Reactive flame retardant blends for flexible polyurethane foams

Abstract

The invention provides a dialkyl phosphorus-containing compound, namely a reactive monohydroxy-functional dialkyl phosphinate, in a blend with a phosphate compound, which acts as a highly effective reactive flame-retardant blend in flexible polyurethane foams. The invention further provides a flame-retardant polyurethane composition comprising the reaction product of the flame-retardant blend with a polyol and isocyanate foam-forming components.

Description

[0001] This application claims the benefit of U.S. Provisional Patent Application No. 62 / 561,365, filed September 21, 2017, the entire contents of which are incorporated herein by reference. Technical Field

[0002] This disclosure provides the use of reactive dialkyl phosphorus compounds (i.e., hydroxyl-functionalized dialkylphosphine esters) that, when reacted with polyols and isocyanates, act as highly effective reactive flame retardants in flexible polyurethane foams. The invention further provides flame-retardant flexible polyurethane foams having said hydroxyl-functionalized dialkylphosphine esters, which are reacted and incorporated into the polymer matrix of the flexible polyurethane foam. The terms "flame retardant" and "fire retarder" are used interchangeably herein. Background Technology

[0003] It is known that brominated or phosphorus-based flame retardants are highly effective and, in many cases, the only option for reducing the fire risk of synthetic materials such as flexible polyurethane foam. However, over the years, there has been increasing (growing) public and governmental oversight of chemicals, particularly flame retardants. The goal is towards more sustainable, reactive, polymeric, and / or halogen-free new products. Oversight is significantly reduced if flame retardants are reacted and incorporated into the polymer matrix and cannot be leached out.

[0004] Therefore, there is a demand for reactive phosphorus-containing fire retardants for flexible polyurethanes that possess characteristics such as high phosphorus content, transparent light color, and good compatibility with polyether polyols and polyester polyols used in the polyurethane industry. Summary of the Invention

[0005] This invention provides a flame-retardant blend comprising (1) a reactive dialkylphosphine-containing monohydroxy functional compound and (2) a phosphate ester compound, said flame-retardant blend possessing highly satisfactory flame-retardant properties and good compatibility with the polyol component in a flexible polyurethane foam forming system. It should be understood that, as used herein, the term "flexible polyurethane foam forming system" includes polyols, isocyanates, and flame-retardant blends as described herein. The monohydroxy functional dialkylphosphine ester compound is sufficiently reactive by its monohydroxy functional group and is easier to formulate than di- or tri-hydroxy functional dialkylphosphine ester compounds. It has been unexpectedly found that the reactive monohydroxy functional dialkylphosphine ester compound described herein, despite its lower hydroxyl functional group content, can react and be incorporated into the polymer structure of the flexible polyurethane foam, for example, by reacting with the isocyanate component of the flexible polyurethane foam forming system, without compromising the elasticity of the flexible polyurethane foam. This means that the flame retardants of the present invention are integrated into the flexible foam matrix, making them unlikely to be released into the environment and unlikely to penetrate through living tissue cell membranes, thus posing no health hazard. The present invention further provides the above-described flexible polyurethane foam forming system, which includes, but is not limited to, the reactive dialkyl phosphorus-containing monohydroxy functional compounds described herein.

[0006] The applicant has discovered an unexpected synergistic relationship between the monohydroxy-functional dialkylphosphines described herein and phosphate compounds, such as phosphate esters. These phosphines / phosphate ester blends contain less phosphorus than the monohydroxy-functional dialkylphosphines alone, yet retain the same flame retardant efficacy. The applicant has further discovered that this synergy extends to a wide variety of phosphate ester products that can be combined with monohydroxy-functional dialkylphosphines.

[0007] In addition to maintaining high levels of flame retardant performance through these synergistic flame-retardant blends, the applicant has discovered an unexpected improvement: the physical properties (e.g., compression set) of the resulting foam are significantly improved compared to those observed when using monohydroxy-functional dialkylphosphinate compounds alone. It is known in the art that reactive flame retardant products disrupt the normal foaming process, resulting in poor foam physical properties. In most cases, this is observed through a loss of the foam's resilience after compression at elevated temperatures. Compression set testing according to ASTM D3574 is a standard requirement for foams and ensures that compressed foam does indeed spring back. By using a small amount of monohydroxy-functional dialkylphosphinate compounds in the phosphinate / phosphate flame-retardant blends, the negative effects of using reactive flame retardant products are avoided, while still retaining the high flame retardant efficacy required in end-use products. The flame-retardant blends unexpectedly retain both excellent FR performance and good physical properties.

[0008] As used herein, the term "foam" refers to flexible polyurethane foam. Flexible polyurethane foam described herein (or claimed herein) that comprises, is substantially composed of, or is composed of, a group consisting of a group of reacted monohydroxy-functional dialkylphosphinate compounds, phosphate compounds, and partially phosphorylated (phosphorylated) phosphoroyl diols and / or polyols of general formula (IA) and / or (IB), is understood herein to contain the foregoing formula as a reactive material, i.e., the foregoing formula reacts into the structure of the flexible polyurethane material, in which case the foregoing formula may not or will not exist in the same structural form as described herein, but will exist in the flexible polyurethane material as a reaction product of diols and / or polyols, isocyanates, and the structural form described herein.

[0009] It will be understood that the term "polyol" as used herein may also be defined as diols and / or polyols.

[0010] The flame-retardant blends of the present invention provide a group consisting of (A) a monohydroxy-functional dialkylphosphinate compound of general formula (IA) and (IB), and a partially phosphorylated phosphorodiol and / or polyol reaction product of general formula (IB) comprising at least one phosphorus-containing group, and (B) a phosphate ester compound, wherein formula (IA) is:

[0011]

[0012] in:

[0013] R 1 and R 2Selected from linear or branched alkyl groups containing 1 to 4 carbon atoms, such as methyl, ethyl, propyl, isopropyl, butyl, and isobutyl, preferably methyl or ethyl, more preferably R. 1 and R 2 Both are ethyl; and,

[0014] X is and

[0015] When X is When Z is –(Y–O) n – where Y is a linear or branched alkylene group containing 2 to 8 carbon atoms, preferably 2 to 4 carbon atoms, more preferably ethylene, propylene, or isopropylene, and n represents an integer from 1 to 20, preferably 1 to 5, and even more preferably 1 to 2.

