Low-odor silicone polyether type surfactant and application thereof in polyurethane composition

Abstract

The present disclosure relates to low odor silicone polyether surfactants and their use in polyurethane compositions. The present disclosure provides a method of stabilizing an SPE surfactant formed by grafting a vinyl polyether onto a silicone backbone, the method comprising pre-treating the SPE surfactant with a basic compound having a pKb of 1.0 to 9.0. The present disclosure also provides a 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)-based surfactants. More specifically, the present disclosure relates to low-odor stable silicone polyether-based surfactants, their preparation, and their use in polyurethane compositions. Background Art

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

[0003] Analytical work conducted to identify the cause of musty odors in flexible polyurethane foams indicated that trioxoctane and its isomers were one of the root causes of the malodor (see, e.g., SH Harris et al., "Characterization of Polyurethane Foam Odor Bodies," Polyurethanes World Congress 1987, Aachen, Germany, pp. 848-851). This is surprising in view of the relatively high boiling point of trioxoctane (220° C.), and it emphasizes the strong olfactory capabilities associated with this type of molecule.

[0004] The problem of malodor in polyurethane foams has become an industrial challenge. Various solutions have been proposed, such as the use of reactive amine catalysts (see, for example, US8563676B2), or the use of formulation ingredients synthesized in a manner to reduce the presence of volatile species (see, for example, CN111247188A). However, the contribution of aldehydes and cyclic ethers to the overall odor of polyurethane products has not been fully understood to date. There is some understanding of how cyclic ethers are formed, but this understanding is limited, especially for polyurethane systems, and therefore no effective solutions have been proposed to address this challenge.

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

[0006] In one aspect, the present disclosure provides a method of stabilizing a 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.

[0007] In another aspect, the present disclosure provides a stable SPE surfactant obtained by the method described herein.

[0008] In another aspect, the present disclosure provides a polyurethane composition comprising,

[0009] (A) a polyol component comprising one or more polyols selected from the group consisting of polyester polyols, polyether polyols, and combinations thereof; and

[0010] (B) an isocyanate component, the isocyanate component comprising one or more isocyanate compounds,

[0011] wherein the (A) polyol component and / or the (B) isocyanate component comprises a stabilized SPE surfactant obtained by the method for stabilizing a SPE surfactant described herein.

[0012] In another aspect, the present disclosure provides a polyurethane product formed using the polyurethane composition described herein.

[0013] In another aspect, the present disclosure provides for use of a stable SPE surfactant described herein in the manufacture of a polyurethane composition.

[0014] In another aspect, the present disclosure provides for use of the stable SPE surfactants described herein in the manufacture of a polyurethane product.

[0015] 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

[0016] 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 the invention belongs. In addition, all publications, patent applications, patents, and other references mentioned herein are incorporated by reference.

[0017] As disclosed herein, “and / or” means “and, or as an alternative.” Unless otherwise indicated, all ranges are inclusive.

[0018] As disclosed herein, all percentages referred to herein are by weight and temperatures are in °C unless otherwise stated.

[0019] A. Stability of SPE surfactants

[0020] The odor problem in polyurethane foams has long been an unsolved problem in the art, and the understanding of the causes is very limited.

[0021] 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 odor components in polyurethane foams, especially flexible polyurethane foams used in furniture and bedding applications.

[0022] SPE surfactants are widely used as surfactants in flexible and rigid polyurethane foams. They are generally formed by grafting vinyl polyethers onto a silicone backbone. The inventors have found that the manufacture of SPE surfactants (during which some materials, such as vinyl polyethers, may be used in excess to ensure completion of the hydrosilylation reaction) may result in the following: the SPE surfactants produced contain unsaturated species that may degrade during storage to form aldehydes and cyclic ethers, thereby causing odor problems in polyurethane foams. This means that the use of SPE surfactants may have different effects on the final odor of polyurethane foams, depending on the amount of unsaturated species initially present in the SPE surfactants and the storage time and storage conditions of the SPE surfactants. This finding is surprising because SPE surfactants are generally present in fully flexible polyurethane formulations in amounts of only about 1%, and it is expected that their effect on the final foam odor is negligible. Contrary to previous understandings, the inventors have demonstrated that even when used at low levels, SPE surfactants can still lead to the formation of a large amount of odor components in the final polyurethane foam.

[0023] In one aspect, the present disclosure provides a method of stabilizing a 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.

[0024] As used herein, "SPE surfactants" are generally silicone surfactants with a siloxane backbone and polyether side groups. SPE surfactants may be non-hydrolyzable or hydrolyzable. Non-hydrolyzable surfactants in which the polyether side groups are connected to the siloxane backbone via Si-C bonds are generally considered to have high efficacy, but produce "tight" polyurethane foams with poor air permeability. Hydrolyzable surfactants in which the polyether side groups are connected to the siloxane backbone via Si bonds are generally considered to have low efficacy, but provide good processing characteristics, and produce polyurethane foams with good air permeability. In some embodiments, SPE surfactants can be obtained by the reaction of hydrogen siloxanes (e.g., organohydrogen siloxanes) and polyether compounds with aliphatic unsaturated groups in the presence of a hydrosilylation catalyst. Methods for preparing SPE surfactants are known in the art and can be found in a large number of documents, for example, European Patent No. EP1081182 (B1), which is incorporated herein by reference in its entirety.

