Foam-forming composition, polyurea-based resin foam, and method for producing polyurea-based resin foam

Abstract

This foamed-resin-formable composition is for obtaining a polyurea-based resin foam body, and contains a reactant (A) between a cyclic polyamine compound (a1) and carbon dioxide, a polyisocyanate compound (B), and an aromatic polyamine compound (C). This polyurea-based resin foam body is obtained by foaming and molding the foamed-resin-formable composition. This polyurea-based resin foam body production method comprises a step for foaming and molding the foamed-resin-formable composition. According to the present invention, it is possible to obtain a polyurea-based resin foam body which can reduce environmental load and which has improved foaming ability.

Description

[Technical field]

[0001] The present invention relates to a resin foam-forming composition, a polyurea resin foam, and a method for producing a polyurea resin foam. [Background technology]

[0002] Polyurea resins are resin compounds having urea bonds that are produced by a chemical reaction between polyisocyanate and polyamine. They are excellent in waterproofness, chemical resistance, abrasion resistance, heat resistance, corrosion resistance, quick-drying properties, environmental safety, and the like, and are widely used in various fields, for example, synthetic leather, artificial leather, adhesives, paints, and the like. Also, studies are being conducted on the foaming of polyurea-based resins to impart functions such as heat insulation, sound insulation, and lightweight properties to the polyurea-based resins. Techniques relating to polyurea-based resin foams include those described in Patent Documents 1 and 2, for example.

[0003] Patent Document 1 describes that a polyurea foam having an isocyanurate structure and an isocyanurate ratio of 25 to 50% has excellent flame retardancy and shape retention during combustion, can suppress deterioration over time in a moist and hot environment, has excellent adhesion to an adherend when applied, is less likely to crack even when exposed to flame, and is less likely to carbonize from the surface to the depths when exposed to flame.

[0004] Patent Document 2 describes that a composition containing an isocyanate component; an isocyanate-reactive component; a catalyst selected from a blowing catalyst and / or a gelling catalyst and containing N-(3-dimethylaminopropyl)-N,N-diisopropanolamine; and a specific amine component, in which the total amount of the amine components is 0.05% by weight to 0.50% by weight, can produce a polyurea foam with reduced formaldehyde emission. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent No. 6925554 [Patent Document 2] JP 2019-206712 A Summary of the Invention [Problem to be solved by the invention]

[0006] Conventionally, a foaming agent was required to obtain a foam, and a large amount of foam had to be used and discarded in order to obtain higher foamability. On the other hand, polyamines used as raw materials for polyurea resins can absorb carbon dioxide, and are therefore useful as materials for absorbing discarded carbon dioxide. The present invention provides a resin foam-forming composition capable of reducing the environmental load and providing a polyurea-based resin foam with improved foamability, a polyurea-based resin foam with improved foamability, and a method for producing the same. [Means for solving the problem]

[0007] The present inventors have conducted extensive research to solve the above problems. As a result, they have found that by using a reaction product of a cyclic amine compound and carbon dioxide and an aromatic amine as raw materials for obtaining a polyurea-based resin foam, the amount of a conventional blowing agent that places a large burden on the environment can be reduced, the environmental burden during the production of the polyurea-based resin foam can be reduced, and the foamability of the obtained polyurea-based resin foam can be improved, thereby completing the present invention. In addition, the reaction product can be produced by absorbing carbon dioxide in the environment, which also contributes to reducing the environmental burden.

[0008] That is, according to the present invention, there are provided a resin foam-forming composition, a polyurea resin foam, and a method for producing a polyurea resin foam, which are shown below.

[0009] [1] A foam-forming composition for obtaining a polyurea-based resin foam, comprising: a reaction product (A) of a cyclic polyamine compound (a1) with carbon dioxide; a polyisocyanate compound (B); and an aromatic polyamine compound (C). [2] The foamable resin-forming composition according to the above [1], wherein the molar ratio ((A) / (C)) of the reaction product (A) of the cyclic polyamine compound (a1) and carbon dioxide to the aromatic polyamine compound (C) in the foamable resin-forming composition is 3 / 7 to 8 / 2. [3] The resin foam-forming composition according to the above [1] or [2], wherein the aromatic polyamine compound (C) has an amine value of 50 to 600 mgKOH / g. [4] The resin foam-forming composition according to any one of the above [1] to [3], which is a resin foam-forming composition for obtaining a polyurea-based resin foam containing a polyurea having a repeating unit represented by the following general formula (I): [ka] (In formula (I), R 1 represents a divalent hydrocarbon group having a cyclic structure which may be substituted, and a divalent organic group having an aromatic ring structure which may be substituted, R 2 is a divalent hydrocarbon group which may have a substituent. In addition, in the divalent organic group having an aromatic ring structure, the aromatic ring is bonded to a nitrogen atom. [5] The resin foam-forming composition according to any one of the above [1] to [4], wherein the polyisocyanate compound (B) contains a compound having two or more isocyanate groups. [6] The resin foam-forming composition according to any one of the above [1] to [5], wherein the cyclic polyamine compound (a1) has an amino group bonded to a primary carbon atom. [7] The resin foam-forming composition according to any one of the above [1] to [6], wherein the cyclic structure of the cyclic polyamine compound (a1) includes at least one selected from the group consisting of a 5-membered ring and a 6-membered ring. [8] The resin foam-forming composition according to any one of the above [1] to [7], wherein the cyclic polyamine compound (a1) has 2 or more and 6 or less amino groups. [9] The resin foam-forming composition according to any one of the above [1] to [8], wherein the cyclic polyamine compound (a1) comprises at least one selected from the group consisting of xylylenediamine and derivatives thereof, bis(aminomethyl)cyclohexane and derivatives thereof, limonenediamine and derivatives thereof, and isophoronediamine and derivatives thereof.

