Polyurethane foam with improved combustion properties

Abstract

The present disclosure provides an isocyanate reactive composition that can react with an isocyanate compound in a reaction mixture to form a polyurethane-based foam. The isocyanate reactive composition comprises an isocyanate reactive compound and a combustion regulator composition. The isocyanate reactive compound has an isocyanate reactive portion and an aromatic portion. The combustion regulator composition comprises phosphorus from a halogen-free flame retardant compound and a transition metal from a transition metal compound. The molar ratio of the transition metal to phosphorus of the combustion regulator composition (moles of transition metal: moles of phosphorus) can be 0.05:1 to 5:1.

Description

Technical Field

[0001] The present disclosure relates generally to polyurethane-based foams, and more particularly to polyurethane-based foams having improved combustion properties. Background Art

[0002] Since the 1960s, polyurethane rigid (PUR) foam has been used in construction as a high-performance insulating material. Continuous technological development in Europe and the United States has given rise to a next-generation product called polyisocyanurate rigid (PIR) foam. Both PUR and PIR are polyurethane-based foams made from two reactants, isocyanates (e.g., diphenyl methyl diisocyanate, MDI) and polyols. While for PUR, isocyanates and polyols are implemented in a balanced ratio equivalent to equivalent weights, excess isocyanates are used in the production process of PIR. The isocyanate part reacts with itself, and the resulting PIR is a highly cross-linked synthetic material with a cyclic isocyanurate structure. The high degree of bonding and the ring structure ensure the high thermal stability of rigid PIR foams. PIR also has excellent dimensional stability.

[0003] PIR foams are also characterized by very good fire protection properties due to the inherent charring properties, which in turn is related to the excellent thermal stability of the isocyanurate chemical structure. To further enhance the char formation, phosphorus-based flame retardants are usually added. When building products such as insulated metal panels or insulating boards are exposed to fire, the insulating PIR core quickly forms an adherent char that helps protect the underlying materials. This means that only a limited portion of the available combustible insulation materials are exposed to the fire, and these materials actually contribute to the release of heat and smoke.

[0004] The combustion performance of combustible thermosets is a complex issue. For example, halogenated flame retardants are very effective in reducing heat release, but may worsen opacity. Dow patent publication US 2014 / 0206786A1 describes the use of triethyl phosphate (TEP) as a smoke suppression additive compared to traditional halogenated flame retardants such as tris(2-chloroisopropyl) phosphate (TCPP). In addition, it is well known that the composition of combustion effluents (in addition to the material itself) depends largely on the fire conditions, particularly temperature, geometry and ventilation, including the availability of oxygen. Even though, as described above, the inherent charring properties of polyisocyanurates limit and / or delay the amount of polymer combustion (thereby limiting and / or delaying the release of heat and smoke), there is still a need to further improve the combustion (combustion / burning) performance and thereby reduce opacity and smoke toxicity as much as possible. Summary of the invention

[0005] The present disclosure provides a polyurethane-based foam having improved combustion performance with respect to the emission of hydrogen cyanide (HCN) and carbon monoxide (CO) during a pyrolysis event (e.g., a fire). The polyurethane-based foam is formed with a reaction mixture comprising an isocyanate compound and an isocyanate-reactive composition. The isocyanate-reactive composition for the polyurethane-based foam, among other things, comprises phosphorus from a halogen-free flame retardant compound and a transition metal from a transition metal compound, which together contribute to significantly reducing the generation of HCN and CO during pyrolysis of the polyurethane-based foam.

[0006] For embodiments of the present disclosure, an isocyanate-reactive composition for forming a polyurethane-based foam comprises an isocyanate-reactive compound and a combustion modifier composition. The isocyanate-reactive compound has an isocyanate-reactive portion and an aromatic portion, wherein the aromatic portion is 5 weight percent (wt.%) to 80 wt.% of the isocyanate-reactive compound based on the total weight of the isocyanate-reactive compound. The combustion modifier composition comprises 0.1 wt.% to 7.0 wt.% phosphorus from a halogen-free flame retardant compound and 0.05 wt.% to 14.0 wt.% transition metal from a transition metal compound, wherein the wt.% of the transition metal and the wt.% of the phosphorus are based on the total weight of the isocyanate-reactive compound, the halogen-free flame retardant compound, and the transition metal compound, respectively. For these given wt.% values, the molar ratio of the transition metal to phosphorus of the combustion modifier composition (moles of transition metal: moles of phosphorus) can be 0.05:1 to 5:1.

[0007] For the embodiments provided herein, the halogen-free flame retardant compound may be selected from the group consisting of: phosphates, phosphonates, phosphinates, and combinations thereof. For the embodiments provided herein, the transition metal compound may be selected from the group consisting of oxides, carboxylates, salts, coordination compounds, and combinations thereof, wherein the transition metal may be selected from the group consisting of copper, iron, manganese, cobalt, nickel, zinc, and combinations thereof. Preferably, the transition metal compound is selected from the group consisting of: copper (I) oxide, copper (II) oxide, ethylenediaminetetraacetic acid (EDTA) copper disodium salt, and combinations thereof. For each embodiment, the transition metal compound preferably has a median particle size (D50) of 10 nm to 10 μm. For the embodiments provided herein, the isocyanate-reactive portion of the isocyanate-reactive compound may be a hydroxyl portion, wherein the isocyanate-reactive compound is selected from the group consisting of: polyether polyols, polyester polyols, polycarbonate polyols, polyester carbonate polyols, polyether carbonate polyols, and combinations thereof. For each embodiment, the isocyanate-reactive composition provided herein may also include a catalyst, a surfactant, a blowing agent, or a combination thereof.

[0008] The reaction mixture for forming a polyurethane-based foam comprises an isocyanate compound having an isocyanate moiety and an isocyanate-reactive compound having an isocyanate-reactive moiety and an aromatic moiety, wherein the aromatic moiety accounts for 5 wt.% to 80 wt.% of the isocyanate-reactive compound based on the total weight of the isocyanate-reactive compound as provided herein. For the embodiments herein, the molar ratio of the isocyanate moiety to the isocyanate-reactive moiety of the reaction mixture can be 1.2:1 to 7:1. For example, the isocyanate-reactive moiety of the isocyanate-reactive composition is a hydroxyl moiety, wherein the molar ratio of the isocyanate moiety to the hydroxyl moiety of the reaction mixture is 1.2:1 to 7:1. The reaction mixture also comprises 0.1 wt.% to 7.0 wt.% of phosphorus from a halogen-free flame retardant compound and 0.05 wt.% to 14.0 wt.% of a transition metal from a transition metal compound, wherein the wt.% values ​​of phosphorus and transition metal are based on the total weight of the isocyanate-reactive compound, the halogen-free flame retardant compound and the transition metal compound. The reaction mixture may also optionally include a catalyst, a surfactant, and a blowing agent for forming a polyurethane-based foam.As discussed herein, a polyurethane-based foam is formed with the reaction mixture.

[0009] The present disclosure also provides a method for preparing a reaction mixture for producing a polyurethane-based foam. The method may include providing an isocyanate compound having an isocyanate portion; providing an isocyanate reactive compound having an isocyanate reactive portion and an aromatic portion, wherein the aromatic portion accounts for 5 wt.% to 80 wt.% of the isocyanate reactive compound based on the total weight of the isocyanate reactive compound; providing 0.1 wt.% to 7.0 wt.% of phosphorus from a halogen-free flame retardant compound and 0.05 wt.% to 14.0 wt.% of a transition metal from a transition metal compound, wherein the wt.% values ​​of phosphorus and transition metal are based on the total weight of the isocyanate reactive compound, the halogen-free flame retardant compound, and the transition metal compound; optionally providing a catalyst, a surfactant, and a blowing agent; and mixing the isocyanate compound, the isocyanate reactive compound, the halogen-free flame retardant compound, the transition metal compound, the optional catalyst, the surfactant, and the blowing agent to form a reaction mixture. For each embodiment, the molar ratio of the isocyanate portion to the isocyanate reactive portion of the reaction mixture may be 1.2:1 to 7:1. Mixing to form a reaction mixture may also include providing a transition metal to phosphorus molar ratio (moles transition metal:moles phosphorus) in the reaction mixture of 0.05:1 to 5:1. Another embodiment of the method further includes mixing the transition metal compound with a liquid carrier to provide the transition metal from the transition metal compound. DETAILED DESCRIPTION

[0010] The present disclosure provides a kind of polyurethane-based foam, and it has improved combustion performance with respect to the emission of hydrogen cyanide (HCN) and carbon monoxide (CO) during pyrolysis event (for example, fire).The foam based on polyurethane is formed with the reaction mixture comprising isocyanate compound and isocyanate reactive composition.For the embodiment of the present disclosure, the isocyanate reactive composition for forming the foam based on polyurethane comprises the isocyanate reactive compound with isocyanate reactive part and aromatic part as provided herein.The isocyanate reactive composition also comprises phosphorus from halogen-free flame retardant compound and transition metal from transition metal compound, and they together contribute to significantly reduce the generation of HCN and CO during the pyrolysis of the foam based on polyurethane.

