the section "A. Stabilization of the SPE Surfactant."

[0037] C. Polyurethane Composition In a further aspect, the present disclosure provides a method for producing a medicament for a medicament comprising: (A) a polyol component comprising one or more polyols selected from the group consisting of polyester polyols, polyether polyols, and combinations thereof; (B) an isocyanate component comprising one or more isocyanate compounds; and Including, A polyurethane composition is provided, wherein the (A) polyol component and / or the (B) isocyanate component comprises a stabilized SPE surfactant obtained by the method for stabilizing an SPE surfactant described herein.

[0038] The polyurethane composition according to the present disclosure is a two-component composition comprising (A) a polyol component and (B) an isocyanate component. In some embodiments, the polyurethane composition is a polyurethane foam composition.

[0039] As used herein, the term "two-component" means that the polyurethane foam composition is provided in separate portions prior to use. Typically, compositions according to the present disclosure can include at least a first component (also referred to herein as the "polyol component," "polyol component (A)," or "OH component") containing one or more polyols selected from the group consisting of polyester polyols, polyether polyols, and combinations thereof, and a second component (also referred to herein as the "isocyanate component," "isocyanate component (B)," or "NCO component") containing one or more isocyanate compounds. The polyol component and the isocyanate component can be prepared, stored, transported, and provided separately and can be combined, for example, shortly before or immediately before application to a potted product. It is contemplated that contacting these two components initiates a curing reaction in which the polyol groups react with the isocyanate groups to form urethane bonds. The reactive polyurethane dispersion formed by contacting the two components can be referred to as a "reaction mixture" or a "curable mixture."

[0040] In some embodiments, the NCO / OH ratio of the isocyanate component to the polyol component in the polyurethane foam composition can be in the range of 0.5:1 to 5:1. In some embodiments, the NCO / OH ratio of the isocyanate component to the polyol component can be within a range obtained by combining any two of the following endpoints: 0.5:1, 0.8:1, 1:1, 1.2:1, 1.5:1, 1.8:1, 2:1, 2.2:1, 2.5:1, 3:1, 4:1, and 5:1. In some particular embodiments, the NCO / OH ratio of the isocyanate component to the polyol component can be in the range of 0.5:1 to 4:1, or 0.5:1 to 3:1, preferably 0.5:1 to 2.5:1, 0.8:1 to 3:1, 0.8:1 to 2.5:1, 1:1 to 2.5:1, 1.2:1 to 2.2:1, or 0.8:1 to 2.0:1, more preferably 0.8:1 to 1.8:1, 1:1 to 2:1, 1.2:1 to 2:1, or 1:1 to 1.8:1.

[0041] As used herein, the term "NCO / OH ratio" refers to the ratio of the number of isocyanate groups to the number of hydroxyl groups in a polyurethane foam composition, or more specifically, the ratio of the number of isocyanate groups in the isocyanate component to the number of hydroxyl groups in the polyol component of the polyurethane composition.

[0042] In some embodiments, the polyurethane composition further comprises one or more catalysts, including amine compounds (e.g., tertiary amine compounds), organometallic compounds, and any combination thereof. Exemplary tertiary amine compounds include triethylenediamine, N-methylmorpholine, N,N-dimethylcyclohexylamine, N,N',N'-dimethylaminopropylhexahydrotriazine, 2-hydroxy-N,N,N-trimethylpropan-1-aminium formate, pentamethyldiethylenetriamine, tetramethylethylenediamine, 1-methyl-4-dimethylaminoethylpiperazine, 3-methoxy-N-dimethylpropylamine, N-ethylmorpholine, diethylethanolamine, N-cocomorpholine, N,N-dimethyl-N',N'-dimethylisopropylpropylenediamine, N,N-diethyl-3-diethylaminopropylamine, and dimethylbenzylamine. Exemplary organometallic catalysts include organomercury, organolead, organoferric, and organotin catalysts. Suitable tin catalysts include stannous chloride, tin salts of carboxylic acids such as dibutyltin dilaurate, and other organometallic compounds such as those disclosed in U.S. Pat. No. 2,846,408. Catalysts for the trimerization of polyisocyanates to give polyisocyanurates, such as alkali metal alkoxides, may also be optionally used herein. Such catalysts are used in amounts that measurably increase the rate of polyurethane formation. One or more catalysts may be included in either or both the polyol and isocyanate components. Typical amounts are 0.001 to 3 parts by weight of catalyst per 100 parts by weight of the polyol component. In some embodiments, the polyurethane composition includes an amine catalyst, a tin catalyst, or a mixture thereof.

