Polyol, composition, rigid polyurethane foam, method for producing polyol, method for producing rigid polyurethane foam

Abstract

To provide a polyol capable of producing a rigid polyurethane foam having low thermal conductivity, a composition comprising the polyol, a rigid polyurethane foam, a method for producing the polyol and a method for producing the rigid polyurethane foam.SOLUTION: There is provided a polyol which comprises a residue obtained by removing an active hydrogen from an aromatic amine having two or more active hydrogens which is an initiator and an oxyalkylene chain comprising an ethylene oxide-based unit and a propylene oxide-based unit bonded to the residue, wherein the oxyalkylene chain has, from the residue side, a block chain comprising an ethylene oxide-based unit, a block chain comprising a propylene oxide-based unit and a random chain comprising an ethylene oxide-based unit and a propylene oxide-based unit in this order.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a polyol, a composition, a rigid polyurethane foam, a method for producing a polyol, and a method for producing a rigid polyurethane foam.

Background Art

[0002] Rigid polyurethane foam is produced by reacting a polyol compound and a polyisocyanate compound in the presence of a blowing agent or the like. The bubbles in the rigid polyurethane foam are roughly classified into two types: closed cells and open cells. Open cells are connected to each other, and a rigid polyurethane foam having many open cells has excellent dimensional stability and is used as a heat insulating material for civil engineering applications, construction, and building materials.

[0003] On the other hand, a rigid polyurethane foam having many open cells has a problem that the heat conductivity increases (that is, the heat insulating performance decreases) because gas exchange easily occurs between the gas in the cells and the outside air (generally air) present in the environmental atmosphere. Patent Document 1 discloses a method for producing a rigid polyurethane foam by reacting a polyisocyanate and a compound having at least two hydrogen atoms that react with an isocyanate group in the presence of a blowing agent. Patent Document 1 describes that the compound having at least two hydrogen atoms that react with the isocyanate group contains at least one polyether alcohol, and the polyether alcohol can be produced by reacting an aromatic amine with ethylene oxide and propylene oxide. In the reaction, in the first treatment stage, first propylene oxide, and then ethylene oxide or a mixture of ethylene oxide and propylene oxide, and in the second treatment stage, the remaining amount of propylene oxide is added under the use of a basic catalyst. And it is disclosed that the rigid polyurethane foam obtained by the said method has low heat conductivity.

Prior Art Documents

Patent Documents

[0004] Patent Document 1 Japanese Patent Application Laid-Open No. 2010-509477 Summary of the Invention Problems to be Solved by the Invention

[0005] However, the heat insulation performance of the rigid polyurethane foam produced by the method described in Patent Document 1 is not sufficient. An object of the present invention is to provide a polyol capable of producing a rigid polyurethane foam having a low thermal conductivity, a composition containing the polyol, a rigid polyurethane foam produced from the polyol, a method for producing the polyol, and a method for producing the rigid polyurethane foam. Means for Solving the Problems

[0006] The present invention is as follows [1] to

[16] . [1] A polyol comprising a residue obtained by removing active hydrogen from an aromatic amine having two or more active hydrogens as an initiator, and an oxyalkylene chain composed of units based on ethylene oxide and units based on propylene oxide bonded to the residue, wherein the oxyalkylene chain is (i) or (ii). (i) An oxyalkylene chain having, in this order, a block chain composed of units based on ethylene oxide, a block chain composed of units based on propylene oxide, and a random chain composed of units based on ethylene oxide and units based on propylene oxide, starting from the residue side. (ii) An oxyalkylene chain having, in this order, a block chain composed of units based on propylene oxide, a block chain composed of units based on ethylene oxide, and a random chain composed of units based on ethylene oxide and units based on propylene oxide, starting from the residue side. [2] The polyol according to [1], wherein the oxyalkylene chain is the oxyalkylene chain of (i). [3] The polyol according to [1] or [2], represented by the following Formula 1. Xa -[(EO) a1 -(PO) a2 -(EO a3 / PO a4 )-H] a5 Formula 1 In the above Formula 1, X a is the residue obtained by removing active hydrogen from the initiator, (EO) a1 is a block chain composed of units based on ethylene oxide, a1 is the average number of units based on ethylene oxide in the block chain composed of units based on ethylene oxide in the polyol represented by the above Formula 1, a1 is 0.1 to 1.0, (PO) a2 is a block chain composed of units based on propylene oxide, a2 is the average number of units based on propylene oxide in the block chain composed of units based on propylene oxide in the polyol represented by the above Formula 1, a2 is 0.5 to 2.5, EO a3 / PO a4 is a random chain composed of units based on ethylene oxide and units based on propylene oxide, a3 is the average number of units based on ethylene oxide in the random chain composed of units based on ethylene oxide and units based on propylene oxide in the polyol represented by the above Formula 1, a3 is 0.5 to 2.0, a4 is the average number of units based on propylene oxide in the random chain composed of units based on ethylene oxide and units based on propylene oxide in the polyol represented by the above Formula 1, a4 is 0.1 to 1.0, and a5 is an integer of 2 or more. [4] The polyol according to any one of [1] to [3], wherein in the oxyalkylene chain, the content of units based on ethylene oxide in the random chain relative to the total mass of the random chain is more than 20% by mass. [5] The polyol according to any one of [1] to [4], wherein the content of units based on ethylene oxide relative to the total mass of the polyol is 10 to 50% by mass. [6] The polyol according to any one of [1] to [5], having a hydroxyl value of 125 to 250 mgKOH / g. [7] The aromatic amine-containing polyol according to any one of [1] to [6] contains toluenediamine. [8] The aromatic amine-containing polyol according to any one of [1] to [7] contains either or both of 2,4-toluenediamine and 2,6-toluenediamine, and the content of 2,4-toluenediamine and 2,6-toluenediamine relative to the total mass of the aromatic amine is 95% by mass or more.

[0007] [9] A composition containing a polyol and a blowing agent, wherein the polyol according to [1] to [8] is contained in an amount of 30% by mass or more based on the total mass of the polyol, and the blowing agent contains only water.

[10] The composition according to [9], which is for producing rigid polyurethane foam.

[0008]

[11] A rigid polyurethane foam which is a foamed cured product obtained by reacting the composition according to [9] or

[10] with a polyisocyanate.

[12] The rigid polyurethane foam according to

[11] , wherein the average cell diameter of the cells of the rigid polyurethane foam is 130 to 200 μm.

[0009]

[13] A method for producing a polyol having an oxyalkylene chain of (i) according to any one of [1] to [8], comprising forming a block chain composed of units based on ethylene oxide by subjecting ethylene oxide to ring-opening addition polymerization to an initiator, forming a block chain composed of units based on propylene oxide by subjecting propylene oxide to ring-opening addition polymerization to the hydroxyl group at the end of the block chain composed of units based on ethylene oxide, and forming a random chain composed of units based on ethylene oxide and units based on propylene oxide by subjecting a mixture of ethylene oxide and propylene oxide to ring-opening addition polymerization to the hydroxyl group at the end of the block chain composed of units based on propylene oxide.

[14] The method for producing a polyol according to

[13] , wherein the ring-opening addition polymerization of ethylene oxide is carried out in the absence of a ring-opening polymerization catalyst.

[15] The ring-opening addition polymerization of the propylene oxide is carried out in the presence of a ring-opening polymerization catalyst, and is a method for producing a polyol as described in

[13] or

[14] .