[10] The foamable resin forming composition according to any one of the above [1] to [9], wherein the content of a foaming agent other than the reaction product (A) of the cyclic polyamine compound (a1) and carbon dioxide is 5 mass% or less.

[11] The foamable resin-forming composition according to any one of the items [1] to

[10] , wherein the ratio of the total number of amino groups of the reaction product (A) of the cyclic polyamine compound (a1) and carbon dioxide and the aromatic polyamine compound (C) to the number of isocyanate groups of the polyisocyanate compound (B) in the foamable resin-forming composition (the number of amino groups / the number of isocyanate groups) is 0.5 or more and 1.5 or less.

[12] The resin foam-forming composition according to any one of the above [1] to

[11] , wherein the aromatic polyamine compound (C) is a compound represented by the following formula (III): [ka] (In formula (III), X is a divalent organic group which is at least one of an alkylene group which may have a substituent, a polyoxyalkylene group which may have a substituent, an ether bond, an ester bond, an amide bond, and a single bond, or an organic group which is a combination of these.)

[13] The resin foam-forming composition according to any one of the above [1] to

[12] , wherein the aromatic polyamine compound (C) is a compound represented by the following formula (IIIa): [ka] (In formula (IIIa), n is preferably 1 to 20.)

[14] A polyurea resin foam obtained by foam molding the resin foam-forming composition according to any one of the above [1] to

[13] .

[15] The polyurea resin foam according to

[14] above, which contains a polyurea having a repeating unit represented by the following general formula (I): [ka] (In formula (I), R 1 represents a divalent hydrocarbon group having a cyclic structure which may be substituted, and a divalent organic group having an aromatic ring structure which may be substituted, R 2 is a divalent hydrocarbon group which may have a substituent. In addition, in the divalent organic group having an aromatic ring structure, the aromatic ring is bonded to a nitrogen atom.

[16] The polyurea resin foam according to the above

[14] or

[15] , wherein the aromatic polyamine compound (C) has an amine value of 50 to 600 mgKOH / g.

[17] A method for producing a polyurea resin foam, comprising a step of foam-molding the resin foam-forming composition according to any one of the above [1] to

[13] .

[18] A method for producing the polyurea resin foam according to

[17] above, comprising: a step of contacting a cyclic polyamine compound (a1) with a gas containing carbon dioxide to obtain a reactant (A); and a step of mixing the reactant (A) obtained with a polyisocyanate compound (B) and an aromatic polyamine compound (C) to obtain a foamable resin composition.

[19] The method for producing a polyurea resin foam according to the above

[17] or

[18] , wherein the aromatic polyamine compound (C) has an amine value of 50 to 600 mgKOH / g. Effect of the Invention

[0010] Effects of the Invention According to the present invention, it is possible to provide a resin foam-forming composition which can reduce the environmental load and give a polyurea-based resin foam with improved foamability, a polyurea-based resin foam with improved foamability, and a method for producing the same. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] A mode for carrying out the present invention (hereinafter simply referred to as "the present embodiment") will be described in detail. The present embodiment is an example for explaining the present invention, and does not limit the contents of the present invention. The present invention can be carried out with appropriate modifications within the scope of the gist. In the present embodiment, the provisions considered to be preferable can be adopted arbitrarily, and it can be said that a combination of preferable provisions is more preferable. In the present embodiment, the description "XX to YY" means "XX or more and YY or less."

[0012] [Foam-forming resin composition] The foam-forming composition of the present invention is a foam-forming composition for obtaining a polyurea-based resin foam, and contains a reaction product (A) of a cyclic polyamine compound (a1) with carbon dioxide, a polyisocyanate compound (B), and an aromatic polyamine compound (C). The resin foam-forming composition of the present invention, having the above-mentioned configuration, can reduce the environmental load and give a polyurea resin foam with improved foamability. The term "foamable resin composition" refers to a composition for obtaining a foamed resin or a foam made of a foamed resin, and is a composition that serves as a raw material for a foamed resin or a foam made of a foamed resin.

