Polyol-containing composition and polyurethane foam

Abstract

To provide a polyol-containing composition that can prevent deterioration of catalytic activity while improving stability even when using hydrofluoroolefin as a foaming agent and can inhibit peeling caused between an object to be sprayed and polyurethane foam even when performing spraying construction under low temperature and to provide polyurethane foam using the polyol-containing composition.SOLUTION: The polyol-containing composition is used for producing polyurethane foam by reacting with polyisocyanate and contains polyol, a carboxylic acid ammonium salt represented by the general formula (1) as given below, a heterocyclic compound having a nitrogen atom, hydrofluoroolefin and a foam stabilizer. (In the general formula (1), R1 and R2 each independently represent an alkyl group; R3 represents a hydrogen atom or an alkyl group; and M+ represents a quaternary ammonium ion.)SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a polyol-containing composition and a polyurethane foam. [Background technology]

[0002] Conventionally, hydrofluorocarbons (HFCs) have been used as blowing agents for foaming polyurethane. However, because hydrofluorocarbons have a high global warming potential and there are moves to regulate them, switching to alternative materials is being considered. One such alternative material is hydrofluoroolefin (HFO). However, hydrofluoroolefins decompose the catalyst used in the production of polyurethane foam, reducing its activity, which causes the problem of the reaction between polyol and polyisocyanate not proceeding sufficiently. As a method for solving such problems, Patent Document 1 discloses a polyol premix composition containing a blowing agent, a polyol, a silicone surfactant, and a specific sterically hindered amine catalyst. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Special Publication No. 2011-500892 Summary of the Invention [Problem to be solved by the invention]

[0004] In order to improve the flame retardancy or render polyurethane foam non-flammable, it is necessary to increase the number of isocyanurate bonds by trimerization of polyisocyanate. Polyurethane foams are applied to building walls, for example, by spray application. However, if the catalyst activity is not sufficiently high, the reaction between the polyol and the polyisocyanate does not proceed sufficiently, resulting in lateral stretching of the polyurethane foam. This can lead to peeling between the foam and the target, especially when the target has corners. In particular, spray application at low temperatures around 0°C tends to reduce catalyst activity, making the above-mentioned peeling problem more likely to occur.

[0005] In contrast, Patent Document 1 is characterized by the use of a specific catalyst, but does not mention how, in polyurethane foams having isocyanurate bonds, the lateral expansion of the foam can be suppressed by increasing the catalytic activity. Furthermore, in order to obtain a polyurethane foam having a large number of isocyanurate bonds, it is necessary to use a trimerization catalyst and a resinification catalyst in combination. However, when a polyol-containing composition containing these catalysts is used with a hydrofluoroolefin, the stability decreases, and problems such as inadequate foaming are likely to occur.

[0006] Therefore, an object of the present invention is to provide a polyol-containing composition that can improve stability and prevent a decrease in catalytic activity, even when a trimerization catalyst and a resinification catalyst are used as catalysts and a hydrofluoroolefin is used as a blowing agent, and that is less likely to cause lateral stretching due to a decrease in catalytic activity, even when applied by spraying at low temperatures, for example. [Means for solving the problem]

[0007] As a result of extensive research conducted by the present inventors to solve the above problems, they found that when a specific ammonium carboxylate salt and a heterocyclic compound having a nitrogen atom are used in combination as a catalyst, the activity of the catalyst is not reduced and the stability of the polyol-containing composition is increased, even when a hydrofluoroolefin is used as a blowing agent, and thus completed the present invention.

[0008] The present invention is summarized as follows [1] to

[10] . [1] A polyol-containing composition for producing a polyurethane foam by reacting with a polyisocyanate, the polyol-containing composition containing a polyol, an ammonium carboxylate salt represented by the following general formula (1), a heterocyclic compound having a nitrogen atom, a hydrofluoroolefin, and a foam stabilizer: [ka] (In general formula (1), R 1 and R 2 each independently represents an alkyl group, and R 3 represents a hydrogen atom or an alkyl group. + represents a quaternary ammonium ion.) [2] The polyol-containing composition according to [1] above, wherein the amount of the ammonium carboxylate is 1 to 22 parts by mass per 100 parts by mass of the polyol. [3] R in the general formula (1) 3 The polyol-containing composition according to [1] or [2] above, wherein is an alkyl group. [4] M in the general formula (1) + The polyol-containing composition according to any one of the above [1] to [3], wherein is a tetramethylammonium ion. [5] The polyol-containing composition according to any one of the above [1] to [4], wherein the ammonium carboxylate represented by the general formula (1) is ammonium 2,2-dimethylpropanoate. [6] The polyol-containing composition according to any one of [1] to [5] above, wherein the amount of the heterocyclic compound having a nitrogen atom is 1 to 23 parts by mass per 100 parts by mass of the polyol. [7] The polyol-containing composition according to any one of the above [1] to [6], wherein the heterocyclic compound having a nitrogen atom is an imidazole derivative represented by the following general formula (2): [ka] (In general formula (2), R 4 and R 5 each independently represents an alkyl or alkenyl group having 1 to 8 carbon atoms. [8] The polyol-containing composition according to any one of the above [1] to [7], wherein the heterocyclic compound having a nitrogen atom is 1,2-dimethylimidazole. [9] A polyurethane foam which is a reaction product of the polyol-containing composition according to any one of the above [1] to [8] and a polyisocyanate.