[0016] k can be 0 or 1;

[0017] R 3 Selected from hydrogen, linear or branched alkylene groups with monohydroxyl-terminated ends comprising 2 to 8 carbon atoms, preferably 2 to 4 carbon atoms; and,

[0018] The premise is that when k is zero, R 3 R is a linear or branched alkylene group capped with a single hydroxyl group, and when k is 1, R 3 For hydrogen, and when X is At that time, R 4 and R 5 Each is independently selected from H, a linear or branched alkyl group comprising 1 to 8 carbon atoms, preferably 1 to 4 carbon atoms, and most preferably any one of methyl, ethyl, or propyl; a linear or branched alkenyl group comprising 2 to 8 carbon atoms, preferably 2 to 4 carbon atoms; a halogen-substituted alkyl group comprising 1 to 8 carbon atoms; an alkoxy group comprising 1 to 8 carbon atoms, preferably 1 to 4 carbon atoms; an aryl group comprising 6 to 12 carbon atoms, preferably 6 to 8 carbon atoms; and an alkylaryl group comprising 7 to 16 carbon atoms, preferably 7 to 12 carbon atoms, or R 4 and R 5 They bond to each other to form cycloalkyl groups containing 4 to 8 carbon atoms, preferably 6 carbon atoms; and wherein the formula (IB) is:

[0019]

[0020] in:

[0021] R 1 and R 2 Independently selected from linear or branched alkyl groups containing 1 to 4 carbon atoms, such as methyl, ethyl, propyl, isopropyl, butyl, and isobutyl, preferably methyl or ethyl, more preferably R. 1 and R 2Both are ethyl; and,

[0022] n 1 n is an integer equal to or greater than 1 and n 2 For one, the preferred value is n. 1 From about 1 to about 5, and

[0023] Z 2 For compounds derived from diols or polyols with a oxidation state of n 1 +n 2 Part of it and has the following general formula:

[0024]

[0025] Where R is selected from:

[0026]

[0027] and each of the R 6 Independently, it is H or an alkyl group with 1 to 4 carbon atoms, x is 0 or ≥1, preferably 1 to 4, more preferably x = 1, y is 2 or 3; z is an integer from 2 to 5; and m ≥ 1, preferably m = 1.

[0028] This article also provides methods for preparing these compounds.

[0029] The compound of formula (IA) can be prepared by reacting a monohydroxy functional dialkylphosphine acid of formula (II) with a compound having an oxacyclopropane group, wherein formula (II) is:

[0030]

[0031] Where R 1 and R 2 As defined.

[0032] Compounds of formula (IA) can also be prepared by reacting a dialkylphosphine halide of formula (III) with an aliphatic diol, wherein formula (III) is:

[0033]

[0034] and R 1 and R 2 As defined, and A is chlorine or bromine.

[0035] The phosphorus-containing diols and / or polyols of the present invention, such as those of formula IB, can be prepared by reacting the dialkylphosphine halide of formula (III) with aliphatic diols and / or polyols.

[0036] The reactive monohydroxy functional dialkylphosphinate of the present invention has a high phosphorus content, good hydrolytic and thermal stability, exhibits good compatibility with diol and / or polyol components in flexible polyurethane foam forming systems, and can be used as a highly efficient reactive flame retardant in flexible polyurethane foam.

[0037] The present invention further provides a flame-retardant flexible polyurethane comprising reactive residues after the phosphorus-containing monohydroxy functionalized compound and the phosphate ester compound have reacted in a flexible polyurethane foam forming system to form a flexible polyurethane foam. The phosphorus-containing monohydroxy functionalized compound described herein may be used alone or in premixes with each other and / or with other flame retardants (including halogenated and phosphorus-containing flame retardants) in the flexible polyurethane foam forming system.

[0038] All the above and other features and advantages of the present invention will be better understood by the following illustrative and non-limiting detailed description of its preferred embodiments. Attached Figure Description

[0039] Figure 1 This is a diagram illustrating the first set of data in Application Example 4, namely the RPE / BPPE blend.

[0040] Figure 2 This is a diagram illustrating the second set of data from Application Example 4, namely the RPE / BDP blend. Detailed Implementation

[0041] In one embodiment, the monohydroxy-functional dialkylphosphinate of formula (IA) may be more specifically those of formula (IA-1) or (IA-2), wherein formula (IA-1) is:

[0042]

[0043] Where R 1 and R 2 Z, k and R 3 As defined above; and,

[0044] Equation (IA-2) is:

[0045]

[0046] and R 1 R 2 R 4 and R 5 As defined above.

[0047] In one embodiment of this document, the monohydroxy-functional dialkylphosphinate of formula (IA) of the present invention is prepared by reacting a dialkylphosphine acid of formula (II) with a compound of formula (IV) having an oxacyclopropane group, wherein formula (IV) is

[0048]

[0049] in:

[0050] R 4 and R 5 As defined above.

[0051] In another embodiment of this document, the monohydroxy-functional dialkylphosphinate of formula (IA) of the present invention is prepared by reacting a dialkylphosphinoyl halide of formula (III) with an aliphatic diol of formula (V):

[0052] HO-(Z) K -R 3 (V)

[0053] Among them, Z and R 3 The subscript k is defined as above.

[0054] The phosphorus-containing diols and / or polyols of the present invention, such as those of formula (IB), are prepared by reacting a dialkylphosphine halide of formula (III) with an aliphatic diol or polyol.

[0055] The dialkylphosphonic acid (II) and dialkylphosphonic halogen (III) used as initial materials in the method of this invention are mostly known in the art. Compounds of formula (II) can be obtained, for example, by hydrolysis of the corresponding dialkylphosphonic halogen (III). The latter can be prepared, for example, by the method described in U.S. Patent No. 3,104,259, the entire contents of which are incorporated herein by reference.

[0056] The specific oxacyclopropane compound used in the method for preparing the compounds of formula (IA) or more particularly (IA-1) or (IA-2) of the present invention is selected from, but not limited to, ethylene oxide, propylene oxide, 1,2-epoxybutane, 1,2-epoxypentane, 1,2-epoxyhexane, 1,2-epoxy-5-hexene, 1,2-epoxy-2-methylpropane, 1,2-epoxyoctane, glycidyl methyl ether, glycidyl isopropyl ether, glycidyl isobutyl ether, glycidyl heptayl ether, glycidyl 2-ethylhexyl ether, glycidyl allyl ether, trimethylolpropane triglycidyl ether, styrene oxide, cyclohexene oxide, epichlorohydrin, and combinations thereof. More preferably, ethylene oxide, propylene oxide, and 1,2-epoxybutane are used as the oxacyclopropane compound.

[0057] The specific aliphatic diol used in the method for preparing compounds of formula (IA) or more particularly (IA-1) or (IA-2) of the present invention is selected from, but not limited to, ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol, 1,3-propanediol, 1,4-butanediol, 2-buten-1,4-diol, 1,5-pentanediol, 1,6-hexanediol, 1,8-octanediol, and other diols with a molecular weight of up to 700.

[0058] The aliphatic diols and / or polyols used in the method for preparing the phosphorus-containing polyols of the present invention can generally be any suitable diols and / or polyols having at least two or at least three reactive hydrogen atoms, examples being those having a functionality of 2 or 3 to 6 (preferably 2, 3 and 4) and a molecular weight preferably from about 100 to about 700. Specific aliphatic diols and / or polyols can be selected from non-polymeric polyols such as trimethylolpropane, trimethylolethane, or glycerol.

[0059] Preferably, the diols and / or polyols used according to the present invention are polyether diols and / or polyols. These diols and / or polyols are obtained by ring-opening addition reactions of one or more epoxides (e.g., ethylene oxide and propylene oxide) with suitable reactants (e.g., alcohols, amines, and acids) containing one or more active hydrogen atoms; more particularly, the reactants may be selected from diols, triols, phenolic resins, pentaerythritol, sorbitol, sucrose, diethylenetriamine, etc. Polyester polyols may also be used according to the present invention; these polyols are obtained by condensation reactions of carboxylic acids, dicarboxylic acids (or polycarboxylic acids) (e.g., adipic acid, phthalic acid, etc.) with diols or triols. The aliphatic diols and / or polyols used in the methods for preparing the phosphorus-containing monools, diols, or polyols of the present invention are selected from polymeric diols and / or polyols such as polyether polyols, polyester polyols, and mixtures thereof.

