JP7478048B2 - Polyol-containing composition, foamable polyurethane composition, and polyurethane foam - Google Patents

Description

The present invention relates to a polyol-containing composition, a foamable polyurethane composition, and a polyurethane foam.

Due to its excellent heat insulating and adhesive properties, polyurethane foam is used as a heat insulating material for buildings such as apartment complexes, detached houses, various school facilities, and commercial buildings. Polyurethane foam is obtained by mixing a polyol-containing composition with a polyisocyanate and foaming the mixture.

The polyol-containing composition contains a resinification catalyst, a trimerization catalyst, etc. as catalysts. The resinification catalyst is a catalyst that promotes the reaction between a polyol, etc. and an isocyanate, and the trimerization catalyst is a catalyst that promotes the production of isocyanurate by the reaction of isocyanates with each other, thereby increasing the ratio of isocyanurate.
In the polyol-containing composition containing a catalyst, the catalyst and the blowing agent may react during storage, causing a decrease in catalytic performance and a decrease in foaming property. Hydrofluorocarbons (HFCs) have been widely used as blowing agents in the past, but the switch to hydrofluoroolefins (HFOs) with low global warming potential as blowing agents is progressing. Hydrofluoroolefins, among blowing agents, tend to react particularly easily with catalysts, which makes the decrease in catalytic performance and the decrease in foaming property more likely to occur.
As methods for solving such problems, a method of specifying the blending amounts of a trimerization catalyst and a resinification catalyst (see, for example, Patent Document 1) and a method of using a trimerization catalyst having a predetermined structure (see, for example, Patent Document 2) have been proposed.

JP 2018-30975 A, International Publication No. 2018/105730

However, with conventional polyol-containing compositions, it is difficult to achieve both stability against the blowing agent catalyst and improved foamability.

The present invention has been made in consideration of the above problems, and aims to provide a polyol-containing composition, a foamable polyurethane composition, and a polyurethane foam that have both stability against the catalyst of the blowing agent and good foamability.

As a result of intensive research conducted by the present inventors to solve the above problems, they discovered that the above problems could be solved by incorporating, as a catalyst, an ammonium carboxylate salt, which is a quaternary ammonium salt of a carboxylic acid having 5 or more carbon atoms, a heterocyclic compound having a nitrogen atom, and a transition metal salt, and thus completed the present invention described below.

The present invention relates to the following items [1] to [17].
[1] A polyol-containing composition for producing a polyurethane foam by reacting with a polyisocyanate, comprising a polyol, a blowing agent, and a catalyst,
The catalyst is a polyol-containing composition that contains a carboxylate ammonium salt, which is a quaternary ammonium salt of a carboxylic acid having 5 or more carbon atoms, a heterocyclic compound having a nitrogen atom, and a transition metal salt.
[2] The polyol-containing composition according to [1], wherein the carboxylic acid in the ammonium carboxylate is at least one selected from the group consisting of 2-ethylhexanoic acid and 2,2-dimethylpropanoic acid.
[3] The polyol-containing composition according to [1] or [2], wherein the quaternary ammonium ion in the ammonium carboxylate is at least one selected from the group consisting of triethylmethylammonium ion and tetramethylammonium ion.
[4] The polyol-containing composition according to any one of [1] to [3], wherein the ammonium carboxylate is 2,2-dimethylpropanoic acid tetramethylammonium salt.
[5] The polyol-containing composition according to any one of [1] to [4], wherein the heterocyclic compound is an imidazole derivative.
[6] The polyol-containing composition according to any one of [1] to [5], wherein the imidazole derivative is an imidazole in which the 1- and 2-positions are each independently substituted with an alkyl group having 4 or less carbon atoms.
[7] The polyol-containing composition according to any one of [1] to [6], wherein the imidazole derivative is at least one selected from the group consisting of 1,2-dimethylimidazole and 1-isobutyl-2-methylimidazole.
[8] The polyol-containing composition according to any one of [1] to [7], wherein the imidazole derivative is 1,2-dimethylimidazole.
[9] The polyol-containing composition according to any one of [1] to [8], wherein the transition metal in the transition metal salt is at least one selected from the group consisting of bismuth and tin.
[10] The polyol-containing composition according to any one of [1] to [9], wherein the transition metal salt is a metal salt of a carboxylic acid having 5 or more carbon atoms.
[11] The polyol-containing composition according to any one of [1] to [10], wherein the transition metal in the transition metal salt is bismuth.
[12] The polyol-containing composition according to any one of [1] to [11], wherein the transition metal salt is a metal salt of octylic acid.
[13] The polyol-containing composition according to any one of [1] to [12], wherein the blowing agent is a hydrofluoroolefin.
[14] The polyol-containing composition according to any one of [1] to [13], which contains a foam stabilizer.
[15] A foamable polyurethane composition comprising the polyol-containing composition according to any one of [1] to [14] and a polyisocyanate.
[16] The foamable polyurethane composition according to [15], having an isocyanate index of 250 or more.
[17] A polyurethane foam obtained by reacting and foaming the foamable polyurethane composition according to [15] or [16].

