Polyurea particle dispersions for polyurethane foam applications

Abstract

The present disclosure provides a method of forming a dispersion of polyurea particles in a polyol. The method can include providing a polyol dispersion formulation comprising: a base polyol; a polyisocyanate; and an amine mixture, wherein the amine mixture comprises a first aliphatic amine having an amine functionality of 1; a second aliphatic amine having an amine functionality of 2 to 5; and an aromatic amine having an amine functionality of 1 to 4; and reacting the polyisocyanate and the amine mixture in the base polyol to form a dispersion of polyurea particles in a polyol.

Description

Technical Field

[0001] This disclosure relates in its entirety to polyol dispersions for use in flexible polyurethane foam applications. Background Technology

[0002] Flexible polyurethane foams can contain fillers to help increase the foam's density and load-bearing properties. In the past, inorganic fillers such as barium sulfate have been used to achieve these properties, but the use of inorganic fillers has several drawbacks, including difficulties in preparing and maintaining the dispersion. Instead, polymer-filled polyols, also known as polyol dispersions, have been used to improve the load-bearing properties of flexible polyurethane foams or to adjust their processability. A polyol dispersion is a polyol in which solid particles are dispersed in a stable suspension. Examples of such polyol dispersions include polyurethane particle dispersions in polyols (PIPA polyols) or styrene-acrylonitrile particle dispersions in polyols (polymer polyols).

[0003] Other examples of polyol dispersions include those formed by the addition polymerization of polyisocyanates, polyamines, and polyether polyols; these are known as polyurea dispersions (PHD) polyols. Because the reaction between isocyanates and amines is so rapid that the formation of PHD polyols can be very fast, good mixing is necessary at the point of reaction to ensure a stable dispersion.

[0004] However, a drawback of PHD polyols is that they are typically manufactured using hydrazine, a harmful compound. Another disadvantage of the polyol dispersions described above is the temporal instability of the polyol particles within the dispersion. The dispersed polymer phase exhibits a strong tendency to separate from the liquid phase. Therefore, there is a need in the art to help stabilize polyol dispersions, especially PHD polyols. Summary of the Invention

[0005] This disclosure provides a method for forming polyurea particle dispersions in polyols, which helps stabilize polyol dispersions, particularly PHD polyols. The synthesis of stable polyol dispersions, including PHD polyols, is achieved by using an epoxyalkane-based polyether polyol as a base polyol, combined with a specific amine mixture for the synthesis of polyurea particle dispersions via a reaction of isocyanate and amine in the base polyol. Specifically, embodiments of this disclosure include polyol dispersion formulations comprising an amine mixture that allows for the stabilization of the polyol dispersion. In particular, it has been surprisingly found that stable polyurea dispersions are obtained when three specific amines, as discussed herein, are used together in the dispersion.

[0006] As discussed herein, this disclosure provides a method for forming a polyurea particle dispersion in a polyol. The method of this disclosure includes providing a polyol dispersion formulation comprising: a base polyol; a polyisocyanate; and an amine mixture. For various embodiments, the amine mixture comprises: 0.5 to 10 wt% of a first aliphatic amine having an amine functionality of 1; 0.5 to 15 wt% of a second aliphatic amine having an amine functionality of 2 to 5; and 0.3 to 7 wt% of an aromatic amine having an amine functionality of 1 to 4, wherein the wt% is based on the total weight of the polyol dispersion formulation; and reacting the polyisocyanate and the amine mixture in the base polyol at an NH / NCO equivalent ratio of 0.5 to 1.3 to form a polyurea particle dispersion in the polyol having a total solids content of 5 to 40 wt% based on the total weight of the polyurea particles in the polyol.

[0007] Regarding polyols, for various embodiments, the base polyol may be a polyether polyol. Specifically, for various embodiments, the polyether polyol may be selected from the group consisting of: (a) a polyether polyol formed from 100% by weight propylene oxide (PO); (b) a polyether polyol formed from PO and having ends capped with ethylene oxide (EO); and (c) a polyether polyol formed from a mixture of PO and EO (e.g., a random copolymer). For various embodiments, the polyether polyol may have an equivalent content from 200 g / equivalent to 3000 g / equivalent.