[0043] In some embodiments, the polyurethane composition further comprises one or more blowing agents. The blowing agents used in the polyurethane composition include at least one physical blowing agent selected from a hydrocarbon, a hydrofluorocarbon, a hydrochlorofluorocarbon, a fluorocarbon, a dialkyl ether, or a fluorine-substituted dialkyl ether, or any combination thereof. These types of blowing agents include propane, isopentane, n-pentane, n-butane, isobutane, isobutene, cyclopentane, dimethyl ether, 1,1-dichloro-l-fluoroethane (HCFC-141b), chlorodifluoromethane (HCFC-22), l-chloro-l,l-difluoroethane (HCFC-142b), 1,1,1,2-tetrafluoroethane (HFC-134a), 1,1,1,3,3-pentafluorobutane (HFC-365mfc), 1,1-difluoroethane (HFC-152a), 1,1,1,2,3,3,3-heptafluoropropane (HFC-227ea), 1,1,1,3,3-pentafluoropropane (HFC-245fa), hydrofluoroolefins (HCFOs), hydrofluoroolefins (HFOs) such as LBAs, and any combination thereof. The polyurethane composition may also include a chemical blowing agent, such as water, a carboxylic acid, a formic acid, or any combination thereof. One or more blowing agents may be included in either or both of the polyol component and the isocyanate component. In some embodiments, one or more blowing agents are included in the polyol component. Typically, the blowing agent comprises 1 to 20 parts by weight per 100 parts by weight of the polyol component.

[0044] Optionally, the polyurethane composition further comprises one or more chain extending and / or cross-linking materials, examples of which include, but are not limited to, ethylene glycol, diethylene glycol, triethylene glycol, propylene oxide, propylene glycol, dipropylene glycol, tripropylene glycol, 1,4-butanediol, 1,6-hexanediol, 1,8-octanediol, cyclohexanedimethanol, glycerin, trimethylolpropane, trimethylolethane, pentaerythritol, sorbitol, and sucrose, as well as alkoxylates, diethanolamine, monoethanolamine, triethanolamine, mono-, di-, or tri(isopropanol)amine, glycerin, trimethylolpropane, and combinations thereof.

[0045] Optionally, the polyurethane composition further comprises one or more additives, such as fillers, antioxidants, preservatives, pigments, colorants, and flame retardant additives.

[0046] (A) Polyol component The polyol component included in the polyurethane composition includes one or more polyols. The one or more polyols included in the polyurethane composition can be selected from the group consisting of polyester polyols, polyether polyols, and any combination thereof.

[0047] In some embodiments, the polyol component comprises an SPE surfactant described herein, hi some embodiments, the polyol component comprises from 0.01% to 10%, e.g., 0.01%, 0.05%, 0.1%, 0.5%, or 0.8%, to 1%, 1.2%, 1.5%, 2%, 5%, 8%, or 10% by weight of the polyol component of an SPE surfactant described herein.

[0048] As used herein, the term "polyol" refers to a compound having two or more hydroxyl groups. A polyol is a "diol" if it has exactly two hydroxyl groups, a "triol" if it has exactly three hydroxyl groups, a "tetraol" if it has exactly four hydroxyl groups, a "pentanol" if it has exactly five hydroxyl groups, and so on.