The present invention can provide a polyol-containing composition, a foamable polyurethane composition, and a polyurethane foam that have both good foaming properties and stability against the blowing agent catalyst.

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 obtaining a polyurethane foam by reacting with a polyisocyanate, and contains a polyol, a blowing agent, and a catalyst, and the catalyst contains an ammonium carboxylate salt which is a quaternary ammonium salt of a carboxylic acid having 5 or more carbon atoms, a heterocyclic compound having a nitrogen atom, and a transition metal salt. The polyol-containing composition of the present invention contains an ammonium carboxylate salt which is a quaternary ammonium salt of a carboxylic acid having 5 or more carbon atoms, a heterocyclic compound having a nitrogen atom, and a transition metal salt as catalysts, and thereby can achieve both stability of the blowing agent against the catalyst and good foamability.

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

Examples of the polylactone polyol 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.

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.

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, etc. 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, etc.
Examples of hydroxycarboxylic acids include castor oil and reaction products of castor oil and ethylene glycol.

Examples of polymer polyols include polymers obtained by graft-polymerizing ethylenically unsaturated compounds such as acrylonitrile, styrene, methyl acrylate, and methacrylate with aromatic polyols, alicyclic polyols, aliphatic polyols, and polyester polyols, polybutadiene polyols, and modified polyols of polyhydric alcohols or hydrogenated products thereof.

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 (novolaks).

Although the method for modifying the polyhydric alcohol is not particularly limited, a method of adding an alkylene oxide (hereinafter also referred to as "AO") is preferably used. Examples of the 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, from the viewpoints of properties and reactivity, PO, EO and 1,2-butylene oxide are preferred, 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 or random addition, or a combination of these may be used.

Examples of polyether polyols include polymers obtained by ring-opening polymerization of at least one alkylene oxide, such as ethylene oxide, propylene oxide, and 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.

Polyols used in the present invention are preferably polyester polyols and polyether polyols. Also, polyols having two hydroxyl groups are preferred. Among them, from the viewpoint of enhancing flame retardancy, aromatic polyester polyols, which are polyester polyols having aromatic rings, are preferred. More preferred aromatic polyester polyols are those obtained by dehydration condensation of polybasic acids having aromatic rings, such as isophthalic acid (m-phthalic acid) and terephthalic acid (p-phthalic acid), with dihydric alcohols, such as bisphenol A, ethylene glycol, and 1,2-propylene glycol.

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 is likely 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 the strength.
The hydroxyl value of the polyol can be measured in accordance with JIS K 1557-1:2007.

The content of polyol 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. If the content of polyol is equal to or greater than the lower limit, it is preferable because it makes it easier for the polyol and the polyisocyanate to react with each other. On the other hand, if the content of polyol is equal to or less than the upper limit, it is preferable from the viewpoint of handleability because the viscosity of the polyol-containing composition does not become too high.

<Catalyst>
The polyol-containing composition of the present invention uses three types of catalysts in combination: a carboxylate ammonium salt, which is a quaternary ammonium salt of a carboxylic acid having 5 or more carbon atoms, a heterocyclic compound having a nitrogen atom, and a transition metal salt. By using three types of catalysts in combination, the polyol-containing composition of the present invention can suppress the decomposition of the blowing agent by the catalyst and increase the activity of the catalyst to improve the foaming property.