[10] The polyurethane foam according to [9] above, having an isocyanate index of 200 or more. [Effects of the Invention]

[0009] According to the present invention, even when a trimerization catalyst and a resinification catalyst are used in combination as catalysts and a hydrofluoroolefin is used as a blowing agent, it is possible to provide a polyol-containing composition that can improve stability and prevent a decrease in catalytic activity, and that is less likely to develop lateral stretching even when applied by spraying at low temperatures, for example. DETAILED DESCRIPTION OF THE INVENTION

[0010] The present invention will be described in detail below. [Polyol-containing composition] The polyol-containing composition of the present invention is a polyol-containing composition for reacting with a polyisocyanate to obtain a polyurethane foam, and contains a polyol, an ammonium carboxylate salt represented by the following general formula (1), a heterocyclic compound having a nitrogen atom, a hydrofluoroolefin, and a foam stabilizer.

[0011] [ka] (In general formula (1), R 1 and R 2 each independently represents an alkyl group, and R 3 represents a hydrogen atom or an alkyl group. +represents a quaternary ammonium ion.)

[0012] The polyol-containing composition of the present invention uses a specific ammonium carboxylate salt and a heterocyclic compound having a nitrogen atom as catalysts in combination. Therefore, even when a hydrofluoroolefin is used as a blowing agent, the reaction between the polyol and the polyisocyanate can proceed rapidly without a decrease in catalyst activity while improving stability. As a result, even when spray application is performed at low temperatures, such as around 0°C, lateral expansion is suppressed and peeling is prevented. The two catalysts used in the present invention easily form six-membered ring isocyanurate bonds derived from the trimerized polyisocyanate by adjusting the amounts of polyol and polyisocyanate. Furthermore, polyurethane foams containing this six-membered ring isocyanurate bond form a char layer during combustion, making them less flammable, thereby improving the flame retardancy of the polyurethane foam.

[0013] <Polyol> The polyol-containing composition of the present invention contains a polyol as a raw material for polyurethane foam. Examples of polyols that can be used in the present invention include polylactone polyols, polycarbonate polyols, aromatic polyols, alicyclic polyols, aliphatic polyols, polyester polyols, polymer polyols, and polyether polyols.

[0014] Examples of polylactone polyols include polypropiolactone glycol, polycaprolactone glycol, and polyvalerolactone glycol. Examples of polycarbonate polyols include polyols obtained by dealcoholization reaction of hydroxyl group-containing compounds such as ethylene glycol, propylene glycol, butanediol, pentanediol, hexanediol, octanediol, and nonanediol with ethylene carbonate, propylene carbonate, and the like.

[0015] Examples of aromatic polyols include bisphenol A, bisphenol F, phenol novolac, and cresol novolac. Examples of alicyclic polyols include cyclohexanediol, methylcyclohexanediol, isophoronediol, dicyclohexylmethanediol, and dimethyldicyclohexylmethanediol. Examples of the aliphatic polyol include ethylene glycol, propylene glycol, butanediol, pentanediol, and hexanediol.

[0016] Examples of polyester polyols include polymers obtained by dehydration condensation of polybasic acids and polyhydric alcohols, polymers obtained by ring-opening polymerization of lactones such as ε-caprolactone and α-methyl-ε-caprolactone, and condensates of hydroxycarboxylic acids and the above-mentioned polyhydric alcohols. Examples of polybasic acids include adipic acid, azelaic acid, sebacic acid, isophthalic acid (m-phthalic acid), terephthalic acid (p-phthalic acid), and succinic acid. Examples of polyhydric alcohols include bisphenol A, ethylene glycol, 1,2-propylene glycol, 1,4-butanediol, diethylene glycol, 1,6-hexane glycol, and neopentyl glycol. Examples of hydroxycarboxylic acids include castor oil and reaction products of castor oil and ethylene glycol.

[0017] Examples of polymer polyols include polymers obtained by graft polymerizing an ethylenically unsaturated compound such as acrylonitrile, styrene, methyl acrylate, or methacrylate with an aromatic polyol, an alicyclic polyol, an aliphatic polyol, or a polyester polyol; polybutadiene polyol; and modified polyols of polyhydric alcohols or hydrogenated products thereof.

[0018] Examples of modified polyols of polyhydric alcohols include those obtained by reacting a raw material polyhydric alcohol with an alkylene oxide to modify it. Examples of polyhydric alcohols include trihydric alcohols such as glycerin and trimethylolpropane; tetrahydric to octahydric alcohols such as pentaerythritol, sorbitol, mannitol, sorbitan, diglycerin, and dipentaerythritol; sucrose, glucose, mannose, fructose, methyl glucoside, and derivatives thereof; polyols such as phloroglucinol, cresol, pyrogallol, catechol, hydroquinone, bisphenol A, bisphenol F, bisphenol S, 1,3,6,8-tetrahydroxynaphthalene, and 1,4,5,8-tetrahydroxyanthracene; polyfunctional polyols (e.g., having 2 to 100 functional groups) such as castor oil polyol, (co)polymers of hydroxyalkyl (meth)acrylate, and polyvinyl alcohol; and condensates of phenol and formaldehyde (novolak).

[0019] Although the method for modifying the polyhydric alcohol is not particularly limited, a method of adding alkylene oxide (hereinafter also referred to as "AO") is preferably used. Examples of AO include AOs having 2 to 6 carbon atoms, such as ethylene oxide (hereinafter also referred to as "EO"), 1,2-propylene oxide (hereinafter also referred to as "PO"), 1,3-propylene oxide, 1,2-butylene oxide, and 1,4-butylene oxide. Among these, PO, EO, and 1,2-butylene oxide are preferred from the viewpoints of properties and reactivity, and PO and EO are more preferred. When two or more AOs are used (for example, PO and EO), the addition method may be block addition, random addition, or a combination of these.

