Foam formulation

Abstract

The embodiments disclosed herein relate to foam formulations comprising high-hydroxyl polyether polyols, low-hydroxyl polyether polyols, ammonium polyphosphate, alkaline earth metal carbonates, blowing agents, and isocyanates.

Description

Technical Field

[0001] The implementation scheme disclosed herein involves foam formulations. Background Technology

[0002] Foam is a dispersion in which gas is dispersed and / or generated in a liquid, solid, or gel material. Foam can be formed through a chemical reaction of polyols and isocyanates. Foam can be used in many diverse applications, including electric vehicles (EVs) or stationary battery pack modules and / or battery pack assemblies, as well as other applications. Summary of the Invention

[0003] This disclosure provides various embodiments, including the following. In some embodiments, this disclosure relates to a rigid foam formulation comprising: a high-hydroxyl-number polyether polyol having an average hydroxyl number of 350 mg KOH / g to 1,900 mg KOH / g and an average hydroxyl functionality of 1.5 to 8; a low-hydroxyl-number polyether polyol having an average hydroxyl number of 7 mg KOH / g to 70 mg KOH / g and an average hydroxyl functionality of 1.5 to 8; ammonium polyphosphate; an alkaline earth metal salt; a blowing agent; and an isocyanate.

[0004] The foregoing description of this invention is not intended to describe every disclosed embodiment or every implementation thereof. The following description illustrates exemplary embodiments in more detail. Throughout this application, guidance is provided by a list of examples, which may be used in various combinations. In each case, the enumerated list serves only as a representative group and should not be construed as an exclusive list. Detailed Implementation

[0005] This document discloses foam formulations. Foam formulations as disclosed herein can be cured to manufacture foam products having one or more desired properties (i.e., desired flame retardancy ratings). Foam formulations as disclosed herein can be rigid foam formulations, for example, that can be cured to manufacture rigid foam products. For example, foam products (thickness ≤10 mm) can provide a UL-94 vertical flammability rating of V-0, V-1, or V-2; and a UL-94 horizontal flammability rating of HBF. UL-94 is a known standard for flammability testing (UL is equivalent to Underwriters Laboratories). UL-94 in a vertical test sample arrangement provides ratings including V-0 (best performance), V-1 (performance below V-0), V-2 (performance below V-1), and unacceptable (performance below V-2). Similarly, in a horizontal test sample arrangement, HBF (best performance), HF-1 (performance below HBF), HF-2 (performance below HF-1), and unacceptable (performance below HF-2) are produced.

[0006] Surprisingly, foam formulations as disclosed herein can be cured to manufacture foam products that provide a UL-94 vertical flammability rating of V-0, V-1, or V-2, while also offering many other desirable properties, such as specific density values, specific modulus of elasticity, specific elongation at break and / or specific tensile strength, and specific resistivity compared to other foams. Such foam products can be used in numerous applications, such as electric vehicle (EV) battery modules or battery pack assemblies, among others.

[0007] The foam formulations disclosed herein include high-hydroxyl-number polyether polyols and low-hydroxyl-number polyether polyols. As used herein, high-hydroxyl-number polyether polyols have a higher average hydroxyl number compared to low-hydroxyl-number polyether polyols. As used herein, "polyol" means a molecule having an average of more than 1.0 hydroxyl groups per molecule, for example, an average hydroxyl functionality greater than 1.0.

[0008] High hydroxyl number polyether polyols can have an average hydroxyl number (value) ranging from 350 mg KOH / g to 1,900 mg KOH / g. This includes all individual values ​​and sub-ranges from 350 mg KOH / g to 1,900 mg KOH / g; for example, high hydroxyl number polyether polyols can have an average hydroxyl number ranging from a lower limit of 350 mg KOH / g, 450 mg KOH / g, or 500 mg KOH / g to an upper limit of 1,900 mg KOH / g, 1,500 mg KOH / g, 1,100 mg KOH / g, or 900 mg KOH / g. The average hydroxyl number can be determined according to ASTM D4274-21.

[0009] High hydroxyl number polyether polyols may have an average hydroxyl functionality of 1.5 to 8. This includes all individual values ​​and sub-ranges from 2 to 8; for example, high hydroxyl number polyether polyols may have an average hydroxyl functionality ranging from a lower limit of 1.5, 2, 2.5, or 2.7 to an upper limit of 8, 6, 5, or 4. One or more embodiments specify that the high hydroxyl number polyether polyol has an average hydroxyl functionality of 3.0.

[0010] The average hydroxyl equivalent of a polyol, expressed in g / mol OH (e.g., g / mol of OH, i.e., hydroxyl end groups), can be calculated by dividing 56110 by the average number of hydroxyl groups from ASTM D4274-21. High hydroxyl number polyether polyols can have hydroxyl equivalents from 30 g / mol OH to 160 g / mol OH. This includes all individual values ​​and sub-ranges from 30 g / mol OH to 160 g / mol OH; for example, high hydroxyl number polyether polyols can have hydroxyl equivalents from a lower limit of 30 g / mol, 50 g / mol, or 65 g / mol to an upper limit of 160 g / mol OH, 120 g / mol OH, or 100 g / mol OH.

[0011] High hydroxyl number polyether polyols can be glycerol alkoxylated polyether polyols. As used herein, "glycerol alkoxylated polyether polyol" refers to a compound produced via a reaction of glycerol as an initiator molecule that reacts with an epoxide. Examples of epoxides may include ethylene oxide, propylene oxide, and / or butyl oxide. One or more epoxides can be used to produce high hydroxyl number polyether polyols. One or more embodiments specify that the high hydroxyl number polyether polyol is produced via a reaction of glycerol and propylene oxide. One or more embodiments specify that the high hydroxyl number polyether polyol does not contain structural units derived from ethylene oxide or butyl oxide, i.e., the high hydroxyl number polyether polyol is a glycerol propoxylated polyether polyol. Instead of glycerol, many other initiator molecules can be used for high hydroxyl number polyether polyols. Other initiator molecules include trimethylolpropane, pentaerythritol, erythritol, and sorbitol, etc. For the purposes of this disclosure, high hydroxyl number polyether polyols may also be one or more of the initiator molecules discussed herein. High hydroxyl number polyether polyols can be blends of two or more high hydroxyl number polyether polyols discussed in this article.