[0011] For various embodiments, the isocyanate reactive part of the isocyanate reactive compound is a hydroxyl part, wherein the isocyanate reactive compound can be selected from the group consisting of: polyether polyols, polyester polyols, polycarbonate polyols, polyester carbonates, polyether carbonate polyols and combinations thereof. For various embodiments, the isocyanate reactive compound may contain two or more hydroxyl parts, wherein the active hydrogen atom reacts with the carbon atom of the isocyanate group (-N=C=O) of the isocyanate compound. The number average molecular weight of the isocyanate reactive compound can be 100 g / mol to 2,000 g / mol. Other number average molecular weight values ​​are also possible. For example, the number average molecular weight of the isocyanate reactive compound can be a low value of 100, 200, 300, 350 or 400 g / mol to a high value of 500, 750, 1,000, 1,500 or 2,000 g / mol. The number average molecular weight values ​​reported herein are determined by end group analysis, gel permeation chromatography and other methods as known in the art.

[0012] The isocyanate-reactive compound also includes an aromatic portion. For each embodiment, the aromatic portion is 5 weight percent (wt.%) to 80wt.% of the isocyanate-reactive compound based on the total weight of the isocyanate-reactive compound. Preferably, based on the total weight of the isocyanate-reactive compound, the aromatic portion constitutes 8wt.% to 50wt.% of the isocyanate-reactive compound. More preferably, based on the total weight of the isocyanate-reactive compound, the aromatic portion constitutes 10wt.% to 40wt.% of the isocyanate-reactive compound. As used herein, "aromatic portion" is at least one cyclic conjugated molecular portion in the form of a planar unsaturated carbon atom ring covalently attached to the isocyanate-reactive compound. The planar unsaturated ring of carbon atoms may have at least six (6) carbon atoms. For illustration, the isocyanate-reactive compound bis(2-hydroxyethyl)terephthalate has C 12 H 14O6 molecular formula and a formula weight of 254.2 g / mol, and has an aromatic content corresponding to the C6H4 molecular formula and a corresponding formula weight of 76.1 g / mol, wherein the aromatic portion of bis(2-hydroxyethyl)terephthalate is 29.9 weight percent (wt.%).

[0013] For example, the polyether polyols may include those having at least 2, such as 2 or 3 hydroxyl groups per molecule, and may be prepared as follows: for example, by polymerizing epoxides / cyclic ethers such as ethylene oxide, propylene oxide, butylene oxide, styrene oxide or epichlorohydrin by themselves in the presence of BF3, or by chemically adding these epoxides, optionally in the form of a mixture (such as a mixture of ethylene oxide and propylene oxide) or in sequence, to a starting component having a reactive hydrogen atom such as water, ammonia, ethanol or amine. Examples of suitable starting components include ethylene glycol, propylene glycol-(1,3) or -(1,2), glycerol, trimethylolpropane, 4,4'-dihydroxy-diphenylpropane, Novolac, aniline, ethanolamine, o-toluenediamine or ethylenediamine. Sucrose-based polyether polyols may also be used. In many cases it is preferred to use polyethers containing a dominant amount of primary OH groups (up to 100% of the OH groups present in the polyether).

[0014] For some embodiments, polyester polyols may include those having at least 1.8 to 3 hydroxyls (average) per molecule. Examples of polyester polyols may include those formed as the reaction product of polyhydroxy (such as dihydric alcohol and / or trihydric alcohol) and polyvalent (such as dibasic and / or tribasic) carboxylic acids. Instead of free polycarboxylic acids, corresponding polycarboxylic acid esters or mixtures thereof of corresponding polycarboxylic acid anhydrides or lower alcohols and mixtures thereof with free polycarboxylic acids may be used. Polycarboxylic acids may be aliphatic, alicyclic, aromatic and / or heterocyclic, and may be substituted by, for example, halogen atoms, and / or may be unsaturated. Suitable exemplary polycarboxylic acids, anhydrides and polycarboxylates of lower alcohols include, but are not limited to, succinic acid, adipic acid, suberic acid, azelaic acid, sebacic acid, phthalic acid, isophthalic acid, terephthalic acid, trimellitic acid, phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, tetrachlorophthalic anhydride, endomethylenetetrahydrophthalic anhydride, glutaric anhydride, maleic acid, maleic anhydride, fumaric acid, dimerized and trimerized fatty acids, optionally mixed with monomeric fatty acids, dimethyl terephthalate and bis-ethylene glycol terephthalate. Examples of other suitable polyester polyols include modified aromatic polyester polyols such as those supplied under the trade name STEPANPOL PS-2352 (acid value, max 0.6-1.0 mg KOH / g, hydroxyl value 230-250 mg KOH / g, functionality 2.0, Stepan Company).

[0015] Exemplary suitable polyols include, but are not limited to, ethylene glycol, propylene glycol-(1,2) and -(1,3), butanediol-(1,4) and -(2,3), hexanediol-(1,6), octanediol-(1,8), neopentyl glycol, cyclohexanedimethanol (1,4-bis-hydroxy-methylcyclohexane and other isomers), 2-methyl-1,3-propanediol, glycerol, trimethylolpropane, hexanetriol-(1,2,6), butanetriol-(1,2,4), trimethylolethane, pentaerythritol, quinitol, mannitol and sorbitol, methyl glycosides, diethylene glycol, triethylene glycol, tetraethylene glycol, polyethylene glycol, dipropylene glycol, polypropylene glycol, dibutylene glycol and polybutylene glycol. The polyesters may also contain a certain proportion of carboxyl end groups. Polyesters of lactones such as ε-caprolactone or hydroxycarboxylic acids such as co-hydroxycaproic acid may also be used.

[0016] For some embodiments, polyester polyol is aromatic polyester polyol.The example of aromatic polyester polyol includes those formed by the reaction product of aromatic polyacid and aliphatic polyol.Other examples include the reaction product formed by the reaction of at least one polyacid including terephthalic acid, isophthalic acid, phthalic acid, phthalic anhydride, trimellitic acid or trimellitic anhydride and at least one aliphatic polyol including ethylene glycol, propylene glycol, diethylene glycol, polyethylene glycol, polypropylene glycol or glycerine.In other examples, aromatic polyester polyol is the reaction product formed by the polyacid of terephthalic acid and by the aliphatic polyol including diethylene glycol, polyethylene glycol and / or glycerine. For various embodiments, the aromatic polyester polyol has an aromatic content of a low of 8, 10, 12, or 14 weight percent (wt.%) and a high of 18, 20, 30, or 40 wt.%, based on the total weight of the polyester polyol, wherein any combination of the provided low and high values ​​are possible (e.g., the aromatic polyester polyol has an aromatic content of 8 wt.% to 40 wt.%). For some embodiments, the aromatic polyester polyol has an average hydroxyl functionality as low as 1.8, 1.9, or 2.0 and as high as 2.4, 2.7, or 3.0, wherein any combination of the provided low and high values ​​are possible (e.g., the average hydroxyl functionality is 1.8 to 3.0). For some embodiments, the number average molecular weight of the aromatic polyester polyol is as low as 300, 350, 400, or 425 and as high as 525, 550, 600, or 800, wherein any combination of the provided low and high values ​​are possible (e.g., the aromatic polyester polyol has a number average molecular weight of 300 to 800).