[0008] Regarding amines, for various embodiments, the weight-average molecular weight of the first aliphatic amine and the molecular weight of the second aliphatic amine can each independently range from 59 g / mol to 4000 g / mol. For various embodiments, the weight-average molecular weight of the aromatic amine can range from 90 g / mol to 1000 g / mol. Preferably, the weight-average molecular weight of the aromatic amine can range from 95 g / mol to 500 g / mol. Furthermore, for various embodiments, the first aliphatic amine and the second aliphatic amine can each contain at least one group selected from the group consisting of a hydroxyl moiety, a phosphorus moiety, and combinations thereof. In one embodiment, the amine mixture consists of a first aliphatic amine, a second aliphatic amine, and an aromatic amine. In other words, in this one embodiment, the amine mixture contains only the first aliphatic amine, the second aliphatic amine, and an aromatic amine as provided herein.

[0009] Regarding isocyanates, for various embodiments, the polyisocyanate may be selected from the group consisting of toluene diisocyanate, diphenylmethane diisocyanate, and combinations thereof. For various embodiments, the polyisocyanate and amine mixture is reacted in a base polyol at an NH / NCO equivalent ratio of 0.5 to 1.3 to form a polyurea particle dispersion in the polyol. In another embodiment, the polyisocyanate and amine mixture is reacted in a base polyol at an NH / NCO equivalent ratio of 0.75 to 1.3 to form a polyurea particle dispersion in the polyol.

[0010] In addition to the above discussion, no catalyst is required for any of the various embodiments. Therefore, no catalyst is used in the formation of the polyurea particle dispersion in the polyol for any of the various embodiments. Similarly, hydrazine is not used in the formation of the polyurea particle dispersion in the polyol for any of the various embodiments. In other words, hydrazine is never used in the formation of the polyurea particle dispersion in the polyol according to this disclosure.

[0011] This disclosure also provides a polyol dispersion formed by the method described herein. For various embodiments, at least 90% by weight of the polyurea particles in the polyol have a diameter of 18 μm or less.

[0012] This disclosure also provides a polyurethane foam comprising the reaction product of a reaction mixture, wherein the reaction mixture comprises a polyol dispersion, a blowing agent, and at least one polyisocyanate as provided herein.

[0013] Other key features and advantages of this disclosure will become apparent to those skilled in the art after reviewing the following drawings, detailed descriptions and appended claims. Detailed Implementation

[0014] This disclosure provides a method for forming polyurea particle dispersions in polyols, which helps stabilize polyol dispersions, particularly PHD polyols. The synthesis of stable polyol dispersions, including PHD polyols, is achieved by using an epoxyalkane-based polyether polyol as a base polyol, combined with a specific amine mixture for the synthesis of polyurea particle dispersions via a reaction of isocyanate and amine in the base polyol. Specifically, embodiments of this disclosure include polyol dispersion formulations comprising an amine mixture that allows for the stabilization of the polyol dispersion. In particular, it has been surprisingly found that stable polyurea dispersions are obtained when three specific amines, as discussed herein, are used together in the dispersion.

[0015] This disclosure provides polyols (polyurea particle dispersions in which polyurea particles are also referred to as PHD (polyurea dispersion) polyols). PHD polyols are conventionally prepared by reacting low equivalence (EW) isocyanate reactive molecules with polyisocyanates in the presence of a high EW polyol (also referred to as a "base polyol"). The resulting dispersed polymer phase consists of a polyurea polymer, wherein typically toluene diisocyanate (TDI) is the isocyanate and hydrazine is used as a low molecular weight polyamine. Compared to prior art, this disclosure enables the production of polyurea particle dispersions in polyols without the need for harmful polyamines such as hydrazine. As discussed herein, this disclosure provides a method for forming polyurea particle dispersions in polyols (e.g., a process for manufacturing PHD polyols) that can produce stable dispersions of polyurea particles using different types of base polyols (e.g., ethylene oxide (EO)-terminated propylene oxide (PO), EO / PO mixed feeds, or all-PO-based polyols).

[0016] As discussed herein, this disclosure provides a method for forming a polyurea particle dispersion in a polyol. The method of this disclosure includes providing a polyol dispersion formulation comprising: a base polyol; a polyisocyanate; and an amine mixture. As discussed herein, the benefit of this disclosure is that it provides the possibility of producing polyurea dispersions using multiple base polyols via a reaction of a specific combination of polyisocyanate and amine, without the use of certain harmful amines (such as hydrazine), the reaction achieving a stable polyol dispersion (e.g., PHD polyol). The polyurea particle (e.g., PHD particle) dispersion in a polyol according to this disclosure can be formed in situ in a base polyol, as provided herein, wherein the polyurea particle dispersion in the polyol has a total solids content of 5% to 40% by weight based on the total weight of the polyurea particles in the polyol. Such a high solids content can be obtained while maintaining small particle sizes. For example, in one embodiment, at least 90% by weight of the polyurea particles in the base polyol have a diameter of 18 μm or less. The in-situ formation of polyurea particles in the basic polyols according to this disclosure can be achieved without the addition of any hydrazine. Basic polyols