[0010]

[16] A method for producing a rigid polyurethane foam, which includes reacting the composition described in [9] or

[10] with a polyisocyanate. [Effects of the Invention]

[0011] According to the present invention, it is possible to provide a polyol capable of producing a rigid polyurethane foam having a low thermal conductivity, a composition containing the polyol, a rigid polyurethane foam produced from the polyol, a method for producing the polyol, and a method for producing the rigid polyurethane foam. [Modes for Carrying Out the Invention]

[0012] The meanings and definitions of the terms in this specification are as follows. A numerical range represented by "~" means a numerical range having the numerical values before and after ~ as the lower limit value and the upper limit value, respectively. The "unit" constituting the polyol means an atomic group directly formed by ring-opening addition polymerization of an alkylene oxide. The "active hydrogen" means a hydrogen atom of a reactive group to which an alkylene oxide can undergo ring-opening addition, and means a hydrogen atom bonded to an oxygen atom, a nitrogen atom, a sulfur atom, etc. Also, water is regarded as having active hydrogen.

[0013] The "hydroxyl value" of the polyol is a value measured in accordance with Method B (phthalation method) described in JIS K 1557-1:2007. The molecular weight in terms of hydroxyl value is a value calculated by 56100 × the number of functional groups (number of hydroxyl groups) of the polyol / hydroxyl value. The "density (core density)" of the rigid polyurethane foam is a value measured in accordance with JIS K 7222:2005. The thermal conductivity of the rigid polyurethane foam is a value measured in accordance with JIS A 1412:2016.

[0014] ≪Polyol≫ The polyol of this embodiment (hereinafter also referred to as "polyol P1") is composed of a residue obtained by removing active hydrogen from an aromatic amine having two or more active hydrogens as an initiator, and units based on ethylene oxide (hereinafter also referred to as "EO units") and units based on propylene oxide (hereinafter also referred to as "PO units") bonded to the residue. The oxyalkylene chain consists of an oxyalkylene chain. The oxyalkylene chain is as follows: (i) or (ii). (i) An oxyalkylene chain having, in this order, a block chain composed of units based on ethylene oxide, a block chain composed of units based on propylene oxide, and a random chain composed of units based on ethylene oxide and units based on propylene oxide, starting from the residue side. (ii) An oxyalkylene chain having, in this order, a block chain composed of units based on propylene oxide, a block chain composed of units based on ethylene oxide, and a random chain composed of units based on ethylene oxide and units based on propylene oxide, starting from the residue side.

[0015] Hereinafter, the oxyalkylene chain of (i) is also referred to as "oxyalkylene chain A", and the oxyalkylene chain of (ii) is also referred to as "oxyalkylene chain B". Also, the polyol P1 having the oxyalkylene chain A is also referred to as "polyol P1A". The polyol P1 having the oxyalkylene chain B is also referred to as "polyol P1B".

[0016] The hydroxyl value of the polyol P1 is preferably 125 to 250 mgKOH / g, more preferably 150 to 250 mgKOH / g, still more preferably 200 to 250 mgKOH / g, and particularly preferably 210 to 240 mgKOH / g. When the hydroxyl value is at least the lower limit value, the hardness of the resulting rigid polyurethane foam tends to be high. When the hydroxyl value is at most the upper limit value, the storage stability of the composition containing the polyol P1 tends to be improved.

[0017] The hydroxyl value-converted molecular weight of polyol P1 is preferably from 900 to 1,800, more preferably from 900 to 1,500, and even more preferably from 900 to 1,100. When the hydroxyl value-converted molecular weight is at least the lower limit value, for example, when using a polyol having a large hydroxyl value-converted molecular weight in combination, the compatibility with the polyol is likely to be improved. When the hydroxyl value-converted molecular weight is at most the upper limit value, the storage stability of the composition containing polyol P1 is likely to be improved. The hydroxyl value-converted molecular weight per monofunctional group of polyol P1 is preferably from 225 to 450, more preferably from 225 to 375, and even more preferably from 225 to 275. When the Mw per monofunctional group is at least the lower limit value, for example, when using a polyol having a large hydroxyl value-converted molecular weight in combination, the compatibility with the polyol is likely to be improved. When the hydroxyl value-converted molecular weight per monofunctional group is at most the upper limit value, the storage stability of the composition containing polyol P1 is likely to be improved.

[0018] The total content of EO units relative to the total mass of polyol P1 is preferably from 10 to 50% by mass, more preferably from 15 to 40% by mass, and even more preferably from 20 to 35% by mass. When the total content of EO units is within the above range, polyol P1 has an excellent balance of hydrophilicity and hydrophobicity, and the storage stability of the composition containing polyol P1 is likely to be improved.

[0019] The total content of PO units relative to the total mass of polyol P1 is preferably from 35 to 65% by mass, more preferably from 40 to 50% by mass, and even more preferably from 45 to 55% by mass. When the total content of PO units is within the above range, polyol P1 has an excellent balance of hydrophilicity and hydrophobicity, and the storage stability of the composition containing polyol P1 is likely to be improved.

[0020] The content of the residue obtained by removing active hydrogen from the initiator relative to the total mass of polyol P1 is preferably from 10 to 40% by mass, more preferably from 10 to 30% by mass, and even more preferably from 10 to 20% by mass. When within the above range, the viscosity of the polyol is likely to be low.

[0021] The content of the block chain composed of PO units (hereinafter also referred to as "PO block chain") with respect to the total mass of PO units and EO units in polyol P1 is preferably 25 to 60% by mass, more preferably 30 to 55% by mass, and even more preferably 35 to 55% by mass. When the content of the PO block chain is within the above range, polyol P1 has an excellent balance between hydrophilicity and hydrophobicity, and the storage stability of the composition containing polyol P1 is likely to be improved.

[0022] The content of the block chain composed of EO units (hereinafter also referred to as "EO block chain") with respect to the total mass of PO units and EO units in polyol P1 is preferably 5 to 25% by mass, more preferably 7 to 20% by mass, and even more preferably 10 to 20% by mass. When the content of the EO block chain is not less than the above lower limit value, the viscosity of polyol P1 is likely to decrease. When the content of the EO block chain is not more than the above upper limit value, the crystallinity of polyol P1 is likely to decrease.

[0023] The content of the random chain composed of EO units and PO units (hereinafter also referred to as "EO / PO random chain") with respect to the total mass of PO units and EO units in polyol P1 is preferably 15 to 50% by mass, more preferably 20 to 50% by mass, and even more preferably 25 to 45% by mass. When the content of the EO / PO random chain is within the above range, polyol P1 has an excellent balance between hydrophilicity and hydrophobicity, and the storage stability of the composition containing polyol P1 is likely to be improved.

[0024] The content of EO units with respect to the total mass of PO units and EO units in the EO / PO random chain is preferably more than 20% by mass, more preferably 40 to 95% by mass, and even more preferably 60 to 90% by mass. When the content of EO units is within the above range, polyol P1 has an excellent balance between hydrophilicity and hydrophobicity, the storage stability of the composition containing polyol P1 is likely to be improved, and the effect of maintaining small particle sizes of foam cells, which is presumed to be derived from surface activity performance, is likely to be obtained.

[0025] The number of functional groups (hydroxyl groups) of the polyol P1 is 2 or more, preferably 2 to 8, more preferably 2 to 6, and even more preferably 2 to 4. The number of functional groups (hydroxyl groups) of the polyol P1 is the same as the number of active hydrogens of the aromatic amine that is the initiator.