[0013] The foam-forming composition of the present invention is a foam-forming composition for obtaining a polyurea-based resin foam, and is preferably a foam-forming composition for obtaining a polyurea-based resin foam containing a polyurea having a repeating unit represented by the following general formula (I). [ka] (In formula (I), R 1 represents a divalent hydrocarbon group having a cyclic structure which may be substituted, and a divalent organic group having an aromatic ring structure which may be substituted, R 2 is a divalent hydrocarbon group which may have a substituent. In addition, in the divalent organic group having an aromatic ring structure, the aromatic ring is bonded to a nitrogen atom.

[0014] R 1 includes both a divalent hydrocarbon group having a cyclic structure which may have a substituent and a divalent organic group having an aromatic ring structure which may have a substituent. The divalent hydrocarbon group is derived from a cyclic polyamine compound (a1), and the preferred structure is the same as that of the cyclic polyamine compound (a1). The divalent organic group is derived from an aromatic polyamine compound (C), and the preferred structure is the same as that of the aromatic polyamine compound (C). Polyurea in R 1 R includes both a divalent hydrocarbon group having a cyclic structure which may have a substituent and a divalent organic group having an aromatic ring structure which may have a substituent. 1 is a divalent hydrocarbon group derived from a cyclic polyamine compound (a1) and a divalent organic group derived from an aromatic polyamine compound (C). In other words, the divalent hydrocarbon group having a cyclic structure which may have a substituent is a divalent hydrocarbon group derived from a cyclic polyamine compound (a1), and the divalent organic group having an aromatic ring structure which may have a substituent is a divalent organic group derived from an aromatic polyamine compound (C). R 2 R is a divalent hydrocarbon group which may have a substituent. 2 is derived from the polyisocyanate compound (B), and the preferred structure is also similar to that of the polyisocyanate compound (B). R 2 is a divalent hydrocarbon group derived from the polyisocyanate compound (B). The divalent hydrocarbon which may have a substituent is a divalent hydrocarbon group derived from the polyisocyanate compound (B).

[0015] According to the present invention, it is possible to obtain a polyurea resin foam having improved foamability. The reason for this is not clear, but is thought to be as follows. When the resin is molded, the reaction product (A) of the cyclic polyamine compound (a1) and carbon dioxide produces the cyclic polyamine compound (a1) and carbon dioxide. The cyclic polyamine compound (a1) has a high carbon dioxide retention capacity and low water absorption. Therefore, it is believed that a sufficient amount of carbon dioxide can contribute to foaming, and a polyurea-based resin foam with improved foamability can be obtained. Furthermore, the aromatic polyamine compound (C) in which an amino group is directly bonded to an aromatic ring starts to react at the same time as the foamable resin composition starts to foam, which is believed to further improve the foamability. In addition, since the cyclic polyamine compound (a1) has a high carbon dioxide retention capacity, it can not only absorb carbon dioxide in the environment, but also reduce the use of other foaming agents, thereby reducing the environmental load.

[0016] <Reaction product (A) of cyclic polyamine compound (a1) with carbon dioxide> The reaction product (A) of the cyclic polyamine compound (a1) and carbon dioxide contained in the foamable resin-forming composition of the present invention acts as a foaming agent in the foamable resin-forming composition. In other words, by using the reaction product (A) of the cyclic polyamine compound (a1) and carbon dioxide as a foaming agent for molding a polyurea-based resin foam, it is possible to reduce the environmental load and obtain a polyurea-based resin foam with improved foamability.

[0017] From the viewpoint of further improving the reactivity with carbon dioxide and foaming property, the cyclic polyamine compound (a1) preferably has an amino group bonded to a primary carbon atom, which is considered to have less steric hindrance and easily absorbs carbon dioxide. The cyclic polyamine compound (a1) is a polyamine compound having a cyclic structure. The cyclic structure of the cyclic polyamine compound (a1) can be, for example, an alicyclic hydrocarbon structure, an aromatic hydrocarbon structure, or a heterocyclic structure containing a heteroatom in the ring. From the viewpoint of further improving reactivity with carbon dioxide and foaming property, it is preferable that the cyclic polyamine compound (a1) contains at least one structure selected from an alicyclic hydrocarbon structure and an aromatic hydrocarbon structure, and more preferably contains an aromatic hydrocarbon structure. In this embodiment, the term "alicyclic hydrocarbon structure" refers to a ring structure that is non-aromatic and is composed of saturated or unsaturated carbon and hydrogen, and excludes heterocyclic structures that contain heteroatoms in the ring. Also, the term "heterocyclic structure" refers to a ring structure that contains a heteroatom in the atoms that constitute the ring. The cyclic polyamine compound (a1) may be any one of a cis form, a trans form, or a mixture of a cis form and a trans form.