[0025] In some embodiments, pre-treating the SPE surfactant with the basic compound includes combining (eg, mixing) the SPE surfactant with the basic compound.

[0026] In some embodiments, the amount of the alkaline compound used to pretreat the SPE surfactant is 0.01% to 15% by weight of the SPE surfactant. In some embodiments, the amount of the alkaline compound used to pretreat the SPE surfactant is in the range obtained by combining any two of the following endpoints: 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% by weight of the SPE surfactant. In an exemplary embodiment, the amount of the alkaline compound used to pretreat the SPE surfactant is 0.05% to 15%, 0.1% to 15%, 0.01% to 14%, or 0.05% to 14% by weight of the SPE surfactant.

[0027] In some embodiments, the basic compound is a liquid at room temperature with a melting point below 20°C.

[0028] In some embodiments, the basic compound has a pKb of 1.0 to 9.0. In some embodiments, the basic compound has a pKb in the 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 an exemplary embodiment, the basic compound has a pKb of 2.0 to 9.0, 2.0 to 8.0, 2.0 to 6.0, 2.0 to 5.0, 2.5 to 5.0, 2.8 to 5.0, or 3.0 to 5.0.

[0029] In some embodiments, the basic compound comprises an amine.

[0030] 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 one, two or three. The hydrocarbon residue may be part of a straight or branched aliphatic hydrocarbon structure, or may be part of an aliphatic hydrocarbon structure in which a cyclic structure such as a five-membered ring and a six-membered ring is formed, or may be an aromatic hydrocarbon. In addition, halogens such as fluorine, chlorine and bromine and functional groups such as hydroxyl and nitrile groups may be combined with these aliphatic hydrocarbon residues or aromatic hydrocarbon residues.

[0031] 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, wherein only one of the hydrogen atoms in the ammonia molecule is replaced. The term "secondary amine" refers to an amine having an ammonia molecule, wherein two of the hydrogen atoms in the ammonia molecule are replaced. The term "tertiary amine" refers to an amine having an ammonia molecule, wherein three of the hydrogen atoms in the ammonia molecule are replaced. In a specific embodiment, the amine comprises a tertiary amine.

[0032] In some embodiments, amine can be selected from amine additives (e.g., amine catalysts) used in polyurethane foam formulations. In some embodiments, amine can be selected from primary amine catalysts, secondary amine catalysts, tertiary amine catalysts, or any mixture thereof. In some embodiments, amine includes tertiary amine catalysts. Tertiary amine catalysts include organic compounds containing at least one tertiary nitrogen atom and 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.

[0033] Exemplary amine additives can include, but are not limited to, 1-butylamine, di-n-butylamine, triethylenediamine, trimethylamine, triethylamine, tripropylamine, tributylamine, tripentylamine, pyridine, quinoline, piperazine, tetramethylbutylene diamine, pentamethyldiethylenetriamine, N,N-dimethylethanolamine, N,N-dimethylbenzylamine, N,N-dimethylpiperazine, morpholine, N-ethylmorpholine, N-cocoyl-morpholine, bis(dimethylaminoethyl) ether, N-methylmorpholine, N-ethylpiperidine, 2-methylpropylene diamine, methyltriethylenediamine, 2,4,6-tris(2-methylaminoethyl) ... dimethylamino-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-dimethylaminopropyl) 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-dimorpholinyl diethyl ether, N-methylimidazole, dimethylaminopropyl dipropanolamine, 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-vinylpiperidine, methylhydroxyethylpiperazine, pentamethyldiethylene triamine, 1,4-diazobicyclo-2,2,2-octane, dimethylalkylamines wherein the alkyl group contains 4 to 18 carbon atoms, dimethylethanolamine (DMEA), tetramethyliminodipropylamine (e.g., Polycat 15), N,N-dimethylcyclohexylamine (DMCHA), tetraethylenediamine (e.g., Dabco / TEDA), 2-[2-(dimethylamino)ethoxy]ethanol (DMEE) and N,N-bis(3-dimethylaminopropyl)-N-isopropanolamine (e.g., JEFFCAT ZR-50), and mixtures thereof.

[0034] As used herein, "pre-treatment" or "pre-treating" of an SPE surfactant means that the SPE surfactant is treated before its subsequent application (e.g., in a polyurethane composition). In some embodiments, pre-treatment or stabilization of the SPE surfactant with an alkaline compound as described herein is performed after the synthesis or preparation of the SPE surfactant. In other words, the alkaline compound is added to the SPE surfactant after the synthesis or preparation of the SPE surfactant is completed. One or more alkaline compounds commonly used during the synthesis or preparation of the SPE surfactant are not sufficient to be considered as pre-treatment or stabilization as described herein. In some embodiments, pre-treatment or stabilization is performed after the preparation of the SPE surfactant is completed and before it is packaged or stored.

[0035] The present inventors have found that by pre-treating the SPE surfactant according to the present disclosure, the SPE surfactant can be stabilized and the degradation of the SPE surfactant 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 the SPE surfactants so treated.