[0049] In some embodiments, one or more polyols in the polyol component have an average hydroxyl group functionality of 2-8, for example, 2-7 or 3-6.

[0050] In some embodiments, one or more polyols in the polyol component have an average hydroxyl number of 25 to 1000 mg KOH / g, e.g., 25 to 900 mg KOH / g, 28 to 1000 mg KOH / g, or 28 to 900 mg KOH / g.

[0051] In some embodiments, the polyol component can include a polyester polyol. Compounds containing two or more ester linkages in the same linear chain of atoms are known herein as "polyesters." Compounds that are polyesters and polyols are known herein as "polyester polyols."

[0052] The polyester polyols used in the polyurethane composition may have a molecular weight not exceeding 10,000 g / mol.

[0053] In some embodiments, the polyester polyol can have a hydroxyl group functionality of at least 2 (i.e., f≧2). In some embodiments, the polyester polyol can have a hydroxyl group functionality not greater than 10 (i.e., f≦10). In some embodiments, the polyester polyol can have a hydroxyl group functionality in the range of 2-8, 2-7, 3-7, 3-6, or 3-5.

[0054] In some embodiments, the polyester polyol may have a hydroxyl group count greater than 25 mg KOH / g. In some embodiments, the polyester polyol may have a hydroxyl group count less than 1,000 mg KOH / g. In some embodiments, the polyester polyol may have an average hydroxyl group count of 25 to 950 mg KOH / g, 25 to 900 mg KOH / g, 27 to 1,000 mg KOH / g, 27 to 950 mg KOH / g, 28 to 1,000 mg KOH / g, or 28 to 950 mg KOH / g.

[0055] In some embodiments, polyester polyols include, but are not limited to, polycondensates of diols, and optionally polyols (e.g., triols, tetraols), dicarboxylic acids, and optionally polycarboxylic acids (e.g., tricarboxylic acids, tetracarboxylic acids), or hydroxycarboxylic acids or lactones. Polyester polyols can also be derived from the corresponding polycarboxylic acid anhydrides, or corresponding polycarboxylic acid esters of lower alcohols, instead of the free polycarboxylic acids.

[0056] Suitable diols include, but are not limited to, polyalkylene glycols such as ethylene glycol, butylene glycol, diethylene glycol, triethylene glycol, pentylene glycol, hexalene glycol, polyethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, 1,6-hexanediol, and neopentyl glycol. If a polyester polyol functionality greater than 2 is to be achieved, a polyol having a functionality of 3 or greater (e.g., trimethylolpropane, glycerol, erythritol, pentaerythritol, trimethylolbenzene, or trishydroxyethyl isocyanurate) can optionally be included in the polyol composition.

[0057] Suitable dicarboxylic acids include, but are not limited to, fatty acids, aromatic acids, and combinations thereof. Examples of suitable aromatic acids include phthalic acid, isophthalic acid, terephthalic acid, and tetrahydrophthalic acid. Examples of suitable aliphatic acids include hexahydrophthalic acid, cyclohexanedicarboxylic acid, adipic acid, azelaic acid, sebacic acid, glutaric acid, tetrachlorophthalic acid, maleic acid, fumaric acid, itaconic acid, malonic acid, suberic acid, 2-methylsuccinic acid, 3,3-diethylglutaric acid, 2,2-dimethylsuccinic acid, and trimellitic acid. As used herein, the term "acid" also includes any anhydrides of the acid. Furthermore, monocarboxylic acids such as benzoic acid and hexanecarboxylic acid should be minimized or eliminated from the disclosed compositions. Saturated aliphatic and / or aromatic acids such as adipic acid or isophthalic acid are also suitable for use in accordance with the present disclosure.

[0058] In some embodiments, the polyol component may include a polyether polyol.

[0059] A compound containing two or more ether linkages in the same linear chain of atoms is known herein as a "polyether." A compound that is a polyether and a polyol is a "polyether polyol."