[0012] High hydroxyl number polyether polyols can be prepared using known equipment, reaction conditions, and reaction components. High hydroxyl number polyether polyols are commercially available. For example, many commercially available high hydroxyl number polyether polyols are available from Dow Chemical Company under trade names such as VORANOL, VORATRON, SPECFLEX, VORAFORCE, VORALAST, SPECFIL, VORACOR, and VORALUX.

[0013] Based on 100% by weight of the foam formulation, high hydroxyl polyether polyols may comprise 10% to 30% by weight of the foam formulation. This includes all individual values ​​and sub-ranges from 10% to 30% by weight; for example, based on 100% by weight of the foam formulation, high hydroxyl polyether polyols may comprise a lower limit of 10%, 12%, or 15% by weight to an upper limit of 30%, 28%, or 25% by weight.

[0014] As mentioned, the foam formulations disclosed herein contain low-hydroxyl-number polyether polyols. Low-hydroxyl-number polyether polyols may have an average hydroxyl number (value) ranging from 7 mg KOH / g to 70 mg KOH / g as determined according to ASTM D4274-21. This includes all individual values ​​and sub-ranges from 7 mg KOH / g to 70 mg KOH / g; for example, low-hydroxyl-number polyether polyols may have an average hydroxyl number ranging from a lower limit of 7 mg KOH / g, 15 mg KOH / g, or 20 mg KOH / g to an upper limit of 70 mg KOH / g, 60 mg KOH / g, or 50 mg KOH / g.

[0015] Low hydroxyl number polyether polyols may have an average hydroxyl functionality of 1.5 to 8. This includes all individual values ​​and sub-ranges from 1.5 to 8; for example, low hydroxyl number polyether polyols may have an average hydroxyl functionality ranging from a lower limit of 1.5 or 1.8 to an upper limit of 8, 6, 5, or 4. One or more embodiments specify that the low hydroxyl number polyether polyol has an average hydroxyl functionality of 2.0.

[0016] The average hydroxyl equivalent of a polyol, expressed in g / mol OH (e.g., g / mol of OH end groups), can be calculated by dividing 56110 by the average number of hydroxyl groups from ASTM D4274-21. Low hydroxyl number polyether polyols can have an average hydroxyl equivalent of 801 g / mol OH to 8014 g / mol OH. This includes all individual values ​​and sub-ranges from 801 g / mol OH to 8014 g / mol OH; for example, low hydroxyl number polyether polyols can have an average equivalent of 801 g / mol OH, 1,000 g / mol OH, 1,500 g / mol OH, or 1,750 g / mol OH to an upper limit of 8014 g / mol OH, 7,000 g / mol OH, 6,000 g / mol OH, or 4,000 g / mol OH, or 2,500 g / mol OH, or 2,250 g / mol OH.

[0017] Low hydroxyl number polyether polyols may be alkoxylated polyether polyols. One or more epoxides may be used to manufacture low hydroxyl number polyether polyols. One or more embodiments specify that the low hydroxyl number polyether polyol is manufactured via a reaction of a diol and propylene oxide. One or more embodiments specify that the low hydroxyl number polyether polyol is end-capped with ethylene oxide. The low hydroxyl number polyether polyol may be a blend of two or more low hydroxyl number polyether polyols discussed herein. One or more embodiments specify that the low hydroxyl number polyether polyol is a bifunctional polyether polyol.

[0018] Furthermore, low-hydroxyl-number polyether polyols can be end-capped with ethylene oxide oligomers or polymers (EO-terminated), which can alter the modulus, elongation properties, and / or toughness compared to rigid foams of similar density. EO-terminated low-hydroxyl-number polyether polyols can have an ethylene oxide (EO) content of 3% to 80%, 3% to 50%, or 3% to 30% by weight percentage (wt%). In some cases, low-hydroxyl-number polyether polyols may contain EO-terminated polypropylene oxide with an EO content ranging from 3% to 80% or 3% to 50% by weight.

[0019] Low hydroxyl number polyether polyols can be prepared using known equipment, reaction conditions, and reaction components. Low hydroxyl number polyether polyols are commercially available. For example, many commercially available low hydroxyl number polyether polyols are available from Dow Chemical Company under trade names such as VORANOL, VORATRON, SPECFLEX, VORAFORCE, VORALAST, SPECFIL, VORACOR, and VORALUX.

[0020] Based on 100% by weight of the foam formulation, low hydroxyl polyether polyols may comprise 10% to 30% by weight of the foam formulation. This includes all individual values ​​and sub-ranges from 10% to 30% by weight; for example, based on 100% by weight of the foam formulation, low hydroxyl polyether polyols may comprise a lower limit of 10%, 12%, or 15% by weight to an upper limit of 30%, 28%, or 25% by weight.

[0021] The foam formulations disclosed herein contain a blowing agent. The blowing agent reacts under foaming reaction conditions to produce gas. The blowing agent may be referred to as a chemical blowing agent. Examples of blowing agents include water, formic acid, hydrocarbons, acids, volatile organic compounds, etc. Physical blowing agents include gases such as chlorofluorocarbons (CFCs), hydrochlorofluorocarbons (HCFCs), acetone, nitrogen, air, carbon dioxide, etc., and combinations thereof. One or more embodiments specify that the blowing agent is water. The foam formulations disclosed herein may contain one or more of chemical and physical blowing agents. The blowing agent may be sufficient to provide 0.3 g / cm³ of foam. 3 Up to 0.75 g / cm 3 The amount of the mixture of the density of the isocyanate is added to the isocyanate reactive component (i.e., the polyol side) or the isocyanate component and / or added during the mixing of polyols and isocyanates.