[0060] In a preferred embodiment of the invention, the reaction of dialkylphosphonic acid (II) with an oxacyclopropane compound takes place in an excess of oxacyclopropane medium in the presence or absence of an organic solvent such as tetrahydrofuran, 1,4-di(II) ... This is carried out in the case of alkyl or toluene.

[0061] The amount of oxopropane compound used in the reaction with monohydroxydialkylphosphonic acid (II) is 5-300% molar excess relative to monohydroxydialkylphosphonic acid, and preferably 50-100% molar excess. Using oxopropane compound in greater than 100% molar excess relative to monohydroxydialkylphosphonic acid is not advisable due to the need to recover large amounts of oxopropane.

[0062] Depending on the dialkylphosphonic acid and oxacyclopropane involved in the reaction, the monohydroxy functional dialkylphosphonates of formula (IA) or more particularly (IA-1) or (IA-2) of the present invention have a phosphorus content of about 8-18% by weight and a hydroxyl value of about 150-315 mg KOH / g.

[0063] For the preparation of a target monohydroxy functional dialkylphosphonate (IA) or more particularly (IA-1) or (IA-2) with the highest possible phosphorus content, it is preferred to react the monohydroxy-dialkylphosphonic acid (II) with ethylene oxide and propylene oxide.

[0064] Therefore, compounds of formula (IA) or more particularly (IA-1) or (IA-2) with particularly valuable properties are those in which R 1 and R 2 Those that are each ethyl.

[0065] The reaction is carried out at a temperature between 40°C and 120°C, and preferably between 70°C and 90°C. Below 40°C, the reaction becomes unacceptably slow. On the other hand, applying temperatures above 120°C is not recommended, as undesirable decomposition products can form at such temperatures.

[0066] In a preferred embodiment, the reaction of dialkylphosphinohydride (III) with aliphatic diol is carried out in a medium with excess diol.

[0067] The amount of diol compound used in the reaction with dialkylphosphinic halides (III) is typically 2 to 10 moles per mole of dialkylphosphinic halide, and preferably 4 to 8 moles in molar excess. A relatively large excess of the diol is required to minimize the formation of undesirable glycols and hydroxyl-free bis(dialkylphosphinic esters) of the diol. Using a molar excess of more than 10 moles per mole of dialkylphosphinic halide is not advisable due to the need to recover large amounts of diol.

[0068] Depending on the dialkylphosphinic halogen and diol involved in the reaction, the monohydroxy functional dialkylphosphinic esters of formula (IA) or more particularly (IA-1) or (IA-2) of the present invention have a phosphorus content of about 2-18% by weight and a hydroxyl value of about 150-450 mg KOH / g.

[0069] For the preparation of a target monohydroxy functional dialkylphosphonate (IA) or more particularly (IA-1) or (IA-2) with the highest possible phosphorus content, it is preferred to react the dialkylphosphonic halide (III) with the highest phosphorus content with ethylene glycol.

[0070] Therefore, the compound of formula (IA-1) with particularly valuable properties is R. 1 and R 2 Each is an ethyl group, k is 1, n is 1, Y is –CH2CH2–, and R 3 Compounds containing hydrogen.

[0071] The reaction is carried out at temperatures between 25°C and 120°C, and preferably between 50°C and 90°C. Applying temperatures below 25°C results in low yields. On the other hand, applying temperatures above 120°C is not recommended because undesirable decomposition products can form at such temperatures. Additionally, catalysts such as MgCl2 or ZnCl2 can be used to accelerate the reaction.

[0072] In a preferred embodiment, the reaction of dialkylphosphine halide (III) with an aliphatic diol is carried out in the presence of a strong base, such as sodium hydroxide or potassium hydroxide, in a medium containing both an organic solvent and an excess of the aliphatic alcohol. The organic solvent is selected from aromatic compounds. Particularly suitable aromatic solvents are chlorobenzene, o-dichlorobenzene, mesitylene, and especially toluene and xylene. The effective amount of base used in the method is in the range of 1-1.2 mol per mol of dialkylphosphine halide (III), and preferably 1-1.05 mol.

[0073] Sodium or potassium hydroxide may be used in solid form. Water produced by the reaction between the diol and the base should be removed from the reaction mixture as much as possible before the addition of the dialkylphosphinohydride (III).

[0074] In a preferred embodiment, the reaction of the dialkylphosphinohalide (III) with the aliphatic diol and / or polyol is carried out by altering the degree of partial phosphorylation of the diol and / or polyol. The phosphorus-containing diol and / or polyol according to the invention comprises at least one phosphorus-containing group. This phosphorus-containing group is a group of formula (III-A):

[0075]

[0076] in:

[0077] Where R 1 and R 2 As defined, and where the wavy line represents the bond between the oxygen atom and the diol or polyol.

[0078] The phosphorus-containing diols and / or polyols of the present invention may further include two or more phosphorus-containing groups of formula (III-A), wherein these phosphorus-containing groups may be the same or different.

[0079] The reaction of dialkylphosphinohydride (III) with aliphatic diols and / or polyols can be carried out in the presence of an organic base selected from, but not limited to, tertiary amines such as triethylamine, pyridine, diisopropylethylamine, and 1-methylimidazole. The amount of base used is equimolar with that of the dialkylphosphinohydride (III). The base may also be used in excess relative to the dialkylphosphinohydride. The reaction is typically carried out in an inert organic solvent medium. Suitable solvents for phosphorylation are, but not limited to, halogenated hydrocarbons such as dichloromethane, chloroform, or 1,2-dichloroethane. Other suitable solvents are ethers such as diethylphosphinohydride. Alkanes or tetrahydrofurans. Other suitable solvents are hydrocarbons such as hexane or toluene.

[0080] In a preferred embodiment, the reaction of dialkylphosphinohalides (III) with aliphatic diols and / or polyols is carried out in the presence of a strong inorganic base, such as sodium hydroxide or potassium hydroxide, in an organic solvent, such as chlorobenzene, mesitylene, and particularly toluene and xylene.

[0081] The effective amount of the base used in the method is in the range of 1-1.2 mol, and preferably 1-1.05 mol, per mol of dialkylphosphinohydride(III). Sodium hydroxide or potassium hydroxide may be used in solid form. Water produced by the reaction between the diol and / or polyol and the base should be removed from the reaction mixture as much as possible before the addition of the dialkylphosphinohydride(III).

[0082] The amounts of dialkylphosphine halide (III) and diols and / or polyols can be adjusted to achieve the desired degree of functionalization. Partial phosphorylation of the diols and / or polyols can be achieved by using a less-than-stoichiometric amount of dialkylphosphine halide (III) to the diol and / or polyol based on its functionality. In this manner, only a portion of the OH groups in the diol and / or polyol reacts with the dialkylphosphine halide.

[0083] The phosphorus-containing diols and / or polyols of the present invention (also referred to herein as partially phosphorylated diols and / or polyols) have a residual average OH- functionality of 1 (after its phosphorylation) and a molecular weight of about 200 to about 1000. Depending on the dialkylphosphinohydride and diol and / or polyol involved in the reaction and the molar ratio thereto, the phosphorus-containing diols and / or polyols of the present invention have a phosphorus content of about 4-20% by weight and a hydroxyl value of about 20-800 mg KOH / g.