Ammonium carboxylate (trimerization catalyst)
The polyol-containing composition of the present invention contains an ammonium carboxylate. The ammonium carboxylate is a trimerization catalyst and facilitates the formation of an isocyanurate bond through a trimer of a polyisocyanate.
In the present invention, the ammonium carboxylate is a quaternary ammonium salt of a carboxylic acid having 5 or more carbon atoms. The carboxylic acid is preferably an aliphatic carboxylic acid, more preferably a saturated aliphatic carboxylic acid. The number of carbon atoms of the carboxylic acid is, for example, 20 or less, preferably 12 or less, more preferably 8 or less. The carboxylic acid may be linear or may have a branched structure, but preferably has a branched structure. If the carboxylic acid has a branched structure, the reactivity with a blowing agent such as hydrofluoroolefin is likely to be low due to steric hindrance.

The quaternary ammonium ion used in the ammonium carboxylate is preferably a tetraalkylammonium ion, in which each alkyl group has, for example, 1 to 4 carbon atoms, preferably 1 to 2 carbon atoms, and more preferably methyl.
Specific examples of suitable quaternary ammonium ions include tetramethylammonium ion, tetraethylammonium ion, and triethylmethylammonium ion, etc. Among these, trimethylethylammonium ion and tetramethylammonium ion are more preferable, and tetramethylammonium ion is even more preferable.

Among them, the ammonium carboxylate salt is preferably an ammonium carboxylate salt represented by the following general formula (1). The ammonium carboxylate salt represented by the following general formula (1) has a moderate steric hindrance, so that it can suppress the reaction that decomposes the blowing agent and also prevent a decrease in catalytic activity.

(In 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.)

^R1 and ^R2 in the general formula (1) each independently represent 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.
Furthermore, ^R3 represents a hydrogen atom or an alkyl group, and the alkyl group preferably has 1 to 6 carbon atoms. Furthermore, ^R3 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.
When the carbon numbers of R ¹ , R ² and R ³ are equal to or greater than the lower limit, the steric hindrance becomes large, and the reaction of decomposing the hydrofluoroolefin can be suppressed. On the other hand, when the carbon numbers of R ¹ , R ² and R ³ are equal to or less than the upper limit, the steric hindrance does not become too large, and the reactivity can be prevented from slowing down.
M ⁺ represents a quaternary ammonium ion, and details of the quaternary ammonium ion are as described above.

Specific examples of the carboxylic acid in the ammonium carboxylate include at least one selected from 2,2-dimethylpropanoic acid in which R ¹ , R ² , and R ³ are all methyl groups, and 2-ethylhexanoic acid in which R ¹ is an ethyl group, R ² is a butyl group, and R ³ is a hydrogen atom. Among these, 2,2-dimethylpropanoic acid is particularly preferred.
Specific examples of suitable ammonium carboxylates include tetramethylammonium 2,2-dimethylpropanoate and triethylmethylammonium 2-ethylhexanoate. From the viewpoint of facilitating the formation of an isocyanurate bond by a trimer of polyisocyanate, tetramethylammonium 2,2-dimethylpropanoate is more preferred.
In the present invention, the ammonium carboxylates may be used alone or in combination of two or more kinds.

The amount of ammonium carboxylate in the polyol-containing composition is preferably 1 to 28 parts by mass, more preferably 2 to 26 parts by mass, even more preferably 3 to 24 parts by mass, even more preferably 4 to 22 parts by mass, even more preferably 5 to 20 parts by mass, and particularly preferably 6 to 15 parts by mass, per 100 parts by mass of polyol. If the amount of ammonium carboxylate is equal to or greater than the lower limit, trimerization of the polyisocyanate is more likely to occur, improving the flame retardancy of the resulting polyurethane foam. On the other hand, if the amount of ammonium carboxylate is equal to or less than the upper limit, the reaction is easier to control.

<Heterocyclic compounds having 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 polyol and the polyisocyanate are easily reacted with each other.

The heterocyclic compound having a nitrogen atom used in the present invention is not particularly limited, but is preferably a compound containing a nitrogen atom in the heterocycle, more preferably a 4- to 8-membered heterocyclic compound containing a nitrogen atom in the heterocycle, more specifically, imidazole derivatives, pyridine derivatives, piperazine derivatives, etc. Among these, imidazole derivatives are preferred.
The imidazole derivative is an imidazole substituted at the 1- and 2-positions with an alkyl group having 8 or less carbon atoms, and the alkyl group preferably has 6 or less carbon atoms, more preferably has 4 or less carbon atoms. A specific example of a suitable imidazole derivative is represented by the following general formula (2).