[0022] Based on 100% by weight of the foam formulation, the blowing agent may account for 0.01% by weight to 5% by weight of the foam formulation. This includes all individual values ​​and sub-ranges from 0.01% by weight to 5% by weight; for example, based on 100% by weight of the foam formulation, the blowing agent may be a lower limit of 0.01% by weight, 0.05% by weight, or 0.1% by weight to a higher limit of 4% by weight, 2% by weight, 1.5% by weight, 1.0% by weight, 0.8% by weight, or 0.5% by weight.

[0023] The foam formulation may contain one or more polyester polyols, which are produced by reacting one or more carboxylic diacids with a polyol having an OH functionality of 2 to 4. Suitable carboxylic acids include aromatic diacids or anhydrides, such as phthalic acid, phthalic anhydride, isophthalic acid, terephthalic acid, methyl phthalate, dimethyl terephthalate, trimellitic anhydride, pyromellitic dianhydride, or mixtures thereof; and C4 to C12 aliphatic diacids. Suitable polyols for forming the polyester include one or more alkylene glycols or polyalkylene glycols having a hydroxyl functionality of 2 to 4, such as ethylene glycol, 1,2-propanediol or 1,3-propanediol, 1,4-butanediol, 1,6-hexanediol, diethylene glycol, glycerol, etc. Examples of polyester polyols include polyesters of phthalic anhydride and diethylene glycol, and polyesters of C4 to C12 diacids (such as succinic acid or adipic acid) and diethylene glycol. Polyester polyols may have an average number of hydroxyl groups in the range of 100 mg KOH / g to 500 mg KOH / g, 150 mg KOH / g to 450 mg KOH / g, or 200 mg KOH / g to 450 mg KOH / g, as determined according to ASTM D4274-21. The isocyanate reactive component may include one or more polyester polyols in weight percentages (wt%) ranging from 10 wt% to 40 wt%, 15 wt% to 35 wt%, or 15 wt% to 30 wt%.

[0024] The isocyanate reactive component may include one or more organosilicon polyols having at least two reactive hydroxyl groups. The organosilicon polyol may contain siloxane bonds (Si-O-Si) within its main chain, and in some cases may also contain divalent alkyl groups separating the siloxane units. The organosilicon polyol may have the general formula HO-R1-Si(R2)2-[O-Si(R2)2]n-R1-OH, wherein each R1 is independently a linking group having 0 to 18 carbon atoms; each R2 is independently a group having 2 to 18 carbon atoms, such as an alkyl or hydroxyalkyl group; and wherein n is 10 to 20.

[0025] The isocyanate reactive component may include one or more organosilicon polyols in the range of 10% to 40% by weight, 15% to 35% by weight, or 15% to 30% by weight, by weight percentage (wt%).

[0026] The isocyanate reactive component may include one or more aliphatic polyols having at least two reactive hydroxyl groups. Aliphatic polyols include natural and synthetic polyester polyol derivatives, including products generated by reacting a polyol with one or more hydroxy fatty acids having 10 to 20 carbon atoms, such hydroxy fatty acids including hydroxydecanoic acid, hydroxylauric acid, hydroxymyristic acid, hydroxypalmitic acid, hydroxyheptadecanoic acid, hydroxystearic acid, hydroxyeicosanoic acid, ricinoleic acid, etc. For example, aliphatic polyols include triglycerides containing a portion of hydroxy fatty acids, such as castor oil or derivatives thereof, and / or polyols made from epoxidized or hydroformylated natural oils such as soybean oil, cashew nut shell extract (i.e., CNSL). Aliphatic polyols may have an average hydroxyl equivalent in the range of 30 g / mol OH to 2500 g / mol OH or 30 g / mol OH to 2000 g / mol OH.

[0027] The isocyanate reactive component may include one or more aliphatic polyols in weight percentages (wt%) ranging from 2% to 45% wt%, 5% to 35% wt%, 5% to 25% wt%, 5% to 20% wt%, or 5% to 10% wt%.

[0028] The foam formulation disclosed herein contains ammonium polyphosphate. Ammonium polyphosphate can be referred to as a halogen-free flame retardant or an ionic salt additive. Ammonium polyphosphate corresponds to CAS Registry No. 68333-79-9. Based on the total weight of ammonium polyphosphate, it may have a phosphorus content of 20% to 50% by weight. Ammonium polyphosphate may have a phosphorus content of approximately 1.9 g / cm³. 3 (range between 1.5g / cm) 3 Up to 2.5g / cm 3 The density of ammonium polyphosphate is as follows. Ammonium polyphosphate can have an average particle size (mass median diameter, i.e., d50) of 15 to 17 micrometers (ranging from 5 to 200 micrometers). Ammonium polyphosphate can be a crystalline phase II (commonly referred to as phase II APP or APP phase II) with a degree of polymerization greater than 700, and can have a decomposition temperature greater than 250°C.

[0029] Based on 100% by weight of foam formulation, ammonium polyphosphate may comprise from 0.5% by weight to 30% by weight of the foam formulation. This includes all individual values ​​and sub-ranges from 0.5% by weight to 30% by weight; for example, based on 100% by weight of foam formulation, ammonium polyphosphate may be from a lower limit of 0.5% by weight, 1% by weight, 3% by weight, 5% by weight, 7% by weight, or 10% by weight to an upper limit of 30% by weight, 25% by weight, 20% by weight, or 18% by weight.

[0030] The foam formulations disclosed herein contain alkaline earth metal salts, preferably but not limited to alkaline earth metal carbonates. Alkaline earth metal salts can also be phosphates, chlorides, permanganates, and combinations thereof, or carbonates. Alkaline earth metal carbonates can be referred to as halogen-free flame retardants. Examples of alkaline earth metal carbonates include calcium carbonate, magnesium carbonate, barium carbonate, and combinations thereof. One or more embodiments specify that the alkaline earth metal carbonate is calcium carbonate.

[0031] Alkaline earth metal carbonates can have an average particle size (D50) of 1 micrometer to 15 micrometers (which can be unimodal or have a particle size distribution ranging from 0.5 micrometers to 100 micrometers). Alkaline earth metal carbonates can have a particle size of approximately 2.7 g / cm³. 3 Density (can be 2g / cm³) 3 Up to 3g / cm 3 (within the range).