[0017] For various embodiments, the base polyols of this disclosure may include a variety of polyols. The base polyols of this disclosure may include the base polyols described herein as well as other base polyols known in the art, including commercially available polyols. Examples of such base polyols include polyether polyols, polyester polyols, hydroxyl-terminated acetals, hydroxyl-terminated amines, polyalkylene carbonate polyols, polyphosphate polyols, and mixtures thereof.

[0018] Preferably, the base polyol is a polyether polyol. For various embodiments, the polyether polyol can be prepared by adding an epoxide, such as ethylene oxide (EO), propylene oxide (PO), butane oxide, or combinations thereof, to an initiator having 2 to 8, preferably 2 to 6, active hydrogen atoms. The catalyst used for the polymerization of the polyether polyol can be an anionic or cationic catalyst, examples of which include KOH, CsOH, boron trifluoride, and dual-metallic cyanide complex (DMC) catalysts, such as zinc hexacyanocobaltate or quaternary phosphoric acid compounds.

[0019] Examples of suitable initiator molecules include initiator molecules with active hydrogen, such as water, polyols (especially diols to octaols) or dialkylene glycols.

[0020] Additional initiator molecules may also include, for example, ethylene glycol, 1,2-propanediol and 1,3-propanediol, diethylene glycol, dipropylene glycol, 1,4-butanediol, 1,6-hexanediol, glycerol, pentaerythritol, sorbitol, sucrose, neopentyl glycol; 1,2-propanediol; trimethylolpropaneglycerol; 1,6-hexanediol; 2,5-hexanediol; 1,4-butanediol; 1,4-cyclohexanediol; ethylene glycol; diethylene glycol; triethylene glycol; 9(1)-hydroxymethyloctadecyl alcohol; 1,4-dimethylolcyclohexane; 8,8-bis(hydroxymethyl)tricyclo[5,2,1,0] 2,6 ] Decene; dimerized glycol (36-carbon glycol, purchased from Henkel Corporation); hydrogenated bisphenol; 9,9(10,10)-dihydroxymethyl octadecyl alcohol; castor oil; epoxidized seed oil; other modified seed oils containing reactive hydrogen; 1,2,6-hexanetriol; and combinations thereof.

[0021] For various embodiments, the polyether polyol may be selected from the group consisting of: (a) a polyether polyol formed from 100% by weight propylene oxide (PO); (b) a polyether polyol formed from PO and having ends formed from ethylene oxide (EO); and (c) a polyether polyol formed from a mixture of PO and EO (e.g., a random copolymer formed from EO and PO). For example, the base polyol used to prepare the dispersion may be, for example, a poly(propylene oxide) homopolymer (e.g., a polyether polyol formed from 100% by weight PO). In another embodiment, the polyether polyol may be a poly(propylene oxide)-based polyether polyol having ends formed from EO. The polyether polyol may also be formed from PO and EO as a random copolymer, wherein the poly(ethylene oxide) content is, for example, from about 1% to about 95% by weight. In addition to ethylene oxide-terminated poly(propylene oxide) polymers, additional examples may include ethylene oxide-terminated random copolymers of propylene oxide and ethylene oxide.

[0022] For various embodiments, the polyether polyols of this disclosure may have an equivalent weight of 200 g / equivalent to 3000 g / equivalent per hydroxyl group. Preferably, the polyether polyols of this disclosure may have an equivalent weight of 200 g / equivalent to 1500 g / equivalent per hydroxyl group.

[0023] For various implementation schemes, the base polyol is not inoculated with suspended particles to facilitate the formation of polyurea particles through the reaction between the amine mixture and the polyisocyanate as provided herein. Polyisocyanates