[0017] Such polyol components may also include polycarbonate polyols such as the reaction products of diols (e.g., propylene glycol-(1,3), butanediol-(1,4) and / or hexanediol-(1,6), diethylene glycol, triethylene glycol or tetraethylene glycol) with diaryl carbonates (e.g., diphenyl carbonate), dialiphatic carbonates (e.g., dimethyl carbonate) or phosgene, or from the reaction of epoxides and carbon dioxide.

[0018] Other examples of suitable isocyanate-reactive compounds include those polymers or copolymers having a hydroxyl equivalent of at least 75 formed with propylene oxide. Propylene oxide may be 1,3-propylene oxide, but more typically 1,2-propylene oxide. If it is a copolymer, the comonomer is another copolymerizable alkylene oxide, such as ethylene oxide, 2,3-butylene oxide, tetrahydrofuran, 1,2-hexylene oxide, etc. The copolymer may contain 25% by weight or more, 50% by weight or more, and preferably 75% by weight or more of polymerized propylene oxide. Isocyanate-reactive compounds may also include those polymers formed by 100% propylene oxide based on the total weight of polymerized alkylene oxide. The copolymer preferably contains no more than 75% by weight, especially no more than 50% by weight of polymerized ethylene oxide. The nominal functionality of the polymer or copolymer of propylene oxide should be at least 2.0. The nominal functionality is preferably 2.5 to 8, more preferably 2.5 to 7 or 2.5 to 6. The polymer or copolymer of propylene oxide has a hydroxyl equivalent of at least 100, preferably at least 150, more preferably 150 to 1.000, and in some embodiments 150 to 750. The isocyanate reactive compound may also be formed from a blend, wherein the polyol blend may include a blend of diols and triols. The average molecular weight (Mw) of the diol may be 300 to 8,000 g / mole, and the average molecular weight (Mw) of the triol may be 500 to 6.500 g / mole.

[0019] In various embodiments, a suitable isocyanate-reactive compound without an aromatic portion can be blended with a suitable isocyanate-reactive compound with an aromatic portion. In the isocyanate-reactive compound that is a mixture of a non-aromatic isocyanate-reactive compound and an aromatic isocyanate-reactive compound, the aromatic content of the isocyanate-reactive compound containing the aromatic portion is 5 weight percent (wt.%) to 80 wt.%. Preferably, the aromatic portion constitutes 8 wt.% to 50 wt.% of the isocyanate-reactive compound containing the aromatic portion. More preferably, the aromatic portion constitutes 10 wt.% to 40 wt.% of the isocyanate-reactive compound containing the aromatic portion.

[0020] In various embodiments, the hydroxyl value of the isocyanate reactive compound can be 10 mg KOH / g to 700 mg KOH / g. In other embodiments, the hydroxyl value of the isocyanate reactive compound can be 100 mg KOH / g to 500 mg KOH / g, or 150 mg KOH / g to 400 mg KOH / g, or 190 mg KOH / g to 350 mg KOH / g. As used herein, the hydroxyl value is the milligrams of potassium hydroxide, which is equivalent to the hydroxyl content in one gram of polyol or other hydroxy compound. The number average isocyanate reactive group functionality of the polyol can also be 1.8 to 3, such as 2 to 2.7 or 2 to 2.5.

[0021] For various embodiments, the polyether polyols and / or polyester polyols may also be uncapped or capped with ethylene oxide (EO) and / or propylene oxide (PO) as known in the art to provide a hydrophilic or hydrophobic structure.

[0022] In the present disclosure, other isocyanate reactive compositions other than polyol components can be used to form the isocyanate reactive compositions of the present disclosure. This can realize the two-component system of isocyanate reactive compositions, wherein instead of polyols as provided herein or in addition to polyols as provided herein, amines can also be used as curing agents. Such isocyanate reactive compositions can include aromatic diamines, such as those containing at least one alkyl substituent located at the ortho position of the first amino group and two alkyl substituents located at the ortho position of the second amino group or a mixture thereof. In certain embodiments, at least two of the alkyl substituents contain at least two carbon atoms. In certain embodiments, the reactivity of diamines to isocyanates has not yet been reduced by electron attraction such as halogen, ester, ether or disulfide and other substituents, as is the case with methylene-bis-chloroaniline (MOCA). In certain embodiments, such diamines do not contain other functional groups that react with isocyanates. In certain embodiments, the above-mentioned alkyl substituents may have up to twenty carbon atoms and may be straight or branched long chains.

[0023] The isocyanate reactive composition for forming a polyurethane-based foam also includes a combustion modifier composition. For each embodiment, the combustion modifier composition includes 0.1wt.% to 7.0wt.% phosphorus from a halogen-free flame retardant compound and 0.05wt.% to 14.0wt.% transition metal from a transition metal compound, wherein the wt.% of phosphorus and transition metal is based on the total weight of the isocyanate reactive compound, the halogen-free flame retardant compound and the transition metal compound. Preferably, the combustion modifier composition includes 0.3wt.% to 5.0wt.% phosphorus from a halogen-free flame retardant compound, wherein the wt.% of phosphorus from the halogen-free flame retardant compound is based on the total weight of the isocyanate reactive compound, the halogen-free flame retardant compound and the transition metal compound; and 0.1wt.% to 5.0wt.% transition metal from a transition metal compound, which is based on the total weight of the isocyanate reactive compound, the halogen-free flame retardant compound and the transition metal compound. More preferably, the combustion modifier composition comprises 1.0 wt.% to 3.0 wt.% phosphorus from the halogen-free flame retardant compound, the wt.% of phosphorus from the halogen-free flame retardant compound being based on the total weight of the isocyanate-reactive compound, the halogen-free flame retardant compound and the transition metal compound; and 0.3 wt.% to 2.0 wt.% transition metal from the transition metal compound, which is based on the total weight of the isocyanate-reactive compound, the halogen-free flame retardant compound and the transition metal compound. For the given weight percentage values, the molar ratio of transition metal to phosphorus (moles of transition metal: moles of phosphorus) of the combustion modifier composition is 0.05:1 to 5:1. Preferably, the molar ratio of transition metal to phosphorus (moles of transition metal: moles of phosphorus) is 0.10:1 to 3:1. More preferably, the molar ratio of transition metal to phosphorus (moles of transition metal: moles of phosphorus) is 0.15:1 to 1:1.

[0024] For the embodiments provided herein, the halogen-free flame retardant compound is selected from the group consisting of: phosphate, polyphosphate, phosphonate, phosphinate, bisphosphinate and combinations thereof. Examples of phosphate include trialkyl phosphate, triaryl phosphate, phosphate and resorcinol bis (diphenyl phosphate). As used herein, trialkyl phosphate has at least one alkyl group with 2 to 12 carbon atoms. The other two alkyl groups of trialkyl phosphate can be independently the same or different from the first alkyl group, containing 1 to 8 carbon atoms, including straight or branched alkyl, cyclic alkyl, alkoxyethyl, hydroxyalkyl, hydroxyalkoxyalkyl and straight or branched alkylene. Examples of the other two alkyl groups of trialkyl phosphate include, for example, methyl, ethyl, propyl, butyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, butoxyethyl, isopentyl, neopentyl, isohexyl, isoheptyl, cyclohexyl, propylene, 2-methylpropylene, neopentene, hydroxymethyl, hydroxyethyl, hydroxypropyl or hydroxybutyl. Blends of different trialkyl phosphates may also be used. The three alkyl groups of the trialkyl phosphate may be the same. The trialkyl phosphate is desirably triethyl phosphate (TEP).

[0025] Examples of phosphonates include diethyl (hydroxymethyl) phosphonate, dimethyl methyl phosphonate, and diethyl ethyl phosphonate. Examples of phosphinates include metal salts of organic phosphinates, such as aluminum methylethylphosphinate, aluminum diethylphosphinate, zinc methylethylphosphinate, and zinc diethylphosphinate. Examples of additional halogen-free flame retardant compounds include 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide, ammonium polyphosphate, and combinations thereof.