[0032] Alkaline earth metal carbonates can have an average particle size (D50) ranging from 1 micrometer to 15 micrometers (ranging from 0.5 micrometers to 100 micrometers). Alkaline earth metal carbonates can have a particle size of approximately 2.7 g / cm³. 3 Density (can be 2g / cm³) 3 Up to 2g / cm 3 (within the range).

[0033] Based on 100% by weight of foam formulation, alkaline earth metal carbonates may comprise from 0.5% by weight to 20% by weight of the foam formulation. This includes all individual values ​​and sub-ranges from 0.5% by weight to 20% by weight; for example, based on 100% by weight of foam formulation, alkaline earth metal carbonates may comprise from a lower limit of 0.5% by weight, 1% by weight, 2% by weight, or 3% by weight to an upper limit of 20% by weight, 15% by weight, or 10% by weight.

[0034] The foam formulations disclosed herein may contain chain extenders. Suitable chain extenders are hydroxyl and / or amine-functionalized compounds, which also include compounds commonly referred to as crosslinking agents. Chain extenders are compounds containing two or more isocyanate reactive groups, such as hydroxyl groups, primary or secondary amines, but not limited to amines, including polyamines; polyols; polyoxyethylene polyols; polyhydroxy aromatic compounds and combinations thereof. Examples of amines include, but are not limited to, diethanolamine, triethanolamine, triisopropanolamine, diisopropanolamine, tert-butyltoluene diamine, triaminononane, diethyltoluene diamine, chlorodiaminobenzene, 4,4'-methylene-bis-(3-chloro-2,6-diethylaniline), and combinations thereof. Examples of polyols include, but are not limited to, 1,3-butanediol, 1,4-butanediol, 1,6-hexanediol, ethylene glycol, diethylene glycol, triethylene glycol, 1,2,4-butanetriol, dipropylene glycol, glycerol, trimethylolpropane, pentaerythritol, 2,5-dimethyl-1,2,6-hexanetriol, glycerol, propylene glycol, dipropylene glycol, tripropylene glycol, and combinations thereof. Examples of chain extenders include ethylenediamine, propylenediamine, diethanolamine, triethanolamine, triisopropanolamine, diisopropanolamine, tert-butyltoluenediamine, triaminononane, diethyltoluenediamine, chlorodiaminobenzene, 4,4'-methylenebis-(3-chloro-2,6-diethylaniline), and combinations thereof. Chain extenders can be prepared using known equipment, reaction conditions, and reaction components. Chain extenders are commercially available.

[0035] When used, the chain extender may be 0.1% to 5% by weight of the foam formulation, based on 100% by weight of the foam formulation. This includes all individual values ​​and sub-ranges from 0.1% to 5% by weight; for example, the chain extender may be 0.1%, 0.5%, or 1% by weight (lower limit) to 5%, 4%, or 3% by weight (upper limit) of the foam formulation, based on 100% by weight of the foam formulation.

[0036] The foam formulations disclosed herein may contain one or more catalysts. The catalyst may be a foaming catalyst, a gelling catalyst, a trimerizing catalyst, or a combination thereof. As used herein, foaming catalysts and gelling catalysts may be distinguished by the following general tendency: in the case of a foaming catalyst, there is a preference for the urea (foaming) reaction, or in the case of a gelling catalyst, there is a preference for the urethane (gelling) reaction; or in the case of a foaming / gelling catalyst, there is a tendency to generally enhance both the foaming and gelling reactions.

[0037] Examples of foaming catalysts include, but are not limited to, short-chain tertiary amines or oxygen-containing tertiary amines. Amine catalysts do not need to be sterically hindered. For example, foaming catalysts include bis-(2-dimethylaminoethyl) ether; pentamethyldiethylenetriamine, triethylamine, tributylamine, N,N-dimethylaminopropylamine, dimethylethanolamine, N,N,N',N'-tetramethylethylenediamine, and combinations thereof. Examples of commercially available foaming catalysts are POLYCAT 5 from Evonik, and other commercially available foaming catalysts.

[0038] Examples of gelling catalysts 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) dioctanoate, 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 can also be used as gelling catalysts, such as, for example, bismuth octanoate. Cyclic tertiary amines and / or long-chain amines include dimethylbenzylamine, triethylenediamine, and combinations thereof. Examples of commercially available gelling catalysts include POLYCAT 8, POLYCAT 9, POLYCAT 203, POLYCAT SA-2LE, DABCO 33 LV, DABCOBL-11, DABCO EG and DABCO T-12 from Evonik, as well as other commercially available gelling catalysts.

[0039] Examples of commercially available trimerizing catalysts include POLYCAT 41, DABCO K 2097, and DABCO TMR 30 from Evonik, as well as other commercially available trimerizing catalysts.

[0040] When used, the catalyst may be present in amounts from 0.01 wt% to 5 wt% of the foam formulation, based on 100 wt% of the foam formulation. This includes all individual values ​​and sub-ranges from 0.01 wt% to 5 wt%; for example, the catalyst may be present in amounts from a lower limit of 0.01 wt%, 0.1 wt%, 0.5 wt%, or 1 wt% to an upper limit of 5 wt%, 4 wt%, or 3 wt% based on 100 wt% of the foam formulation.

[0041] Foam formulations may contain one or more surfactants. Surfactants used in the preparation of polyurethane foams are well known to those skilled in the art, and many are commercially available. Surfactants may be silicone surfactants, non-silicone surfactants, or combinations thereof. Surfactants may be hydrocarbon-based organic surfactants. Examples of suitable silicone surfactants include, but are not limited to, TEGOSTAB B-8427, B-8454, B-8404, B-1045, B-8407, B-8409, B-84201, B-84711, B-8715 and B-8462 from Evonik; NIAX L-2171, L-5107, L-5130, L-5180, L-5340, L-5440, L-6100, L-6900, L-6980 and L-6988 from Momentive; and VORASURF DC 5164 and VORASURF SF2937 from Dow Chemical. Examples of non-silicone surfactants include, but are not limited to, ethoxylated alkylphenols, ethoxylated fatty alcohols, paraffin oil, castor oil esters, castor oil esters, Turkish red oil, peanut oil, paraffin, silicone surfactants, and fatty alcohols.