[0018] From the viewpoint of further improving the reactivity with carbon dioxide and the foaming property, the cyclic structure of the cyclic polyamine compound (a1) preferably contains at least one selected from the group consisting of a 5-membered ring and a 6-membered ring, and more preferably contains a 6-membered ring. In addition, from the viewpoint of further improving the reactivity with carbon dioxide and the foaming property, the cyclic polyamine compound (a1) preferably has one cyclic structure, that is, the cyclic polyamine compound (a1) is preferably a monocyclic compound. Examples of the alicyclic hydrocarbon structure of the cyclic polyamine compound (a1) include a cyclopropane ring, a cyclobutane ring, a cyclopentane ring, a cyclohexane ring, a cycloheptane ring, a cyclooctane ring, etc. Among the above ring structures, a cyclopentane ring and a cyclohexane ring are preferred, a cyclohexane ring is more preferred, and a 1,3-substituted cyclohexane ring is even more preferred.

[0019] The number of amino groups in the cyclic polyamine compound (a1) is preferably 2 or more, and preferably 6 or less, more preferably 4 or less, even more preferably 3 or less, and even more preferably 2, from the viewpoint of further improving the reactivity with carbon dioxide, curing property and foaming property. Moreover, as the amino group, from the viewpoint of further improving the reactivity with carbon dioxide, curing property, and foaming property, an amino group having a nitrogen-hydrogen bond is preferable, at least one type of amino group selected from the group consisting of a primary amino group and a secondary amino group is more preferable, and a primary amino group is even more preferable.

[0020] The cyclic polyamine compound (a1) is preferably at least one selected from o-xylylenediamine and its derivatives, m-xylylenediamine and its derivatives, p-xylylenediamine and its derivatives, and a compound represented by the following formula (II).

[0021] [ka] In the above formula (1), R 3 ~R 6 each independently represents a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms which may have at least one substituent selected from an amino group, a cyano group, a phenyl group, a hydroxyl group, and a carboxy group; R 7 ~R 12 each independently represents a hydrogen atom or a hydrocarbon group having 1 to 4 carbon atoms, x and y each independently represent an integer of 0 to 6, x+y is 1 or more and 6 or less, p and q each independently represent an integer of 0 to 4, and at least one of p and q is 1 or more.

[0022] R 3 ~R 6 are each independently a hydrogen atom, or a hydrocarbon group having from 1 to 10 carbon atoms which may have at least one substituent selected from an amino group, a cyano group, a phenyl group, a hydroxyl group, and a carboxy group, preferably a hydrogen atom, or a hydrocarbon group having from 1 to 10 carbon atoms which may have at least one substituent selected from an amino group, a cyano group, and a phenyl group, more preferably a hydrogen atom, or an alkyl group having from 1 to 4 carbon atoms which may have at least one substituent selected from an amino group, a cyano group, and a phenyl group, even more preferably a hydrogen atom, or an alkyl group having from 1 to 4 carbon atoms which may have at least one substituent selected from an amino group and a cyano group, still more preferably a hydrogen atom, or an alkyl group having from 2 to 4 carbon atoms which may have at least one substituent selected from an amino group and a cyano group, and even more preferably a hydrogen atom. R 3 ~R6 The number of carbon atoms in each of the hydrocarbon groups is independently 1 or more, and preferably 2 or more, and 10 or less, preferably 5 or less, more preferably 4 or less, and even more preferably 3 or less.

[0023] R 7 ~R 12 are each independently a hydrogen atom or a hydrocarbon group having 1 to 4 carbon atoms, preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, more preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, even more preferably a hydrogen atom or a methyl group, and even more preferably a hydrogen atom. R 7 ~R 12 The number of carbon atoms in each of the hydrocarbon groups is independently 1 or more and 4 or less, preferably 1 or 2, and more preferably 1.

[0024] p and q are each independently 0 or more, preferably 1 or more, and 4 or less, preferably 2 or less, more preferably 1, provided that at least one of p and q is 1 or more.

[0025] x and y each independently represent an integer of 0 or more and 6 or less, and x+y is 1 or more and 6 or less. From the viewpoint of further improving the carbon dioxide absorption amount and foamability, x+y is preferably 2 or more, more preferably 3 or more, and even more preferably 4 or more, and from the viewpoint of further improving the carbon dioxide absorption amount and foamability, it is preferably 5 or less, more preferably 4. That is, the alicyclic hydrocarbon structure is preferably a 5-membered ring or a 6-membered ring, and more preferably a 6-membered ring. When x+y is 4, preferably x is 1 and y is 3.