[0026] As the aromatic amine, an aromatic amine having an amino group bonded to an aromatic ring is preferred. The active hydrogen is preferably the active hydrogen derived from the amino group. Examples of the aromatic amine include 2,4-toluenediamine, 2,6-toluenediamine, aniline, 4-methyl-1,3-phenylenediamine, 2-methyl-1,3-phenylenediamine, 4,4'-diphenylmethanediamine, and Mannich reaction products. The Mannich reaction product is a reaction product of phenols, alkanolamines, and aldehydes. For example, a reaction product of nonylphenol, monoethanolamine, and formaldehyde is exemplified. Among them, toluenediamine is preferred, and 2,4-toluenediamine and 2,6-toluenediamine are more preferred. The aromatic amine may be one kind or a mixture of two or more kinds may be used. When the aromatic amine contains either one or both of 2,4-toluenediamine and 2,6-toluenediamine, the total content of 2,4-toluenediamine and 2,6-toluenediamine with respect to the total mass of the aromatic amine is preferably 95% by mass or more, more preferably 97% by mass or more, and may be 100% by mass.

[0027] The advantages of using the aromatic amine as an initiator are as follows. First, since the initiator has an aromatic ring, the heat insulation property of the obtained rigid polyurethane foam is likely to be improved. Second, when an aromatic polyisocyanate such as MDI is used in urethanization, the miscibility with the polyisocyanate is likely to be improved. Third, since the amine moiety can also function as a catalyst for urethanization, the urethanization reaction is likely to be promoted.

[0028] As the polyol P1A, a polyol represented by the following formula 1 is preferred.

[0029] X a -[(EO) a1 -(PO) a2 -(EO a3 / PO a4 )-H] a5 Formula 1 In Formula 1 above, X a is the residue obtained by removing the active hydrogen from the initiator, (EO) a1 is a block chain composed of EO units, a1 is the average number of EO units of the block chain composed of EO units in the polyol represented by Formula 1 above, a1 is 0.1 to 1.0, (PO) a2 is a block chain composed of PO units, a2 is the average number of PO units of the block chain composed of PO units in the polyol represented by Formula 1 above, a2 is 0.5 to 2.5, EO a3 / PO a4 is a random chain composed of EO units and PO units, a3 is the average number of EO units of the random chain composed of EO units and PO units in the polyol represented by Formula 1 above, a3 is 0.5 to 2.0, a4 is the average number of PO units of the random chain composed of EO units and PO units in the polyol represented by Formula 1 above, a4 is 0.1 to 1.0, and a5 is an integer of 2 or more.

[0030] a1 is preferably 0.2 to 0.9, more preferably 0.3 to 0.8, and even more preferably 0.4 to 0.7. a2 is preferably 0.7 to 2.3, more preferably 0.8 to 2.2, and even more preferably 1.0 to 2.1. a3 is preferably 0.8 to 1.8, more preferably 1.0 to 1.7, and even more preferably 1.1 to 1.6. a4 is preferably 0.15 to 0.9, more preferably 0.2 to 0.8, and even more preferably 0.25 to 0.7. a5 is 2 or more, preferably 2 to 8, more preferably 2 to 6, even more preferably 2 to 4, still more preferably 3 to 4, and particularly preferably 4.

[0031] (a1 + a2) / (a3 + a4) is preferably from 0.6 to 2.0, more preferably from 0.8 to 1.7. a1 / (a3 + a4) is preferably from 0.1 to 0.6, more preferably from 0.2 to 0.5. a2 / (a3 + a4) is preferably from 0.5 to 1.5, more preferably from 0.6 to 1.4. a1 / a2 is preferably from 0.1 to 1.3, more preferably from 0.2 to 0.5.

[0032] As the polyol P1B, a polyol represented by the following formula 2 is preferred.

[0033] X b -[(PO) b1 -(EO) b2 -(EO b3 / PO b4 )-H] b5 Formula 2 In the above formula 2, X b is the residue obtained by removing the active hydrogen from the initiator, (PO) b1 is a block chain composed of PO units, b1 is the average number of PO units of the block chain composed of PO units in the polyol represented by the formula 2, b1 is from 0.5 to 2.5, (EO) b2 is a block chain composed of EO units, b2 is the average number of EO units of the block chain composed of EO units in the polyol represented by the formula 2, b2 is from 0.1 to 1.0, EO b3 / PO b4 is a random chain composed of EO units and PO units, b3 is the average number of EO units of the random chain composed of EO units and PO units in the polyol represented by the formula 2, b3 is from 0.5 to 2.0, b4 is the average number of PO units of the random chain composed of EO units and PO units in the polyol represented by the formula 2, b4 is from 0.1 to 1.0, and b5 is an integer of 2 or more.

[0034] b1 is preferably from 0.7 to 2.3, more preferably from 0.8 to 2.2, and even more preferably from 1.0 to 2.1. b2 is preferably from 0.2 to 0.9, more preferably from 0.3 to 0.8, and even more preferably from 0.4 to 0.7. b3 is preferably from 0.8 to 1.8, more preferably from 1.0 to 1.7, and even more preferably from 1.1 to 1.6. b4 is preferably from 0.15 to 0.9, more preferably from 0.2 to 0.8, and even more preferably from 0.25 to 0.7. b5 is 2 or more, preferably from 2 to 8, more preferably from 2 to 6, even more preferably from 2 to 4, still even more preferably from 3 to 4, and particularly preferably 4.

[0035] (b1 + b2) / (b3 + b4) is preferably from 0.6 to 2.0, and more preferably from 0.8 to 1.7. b1 / (b3 + b4) is preferably from 0.5 to 1.5, and more preferably from 0.6 to 1.4. b2 / (b3 + b4) is preferably from 0.1 to 0.6, and more preferably from 0.2 to 0.5. b1 / b2 is preferably from 0.1 to 1.3, and more preferably from 0.2 to 0.5.

[0036] As the polyol P1, polyol P1A is preferred, and polyol P1A represented by the above formula 1 is more preferred. Polyol P1A is more likely to have a lower viscosity than polyol P1B. Therefore, compared with polyol P1B, the blending amount of polyol P1A in the composition can be increased, and the storage stability of the composition is likely to be good.

[0037] ≪Manufacturing method of polyol P1A and polyol P1B≫ The method for producing the polyol P1A of the present embodiment includes a first step of forming a block chain composed of the EO units by subjecting an aromatic amine having two or more active hydrogens as an initiator to ring-opening addition polymerization of ethylene oxide, a second step of forming a block chain composed of the PO units by subjecting the hydroxyl group at the terminal of the block chain composed of the EO units to ring-opening addition polymerization of propylene oxide, and a third step of forming a random chain composed of the EO units and the PO units by subjecting the hydroxyl group at the terminal of the block chain composed of the PO units to ring-opening addition polymerization of a mixture of ethylene oxide and propylene oxide. The method for producing the polyol P1B of the present embodiment can be carried out in the same manner as the method for producing the polyol P1A described above, except that in the first step, propylene oxide is subjected to ring-opening addition polymerization and in the second step, ethylene oxide is subjected to ring-opening addition polymerization.

[0038] The ring-opening addition polymerization of ethylene oxide, the ring-opening addition polymerization of propylene oxide, and the ring-opening addition polymerization of a mixture of ethylene oxide and propylene oxide may be carried out in the presence of a ring-opening polymerization catalyst.

[0039] Examples of the ring-opening polymerization catalyst include a double metal cyanide complex catalyst, a Lewis acid catalyst, and an alkali metal catalyst, and an alkali metal catalyst is preferred. The ring-opening polymerization catalyst may be one type or a mixture of two or more types, but one type is preferred. As the double metal cyanide complex catalyst, a double metal cyanide complex catalyst in which an organic ligand is coordinated to zinc hexacyanocobaltate is preferred. Examples of the organic ligand include tert-butanol, tert-pentyl alcohol, ethylene glycol mono-tert-butyl ether, and a combination of tert-butanol and ethylene glycol mono-tert-butyl ether. Examples of the Lewis acid catalyst include BF3 complex, tris(pentafluorophenyl)borane, and tris(pentafluorophenyl)aluminum. Examples of the alkali metal catalyst include alkali metal compounds such as cesium hydroxide, potassium hydroxide, and sodium hydroxide, and potassium hydroxide is preferred.