[0024] For various embodiments, suitable polyisocyanates include aromatic polyisocyanates known in the art. Examples of such polyisocyanates include 4,4'-isomers, 2,4'-isomers, and 2,2'-isomers of diphenylmethane diisocyanate (MDI), mixtures thereof, and mixtures of polymeric MDI and monomeric MDI; toluene-2,4-diisocyanate and 2,6-diisocyanate (TDI) and mixtures thereof; m-phenyl diisocyanate and p-phenyl diisocyanate, chlorophenyl-2,4-diisocyanate, diphenyl-4,4'-diisocyanate, 4,4'-diisocyanate-3,3'-dimethyldiphenyl, 3-methyldiphenylmethane-4,4'-diisocyanate and diphenyl ether diisocyanate, and 2,4,6-triisocyanatotoluene and 2,4,4'-triisocyanatodiphenyl ether. Preferably, for various embodiments, the polyisocyanate may be selected from the group consisting of toluene diisocyanate, diphenylmethane diisocyanate, and combinations thereof. Examples of toluene diisocyanate (TDI) and diphenylmethane diisocyanate (MDI) are provided herein. Mixtures of the above-described polyisocyanates may also be used according to the invention. For example, mixtures of MDI and TDI polyisocyanates described above may be used, such as mixtures of 2,4-isomers and 2,6-isomers of TDI and / or mixtures of 4,4'-isomers, 2,4'-isomers, and 2,2'-isomers of MDI. So-called prepolymers may also be used as polyisocyanates, i.e., low molecular weight and / or high molecular weight compounds having hydroxyl groups, for example, reaction products of the compounds discussed herein reacting with an excess of the polyisocyanates described above.

[0025] Polyisocyanates as described herein may have a functionality of at least 2. For example, polyisocyanates of MDI may have a functionality of 2 to 3.2, while polyisocyanates of TDI may have a functionality of 2 to 3.0. Such polyisocyanates may include any of the polyisocyanates described above, such as pure MDI, pure TDI, and modified forms, which may include biuret-modified polyisocyanates and carbodiimide-modified polyisocyanates. Amine mixture

[0026] For various embodiments, the use of specific combinations of amines as provided herein has allowed for the stabilization of polyol dispersions, particularly PHD polyols as discussed herein. Specifically, it has been surprisingly found that stable polyurea dispersions are obtained when three specific amines are used together in the dispersion. The specific combinations of amines disclosed herein include specific aliphatic and aromatic amines. For various embodiments, the amine mixture comprises: 0.5 to 10 wt% of a first aliphatic amine having an amine functionality of 1; 0.5 to 15 wt% of a second aliphatic amine having an amine functionality of 2 to 5; and 0.3 to 7 wt% of an aromatic amine having an amine functionality of 1 to 4, wherein the wt% is based on the total weight of the polyol dispersion formulation. For various embodiments, the amine mixture consists of a first aliphatic amine, a second aliphatic amine, and an aromatic amine. In other words, in some embodiments, the amine mixture comprises only a first aliphatic amine, a second aliphatic amine, and an aromatic amine.

[0027] For various embodiments, the first aliphatic amine has an amine functionality of 1 (e.g., an NCO-reactive amine with a functionality of 1). For various embodiments, the first aliphatic amine may include those aliphatic amines having aliphatic primary or secondary amine functions. For various embodiments, the equivalent of the first aliphatic amine can be in the range of 59 g / equivalent to 4000 g / equivalent. Preferably, the equivalent of the first aliphatic amine can be in the range of 59 g / equivalent to 2000 g / equivalent. More preferably, the equivalent of the first aliphatic amine can be in the range of 100 g / equivalent to 600 g / equivalent.

[0028] For various embodiments, the first aliphatic amine may be selected from the group consisting of: alkylamines; alicyclic amines, aralkylamines; amine-terminated polyethers, substituted anilines, alkylethanolamines, and combinations thereof. Specific examples of the first aliphatic amine include, but are not limited to, propylamine, butylamine, ethanolamine, diethanolamine, polyetheramines, octylamine, dodecylamine, stearylamine, dimethylaniline, cyclohexylamine, and dicyclohexylamine. Commercial examples of the first aliphatic amine may include, but are not limited to, JEFFAMINE. ™ M-series monoamines (e.g., M-600 and M-1000, Huntsman, etc.)

[0029] For various embodiments, the second aliphatic amine has an amine functionality of 2 to 5 (e.g., an NCO-reactive amine with a functionality of 2 to 5). Preferably, the second aliphatic amine has an amine functionality of 2 to 3 (e.g., an NCO-reactive amine with a functionality of 2 to 3). For various embodiments, the second aliphatic amine may include those aliphatic amines having aliphatic primary amines, aliphatic secondary amines, or combinations thereof.