[0042] When used, the surfactant may be present in amounts from 0.01% to 5% by weight of the foam formulation, based on a 100% by weight basis. This includes all individual values ​​and sub-ranges from 0.01% to 5% by weight; for example, the surfactant may be present in amounts from a lower limit of 0.01%, 0.05%, or 0.1% by weight to an upper limit of 5%, 4%, 3%, 2%, or 1% by weight, based on a 100% by weight basis.

[0043] Foam formulations may contain one or more additives, such as additives as the isocyanate reactive side (polyol side) or isocyanate side, or both. Examples of additives include powder stabilizers, thixotropic agents such as emulsifiers, diluents, reactive diluents, antifreeze additives, poloxamer, viscosity modifiers, plasticizers, smoke suppressants, fragrances, reinforcing agents, dyes, colorants, pigments, preservatives, rheology modifiers, cell stabilizers, inhibitors, odor masking agents, internal mold release agents, biocides, antioxidants, UV stabilizers, antistatic agents, cell expanders, inorganic fillers (including pyrolytic silica, aluminum trihydrate, etc.), known flame retardant additives and molecules, etc. Different amounts of one or more other known components may be used as needed for various applications.

[0044] The foam formulation contains isocyanates. Suitable isocyanates include polyisocyanates having an average of more than 1.0 isocyanate groups per molecule. Examples of suitable isocyanates include, but are not limited to, polymethylene polyphenyl isocyanate, toluene 2,4- / 2,6-diisocyanate (TDI), methylene diphenyl diisocyanate (MDI), polymeric MDI, triisocyanate nonane (TIN), naphthyl diisocyanate (NDI), 4,4'-diisocyanate dicyclohexylmethane, 3-isocyanate methyl-3,3,5-trimethylcyclohexyl isocyanate (isophorone diisocyanate IPDI), tetramethylene diisocyanate, hexamethylene diisocyanate (HDI), 2-methyl The isocyanates include pentamethyl diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate (THDI), dodecamethyl diisocyanate, 1,4-diisocyanate-cyclohexane, 4,4'-diisocyanate-3,3'-dimethyldicyclohexylmethane, 4,4'-diisocyanate-2,2-dicyclohexylpropane, 3-isocyanate-methyl-1-methyl-1-isocyanate-cyclohexane (MCI), 1,3-diisooctylcyanate-4-methylcyclohexane, 1,3-diisocyanate-2-methylcyclohexane, and combinations thereof. Suitable isocyanates include isocyanate prepolymers, which can be prepared by reacting one or more isocyanates in stoichiometric excess with a polyol. When preparing isocyanate prepolymers, a stoichiometric ratio of at least 2:1 of isocyanate groups (NCO) to hydroxyl groups (OH) is preferred.

[0045] As mentioned, the average functionality of isocyanates can be greater than 1.0 isocyanate groups / molecule. For example, isocyanates can have an average functionality of 1.5 to 5.0. This includes all individual values ​​and sub-ranges from 1.5 to 5.0; for example, isocyanates can have an average functionality from a lower limit of 1.5, 1.7, 2.0, 2.3 or 2.5 to an upper limit of 5.0, 4.5, 4.0, 3.5 or 3.0.

[0046] Isocyanates may have isocyanate equivalents from 80 g / mol NCO to 200 g / mol NCO (e.g., g / mol NCO, i.e., NCO at the isocyanate end group) as determined according to ASTM D5155. This includes all individual values ​​and sub-ranges from 80 g / mol NCO to 200 g / mol NCO; for example, isocyanates may have isocyanate equivalents from lower limits of 80 g / mol NCO, 90 g / mol NCO, 100 g / mol NCO, 115 g / mol NCO, or 120 g / mol NCO to upper limits of 200 g / mol NCO, 175 g / mol NCO, 160 g / mol NCO, 150 g / mol NCO, or 145 g / mol NCO. The isocyanate equivalent can be converted to NCO content (%NCO) using the following expression: 42.017 g / mol NCO divided by the isocyanate equivalent multiplied by 100.

[0047] Isocyanates can be prepared by known methods. Isocyanates are commercially available. Examples of commercial isocyanates include, but are not limited to, polyisocyanates available from Dow Chemical Company under the trade names VORANATE, ISONATE, PAPI, VORACOR (such as VORACOR CL 100 or VORACOR CE 101), and PAPI, as well as other commercial isocyanates.

[0048] Isocyanates may comprise 25% to 75% by weight of the foam formulation based on 100% by weight. This includes all individual values ​​and sub-ranges from 25% to 75% by weight; for example, isocyanates may comprise a lower limit of 25%, 30%, or 35% by weight to an upper limit of 75%, 65%, or 55% by weight based on 100% by weight of the foam formulation.

[0049] Isocyanates can be used to provide an isocyanate index of 105 to 160. This includes all individual values ​​and sub-ranges from 105 to 160; for example, isocyanates can be used to provide an isocyanate index from a lower limit of 105 or 110 to an upper limit of 160, 150, 145, or 130. One or more embodiments specify that isocyanates can be used to provide an isocyanate index of 115. The isocyanate index can be determined as [moles of isocyanate groups / moles of active hydrogen groups × 100]. In this context, active hydrogen groups can include hydroxyl groups (-OH) and primary amine (-NH2) and secondary amine (>NH) groups. To calculate the isocyanate index, 1 mole of water is equivalent to 2 moles of active hydrogen groups.

[0050] The components discussed herein can be mixed together to produce foam formulations. One or more embodiments specify that the surfactant, catalyst, blowing agent, and polyol can be mixed together prior to their incorporation with the isocyanate. Foam formulations can be produced using known equipment, conditions, and components. For example, the components can be mixed together using equipment such as spray equipment, low-pressure impact mixers, high-pressure impact mixers, static mixers, impact mixers, overhead mixers with impellers or paint mixers, liquid dispensing guns or mixing heads, or static plus dynamic mixers or stirring vessels.