[0084] The phosphorylation of diols and / or polyols is carried out at temperatures between 0°C and 100°C, and preferably between 10°C and 90°C. Applying temperatures below 0°C results in a low reaction rate. On the other hand, applying temperatures above 100°C is not recommended, as undesirable decomposition products can form at such temperatures.

[0085] The monohydroxy-functional dialkylphosphinate compounds of the present invention can be used as reactive flame retardants. These flame retardants can be used in blends with phosphate compounds as described herein and optionally additional halogenated or non-halogenated products. Some examples of halogenated flame retardants that can be used as phosphate compounds or additionally (wherein these are understood to be distinct) are chlorinated phosphates, such as the non-limiting example of tris(1,3-dichloro-2-propyl) phosphate (TDCP), and chlorinated diphosphates, such as CR-504L [phosphate, oxydi-2,1-ethanediyltetra(2-chloro-1-methylethyl) ester] (CAS#s 52186-00-2&184530-92-5) available from Daihachi, Amgard V6, and Yoke's ELF-800 (a propylene oxide analog of Amgard V6). For flexible polyurethane foams, the halogen-free hydroxyl-functional dialkylphosphinates of the present invention are preferred for use with halogen-free phosphate ester compounds.

[0086] The phosphate ester component (phosphate ester compound) in this document may be any phosphate ester, wherein the phosphate ester is selected from aliphatic phosphate esters, aromatic phosphate esters, mixed aromatic aliphatic phosphate esters, aliphatic bisphosphate esters, aromatic bisphosphate esters, mixed aliphatic aromatic bisphosphate esters, oligomeric phosphate esters, polymeric phosphate esters, and combinations thereof. In one embodiment, the aliphatic portion may be any one of alkyl, alkenyl, and alkynyl groups having up to 20 carbon atoms, preferably up to 12 carbon atoms, and most preferably up to 8 carbon atoms. In another embodiment, the aryl portion may comprise 6 to 20 carbon atoms, 6 to 12 carbon atoms, and 6 to 8 carbon atoms.

[0087] In one non-limiting embodiment, the phosphate ester has the general formula (VI):

[0088]

[0089] Where R 7 R 8 and R 9 Each of the following is independently a phenyl, an alkyl-substituted phenyl, or a linear or branched or saturated or unsaturated alkyl group containing up to 22 carbon atoms, more particularly a linear or branched or saturated or unsaturated alkyl group containing up to 6 carbon atoms, or a phenyl, or an alkyl-substituted phenyl group containing 6 to about 22 carbon atoms, even more particularly 6 to 12 carbon atoms, or a linear or branched alkoxy group containing up to 8 carbon atoms (preferably up to 6 carbon atoms); R is a divalent alkylene group containing 1 to 3 carbon atoms, and subscripts a, b, and c are each 0 or 1, and when any of a, b, and c is 1, each R bonded to it is... 7 R 8 and R 9It is a linear or branched alkoxy group containing up to 8 carbon atoms, preferably up to 4 carbon atoms.

[0090] Suitable examples of trialkyl phosphates are triethyl phosphate, tripropyl phosphate, triisopropyl phosphate, tributyl phosphate, tritert-butyl phosphate, tri(2-ethylhexyl) phosphate, trioctyl phosphate, and combinations thereof.

[0091] Some examples of phosphate alkoxy esters are tris(2-butoxyethyl) phosphate, tris(2-methoxyethyl) phosphate, tris(2-ethoxyethyl) phosphate, tris(2-isopropoxyethyl) phosphate, tris(2-hexyloxyethyl) phosphate, and combinations thereof.

[0092] In another embodiment described herein, the phosphate ester has the general formula (VII).

[0093]

[0094] Where (i)R 8 and R 9 Only one of them is a linear or branched or saturated or unsaturated alkyl group containing at most 22 carbon atoms, more particularly 6 to 22 carbon atoms, and most particularly 4 to 12 carbon atoms, and the remaining R 8 Or R 9 Partially unsubstituted or aryl groups of 6 to 10 carbon atoms substituted with 1 to 4 carbon atoms, or (ii) R 8 and R 9 Both are linear or branched, saturated or unsaturated alkyl groups containing up to 22 carbon atoms, more particularly 6 to 22 carbon atoms, and most particularly 4 to 12 carbon atoms.

[0095] In one embodiment of this document, the phosphate ester may be selected from diethylphenyl phosphate, ethyl diphenyl phosphate, di-n-propylphenyl phosphate, di-n-butylphenyl phosphate, di-n-butyldiphenyl phosphate, diisobutylphenyl phosphate, isobutyldiphenyl phosphate, di-n-pentylphenyl phosphate, di-n-pentyldiphenyl phosphate, di-n-hexylphenyl phosphate, 2-ethylhexyldiphenyl phosphate, isodecyldiphenyl phosphate, and mixtures thereof.

[0096] In one specific embodiment of this document, the phosphate ester is an aromatic phosphate ester compound, preferably an aromatic phosphate ester containing three aryl moieties or a bisphosphate ester containing four aryl moieties.

[0097] Examples of commercially available phosphate esters that may be used in this article are triaryl phosphate esters, such as those selected from the following: triphenyl phosphate, trimethyl phosphate, mixed phenyl-tolyl phosphate, tridimethyl phosphate, mixed phenyl-tolyl phosphate, trimethylbenzene phosphate, mixed betaine phosphate, tri(propylphenyl) phosphate, mixed propylphenylphenyl phosphate, tri(isopropylphenyl) phosphate, mixed isopropylphenyl-phenyl phosphate, tri(butylphenyl) phosphate, mixed butylphenylphenyl phosphate, tri(isobutylphenyl) phosphate, mixed isobutyl-phenylphenyl phosphate, tri(tert-butylphenyl) phosphate, mixed tert-butylphenylphenyl phosphate, and combinations thereof.

[0098] In yet another embodiment of this document, the phosphate ester has the general formula (VIII):

[0099]

[0100] Where X is C2-C 30 Dihydroxy compounds or C6-C 30 The residues of dihydroxyaryl compounds, R 10 R 11 R 12 and R 13 Each is independently C1-C8 alkyl, C3-C8 cycloalkyl, or C6-C 20 Aryl, and the subscript n is the average oligomer value from 1 to 10.

[0101] In the above formula (VIII) of the aromatic phosphate ester, the subscript n is preferably 1 to 3, and more preferably 1, X is a residue of an aromatic dihydroxy compound such as hydroquinone, resorcinol, bis(4-hydroxydiphenyl)methane, bisphenol A, dihydroxybiphenyl, dihydroxynaphthalene, bis(4-hydroxyphenyl)sulfone, bis(4-hydroxyphenyl)ketone, and bis(4-hydroxyphenyl)sulfide, and preferably a residue of hydroquinone, resorcinol, or bisphenol A, and R 10 R 11 R 12 R 13 Each residue is an aromatic monohydroxy compound such as phenol, cresol, xylenol, isopropylphenol, butylphenol, and p-cumylphenol, and preferably each residue is an aromatic monohydroxy compound such as phenol, cresol, or xylenol.

[0102] Furthermore, the phosphate ester component in this article is an aromatic bisphosphate, including those selected from: hydroquinone bis(diphenyl phosphate), resorcinol bis(diphenyl phosphate) (…). RDP, ICL-IP America, Tarrytown, NY), Bisphenol A bis(diphenyl phosphate) ( BDP, ICL-IP America, Tarrytown, NY), neopentyl glycol bis(diphenyl phosphate), propylene glycol bis(diphenyl phosphate), and combinations thereof. Among these phosphate esters, resorcinol bis(diphenyl phosphate) and bisphenol A bis(diphenyl phosphate), and combinations thereof, are the most preferred.