[0020] Examples of polyether polyols include polymers obtained by ring-opening polymerization of at least one alkylene oxide, such as ethylene oxide, propylene oxide, or tetrahydrofuran, in the presence of at least one low-molecular-weight active hydrogen compound having two or more active hydrogens. Examples of low-molecular-weight active hydrogen compounds having two or more active hydrogens include diols such as bisphenol A, ethylene glycol, propylene glycol, butylene glycol, and 1,6-hexanediol, triols such as glycerin and trimethylolpropane, and amines such as ethylenediamine and butylenediamine.

[0021] The polyol used in the present invention is preferably a polyester polyol or a polyether polyol from the viewpoint of suppressing the occurrence of lateral elongation. Furthermore, a polyol having two hydroxyl groups is preferred. Among these, polyester polyols obtained by dehydration condensation of a polybasic acid having an aromatic ring, such as isophthalic acid (m-phthalic acid) or terephthalic acid (p-phthalic acid), with a dihydric alcohol, such as bisphenol A, ethylene glycol, or 1,2-propylene glycol, are more preferred.

[0022] The hydroxyl value of the polyol is preferably 20 to 300 mgKOH / g, more preferably 30 to 250 mgKOH / g, and even more preferably 50 to 220 mgKOH / g. When the hydroxyl value of the polyol is equal to or less than the upper limit, the viscosity of the polyol-containing composition tends to decrease, which is preferable from the viewpoint of handleability, etc. On the other hand, when the hydroxyl value of the polyol is equal to or more than the lower limit, the crosslink density of the polyurethane foam increases, thereby increasing its strength. The hydroxyl value of the polyol can be measured in accordance with JIS K 1557-1:2007.

[0023] The polyol content in the polyol-containing composition of the present invention is preferably 10 to 80% by mass, more preferably 20 to 70% by mass, and even more preferably 25 to 60% by mass. A polyol content of at least the lower limit is preferred because it facilitates the reaction between the polyol and the polyisocyanate. On the other hand, a polyol content of at most the upper limit is preferred from the viewpoint of ease of handling because the viscosity of the polyol-containing composition does not become too high.

[0024] <Ammonium Carboxylate Salt Represented by General Formula (1) (Trimerization Catalyst)> The polyol-containing composition of the present invention contains an ammonium carboxylate salt represented by the following general formula (1) as a polyisocyanate trimerization catalyst. The ammonium carboxylate salt represented by the following general formula (1) has moderate steric hindrance and is therefore less susceptible to the influence of hydrofluoroolefin, preventing a decrease in catalytic activity. Therefore, even when a hydrofluoroolefin is used as a blowing agent, it is possible to suppress the problem of lateral expansion during spray application. Furthermore, in the present invention, the ammonium carboxylate salt represented by the following general formula (1) is used in combination with a heterocyclic compound having a nitrogen atom, which will be described later, and therefore it is easy to form an isocyanurate bond by the polyisocyanate trimer, making it possible to obtain a polyurethane foam with excellent flame retardancy.

[0025] [ka] (In general formula (1), R 1 and R 2 each independently represents an alkyl group, and R 3 represents a hydrogen atom or an alkyl group. + represents a quaternary ammonium ion.)

[0026] R in general formula (1) 1 and R 2are each independently an alkyl group, and specifically, an alkyl group having 1 to 6 carbon atoms is preferable, an alkyl group having 1 to 4 carbon atoms is more preferable, and an alkyl group having 1 to 2 carbon atoms is even more preferable. The alkyl group may be linear or may have a branched structure. Also, R 3 represents a hydrogen atom or an alkyl group, and the alkyl group preferably has 1 to 6 carbon atoms. 3 is preferably an alkyl group, more preferably an alkyl group having 1 to 4 carbon atoms, and even more preferably an alkyl group having 1 to 2 carbon atoms. R 1 , R 2 and R 3 If the number of carbon atoms in R is equal to or greater than the lower limit, the steric hindrance becomes large, and the effect of the hydrofluoroolefin becomes less likely. 1 , R 2 and R 3 When the number of carbon atoms is equal to or less than the upper limit, steric hindrance does not become too large, and it is possible to prevent the reaction between the polyol and the polyisocyanate from becoming extremely slow.

[0027] M + represents a quaternary ammonium ion, and examples thereof include a tetramethylammonium ion, a tetraethylammonium ion, and a triethylmonomethylammonium ion. Of these, the tetramethylammonium ion and the triethylmonomethylammonium ion are preferred, and the tetramethylammonium ion is more preferred.

[0028] Specific examples of the ammonium carboxylate represented by the general formula (1) include R 1 , R 2 and R 3 are all methyl groups, and M + 2,2-dimethylpropanoic acid tetramethylammonium salt, where R is the tetramethylammonium ion 1 , R 2 and R 3 are all methyl groups, and M +and ammonium 2,2-dimethylpropanoate such as triethylmonomethylammonium 2,2-dimethylpropanoate, in which the carboxylate is a triethylmonomethylammonium ion. Among these, tetramethylammonium 2,2-dimethylpropanoate is preferred. In the present invention, the ammonium carboxylate may be used alone or in combination of two or more thereof.