[0026] For the embodiments provided herein, the transition metal compound is selected from the group consisting of oxides, carboxylates, salts, coordination compounds and combinations thereof, and the transition metal is selected from copper, iron, manganese, cobalt, nickel, zinc and combinations thereof. Examples of transition metal compounds include copper oxide (I), copper oxide (II), copper acetate (II), copper acetate (I), copper butyrate, ethylenediaminetetraacetic acid (EDTA) copper disodium salt, di-μ-hydroxy-bis [(N, N, N', N'-tetramethylethylenediamine) copper II)] chloride, zinc stannate, hydroxy zinc stannate, 2-ethylhexanoic acid manganese (II), dicyclopentadienyl iron (ferrocene) and combinations thereof. Preferably, the transition metal compound is selected from the group consisting of copper oxide (I), copper oxide (II), ethylenediaminetetraacetic acid (EDTA) copper disodium salt and combinations thereof. The transition metal compound of the present disclosure has little effect on the reaction of isocyanate and isocyanate reactive composition. The transition metal compound preferably does not reduce the isocyanurate concentration in the polyurethane foam by 40% or more compared to the same polyurethane foam formulation without the transition metal compound. More preferably, the transition metal compound does not reduce the isocyanurate concentration in the polyurethane foam by 30% or more compared to the same polyurethane foam formulation without the transition metal compound. Most preferably, the transition metal compound does not reduce the isocyanurate concentration in the polyurethane foam by 20% or more compared to the same polyurethane foam formulation without the transition metal compound.

[0027] As discussed in the Examples section below, polyurethane-based foams having transition metal compounds within a given size range produce surprisingly low HCN from pyrolysis. Preferably, the median particle size (D50) of the transition metal compounds used to form the polyurethane-based foams of the present disclosure is from 1 nm to 100 μm. Preferably, the median particle size (D50) of the transition metal compounds used to form the polyurethane-based foams of the present disclosure is from 10 nm to 10 μm. Other preferred values ​​for the median particle size of the transition metal compounds used to form the polyurethane-based foams of the present disclosure include 5 nm to 50 μm and 10 nm to 20 μm.

[0028] For various embodiments, the molar ratio of the number of moles of isocyanate reactive moieties of the isocyanate reactive composition to the number of moles of phosphorus from the halogen-free flame retardant compound is from 70:1 to 1:1. Preferably, the molar ratio of the number of moles of isocyanate reactive moieties to the number of moles of phosphorus from the halogen-free flame retardant compound is from 35:1 to 2:1. Most preferably, the molar ratio of the number of moles of isocyanate reactive moieties to the number of moles of phosphorus from the halogen-free flame retardant compound is from 10:1 to 3:1.

[0029] For the embodiments provided herein, the isocyanate reactive composition may also include a catalyst, a surfactant, a blowing agent or a combination thereof. Other components known in the art may also be included in the isocyanate reactive composition for promoting and / or facilitating the use of the isocyanate reactive composition and the isocyanate compound in the reaction mixture as provided herein for forming a polyurethane-based foam.

[0030] If desired, water may be included in the reaction mixture to promote the reaction and to act as a chemical blowing agent. The amount of water present in the reaction mixture may be 0 to 5 wt. %, based on the total weight of the isocyanate-reactive composition.

[0031] The catalyst may be present in the isocyanate reactive composition in an amount sufficient to provide a reaction mixture having 0.1 to 3.0 wt.% catalyst based on the total weight of the reaction mixture. The catalyst may be selected from the group consisting of: an organic tertiary amine, a tertiary phosphine, potassium acetate, a carbamate-based catalyst, and a combination. The catalyst may also include an organotin compound, as known in the art.

[0032] For various embodiments, the catalyst can be a blowing catalyst, a gelling catalyst, a trimerization catalyst, or a combination thereof. As used herein, blowing catalysts and gelling catalysts can be distinguished by their tendency to favor urea (foaming) reactions in the case of blowing catalysts or urethane (gelling) reactions in the case of gelling catalysts. Trimerization catalysts can be used to promote isocyanurate reactions in the composition.

[0033] Examples of blowing catalysts (e.g., catalysts that may tend to favor the blowing reaction) include, but are not limited to, short chain tertiary amines or oxygen-containing tertiary amines. Amine-based catalysts may not be sterically hindered. For example, blowing catalysts include bis-(2-dimethylaminoethyl) ether; pentamethyldiethylene-triamine, triethylamine, tributylamine, N,N-dimethylaminopropylamine, dimethylethanolamine, N,N,N′,N′-tetramethylethylenediamine, and combinations thereof, and the like. An example of a commercially available blowing catalyst is POLYCAT® available from Evonik. TM 5, and other commercially available blowing catalysts.

[0034] Examples of gelling catalysts (e.g., catalysts that may tend to favor the gelling reaction) include, but are not limited to, organometallic compounds, cyclic tertiary amines and / or long chain amines (e.g., containing several nitrogen atoms), and combinations thereof. Organometallic compounds include organotin compounds, such as tin (II) salts of organic carboxylic acids, such as tin (II) diacetate, tin (II) dioctoate, tin (II) diethylhexanoate, and tin (II) dilaurate, and dialkyltin (IV) salts of organic carboxylic acids, such as dibutyltin diacetate, dibutyltin dilaurate, dibutyltin maleate, and dioctyltin diacetate. Bismuth salts of organic carboxylic acids may also be used as gelling catalysts, such as bismuth octoate. Cyclic tertiary amines and / or long chain amines include dimethylbenzylamine, triethylenediamine, and combinations thereof. An example of a commercially available gelling catalyst is POLYCAT® from Evonik. TM 8 and DABCO TM T-12, and other commercially available gelling catalysts.

[0035] Examples of trimerization catalysts include N,N,N′,N″,N″-pentamethyldiethylenetriamine (PMDETA); N,N′,N″-tris(3-dimethylaminopropyl)hexahydro-S-triazine; N,N-dimethylcyclohexylamine; 1,3,5-tris(N,N-dimethylaminopropyl)-s-hexahydrotriazine; [2,4,6-tris(dimethylaminomethyl)phenol]; potassium acetate, potassium octoate; tetraalkylammonium hydroxides such as tetramethylammonium hydroxide; alkali metal hydroxides such as sodium hydroxide; alkali metal alkoxides such as sodium methoxide, potassium isopropoxide; and alkali metal salts of long-chain fatty acids having 10 to 20 carbon atoms, and combinations thereof, and the like. Some commercially available trimerization catalysts include DABCO, both from Evonik TM TMR-2, TMR-7, DABCO TM K2097; DABCO TM K15, POLYCAT TM 41 and POLYCAT TM 46, and other commercially available trimerization catalysts.

[0036] For various embodiments, a blowing agent may be present in the isocyanate-reactive composition in an amount sufficient to provide a reaction mixture having 1.0 to 15 wt.% of blowing agent based on the total weight of the reaction mixture. As known in the art, the blowing agent may be selected from the group consisting of water, volatile organic substances, dissolved inert gases, and combinations thereof. Examples of blowing agents include hydrocarbons such as butane, isobutane, 2,3-dimethylbutane, n-pentane and isopentane isomers, hexane isomers, heptane isomers and cycloalkanes including cyclopentane, cyclohexane, cycloheptane; hydrofluorocarbons such as HCFC-142b (1-chloro-1,1-difluoroethane), HCFC-141b (1,1-dichloro-1-fluoroethane), HCFC-22 (chlorodifluoromethane), HFC-245fa (1,1,1,3,3-pentafluoropropane), HFC-365mfc (1,1,1,3,3-pentafluorobutane), HFC HFC-227ea (1,1,1,2,3,3,3-heptafluoropropane), HFC-134a (1,1,1,2-tetrafluoroethane), HFC-125 (1,1,1,2,2-pentafluoroethane), HFC-143 (1,1,2-trifluoroethane), HFC 143A (1,1,1-trifluoroethane), HFC-152 (1,1-difluoroethane), HFC-227ea (1,1,1,2,3,3,3-heptafluoropropane), HFC-236ca (1,1,2,2,3,3-hexafluoropropane), HFC 236fa (1,1,1,3,3,3-hexafluoroethane), HFC 245ca (1,1,2,2,3-pentafluoropentane), HFC The invention relates to a foaming agent comprising: a fluorocarbon, ...