[0060] The polyether polyols used in the polyurethane composition may have a molecular weight not exceeding 10,000 g / mol.

[0061] In some embodiments, the polyether polyol may have a hydroxyl group functionality of at least 2 (i.e., f≧2). In some embodiments, the polyether polyol may have a hydroxyl group functionality of no more than 10 (i.e., f≦10). In some embodiments, the polyether polyol may have a hydroxyl group functionality in the range of 2-8, 2-7, 3-7, 3-6, or 3-5.

[0062] In some embodiments, the polyether polyol may have a hydroxyl group number of greater than 25 mg KOH / g. In some embodiments, the polyether polyol may have a hydroxyl group number of less than 1,000 mg KOH / g. In some embodiments, the polyether polyol may have an average hydroxyl group number of 25 to 950 mg KOH / g, 25 to 900 mg KOH / g, 27 to 1,000 mg KOH / g, 27 to 950 mg KOH / g, 28 to 1,000 mg KOH / g, or 28 to 950 mg KOH / g.

[0063] In some embodiments, polyether polyols for use in the present disclosure are obtained by the addition polymerization of alkylene oxides with polyhydric alcohol starter compounds. Examples of such polyhydric alcohols include glycerin, sorbitol, sucrose, glucose, fructose, lactose, or other sugars. In some embodiments, the starter compound is sorbitol or sucrose. These polyhydric alcohols, as well as mixtures of these alcohols with water, glycerol, propylene glycol, ethylene glycol, or diethylene glycol, can be used as starter compounds. Examples of suitable sorbitol- or sucrose / glycerin-initiated polyethers that can be used include VORANOL™ 360, VORANOL™ RN411, VORANOL™ RN490, VORANOL™ 370, VORANOL™ 446, VORANOL™ 520, VORANOL™ 550, VORANOL™ RN482, TERCAROL™ RF55, or VORANOL™ RH360 polyols, all available from The Dow Chemical Company.

[0064] In some embodiments, the polyol component can have a viscosity of from 200 cSt to 38,000 cSt, eg, from 200 cSt to 35,000 cSt, or from 250 cSt to 35,000 cSt at 25° C., as measured according to ASTM D2196.

[0065] (B) Isocyanate component The isocyanate component included in the polyurethane composition includes one or more isocyanate compounds that react with one or more polyols in the polyol component.

[0066] In some embodiments, the isocyanate component comprises an SPE surfactant described herein, hi some embodiments, the isocyanate component comprises from 0.01% to 10%, e.g., 0.01%, 0.05%, 0.1%, 0.5%, or 0.8%, to 1%, 1.2%, 1.5%, 2%, 5%, 8%, or 10% by weight of the isocyanate component of an SPE surfactant described herein.

[0067] In some embodiments, the isocyanate compound can be one or more selected from isocyanate monomers, isocyanate prepolymers, modified isocyanates, and combinations thereof.

[0068] As used herein, an "isocyanate monomer" is any compound containing two or more isocyanate groups. An "aromatic isocyanate" is an isocyanate that contains one or more aromatic rings. An "aliphatic isocyanate" does not contain an aromatic ring. In some embodiments, the isocyanate compound comprises an aromatic isocyanate.

[0069] Suitable isocyanate monomers for use according to the present disclosure may be selected from the group consisting of aromatic isocyanates, aliphatic isocyanates, carbodiimide-modified isocyanates, and combinations thereof. Examples of aromatic isocyanates suitable for use according to the present disclosure include, but are not limited to, isomers of methylene diphenyl dipolyisocyanate ("MDI") such as 4,4-MDI, 2,4-MDI, and 2,2'-MDI, or modified MDI such as carbodiimide-modified MDI, urethane-modified MDI, or allophanate-modified MDI; isomers of toluene-dipolyisocyanate ("TDI"), such as 2,4-TDI and 2,6-TDI; isomers of naphthalene-dipolyisocyanate ("NDI"), such as 1,5-NDI; and combinations thereof. Examples of aliphatic polyisocyanates suitable for use according to the present disclosure include, but are not limited to, isomers of hexamethylene dipolyisocyanate ("HDI"), isophorone dipolyisocyanate ("IPDI"), xylene dipolyisocyanate ("XDI"), methylene-bis-(4-cyclohexylisocyanate) ("HMDI"), and combinations thereof. In some embodiments, the isocyanate monomer comprises a diisocyanate monomer selected from the group consisting of isophorone diisocyanate (IPDI), methylene-bis-(4-cyclohexylisocyanate) (HMDI), hexamethylene diisocyanate (HDI), methylene diphenyl diisocyanate (MDI), toluene diisocyanate (TDI), and combinations thereof.