[0029] The amount of ammonium carboxylate salt in the polyol-containing composition is preferably 1 to 22 parts by mass, more preferably 2 to 19 parts by mass, even more preferably 4 to 17 parts by mass, even more preferably 4 to 14 parts by mass, and even more preferably 4 to 11 parts by mass, per 100 parts by mass of polyol. When the amount of ammonium carboxylate salt is equal to or greater than the lower limit, trimerization of polyisocyanate is likely to occur, improving the flame retardancy of the resulting polyurethane foam. On the other hand, when the amount of ammonium carboxylate salt is equal to or less than the upper limit, it becomes easier to control the reaction.

[0030] <Heterocyclic compounds containing nitrogen atoms (resinification catalysts)> The polyol-containing composition of the present invention contains a heterocyclic compound having a nitrogen atom as a resinification catalyst. When the polyol-containing composition contains a heterocyclic compound having a nitrogen atom as a resinification catalyst, the polyol-containing composition is less susceptible to the influence of hydrofluoroolefin, and the stability is improved, and the reaction between the polyol and the polyisocyanate is facilitated, making it easier to prevent lateral elongation and the like.

[0031] Although there is no particular limitation on the heterocyclic compound having a nitrogen atom used in the present invention, a compound containing a nitrogen atom in the heterocycle is preferred, for example, a 4- to 8-membered heterocyclic compound containing a nitrogen atom in the heterocycle is more preferred, more specifically, imidazole derivatives, pyridine derivatives, piperazine derivatives, etc. Among these, imidazole derivatives are preferred, and imidazole derivatives represented by the following general formula (2) are more preferred.

[0032] [ka] (In general formula (2), R 4 and R 5 each independently represents an alkyl or alkenyl group having 1 to 8 carbon atoms.

[0033] R in the general formula (2) 4 and R 5 R each independently represents an alkyl group or alkenyl group having 1 to 8 carbon atoms, preferably an alkyl group or alkenyl group having 1 to 6 carbon atoms, more preferably an alkyl group having 1 to 4 carbon atoms. 4 and R 5 When the number of carbon atoms in the alkyl group or alkenyl group in R is equal to or greater than the lower limit, steric hindrance increases and the group is less susceptible to the influence of the hydrofluoroolefin, which is preferable. 4 and R 5 When the number of carbon atoms in the alkyl or alkenyl group is equal to or less than the upper limit, the steric hindrance is not excessively large, and therefore the reaction between the polyol and the polyisocyanate can proceed quickly. The alkyl and alkenyl groups may each be linear or have a branched structure. Examples of the imidazole derivative represented by general formula (2) include 1,2-dimethylimidazole, 1-ethyl-2-methylimidazole, 1-methyl-2-ethylimidazole, 1,2-diethylimidazole, and 1-isobutyl-2-methylimidazole. Among them, 1,2-dimethylimidazole and 1-isobutyl-2-methylimidazole are preferred from the viewpoint of improving the activity of the catalyst in the presence of hydrofluoroolefin and promoting the reaction rapidly. Furthermore, 1,2-dimethylimidazole is even more preferred from the viewpoint of further enhancing stability.

[0034] The amount of the heterocyclic compound having a nitrogen atom in the polyol-containing composition is preferably 1 to 23 parts by mass, more preferably 3 to 19 parts by mass, even more preferably 5 to 15 parts by mass, and even more preferably 5 to 11 parts by mass, per 100 parts by mass of the polyol. When the amount of the heterocyclic compound having a nitrogen atom is equal to or greater than the lower limit, urethane bond formation occurs more easily, and the reaction proceeds rapidly. On the other hand, when the amount of the heterocyclic compound having a nitrogen atom is equal to or less than the upper limit, the reaction rate can be easily controlled, which is preferable.

[0035] <Hydrofluoroolefin (blowing agent)> The polyol-containing composition of the present invention contains a hydrofluoroolefin as a blowing agent. Examples of hydrofluoroolefins include fluoroalkenes having about 3 to 6 carbon atoms. The hydrofluoroolefin may be a hydrochlorofluoroolefin having a chlorine atom, and therefore may be a chlorofluoroalkene having about 3 to 6 carbon atoms. More specific examples include trifluoropropene, tetrafluoropropenes such as HFO-1234, pentafluoropropenes such as HFO-1225, chlorotrifluoropropenes such as HFO-1233, chlorodifluoropropene, chlorotrifluoropropene, and chlorotetrafluoropropene. More specific examples include 1,3,3,3-tetrafluoropropene (HFO-1234ze), 1,1,3,3-tetrafluoropropene, 1,2,3,3,3-pentafluoropropene (HFO-1225ye), 1,1,1-trifluoropropene, 1,1,1,3,3-pentafluoropropene (HFO-1225zc), 1,1,1,3,3,3-hexafluorobut-2-ene, 1,1,2,3,3-pentafluoropropene (HFO-1225yc), 1,1,1,2,3-pentafluoropropene (HFO-1225yez), 1-chloro-3,3,3-trifluoropropene (HFO-1233zd), and 1,1,1,4,4,4-hexafluorobut-2-ene. Of these, HFO-1233zd is preferred. These hydrofluoroolefins may be used alone or in combination of two or more.

[0036] The global warming potential (GWP) of the hydrofluoroolefin used in the present invention is preferably not more than 150, more preferably not more than 100, and even more preferably not more than 75. Note that "GWP" is a value defined in "The Scientific Assessment of Ozone Depletion, 2002, a report of the World Meteorological Association's Global Ozone Research and Monitoring Project," and is a value measured relative to the GWP of carbon dioxide on a 100-year time scale. Furthermore, the ozone depletion potential (ODP) of the hydrofluoroolefin is preferably 0.05 or less, more preferably 0.02 or less, and even more preferably substantially 0. Incidentally, "ODP" is a value defined in "The Scientific Assessment of Ozone Depletion, 2002, A report of the World Meteorological Association's Global Ozone Research and Monitoring Project."