[0036] B. Stable SPE Surfactants

[0037] In another aspect, the present disclosure provides a stable SPE surfactant obtained by the method described above.

[0038] As described above, "stable SPE surfactant" refers to an SPE surfactant that is pretreated or stabilized with an alkaline compound. In some embodiments, the stable SPE surfactant includes an SPE surfactant mixed with an alkaline compound. In some embodiments, the alkaline compound is mixed with the SPE surfactant after the synthesis or preparation of the SPE surfactant is completed.

[0039] In some embodiments, the amount of the alkaline compound included in the stable SPE surfactant is 0.01% to 15% by weight of the SPE surfactant. In some embodiments, the amount of the alkaline compound used to pretreat the SPE surfactant is in the range obtained by combining any two of the following endpoints: 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% by weight of the SPE surfactant. In an exemplary embodiment, the amount of the alkaline compound used to pretreat the SPE surfactant is 0.05% to 15%, 0.1% to 15%, 0.01% to 14%, or 0.05% to 14% by weight of the SPE surfactant.

[0040] In some embodiments, after storage for a duration of about 14 days at 25° C., or after accelerated aging for more than 5 days at 80° C., the amount of odor components generated by the stabilized SPE surfactant is lower (e.g., 30%, 40%, 50%, 60%, 70%, 80%, 90%, or 95% or more lower) than the amount of odor components generated by the same SPE surfactant that has not been stabilized according to the present disclosure. The odor component can be one or more selected from aldehydes (e.g., propionaldehyde), cyclic ethers (e.g., trioxoctane, EMD, DMD), or mixtures thereof.

[0041] The SPE surfactants and the basic compounds that stabilize the SPE surfactants are described above in the section "A. Stabilization of SPE Surfactants".

[0042] C. Polyurethane Composition

[0043] In another aspect, the present disclosure provides a polyurethane composition comprising,

[0044] (A) a polyol component comprising one or more polyols selected from the group consisting of polyester polyols, polyether polyols, and combinations thereof; and

[0045] (B) an isocyanate component, the isocyanate component comprising one or more isocyanate compounds,

[0046] wherein the (A) polyol component and / or the (B) isocyanate component comprises a stabilized SPE surfactant obtained by the method for stabilizing a SPE surfactant described herein.

[0047] 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.

[0048] As used herein, the term "two-component" means that the polyurethane foam composition is provided in separate parts before use. Generally, the composition according to the present disclosure may include at least a first component and a second component, the first component comprising one or more polyols selected from the group consisting of polyester polyols, polyether polyols and combinations thereof (also referred to herein as "polyol components", "polyol components (A)" or "OH components"), and the second component comprising one or more isocyanate compounds (also referred to herein as "isocyanate components", "isocyanate components (B)" or "NCO components"). The polyol component and the isocyanate component can be prepared, stored, transported and supplied separately, and combined shortly before or immediately before application to, for example, a product to be potted. It is expected that when the two components are contacted, a curing reaction begins, wherein the polyol groups react with the isocyanate groups to form urethane segments. The reactive polyurethane dispersion formed by contacting the two components may be referred to as a "reaction mixture" or a "curable mixture".

[0049] In some embodiments, the NCO / OH ratio of the isocyanate component to the polyol component contained in the polyurethane foam composition may 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 may be in the 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 specific 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; and 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.

[0050] 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 the polyurethane foam composition; or more specifically, the ratio between the number of isocyanate groups in the isocyanate component of the polyurethane composition and the number of hydroxyl groups in the polyol component.

[0051] 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'-dimethylaminopropyl hexahydrotriazine, formic acid 2-hydroxy-N,N,N-trimethylpropane-1-ammonium, pentamethyldiethylenetriamine, tetramethylethylenediamine, 1-methyl-4-dimethylaminoethylpiperazine, 3-methoxy-N-dimethylpropylamine, N-ethylmorpholine, diethylethanolamine, N-coconut oil morpholine, N,N-dimethyl-N',N'-dimethylisopropylpropylenediamine, N,N-diethyl-3-diethylaminopropylamine, and dimethylbenzylamine. Exemplary organometallic catalysts include organic mercury, organic lead, organic iron, and organic tin 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. Patent No. 2,846,408. Catalysts such as alkali metal alkoxides for the trimerization of polyisocyanates to produce polyisocyanurates may also be optionally employed herein. Such catalysts are used in an amount that measurably increases the rate of polyurethane formation. One or more catalysts may be included in either or both of the polyol component and the isocyanate component. A typical amount is a catalyst of 0.001 to 3 parts by weight 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.

[0052] In some embodiments, the polyurethane composition further comprises one or more blowing agents. The blowing agent used in the polyurethane composition includes at least one physical blowing agent selected from hydrocarbons, hydrofluorocarbons, hydrochlorofluorocarbons, fluorocarbons, dialkyl ethers or fluorine-substituted dialkyl ethers, or any combination thereof. These types of blowing agents include propane, isopentane, n-pentane, n-butane, isobutane, isobutylene, cyclopentane, dimethyl ether, 1,1-dichloro-1-fluoroethane (HCFC-141b), chlorodifluoromethane (HCFC-22), 1-chloro-1,1-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 (HCFO), hydrofluoroolefins (HFO) such as LBA, and any combination thereof. The polyurethane composition may also include a chemical blowing agent, such as water, carboxylic acid, formic acid and 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 accounts for 1 to 20 parts by weight per 100 parts by weight of the polyol component.