[0037] For each embodiment, the surfactant may be present in the isocyanate reactive composition in an amount sufficient to provide a reaction mixture having 0.1 to 10 wt.% of a surfactant based on the total weight of the reaction mixture. Examples of suitable surfactants include silicone-based surfactants and organic-based surfactants. Some representative materials are typically polysiloxane polyoxyalkylene block copolymers, such as those disclosed in U.S. Patents Nos. 2,834,748, 2,917,480; and 2,846,458, the disclosures of which are incorporated herein by reference. Also included are organic surfactants containing polyoxyethylene-polyoxybutylene block copolymers, such as described in U.S. Patent No. 5,600,019, the disclosures of which are incorporated herein by reference as a whole. Other surfactants include polyglycol ethers of long-chain alcohols, long-chain allylic acid sulfates, alkyl sulfonates, tertiary amines or alkanolamine salts of alkylaryl sulfonic acids, and combinations thereof.

[0038] In addition to water, catalysts, blowing agents, surfactants, and combinations thereof, the reaction mixture may also include fillers and other additives. Such other additives are present in the isocyanate-reactive composition in a total amount sufficient to provide a reaction mixture having 0.01 to 3.0 wt.% of other additives (e.g., fillers) based on the total weight of the reaction mixture. The use of other additives for polyurethane foams is also known and can be used with the present disclosure.

[0039] The reaction mixture for forming the polyurethane-based foam of the present disclosure comprises an isocyanate compound having an isocyanate moiety and an isocyanate-reactive compound having an isocyanate-reactive moiety and an aromatic moiety, the aromatic moiety accounting for 5 wt.% to 80 wt.% of the isocyanate-reactive compound based on the total weight of the isocyanate-reactive compound as provided herein. For the embodiments herein, the molar ratio of the isocyanate moiety to the isocyanate-reactive moiety of the reaction mixture can be 1.2:1 to 7:1. Preferably, the molar ratio of the isocyanate moiety to the isocyanate-reactive moiety is 1.5:1 to 5:1. More preferably, the molar ratio of the isocyanate moiety to the isocyanate-reactive moiety is 2:1 to 4:1. Preferably, the isocyanate-reactive moiety of the isocyanate-reactive compound is a hydroxyl moiety, wherein the molar ratio of the isocyanate moiety to the hydroxyl moiety of the reaction mixture is 1.2:1 to 7:1; preferably 1.5:1 to 5:1, and more preferably 2:1 to 4:1.

[0040] The reaction mixture also includes 0.1wt.% to 7.0wt.% phosphorus from halogen-free flame retardant compounds and 0.05wt.% to 14.0wt.% transition metals from transition metal compounds, wherein the wt.% values ​​of phosphorus and transition metals are based on the total weight of isocyanate-reactive compounds, halogen-free flame retardant compounds and transition metal compounds. For each embodiment, halogen-free flame retardant compounds and / or transition metal compounds can be included in the mixture together with isocyanate compounds and / or isocyanate-reactive compounds, wherein when halogen-free flame retardant compounds and transition metal compounds are included together with isocyanate-reactive compounds of the present disclosure, the mixture can provide an isocyanate-reactive composition of the present disclosure. The reaction mixture optionally also includes a catalyst, a surfactant and a blowing agent, each as provided herein, to form a polyurethane-based foam. As discussed herein, a polyurethane-based foam is formed together with the reaction mixture.

[0041] For each embodiment, the number average molecular weight of the isocyanate compound is 150g / mol to 750g / mol. Other number average molecular weight values ​​are also possible. For example, the number average molecular weight of the isocyanate reactive compound can be from a low value of 150, 200, 250 or 300g / mol to a high value of 350, 400, 450, 500 or 750g / mol. In certain embodiments, when the isocyanate compound is an isocyanate reactive compound and a polyisocyanate compound or a polymerized isocyanate compound in excess of moles, the isocyanate prepolymer produced by the reaction under the condition of not causing gelling or curing, the isocyanate prepolymer can have a higher number average molecular weight greater than 750g / mol, and can be calculated by the number average molecular weight and relative mass of each component used to prepare the prepolymer. The number average molecular weight values ​​reported herein are determined by end group analysis, gel permeation chromatography and other methods as known in the art. As known in the art, the isocyanate compound can be monomeric and / or polymeric. In addition, the isocyanate equivalent of the isocyanate compound may be 80 to 400.

[0042] As used herein, the polymeric isocyanate compound contains two or more -NCO groups per molecule. For various embodiments, the polymeric isocyanate compound is selected from aliphatic diisocyanates, alicyclic diisocyanates, aromatic diisocyanates, polyisocyanates, isocyanate prepolymers and combinations thereof. For various embodiments, the number average molecular weight of the isocyanate compound is 150 g / mol to 500 g / mol. In addition, the isocyanate equivalent of the polymeric isocyanate compound can be 80 to 150, preferably 100 to 145, and more preferably 110 to 140.

[0043] Examples of the polymeric isocyanate compounds of the present disclosure may include, but are not limited to, methylene diphenyl diisocyanate (MDI), polymethylene polyphenyl isocyanate containing MDI, polymeric MDI (PMDI), 1,6-hexamethylene diisocyanate (HDI), 2,4- and / or 2,6-toluene diisocyanate (TDI), 1,5-naphthalene diisocyanate (NDI), tetramethylene-1,4-diisocyanate, cyclohexane-1,4-diisocyanate, hexahydrotoluene diisocyanate, hydrogenated MDI (HDI), and the like. 12Suitable isocyanates include methoxyphenyl-2,4-diisocyanate, 4,4′-biphenylene diisocyanate, 3,3′-dimethoxy-4,4′-biphenylene diisocyanate, 3,3′-dimethyldiphenylmethane-4,4′-diisocyanate, 4,4′,4″-triphenylmethane diisocyanate, polymethylene polyphenyl isocyanate, hydrogenated polymethylene polyphenyl polyisocyanate, toluene-2,4,6-triisocyanate and 4,4′-dimethyldiphenylmethane-2,2′,5,5′-tetraisocyanate, methylene biscyclohexyl isocyanate (HMDI), isophorone diisocyanate (IPDI), and combinations thereof. Suitable isocyanates may also include other aromatic and / or aliphatic polyfunctional Isocyanates. Aromatic diisocyanates include those containing phenyl, tolyl, xylyl, naphthyl or diphenyl moieties or combinations thereof, such as trimethylolpropane adducts of xylylene diisocyanate, trimethylolpropane adducts of toluene diisocyanate, 4,4′-diphenyldimethylmethane diisocyanate (MOI), xylylene diisocyanate (XDI), 4,4′-diphenyldimethylmethane diisocyanate, dialkyl diphenylmethane diisocyanate and tetraalkyl diphenylmethane diisocyanate, 4,4′-dibenzyl diisocyanate, 1,3-phenylene diisocyanate, 1,4-phenylene diisocyanate and combinations thereof. Suitable aliphatic polymeric isocyanate compounds include hexamethylene diisocyanate, ester trimer, isophorone diisocyanate trimer, hexamethylene diisocyanate biuret, hydrogenated polymerized methylene diphenyl diisocyanate, hydrogenated methylene diphenyl diisocyanate, hydrogenated MDI, tetramethylxylene diisocyanate (TMXDI), 1-methyl-2,4-diisocyanatocyclohexane, 1,6-diisocyanato-2,2,4-trimethylhexane, 1-isocyanatomethyl-3-isocyanato-1,5,5-trimethylcyclohexane, tetramethoxybutane 1,4-diisocyanate, butane 1,4-diisocyanate, hexane 1,6-diisocyanate, dicyclohexylmethane diisocyanate, cyclohexane 1,4-diisocyanate and combinations thereof. Other polymeric isocyanates Examples of cyanate compounds include additional aliphatic, alicyclic, polycyclic or aromatic, such as hydrogenated xylene diisocyanate (HXDI), p-phenylene diisocyanate (PPDI), 3,3'-dimethyldiphenyl-4,4'-diisocyanate (DDDI), 2,2,4-trimethylhexamethylene diisocyanate (TMDI), isophorone diisocyanate (IPDI), 4,4'-dicyclohexylmethane diisocyanate (H12MDI) and norbornane diisocyanate (NDI). In addition to the isocyanates mentioned above, partially modified polyisocyanates can be used, including uretdione, isocyanurate, carbodiimide, uretonimine, allophanate or biuret structure and combinations thereof, etc.