[0051] This process allows foam formulations to be cured to manufacture foam products. Typically, the foam formulation is subjected to conditions sufficient to allow a foaming reaction to occur in order to manufacture the foam product. Known conditions for curing foam can be utilized.

[0052] Advantageously, foam products made from the foam formulations disclosed herein can provide a UL-94 vertical flammability rating of V-0, V-1, or V-2. As mentioned, UL-94 is a known standard for flammability testing. UL-94 provides ratings including V-0 (best performance), V-1 (performance below V-0), V-2 (performance below V-1), and unqualified (performance below V-2). A UL-94 vertical flammability rating of V-0, V-1, or V-2 is desirable for many applications, including electric vehicle (EV) battery components, where the foam product may or may not have direct physical contact with lithium-ion or sodium-ion batteries.

[0053] Foam products made from the foam formulations disclosed herein can have a content of 0.30 g / cm³. 3 Up to 0.9 g / cm 3 The density. Foam products can be called high-density foam. Including 0.30 g / cm³. 3 Up to 0.9 g / cm 3 All individual values ​​and sub-ranges; for example, foam products may have a lower limit of 0.30 g / cm³. 3 0.35g / cm 3 0.40 g / cm 3 Or 0.45g / cm 3 Up to the upper limit of 0.9g / cm 3 0.75g / cm 3 0.70g / cm 3 0.65g / cm 3 Or 0.60 g / cm 3 The density can be determined according to ASTM D1622-08.

[0054] Foam products made from the foam formulations disclosed herein can provide a modulus of elasticity greater than 100 MPa. For example, foam products made from the foam formulations disclosed herein provide a modulus of elasticity from 105 MPa to 800 MPa. This includes all individual values ​​and sub-ranges from 105 MPa to 800 MPa; for example, foam products can provide a lower limit of 105 MPa, 200 MPa, or 350 MPa to an upper limit of 800 MPa, 700 MPa, or 650 MPa. The modulus of elasticity can be determined according to ASTM D1708-06 or ASTM D638-03.

[0055] Foam products made from the foam formulations disclosed herein can provide an elongation at break greater than 3%. For example, foam products made from the foam formulations disclosed herein provide an elongation at break from 3.2% to 10%. This includes all individual values ​​and sub-ranges from 3.2% to 10%; for example, foam products can provide an elongation at break from a lower limit of 3.2%, 3.5%, or 3.7% to an upper limit of 40%, 30%, 20%, 10%, 9%, or 8%. The elongation at break can be determined according to ASTM D1708-06 or ASTM D638-03.

[0056] Foam products made from the foam formulations disclosed herein can provide tensile strengths greater than 4 MPa. For example, foam products made from the foam formulations disclosed herein provide tensile strengths from 4.01 MPa to 20 MPa. This includes all individual values ​​and sub-ranges from 4.01 MPa to 20 MPa; for example, foam products can provide tensile strengths from a lower limit of 4.01 MPa, 4.05 MPa, or 4.09 MPa to an upper limit of 20 MPa, 15 MPa, or 13 MPa. Tensile strengths can be determined according to ASTM D1708-06 or ASTM D638-03.

[0057] The foam products disclosed herein provide a combination of desired properties. The foam products disclosed herein are advantageously used in many applications, such as automotive applications, etc. The compositions, foam products, multilayer compositions containing one or more foam product layers, and methods disclosed herein can be used in a variety of end applications. The foam products disclosed herein can be used in various applications, such as electric vehicle (EV) battery pack assemblies, and other applications. One or more embodiments provide EV battery pack assemblies comprising foam products made from the foam formulations disclosed herein. Methods may include preparing the foam formulation by: combining an isocyanate component and an isocyanate reactive component to form a mixture; and reacting the mixture to form a foam product. Composite articles can be prepared by: setting the disclosed composition on a substrate and curing the composition to produce a composite article comprising a foam product on the substrate. In some cases, the substrate may define at least one gap, and the setting may include placing the composition in at least one gap such that the foam product is present within the gap in the composite article. For example, the substrate may include the surface of a battery cell, metal or plastic, or component, and the composite article may include a battery pack and / or module. However, foam products can be used in other end-use applications, including as potting or encapsulating agents in end-uses other than battery packs, such as for circuits, and for purposes other than potting and / or encapsulating agents.

[0058] The compositions disclosed herein can be used as potting compounds or thermal barrier layers for electrical, battery pack, and / or module-related applications. When used as potting compounds, they can cover, encapsulate (completely or partially), and / or protect electrical connections from destructive environments such as heat, cold, flame, weather factors, dust (e.g., sand or dirt particles), physical shock or vibration, or other destructive factors. The amount of potting compound used can range from a minimum sufficient to coat and protect electrical connections to a maximum sufficient to fill voids in battery cells, junction boxes, etc., and includes that maximum amount. Similarly, when not in direct contact with the battery but in contact with the housing / enclosure of the module or assembly, they can be used as thermal or fire-resistant barriers between the battery and external heat or mechanical stress sources. The foam formulations disclosed herein can be disposed on high surface energy substrates including metals such as aluminum, steel or alloys, zinc, etc.; non-metals including glass, polar polymers and plastics such as epoxy resins, polyurethanes or polyesters, surface-activated non-polar polymers and plastics such as polypropylene, high-density or low-density polyethylene; and coating materials such as epoxy-coated aluminum, nickel-coated steel, polyacrylate-coated aluminum, polyester-lined aluminum, polyethylene terephthalate-lined steel, etc. The compositions disclosed herein can also be used in stationary energy storage applications in private and commercial environments. Compositions can be formulated to meet the constraints of automotive, mobility solutions (e.g., EVs), but can be modified beyond these constraints for other relevant electrical and stationary energy storage applications. For example, stationary energy storage applications can be formulated at higher density / weight, where considerations of total weight and lack of external cooling are not driving factors. The PU compositions disclosed herein can be applied to any of the substrates listed above using suitable methods, such as dispensing, injecting, or spraying onto one or more specific locations in and / or above a battery pack or module, to achieve complete (or partial) filling of cavities or spaces. Multilayer composites are provided such that a second self-leveling polyurethane composition, either foamed or non-foamed, can be applied on top of or below a first foam layer produced by the formulations disclosed herein. The self-leveling of the second layer can be quantified such that the difference between the highest and lowest levels of the layer is less than 25% of the highest height of the second layer. One or more embodiments provide a multilayer assembly providing a UL-94 vertical flammability rating of V-0, V-1, or V-2, wherein a layer of foam product as discussed herein is applied to an electric vehicle (EV) battery assembly, and a self-leveling layer of polyurethane product is applied on top of the layer of foam product.