[0026] From the viewpoint of improving reactivity with carbon dioxide, curing property and foaming property, the cyclic polyamine compound (a1) preferably contains at least one selected from the group consisting of xylylenediamine and derivatives thereof, bis(aminomethyl)cyclohexane and derivatives thereof, limonenediamine and derivatives thereof, isophoronediamine and derivatives thereof, 2,5-bisaminomethylfuran and derivatives thereof, and 2,5-bis(aminomethyl)tetrahydrofuran and derivatives thereof, more preferably contains at least one selected from the group consisting of xylylenediamine and derivatives thereof, bis(aminomethyl)cyclohexane and derivatives thereof, limonenediamine and derivatives thereof, and isophoronediamine and derivatives thereof, even more preferably contains at least one selected from the group consisting of xylylenediamine and derivatives thereof, bis(aminomethyl)cyclohexane and derivatives thereof, and isophoronediamine and derivatives thereof, even more preferably contains at least one selected from the group consisting of xylylenediamine and derivatives thereof, and bis(aminomethyl)cyclohexane and derivatives thereof, and even more preferably contains at least one selected from the group consisting of xylylenediamine and derivatives thereof, and bis(aminomethyl)cyclohexane and derivatives thereof, and even more preferably contains xylylenediamine and derivatives thereof. As the cyclic polyamine compound (a1), from the viewpoint of improving reactivity with carbon dioxide, curing property and foaming property, at least one selected from the group consisting of xylylenediamine and derivatives thereof, bis(aminomethyl)cyclohexane and derivatives thereof, limonenediamine and derivatives thereof, isophoronediamine and derivatives thereof, 2,5-bisaminomethylfuran and derivatives thereof, and 2,5-bis(aminomethyl)tetrahydrofuran and derivatives thereof is preferable, at least one selected from the group consisting of xylylenediamine and derivatives thereof, bis(aminomethyl)cyclohexane and derivatives thereof, limonenediamine and derivatives thereof, and isophoronediamine and derivatives thereof is more preferable, at least one selected from the group consisting of xylylenediamine and derivatives thereof, bis(aminomethyl)cyclohexane and derivatives thereof, and isophoronediamine and derivatives thereof is even more preferable, at least one selected from the group consisting of xylylenediamine and derivatives thereof, and bis(aminomethyl)cyclohexane and derivatives thereof is even more preferable, and xylylenediamine and derivatives thereof is even more preferable.

[0027] The xylylenediamine and its derivatives include at least one selected from the group consisting of o-xylylenediamine and its derivatives, m-xylylenediamine and its derivatives, and p-xylylenediamine and its derivatives. Preferably, it is at least one selected from the group consisting of m-xylylenediamine and its derivatives, and p-xylylenediamine and its derivatives, and more preferably m-xylylenediamine and its derivatives. Examples of bis(aminomethyl)cyclohexane and derivatives thereof include at least one selected from the group consisting of 1,3-bis(aminomethyl)cyclohexane and derivatives thereof, 1,4-bis(aminomethyl)cyclohexane and derivatives thereof, and trans-1,4-bis(aminomethyl)cyclohexane and derivatives thereof, and preferably 1,3-bis(aminomethyl)cyclohexane and derivatives thereof.

[0028] Among these, from the viewpoint of improving reactivity with carbon dioxide and foaming property, the cyclic polyamine compound (a1) is preferably at least one selected from the group consisting of m-xylylenediamine and its derivatives, and 1,3-bis(aminomethyl)cyclohexane and its derivatives, and more preferably m-xylylenediamine and its derivatives.

[0029] Here, examples of the derivatives of the various amines mentioned above include compounds in which at least one hydrogen atom of an amino group is substituted with a hydrocarbon group having 1 to 10 carbon atoms which may have at least one substituent selected from the group consisting of an amino group, a cyano group, and a phenyl group, preferably an alkyl group having 1 to 4 carbon atoms which may have at least one substituent selected from the group consisting of an amino group, a cyano group, and a phenyl group, more preferably an alkyl group having 1 to 4 carbon atoms which may have at least one substituent selected from the group consisting of an amino group and a cyano group, and even more preferably an alkyl group having 2 to 4 carbon atoms which may have at least one substituent selected from the group consisting of an amino group and a cyano group. Furthermore, examples of the derivatives of the various amines include compounds in which at least a portion of the hydrogen atoms in the cyclic structure are substituted with a hydrocarbon group having 1 to 4 carbon atoms, preferably an alkyl group having 1 to 3 carbon atoms, more preferably a methyl group or an ethyl group, and even more preferably a methyl group. As described above, the cyclic polyamine compound (a1) is preferably an amine (primary amine). That is, from the viewpoint of improving reactivity with carbon dioxide and foaming property, the cyclic polyamine compound (a1) is preferably at least one selected from the group consisting of xylylenediamine and bis(aminomethyl)cyclohexane. The xylylenediamine may be at least one selected from the group consisting of o-xylylenediamine, m-xylylenediamine, and p-xylylenediamine, preferably at least one selected from the group consisting of m-xylylenediamine and p-xylylenediamine, and more preferably m-xylylenediamine. The bis(aminomethyl)cyclohexane may be at least one selected from the group consisting of 1,3-bis(aminomethyl)cyclohexane, 1,4-bis(aminomethyl)cyclohexane, and trans-1,4-bis(aminomethyl)cyclohexane, and is preferably 1,3-bis(aminomethyl)cyclohexane.