[0053] Optionally, the polyurethane composition further comprises one or more chain extending and or crosslinking materials. Examples of such materials 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, glycerol, trimethylolpropane, trimethylolethane, pentaerythritol, sorbitol, and sucrose, as well as alkoxylates, diethanolamine, monoethanolamine, triethanolamine, mono-(isopropanol)amine, di-(isopropanol)amine or tri-(isopropanol)amine, glycerol, trimethylolpropane, and combinations thereof.

[0054] Optionally, the polyurethane composition further comprises one or more additives, such as fillers, antioxidants, preservatives, pigments, colorants, and flame retardant additives.

[0055] (A) Polyol component

[0056] The polyol component included in the polyurethane composition includes one or more polyols. The one or more polyols included in the polyurethane composition may be selected from the group consisting of polyester polyols, polyether polyols, and any combination thereof.

[0057] In some embodiments, the polyol component includes an SPE surfactant described herein. In some embodiments, the polyol component includes an SPE surfactant described herein from 0.01% to 10% by weight of the polyol component, for example, from 0.01%, 0.05%, 0.1%, 0.5%, or 0.8% to 1%, 1.2%, 1.5%, 2%, 5%, 8%, or 10% by weight.

[0058] As used herein, the term "polyol" refers to a compound having two or more hydroxyl groups. When a polyol has exactly two hydroxyl groups, it is a "diol," when it has exactly three hydroxyl groups, it is a "triol," when it has exactly four hydroxyl groups, it is a "tetraol," when it has exactly five hydroxyl groups, it is a "pentanol," and so on.

[0059] In some embodiments, one or more polyols in the polyol component have an average hydroxyl group functionality of 2 to 8, eg, 2 to 7, or 3 to 6.

[0060] In some embodiments, the one or more polyols included in the polyol component have an average number of hydroxyl groups of 25 mg KOH / g to 1000 mg KOH / g, e.g., 25 mg KOH / g to 900 mg KOH / g, 28 mg KOH / g to 1000 mg KOH / g, or 28 mg KOH / g to 900 mg KOH / g.

[0061] In some embodiments, the polyol component may include a polyester polyol. Compounds containing two or more ester bonds in the same linear atomic chain are referred to herein as "polyesters." Compounds that are both polyesters and polyols are referred to herein as "polyester polyols."

[0062] The polyester polyol employed in the polyurethane composition may have a molecular weight of no greater than 10,000 g / mol.

[0063] In some embodiments, the polyester polyol may have a hydroxyl group functionality of at least 2 (i.e., f ≥ 2). In some embodiments, the polyester polyol may have a hydroxyl group functionality of no more than 10 (i.e., f ≤ 10). In some embodiments, the polyester polyol may have a hydroxyl group functionality in the range of 2 to 8, 2 to 7, 3 to 7, 3 to 6, or 3 to 5.

[0064] In some embodiments, the polyester polyol may have a number of hydroxyl groups greater than 25 mg KOH / g. In some embodiments, the polyester polyol may have a number of hydroxyl groups less than 1,000 mg KOH / g. In some embodiments, the polyester polyol may have an average number of hydroxyl groups of 25 mg KOH / g to 950 mg KOH / g, 25 mg KOH / g to 900 mg KOH / g, 27 mg KOH / g to 1000 mg KOH / g, 27 mg KOH / g to 950 mg KOH / g, 28 mg KOH / g to 1000 mg KOH / g, or 28 mg KOH / g to 950 mg KOH / g.

[0065] In some embodiments, polyester polyols include but are not limited to diols and optional polyols (e.g., triols, tetraols) and dicarboxylic acids and optional polycarboxylic acids (e.g., tricarboxylic acids, tetracarboxylic acids) or hydroxycarboxylic acids or lactone condensation products. Polyester polyols can also be derived from corresponding polycarboxylic anhydrides or corresponding lower alcohol polycarboxylic acid esters, rather than free polycarboxylic acids.

[0066] Suitable diols include, but are not limited to, ethylene glycol, butanediol, diethylene glycol, triethylene glycol, pentanediol, hexanediol, polyalkylene glycols such as polyethylene glycol, and 1,2-propylene glycol, 1,3-propylene glycol, 1,3-butylene glycol, 1,4-butylene glycol, 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 more may be optionally included in the polyol composition (e.g., trimethylolpropane, glycerol, erythritol, pentaerythritol, trimethylolbenzene, or trishydroxyethyl isocyanurate).

[0067] Suitable dicarboxylic acids include, but are not limited to, aliphatic acids, aromatic acids, and combinations thereof. Examples of suitable aromatic acids include phthalic acid, isophthalic acid, terephthalic acid, and tetrahydrophthalic acid. Examples of 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 anhydride of the acid. In addition, monocarboxylic acids, such as benzoic acid and hexanecarboxylic acid, should be reduced or excluded from the disclosed composition as much as possible. Saturated aliphatic and / or aromatic acids are also suitable for the present disclosure, such as adipic acid or isophthalic acid.