[0044] In certain embodiments, the viscosity of the isocyanate is 5 to 10,000 mPa·s at 25°C when measured using a Brookfield DVE viscometer. Other viscosity values ​​are also possible. For example, the viscosity of the isocyanate compound measured at 25°C using a Brookfield DVE viscometer can be a low value of 5, 10, 30, 60 or 150 mPa·s to an upper limit of 500, 2500, 5000 or 10,000 mPa·s.

[0045] For the embodiments provided herein, the reaction mixture optionally includes a catalyst, a surfactant, a blowing agent or a combination thereof as discussed herein, wherein these components can be provided in the isocyanate reactive composition discussed herein. The reaction mixture can also include other components known in the art for promoting and / or facilitating a reaction mixture as provided herein, for forming a foam based on polyurethane. It should be understood that the catalyst, surfactant, blowing agent or a combination thereof can be present in any combination of isocyanate reactive compositions and / or isocyanate compounds to reach their respective wt.% values ​​provided herein for the reaction mixture. This is also the case with a reaction mixture with other components known in the art for promoting and / or facilitating the use of reaction mixture components.

[0046] The present disclosure also provides a method for preparing a reaction mixture for producing a polyurethane-based foam. The method may include providing an isocyanate compound having an isocyanate moiety, as discussed herein. The method also includes providing an isocyanate-reactive compound having an isocyanate-reactive moiety and an aromatic moiety, the aromatic moiety accounting for 5 wt.% to 80 wt.% of the isocyanate-reactive compound based on the total weight of the isocyanate-reactive compound. The method also includes providing 0.1 wt.% to 7.0 wt.% of phosphorus from a halogen-free flame retardant compound as discussed herein and 0.05 wt.% to 14.0 wt.% of a transition metal from a transition metal compound as discussed herein, wherein the wt.% values ​​of phosphorus and transition metal are based on the total weight of the isocyanate-reactive compound, the halogen-free flame retardant compound, and the transition metal compound. For these given wt.% values, mixing the isocyanate-reactive composition and the isocyanate compound to form a reaction mixture may include providing a molar ratio of transition metal to phosphorus in the reaction mixture (moles of transition metal: moles of phosphorus) of 0.05:1 to 5:1. The method further includes optionally providing a catalyst, a surfactant, and a blowing agent. The method then includes mixing an isocyanate compound, an isocyanate-reactive compound, a halogen-free flame retardant compound; a transition metal compound; and an optional catalyst, a surfactant, and a blowing agent to form a reaction mixture. For various embodiments, the molar ratio of the isocyanate portion to the isocyanate-reactive portion of the reaction mixture can be 1.2:1 to 7:1.

[0047] Another embodiment of the method also includes mixing a transition metal compound with a carrier to provide a transition metal from a transition metal compound. As used herein, a carrier is a liquid for mixing with a transition metal compound, and the transition metal compound is typically a solid powder for forming a slurry or solution, so that a transition metal (e.g., mixed into an isocyanate reactive composition) from a transition metal compound is provided. Any liquid component used in the reaction mixture for preparing polyurethane foam, whether or not it has isocyanate reactivity, can be used to disperse the transition metal compound. Examples of such carrier liquids include, but are not limited to, polyols, catalysts, surfactants, flame retardant additives, liquid foaming agents, rheology modifiers, liquid dyes, etc. The technician also knows that the transition metal compound can even be directly dispersed into the isocyanate compound for the preparation of polyurethane foam. For the various embodiments, 0.1 wt.% to 7.0 wt.% phosphorus from the halogen-free flame retardant compound (wt.% of phosphorus based on the total weight of the halogen-free flame retardant compound, the halogen-free flame retardant compound, and the transition metal compound) can also be mixed with the isocyanate compound having an isocyanate moiety as discussed herein during the process of preparing the reaction mixture for producing the polyurethane-based foam.

[0048] As previously discussed, the catalyst, surfactant, blowing agent or its combination for the reaction mixture can be optionally provided in the isocyanate reactive composition as discussed herein. It is also possible to mix the other components provided herein with the isocyanate reactive composition and the isocyanate compound to form a reaction mixture. It should be understood that the catalyst, surfactant, blowing agent or its combination can exist with any combination of isocyanate reactive composition and / or isocyanate compound to reach the wt.% value provided for the reaction mixture separately herein. This is also the case with the reaction mixture of other components known in the art for promoting and / or facilitating the use of isocyanate reactive composition and isocyanate compound in the reaction mixture.

[0049] The method for preparing a reaction mixture for producing a polyurethane-based foam can be achieved by any process technology known in the art. Generally, the polyurethane-based foam of the present disclosure can be produced by a discontinuous or continuous process, including processes commonly referred to as discontinuous plate processes (DCP) and continuous lamination, in which the foaming reaction and subsequent curing are carried out in a mold or on a conveyor. The method provided herein can be performed at a temperature of 15° C. to 80° C. The mixing pressure of the method can include a value of 80 kPa to 25,000 kPa. Mixing can be performed using a mixing device known in the art. The density of the resulting foam can be 10 kg / m 3 or higher, preferably 15kg / m 3or higher, more preferably 25kg / m 3 or higher, most preferably 35kg / m 3 or higher, and at the same time usually 200kg / m 3 or less, preferably 100 kg / m 3 or less, more preferably 70kg / m 3 or less, and most preferably 50 kg / m 3 or smaller.

[0050] The polyurethane-based foams of the present disclosure provide low smoke generation and high thermal stability as determined according to ASTM E662 "Test Method for Specific Optical Density of Smoke Generated by Solid Materials". Lower maximum specific optical density (Max Ds) values ​​mean lower smoke generation. Lower mass loss % values ​​mean higher thermal stability. Max Ds may be 400 or less, preferably 200 or less, more preferably 100 or less, and also most preferably 50 or less. Mass loss % may be 50% or less, preferably 45% or less, more preferably 40% or less, and also most preferably 35% or less.

[0051] The polyurethane-based foams of the present disclosure may have low thermal conductivity in applications such as for building insulation. The thermal conductivity of rigid foams is represented by the K factor. The K factor is a measure of insulation performance. The K factor of the prepared foam may be 30.0 mW / m·K or less, preferably 27.0 mW / m·K or less, more preferably 24.0 mW / m·K or less, and most preferably 22.0 mW / m·K or less. Thermal conductivity (K factor) is measured using ASTM C-518-17 at an average temperature of 75°F.

[0052] Applications of polyurethane-based foams produced by the present disclosure are those known in the industry. For example, polyurethane-based foams can be used for insulation materials used in building walls and roofs, garage doors, transport trucks and rail cars, and cold storage facilities. The polyurethane-based foams disclosed herein can have a combination of properties desired for these applications. For example, the polyurethane-based foams disclosed herein can advantageously provide desired low thermal conductivity, smoke density, thermal stability, and improved combustion characteristics while reducing HCN and CO emissions.

[0053] Some embodiments of the present disclosure will now be described in detail in the following examples.

[0054] Examples

[0055] In the examples, various terms and names of materials are used, including, for example, the following:

[0056] Material

[0057] Materials used in Examples and / or Comparative Examples include the following.