[0059] Example

[0060] In the embodiments, various terms and names for materials are used, including, for example, the following:

[0061] High hydroxyl number polyether polyol (glycerol propoxylated polyol; initiator average hydroxyl functionality 3; using ASTM D4274-21, average hydroxyl number 640mg KOH / g-675mg KOH / g; average equivalent 85g / mol OH);

[0062] Low hydroxyl number polyether polyol (propoxylated diol (which is ethylene oxide, i.e., EO-terminated); initiator average hydroxyl functionality 2; using ASTM D4274-21, average hydroxyl number 27mg KOH / g-31mg KOH / g; average equivalent 1955g / molOH).

[0063] Chain extender (1,4-butanediol, obtained from Sigma-Aldrich);

[0064] Foaming agent (water);

[0065] Flame retardant 1 (ammonium polyphosphate (CAS No. 68333-79-9, phosphorus content 31%-32% by weight, crystal type II, d50 particle size 15 to 17 micrometers, decomposition temperature greater than 275℃, and density 1.9 g / cm³) 3 EXOLIT AP 422; obtained from Clariant Corporation);

[0066] Flame retardant 2 (alkaline earth metal salt; alkaline earth metal carbonate; calcium carbonate; SNOWHITE 12-PT; d50 particle size grade of 12 microns, and 2.7 g / cm³) 3 Density, obtained from Omya;

[0067] Flame retardant 3 (alkaline earth metal salt; alkaline earth metal carbonate; coated calcium carbonate; SUPERCOAT grade with d50 particle size of 1.25 microns, 1.2 wt% proprietary hydrophobic coating, and 2.7 g / cm³) 3 Density; obtained from Imerys);

[0068] Catalyst 1 (gelling catalyst, DABCO BL-11, obtained from Evonik).

[0069] Catalyst 2 (gelling catalyst, DABCO 33 LV, obtained from Evonik);

[0070] Catalyst 3 (a temperature-delayed gelation catalyst, POLYCAT SA-2LE, obtained from Evonik).

[0071] Surfactant (organosilicone polyether surfactant; VORASURF SF 2937; obtained from Dow Chemical Company);

[0072] Isocyanate (polymethylene polyphenyl isocyanate containing methylene biphenyl diisocyanate (MDI); average functionality 2.7; 32.0% NCO by weight, determined according to ASTM D5155).

[0073] The foam formulation of Example 1 was prepared as follows. All components except isocyanate were added to a container and mixed at 2,350 rpm for 5 minutes using a DAC600.1 Hauschild SpeedMixer. The mixed components were then weighed, and the required amount of isocyanate was added. The contents of the container were then mixed at 3,000 rpm for 7 seconds using high-shear impeller blades.

[0074] Examples 2-8 and Comparative Example AH were performed as in Example 1, with any changes shown in Tables 1-2.

[0075] Table 1

[0076]

[0077] Table 2

[0078]

[0079] The foam product of Example 9 was manufactured as follows. 240g of product from Example 1 was poured into a preheated (40°C) rectangular mold (20×20×10cm). 3 Then, the mold was placed in an oven (40°C) for 30 minutes. Then, Example 9 was demolded, and characteristic 1 was determined as further discussed herein. For characteristics 2-15 as further discussed herein, Example 1 (120g) was used, and a rectangular mold (20×20×5cm) was used. 3 ).

[0080] Examples 10-15 and Comparative Example IP were manufactured as in Example 9, except that Examples 2-8 and Comparative Example AH were used instead of Example 1.

[0081] The values ​​of the properties of the foam products are shown in Tables 3-6.

[0082] Table 3

[0083]

[0084] Table 4

[0085]

[0086] Table 5

[0087]

[0088] Table 6

[0089]

[0090] The data in Tables 3-6 show that, in contrast to Comparative Example IP, which provided a non-compliant UL-94 vertical flammability rating, Examples 9-16 provided a UL-94 vertical flammability rating of V-0 or V-1.

[0091] The data in Tables 3-6 show that Examples 9-16 have a concentration of 0.30 g / cm³. 3 Up to 0.9 g / cm 3 The density.

[0092] The data in Tables 3-6 show that Examples 9-16 provide an elastic modulus greater than 100 MPa.

[0093] The data in Tables 3-6 show that Examples 9-16 provide an elongation at break greater than 3%.

[0094] The data in Tables 3-6 show that Examples 9-16 provide tensile strengths greater than 4 MPa.

[0095] Characteristic 1 corresponds to the UL 94 test, which is the standard for testing the flammability of plastic materials. To determine Characteristic 1, the corresponding foam samples are cut into 0.5-inch wide and ≥10 cm dimensions. These samples are then tested according to the UL-94 vertical burning protocol. The performance is classified into the appropriate category: V-0 (best performance), V-1 (performance below V-0), V-2 (performance below V-1), and unqualified (unqualified indicates that the potting compound sample burns to the fixture during and / or after flame exposure).

[0096] Characteristic 2 corresponds to resistivity. Resistivity was determined using a Keithley 6517B electrometer with a Keithley 8009 test cell, according to ASTM D257. Each sample was measured five times in this manner to calculate the average and error bars.