[0068] In some embodiments, the polyol component may include a polyether polyol.

[0069] Compounds containing two or more ether bonds in the same linear chain of atoms are referred to herein as "polyethers." Compounds that are both polyethers and polyols are "polyether polyols."

[0070] The polyether polyol employed in the polyurethane composition may have a molecular weight of no greater than 10,000 g / mol.

[0071] In some embodiments, the polyether polyols may have a hydroxyl group functionality of at least 2 (i.e., f ≥ 2). In some embodiments, the polyether polyols may have a hydroxyl group functionality of no more than 10 (i.e., f ≤ 10). In some embodiments, the polyether polyols may have a hydroxyl group functionality in the range of 2 to 8, 2 to 7, 3 to 7, 3 to 6, 3 to 5.

[0072] In some embodiments, the polyether polyol may have a hydroxyl group number greater than 25 mg KOH / g. In some embodiments, the polyether polyol may have a hydroxyl group number less than 1,000 mg KOH / g. In some embodiments, the polyether polyol may have an average hydroxyl group number of 25 mg KOH / g to 950 mg KOH / g, 25 mg KOH / g to 900 mg KOH / g, 27 mg KOH / g to 1000 mg KOH / g, 27 mg KOH / g to 950 mg KOH / g, 28 mg KOH / g to 1000 mg KOH / g, or 28 mg KOH / g to 950 mg KOH / g.

[0073] In some embodiments, the polyether polyols used in the present disclosure are obtained by the addition polymerization of alkylene oxides with polyol starting compounds. Examples of such polyols include glycerol, sorbitol, sucrose, glucose, fructose, lactose or other sugars. In some embodiments, the starting compound is sorbitol or sucrose. These polyols and mixtures of these alcohols with water, glycerol, propylene glycol, ethylene glycol or diethylene glycol can be used as starting compounds. Examples of suitable sorbitol or sucrose / glycerol initiated polyethers that can be used include VORANOL TM 360、VORANOL TM RN411, VORANOL TM RN490、VORANOL TM 370、VORANOL TM 446. VORANOL TM 520, VORANOL TM 550、VORANOL TM RN 482, TERCAROL TM RF 55 or VORANOL TMRH 360 polyols, all of which are available from The Dow Chemical Company.

[0074] In some embodiments, the polyol component can have a viscosity at 25°C of 200 cSt to 38,000 cSt, eg, 200 cSt to 35,000 cSt, or 250 cSt to 35,000 cSt, as measured according to ASTM D2196.

[0075] (B) Isocyanate component

[0076] 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.

[0077] In some embodiments, the isocyanate component includes an SPE surfactant described herein. In some embodiments, the isocyanate component includes an SPE surfactant described herein in an amount of 0.01% to 10% by weight of the isocyanate component, for example, 0.01%, 0.05%, 0.1%, 0.5%, or 0.8% to 1%, 1.2%, 1.5%, 2%, 5%, 8%, or 10% by weight.

[0078] In some embodiments, the isocyanate compound may be one or more selected from isocyanate monomers, isocyanate prepolymers, modified isocyanates, and combinations thereof.

[0079] As used herein, an "isocyanate monomer" is any compound containing two or more isocyanate groups. An "aromatic isocyanate" is an isocyanate containing one or more aromatic rings. An "aliphatic isocyanate" does not contain aromatic rings. In some embodiments, the isocyanate compound comprises an aromatic isocyanate.

[0080] Isocyanate monomers suitable for use in 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 in accordance with the present disclosure include, but are not limited to, isomers of methylene diphenyl diisocyanate ("MDI"), such as 4,4-MDI, 2,4-MDI, and 2,2'-MDI, or modified MDI, such as carbodiimide-modified MDI or urethane-modified MDI or allophanate-modified MDI; isomers of toluene diisocyanate ("TDI"), such as 2,4-TDI, 2,6-TDI; isomers of naphthalene diisocyanate ("NDI"), such as 1,5-NDI; and combinations thereof. Examples of aliphatic isocyanates suitable for use according to the present disclosure include, but are not limited to, isomers of hexamethylene diisocyanate ("HDI"), isomers of isophorone diisocyanate ("IPDI"), isomers of xylene diisocyanate ("XDI"), isomers of methylene-bis-(4-cyclohexyl isocyanate) ("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-cyclohexyl isocyanate) (HMDI), hexamethylene diisocyanate (HDI), methylene diphenyl diisocyanate (MDI), toluene diisocyanate (TDI), and combinations thereof.

[0081] 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 may include aliphatic and cycloaliphatic isocyanates, but aromatic and especially polyfunctional aromatic isocyanates such as 2,4- and 2,6-toluene diisocyanate and corresponding isomer mixtures; 4,4'-, 2,4'- and 2,2'-diphenyl-methane diisocyanate (MDI) and corresponding isomer mixtures; 4,4'-, 2,4'- and 2,2'-diphenylmethane diisocyanate and polyphenyl polymethylene polyisocyanate (PMDI) mixtures; and mixtures of PMDI and toluene diisocyanate are preferred. Most preferably, the polyisocyanate used to prepare the prepolymer formulation of the present invention is MDI or PMDI or a crude mixture of any of these.