[0030] For various embodiments, the second aliphatic amine may be selected from the group consisting of: ethylenediamine (EDA), 1,2-propanediamine and 1,3-propanediamine; 1,6-hexamethylenediamine (HMDA), diethylenetriamine (DETA), piperazine, N,N'-bis-aminoethylpiperazine; triazine; higher homologues of ethylenediamine, such as diethylenetriamine; triethylenetetramine and tetraethylenepentamine; homologues of propylenediamine, such as dipropylenetriamine, 1,4-diaminocyclohexane, tris(2-aminoethyl)amine, tetramethylenediamine, hexamethylenediamine, 4,7,10-trioxatridecane-1,13-diamine and combinations thereof. Commercially available examples of second aliphatic amines may include Dytek A (Invista); Amicure IC (Albemarle); Dytek EP (Invista); Amicure CG-1200 (Albemarle); polyamine D-230 (Huntsman); ethylenediamine (BASF); polyamine AP (Huntsman); anhydrous piperazine (Huntsman); anhydrous piperazine (BASF); JEFFAMINE ™ T-403 (Huntsman); JEFFAMINE ™ D-230 (Huntsman); JEFFAMINE ™ D-400 (Huntsman); JEFFAMINE ™ D-2000 (Huntsman); JEFFAMINE ™ ED-600 (Huntsman); and JEFFAMINE ™ ED-900 (Huntsman).

[0031] For various embodiments, the aromatic amine has an amine functionality of 2 to 4 (e.g., an NCO-reactive amine with a functionality of 2 to 4). Preferably, the aromatic amine has an amine functionality of 2 (e.g., an NCO-reactive amine with a functionality of 2). For various embodiments, the aromatic amine may include those aromatic amines having primary aromatic amines, secondary aromatic amines, or combinations thereof.

[0032] For various implementations, the aromatic amines may be selected from the group consisting of: diethyltoluenediamine, 1H-pyrrole-2,5-diamine, phenylenediamine, 4,4'-methylenediphenylamine, 4,4'-methylenebis(3-chloro-2,6-diethylaniline) (MCDEA), phenylenediamine; naphthylenediamine, benzylamine, N,N,N',N'-tetramethyl-1,8-naphthylenediamine, 4-aminobenzylamine; 4-aminophenylethylamine; toluenediamine; diaminomethylbenzene, and combinations thereof. Commercial examples of such aromatic amines may include Ethacure300 (Albemarle), Ethacure 100 (Albemarle), etc.

[0033] For various embodiments, the weight-average molecular weight of the first aliphatic amine and the molecular weight of the second aliphatic amine can independently be in the range of 59 g / mol to 4000 g / mol. Preferably, the weight-average molecular weight of the first aliphatic amine and the molecular weight of the second aliphatic amine can independently be in the range of 59 g / mol to 2000 g / mol. For various embodiments, the weight-average molecular weight of the aromatic amine can be in the range of 95 g / mol to 1000 g / mol. Preferably, the weight-average molecular weight of the aromatic amine can be in the range of 95 g / mol to 500 g / mol.

[0034] For various embodiments, the first and second aliphatic amines may or may not carry additional functional groups other than the amine that react with the isocyanate. Examples of such additional functional groups may include functional groups selected from the group consisting of hydroxyl moieties, phosphorus moieties, and combinations thereof.

[0035] As discussed herein, hydrazine is not used in the amine mixtures provided herein, nor in any other aspect of the method for forming polyurea particle dispersions in polyols according to this disclosure.

[0036] For various embodiments, the use of a catalyst is optional in forming the polyurea particle dispersion in the polyol according to this disclosure. In other words, in one embodiment, no catalyst is used in forming the polyurea particle dispersion in the polyol according to this disclosure. However, if present, examples of such catalysts may include known organometallic compounds, metal salt catalysts, and tertiary amine catalysts used with the polyol in forming the polyurea particles. When present, the catalyst is used to accelerate the reaction of the isocyanate reactive groups in the isocyanate-amine mixture. Formation of polyurea particle dispersion

[0037] As discussed herein, a method for forming a polyurea particle dispersion in a polyol includes providing a polyol dispersion formulation comprising a base polyol, a polyisocyanate, and an amine mixture. The method further includes reacting the polyisocyanate and amine mixture in a base polyol at an NH / NCO equivalent ratio of 0.5 to 1.3 to form a polyurea particle dispersion in the polyol having a total solids content of 5% to 40% by weight based on the total weight of the polyurea particles in the polyol. In another embodiment, the polyisocyanate and amine mixture may be reacted in a base polyol at an NH / NCO equivalent ratio of 0.75 to 1.3 to form a polyurea particle dispersion in the polyol. This document includes and discloses all individual values ​​and sub-ranges between 5% by weight and 40% by weight of total solids content; for example, based on the total weight of polyurea particles in the polyol, the solids content can range from a lower limit of 5% by weight, 8% by weight, 10% by weight, 15% by weight, 20% by weight, 25% by weight, or 30% by weight to an upper limit of 20% by weight, 25% by weight, 30% by weight, 35% by weight, or 40% by weight. Additional fillers, such as mineral fillers, flame retardants such as melamine, or recycled foam powder may be incorporated into the polyol dispersion formulation at levels between 1% by weight and 50% by weight, or between 2% by weight and 10% by weight.