(In the general formula (2), R ⁴ and R ⁵ each independently represent an alkyl group having 1 to 8 carbon atoms.)

In the general formula (2), R ⁴ and R ⁵ each independently represent an alkyl group having 1 to 8 carbon atoms, preferably an alkyl group having 1 to 6 carbon atoms, and more preferably an alkyl group having 1 to 4 carbon atoms. If the carbon number of the alkyl group of R ⁴ and R ⁵ is equal to or greater than the lower limit, the steric hindrance becomes large, and the reaction between the polyol and the polyisocyanate is prevented from being affected by a foaming agent such as hydrofluoroolefin. If the carbon number of the alkyl group of R ⁴ and R ⁵ is equal to or less than the upper limit, the steric hindrance does not become extremely large, and the reaction between the polyol and the polyisocyanate can be rapidly promoted. The alkyl groups may each be linear or have a branched structure.
Examples of the imidazole derivative represented by the general formula (2) include 1,2-dimethylimidazole, 1-ethyl-2-methylimidazole, 1-methyl-2-ethylimidazole, 1,2-diethylimidazole, and 1-isobutyl-2-methylimidazole, and among these, 1,2-dimethylimidazole and 1-isobutyl-2-methylimidazole are preferred from the viewpoint of improving the activity of the catalyst in the presence of a hydrofluoroolefin and from the viewpoint of rapidly progressing the reaction. Furthermore, 1,2-dimethylimidazole is even more preferred from the viewpoint of further enhancing stability.

The amount of the heterocyclic compound having a nitrogen atom in the polyol-containing composition is preferably 0.7 to 21 parts by mass, more preferably 0.8 to 19 parts by mass, even more preferably 0.9 to 17 parts by mass, and even more preferably 1.0 to 15 parts by mass, per 100 parts by mass of polyol. If the amount of the heterocyclic compound having a nitrogen atom is equal to or greater than the lower limit, urethane bonds are more likely to be formed and the reaction proceeds quickly. On the other hand, if the amount of the heterocyclic compound having a nitrogen atom is equal to or less than the upper limit, the reaction rate is more easily controlled, which is preferable.

<<Transition metal salt (resinification catalyst)>>
The polyol-containing composition of the present invention contains a transition metal salt as a resinification catalyst. When the polyol-containing composition contains a transition metal salt as a resinification catalyst, the polyol-containing composition is easily reacted with the polyol and the polyisocyanate while suppressing decomposition by a blowing agent and increasing stability.

The transition metal salt used in the present invention is not particularly limited, but examples include metal salts of bismuth, tin, zinc, copper, iron, and lead, among which metal salts of bismuth or tin are preferred, and metal salts of bismuth are more preferred.

The transition metal salt is preferably an organic acid metal salt, more preferably a metal salt of a carboxylic acid having 5 or more carbon atoms. The carboxylic acid has 5 or more carbon atoms, and thus the stability with a blowing agent, particularly with a hydrofluoroolefin, is good. In addition, the carbon number of the carboxylic acid is preferably 18 or less, more preferably 12 or less, from the viewpoint of catalytic activity. The carboxylic acid is preferably an aliphatic carboxylic acid, more preferably a saturated aliphatic carboxylic acid. The carboxylic acid may be linear or may have a branched structure, but preferably has a branched structure.
Specific examples of the carboxylic acid include octylic acid, lauric acid, versatic acid, pentanoic acid, and acetic acid, and among these, octylic acid is preferred. That is, the transition metal salt is preferably a metal salt of octylic acid. These carboxylic acids may be linear as described above, but may also have a branched structure. An example of an octylic acid having a branched structure is 2-ethylhexanoic acid.
As the metal salt of carboxylic acid, bismuth salt of carboxylic acid and tin salt of carboxylic acid are preferable, and among them, bismuth salt of octylic acid is preferable. In addition, the metal salt of carboxylic acid may be a carboxylate of an alkyl metal. For example, the tin salt of carboxylic acid may be a dialkyltin carboxylate, and preferably a dioctyltin carboxylate.
Specific examples of metal salts of carboxylic acids include bismuth trioctate, dioctyltin versatate, dibutyltin dilaurate, dioctyltin dilaurate, tin dioctylate, and lead dioctylate, and preferably bismuth trioctate and dioctyltin versatate, and more preferably bismuth trioctate.