[0030] Among these, the cyclic polyamine compound (a1) is preferably at least one selected from the group consisting of m-xylylenediamine and 1,3-bis(aminomethyl)cyclohexane, and more preferably m-xylylenediamine, from the viewpoint of improving reactivity with carbon dioxide and foaming properties.

[0031] These cyclic polyamine compounds (a1) can be used alone or in combination of two or more kinds.

[0032] The maximum carbon dioxide dissociation temperature of the cyclic polyamine compound (a1), measured by the following method, is, from the viewpoint of improving the dissociation property of carbon dioxide and improving the foamability, preferably 200° C. or less, more preferably 180° C. or less, even more preferably 160° C. or less, still more preferably 150° C. or less, still more preferably 140° C. or less, still more preferably 135° C. or less, and still more preferably 130° C. or less. The lower limit of the maximum carbon dioxide dissociation temperature is not particularly limited, but is, for example, 40° C. or more. (method) The cyclic polyamine compound (a1) having absorbed carbon dioxide is heated from 23°C to 250°C at a heating rate of 10°C / min, and the temperature at which the amount of heat absorbed due to the desorption of carbon dioxide is maximized is measured, and this temperature is taken as the maximum carbon dioxide dissociation temperature. Here, the cyclic polyamine compound (a1) having absorbed carbon dioxide can be prepared, for example, by leaving 5 mmol of the cyclic polyamine compound (a1) in air at 23°C and 50% RH for 24 hours.

[0033] The acid dissociation constant (pKa) of the cyclic polyamine compound (a1) is preferably 8.0 or more, more preferably 8.5 or more, and even more preferably 9.0 or more from the viewpoint of further improving the carbon dioxide absorption amount and the foaming property, and is preferably 12.0 or less, more preferably 11.5 or less, and even more preferably 11.0 or less from the viewpoint of improving the dissociation property of carbon dioxide and the foaming property. The acid dissociation constant of the cyclic polyamine compound (a1) is a value determined by the following measurement method based on acid-base titration. (1) 0.2 g of the cyclic polyamine compound (a1) is dissolved in 30 mL of purified water. (2) The solution obtained in (1) above is titrated with a 0.1 N perchloric acid-acetic acid solution using an automatic potentiometric titrator (e.g., AT-610, manufactured by Kyoto Electronics Manufacturing Co., Ltd.) to calculate the acid dissociation constant (pKa). The temperature during measurement shall be 25±2°C.

[0034] The molecular weight of the cyclic polyamine compound (a1) is preferably 110 or more, more preferably 120 or more, and even more preferably 130 or more, from the viewpoint of suppressing weight loss during heat treatment for dissociating carbon dioxide. And, from the viewpoint of further improving the carbon dioxide absorption amount and foaming property, it is preferably 250 or less, more preferably 200 or less, and even more preferably 180 or less.

[0035] The maximum endothermic temperature of the cyclic polyamine compound (a1), measured by the following method, is preferably 130° C. or higher, more preferably 140° C. or higher, and even more preferably 150° C. or higher, from the viewpoint of suppressing weight loss during heat treatment for dissociating carbon dioxide. And, from the viewpoint of improving the carbon dioxide absorption amount and foamability, it is preferably 260° C. or lower, more preferably 230° C. or lower, even more preferably 210° C. or lower, and even more preferably 190° C. or lower. (method) The cyclic polyamine compound (a1) is heated from 23°C to 350°C at a heating rate of 10°C / min, and the temperature at which the amount of heat absorbed due to the volatilization of the cyclic polyamine compound (a1) becomes maximum is measured, and this temperature is regarded as the maximum endothermic temperature of the amine compound (a1).

[0036] From the viewpoint of further improving the carbon dioxide absorption amount and foaming property, the amine value of the cyclic polyamine compound (a1) is preferably 400 mg KOH / g or more, more preferably 500 mg KOH / g or more, more preferably 600 mg KOH / g or more, even more preferably 650 mg KOH / g or more, and even more preferably 700 mg KOH / g or more. And it is preferably 1500 mg KOH / g or less, more preferably 1400 mg KOH / g or less, even more preferably 1300 mg KOH / g or less, even more preferably 1100 mg KOH / g or less, even more preferably 1000 mg KOH / g or less, and even more preferably 850 mg KOH / g or less. The amine value indicates the amount of amine in the compound, and refers to the number of mg of potassium hydroxide (KOH) equivalent to the acid required to neutralize 1 g of the compound. The amine value can be measured by the following method in accordance with JIS K7237-1995. (1) Dissolve 0.1 g of cyclic polyamine compound (a1) in 20 mL of acetic acid. (2) The solution obtained in (1) above is titrated with a 0.1 N perchloric acid-acetic acid solution using an automatic potentiometric titrator (e.g., AT-610 manufactured by Kyoto Electronics Manufacturing Co., Ltd.) to calculate the amine value.