[0038] The reaction of the polyisocyanate with the amine mixture in a base polyol can occur under mixed conditions at a predetermined temperature and pressure. For example, as is known in the art, the polyisocyanate can be added to the amine mixture and the base polyol in a stirred reactor or by using a series of static mixers, or more preferably, by continuous addition using a high-pressure mixing head, such as those used in polyurethane foaming machines, wherein the base polyol, polyisocyanate, and amine mixture have multiple streams. For various embodiments, the predetermined temperature can be in the range of about 20°C to 120°C, wherein the predetermined temperature is preferably in the range of about 20°C to 60°C. For various embodiments, the predetermined pressure can be in the range of about 101.3 kPa to 690 kPa.

[0039] For various embodiments, the polyol dispersion is formed by the method described herein. For various embodiments, for the polyol dispersion, at least 90% by weight of the polyurea particles in the polyol have a diameter of 18 μm or less.

[0040] As discussed herein, hydrazine is not used in forming the polyurea particle dispersion in the polyol. In another embodiment, the catalyst discussed herein is not used in forming the polyurea particle dispersion in the polyol.

[0041] This disclosure also provides a polyurethane foam comprising the reaction product of a reaction mixture, wherein the reaction mixture comprises a polyol dispersion as provided herein, a blowing agent, and at least one polyisocyanate. For various embodiments, the polyol dispersion as provided herein, together with at least one polyisocyanate, can be used in conventional block foam, highly flexible flexural foam, or viscoelastic foam applications, as well as other polyurethane foam configurations.

[0042] Generally, the polyurethane foam of this disclosure can be prepared by mixing a polyisocyanate (such as the polyisocyanates listed above or combinations thereof) with a polyol dispersion of this disclosure in the presence of a blowing agent, optional catalyst, and other desired optional components. Additional polyols and / or polymeric polyols may be added to the polyol dispersion prior to reaction with the polyisocyanate. The reaction conditions allow the polyisocyanate and polyol dispersion to react to form a polyurethane and / or polyurea polymer, while the blowing agent generates a gas that expands the reaction mixture.

[0043] Any suitable polyurethane catalyst can be used, including tertiary amine compounds, amines having isocyanate reactive groups, and organometallic compounds. Exemplary tertiary amine compounds include triethylenediamine, N-methylmorpholine, N,N-dimethylcyclohexylamine, pentamethyldiethylenetriamine, tetramethylethylenediamine, bis(dimethylaminoethyl) ether, 1-methyl-4-dimethylaminoethyl-piperazine, 3-methoxy-N-dimethyldimethylpropylamine, N-ethylmorpholine, dimethylethanolamine, N-cocomorpholine, N,N-dimethyl-N',N'-dimethylisopropylpropylenediamine, N,N-diethyl-3-diethylaminopropylamine, and dimethylbenzylamine. Exemplary organometallic catalysts include organomercury catalysts, organolead catalysts, organoiron catalysts, organobismuth catalysts, and organotin catalysts, wherein no organometallic catalyst is preferred. Catalysts for the trimerization of isocyanates to produce isocyanurates, such as alkali metal alkoxides, may also be optionally employed herein. The amount of amine catalyst in the formulation can vary from 0.02% to 5%, or an organometallic catalyst can be used from 0.001% to 1% in the formulation.

[0044] Examples of blowing agents include physical blowing agents such as carbon dioxide, air, nitrogen, dichloromethane, hydrofluorocarbons (HFCs) (such as HFC-134a, HFC-245fa), hydrocarbons (such as n-pentane, isopentane, cyclopentane); and chemical blowing agents such as water and formic acid. The amount of blowing agent used can be from 1 to 30 parts by weight of the polyol dispersion of this disclosure.