[0058] Polyol A is a polyester polyol (aromatic polyester polyol from terephthalic acid, polyethylene glycol and diethylene glycol) with a hydroxyl value of 220 mg KOH / g, a functionality of 2, and a total aromatic content of 14.8 wt.%, from Dow

[0059] Polyol B is a polyester polyol (aromatic polyester polyol from terephthalic acid, polyethylene glycol, glycerol and diethylene glycol) with a hydroxyl value of 315 mg KOH / g, a functionality of 2.4 and a total aromatic content of 17.4 wt.% from Dow

[0060] Triethyl phosphate (TEP) is a flame retardant from LANXESS.

[0061] Fyrolflex TM Resorcinol bis(diphenyl phosphate) (RDP) is a flame retardant from ICL. Industrial Products.

[0062] Diethyl (hydroxymethyl)phosphonate (DEHMP) is a flame retardant from Tokyo Chemical Industry Co., Ltd.

[0063] POLYCAT TM 5 is a catalyst from Evonik Industries AG.

[0064] POLYCAT TM 46 is a catalyst from Evonik Industries AG.

[0065] The surfactant was a silicone rigid foam surfactant from Evonik Industries AG.

[0066] The water is deionized water having a specific resistivity of 10 MΩ×cm (million ohms) at 25°C.

[0067] Cyclopentane (c-Pentane) is a blowing agent from Sigma-Aldrich.

[0068] PAPI TM580N is a polymethylene polyphenyl isocyanate from Dow Inc. containing methylene diphenyl diisocyanate (MDI) and having 30.8% isocyanate.

[0069] Copper disodium ethylenediaminetetraacetate (CuEDTA) was from Fluka.

[0070] Copper(II) 2-ethylhexanoate (CuEH) was from Sigma-Aldrich.

[0071] Copper (I) oxide (Cu2O), powder, size ≤7 μm, 97% from Sigma-Aldrich.

[0072] Copper(II) oxide (CuO), powder, size ≤10 μm, 98% from Sigma-Aldrich.

[0073] Copper(II) oxide (CuO), powder, size 10 nm, 98% from US Research Nanomaterials, Inc.

[0074] Copper(II) oxide (CuO), powder, size 40 nm, 98% from Research Nanomaterials, USA. Biscyclopentadienyl iron (ferrocene) from Fluka.

[0075] Preparation of polyurethane-based foams for Examples (Ex) and Comparative Examples (C Ex)

[0076] The following components were used in the reaction mixture to form polyurethane-based foams for Examples (Ex.) 1-17 and Comparative Examples (C Ex.) AF. The amount of each component is given in parts by weight (PBW) based on the total weight of the reaction mixture used to form the polyurethane-based foam. The amount of "transition metal compound" is shown in Table 1, and the composition of the "transition metal compound" for each example and comparative example is shown in Tables 2 to 5.

[0077] Table 1 - Reaction mixture of polyisocyanurates Ex and C Ex for polyurethane-based foams (isocyanate index 387)

[0078] Components PBW Isocyanate reactive compositions Polyester polyol A 16.33 Polyester polyol B 5.44 Phosphorus in Phosphorus Compounds 0.3 to 1.5 <![CDATA[POLYCAT TM 5 Catalyst]]> 0.26 <![CDATA[POLYCAT TM 46 Catalyst]]> 0.49 Surfactants 0.77 water 0.20 Cyclopentane 5.38 Transition metals from transition metal compounds 0 to 3.0 Isocyanate <![CDATA[PAPI TM 580N]]> 67.28

[0079] Prepare polyurethane-based foam as follows. For each Ex and C Ex, the components of the isocyanate-reactive composition (except the cyclopentane and transition metal compounds provided in Table 1) are mixed at 2000rpm for 1 minute (min) in a plastic beaker with a rotary mixer. The transition metal compound of each Ex and C Ex is directly mixed with the isocyanate-reactive composition at 2000rpm for 1min, except for the following transition metal compounds. For CuEH, CuEH is first dissolved in TEP, and then mixed with the remaining components of the isocyanate-reactive composition. Then, the cyclopentane of each Ex and C Ex is directly mixed with the isocyanate-reactive composition. Next, the isocyanate-reactive composition and isocyanate are mixed again at 3000rpm for 4 seconds (s) in a beaker. After mixing, the contents in the beaker are immediately poured into a mold (300 millimeters (mm) x200mm x 50mm) preheated to 60°C. After curing at 60°C for 20 minutes, the polyurethane-based foam is taken out from the mold. The core density of the molded polyurethane-based foam is approximately 40 kg / m 3 .

[0080] Flue gas composition analysis

[0081] Method 1 - Pyrolysis / GC

[0082] Pyrolysis tests were performed using a Frontier Labs 2020D pyrolyzer mounted on an Agilent 6890GC with an FID detector. Approximately 200-250 μg of sample was weighed into a Frontier labs silica gel lined stainless steel cup. Pyrolysis was performed in single shot mode by placing the sample cup in an oven and analyzing it for 2 min under air conditions at 600 ° C and then for another 2 min under helium conditions. A micro cryogenic trap (MCT) was used to capture volatile products emitted from the sample at the top of the separation column. A 10mx 0.32mm ID x 5μm PoraBond Q column from Agilent was used to achieve separation with HP-1 (10mx 0.53mm x 2.65um) as a guard column. The back inlet pressure was used for backflush purposes (0.5mx0.53mm guard column, using the back inlet as its top pressure tee in the PoraBond Q and HP-1 columns). HCN was detected on the backside FID detector. HCN concentration comparison was performed using the HCN peak area normalized by sample weight. The relative HCN content of the sample containing transition metals was defined as the ratio of its normalized HCN peak area divided by the normalized HCN peak area of ​​the comparative control example without transition metals.

[0083] GC conditions: front inlet: 300°C; 1:1 split injector; ramp pressure: 4.9psi for 1.5min, then increased to 3.1psi at 50psi / min; back inlet: 4psi; GC oven: 40°C for 3min, increased to 240°C at 30°C / min; FID: 250°C, H2 flow rate: 40mL / min, air flow rate: 450mL / min, tail gas (N2): 30mL / min, 50Hz.

[0084] 2-NBS / FTIR

[0085] The NBS smoke chamber test protocol was performed according to ISO 5659:1994 (Plastics-Smoke Generation-Part 2: Determination of Optical Density by a Single Chamber Test). The samples were exposed to 50 kW / m 2 The test was carried out for 20 minutes in flame exposure mode at an irradiance of . The combustion products were analyzed using a Fourier transform infrared (FTIR) spectrometer. Gas sampling for toxicity measurement began at the beginning of exposure and continued until the end of the test period. The maximum detected concentration (in parts per million) and the mass loss % of the sample were reported as (initial mass-final mass) / nominal mass*100%. The nominal mass of the sample is the total mass of the foam sample with dimensions of 3"x3"x1". The relative HCN content or CO content of the sample containing transition metals is defined as the ratio of the maximum HCN or maximum CO concentration normalized by the maximum HCN or maximum CO concentration of the comparative control example without transition metals.

[0086] NBS smoke density and mass loss % measurements

[0087] NBS smoke density measurements were performed according to ASTM E-662 (Standard Test Method for Specific Optical Density of Smoke Generated by Solid Materials). The samples were exposed to 25 kW / m 2 The test was conducted for 10 minutes in flame exposure mode under an irradiance of s，max ) and the mass loss % of the sample is reported as (initial mass - final mass) / nominal mass*100%. The nominal mass of the sample is the total mass of the foam sample with dimensions of 3"x3"x1".

[0088] Relative isocyanurate content measurement

[0089] Attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR) measurements were performed on a Nicolet iS50 FT-IR instrument with a SMART iTX single reflection diamond ATR. -1 Spectral range: 4 cm -1 Sixteen scans were collected at a resolution of 1000 nm. A rectangular cross section (10 mm x 60 mm) was cut from the center of the molded polyurethane-based foam sample. The cross section was tested three times and the three measurements of the characteristic peaks were averaged. The relative isocyanurate content was defined as the height of the characteristic peak of the isocyanurate group (about 1409 cm -1 ) and the characteristic peak height of phenyl group (about 1595cm -1 ) is a ratio normalized by the peak height ratio of a comparative control example not containing a transition metal.