[0082] In some embodiments, the isocyanate component may have a viscosity of 50 to 20,000 mPa·s, 50 to 18,000 mPa·s, or 100 to 18,000 mPa·s at 25° C., as measured according to ASTM D2196.

[0083] In some embodiments, after storage for a duration of about 14 days at 25° C., or after accelerated aging for more than 5 days at 80° C., the amount of odor components generated by the polyol component and / or isocyanate component comprising a stabilized SPE surfactant is lower than the amount of odor components generated by the polyol component and / or isocyanate component comprising the same SPE surfactant but not stabilized according to the present disclosure (e.g., 30%, 40%, 50%, 60%, 70%, 80%, 90%, or 95% or more). The odor component can be one or more selected from aldehydes (e.g., propionaldehyde), cyclic ethers (e.g., trioxoctane, EMD, DMD), or mixtures thereof.

[0084] D. Polyurethane products

[0085] In another aspect, the present disclosure provides a polyurethane product formed using the polyurethane composition described above.

[0086] In some embodiments, the polyurethane product is a polyurethane foam.

[0087] Generally, polyurethane foams can be formed by: (i) providing a polyurethane composition as described comprising (A) a polyol component and (B) an isocyanate component; (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.

[0088] The (A) polyol component and the (B) isocyanate component are as described in "C. Polyurethane composition".

[0089] In some embodiments, the reaction mixture reacts, expands and cures in the enclosed space to form a polyurethane foam in the enclosed space. In some embodiments, the reaction mixture is reacted, expanded and cured at room temperature or higher.

[0090] In some embodiments, after storage for a duration of about 14 days at 25° C., or after accelerated aging for more than 5 days at 80° C., the amount of odor components produced by the polyurethane product made using the stabilized SPE surfactant is lower than the amount of odor components produced by the polyurethane product made using the same SPE surfactant but not stabilized according to the present disclosure (e.g., 30%, 40%, 50%, 60%, 70%, 80%, 90%, or 95% or more lower). The odor component can be one or more selected from aldehydes (e.g., propionaldehyde), cyclic ethers (e.g., trioxoctane, EMD, DMD), or mixtures thereof.

[0091] E. Uses and Applications

[0092] In another aspect, the present disclosure provides for use of a stable SPE surfactant described herein in the manufacture of a polyurethane composition.

[0093] In some embodiments, the polyurethane composition is a polyurethane foam composition.

[0094] In another aspect, the present disclosure provides for use of the stable SPE surfactants described herein in the manufacture of a polyurethane product.

[0095] In some embodiments, the polyurethane product is a polyurethane foam.

[0096] Example

[0097] Some embodiments of the present invention will now be described in the following examples, in which all parts and percentages are by weight unless otherwise indicated.

[0098] 1. Reagents and Chemicals

[0099]

[0100]

[0101] The structures of some of the exemplary pretreatment additives listed above are shown below.

[0102]

[0103] 2. Sample Preparation

[0104] 2.1 Preparation of formulated polyols for making foams

[0105] Detailed formulations are described in Examples CE10 and IE10.

[0106] a. The additives described above were first mixed with SPE surfactants or polyols based on the formulations in the Example Table below (see formulation below for each result).

[0107] b. The mixture of surfactant or polyol and additives was stored at 25°C overnight.

[0108] c. The above mixture was added together with other components and then mixed by a stirrer at a speed of 3000RPM for 3 minutes to obtain a formulated polyol as Part A. The formulated polyol was then stored at 25°C for 12-24 hours before foaming.

[0109] 2.2 Foaming procedure

[0110] An aliquot of 106.69 g of the formulated polyol was mixed with 58.4 g of TDI isocyanate to prepare the foam sample. After foaming, the foam sample was wrapped in aluminum foil. Air pocket analysis was performed within 7 days of preparing the foam sample.

[0111] 3. Quantification of Odor Enhancers in SPE Surfactants and Foams

[0112] 3.1 Sample preparation

[0113] Samples (0.3 g) were placed in 20 mL headspace GC-MS vials for analysis.

[0114] 3.2 SPME (Solid Phase Microextraction) GC-MS Method Parameters

[0115] SPME GC-MS analysis was performed on an Agilent 7890 gas chromatograph coupled to a mass spectrometer detector (Agilent 5975C MSD). GC conditions are listed below. Semi-quantification was performed by reference to standards (each 5 ppm, prepared in polyol 8010). The LOQ (limit of quantification or limit of detection) of the method for various cyclic ethers was about 0.01 ppm.