[0037] The amount of hydrofluoroolefin blended is preferably 10 to 60 parts by mass, more preferably 20 to 55 parts by mass, even more preferably 25 to 50 parts by mass, and even more preferably 30 to 45 parts by mass, per 100 parts by mass of polyol. When the amount of hydrofluoroolefin blended is equal to or greater than the lower limit, foaming is promoted, and the density of the resulting polyurethane foam can be reduced. On the other hand, when the amount of hydrofluoroolefin blended is equal to or less than the upper limit, excessive foaming can be suppressed.

[0038] <Blowing agents other than hydrofluoroolefins> The polyol-containing composition of the present invention may contain a blowing agent other than hydrofluoroolefin.Examples of blowing agents other than hydrofluoroolefin include low-boiling hydrocarbons such as water, propane, butane, pentane, hexane, heptane, cyclopropane, cyclobutane, cyclopentane, cyclohexane, and cycloheptane, chlorinated aliphatic hydrocarbon compounds such as dichloroethane, propyl chloride, isopropyl chloride, butyl chloride, isobutyl chloride, pentyl chloride, and isopentyl chloride, and other organic physical blowing agents such as ether compounds such as diisopropyl ether, and inorganic physical blowing agents such as nitrogen gas, oxygen gas, argon gas, and carbon dioxide gas.Among these, water, oxygen gas, and carbon dioxide gas are preferred from the viewpoint of ease of handling, and water is preferred from the viewpoint of adjusting the isocyanate index and ease of handling.

[0039] The amount of the blowing agent other than the hydrofluoroolefin in the polyol-containing composition is preferably 0.01 to 10 parts by mass, more preferably 0.1 to 5 parts by mass, and even more preferably 0.5 to 2 parts by mass, per 100 parts by mass of the polyol. When the amount of the blowing agent is equal to or greater than the lower limit, foaming is promoted, and the density of the resulting polyurethane foam can be reduced. On the other hand, when the amount of the blowing agent is equal to or less than the upper limit, excessive foaming can be suppressed.

[0040] <Foam stabilizer> The polyol-containing composition of the present invention contains a foam stabilizer for the purpose of facilitating foaming of the mixture of the polyol-containing composition and the isocyanate. Examples of the foam stabilizer include surfactants such as polyoxyalkylene foam stabilizers such as polyoxyalkylene alkyl ethers, and silicone foam stabilizers such as organopolysiloxanes. These foam stabilizers may be used alone or in combination of two or more.

[0041] The amount of foam stabilizer in the polyol-containing composition of the present invention is preferably 0.1 to 10 parts by mass, more preferably 1 to 8 parts by mass, and even more preferably 1 to 5 parts by mass, per 100 parts by mass of polyol. When the amount of foam stabilizer is equal to or greater than the lower limit, the mixture of the polyol-containing composition and the polyisocyanate is easily foamed, making it possible to obtain a homogeneous polyurethane foam. When the amount of foam stabilizer is equal to or less than the upper limit, the balance between production costs and the obtained effects is optimal.

[0042] <Flame retardant> The polyol-containing composition of the present invention may contain a flame retardant. A polyurethane foam produced using the polyol-containing composition of the present invention has excellent flame retardancy because it contains an isocyanurate bond formed by the trimerization of polyisocyanate, and the flame retardancy of the polyurethane foam can be further improved by using a flame retardant. The flame retardant used in the present invention is preferably red phosphorus, phosphate ester, phosphate-containing flame retardant, bromine-containing flame retardant, boric acid-containing flame retardant, antimony-containing flame retardant, metal hydroxide, etc., and more preferably red phosphorus, phosphate ester, phosphate-containing flame retardant, bromine-containing flame retardant, boric acid-containing flame retardant, antimony-containing flame retardant, and metal hydroxide.

[0043] As the phosphate ester, it is preferable to use a monophosphate ester, a condensed phosphate ester, or the like, and examples thereof include trimethyl phosphate, triethyl phosphate, tributyl phosphate, tri(2-ethylhexyl) phosphate, tributoxyethyl phosphate, triphenyl phosphate, tricresyl phosphate, trixylenyl phosphate, tris(isopropylphenyl)phosphate, tris(phenylphenyl)phosphate, trinaphthyl phosphate, cresyl diphenyl phosphate, xylenyl diphenyl phosphate, diphenyl(2-ethylhexyl)phosphate, di(isopropylphenyl)phenyl phosphate, monoisopropyl phosphate, Examples of the phosphate phosphate include decyl phosphate, 2-acryloyloxyethyl acid phosphate, 2-methacryloyloxyethyl acid phosphate, diphenyl-2-acryloyloxyethyl phosphate, diphenyl-2-methacryloyloxyethyl phosphate, melamine phosphate, dimelamine phosphate, melamine pyrophosphate, triphenylphosphine oxide, tricresylphosphine oxide, diphenyl methanephosphonate, diethyl phenylphosphonate, resorcinol bis(diphenyl phosphate), bisphenol A bis(diphenyl phosphate), phosphaphenanthrene, and tris(β-chloropropyl) phosphate.

[0044] Examples of condensed phosphate esters include trialkyl polyphosphate, resorcinol polyphenyl phosphate, resorcinol poly(di-2,6-xylyl) phosphate (manufactured by Daihachi Chemical Industry Co., Ltd., product name PX-200), hydroquinone poly(2,6-xylyl) phosphate, and condensates thereof.