The amount of transition metal salt in the polyol-containing composition is preferably 0.1 to 8 parts by mass, more preferably 0.2 to 7 parts by mass, even more preferably 0.3 to 6 parts by mass, and even more preferably 0.4 to 5 parts by mass, per 100 parts by mass of polyol. If the amount of transition metal salt is equal to or greater than the lower limit, the curing reaction speed of the foamable polyurethane composition can be improved. On the other hand, if the amount of transition metal salt is equal to or less than the upper limit, the reaction can be easily controlled.

<Foaming Agent>
The polyol-containing composition of the present invention preferably contains a hydrofluoroolefin as a blowing agent. In the present invention, even when a hydrofluoroolefin is used as a blowing agent, the blowing agent is highly stable and the catalytic activity is not easily reduced. Examples of the hydrofluoroolefin 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 specifically, examples thereof 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 kinds.

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 above 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 above upper limit, excessive foaming can be suppressed.

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 point 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, 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 handleability, and water is preferred from the viewpoint of adjusting the isocyanate index and ease of handling.

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 prevented.

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

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, it becomes easier to foam the mixture of the polyol-containing composition and the polyisocyanate, 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.

<Flame retardants>
The polyol-containing composition of the present invention may contain a flame retardant. The polyurethane foam produced using the polyol-containing composition of the present invention has excellent flame retardancy because it contains an isocyanurate bond formed by trimerization of polyisocyanate, but 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, a phosphoric acid ester, a phosphate-containing flame retardant, a bromine-containing flame retardant, a boric acid-containing flame retardant, an antimony-containing flame retardant, or a metal hydroxide.

Commercially available red phosphorus can be used as the red phosphorus, but from the standpoint of safety, such as moisture resistance and the prevention of spontaneous combustion during kneading, it is preferable to use red phosphorus particles whose surfaces are coated with a resin.

As the phosphate ester, it is preferable to use monophosphate esters, condensed phosphate esters, etc., 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, monoisodecyl phosphate, 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, resylcinol bis(diphenyl phosphate), bisphenol A bis(diphenyl phosphate), phosphaphenanthrene, and tris(β-chloropropyl)phosphate.

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.

Examples of the phosphate-containing flame retardant include phosphates consisting of salts of various phosphoric acids and at least one metal or compound selected from metals of Groups IA to IVB of the periodic table, ammonia, aliphatic amines, and aromatic amines.
Metals in Groups IA to IVB of the Periodic Table include lithium, sodium, calcium, barium, iron (II), iron (III), aluminum, and the like.
Examples of the aliphatic amine include methylamine, ethylamine, diethylamine, triethylamine, ethylenediamine, and piperazine.
Examples of the aromatic amine include pyridine, triazine, melamine, and ammonium.

Specific examples of phosphate-containing flame retardants include monophosphates and polyphosphates.
The monophosphate salt is not particularly limited, and examples thereof include ammonium salts such as ammonium phosphate, ammonium dihydrogen phosphate, and diammonium hydrogen phosphate; sodium salts such as monosodium phosphate, disodium phosphate, trisodium phosphate, monosodium phosphite, disodium phosphite, and sodium hypophosphite; potassium salts such as monopotassium phosphate, dipotassium phosphate, tripotassium phosphate, monopotassium phosphite, dipotassium phosphite, and potassium hypophosphite; lithium salts such as monolithium phosphate, dilithium phosphate, trilithium phosphate, monolithium phosphite, dilithium phosphite, and lithium hypophosphite; barium salts such as barium dihydrogen phosphate, barium hydrogen phosphate, tribarium phosphate, and barium hypophosphite; magnesium salts such as monohydrogen magnesium phosphate, magnesium hydrogen phosphate, trimagnesium phosphate, and magnesium hypophosphite; calcium salts such as calcium dihydrogen phosphate, calcium hydrogen phosphate, tricalcium phosphate, and calcium hypophosphite; and zinc salts such as zinc phosphate, zinc phosphite, and zinc hypophosphite.
The polyphosphate is not particularly limited, but examples thereof include ammonium polyphosphate, piperazine polyphosphate, melamine polyphosphate, ammonium amide polyphosphate, and aluminum polyphosphate.
The phosphate-containing flame retardants may be used alone or in combination.