[0045] In addition, it may be desirable to use certain other components in the preparation of polyurethane foam. These additional components include emulsifiers, siloxane surfactants, preservatives, flame retardants, colorants, antioxidants, reinforcing agents, UV stabilizers, and other known additives. Example

[0046] Unless otherwise specified, all components were purchased from commercial suppliers and used as is. Unless otherwise specified, the amounts provided for the Examples (EX) and Comparative Examples (CE), as well as the components used in forming EX and CE, are all expressed as weight percentages (wt%). The components used in forming EX and CE are provided in Table 1. Table 1

[0047] Methods and procedures

[0048] The following are the methods and procedures for the embodiments.

[0049] The process for preparing the PHD polyol dispersion involves mixing the base polyol and amine until homogeneous. Isocyanate (0.1 g / s) is then slowly added while stirring. Once added, the mixture is stirred for another 2 minutes to complete the synthesis of the PHD polyol dispersion.

[0050] The process for preparing polyurethane foam. Foam is prepared according to a manual mixing procedure. After manual mixing for 12 seconds, the foam is molded in an 11-liter (L) Al flat mold at 45°C. The polyol is weighed and mixed with surfactant, water, and an amino catalyst (Niax). ® A1 and Dabco ® Mix 33 LV together. Set the mixer speed to 2000 rpm; start mixing; add Dabco. ® T9; Adding Dabco ® Ten seconds after T9, add isocyanate; ten seconds after adding isocyanate, pour the reaction mixture into an open box. After a 5-minute demolding time, mechanically crush the foam between two metal rollers with a 4-cm gap between the rollers through which the foam passes. Test methods

[0051] Particle size distribution (PSD) (d90): In PSD, d90 corresponds to the point in the particle size distribution where 90% of the total volume of material in the sample is "included" (up to and including that point). For example, if D90 is 10 μm, it means that 90% of the sample has a size of 10 μm or smaller.

[0052] Procedure: Disperse 0.5 g of polyurea dispersion in 50 mL of IPA (isopropanol). Use a Malvern Panalytical Mastersizer 3000 to test the solution and measure PSD. Distribution is reported as dQ3 / dx, which is the cumulative volume distribution (Q3) as a function of particle size (x).

[0053] The molecular weight (MW) of a polyol is defined as the equivalent weight (EW) multiplied by its functionality. EW is obtained by dividing 56100 by the OH value of the polyol. The OH value (hydroxyl value) of a polyol is determined according to ASTM D4274.

[0054] Flammability test: UNI 9175 Class 1 IM. Tested according to Italian flammability standard UNI 9175 Class 1 IM for foam (450×300×75mm). 3 For testing, two pieces of foam are placed on a specific metal support to create a seat and backrest. A propane flame with a height of 40 mm is placed at the junction of the seat and backrest. For Class 1 IM, an ignition time of 140 seconds (s) is used, followed by 120 seconds of self-extinguishing time for the foam. The foam is tested as a seat surface, ignited 3 to 5 times, each time in a brand new area. Fire results are reported as a pass rate, where 100% pass means that all ignitions on the seat surface pass the standard.

[0055] Density: determined according to ISO D 845.

[0056] Compression set and elongation at break: determined according to ASTM D 3574.

[0057] Compressive stress / strain characteristics (CLD) at 40%: determined according to ISO 3386-1 result

[0058] Referring to Table 2, Comparative Examples CE-A, CE-B, and CE-C describe examples in which one of the three amines (aliphatic monoamine, aliphatic polyamine, or aromatic diamine) is missing, which results in an excessively high particle size distribution PSD (d90), thus making the resulting polyurea dispersion unstable.

[0059] The percentage of solids is a calculated value, which refers to the amount of amine plus isocyanate used in the preparation of polyol dispersions.

[0060] The viscosity of CE-B (aromatic terminal-capped polyol) is 11,000 mPa. . The viscosity of EX-1 to EX-5 is approximately 2500 mPa. . Viscosity was measured according to ASTM D4289.

[0061] EX-1 to EX-5 describe embodiments of the invention in which three types of amines are used while maintaining an NH / NCO ratio in the range of 0.91 to 0.97. All examples show the formation of particles with low PSD (d90). EX-6 and EX-7 both show embodiments of the invention with NH / NCO (equivalent ratio of amine to isocyanate) ranges of 1.21 and 0.85, respectively. Both examples produce particles with low PSD (d90), which supports the claim that polyurea dispersions can be efficiently produced when operating at NH / NCO ratios in the range of 0.75 to 1.3. In fact, Comparative Example CE-D describes a PHD polyol with an NH / NCO ratio of 1.4, which results in an unstable dispersion with an excessively high PSD (d90). EX-8 and EX-9 both show embodiments of the invention in which high-MW aliphatic amines are used: EX-9 uses a monoamine that also contains a hydroxyl group, while in EX-8, the monoamine does not have an additional hydroxyl group (Jeffamine M-600 vs. DEOA). In EX-9, the aliphatic polyamine is bifunctional rather than trifunctional. Both examples show the formation of particles with low PSD (d90). EX-10 is an example carried out at a higher solids content (21% solids): again, in this case, the resulting polyol dispersion is characterized by a low PSD value (d90). EX-11 is an example carried out using a different type of base polyether polyol (all-PO polyol 2 has replaced EO / PO mixed feed polyol 1). Table 2