[0045] Among these, monophosphate esters are preferred, and tris(β-chloropropyl)phosphate is more preferred, from the viewpoint of reducing the viscosity of the mixture of the polyol-containing composition and the polyisocyanate to facilitate production, and from the viewpoint of improving the flame retardancy of the polyurethane foam.

[0046] When the polyol-containing composition of the present invention contains a flame retardant, the blending amount thereof is preferably 10 to 150 parts by mass, more preferably 20 to 140 parts by mass, even more preferably 30 to 130 parts by mass, and even more preferably 40 to 125 parts by mass, per 100 parts by mass of polyol. When the blending amount of the flame retardant is equal to or greater than the lower limit, sufficient flame retardancy can be imparted to a polyurethane foam produced using the polyol-containing composition. On the other hand, when the blending amount of the flame retardant is equal to or less than the upper limit, foaming during production of the polyurethane foam is not inhibited.

[0047] <Other ingredients> In the present invention, a trimerization catalyst may be contained in addition to the ammonium carboxylate represented by the general formula (1). Examples of such catalysts include metal salts of carboxylic acids represented by the general formula (1). Also included are ammonium salts and metal salts of carboxylic acids having structures other than those represented by the general formula (1). When a metal salt is contained, the ammonium carboxylate represented by the general formula (1) may partially become a metal salt of the carboxylic acid.

[0048] The polyol-containing composition of the present invention may contain components other than the polyol, the ammonium carboxylate represented by general formula (1), the heterocyclic compound having a nitrogen atom, the hydrofluoroolefin, and the foam stabilizer, and may contain, for example, an inorganic filler. Examples of inorganic fillers include silica, diatomaceous earth, alumina, titanium oxide, calcium oxide, magnesium oxide, iron oxide, tin oxide, antimony oxide, ferrites, basic magnesium carbonate, calcium carbonate, magnesium carbonate, zinc carbonate, barium carbonate, dawsonite, hydrotalcite, calcium sulfate, barium sulfate, gypsum fiber, calcium silicate, talc, clay, mica, wollastonite, montmorillonite, bentonite, activated clay, sepiolite, imogolite, sericite, glass fiber, glass beads, silica palan, aluminum nitride, boron nitride, silicon nitride, carbon black, graphite, carbon fiber, carbon palan, charcoal powder, various metal powders, potassium titanate, magnesium sulfate, lead zirconate titanate, aluminum borate, molybdenum sulfide, silicon carbide, stainless steel fiber, various magnetic powders, slag fiber, fly ash, silica alumina fiber, alumina fiber, silica fiber, and zirconia fiber. These inorganic fillers may be used alone or in combination of two or more. The polyol-containing composition of the present invention may or may not contain an inorganic filler. When the polyol-containing composition contains an inorganic filler, the amount of the inorganic filler is preferably 1 to 100 parts by mass, more preferably 10 to 80 parts by mass, and even more preferably 20 to 70 parts by mass, per 100 parts by mass of the polyol.

[0049] Furthermore, the polyol-containing composition may contain, as needed, one or more selected from phenol-based, amine-based, sulfur-based, and other antioxidants, heat stabilizers, metal inhibitors, antistatic agents, stabilizers, crosslinking agents, lubricants, softeners, pigments, and the like, within the scope of the present invention.

[0050] <Method of producing polyol-containing composition> There are no particular limitations on the method for producing the polyol-containing composition of the present invention, and it can be produced, for example, by stirring each component at about 20 to 40°C for about 30 seconds to 20 minutes using a homodisper or the like.

[0051] [Polyurethane foam] The polyurethane foam of the present invention is a reaction product of the polyol-containing composition of the present invention and a polyisocyanate. As described above, the polyol-containing composition of the present invention uses a specific ammonium carboxylate salt and a heterocyclic compound having a nitrogen atom as catalysts, so that even when a hydrofluoroolefin is used as a blowing agent, the composition is highly stable and the catalytic activity is not easily reduced. Therefore, the polyurethane foam of the present invention can suppress the problem of lateral expansion even when sprayed at low temperatures.

[0052] <Polyisocyanate> Examples of polyisocyanates include aromatic polyisocyanates, alicyclic polyisocyanates, and aliphatic polyisocyanates. Examples of aromatic polyisocyanates include phenylene diisocyanate, tolylene diisocyanate, xylylene diisocyanate, diphenylmethane diisocyanate, dimethyldiphenylmethane diisocyanate, triphenylmethane triisocyanate, naphthalene diisocyanate, and polymethylene polyphenyl polyisocyanate.

[0053] Examples of alicyclic polyisocyanates include cyclohexylene diisocyanate, methylcyclohexylene diisocyanate, isophorone diisocyanate, dicyclohexylmethane diisocyanate, and dimethyldicyclohexylmethane diisocyanate.

[0054] Examples of the aliphatic polyisocyanate include methylene diisocyanate, ethylene diisocyanate, propylene diisocyanate, tetramethylene diisocyanate, and hexamethylene diisocyanate.

[0055] Among these, from the viewpoints of ease of use and availability, aromatic polyisocyanates are preferred, and diphenylmethane diisocyanate is more preferred. One type of polyisocyanate may be used alone, or two or more types may be used in combination. Furthermore, known additives that are typically added to polyisocyanates may be appropriately added to the polyisocyanate before it is mixed with the polyol-containing composition.