[0070] In some embodiments, the isocyanate component of the polyurethane composition can be prepared using any organic polyisocyanate, modified polyisocyanate, isocyanate-based prepolymer, and mixtures thereof. These can include aliphatic and cycloaliphatic isocyanates, but aromatic and especially polyfunctional aromatic isocyanates are preferred, such as 2,4- and 2,6-toluene diisocyanate and the corresponding isomer mixtures; 4,4'-, 2,4'-, and 2,2'-diphenylmethane diisocyanate (MDI) and the corresponding isomer mixtures; mixtures of 4,4'-, 2,4'-, and 2,2'-diphenylmethane diisocyanate with polyphenylpolymethylene polyisocyanate (PMDI); and mixtures of PMDI and toluene diisocyanate. Most preferably, the polyisocyanate used to prepare the prepolymer formulation of the present invention is MDI or PMDI, or a crude mixture of either of these.

[0071] In some embodiments, the isocyanate component can have a viscosity of 50 mPa·s to 20,000 mPa·s, 50 mPa·s to 18,000 mPa·s, or 100 mPa·s to 18,000 mPa·s at 25° C. as measured according to ASTM D2196.

[0072] In some embodiments, the amount of odorous components produced from a polyol component and / or an isocyanate component containing a stabilized SPE surfactant is less (e.g., 30%, 40%, 50%, 60%, 70%, 80%, 90%, or 95% or more less) than a polyol component and / or an isocyanate component containing the same SPE surfactant but not stabilized according to the present disclosure after a storage period of about 14 days at 25° C. or after accelerated aging for more than 5 days at 80° C. The odorous components can be one or more selected from aldehydes (e.g., propionaldehyde), cyclic ethers (e.g., trioxocane, EMD, DMD), or mixtures thereof.

[0073] D. Polyurethane products In a further aspect, the present disclosure provides polyurethane articles formed using the polyurethane compositions described above.

[0074] In some embodiments, the polyurethane product is a polyurethane foam.

[0075] Generally, polyurethane foams can be formed by (i) providing a polyurethane composition comprising the (A) polyol component and (B) isocyanate component described above; (ii) forming a reaction mixture by mixing the (A) polyol component with the (B) isocyanate component; and (iii) subjecting the reaction mixture to conditions such that it reacts, expands, and cures to form the polyurethane foam.

[0076] The (A) polyol component and the (B) isocyanate component are as described above in the "C. Polyol Composition" section.

[0077] In some embodiments, the reaction mixture reacts, expands, and cures within the enclosed space to form a polyurethane foam within the enclosed space, hi some embodiments, the reaction mixture reacts, expands, and cures at or above room temperature.

[0078] In some embodiments, polyurethane products made using stabilized SPE surfactants emit less odorous compounds (e.g., 30%, 40%, 50%, 60%, 70%, 80%, 90%, or 95% or more less) than polyurethane products made using the same SPE surfactants but not stabilized according to the present disclosure after about 14 days of storage at 25° C. or after more than 5 days of accelerated aging at 80° C. The odorous compounds can be one or more selected from aldehydes (e.g., propionaldehyde), cyclic ethers (e.g., trioxocane, EMD, DMD), or mixtures thereof.