[0062] Table 2

[0063]

[0064] Viscosity is one aspect of the polyurea dispersions in embodiments of the present invention, which provides insight into the disclosure that not only should polyurea dispersions have low PSD, but they should also have low viscosity, such as that seen in, for example, EX 1 to EX 5. For example, considering EX 1, the resulting polyurea dispersion has approximately 2500 mPa at room temperature. . The viscosity of s; the basic polyol (polyol 1) has a viscosity of approximately 250 mPa. . The viscosity of s is such that, therefore, in the formation of polyurea dispersions, the viscosity ranges from approximately 250 mPa. . s has increased to approximately 2500 mPa . s, this is acceptable. On the other hand, in the case of CE B, the increase is from approximately 250 mPa. . s to approximately 11000 mPa. s, this is too high.

[0065] Table 3 below shows examples of polyurethane foams prepared using polyurea polyol dispersions. The polyurea polyols used have formulations as described in EX-11 of Table 2, and follow the procedures described in the polyurethane foam preparation process provided above.

[0066] The foam exhibits good overall properties, such as good compression set and the ability to pass fire tests, such as Class 1 IM. Table 3

[0067]

Claims

1. A method for forming a polyurea particle dispersion in a polyol, the method comprising: Provided are polyol dispersion formulations comprising: Basic polyols; Polyisocyanates; as well as An amine mixture, wherein the amine mixture comprises: 0.5% to 10% by weight (wt%) of a first aliphatic amine having an amine functionality of 1; 0.5% to 15% by weight of a second aliphatic amine having an amine functionality of 2 to 5; 0.3% to 7% by weight of an aromatic amine having an amine functionality of 1 to 4, wherein the percentage by weight is based on the total weight of the polyol dispersion formulation; as well as The mixture of the polyisocyanate and the amine is reacted in the base polyol at an NH / NCO equivalent ratio of 0.5 to 1.3 to form the polyurea particle dispersion in the polyol, the polyurea particle dispersion having a total solids content of 5% to 40% by weight based on the total weight of the polyurea particles in the polyol.

2. The method according to claim 1, wherein the base polyol is a polyether polyol having an equivalent weight of 200 g / equivalent to 3000 g / equivalent, and the polyether polyol is selected from the group consisting of: (a) the polyether polyol formed from 100% by weight propylene oxide (PO); (b) the polyether polyol formed from PO and having ends formed from ethylene oxide (EO); and (c) the polyether polyol formed from a mixture of PO and EO.

3. The method according to any one of claims 1 to 2, wherein the weight-average molecular weight of the first aliphatic amine and the weight-average molecular weight of the second aliphatic amine are independently in the range of 59 g / mol to 4000 g / mol, and the weight-average molecular weight of the aromatic amine is in another range of 95 g / mol to 1000 g / mol.

4. The method according to any one of claims 1 to 3, wherein the first aliphatic amine and the second aliphatic amine each comprise at least one group selected from the group consisting of: a hydroxyl moiety, a phosphorus moiety, and combinations thereof.

5. The method according to any one of claims 1 to 4, wherein the amine mixture comprises the first aliphatic amine, the second aliphatic amine, and the aromatic amine.

6. The method according to any one of claims 1 to 5, wherein the polyisocyanate and the amine mixture are reacted in the base polyol at an NH / NCO equivalent ratio of 0.75 to 1.3 to form the polyurea particle dispersion in the polyol.

7. The method according to any one of claims 1 to 6, wherein no catalyst is used in forming the polyurea particle dispersion in the polyol.

8. A polyol dispersion formed by the method according to any one of claims 1 to 7.

9. The polyol dispersion according to claim 8, wherein at least 90% by weight of the polyurea particles in the polyol have a diameter of 18 μm or less.

10. A polyurethane foam comprising a reaction product of a reaction mixture, the reaction mixture comprising: The polyol dispersion according to any one of claims 8 to 9; Foaming agent; and At least one polyisocyanate.

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