The bromine-containing flame retardant is not particularly limited as long as it is a compound containing bromine in its molecular structure, and examples thereof include aromatic brominated compounds.
Specific examples of aromatic brominated compounds include monomeric organic bromine compounds such as hexabromobenzene, pentabromotoluene, hexabromobiphenyl, decabromobiphenyl, hexabromocyclodecane, decabromodiphenyl ether, octabromodiphenyl ether, hexabromodiphenyl ether, bis(pentabromophenoxy)ethane, ethylene-bis(tetrabromophthalimide), and tetrabromobisphenol A; brominated polycarbonates such as polycarbonate oligomers produced using brominated bisphenol A as a raw material, and copolymers of polycarbonate oligomers and bisphenol A; Examples of the brominated epoxy compounds include brominated epoxy compounds such as diepoxy compounds produced by the reaction of brominated bisphenol A with epichlorohydrin and monoepoxy compounds obtained by the reaction of brominated phenols with epichlorohydrin, poly(brominated benzyl acrylate), brominated polyphenylene ether, brominated bisphenol A, condensates of cyanuric chloride and brominated phenol, brominated (polystyrene), poly(brominated styrene), brominated polystyrenes such as crosslinked brominated polystyrene, and crosslinked or non-crosslinked brominated poly(methylstyrene), etc.
The bromine-containing flame retardants may be used singly or in combination.

The boric acid-containing flame retardant is preferably at least one selected from the group consisting of boron oxide, boric acid, and metal borate salts.

Examples of antimony-containing flame retardants include antimony oxide, antimonates, and pyroantimonates.
Examples of antimony oxide include antimony trioxide and antimony pentoxide.
Examples of antimonate include sodium antimonate and potassium antimonate.
Examples of pyroantimonate include sodium pyroantimonate and potassium pyroantimonate.
The antimony-containing flame retardants may be used alone or in combination.

Examples of metal hydroxides include aluminum hydroxide, magnesium hydroxide, calcium hydroxide, iron hydroxide, nickel hydroxide, zirconium hydroxide, zinc hydroxide, titanium hydroxide, copper hydroxide, tin hydroxide, and vanadium hydroxide.
The metal hydroxides may be used alone or in combination of two or more.

When the polyol-containing composition of the present invention contains a flame retardant, the blending amount 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 above lower limit, sufficient flame retardancy can be imparted to the 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 above upper limit, foaming during production of the polyurethane foam is not inhibited.

Among the above-mentioned flame retardants, phosphate esters are preferred from the viewpoints of compatibility with polyol, solubility, etc. As the phosphate ester, monophosphate esters are preferred, and tris(β-chloropropyl)phosphate is more preferred, from the viewpoints of reducing the viscosity of a mixture of a polyol-containing composition and a polyisocyanate to facilitate production, and of improving the flame retardancy of a polyurethane foam.
In the polyol-containing composition, as the flame retardant, a phosphoric acid ester may be used alone, or a phosphoric acid ester may be used in combination with another flame retardant.
The amount of the phosphate ester in the polyol-containing composition is preferably 5 to 100 parts by mass, more preferably 12 to 90 parts by mass, even more preferably 20 to 75 parts by mass, and even more preferably 32 to 65 parts by mass, per 100 parts by mass of the polyol.

<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, but if it does contain one, the amount of 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 polyol.

<Other ingredients>
The polyol-containing composition may contain, as necessary, 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 object of the present invention.

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

[Foamable polyurethane composition and polyurethane foam]
The foamable polyurethane composition of the present invention contains the polyol-containing composition of the present invention and a polyisocyanate, and is obtained by mixing them. The polyurethane foam of the present invention is a reaction product obtained by reacting and foaming the foamable polyurethane composition.

<Polyisocyanate>
Examples of the polyisocyanate 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.

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

Examples of aliphatic polyisocyanates include methylene diisocyanate, ethylene diisocyanate, propylene diisocyanate, tetramethylene diisocyanate, and hexamethylene diisocyanate.

Among these, from the viewpoints of ease of use and availability, aromatic polyisocyanates are preferred, and diphenylmethane diisocyanate is more preferred. The polyisocyanates may be used alone or in combination of two or more.
Furthermore, the polyisocyanate may be appropriately mixed with known additives that are mixed with polyisocyanates before being mixed with the polyol-containing composition.

It is preferable that the polyol-containing composition and the polyisocyanate mixed into the polyol-containing composition 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.