[0079] E. Use and Application In a further aspect, the present disclosure provides the use of a stabilized SPE surfactant as described herein in the manufacture of a polyurethane composition.

[0080] In some embodiments, the polyurethane composition is a polyurethane foam composition.

[0081] In a further aspect, the present disclosure provides the use of a stabilized SPE surfactant as described herein in the manufacture of a polyurethane product.

[0082] In some embodiments, the polyurethane product is a polyurethane foam. [Example]

[0083] Certain embodiments of the present invention are now illustrated in the following examples, in which all parts and percentages are by weight unless otherwise specified.

[0084] 1. Reagents and Chemicals

[0085] [Table 1]

[0086] The structures of some of the exemplary pretreatment additives listed above are shown below.

[0087] [ka]

[0088] 2. Sample Preparation 2.1 Preparation of compounded polyols used to produce foams Detailed formulations are described in Examples CE10 and IE10. a. The above additives were first mixed with the SPE surfactant or polyol based on the formulation in the example table below (see formulation below for individual results). b. The mixture of surfactant or polyol and additive was stored at 25°C overnight. c. The other ingredients were added to the above mixture, and then mixed with a stirrer at a speed of 3000 RPM for 3 minutes to obtain compounded polyol as Part A. The compounded polyol was then stored at 25°C for 12-24 hours before foaming.

[0089] 2.2 Foaming procedure Foam samples were prepared by mixing 106.69 g aliquots of the compounded polyol with 58.4 g of TDI isocyanate. After foaming, the foam samples were wrapped in aluminum foil. Gas bag analysis was performed within 7 days of foam sample preparation.

[0090] 3. Determination of odorous substances in SPE surfactants and foams 3.1 Sample preparation Samples (0.3 g) were placed in 20 mL headspace GC-MS vials for analysis.

[0091] 3.2 SPME (solid phase micro-extraction) GC-MS method parameters SPME GC-MS analysis was performed on an Agilent 7890 gas chromatograph connected to a mass spectrometry detector (Agilent 5975C MSD). The GC conditions are listed in the table below. Semi-quantification was performed by reference standards (5 ppm each, prepared in Polyol 8010). The LOQ (limit of quantification or detection) of the method for the various cyclic ethers is approximately 0.01 ppm.

[0092] [Table 2]

[0093] 4. Examples and Tests 4.1 Comparison of commercial SPE and pretreated SPE Amine catalysts were tested to validate the concept of using an amine catalyst to pretreat the surfactant NIAX™ Silicone L-650 to reduce the formation of cyclic ethers during storage of the surfactant. Thus, the surfactant was compared to various pretreated versions, and Table 1 shows the stability of the commercial SPE grade compared to the pretreated SPE grade after accelerated aging to simulate long-term storage.

[0094] Thus, Comparative Example 1 (CE1), which corresponds to a commercial SPE grade, shows substantial formation of cyclic ethers after accelerated aging, with DMD levels increasing from 0.01 ppm at time 0 to 0.11 ppm after 6 days at 80°C.

[0095] Comparative Example 2 (CE2), corresponding to a commercial SPE pretreated with water, shows similar cyclic ether formation after aging as CE1. Of the three cyclic ethers, trioxocane formation increases more rapidly during the initial portion of the test, reflecting the effect of the presence of water. Pretreatment of the SPE with antioxidant AO1135 (CE3) has some effect in reducing cyclic ether formation after aging, with cyclic ether levels lower than in CE1, but the effect is limited and may be insufficient to address odor issues.

[0096] The most dramatic effect on the formation of cyclic ethers after aging relates to Inventive Example 1 (IE1), which corresponds to an SPE pretreated with the amine catalyst Jeffcat™ ZR50, showing that the amount of cyclic ethers remains almost unchanged after 6 days of accelerated aging at 80°C.