[0056] It is preferable that the polyol-containing composition and the polyisocyanate mixed therein have substantially the same volume. Specifically, the volume ratio of the polyisocyanate to the polyol-containing composition is preferably 0.8 to 1.2, more preferably 0.9 to 1.1, and even more preferably 0.95 to 1.05.

[0057] <Isocyanate Index> The isocyanate index of the polyurethane foam of the present invention is not particularly limited, but is preferably 200 or higher. If the isocyanate index is equal to or higher than the lower limit, the amount of polyisocyanate relative to the polyol becomes excessive, facilitating the formation of isocyanurate bonds due to the polyisocyanate trimer, resulting in improved flame retardancy of the polyurethane foam. It also makes it possible to impart non-flammability. Furthermore, when the isocyanate index is equal to or higher than the lower limit, combined with the use of an ammonium carboxylate salt and a heterocyclic compound having a nitrogen atom, it is easy to produce a polyurethane foam having isocyanurate bonds, i.e., a polyurethane foam that combines high levels of flame retardancy and thermal insulation. From these perspectives, the isocyanate index is more preferably 250 or higher, even more preferably 300 or higher, and particularly preferably 400 or higher. The isocyanate index is preferably not more than 1000, more preferably not more than 800, and even more preferably not more than 600. When the isocyanate index is not more than the upper limit, the resulting polyurethane foam will have a good balance between flame retardancy and production costs.

[0058] The isocyanate index can be calculated by the following method. Isocyanate Index = number of equivalents of polyisocyanate ÷ (number of equivalents of polyol + number of equivalents of water) × 100 Here, each equivalent number can be calculated as follows: Polyisocyanate equivalent number = Amount of polyisocyanate used (g) × NCO content (mass%) / Molecular weight of NCO (mol) × 100 Equivalent weight of polyol = OHV × amount of polyol used (g) ÷ molecular weight of KOH (mmol) OHV is the hydroxyl value of the polyol (mg KOH / g). Equivalents of water = Amount of water used (g) / Molecular weight of water (moles) × Number of OH groups in water In the above formulas, the molecular weight of NCO is 42 (mol), the molecular weight of KOH is 56,100 (mmol), the molecular weight of water is 18 (mol), and the number of OH groups in water is 2.

[0059] <Method of manufacturing polyurethane foam> Although there are no particular limitations on the method for producing the polyurethane foam of the present invention, it is preferable to mix a polyisocyanate and a polyol-containing composition, foam them, and allow them to react. Specifically, it is preferable to impinge-mix the polyisocyanate and the polyol-containing composition using a spray gun or the like, and then spray them. More specifically, the polyurethane foam can be produced by mixing the polyisocyanate and the polyol-containing composition at a liquid temperature of approximately 10 to 50°C using a spray gun, spraying the mixture onto the surface to be treated at a discharge pressure of approximately 800 to 2000 psi, and foaming. In addition, since a specific ammonium carboxylate salt and a heterocyclic compound having a nitrogen atom are used as catalysts in the present invention, the catalyst activity can be maintained even under low ambient temperature conditions. Therefore, polyurethane foam can be produced without problems even when foaming and curing at low ambient temperatures of approximately 0 to 15°C. In the present invention, the polyurethane foam may be obtained by mixing the polyisocyanate and the polyol-containing composition, pouring the mixture into a container such as a mold or frame, and curing the mixture.

[0060] <Applications of polyurethane foam> The uses of the polyurethane foam of the present invention are not particularly limited, but because of its excellent flame retardancy and heat insulation, it can be suitably used in buildings such as walls, ceilings, roofs, and floors of buildings. It can also be suitably used as a member for filling any openings that occur in buildings, including joints and holes that occur between structural members of buildings. [Example]

[0061] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples.

[0062] <Materials used> [Polyisocyanate] 4,4'-Diphenylmethane diisocyanate (4,4'-MDI) (Manka Chemical Japan Co., Ltd., product name: PM200) [Polyol] p-Phthalic acid polyester polyol (Kawasaki Chemical Industries, Ltd., product name: Maximol RLK-087, hydroxyl value = 200 mg KOH / g) [Trimerization catalyst] Ammonium carboxylates 2,2-dimethylpropanoic acid tetramethylammonium salt (Evonik Japan Co., Ltd., product name: DABCO TMR-7), a mixture with ethylene glycol (2,2-dimethylpropanoic acid tetramethylammonium salt 45 to 55 mass%, ethylene glycol 45 to 55 mass%) ·Comparative trimerization catalyst (1) Tetramethylammonium acetate (manufactured by Tosoh Corporation, product name: TOYOCAT (registered trademark)-TRX) ·Comparative trimerization catalyst (2) 2-Ethylhexanoic acid potassium salt (manufactured by Evonik Japan Co., Ltd., product name: DABCO K-15)

[0063] [Resinification catalyst] Heterocyclic compounds (1) 1,2-dimethylimidazole (manufactured by Tosoh Corporation, product name: TOYOCAT (registered trademark)-DM70, a mixture with ethylene glycol (65 to 75% by mass of 1,2-dimethylimidazole, 25 to 35% by mass of ethylene glycol) Heterocyclic compounds (2) 1-Isobutyl-2-methylimidazole (manufactured by Evonik Japan Co., Ltd., product name: NICM) ·Resinization catalyst for comparison (1) N,N,N',N'',N''-Pentamethyldiethylenetriamine (manufactured by Tosoh Corporation, product name: TOYOCAT (registered trademark)-TT)

[0064] [Blowing Agent] Hydrofluoroolefin (Honeywell Japan, product name: Solstice LBA, trans-1-chloro-3,3,3-trifluoropropene) ·water [Foam stabilizer] Silicone foam stabilizer (manufactured by Toray Dow Corning Co., Ltd., product name: SH-193, octamethylcyclotetrasiloxane)

[0065] [Flame retardant] Tris(β-chloropropyl)phosphate (manufactured by Daihachi Chemical Industry Co., Ltd., product name: TMCPP) [Inorganic filler] Calcium silicate (Kinsematec Co., Ltd., product name: SH1250)

[0066] <Examples 1 to 9 and Comparative Examples 1 to 3> A polyol-containing composition was prepared by stirring the components according to the formulation shown in Table 1 at a rotation speed of 3600 rpm for 10 minutes using a homodisper so that the total amount of each component was 10 L.