[0103] The flame retardant blends described herein will contain 25-95% by weight of phosphate esters, particularly 50%-90% by weight of phosphate esters, and more particularly 70-90% by weight of phosphate esters, based on the total weight of the flame retardant blends.

[0104] The phosphate esters described herein can be prepared by any of several known and conventional methods. For example, aromatic phosphate esters can be prepared by reacting phosphorus oxychloride with an aromatic dihydroxy compound (such as any of the aforementioned) in the presence of a Lewis acid catalyst (such as aluminum chloride, magnesium chloride, or titanium tetrachloride), removing unreacted phosphorus oxychloride from the resulting reaction mixture, and then reacting the latter with an aromatic monohydroxy compound (such as any of the aforementioned) to provide an aromatic phosphate ester. In a variant of this method, aromatic phosphate esters are obtained by reacting phosphorus oxychloride with a mixture of an aromatic monohydroxy compound and an aromatic dihydroxy compound.

[0105] In one embodiment, the flame-retardant blend as described herein is provided by blending a hydroxyl-functionalized dialkylphosphine ester and a phosphate ester component with a reactive brominated product containing hydroxyl groups. For flexible PU foams as described herein, it is preferred to use the pure, halogen-free hydroxyl-functionalized dialkylphosphine ester of the present invention with the phosphate ester compound.

[0106] The monohydroxy-functional dialkylphosphinate compounds of this invention are highly effective reactive flame retardants when introduced into flexible polyurethane foams together with phosphate ester compounds. It should be noted that the flame retardant blends of this invention can be used within a wide range of isocyanate indices (abbreviated herein as MDI or TDI). This index refers to the percentage of the stoichiometric amount of isocyanate actually used in the formulation relative to the theoretically required isocyanate.

[0107] The flexible polyurethane foam described herein comprises a typical effective amount of the flame retardant blend of the present invention. Typically, the flame retardant blend of the present invention is applied in an amount providing a total phosphorus concentration in the polymer (i.e., the flexible polyurethane foam) ranging from 0.3 to 15 wt% based on the total weight of said polymer. Preferably, the total phosphorus concentration in said polymer is in the range of 1 to 10 wt%, and more preferably in the range of 1.5 to 5 wt%, based on the total weight of the flexible polyurethane polymer. Most preferably, the amount of the flame retardant blend of the present invention is sufficient at least to meet the current requirements of the flammability test method MVSS 302.

[0108] Flexible polyurethane foams, varying in their degree of flexibility, can be manufactured by appropriately selecting components and conditions. Therefore, flexible foams typically use water as the primary blowing agent and are made from polymeric diols or triols with hydroxyl values ​​of 20-80.

[0109] The flexible polyurethane foam of the present invention may contain appropriately selected additives such as catalysts, surfactants, foam stabilizers, etc.

[0110] The flexible polyurethane foam used herein is made using diols and / or polyols having a molecular weight of 3,000 to about 6,000, such as diols and / or polyols described herein, for example, polyether triols prepared by adding propylene oxide to glycerol. The flexible polyurethane foam used herein is characterized by having a core impact resilience of up to 30% and a glass transition point of -80°C to -60°C. Here, the flexible polyurethane foam preferably has a hard segment content of up to 40% by mass. Conventional flexible polyurethane foams have a bulk density of 2.5 lb / cm³ (PCF) or less and a density of 10-90 lb / 50 in. 2 Foam hardness or IFD within the range (measured according to test method ASTM 3574-Test B1).

[0111] The method for manufacturing flexible polyurethane foam of the present invention may include combining one or more of the diol and / or polyol components and / or the isocyanate components or catalysts and flame retardant materials of formulas (IA), (IA-1), (IA-2) and (IB) and the phosphate ester compounds described herein (which can be metered and pumped into a conventional mixing container), and then the resulting mixture can be readily moved to a polymerization site for use in molds, sheet operations, etc.

[0112] The reactive flame retardant and the phosphate compound of the present invention may also be premixed with a diol and / or polyol reactant before being combined with the isocyanate reactant. Mixing the reactive flame retardant material and the phosphate compound with the isocyanate, and then combining such a mixture with the diol and / or polyol reactant, is also within the scope of the present invention. However, if the isocyanate and the aforementioned flame retardant material are mixed and allowed to stand at room temperature for a substantial period of time, a reaction may occur. In one embodiment, the term "reaction product," as used in the claims and this specification, may include reacting the contents of a flexible polyurethane foam forming system in any of the aforementioned methods, and may further include reacting the reactive flame retardant via a prepolymer technique, for example, reacting an excess of isocyanate with a polyol to form an isocyanate-terminated prepolymer, and then further reacting the prepolymer with the reactive flame retardant and phosphate compound described herein.

[0113] The flame retardant materials of formulas (IA), (IA-1), (IA-2) and (IB) described in this article can be referred to as isocyanate-reactive (NCO-reactive) materials, that is, they can react with isocyanates through hydroxyl groups.

[0114] The diols and / or polyols used in the manufacture of the flexible polyurethane foams described herein may include any organic polyols (including diols, polyols), and polyether, polyester, and polyesteramide polyols having hydrogen atoms that can react with isocyanates may be used. Typically, these materials have a molecular weight ranging from about 62 to about 5,000 and have 2 to about 10 or more hydroxyl groups per molecule and a hydroxyl content ranging from about 0.5 to about 25% by weight. They typically have a hydroxyl value of about 50 to as high as 500 or even 700.

[0115] In polyester-polyol reactants, the acid value should be less than 10, and generally as close to 0 as possible. These materials are simply referred to as "polyol" reactants. Available diols and / or polyols containing active hydrogen include a large family of addition compounds that are produced by adding (adding) ethylene oxide, propylene oxide, 1,2- and 2,3-epoxybutane, or other epoxides to active hydrogen compounds such as diols, glycols, and polyols (examples include ethylene glycol, propylene glycol, glycerol, methyl glucoside, sucrose, sorbitol, hexanetriol, trimethylolpropane, pentaerythritol), as well as various alkylamines and alkylene diamines and polyalkylene polyamines. Depending on the intended use of the polyurethane, varying amounts of these epoxides may be added to the indicated base diol, polyol, or amine molecule.

[0116] For example, the diols and / or polyols used in the manufacture of flexible foams can also be represented by glycerol, to which sufficient propylene oxide is added to obtain a final hydroxyl content of about 1.7%. Such a material would have a molecular weight of about 3,000 and a glycerol-to-propylene oxide molar ratio of about 1 glycerol to 50 propylene oxides.

[0117] The technique of controlling flexibility by selecting diol and / or polyol molecules and the amount of subsequently added epoxide alkane is well known in the art.

[0118] Besides diols, which can act as base polyol molecules to add alkyl epoxides and thereby produce "polyol" molecules for reaction with isocyanates, initial molecules containing primary and / or secondary amine groups with hydrogen atoms capable of reacting with alkyl epoxides can also be used. Similarly, the amount of alkyl epoxide added depends on the intended use of the final polyurethane product. In the flexible polyurethane products described herein, alkyl epoxides will be used to produce polyols with a low hydroxyl content, for example, from about 0.1% to about 5% or 10%.