[0040] In the method for producing polyol P1A and the method for producing polyol P1B, the first step is preferably carried out in the absence of a catalyst, the second step is preferably carried out in the presence of a catalyst, and the third step is preferably carried out in the presence of a catalyst. When an alkali metal catalyst is used, it reacts with a hydroxyl group to generate water. Therefore, in the reaction system, a polyol produced by ring-opening addition polymerization of either ethylene oxide or propylene oxide to this water may be generated.

[0041] <<Composition>> The composition of this embodiment contains a polyol and a blowing agent. The polyol may consist only of polyol P1, or may be a polyol mixture containing polyol P1 and a polyol other than polyol P1. As the polyol other than polyol P1, either one or both of polyol P2 and polyol P3 described later may be used. In addition to the polyol and the blowing agent, the composition may contain a flame retardant, a foam stabilizer, and a urethanization catalyst. The composition may contain other compounding agents in addition to the flame retardant, the foam stabilizer, and the urethanization catalyst. The composition of this embodiment can be used as a polyol system liquid for producing rigid polyurethane foam.

[0042] <Polyol> The polyol may be a polyol mixture composed of polyol P1 and polyols P2 and P3 other than polyol P1.

[0043] (Polyol P2) Polyol P2 is a polyol obtained by subjecting an initiator having 2 to 8 active hydrogens to ring-opening addition polymerization of an alkylene oxide. The hydroxyl value-converted molecular weight per functional group of polyol P2 is 1,000 to 2,000, and the content of EO units with respect to the total mass of polyol P2 is 15% by mass or less. Polyol P2 can function as a foam breaker.

[0044] The functionality number of the polyol P2 is from 2 to 8, preferably from 2 to 6, more preferably from 2 to 3. The functionality number of the polyol P2 is consistent with the number of active hydrogens possessed by the initiator.

[0045] The hydroxyl value-converted molecular weight of the polyol P2 is preferably from 2,000 to 6,000, more preferably from 3,000 to 5,000, and even more preferably from 3,000 to 4,000. When the hydroxyl value-converted molecular weight is at least the lower limit value, the function as a defoaming agent can be easily obtained. When the hydroxyl value-converted molecular weight is at most the upper limit value, the storage stability of the composition is likely to be improved. The hydroxyl value-converted molecular weight per functional group of the polyol P2 is from 1,000 to 2,000, more preferably from 1,000 to 1,700, and even more preferably from 1,000 to 1,500. When the hydroxyl value-converted molecular weight per functional group is at least the lower limit value, the function as a defoaming agent can be easily obtained. When the hydroxyl value-converted molecular weight per functional group is at most the upper limit value, the storage stability of the composition is likely to be improved.

[0046] The hydroxyl value of the polyol P2 is preferably from 28 to 84 mgKOH / g, more preferably from 34 to 56 mgKOH / g, and even more preferably from 42 to 56 mgKOH / g. When the hydroxyl value is at least the lower limit value, the storage stability of the composition is likely to be improved. When the hydroxyl value is at most the upper limit value, the function as a defoaming agent can be easily obtained.

[0047] Examples of the alkylene oxide include ethylene oxide, propylene oxide, 1,2-epoxybutane, 2,3-epoxybutane, and styrene oxide. Propylene oxide and ethylene oxide are preferred, and propylene oxide is preferred.

[0048] When the polyol P2 contains PO units, the content of PO units relative to the total mass of alkylene oxide units in the polyol P2 is preferably 85% by mass or more, more preferably 90% by mass or more, and may be 100% by mass. When the content of PO units is at least the lower limit value, the function as a defoaming agent can be easily obtained.

[0049] When the polyol P2 contains EO units and PO units, the total content of the EO units and the PO units relative to the total mass of the alkylene oxide units in the polyol P2 is preferably 80% by mass or more, more preferably 90% by mass or more, and may be 100% by mass.

[0050] When the polyol P2 contains EO units and PO units, the content of the EO units relative to the total mass of the alkylene oxide units in the polyol P2 is preferably 0 to 15% by mass, more preferably 0 to 10% by mass, and even more preferably 0 to 5% by mass. When the content of the EO units is at least the lower limit value, the storage stability of the composition is likely to be improved. When the content of the EO units is at most the upper limit value, the function as a defoaming agent is likely to be obtained.

[0051] The polyol P2 may have a block chain composed of one type of alkylene oxide unit, or may have a random chain composed of two or more types of alkylene oxide units.

[0052] The initiator of the polyol P2 is not particularly limited as long as it has 2 to 8 active hydrogens. Examples of the initiator of the polyol P2 include an initiator containing no nitrogen atom and an initiator containing a nitrogen atom. The initiator may be one type, or two or more types may be used in combination.

[0053] As the initiator containing no nitrogen atom, water and polyhydric alcohols are preferable. Examples of the polyhydric alcohols include ethylene glycol, propylene glycol, glycerin, trimethylolpropane, diethylene glycol, diglycerin, pentaerythritol, sorbitol, and sucrose. Water, ethylene glycol, propylene glycol, glycerin, trimethylolpropane, diglycerin, pentaerythritol, sorbitol, and sucrose are preferable.

[0054] Examples of the initiator containing a nitrogen atom include amine compounds. As the amine compound, an amine compound having at least one nitrogen atom to which a hydrogen atom is bonded or an amine compound having a hydroxyl group (which may have a nitrogen atom to which a hydrogen atom is bonded) is preferable. Examples of such amine compounds include aliphatic amines, alicyclic amines, and aromatic amines having a nitrogen atom to which a hydrogen atom or a hydroxyalkyl group is bonded. Examples of the aliphatic amines include alkylamines such as ethylenediamine, hexamethylenediamine, and diethylenetriamine, and alkanolamines such as monoethanolamine, diethanolamine, and triethanolamine. Examples of the alicyclic amines include aminoethylpiperazine. Examples of the aromatic amines include the aromatic amines described for the polyol P1. Among them, polyhydric alcohols are preferable in terms of high defoaming property and low viscosity.

[0055] (Polyol P3) Polyol P3 is a polyol obtained by subjecting an initiator having 2 to 8 active hydrogens to ring-opening addition polymerization of an alkylene oxide. The molecular weight in terms of hydroxyl value per functional group of polyol P3 is 20 to 500. Polyol P3 has a function of adjusting the physical properties of polyol P. For example, it is used to reduce the viscosity (decrease in viscosity) of the composition and to adjust the aromatic ring content and crosslinking degree in polyol P. By using polyol P1, the storage stability of the composition is improved, and since polyol P1 has an aromatic ring derived from the initiator, polyol P3 is not essential in the composition of the present invention.

[0056] The number of functional groups of polyol P3 is 2 to 8, preferably 2 to 6, and more preferably 2 to 4. The number of functional groups of polyol P3 coincides with the number of active hydrogens possessed by the initiator.

[0057] The hydroxyl value converted molecular weight of polyol P3 is preferably from 50 to 1,000, more preferably from 80 to 900, and even more preferably from 100 to 800. When the hydroxyl value converted molecular weight is at least the lower limit value, the effect of adjusting the aromatic ring content and the degree of crosslinking is high, and when the hydroxyl value converted molecular weight is at most the upper limit value, the viscosity reduction effect is easily obtained. The hydroxyl value converted molecular weight per functional group of polyol P3 is preferably from 20 to 500, more preferably from 30 to 400, and even more preferably from 50 to 300. When the hydroxyl value converted molecular weight per functional group is at least the lower limit value, the effect of adjusting the aromatic ring content and the degree of crosslinking is high, and when the hydroxyl value converted molecular weight per functional group is at most the upper limit value, the viscosity reduction effect is easily obtained.