[0097] Properties 3 and 4 correspond to dielectric strength and dielectric constant, respectively. Dielectric strength was determined using a Hipotronics 750-2 / D149 dielectric strength tester according to ASTM D149. The dielectric strength is reported as the breakdown voltage divided by the sample thickness. The dielectric constant was determined using a Novocontrol broadband dielectric spectrometer according to ASTM D150.

[0098] Characteristic 5 corresponds to thermal conductivity. Thermal conductivity was determined according to ISO 22007-2 using a TPS 2500S Hot Disk apparatus with a Kapton Insulated 5465 F1 sensor on a 5 mm thick pre-cured foam sample with an isotropic (standard) module, under 50 mW heating power and a 5-second measurement time, and with standard analysis. Each sample was measured five times in this manner to calculate the average value and error bars.

[0099] Characteristic 6 corresponds to the glass transition temperature.

[0100] Properties 7-10 correspond to Dynamic Mechanical Analysis (DMA). According to ASTM D5279-21, the glass transition temperature (Property 6) and storage modulus in torsion mode at -25°C, 25°C, 50°C, and 75°C (Properties 7 through 10, respectively) were obtained via DMA using an Advanced Rheological Extension System (ARES-G2) from TA Instruments equipped with liquid nitrogen environmental control and a torsion rectangular fixture. Rectangular samples were cut from foam (described above, at a thickness of 5 mm) to dimensions of 45 mm in length and 12.8 mm in width. The sample length was aligned with the torsion axis, and DMA was performed in torsion mode. The temperature was increased from -50°C to 150°C at a heating rate of 3°C / min. The test frequency was 1 Hz at 0.05% torsional strain, with an axial tension of 0.098 N applied to keep the sample taut, and data was collected at 30-second intervals. The main outputs of the characterization are the storage modulus in terms of shear modulus (G') over the test temperature range (characteristics 7 to 10), and the Tanδ value over the test temperature, the peak of which is specified as the glass transition temperature (Tg in °C) (characteristic 6).

[0101] Characteristic 11 corresponds to elongation at break.

[0102] Property 12 corresponds to ultimate tensile strength, also known as tensile strength.

[0103] Characteristic 13 corresponds to the elastic modulus.

[0104] According to ASTM D1708-06, elongation at break (%), ultimate tensile strength (MPa), and modulus of elasticity (MPa) were determined using foam (as described above, at a thickness of 5 mm) on an MTS machine. Micro-stretched samples were stamped into a micro-stretched dog-bone shape and conditioned for at least 24 hours prior to testing at 50% relative humidity (+ / -10%) and 75℉ temperature (+ / -5℉).

[0105] Characteristic 14 corresponds to g / cm 3Density is expressed in units of ASTM D1622-08.

[0106] Characteristic 15 corresponds to hardness. The hardness is determined using a Shore D hardness tester according to ASTM D2240 approximately 2 minutes after foam demolding.

Claims

1. A rigid foam formulation, said rigid foam formulation comprising: High hydroxyl number polyether polyol, wherein the high hydroxyl number polyether polyol has an average hydroxyl number of 350 mg KOH / g to 1,900 mg KOH / g and an average hydroxyl functionality of 1.5 to 8; Low hydroxyl number polyether polyol, wherein the low hydroxyl number polyether polyol has an average hydroxyl number of 7 mg KOH / g to 70 mg KOH / g and an average hydroxyl functionality of 1.5 to 8; Ammonium polyphosphate; Alkaline earth metal salts; foaming agent; and Isocyanates.

2. The rigid foam formulation according to claim 1, wherein: Based on 100% by weight of the foam formulation, the high hydroxyl polyether polyol accounts for 10% to 30% by weight of the foam formulation. Based on 100% by weight of the foam formulation, the low hydroxyl number polyether polyol accounts for 10% to 30% by weight of the foam formulation. Based on 100% by weight of the foam formulation, the ammonium polyphosphate accounts for 0.5% to 30% by weight of the foam formulation; Based on 100% by weight of the foam formulation, the foaming agent accounts for 0.01% to 10.5% by weight of the foam formulation; Based on 100% by weight of the foam formulation, the alkaline earth metal salt accounts for 0.5% to 20% by weight of the foam formulation; and Based on 100% by weight of the foam formulation, the isocyanate accounts for 25% to 75% by weight of the foam formulation.

3. The rigid foam formulation according to any one of claims 1 to 2, wherein the rigid foam formulation further comprises: Chain extender; Catalyst; and Surfactants.

4. The rigid foam formulation according to claim 3, wherein: Based on 100% by weight of the foam formulation, the chain extender accounts for 0.1% to 5% by weight of the foam formulation; Based on 100% by weight of the foam formulation, the catalyst accounts for 0.01% to 5% by weight of the foam formulation; and Based on 100% by weight of the foam formulation, the surfactant accounts for 0.01% to 5% by weight of the foam formulation.

5. The rigid foam formulation according to any one of claims 1 to 4, wherein the alkaline earth metal salt is calcium carbonate, magnesium carbonate, barium carbonate, or a combination thereof.

6. The rigid foam formulation according to any one of claims 1 to 5, wherein the foaming agent is water.

7. The rigid foam formulation according to any one of claims 1 to 6, wherein the high hydroxyl number polyether polyol is a glycerol alkoxylated polyether polyol, and the low hydroxyl number polyether polyol is a bifunctional polyether polyol.

8. A foam product formed by curing a rigid foam formulation according to any one of claims 1 to 7, wherein the foam product has a content of 0.3 g / cm³ as determined according to ASTM D1622-08. 3 Up to 0.9 g / cm 3 The density.

9. The foam product of claim 8, wherein the foam product provides a UL-94 vertical flammability rating of V-0, V-1 or V-2.

10. A multilayer assembly providing a UL-94 vertical flammability rating of V-0, V-1, or V-2, wherein a layer of foam product according to any one of claims 8 to 9 is applied to an electric vehicle (EV) battery assembly, and a self-leveling layer of polyurethane product is applied on top of the layer of foam product.

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