[0119] Representative amines that can act as molecules containing active hydrogen to react with epoxides are those having 1 to 6 or more amino nitrogen atoms, examples of which are ethylamine, ethylenediamine (ethylenediamine), diethylenetriamine, triethylenetetramine, tetrapropylenepentamine, and other linear saturated aliphatic alkylene amines. An important requirement is that the epoxide can be added to at least two, and preferably more, i.e., 3 to 8 or 10 active hydrogen sites.

[0120] It is also known that the active hydrogen compounds used in the preparation of polyurethane systems are molecules with hydroxyl groups prepared by esterification-type reactions of polyfunctional acids or anhydrides and polyfunctional alcohols. These compounds are commonly referred to as polyester polyols. Typical acids used in the manufacture of these polyester polyols are maleic acid, phthalic acid, succinic acid, fumaric acid, tetrahydrophthalic acid, chlorobenzene, and tetrachlorophthalic acid. Typical glycols and / or polyols are ethylene glycol, propylene glycol, butanediol, diethylene glycol, and dipropylene glycol, as well as polyethylene glycol, polypropylene glycol, and glycerol, trimethylolpropane, hexanetriol, pentaerythritol, sorbitol, etc. Where applicable, the above-mentioned acids may be used in the form of anhydrides as needed.

[0121] In the manufacture of polyester polyols, any of various polyfunctional acids or anhydrides or mixtures thereof are reacted with any of diols, glycols, or polyols or mixtures thereof using an excess of hydroxyl groups in stoichiometric amounts, such that the final polyol product comprises primarily hydroxyl terminal groups (terminal groups). The degree of hydroxyl functionality and percentage of hydroxyl groups can be readily altered using one or more techniques known to those skilled in the art to provide a desired polyol.

[0122] In the field and technology of manufacturing flexible polyurethane, a technique known as prepolymer technology is also known. This technique involves carrying out a reaction as part of the manufacturing of flexible polyurethane to produce a prepolymer with increased molecular weight, depending on the stoichiometry used in manufacturing the prepolymer, resulting in either hydroxyl or isocyanate groups as end groups. The final flexible polyurethane product is then prepared using this prepolymer by reacting it with an isocyanate or a polyol, depending on whether the end groups of the prepolymer are hydroxyl or isocyanate groups as described above.

[0123] Broadly speaking, the polyurethanes described herein can be manufactured using any of the following: polyesters having free reactive hydrogen and, in particular, hydroxyl groups, isocyanate-modified polyester prepolymers, polyesteramides, isocyanate-modified polyesteramides, alkylene glycols, isocyanate-modified alkylene glycols, polyoxyalkylene glycols, isocyanate-modified polyoxyalkylene glycols, etc.

[0124] Examples of usable isocyanates include those having two or more isocyanate groups that have been used to date in the manufacture of flexible polyurethane foams. Examples of such isocyanate compounds include aromatic isocyanates, aliphatic isocyanates, and alicyclic isocyanates, and mixtures of two or more such isocyanates, as well as modified isocyanates obtained by modifying such isocyanates. Specific examples of such isocyanates are toluene diisocyanate, diphenylmethane diisocyanate, polymethylene polyphenylene polyisocyanate (crude MDI), xylene diisocyanate, isophorone diisocyanate, and hexamethylene diisocyanate; and modified products of such isocyanates, such as carbodiimide-modified products, biuret-modified products, dimers, and trimers. Prepolymers with terminal isocyanate groups obtained from such isocyanates and active hydrogen compounds can also be used.

[0125] In one embodiment, the isocyanate index of the flexible polyurethane foam may range from about 130 to about 80, more preferably from about 120 to about 90, and most preferably from about 115 to about 95.

[0126] As the blowing agent in the flexible polyurethane foam forming composition of the present invention, a known blowing agent used to date in such a composition is appropriately selected according to the desired properties of the foamed product.

[0127] In this invention, a crosslinking agent is also used, if necessary.

[0128] As a crosslinking agent, compounds having at least two functional groups possessing active hydrogen, such as hydroxyl, primary amino, or secondary amino groups, are preferred. However, in cases where a polyol compound is used as a crosslinking agent, the following is taken into consideration: That is, a polyol compound having a hydroxyl value of at least 50 mg KOH / g and more than four functional groups is considered as the crosslinking agent, and polyols that do not meet this requirement are considered as any one of the polyols in the above-mentioned polyol mixture (polyol (1), (2), or other polyols). Furthermore, two or more crosslinking agents may be used together. As specific examples, one may mention, for instance, polyols such as glucose, sorbitol, or sucrose; polyols having an epoxide added to the polyol; amine compounds such as monoethanolamine, diethanolamine, ethylenediamine, 3,5-diethyl-2,4 (or 2,6)-diaminotoluene (DETDA), 2-chloro-p-phenylenediamine (CPA), 3,5-bis(methylmercapto)-2,4 (or 2,6)-diaminotoluene, 1-trifluoromethyl-4-chloro-3,5-diaminobenzene, 2,4-toluenediamine, 2,6-toluenediamine, bis(3,5-dimethyl-4-aminophenyl)methane, 4,4'-diaminodiphenylmethane, m-xylylenediamine, 1,4-diaminohexane, 1,3-bis(aminomethyl)cyclohexane, or isophoronediamine; and compounds obtained by adding an epoxide to them.

[0129] When the above-mentioned crosslinking agents are used, even in cases where a large amount of foaming agent is used to manufacture flexible foams with low density, the foaming stability will be good, and it will be possible to manufacture such flexible foams. In particular, when high molecular weight glycols and / or polyols are used, it is possible to manufacture low-density flexible foams that have previously been considered difficult to foam. Furthermore, when crosslinking agents are used, durability is improved compared to when they are not used. In the case of using high molecular weight glycols and / or polyols in this invention, foaming stability can be easily improved, especially when using compounds with relatively high molecular weights, such as at least 4000.

[0130] Water is a typical example of such a blowing agent; other examples include dichloromethane, n-butane, isobutane, n-pentane, isopentane, dimethyl ether, acetone, carbon dioxide, etc. Depending on the desired density and other properties of the foamed polyurethane, these and other blowing agents may be used alone or in combination of two or more in a manner known in the art.

[0131] There are no particular restrictions on the amount of foaming agent used, but it is generally in the range of 0.1 to 20 parts by weight per 100 parts by weight of the diol and / or polyol components of the foam-forming composition. Preferably, the amount of foaming agent is such that it provides a foam density of 0.8-2.5 lbs / ft, and more preferably 0.9-2.0 lbs / ft.

[0132] The polyurethane foam forming compositions described herein preferably include any and combinations of catalysts known or used to date in the manufacture of polyurethane foams. Examples of usable catalysts include sodium hydroxide, sodium acetate, tertiary amines or materials that produce tertiary amines, such as trimethylamine, triethylenediamine, N-methylmorpholine, N,N-dimethylcyclohexylamine, and N,N-dimethylaminoethanol. Also suitable are metal compounds such as hydrogentin alkyl carboxylate, dibutyltin diacetate, dibutyltin dioctanoate, dibutyltin dilaurate, and stannous octanoate; and other compounds intended to promote the trimerization of isocyanates, such as 2,4,6-tris(N,N-dimethylamino-methyl)phenol, 1,3,5-tris(N,N-dimethyl-3-aminopropyl)-S-hexahydrotriazine, potassium octanoate, potassium acetate, and catalysts such as DABCO. and POLYCAT

[0133] Many other types of catalysts can be used instead of those listed above, as needed. The amount of catalyst used can advantageously be in the range of 0.05-5% by weight or greater, based on the total weight of the diols and / or polyols in the foam-forming mixture.