[0058] The hydroxyl value of polyol P3 is preferably from 200 to 900 mgKOH / g, more preferably from 250 to 900 mgKOH / g, and even more preferably from 300 to 900 mgKOH / g. When the hydroxyl value is at least the lower limit value, the effect of adjusting the aromatic ring content and the degree of crosslinking is high, and when the hydroxyl value is at most the upper limit value, the viscosity reduction effect is easily obtained.

[0059] Examples of the alkylene oxide include ethylene oxide (EO), propylene oxide (PO), 1,2-epoxybutane, 2,3-epoxybutane, and styrene oxide, and propylene oxide and ethylene oxide are preferred.

[0060] When polyol P3 contains EO units, the content of EO units relative to the total mass of alkylene oxide units in polyol P3 is preferably from 10 to 100% by mass, more preferably from 10 to 90% by mass, and even more preferably from 20 to 80% by mass.

[0061] When polyol P3 contains PO units, the content of PO units relative to the total mass of alkylene oxide units in polyol P3 is preferably from 10 to 100% by mass, more preferably from 10 to 90% by mass, and even more preferably from 20 to 80% by mass.

[0062] When the polyol P3 contains EO units and PO units, the total content of the EO units and PO units relative to the total mass of the alkylene oxide units in the polyol P3 is preferably 80% by mass or more, more preferably 90% by mass or more, and may be 100% by mass.

[0063] The polyol P3 may have a block chain composed of one type of alkylene oxide unit, or may have a random chain composed of two or more types of alkylene oxide units.

[0064] The initiator of the polyol P3 is not particularly limited as long as it has 2 to 8 active hydrogens. Examples of the initiator of the polyol P3 include the initiators exemplified for the above-mentioned polyol P2.

[0065] In addition to the polyols P1, P2, and P3, the polyol may contain a compound having an active hydrogen capable of reacting with an isocyanate group (active hydrogen compound). Examples of the compound having an active hydrogen include a compound having a hydroxyl group, a compound having an amino group, and a compound having both a hydroxyl and an amino group. Examples of the active hydrogen compound include polyols not included in any of the polyols P1 to P3, polyhydric alcohols not included in any of the polyols P1 to P3, polyhydric phenols, and polyether polyamines.

[0066] Examples of the polyols include polyether polyols, polyester polyols, polycarbonate polyols, and the like. Examples of polyhydric phenols include non-condensed compounds such as bisphenol A and resorcinol, resole-type initial condensates obtained by condensing and bonding phenols with excessive aldehydes in the presence of an alkali catalyst, benzylic-type initial condensates obtained by reacting non-aqueous systems during the synthesis of the resole-type initial condensates, novolak-type initial condensates obtained by reacting excessive phenols with aldehydes in the presence of an acid catalyst, and the like. The molecular weight of these initial condensates is preferably about 200 to 10,000. In the above, examples of phenols include phenol, cresol, bisphenol A, resorcinol, and the like. Examples of aldehydes include formalin, paraformaldehyde, and the like. Polyether polyamines are compounds obtained by converting the hydroxyl groups of polyether polyols into amino groups or amino group-containing organic groups. For example, polyether triamine (manufactured by Texaco, trade name: Jeffamine T-5000) having a number average molecular weight of 5,000 and an amination rate of 95% obtained by subjecting glycerin to ring-opening addition of propylene oxide and then aminating its hydroxyl group can be mentioned.

[0067] The content of polyol P1 relative to the total mass of the polyol is preferably 30% by mass or more, more preferably 40% by mass or more, and still more preferably 50% by mass or more. When the content of polyol P1 is at least the above lower limit value, the storage stability of the composition is likely to be improved. In addition, since a large amount of aromatic ring-containing polyol is contained, the thermal conductivity is likely to be improved.

[0068] When the polyol contains polyol P2, the content of polyol P2 relative to the total mass of the polyol is preferably 10 to 40% by mass, more preferably 15 to 30% by mass, and still more preferably 20 to 25% by mass. When the content of polyol P2 is at least the above lower limit value, it is easy to obtain the function as a defoaming agent. When the content of polyol P2 is at most the above upper limit value, the storage stability of the composition is likely to be improved.

[0069] The content of polyol P3 relative to the total mass of the polyol is preferably 0 to 50% by mass, more preferably 10 to 30% by mass, and even more preferably 10 to 20% by mass.

[0070] The content of the active hydrogen compound relative to the total mass of the polyol is preferably 0 to 30% by mass, more preferably 0 to 20% by mass, and even more preferably 0 to 10% by mass.

[0071] When the polyol contains polyol P2, the ratio of the content of polyol P1 to the content of polyol P2 is preferably 0.5 to 5, more preferably 1 to 4, and even more preferably 1.5 to 3.

[0072] The content of the polyol relative to the total mass of the composition is preferably 40 to 60% by mass, more preferably 50 to 60% by mass, and even more preferably 55 to 60% by mass.

[0073] (Blowing agent) The composition of this embodiment contains a blowing agent. Examples of the blowing agent include water. Other blowing agents can be appropriately selected from known blowing agents, such as HFCs such as CF2H2, CF3CF2H, CF3CH3, CHF2CF2H, CF3CH2F, CHF2CH3, CF3CHFCF3, CF3CF2CHFCHFCF3, CHF2CH2CF3, CH3CF2CH2CF3, HCs such as cyclopentane, HCFCs such as CCl2FCH3, HFEs such as CF3CF2CF2OCH3, CHF2CF2OCH3, HCFOs other than 1224yd such as CF3CH = CClH, HFOs other than 1336mzz, and chlorine-based blowing agents such as CHCl = CClH, CH2Cl2. When the composition contains other blowing agents as the blowing agent, the ratio of the other blowing agents is preferably 50% by mass or less, more preferably 10% by mass or less, based on the total mass of the blowing agent. When it is below the above upper limit value, the physical properties of the obtained rigid polyurethane foam are less likely to be impaired. It is particularly preferred that the blowing agent contains only water. The amount of the blowing agent used is preferably 5 to 25 parts by mass, more preferably 6 to 20 parts by mass, and still more preferably 7 to 18 parts by mass with respect to 100 parts by mass of the total amount of the polyol. When the amount of the blowing agent used is at least the lower limit value, the rigid polyurethane foam is likely to be lightweight. When the amount of the blowing agent used is at most the upper limit value, the miscibility of the blowing agent and the polyol composition P is likely to be improved.

[0074] (Flame retardant) Examples of the flame retardant include phosphorus-based flame retardants, and tricresyl phosphate, triethyl phosphate, tris(β-chloroethyl) phosphate, and tris(β-chloropropyl) phosphate are preferable. The amount of the flame retardant used is preferably 10 to 100 parts by mass, more preferably 30 to 80 parts by mass, and still more preferably 40 to 70 parts by mass with respect to 100 parts by mass of the total amount of the polyol. When the amount of the flame retardant used is at least the lower limit value, the flame retardancy of the rigid polyurethane foam is likely to be improved. When the amount of the flame retardant used is at most the upper limit value, the storage stability of the composition is likely to be improved. The flame retardant may be one kind, or two or more kinds may be mixed and used.

[0075] (Foam stabilizer) Examples of the foam stabilizer include silicone-based foam stabilizers and fluorine-containing compound-based foam stabilizers. Generally, in addition to the silicone-based foam stabilizers used in the production of rigid polyurethane foams, silicone-based foam stabilizers used in the production of highly breathable flexible urethane foams may also be used. The amount of the foam stabilizer used may be appropriately selected, but is preferably 0.1 to 10 parts by mass with respect to 100 parts by mass of the total amount of the polyol.