[0097] [Table 3]

[0098] 4.2 Comparison of commercial SPE and SPE pretreated with various amines SPEs pretreated with various amines were evaluated and compared with commercially available SPEs. Acetic acid, which is frequently observed in SPE surfactants (from acetaldehyde oxidation), was included in the pretreatment. Note that most of the amines used here are typical amine catalysts used in PU foam formulations.

[0099] In Table 2, CE4 corresponds to the commercial SPE, while CE5 corresponds to the commercial SPE pretreated with water; therefore, these two comparative examples reproduce the same composition as already mentioned in Table 1, but the difference here is the type of aging treatment (16 hours at 80°C) and the type of test (headspace SMPE).

[0100] CE6 and CE7 correspond to SPEs pretreated with acetic acid. The amount of degradation products produced, especially odorous compounds such as propionaldehyde and cyclic ethers, increased substantially after aging, indicating that acid pretreatment exacerbates the formation of odorous compounds after aging of SPEs.

[0101] Inventive Examples IE2, IE3, and IE4 correspond to SPEs pretreated with various levels of JEFFCAT™ ZR-50, with or without water. Results after accelerated aging show a substantial reduction in the amount of propionaldehyde detected.

[0102] Inventive Examples IE5, IE6, and IE7 correspond to SPEs pretreated with other amines, and again compared to the comparative examples, after accelerated aging the inventive examples show a substantial reduction in the amount of propionaldehyde detected.

[0103] Prior to testing, the samples were aged for 16 hours at 80° C. Despite the relatively short accelerated aging time, the experimental data confirms the benefits of using the concepts of the present invention, although the experiment is limited to the quantification of propionaldehyde.

[0104] Pretreatment of SPEs with basic compounds, such as those considered in the examples of the present invention reported in Table 2, can stabilize the SPEs such that the formation of odorous compounds during storage is substantially reduced.

[0105] Example IE4 is particularly interesting because it shows that the amount of basic compound is effective even when used at low levels. In fact, IE4 corresponds to an SPE surfactant pretreated with only 1% basic compound.

[0106] It should also be noted that compounded polyols typically also contain amine catalysts, however, these amine catalysts may not be as effective at stabilizing the SPE surfactant since most of the cyclic ethers may have already formed during shipping and storage of the surfactant.

[0107] [Table 4] NOTE: For propionaldehyde, the results were reported as peak area because conversion of peak area to ppm could not be accurately performed, and therefore it was decided to leave the results expressed as peak area as this better reflected the concentration of the odorous species in the sample.

[0108] 4.3 Commercially Available SPEs, Non-Amine Stabilized and Stabilized: Polyol and Foam Testing Previous examples have shown that commercially available SPEs can exhibit degradation during storage, potentially resulting in the formation of odorous compounds. It has also been shown that pre-treating SPEs with basic compounds can substantially reduce the rate of degradation, thus resulting in pre-treated SPEs with lower odorous compound content.

[0109] Here, we show that the amount of odorous degradation products present in the SPE can directly influence the presence of odorous components in the final PU foam.

[0110] Thus, Table 3 shows that after 10 days of accelerated aging at 80° C., the commercial SPE surfactant contained significant amounts of propionaldehyde and significant amounts of cyclic ethers (see CE8). In contrast to the same SPE surfactant pretreated with stabilizers, these same odorous components were present in much lower amounts (see IE8).

[0111] Table 4 shows the detected amounts of propionaldehyde and cyclic ethers present in compounded polyols prepared with the commercial SPEs or pretreated SPEs described in Table 3. The data show that the higher amounts of propionaldehyde and cyclic ethers associated with the aged commercial SPE grades are reflected in proportionally higher amounts of the same odorous components in the compounded polyols.

[0112] The compounded polyol samples were prepared as follows: The various compounding ingredients (see recipe below) were mixed with a stirrer at a speed of 3000 RPM for 3 minutes. The two compounded polyols were then stored at 25°C for approximately 2 hours before being tested for degradation products.