[0134] The isocyanate (NCO) index used in the manufacture of the flexible foam according to the invention is 95-125, and preferably 100-120. It is generally understood that the NCO index of polyurethane foam is about 80-130.

[0135] The density range of flexible polyurethane foam in this article can be 14-80, preferably 16-55, and most preferably 20-40 kg / m³. 3 .

[0136] Surfactants, including organic surfactants and silicone-based surfactants, can be added to act as cell stabilizers. Some representative materials are sold under the names SF-1109, L-520, L-521, and DC-193 (which are typically polysiloxane-polyoxyalkylene block copolymers). Organic surfactants comprising polyoxyethylene-polyoxybutylene block copolymers are also included. It is particularly desirable to use a small amount of surfactant to stabilize the foaming reaction mixture until it cures. Other surfactants that may be used herein are polyethylene glycol ethers of long-chain alcohols, long-chain allyl sulfates, alkyl sulfonates, tertiary amines or alkanolamine salts of alkyl aryl sulfonic acids, and combinations thereof. Such surfactants are used in amounts sufficient to stabilize the foaming reaction against collapse and the formation of large, uneven cells. Typically, a total surfactant amount of about 0.2 to about 3 wt% of the formulation as a whole is sufficient for this purpose. However, including certain surfactants, such as DABCO DC-5598, available from Air Products and Chemicals, Inc., in higher amounts may be desirable in some embodiments. Therefore, in the formulations of the present invention, surfactants may be included in any amount ranging from 0-6 wt.% based on the diol and / or polyol components.

[0137] Finally, the polyurethane foam forming formulations described herein may include other additives such as fillers and pigments. These, in non-limiting embodiments, may include barium sulfate, calcium carbonate, graphite, carbon black, titanium dioxide, iron oxide, microspheres, alumina trihydrate, wollastonite, prepared glass fibers (dropped or continuous), polyester fibers, other polymer fibers, combinations thereof, etc. Those skilled in the art will recognize that typical and suitable means and methods for manufacturing flexible polyurethane foams using the formulations of the present invention require no further guidance, and that such flexible polyurethane foams, while still falling within the scope of the appended claims, exhibit or benefit from desired properties and / or processing modifications.

[0138] The flexible polyurethane foam described herein can be used in the construction and formation of a wide variety of products, such as furniture, bedding, and car seat cushions, and more particularly furniture, automotive, marine, bus, train, RV, office furniture, aviation, tractor, bicycle, engine rack, compressor, bedding, insulation, sports equipment, footwear, carpet, packaging, textiles, cushioning, HVAC, tents, life rafts, luggage, and handbags.

[0139] Flexible polyurethane foam can be used in furniture such as upholstered furniture (e.g., padding, backrests, and armrests), in the automotive industry such as for cars and trucks, for public transportation seats (e.g., buses and airplanes), and for seat and back padding, headrests, and headrests in tractor units, bicycles, and e-bikes, including but not limited to seat bottom and back pads, armrests, support rings for run-flat tires, and other automotive interior components; bedding such as mattresses, seat sound insulation materials, automotive interior components such as elbow rests, steering wheels and gear shift knobs, shoe soles, and sports equipment.

[0140] The following examples illustrate specific implementations of the preparation of certain compounds of the present invention and the effectiveness of these compounds as reactive flame retardants in flexible polyurethane foams.

[0141] Example

[0142] Preparation Example 1

[0143]

[0144] Diethylphosphonic acid (779 g, 6.38 mol) was added to a 2-liter jacketed Hastelloy reactor equipped with a mechanical stirrer, oil heater, and positive displacement laboratory pump, and the reactor was sealed. The reactor was heated to an internal temperature of 45°C. Propylene oxide (743 g, 12.77 mol) was added to the reactor via the pump over two hours while the temperature was maintained below 65°C. Subsequently, the internal temperature of the reactor was raised to 90°C and maintained at that temperature for three hours. Excess propylene oxide was evaporated, and the residue was distilled under vacuum (300-500 mTorr) at a jacketed temperature of 125°C using a scraped thin-film evaporator. The target fraction was collected as a clear, colorless liquid. The yield was 90% relative to the initial diethylphosphonic acid. The product was a mixture of two isomers of the hydroxyl-functionalized ester of diethylphosphonic acid. 31 P NMR (acetic acid-d4, ppm): 66.8–67.7; and has an acid value of 0.4 mg KOH / g and a phosphorus content of 15.9%.

[0145] Preparation Example 2

[0146]

[0147] Diethylphosphonic acid (469 g, 3.84 mol) was added to a 1-liter flask equipped with a heating mantle, mechanical stirrer, reflux condenser, suction tube, J-CHEM controller and thermocouple, and alkaline gas scrubber. The flask was heated to 80°C, and ethylene oxide from a pressurized gas cylinder was added to the reactor via the suction tube over a period of five hours. The final molar ratio of ethylene oxide to diethylphosphonic acid was 1.33. The reaction mixture was maintained at 80°C for another three hours. Nitrogen was further passed through the suction tube to remove excess ethylene oxide. Intermittent distillation of the residue was performed at 150°C and 200 mTorr to produce a clear liquid (400 g). The product was a 2-hydroxyethyl ester of diethylphosphonic acid. 31 P NMR (CDCl3, ppm): 79; and has an acidity of 0.4 mg KOH / g.

[0148] Application Example 3

[0149] MVSS 302 test This test is a horizontal combustion test used as a guideline for automobile manufacturers. The sample dimensions are 14″ × 4″ × 1 / 2″. The distance from the ignition point is 1... 1 / 2″ Wired. Combustion is initiated by ignition for fifteen seconds. Then the ignition source is turned off and the sample is rated. A "DNI" rating indicates that the sample does not support combustion ("unignitable"). A "SE" rating indicates that the sample was ignited but did not burn to the following time zone: which is from 1 1 Starting from the / 2″ mark, the sequence continues up to 3. 1 The position of the / 2″ line. The "SENBR" rating indicates that the sample has been burned for 1... 1 / 2″ line but in 3 1 The flame extinguishes before the / 2″ mark. The "SE / B" rating indicates that the sample burned for 3 seconds. 1 Mark the sample with a 2″ mark but extinguish it before the endpoint. Then calculate the rate in inches per minute. This flammability rating refers to the sample burning for 3 seconds. 1 / 2″ marking. A flammability rating higher than 4.0 in / min or an SE / B rating indicates failure according to this test. Minimum SENBR performance is required for this study.

[0150] The compression set was 90% as determined by ASTM D3574.

[0151] Material:

[0152] Desmophen 60WB01 is a polyester polyol available from Covestro.

[0153] BPPE and BPPE-HP are butylated triaryl phosphates available from ICL-IP America.

[0154] BDP is bisphenol A bis(diphenyl phosphate) available from ICL-IP America.

[0155] TBEP is a tris(2-butoxyethyl) phosphate ester available from ICL-IP America.

[0156] ADP is isodecyl diphenyl phosphate, which is available from ICL-IP America.