[0067] <Stability in the presence of hydrofluoroolefins> First, the polyol-containing composition prepared by the above method and polyisocyanate were mixed in a homodisper according to the formulation shown in Table 1, and the cream time and gel time of the resulting mixture were measured in the following manner. Next, for comparison, a polyol mixed solution prepared separately by the above method was placed in a pressure-resistant container and stored in a thermostatic bath at 60° C. for 3 days. Next, this polyol mixed solution and polyisocyanate were mixed using a homodisper, and the cream time and gel time of the resulting mixture were measured as follows. The measurement results for a polyol-containing composition prepared without storing it in a thermostatic chamber for three days were compared with the measurement results after storage. If the difference between the two was less than 10% for both the cream time and gel time, it was rated as "5," if both were less than 20%, it was rated as "4," if both were less than 30%, it was rated as "3," if both were less than 40%, it was rated as "2," and all other cases were rated as "1." The results are shown in Table 1.

[0068] [Cream Time] Cream time refers to the time (seconds) from the start of stirring and mixing the polyol-containing composition and the isocyanate until the mixture becomes creamy and cloudy. [Gel time] The gel time is the time (seconds) from mixing the reactant stock solution until the foam becomes stringy when a stick is pierced into the foam during foaming.

[0069] <Horizontal stretch> The polyurethane resin composition prepared by the above method was sprayed onto an L-shaped substrate (gypsum board) at a low temperature (0°C). One day after spraying, the interface between the polyurethane resin and the substrate was observed, and the evaluation was performed using a scale of "5" if no peeling occurred, "4" if less than 10% of the peeled area was peeled, "3" if less than 30% of the peeled area was peeled, "2" if less than 50% of the peeled area was peeled, and "1" if 50% or more of the peeled area was peeled. The results are shown in Table 1.

[0070] [Table 1]

[0071] *In Table 1, the parts by mass of ammonium carboxylate and the parts by mass of heterocyclic compound (1) indicate the blending amounts of the mixture with ethylene glycol.

[0072] In all examples and comparative examples, the volume ratio of polyisocyanate to polyol-containing composition was 1.

[0073] As is clear from the results of the above examples, the polyol-containing composition of the present invention, when a specific ammonium carboxylate and a heterocyclic compound having a nitrogen atom were used in combination as catalysts, exhibited good stability and sufficiently prevented lateral elongation, even when a hydrofluoroolefin was used as a blowing agent.

Claims

1. A polyol-containing composition for producing a polyurethane foam by reacting with a polyisocyanate, the composition comprising a polyol, an ammonium carboxylate salt represented by the following general formula (1), an imidazole derivative represented by the following general formula (2), a hydrofluoroolefin, and a foam stabilizer: the blending amount of the ammonium carboxylate is 1 to 22 parts by mass relative to 100 parts by mass of the polyol, A polyol-containing composition in which the blending amount of the imidazole derivative is 1 to 23 parts by mass relative to 100 parts by mass of the polyol (however, excluding compositions containing the product names "TOYOCAT (registered trademark)-TRX" and "TOYOCAT (registered trademark)-TT", and compositions containing one or more vinyl polymerizable compounds selected from the group consisting of the following (Z1) to (Z3), which have a vinyl polymerizable functional group represented by the following general formula (3) and have a concentration of the vinyl polymerizable functional group in the molecule of 0.5 to 20 (mmol / g)). 【Chemical 1】 (In general formula (1), R １ and R ２ each independently represents an alkyl group, R ３ represents a hydrogen atom or an alkyl group. ＋ represents a quaternary ammonium ion.) 【Chemistry 2】 (In general formula (2), R ４ and R ５ each independently represents an alkyl or alkenyl group having 1 to 8 carbon atoms. 【Chemistry 3】 (In general formula (3), R represents hydrogen, an alkyl group having 1 to 15 carbon atoms, or an aryl group having 6 to 21 carbon atoms.) (Z1) Unsaturated carboxylic acid ester or unsaturated alkyl ether of polyol (Z2) Unsaturated carboxylic acid amidation product or unsaturated alkylation product of amine (Z3) Unsaturated carboxylic acid thioester or unsaturated alkyl thioether of polythiol

2. M in the general formula (1) ＋ The polyol-containing composition of claim 1 , wherein is a tetramethylammonium ion.

3. 3. The polyol-containing composition according to claim 1, wherein the ammonium carboxylate represented by the general formula (1) is ammonium 2,2-dimethylpropanoate.

4. The polyol-containing composition according to any one of claims 1 to 3, wherein the imidazole derivative is 1,2-dimethylimidazole.

5. A polyurethane foam which is a reaction product of the polyol-containing composition according to any one of claims 1 to 4 and a polyisocyanate.

6. 6. The polyurethane foam according to claim 5, having an isocyanate index of 200 or greater.

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