<Isocyanate Index>
The isocyanate index of the polyurethane foam of the present invention is not particularly limited, but is preferably 250 or more. If the isocyanate index is equal to or more than the lower limit, the amount of polyisocyanate relative to the polyol becomes excessive, and isocyanurate bonds due to the trimer of polyisocyanate are easily formed, resulting in improved flame retardancy of the polyurethane foam. In addition, it is also possible to impart non-flammability. Furthermore, if the isocyanate index is equal to or more than the lower limit, it is easy to produce a polyurethane foam having sufficient isocyanurate bonds, that is, a polyurethane foam having both flame retardancy and heat insulation at a high level, in combination with the above-mentioned ammonium carboxylate salt, heterocyclic compound having a nitrogen atom, and transition metal salt. From these viewpoints, the isocyanate index is more preferably 300 or more, even more preferably 350 or more, and even more preferably 400 or more.
The isocyanate index is preferably not more than 1,000, more preferably not more than 800, and even more preferably not more than 600. When the isocyanate index is not more than the above upper limit, the resulting polyurethane foam has a good balance between flame retardancy and production costs.

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

<Method of manufacturing polyurethane foam>
There is no particular limitation on the method for producing the polyurethane foam, but it is preferable to mix a polyisocyanate with a polyol-containing composition to obtain a foamable polyurethane composition, and then foam and react the mixture. Specifically, it is preferable to mix the polyisocyanate with the polyol-containing composition by collision using a spray gun or the like, and spray the mixture.
In the present invention, the foamable polyurethane composition may be obtained by mixing the polyisocyanate and the polyol-containing composition, pouring the mixture into a container such as a mold or a frame, and curing the mixture.

<Applications of polyurethane foam>
The polyurethane foam of the present invention is not particularly limited in its applications, but since it has excellent flame retardancy and heat insulation, it can be suitably used in buildings such as walls, ceilings, roofs, floors, etc. 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 materials of buildings.

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

1. Production of Polyurethane Foams Polyurethane foams according to the examples and comparative examples were prepared in two parts: (1) a polyol-containing composition and (2) a polyisocyanate, according to the formulations shown in Table 1. The details of each component in the table are as follows.

(1) Polyol-containing composition [Polyol]
p-Phthalic acid polyester polyol (manufactured by Kawasaki Chemical Industries, Ltd., product name: Maximol RLK-087, hydroxyl value = 200 mg KOH/g)

[Foam stabilizer]
Silicone foam stabilizer (manufactured by Dow Corning Toray Co., Ltd., product name: SH-193, octamethylcyclotetrasiloxane)

〔catalyst〕
Trimerization catalyst, 2,2-dimethylpropanoic acid tetramethylammonium salt (manufactured by Air Products, product name: DABCO TMR7), concentration approximately 45% by mass
Trimerization catalyst, 2-ethylhexanoic acid triethylmethylammonium salt (manufactured by San-Apro Co., Ltd., product name: U-CAT 18X), concentration approximately 99% by mass
Resinized amine catalyst, 1,2-dimethylimidazole (manufactured by Tosoh Corporation, product name: TOYOCAT (registered trademark)-DM70) concentration 65 to 75% by mass
Resinized amine catalyst, 1-isobutyl-2-methylimidazole (manufactured by Air Products, product name: DABCO NC-IM), concentration approximately 98% by mass
Resinized metal catalyst, bismuth trioctate (manufactured by Nitto Kasei Co., Ltd., product name: Neostan U-600) concentration 55 to 58% by mass
Resinized metal catalyst, dioctyltin versatate (manufactured by Nitto Kasei Co., Ltd., product name: Neostan U-830), concentration approximately 99% by mass
Trimeric amine catalyst, tetramethylammonium acetate salt (manufactured by Tosoh Corporation, product name: TOYOCAT (registered trademark)-TRX) concentration 60 to 70% by mass
Trimerization metal catalyst, potassium 2-ethylhexanoate (manufactured by Air Products, product name: DABCO K-15) concentration 70 to 80% by mass
Resinized amine catalyst, N,N,N',N'',N''-pentamethyldiethylenetriamine (manufactured by Tosoh Corporation, product name: TOYOCAT (registered trademark)-TT), concentration approximately 99% by mass

[Foaming Agent]
Hydrofluoroolefin (manufactured by Honeywell Japan, product name: Soltis LBA, trans-1-chloro-3,3,3-trifluoropropene)
·water