[0116] [Oven Program]

[0117] Initial temperature: 50℃ (open) Maximum temperature: 325℃

[0118] Initial time: 4.00 minutes Equilibrium time: 0.50 minutes

[0119] Gradient:

[0120] #Rate Final Temperature Final Time Low Temperature (N2)

[0121] 1 16 250 2 Low temperature: Off

[0122] 2 0.0 (off) Low temperature fault: off

[0123] Running time: 18.50 minutes Ambient temperature: 25°C

[0124] [SPME conditions]: PDMS / DVB SPME fiber from Supleco Co. Ltd

[0125] Incubation temperature: 75°C

[0126] Incubation time: 5.00 min

[0127] Extraction time: 30 minutes

[0128] [column]

[0129] Agilent 19091S-433, HP-5MS, 5% phenylmethylsiloxane, 30m×250μm, 0.25μm film thickness

[0130] Mode: Constant pressure

[0131] Pressure: 7.6522psi

[0132] Nominal initial flow rate: 1 ml / min

[0133] Average speed: 36.445 cm / s

[0134] [MS SCAN and SIM parameters]

[0135] DMD / EMD Quantification:

[0136] Resolution: Low

[0137] Group start time: 2.30

[0138] Curve 1 ion: 72.00

[0139] ion / stay in group (mass,stay)(mass,stay)(mass,stay)

[0140] (59.00,30)(72.00,30)(87.00,30)

[0141] Trioxane quantification:

[0142] Resolution: Low

[0143] Group start time: 8.00

[0144] Curve 1 ion: 101.00

[0145] ion / stay in group (mass,stay)(mass,stay)(mass,stay)

[0146] (59.00,30)(101.00,30)(130.00,30)

[0147] 4. Examples and Tests

[0148] 4.1 Comparison between commercial SPE and pretreated SPE

[0149] Testing of amine catalysts to validate their use on surfactants NIAX TM Silicone L-650 was pretreated to reduce the concept of cyclic ether formation during storage of the surfactant. Therefore, the surfactant was compared with 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 extended storage.

[0150] Thus, Comparative Example 1 (CE1), corresponding to a commercial SPE grade, showed significant formation of cyclic ethers after accelerated aging, with DMD levels increasing from 0.01 ppm at time zero to 0.11 ppm after 6 days at 80°C.

[0151] Comparative Example 2 (CE2), corresponding to a commercial SPE pretreated with water, showed similar cyclic ether formation to CE1 after aging. Of the three cyclic ethers, trioxoctane formation increased more rapidly during the initial portion of the test, reflecting the effect of the presence of water. SPE pretreated with antioxidant AO1135 (CE3) had some effect in reducing cyclic ether formation after aging, with lower levels of cyclic ethers compared to CE1, however the impact was limited and may not be sufficient to address odor issues.

[0152] The most significant effect on the formation of cyclic ethers after aging is with the amine catalyst Jeffcat TM The SPE pretreated with ZR50 is related to Example 1 (IE1) of the present invention, which shows that the amount of cyclic ethers hardly changes after accelerated aging at 80°C for 6 days.

[0153] Table 1. Cyclic ethers formed during storage

[0154]

[0155] 4.2 Comparison between commercial SPE and SPE pretreated with different amines

[0156] SPEs pretreated with different amines were evaluated and compared to commercial SPEs. Acetic acid, which is often observed in SPE surfactants (from acetaldehyde oxidation), was included in the pretreatment agent. Note that most of the amines used here are typical amine catalysts used in PU foam formulations.

[0157] In Table 2, CE4 corresponds to a commercial SPE and CE5 to a commercial SPE pretreated with water, these two examples therefore repeat the same compositions as those already mentioned in Table 1, differing now however in the type of ageing treatment (16 hours at 80°C) and in the type of test (headspace SMPE).

[0158] CE6 and CE7 correspond to SPE pretreated with acetic acid. The amount of degradation products produced after aging, and especially the amount of odor components such as propionaldehyde and cyclic ethers, increased significantly, indicating that pretreatment with acid will lead to a deterioration in the formation of odor components after SPE aging.

[0159] Embodiments IE2, IE3 and IE4 of the present invention correspond to the use of different levels of JEFFCAT TMSPE pre-treated with ZR-50 (with or without water). The results after accelerated aging showed a significant reduction in the amount of propionaldehyde detected.

[0160] Inventive Examples IE5, IE6, IE7 correspond to SPEs pretreated with other amines, again showing a significant reduction in the amount of propionaldehyde detected after accelerated aging compared to the comparative examples.

[0161] The samples were aged at 80° C. for 16 hours prior to testing. Despite the relatively short accelerated aging time, the benefits of using the inventive concept are demonstrated by the experimental data, which in this experiment was limited to propionaldehyde quantification.

[0162] Pre-treatment of the SPE with basic compounds, such as those considered in the present examples reported in Table 2, stabilizes the SPE such that the formation of odorous components during storage is significantly reduced.

[0163] Example IE4 is of particular interest 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 pre-treated with only 1% basic compound.

[0164] It should also be noted that typically, the formulated polyol will also contain an amine catalyst. However, these amine catalysts may not be very effective in stabilizing the SPE surfactant because most of the cyclic ether may have been formed during shipping and storage of the surfactant.

[0165] Table 2. Cyclic ethers and propionaldehydes formed during storage

[0166]

[0167] Remarks: For propanal, the results are reported as peak areas, as it was not possible to accurately perform a peak area to ppm conversion, it was decided to leave the results expressed in peak areas as they better reflect the concentration of the odor species in the samples.