[0037] When the cyclic polyamine compound (a1) is allowed to stand for one week under an air environment of 23°C and 50% RH, the mass increase rate of the cyclic polyamine compound (a1) calculated by the following formula is, from the viewpoint of improving foamability, preferably 10% by mass or more, more preferably 15% by mass or more, even more preferably 18% by mass or more, still more preferably 20% by mass or more, still more preferably 23% by mass or more, and preferably 50% by mass or less, more preferably 45% by mass or less, still more preferably 40% by mass or less, still more preferably 30% by mass or less, and still more preferably 28% by mass or less. Mass increase rate of cyclic polyamine compound (a1) [mass%] = 100 × mass increase amount (g) of cyclic polyamine compound (a1) / (mass (g) of cyclic polyamine compound (a1) + mass increase amount (g) of cyclic polyamine compound (a1)) The mass increase rate of the cyclic polyamine compound (a1) can be specifically measured by the method described in the Examples.

[0038] The reaction product (A) of the cyclic polyamine compound (a1) and carbon dioxide can be obtained, for example, by contacting the cyclic polyamine compound (a1) with a gas containing carbon dioxide to react the cyclic polyamine compound (a1) with carbon dioxide. That is, a preferred method for producing the reaction product (A) of the cyclic polyamine compound (a1) and carbon dioxide is to contact the cyclic polyamine compound (a1) with a gas containing carbon dioxide to react the cyclic polyamine compound (a1) with carbon dioxide.

[0039] The gas containing carbon dioxide may be carbon dioxide alone or a mixture of carbon dioxide and an inert gas. It is convenient and preferable to use air as the gas containing carbon dioxide. Here, the "inert gas" refers to a gas that does not affect the reaction when obtaining a polyurea resin foam described later. Examples of the inert gas include nitrogen and oxygen. It is preferable to further include a step of contacting the cyclic polyamine compound (a1) with a gas containing carbon dioxide having a carbon dioxide concentration of 0.01 volume % or more and 10 volume % or less to react the cyclic polyamine compound (a1) with carbon dioxide to obtain the reactant (A). The carbon dioxide concentration is preferably 0.01% by volume or more, more preferably 0.02% by volume or more, even more preferably 0.03% by volume or more, and preferably 10% by volume or less, more preferably 5% by volume or less, even more preferably 1% by volume or less, still more preferably 0.5% by volume or less, and even more preferably 0.1% by volume or less. It is further preferable that the gas having a carbon dioxide concentration of 0.01% by volume or more and 10% by volume or less is air.

[0040] There is no limitation on the method for contacting the cyclic polyamine compound (a1) with a gas containing carbon dioxide, but it is preferable to store the cyclic polyamine compound (a1) in the gas containing carbon dioxide at 30° C. or less while stirring or shaking until the mass increase rate reaches a target range. There is no limitation on the pressure when the cyclic polyamine compound (a1) is contacted with a gas containing carbon dioxide, but it is preferable to store it under atmospheric pressure or under pressure, and it is more preferable to store it under atmospheric pressure. The time for contacting with the gas containing carbon dioxide may be adjusted depending on the temperature, pressure, and amount of carbon dioxide contained in the gas described above, but when air is used as the gas containing carbon dioxide and the storage is performed under atmospheric pressure, the time for contacting with the gas containing carbon dioxide is preferably 1 hour or more, more preferably 1 day or more, even more preferably 5 days or more, still more preferably 10 days or more, still more preferably 15 days or more, and still more preferably 30 days or more. There is no upper limit, but 100 days or less is preferable.

[0041] The reaction product (A) of the cyclic polyamine compound (a1) and carbon dioxide preferably contains at least one member selected from the group consisting of carbamic acid, carbamate salts, carbonate salts and hydrogencarbonate salts.

[0042] The reaction product (A) of the cyclic polyamine compound (a1) and carbon dioxide forms a salt as described above, and the molar ratio of the portion derived from the cyclic polyamine compound (a1) to the portion derived from carbon dioxide contained in the reaction product (A) [cyclic polyamine compound (a1) / carbon dioxide] is preferably 70 / 30 to 30 / 70, more preferably 60 / 40 to 40 / 60, and even more preferably 55 / 45 to 45 / 55. The water content in the reaction product (A) is preferably 50% by mass or less, more preferably 15% by mass or less, even more preferably 10% by mass or less, and even more preferably 5% by mass or less. When the water content is within the above range, the foamability can be improved. As described above, the reaction product (A) of the cyclic polyamine compound (a1) and carbon dioxide can be obtained by contacting the cyclic polyamine compound (a1) with a gas containing carbon dioxide, but it is preferable not to add moisture at that time.