[0076] (Urethanization catalyst) Examples of urethanization catalysts include amine catalysts such as N,N,N’,N”,N”-pentamethyldiethylenetriamine, bis(2-dimethylaminoethyl) ether, triethylenediamine, and N,N,N’,N’-tetramethylhexamethylenediamine; reactive amine catalysts such as N,N,N’-trimethylaminoethylethanolamine; and organometallic catalysts such as dibutyltin dilaurate. A catalyst that promotes the trimerization reaction of the isocyanate group may also be used in combination, and examples include metal carboxylates such as potassium acetate and potassium 2-ethylhexanoate. The amount of the urethanization catalyst used is preferably 0.1 to 30 parts by mass with respect to 100 parts by mass of the polyol P. The amount of the catalyst that promotes the trimerization reaction used is preferably 0.1 to 30 parts by mass with respect to 100 parts by mass of the total amount of the polyol. As the urethanization catalyst, it is preferable to use an amine catalyst or a reactive amine catalyst.

[0077] (Other compounding agents) Examples of other compounding agents include fillers such as calcium carbonate and barium sulfate; anti-aging agents such as antioxidants and ultraviolet absorbers; plasticizers, colorants, fungicides, defoaming agents, dispersants, and discoloration inhibitors.

[0078] ≪Rigid polyurethane foam and method for producing rigid polyurethane foam≫ The rigid polyurethane foam of the present embodiment is a foamed and cured product obtained by reacting the above composition with a polyisocyanate.

[0079] The density (core density) of the rigid polyurethane foam is preferably 10 to 30 kg / m 3 and more preferably 12 to 25 kg / m 3 and even more preferably 13 to 23 kg / m 3 When the density is within the above range, the rigid urethane foam is excellent in economy.

[0080] The thermal conductivity of the rigid polyurethane foam is preferably from 0.030 to 0.036 W / (m·K), more preferably from 0.031 to 0.035 W / (m·K), and even more preferably from 0.032 to 0.034 W / (m·K). When the thermal conductivity of the rigid polyurethane foam is below the above upper limit value, the heat insulation performance is improved.

[0081] The average diameter (average cell diameter) of the cells of the rigid polyurethane foam measured by the method described in the examples below is preferably from 130 to 200 μm, more preferably from 140 to 180 μm, and even more preferably from 150 to 170 μm. When the average cell diameter is below the above upper limit value, the thermal conductivity of the rigid polyurethane foam tends to be low.

[0082] (Polyisocyanate) Polyisocyanate is a compound having two or more isocyanate groups. Examples of polyisocyanates include aromatic, alicyclic, aliphatic polyisocyanates; mixtures of two or more of the above polyisocyanates; and modified polyisocyanates obtained by modifying these. Specific examples include tolylene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), polymethylene polyphenyl polyisocyanate (commonly known as crude MDI), xylylene diisocyanate (XDI), isophorone diisocyanate (IPDI), hexamethylene diisocyanate (HDI) and other polyisocyanates or their prepolymer type modified products, allophanate modified products, urea modified products, carbodiimide modified products, etc. Among these, TDI, MDI, crude MDI or their modified products are preferred. Crude MDI is particularly preferred in terms of ease of availability and ease of handling. The polyisocyanate may be used alone or in a mixture of two or more.

[0083] The amount of polyisocyanate used, in terms of the isocyanate index, is preferably from 40 to 150, more preferably from 50 to 120, and even more preferably from 60 to 110. The isocyanate index is the NCO / OH molar ratio represented by the following formula 3. Isocyanate index = Total NCO amount (mol) in polyisocyanate / Total OH amount (mol) of all polyols contained in the composition × 100, Formula 3

[0084] In the method for producing the rigid polyurethane foam of the present embodiment, the mixing method of the composition and the polyisocyanate is not particularly limited, but it is preferably mixed by a spraying method.

[0085] The spraying method refers to a method in which the composition and the polyisocyanate (or a composition containing polyisocyanate, the same applies hereinafter) are each made into fine droplets and ejected from a nozzle, and both droplets are sprayed onto a substrate while being mixed in the air, or a method in which the composition and the polyisocyanate are mixed in a mixing head and the liquid mixture is immediately ejected as droplets from the nozzle of the mixing head and sprayed onto the substrate. It refers to a method of forming a liquid mixture of the composition and the polyisocyanate on a substrate. The liquid mixture of the composition and the polyisocyanate formed on the substrate reacts rapidly to foam and reacts and cures to form a rigid polyurethane foam. Although various methods are known as the spraying method, in the spraying method in the present embodiment, a so-called airless spraying method in which the composition and the polyisocyanate are mixed and sprayed in a mixing head is preferable.

[0086] The spraying method is a method of directly producing a rigid polyurethane foam at a construction site, and has advantages such as being able to suppress construction costs and being able to be constructed without gaps even on a construction surface with unevenness of the base material. Therefore, it is often adopted when forming a heat insulation layer made of rigid polyurethane foam on construction surfaces such as walls, ceilings, foundation parts, and underfloors of buildings such as detached houses, condominiums, office buildings, and prefabricated cold storage warehouses. In addition, a rigid polyurethane foam can be formed in advance on building materials before constructing a building by the spraying method, and the building can be constructed using building materials with a previously formed rigid polyurethane foam layer. Further, the polyurethane foam produced by the present invention is not limited to use as a heat insulating material for buildings and building materials. The polyurethane foam of the present invention is easily lightweight and particularly preferable for building and building material applications.

[0087] According to the present invention, a rigid polyurethane foam having closed cells can be produced by a spraying method using only water as a blowing agent. Despite using only water as a blowing agent, good storage stability of the composition is obtained, and the resulting rigid polyurethane foam has high heat insulation performance.

[0088] <Mechanism of action> The thermal conductivity of a rigid polyurethane foam is considered to be determined as the sum of radiation, conduction in a solid, and conduction in a gas. As described above, the rigid polyurethane foam of the present invention has a small average cell diameter (average cell size). It is considered that the heat conduction by radiation is suppressed due to the small average cell diameter. In addition, in order to keep the average cell diameter of the rigid polyurethane foam small, it is necessary to suppress the coalescence of cells. In the polyol P1 of the present invention, it is considered that the coalescence of cells of the resulting rigid polyurethane foam is suppressed by having a random chain composed of EO units and PO units. Although it is also conceivable to directly bond a random chain composed of EO units and PO units to the residue of the initiator, in this case, it is difficult to obtain a uniform random chain due to the difference in reactivity of ethylene oxide and propylene oxide with respect to the amine. As a result, it is considered that it is difficult to suppress the coalescence of cells of the resulting rigid polyurethane foam, the average cell diameter increases, and it is difficult to obtain the effect of suppressing heat conduction by radiation.

Examples

[0089] The present invention will be described in more detail below using examples, but the present invention is not limited to these examples.

[0090] <Measurement method> [Hydroxyl value) The hydroxyl value of the polyol was measured in accordance with Method B (phthalation method) described in JIS K 1557-1:2007.

[0091] [Molecular weight in terms of hydroxyl value] The molecular weight in terms of hydroxyl value was calculated from 56100 × the number of functional groups (hydroxyl groups) of the polyol / hydroxyl value.

[0092] <Evaluation method> [Storage stability of polyol system liquid] The polyol system liquids obtained in Examples 1 to 5 described below were stored at 20 °C and 40 °C for 1 month. If any one of separation, precipitation, and solidification occurred within 1 week, it was evaluated as ×; if none of them occurred within 1 week and any one of them occurred within 1 month, it was evaluated as △; if none of them occurred for 1 month, it was evaluated as 〇.