[0168] 4.3 Unstabilized or Amine-Stabilized Commercial SPE: Polyols and Foam Testing

[0169] In previous examples, it has been shown that commercial SPEs can show degradation during storage, leading to the formation of odor components. It has also been shown that pre-treatment of the SPEs with a basic compound can significantly reduce the rate of degradation, thus resulting in pre-treated SPEs having a smaller content of odor components.

[0170] It has now been shown that the amount of odor degradation products present in the SPE can have a direct impact on the presence of odor components in the final PU foam.

[0171] Thus, Table 3 shows that after accelerated aging at 80°C for 10 days, the commercial SPE surfactants contain a large amount of propionaldehyde and a large amount of cyclic ethers (see CE8). When considering the same SPE surfactant pre-treated with a stabilizer (see IE8), these same odorous components are present in much smaller amounts.

[0172] Table 4 shows the amounts of propionaldehyde and cyclic ethers detected present in formulated polyols prepared using either the commercial SPE or the pretreated SPE described in Table 3. The data show that the greater amounts of propionaldehyde and cyclic ethers associated with the aged commercial SPE grades are reflected in proportionally greater amounts of the same odor components in the formulated polyols.

[0173] The formulated polyol samples were prepared as follows. The various formulation ingredients (see recipe below) were mixed with a stirrer at 3000 RPM for 3 minutes. Both formulated polyols were then stored at 25°C for about 2 days before testing for degradation products.

[0174] Table 5 shows the amounts of propionaldehyde and cyclic ethers detected present in PU foams made using the formulated polyols from Table 4. The data show that the greater amounts of propionaldehyde and cyclic ethers associated with aged commercial SPE grades are reflected in proportionally greater amounts of the same odor components in the final foam.

[0175] The foaming procedure was as follows. An aliquot of 106.69 g of the formulated polyol was mixed with 58.4 g of isocyanate 1 using a stirrer at 3000 RPM for 1 minute to prepare a foam sample. After foaming, the foam sample was wrapped in aluminum foil. Air bag analysis was performed 3 days after the foam sample was prepared.

[0176]

[0177]

[0178] Table 3. Cyclic ethers in commercial SPE or pre-treated SPE after aging

[0179]

[0180] Table 4. Cyclic ethers in formulated polyols containing aged commercial SPE or aged pretreated SPE

[0181]

[0182] Table 5. Preparation of polyols using formulated polyols containing aged commercial SPE or aged pre-treated SPE. Cyclic ethers in PU foam

[0183]

[0184] The data in Table 5 show that although the amount of SPE surfactant is only about 1% of the total PU foam mass, the mass of the SPE can have a significant impact on the amount of odor components present in the foam. The use of pretreated SPE surfactant allows the amount of odor components, especially trioxoctane, to be reduced.

[0185] Table 6. Stability of Niax L650 without pretreatment or pretreated with various basic compounds with different pKb Extended research

[0186]

[0187] Note: The data in Table 6 expand on the types of tests already described in Table 1. Specifically, samples were tested within 24 hours of sample preparation (freshly prepared) and analyzed after 2 weeks of storage at room temperature. The LOQ of the method is 0.01 ppm. Detection is limited to trioxoctane.

[0188] Various amines with different pKb were selected for this study. It was indicated that most amines showed similar behavior in inhibiting the degradation of unsaturation and the formation of trioxoctane. Too strong basicity showed a negative effect, such as KOH. A pKb of 2.8 to 5.0 showed the best performance. Higher pKb such as aniline and diphenylamine showed an effect, but not as good as others.

[0189] Table 7. Extended study of loading ratios of ZR-50 and Polyol 2

[0190]

[0191] Note: Samples were tested within 24 hours of sample preparation (freshly prepared) and analyzed after 2 weeks of storage at room temperature.

[0192] Polyol 2 and ZR-50 were selected to study the effect of loading ratio. For ZR-50, the inhibitory effect can be maintained up to 0.01%, although the effect decreases with lower loading ratios. Two tests using polyol 2 show that it also works because it contains a tertiary amino structure, but there is a difference in equivalent weight compared to ZR-50, which is about 10 times. Therefore, the wt% loading level of polyol 2 in the surfactant must be about 10 times that of ZR-50 to have a similar effect on stability. Amines with higher ratios cause better inhibitory performance, but it is necessary to balance performance and potential side effects from amines.

Claims

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

0.

2. The method of claim 1, wherein the amount of the alkaline compound used to pre-treat the SPE surfactant is 0.01 wt% to 15 wt% of the SPE surfactant.

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

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

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

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

7. The method of claim 1, wherein the pretreatment of the SPE surfactant with a basic compound having a pKb of 1.0 to 9.0 is performed after synthesizing the SPE surfactant.

8. A stable SPE surfactant obtained by the method according to claim 1.

9. 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; and (B) an isocyanate component, the isocyanate component comprising one or more isocyanate compounds, Wherein the (A) polyol component and / or the (B) isocyanate component comprises a stable SPE surfactant obtained by the method according to claim 1.

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

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