[0090] result

[0091] Table 2 shows that the HCN generated by pyrolysis / GC is significantly reduced (relative HCN concentration < 0.70) while maintaining the excellent smoke density and thermal stability of the polyurethane-based foam (Max Ds <= 45, mass loss value <= 35%, and relative isocyanurate content >= 0.60).

[0092] Table 2

[0093]

[0094] As shown in Tables 3 and 4 , significant reduction in HCN generation from pyrolysis / GC, excellent smoke density, and isocyanurate content were achieved using different phosphorus compounds.

[0095] Table 3

[0096] C EX D Ex 10 Transition Metal Additives none <![CDATA[Cu2O]]> Transition metal ion wt.% 0 0.5 Source of P DEHMP DEHMP P wt.% 0.65 0.65 Transition metal / P molar ratio 0 0.38 Relative HCN concentration 1.00 0.13 Relative isocyanurate content 1.00 1.00 Max Ds(ASTM E-662) 30 34 Mass loss% (ASTM E-662) 27.1％ 27.1％

[0097] Table 4

[0098] C EX E Ex11 Transition Metal Additives none <![CDATA[Cu2O]]> Transition metal ion wt.% 0 0.5 Source of P RDP RDP P wt.% 0.65 0.65 Transition metal / P molar ratio 0 0.38 Relative HCN concentration 1.00 0.24 Relative isocyanurate content 1.00 1.05 Max Ds(ASTM E-662) 29 55 Mass loss% (ASTM E-662) 18.6％ 23.7％

[0099] As shown in Table 5 , a significant reduction in HCN production from pyrolysis / GC can be achieved by adding different types of transition metal compounds.

[0100] Table 5

[0101]

[0102] As shown in Table 6 , a significant reduction in HCN production from pyrolysis / GC can be achieved by adding transition metal additives of different sizes.

[0103] Table 6

[0104] C EX A Ex 16 Ex 17 Ex 18 Transition Metal Additives none CuO CuO CuO Average particle size of additives none 10μm 40nm 10nm Transition metal ion wt.% 0 0.5 0.5 0.5 Source of P TEP TEP TEP TEP P wt.% 0.65 0.65 0.65 0.65 Transition metal / P molar ratio 0 0.38 0.38 0.38 Relative HCN concentration 1.00 0.24 0.12 0.28 Relative isocyanurate content 1.00 0.65 0.76 0.79

[0105] As shown in high heat flux exposure (50kw / m 2 ) conditions (Table 7), a significant reduction in HCN and CO was observed for polyurethane-based foams containing all concentrations of Cu2O. Surprisingly, more effective HCN and CO reduction and higher carbon residue rates were achieved at 0.25 wt.% copper concentration. Using the copper compound CuEH, which is soluble in the isocyanate-reactive composition, HCN emissions were higher than the control (CEX A).

[0106] Table 7

[0107] C EX A C EX F Ex 2 Ex 3 Ex 4 Transition Metal Additives none HkDJ <![CDATA[Cu2O]]> <![CDATA[Cu2O]]> <![CDATA[Cu2O]]> Transition metal ion wt.% 0 0.25 0.25 0.5 1.0 Type of P TEP TEP TEP TEP TEP P wt.% 0.65 0.65 0.65 0.65 0.65 Transition metal / P molar ratio 0 0.19 0.19 0.38 0.75 Relative maximum HCN concentration 1.00 1.25 0.27 0.84 0.78 Relative maximum CO concentration 1.00 0.92 0.17 0.71 0.72 Relative isocyanurate content 1.00 0.67 0.86 0.85 0.82 Max Ds 46 193 51 49 40 Mass loss% 49.1％ 67.8％ 42.4％ 47.5％ 52.5％ K factor (mW / m·K) 20.8 20.9 20.7 21.6 20.9

Claims

1. An isocyanate-reactive composition for forming a polyurethane-based foam, consisting of: an isocyanate-reactive compound having an isocyanate-reactive portion and an aromatic portion, wherein the aromatic portion is 5 wt. % to 80 wt. % of the isocyanate-reactive compound based on the total weight of the isocyanate-reactive compound; A combustion regulator composition, which consists of: 0.1 wt.% to 7.0 wt.% phosphorus from a halogen-free flame retardant compound; and 0.05 wt.% to 14.0 wt.% of a transition metal from a transition metal compound, wherein the wt.% of the transition metal and the wt.% of the phosphorus are each based on the total weight of the isocyanate-reactive compound, the halogen-free flame retardant compound, and the transition metal compound, wherein the median particle size of the transition metal compound is 10 nm to 20 μm; wherein the molar ratio of the transition metal to the phosphorus of the combustion moderator composition is from 0.15:1 to 5:1, and wherein the transition metal compound is selected from the group consisting of oxides, salts, coordination compounds, and combinations thereof, and the transition metal is copper; Optionally, water, a catalyst, a surfactant, a blowing agent, or a combination thereof; and Optionally, fillers.

2. The isocyanate-reactive composition of claim 1, wherein the molar ratio of the transition metal to the phosphorus of the combustion moderator composition is from 0.15:1 to 3:1; and / or wherein the transition metal compound is a carboxylate.

3. The isocyanate reactive composition of claim 1, wherein the halogen-free flame retardant compound is selected from the group consisting of phosphate esters, phosphonate esters, phosphinate esters, and combinations thereof.

4. The isocyanate-reactive composition of claim 1 , wherein the transition metal compound is selected from copper (I) oxide, copper (II) oxide, copper (II) acetate, copper (I) acetate, copper butyrate, ethylenediaminetetraacetic acid (EDTA) copper disodium salt, di-μ-hydroxy-bis[(N,N,N′,N′-tetramethylethylenediamine)copper II)] chloride; and / or wherein the isocyanate-reactive composition comprises 0.25 wt.% of a transition metal from a transition metal compound.

5. The isocyanate-reactive composition of claim 1, wherein the transition metal compound is selected from the group consisting of copper (I) oxide, copper (II) oxide, ethylenediaminetetraacetic acid (EDTA) copper disodium salt, and combinations thereof.

6. The isocyanate-reactive composition according to any one of claims 1 to 5, wherein the median particle size of the transition metal compound is from 10 nm to 10 μm.

7. A reaction mixture for forming a polyurethane-based foam, consisting of: an isocyanate compound having an isocyanate moiety; An isocyanate-reactive compound having an isocyanate-reactive portion and an aromatic portion, wherein the aromatic portion accounts for 5 wt.% to 80 wt.% of the isocyanate-reactive compound based on the total weight of the isocyanate-reactive compound. 0.1 wt.% to 7.0 wt.% phosphorus from a halogen-free flame retardant compound and 0.05 wt.% to 14.0 wt.% transition metal from a transition metal compound, wherein the wt.% values ​​of phosphorus and the transition metal are based on the total weight of the isocyanate-reactive compound, the halogen-free flame retardant compound, and the transition metal compound, wherein the molar ratio of the transition metal to the phosphorus is from 0.15:1 to 5:1, and wherein the transition metal compound is selected from the group consisting of oxides, salts, coordination compounds, and combinations thereof, and the transition metal is copper, wherein the median particle size of the transition metal compound is from 10 nm to 20 μm; and Optionally, water, a catalyst, a surfactant, a blowing agent, or a combination thereof; and Optionally, fillers.

8. The reaction mixture of claim 7, wherein the molar ratio of the isocyanate moieties to the isocyanate-reactive moieties of the reaction mixture is from 1.2:1 to 7:1; and / or wherein the transition metal compound is a carboxylate.

9. A polyurethane-based foam formed using the reaction mixture according to any one of claims 7-8.

10. A process for preparing a reaction mixture for producing a polyurethane-based foam, the process comprising: providing an isocyanate compound having an isocyanate moiety; Providing an isocyanate reactive composition according to any one of claims 1 to 6; optionally providing a catalyst, a surfactant, a blowing agent, or a combination thereof; and The isocyanate compound, the isocyanate-reactive composition, and the optional catalyst, surfactant, blowing agent, or combination thereof are mixed to form the reaction mixture, wherein the molar ratio of the isocyanate portion to the isocyanate-reactive portion of the reaction mixture is from 1.2:1 to 7:1.

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