[0093] [Evaluation by box-free foam] (Reactive cream time, reactive rise time) 30 g of the polyol system liquid obtained in Examples 1 to 5 described below adjusted to 5 °C and 34.8 g of a polyisocyanate compound (Millionate MR-200: crude MDI, viscosity: 200 mPa·s, NCO content: 31.0 mass% (manufactured by Tosoh Corporation)) adjusted to 5 °C were put into a 500 cm 3 cup, and a foaming stock solution composition was prepared by stirring and mixing at 3,000 rpm for 2 seconds using a stirring device equipped with a stirring blade on a ball mill manufactured by Hitachi. The prepared foaming stock solution composition was quickly put into an upper-open container with a length of 150 mm × width of 150 mm × height of 150 mm to produce a box-free foam (hereinafter, also referred to as "Foam 1"). As an evaluation of reactivity, with the time when the mixing of the polyol system liquid and the polyisocyanate compound started as zero seconds, the time from when the change in hue started until foaming started was measured as the reaction cream time (unit: seconds). Also, with the time when mixing started as zero seconds, the time until the rise of the foam due to foaming stopped was visually measured as the reaction rise time (unit: seconds).

[0094] (Density) A cube with a side length of 100 mm was cut out from the core part of Foam 1, and the density was measured in accordance with JIS K 7222:2005.

[0095] [Evaluation by bun-shaped form] After adjusting to 5°C, 130 g of the polyol system liquid obtained in Examples 1 to 5 described below and 150.8 g of the polyisocyanate compound adjusted to 5°C (Millionate MR-200: crude MDI, viscosity: 200 mPa·s, NCO content: 31.0% by mass (manufactured by Tosoh Corporation)) were put into a 500 cm 3 cup, stirred at 3,000 rpm for 2 seconds with a stirring device equipped with a stirring blade on a ball mill manufactured by Hitachi, Ltd. to cause foaming, and then put into a mold with a size of 400 mm in length and width, 50 mm in height, and an open top to produce a bun-shaped form (hereinafter, also referred to as "Form 2"). The isocyanate index is shown in Table 2. Using Form 2, shrinkage, average cell diameter, and thermal conductivity were evaluated.

[0096] (Shrinkage) In the production of Form 2, after the rise of Form 2 due to foaming stopped, it was left at 23°C for 30 minutes, and the external appearance state was observed. Those without deformation were marked as ○. In addition, when the polyols of Examples 1 to 5 described below were used, all of them were marked as ○.

[0097] (Average cell diameter) Form 2 was cut parallel to the height direction from the core part, and the cross section (that is, from the direction perpendicular to the height direction) was observed with a scanning electron microscope (JCM-7000 desktop scanning electron microscope, manufactured by JEOL Ltd.). Twenty randomly selected bubbles (cells) were observed at a magnification of 30 times, the major axis and minor axis of the cells were calculated, and the average value was taken as one cell diameter. The arithmetic mean of the above 20 cell diameters was calculated as the average cell diameter.

[0098] (Thermal conductivity) The thermal conductivity of Form 2 was measured in accordance with JIS A 1412:2016 using a thermal conductivity measuring device (product name: Autolambda HC-074 type, manufactured by Eihong Seiki Co., Ltd.). Specifically, using a sample cut out from the core part of Form 2 with a length and width of 200 mm and a height of 25 mm, the thermal conductivity was measured under the measurement conditions of a high-temperature plate of 38°C, a low-temperature plate of 10°C, and an average temperature of 23°C.

[0099] [Production Example 1] Into a 10 L reactor equipped with a stirrer, stirring blades, a heating jacket, a cooling coil, a nitrogen introduction pipe, and a pressure reduction pipe, 975 g of toluenediamine (a mixture of 80% by mass of 2,4-diaminotoluene and 20% by mass of 2,6-diaminotoluene, purity 99.1%), which is an initiator, was charged. After purging with nitrogen gas, the temperature was raised to 125°C, and after setting the pressure in the tank to 0.01 MPaG, 808 g of ethylene oxide was supplied over 2.3 hours to carry out the reaction. Then, the ethylene oxide remaining in the reactor was reacted at 125°C over 1 hour. Then, after setting the pressure in the tank to 0.01 MPaG, 12.6 g (0.15 part by mass with respect to 100 parts by mass of the finally produced polyol) of 95% by mass potassium hydroxide flakes (manufactured by Toagosei Co., Ltd.) was added as a ring-opening polymerization catalyst, and the nitrogen replacement in the reactor was carried out. After stirring at 125°C for 0.5 hour, 2,898 g of propylene oxide was supplied at 125°C over 4.2 hours to carry out the reaction. Then, the propylene oxide remaining in the reactor was reacted at 125°C over 1 hour until the pressure in the tank became constant. Then, 1,326 g of propylene oxide and 1,992 g of ethylene oxide were mixed in the supply pipe and supplied as a mixed solution over 4.7 hours to carry out the reaction. Then, aging was carried out at 125°C for 1 hour until the pressure in the tank became constant to react the ethylene oxide and propylene oxide remaining in the reactor. Then, the pressure in the reactor was reduced to -0.1 MPaG, and after confirming that there was no unreacted ethylene oxide and propylene oxide, the temperature in the reactor was lowered to 100°C, and 12.9 g of acetic acid (manufactured by Junsei Chemical Co., Ltd.) was added to obtain polyol P1A(1). Polyol P1A(1) is a polyol having an oxyalkylene chain A using toluenediamine as an initiator. The molecular weight in terms of hydroxyl value, a1 to a5 in the above formula 1, hydroxyl value, the EO unit content with respect to the total mass of polyol P1A(1), and the mass ratio of PO unit / EO unit in the random chain composed of EO unit and PO unit are shown in Table 1 (hereinafter, other polyols are shown in the same manner).

[0100] [Production Example 2] Into a 10 L reactor equipped with a stirrer, stirring blades, a heating jacket, a cooling coil, a nitrogen introduction pipe, and a pressure reduction pipe, 975 g of toluenediamine (a mixture of 80% by mass of 2,4-diaminotoluene and 20% by mass of 2,6-diaminotoluene, purity 99.1%), which is an initiator, was charged. After replacement with nitrogen gas, the temperature was raised to 125°C, and after the pressure in the tank was set to 0.01 MPaG, 808 g of ethylene oxide was supplied over 2.3 hours to carry out the reaction. Thereafter, the ethylene oxide remaining in the reactor was reacted at 125°C over 1 hour. Thereafter, after the pressure in the tank was set to 0.01 MPaG, 12.6 g (0.15 part by mass with respect to 100 parts by mass of the finally produced polyol) of 95% by mass potassium hydroxide flakes (manufactured by Toagosei Co., Ltd.) as a ring-opening polymerization catalyst was added, and nitrogen replacement in the reactor was carried out. After stirring at 125°C for 0.5 hour, 3,727 g of propylene oxide was supplied at 125°C over 5.5 hours to carry out the reaction. Thereafter, the propylene oxide remaining in the reactor was reacted at 125°C over 1 hour until the pressure in the tank became constant. Thereafter, 498 g of propylene oxide and 1,992 g of ethylene oxide were mixed in the supply pipe and supplied as a mixed solution over 3.5 hours to carry out the reaction. Thereafter, the ethylene oxide and propylene oxide remaining in the reactor were reacted at 125°C over 1 hour until the pressure in the tank became constant. Thereafter, the inside of the reactor was depressurized to -0.1 MPaG, and after confirming that there was no unreacted ethylene oxide and propylene oxide, the temperature inside the reactor was lowered to 100°C, and 12.9 g of acetic acid (manufactured by Junsei Chemical Co., Ltd.) was added to obtain polyol P1A(2). Polyol P1A(2) is a polyol having the oxyalkylene chain A using toluenediamine as an initiator.