[0157] Niax C-131NPF is an amine catalyst available from Momentive.

[0158] Niax DMP is an amine catalyst available from Momentive.

[0159] Niax L-537XF is an organosilicon stabilizer available from Momentive.

[0160] TD 80 is an isocyanate material available from BASF.

[0161] TD 65 is an isocyanate material available from Covestro.

[0162] The A / B ratio is the ratio of the remaining components of the TDI-matched formulation.

[0163] When RPE (the reactive phosphonate ester of the present invention) (which is the reactive phosphonate ester prepared in Preparation Example 1 above) was used in Application Examples 3 and 4 below, the RPE demonstrated high efficiency in the above MVSS 302 test, passing the SE grade with only 4 parts in a 1.8 pcf density polyurethane foam. Butylated triaryl phosphate products such as BPPE and BPPE-HP (in a low TPP content form) required 10 parts to pass the SE grade. Bisphosphonate products such as BDP required 12 parts to pass the SENBR grade. Unexpectedly, it was found that 20 / 80 blends of RPE and phosphate esters, such as BPPE-type products, could also pass the MVSS 302 SE grade with only 4 parts, and similar blends containing bisphosphonates such as BDP could pass the SENBR grade at the same loading. These blends have similar efficacy to 4 parts of RPE and contain only 0.8 parts of the highly efficient reactive FR product. The majority of each blend consists of the inefficient phosphate ester products BPPE and BDP. Even a 20 / 80 blend of 6 parts RPE and a phosphate ester (such as TBEP) passed the SE grade. A 20 / 80 blend of 8 parts RPE and a phosphate ester (such as isodecyl diphenyl phosphate) passed the SENBR grade.

[0164] Because it is impractical to expect such high FR efficacy from such a low level (0.8 parts) of RPE in the presence of inefficient phosphate ester products (3.2 parts), it is evident that a synergistic relationship exists between reactive phosphonate ester products RPE and various phosphate esters. The phosphonate / phosphate ester blends shown below contain 30-35% less phosphorus than the RPE product and still retain the same FR efficacy. This synergy also extends to a wide variety of phosphate ester products, in which RPE is blended with trialkyl phosphate products TBEP and ADP products, as shown in the table in Application Example 3 below.

[0165] In addition to maintaining high levels of flame retardant properties through these RPE / phosphate blends, it is worth noting that the resulting foam exhibits significantly improved physical properties (e.g., compression set) compared to those observed when using RPE products alone. It is known that reactive flame retardant products disrupt the normal foaming process, resulting in poor foam physical properties. In most cases, this is readily observable through the loss of the foam's resilience after compression at elevated temperatures. Compression testing according to ASTM D3574 is a standard foam requirement and ensures that compressed foam does indeed spring back. By using a small amount of RPE product in the phosphonate / phosphate blend, the negative effects of using reactive FR products are avoided, while retaining the high FR efficacy required in end-use products. The RPE / phosphate blend retains both excellent FR performance and good physical properties.

[0166]

[0167]

[0168] Summary of synergistic effects

[0169] For the table below, see Figure 1

[0170]

[0171] For the table below, see Figure 2

[0172]

[0173] Figure 1 and Figure 2 The dashed lines in both represent the expected flame retardant loading levels based on the simple linear relationship between the two flame retardants described herein, in the absence of synergistic effects. Figure 1 and 2All points below the dashed line (solid line) in each blend demonstrate that significantly less flame retardant is needed than would be expected based on a simple linear relationship between the acceptable levels of the two flame retardant products. This fact that the blend requires less flame retardant than would be expected demonstrates the synergistic relationship between the two flame retardants in the blend.

[0174] Although the invention has been described with reference to certain embodiments, those skilled in the art will understand that various changes can be made and its elements can be substituted with equivalents without departing from the scope of the invention. Furthermore, many changes can be made without departing from its essential scope to make particular scenarios or materials suitable for the teachings of the invention. Therefore, it is intended that the invention not be limited to the specific embodiments disclosed as the best mode contemplated for carrying out the invention, but rather that the invention cover all embodiments falling within the scope of the appended claims.

Claims

1. Flame-retardant blends, including: (1) Monohydroxy functional dialkylphosphinate compounds of formula (IA): (I-A) in: R 1 and R 2 Selected from linear or branched alkyl groups containing 1-4 carbon atoms; and, X is R 3 or ; R 3 Linear or branched alkylene groups with monohydroxyl-terminated caps containing 2 to 8 carbon atoms; and, When X is At that time, R 4 and R 5 Each is independently selected from H, linear or branched alkyl groups containing 1-8 carbon atoms, linear or branched alkenyl groups containing 2-8 carbon atoms, halogen-substituted alkyl groups containing 1-8 carbon atoms, alkoxy groups containing 1-8 carbon atoms, aryl groups containing 6-12 carbon atoms, and alkylaryl groups containing 7-16 carbon atoms, or R. 4 and R 5 They bond to each other to form cycloalkyl groups containing 5 to 8 carbon atoms; and, (2) Phosphate compounds.

2. The flame-retardant blend as described in claim 1, wherein R 1 and R 2 Each is an ethyl group.

3. The flame-retardant blend of claim 1, wherein the monohydroxy-functional dialkylphosphinate compound has the formula (IA-2): (I-A-2)。 4. The flame-retardant blend as described in claim 3, wherein R 1 and R 2 Each is an ethyl group.

5. The flame-retardant blend of claim 1, wherein the phosphate compound is selected from (tert-butylphenyl) phosphate (phenyl) mixed ester, resorcinol bis(diphenyl phosphate), bisphenol A bis(diphenyl phosphate), tris(2-butoxyethyl) phosphate, and combinations thereof.

6. The flame-retardant blend of claim 1, further comprising a halogenated phosphate compound selected from: tris(1,3-dichloro-2-propyl) phosphate (TDCP); oxydi-2,1-ethanediyl-bis(2-chloro-1-methylethyl) phosphate; 2,2-bis(chloromethyl)-1,3-propanediylbis[bis(2-chloroethyl) phosphate]; 2,2-bis(chloromethyl)-1,3-propanediyltetra(2-chloro-1-methylethyl) diphosphate; and combinations thereof.

7. A flame-retardant flexible polyurethane foam comprising a polyol, an isocyanate, and a flame-retardant effective amount of the reaction product of the flame-retardant blend as described in claim 1.

8. An article comprising the flame-retardant flexible polyurethane foam as described in claim 7.

9. An application article comprising the article of claim 8, wherein the application article is selected from furniture, automotive, marine, train seating, aviation, tractor, bicycle, engine rack, compressor, bedding, isolation, sports equipment, footwear, carpet, packaging, textile, cushioning, HVAC, tent, life raft, luggage, and handbag.

10. The application article of claim 9, wherein the automotive accessory is selected from bus seat accessories and RV seat accessories.

11. The application article of claim 9, wherein the furniture is selected from office furniture seating.

12. The application article of claim 9, wherein the furniture is upholstered furniture.

13. The application article of claim 9, wherein the automotive articles are selected from car seat cushions, headrests and headrests, backrests for cars and trucks, bus seats, seat bottom and backrest pads, armrests, and support rings for run-flat tires.

14. The application article of claim 9, wherein the bedding is selected from mattresses.

15. An application article comprising the article of claim 8, wherein the application article is selected from sound-insulating materials.

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