〔Flame retardants〕
Tris(β-chloropropyl)phosphate (manufactured by Daihachi Chemical Industry Co., Ltd., product name: TMCPP)

[Inorganic filler]
Wollastonite ( _SiO2.CaO ) (Kinsei Matec Co., Ltd., product name: SH-1250)

(2) Polyisocyanate 4,4'-diphenylmethane diisocyanate (4,4'-MDI) (manufactured by Manka Chemical Japan Co., Ltd., product name: PM200)

The foamable polyurethane resin composition was formed according to the following procedure.
(1) 200 g of TMCPP was added to 100 g of the kneaded mixture of the components of the polyol-containing composition for dilution (3-fold dilution), and (2) polyisocyanate was added. Then, at an outside temperature of 20° C. and a liquid temperature of 15±1° C., the mixture was stirred for 3 seconds at 8,000 rpm with a hand mixer (PRIMIX Co., Ltd. high-speed disperser Homo Disper 2.5 type) to prepare a foamable polyurethane resin composition. (At this time, 3 times the amount of polyisocyanate was also added for dilution.)

2. Evaluation The Examples and Comparative Examples were evaluated according to the following criteria.
[Foamability]
The gel time of the foamable polyurethane resin composition prepared by the above method was measured. A gel time of less than 10 seconds indicates high reaction activity and poor foaming, while a gel time of more than 16 seconds indicates low reaction activity and poor curing. Therefore, gel times of 12 to 14 seconds were rated as "A", more than 14 to 16 seconds as "B", and less than 10 seconds or more than 16 seconds as "C". The results are shown in Table 1.
The gel time refers to the time from stirring the foamable polyurethane resin composition until the resin starts to form strings around a metal rod when a metal rod is pierced into the foamable polyurethane resin composition during the reaction, or the time until a hole made by piercing a metal rod into the foamable polyurethane resin composition during the reaction is closed.

〔Stability〕
The foamable polyurethane resin composition prepared by the above method was placed in a pressure-resistant container and stored in a thermostatic chamber at 60° C. for 3 days. Thereafter, the gel time was measured in the same manner, and the results were rated as "A" for 20 seconds or less, "B" for more than 20 seconds and 23 seconds or less, and "C" for more than 23 seconds. The results are shown in Table 1.

As is clear from the results of the above examples, by using three types of catalysts in combination: a carboxylic acid ammonium salt, which is a quaternary ammonium salt of a carboxylic acid having 5 or more carbon atoms, a heterocyclic compound having a nitrogen atom, and a transition metal salt, the decomposition of the blowing agent by the catalyst was suppressed, and the stability of the blowing agent against the catalyst was obtained. In other words, the polyol-containing composition of the present invention was able to increase the activity of the catalyst and improve the foaming property.

Claims (7)

A polyol-containing composition for reacting with a polyisocyanate to obtain a polyurethane foam, the composition comprising a polyol, a blowing agent, and a catalyst,
The catalyst contains a carboxylate ammonium salt, which is a quaternary ammonium salt of a carboxylic acid having 5 or more carbon atoms, a heterocyclic compound having a nitrogen atom, and a metal salt of a carboxylic acid having 5 or more carbon atoms ,
the ammonium carboxylate is tetramethylammonium 2,2-dimethylpropanoate,
the heterocyclic compound is an imidazole derivative, and the imidazole derivative is at least one selected from the group consisting of 1,2-dimethylimidazole and 1-isobutyl-2-methylimidazole;
the metal in the metal salt of a carboxylic acid having 5 or more carbon atoms is bismuth,
The polyol-containing composition , wherein the blowing agent comprises a hydrofluoroolefin . The polyol-containing composition of claim 1 , wherein the imidazole derivative is 1,2-dimethylimidazole. The polyol-containing composition according to claim 1 or 2 , wherein the metal salt of a carboxylic acid having 5 or more carbon atoms is a metal salt of octylic acid. The polyol-containing composition according to any one of claims 1 to 3 , further comprising a foam stabilizer. A foamable polyurethane composition comprising the polyol-containing composition according to any one of claims 1 to 4 and a polyisocyanate. 6. The foamable polyurethane composition of claim 5 , having an isocyanate index of 250 or greater. A polyurethane foam obtained by reacting and foaming the foamable polyurethane composition according to claim 5 or 6 .