[0101] [Examples 1 to 5] Examples 1 to 4 are examples, and Example 5 is a comparative example. With the formulation shown in Table 2, a blowing agent, a flame retardant, a foam stabilizer, and a urethanization catalyst were added to and mixed with polyol (total: 100 parts by mass) to produce a composition (polyol system liquid). The amounts of the respective components in the polyol system liquid of Table 2 mean parts by mass. The storage stability of the obtained polyol system liquid was evaluated. The results are shown in Table 2. Also, Foam 1 and Foam 2 were produced by the above-described method, and the reactive clean time, reactive rise time, shrinkage, density, shrinkage, average cell diameter, and thermal conductivity were evaluated. The results are shown in Table 2.

[0102] The polyol, blowing agent, flame retardant, foam stabilizer, and urethanization catalyst described in Table 2 are as follows. Polyol P1’: A polyol having a hydroxyl value of 200 mgKOH / g obtained by reacting aminoethylpiperazine (functional group number 3) as an initiator with ethylene oxide and propylene oxide in this order. That is, polyol P1’ is a polyol in which a block chain composed of EO units and a block chain composed of PO units are bonded in this order to the residue of an initiator that is not an aromatic amine. Polyol P2: A polyol having a hydroxyl value of 56 mgKOH / g obtained by reacting glycerin (functional group number 3) as an initiator with propylene oxide. That is, polyol P2 is a polyol in which a block chain composed of PO units is bonded to the residue of the initiator. Polyol P3A: A polyol having a hydroxyl value of 350 mgKOH / g obtained by reacting toluenediamine (functional group number 4) as an initiator with ethylene oxide, propylene oxide, and ethylene oxide in this order. That is, polyol P3A is a polyol in which a block chain composed of EO units, a block chain composed of PO units, and a block chain composed of EO units are bonded in this order to the residue of an initiator composed of an aromatic amine. Polyol P3B: Dipropylene glycol. Also contributes as a viscosity reducer. Blowing agent: Water. Flame retardant: Tris(β-chloropropyl) phosphate (trade name: TMCPP, manufactured by Daihachi Chemical Co., Ltd.). Cell stabilizer: silicone-based cell stabilizer (product name: VORASURF SF2938 Additive, manufactured by Dow Corning Toray Co., Ltd.). Urethane-forming catalyst 1: amine-based reactive catalyst (product name: TOYOCAT-RX5, manufactured by Tosoh Corporation). Urethane-forming catalyst 2: 70% by mass solution of bis(dimethylaminoethyl) ether (30% by mass of dipropylene glycol) (product name: TOYOCAT-ET, manufactured by Tosoh Corporation).

[0103]

Table 1

[0104]

Table 2

[0105] In Examples 1 to 4 using the polyol P1 of the present invention, compared with Example 5, the thermal conductivity of the rigid polyurethane foam was lower and the heat insulation performance was higher. It was considered that Examples 1 to 4 had a smaller average cell diameter of the rigid polyurethane foam than Example 5, which contributed to the decrease in thermal conductivity. Also, in Examples 1 to 4 in which polyol P1 was contained in polyol P, the storage stability of the polyol system liquid was higher than that in Example 5 in which polyol P1 was not contained in polyol P.

Claims

1. It consists of a residue obtained by removing active hydrogen from an aromatic amine having two or more active hydrogens as an initiator, and an oxyalkylene chain composed of units based on ethylene oxide and units based on propylene oxide bonded to the residue, and the oxyalkylene chain is (i) or (ii), a polyol. (i) An oxyalkylene chain having, in this order, a block chain composed of units based on ethylene oxide, a block chain composed of units based on propylene oxide, and a random chain composed of units based on ethylene oxide and units based on propylene oxide, starting from the residue side. (ii) An oxyalkylene chain having, in this order, a block chain composed of units based on propylene oxide, a block chain composed of units based on ethylene oxide, and a random chain composed of units based on ethylene oxide and units based on propylene oxide, starting from the residue side.

2. The polyol according to claim 1, wherein the oxyalkylene chain is the oxyalkylene chain of (i).

3. The polyol according to claim 1, represented by the following formula 1. X ａ - [(EO) ａ１ - (PO) ａ２ - (EO ａ３ / PO ａ４ ) - H] ａ５ Formula 1 In the formula 1, X ａ is the residue obtained by removing active hydrogen from the initiator, (EO) ａ１ is a block chain composed of units based on ethylene oxide, a1 is the average number of units based on ethylene oxide in the block chain composed of units based on ethylene oxide in the polyol represented by the formula 1, a1 is 0.1 to 1.0, (PO) ａ２ is a block chain composed of units based on propylene oxide, a2 is the average number of units based on propylene oxide in the block chain composed of units based on propylene oxide in the polyol represented by the formula 1, a2 is 0.5 to 2.5, EO ａ３ / PO ａ４ is a random chain composed of units based on ethylene oxide and units based on propylene oxide, a3 is the average number of units based on ethylene oxide in the random chain composed of units based on ethylene oxide and units based on propylene oxide in the polyol represented by the above formula 1, a3 is 0.5 to 2.0, a4 is the average number of units based on propylene oxide in the random chain composed of units based on ethylene oxide and units based on propylene oxide in the polyol represented by the above formula 1, a4 is 0.1 to 1.0, and a5 is an integer of 2 or more.

4. In the oxyalkylene chain, the content of the units based on ethylene oxide in the random chain relative to the total mass of the random chain is more than 20% by mass. The polyol according to claim 1.

5. The content of the units based on ethylene oxide relative to the total mass of the polyol is 10 to 50% by mass. The polyol according to claim 1.

6. The polyol according to claim 1, having a hydroxyl value of 125 to 250 mg KOH / g.

7. The polyol according to claim 1, wherein the aromatic amine contains toluenediamine.

8. The aromatic amine contains either one or both of 2,4-toluenediamine and 2,6-toluenediamine, and the content of 2,4-toluenediamine and 2,6-toluenediamine relative to the total mass of the aromatic amine is 95% by mass or more. The polyol according to claim 7.

9. A composition containing a polyol and a blowing agent, containing 30% by mass or more of the polyol according to any one of claims 1 to 8 based on the total mass of the polyol, A composition containing only water as the blowing agent.

10. The composition according to claim 9, which is for producing rigid polyurethane foam.

11. A rigid polyurethane foam which is a foamed cured product obtained by reacting the composition according to claim 9 with a polyisocyanate.

12. The rigid polyurethane foam according to claim 11, wherein the average cell diameter of the cells of the rigid polyurethane foam is 130 to 200 μm.

13. A method for producing a polyol having the oxyalkylene chain of (i) according to any one of claims 1 to 8, By subjecting ethylene oxide to ring-opening addition polymerization to the initiator, a block chain composed of units based on the ethylene oxide is formed, By subjecting propylene oxide to ring-opening addition polymerization to the hydroxyl group at the terminal of the block chain composed of units based on the ethylene oxide, a block chain composed of units based on the propylene oxide is formed, A method for producing a polyol, comprising forming a random chain composed of units based on the ethylene oxide and units based on the propylene oxide by subjecting a mixture of ethylene oxide and propylene oxide to ring-opening addition polymerization to the hydroxyl group at the terminal of the block chain composed of units based on the propylene oxide.

14. The method for producing a polyol according to claim 13, wherein the ring-opening addition polymerization of the ethylene oxide is carried out in the absence of a ring-opening polymerization catalyst.

15. The method for producing a polyol according to claim 13, wherein the ring-opening addition polymerization of the propylene oxide is carried out in the presence of a ring-opening polymerization catalyst.

16. A method for producing a rigid polyurethane foam, comprising reacting the composition according to claim 9 with a polyisocyanate.

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