[0113] Table 5 shows the detected amounts of propionaldehyde and cyclic ethers present in PU foams prepared using the blended polyols from Table 4. The data show that the higher amounts of propionaldehyde and cyclic ethers associated with the aged commercial SPE grades are reflected in proportionally higher amounts of the same odorous components in the final foam.

[0114] The foaming procedure was as follows: Foam samples were prepared by mixing 106.69 g of an aliquot of compounded polyol with 58.4 g of Isocyanate 1 using a stirrer at a speed of 3000 RPM for 1 minute. After foaming, the foam samples were wrapped in aluminum foil. Gas bag analysis was performed 3 days after the foam sample preparation.

[0115] [Table 5]

[0116] [Table 6]

[0117] [Table 7]

[0118] [Table 8]

[0119] The data in Table 5 show that the quality of the SPE can have a significant impact on the amount of odorous compounds present in the foam, even though the amount of SPE surfactant is only about 1% of the total PU foam mass. The use of pretreated SPE surfactants makes it possible to reduce the amount of odorous compounds, especially trioxocane.

[0120] [Table 9] Note: The data in Table 6 expands on the type of test already described in Table 1. Specifically, samples were tested within 24 hours of preparation (freshly prepared) and analyzed after 2 weeks of storage at room temperature. The LOQ for this method was 0.01 ppm. Detection was limited to trioxocane only.

[0121] A variety of amines with different pKb were selected for this study. It was shown that most of the amines behaved similarly in inhibiting the decomposition of unsaturation and the formation of trioxocane. Strong bases, such as KOH, showed negative effects. A pKb between 2.8 and 5.0 performed best. Higher pKb amines, such as aniline and diphenylamine, showed some effectiveness, but not as well as the others.

[0122] [Table 10] Note: Samples were tested within 24 hours after preparation (freshly prepared) and analyzed after 2 weeks of storage at room temperature.

[0123] Polyol 2 and ZR-50 were selected to examine the effect of loading ratio. ZR-50 maintained its inhibitory effect down to 0.01%, but its effectiveness decreased as the loading ratio decreased. Two experiments using Polyol 2 showed that it also worked because it contained a tertiary amine structure, but compared to ZR-50, there was a difference in equivalent weight, approximately 10-fold. Therefore, to achieve a similar effect on stability, the wt% loading level of Polyol 2 in the surfactant would have to be approximately 10-fold higher than that of ZR-50. Higher amine ratios resulted in better inhibitor performance, but a balance must be struck between performance and potential adverse side effects from the amine.

Claims

1. A method for stabilizing a silicone polyether (SPE) surfactant formed by grafting a vinyl polyether onto a silicone backbone, the method comprising pretreating the SPE surfactant with a basic compound having a pKb of 1.0 to 9.

0.

2. 10. The method of claim 1, wherein the amount of the basic compound used to pre-treat the SPE surfactant is from 0.01% to 15% by weight of the SPE surfactant.

3. The method of claim 1 , wherein the basic compound comprises an amine.

4. 4. The method of claim 3, wherein the amine is selected from the group consisting of a primary amine, a secondary amine, a tertiary amine, and any mixture thereof.

5. 4. The method of claim 3, wherein the amine has a pKb of 2.8 to 5.

0.

6. The method of claim 3 wherein the amine has at most one hydroxyl group.

7. 10. The method of claim 1, wherein pre-treatment of the SPE surfactant with a basic compound having a pKb of 1.0 to 9.0 occurs after the SPE surfactant is synthesized.

8. A stabilized SPE surfactant obtainable by the method of claim 1.

9. 1. A polyurethane composition comprising: (A) a polyol component comprising one or more polyols selected from the group consisting of polyester polyols, polyether polyols, and combinations thereof; (B) an isocyanate component comprising one or more isocyanate compounds; Including, A polyurethane composition, wherein the (A) polyol component and / or the (B) isocyanate component comprises a stabilized SPE surfactant obtained by the method of claim 1.

10. 10. The polyurethane composition of claim 9, which is a polyurethane foam composition.

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