[0043] <Polyisocyanate compound (B)> The polyisocyanate compound (B) is not particularly limited as long as it contains a compound having two or more isocyanate groups, and a conventionally known compound can be used. The polyisocyanate compound (A) is preferably a compound having two or more isocyanate groups. Examples of diisocyanate compounds having two isocyanate groups include aliphatic isocyanate compounds such as 1,6-hexamethylene diisocyanate (HDI), 2,2,4-trimethylhexamethylene diisocyanate, methylene diisocyanate, isopropylene diisocyanate, lysine diisocyanate, lysine diisocyanate methyl ester, and 1,5-octylene diisocyanate; 4,4'-dicyclohexylmethane diisocyanate, isophorone diisocyanate (IPDI), norbornene diisocyanate, hydrogenated tolylene diisocyanate, methylcyclohexane diisocyanate, and isopropyl Examples of the isocyanate compounds include alicyclic isocyanate compounds such as denbis(4-cyclohexyl isocyanate) and dimer acid diisocyanate; and aromatic isocyanate compounds such as 2,4- or 2,6-tolylene diisocyanate (TDI), 4,4'-diphenylmethane diisocyanate (MDI), 1,5-naphthylene diisocyanate, p- or m-xylylene diisocyanate (XDI), tolidine diisocyanate, p-phenylene diisocyanate, diphenyl ether diisocyanate, diphenyl sulfone diisocyanate, dianisidine diisocyanate, and tetramethyl-m-xylylene diisocyanate. Examples of isocyanate compounds having three or more isocyanate groups include triphenylmethane triisocyanate, triisocyanate phenylthiophosphate, polymethylene polyphenylene polyisocyanate (polymeric MDI), isocyanurate modified products which are trimers of HDI or TDI, and biuret modified products. The isocyanate compound (B) can be used alone or in combination of two or more kinds.

[0044] Among these, as the polyisocyanate compound (B), a diisocyanate having two isocyanate groups is preferable, at least one selected from the group consisting of isophorone diisocyanate (IPDI), 1,6-hexamethylene diisocyanate (HDI) and 4,4'-diphenylmethane diisocyanate (MDI) is more preferable, at least one selected from the group consisting of isophorone diisocyanate (IPDI) and 1,6-hexamethylene diisocyanate (HDI) is even more preferable, and isophorone diisocyanate (IPDI) is even more preferable.

[0045] <Aromatic polyamine compound (C)> The foamable resin composition of the present invention contains an aromatic polyamine compound (C). The "aromatic polyamine compound (C)" in the resin foam-forming composition of the present invention refers to a polyamine in which an amino group is directly bonded to an aromatic ring. The aromatic polyamine compound (C) initiates a reaction at the same time that the foamable resin-forming composition starts to foam, and therefore the resulting foamed polyurea resin has a high molecular weight, and the foamability is further improved. The aromatic polyamine compound (C) has a plurality of amino groups in one molecule. When the aromatic polyamine compound (C) has only one aromatic ring in one molecule, it has a plurality of amino groups on one aromatic ring. When the aromatic polyamine compound (C) has a plurality of aromatic rings in one molecule, it has one or a plurality of amino groups on one aromatic ring. However, it is preferable that the aromatic polyamine compound (C) has a plurality of aromatic rings in one molecule and has one amino group on one aromatic ring.

[0046] The aromatic ring of the aromatic polyamine compound (C) is preferably at least one type selected from the group consisting of a 5-membered ring and a 6-membered ring, and more preferably a 6-membered ring.

[0047] The number of amino groups in the aromatic polyamine compound (C) is preferably 2 or more and preferably 6 or less, more preferably 4 or less, even more preferably 3 or less, and even more preferably 2. The amino group is preferably an amino group having a nitrogen-hydrogen bond, more preferably at least one type of amino group selected from the group consisting of primary amino groups and secondary amino groups, and even more preferably a primary amino group.

[0048] The aromatic polyamine compound (C) is preferably a compound represented by the following formula (III).

[0049] [ka] (In formula (III), X is a divalent organic group.)

[0050] X may be a divalent organic group, and may be at least one of an alkylene group which may have a substituent, a polyoxyalkylene group which may have a substituent, an ether bond, an ester bond, an amide bond, and a single bond, or may be an organic group consisting of a combination of these. The aromatic polyamine compound (C) is more preferably a compound represented by the following formula (IIIa): The compound represented by formula (IIIa) is polytetramethylene oxide-di-p-aminobenzoate.

[0051] [ka] (In formula (IIIa), n is preferably 1 to 20.)

[0052] From the viewpoint of improving the foamability, n is preferably 1 to 20, more preferably 2 to 15, even more preferably 2 to 10, and still more preferably 2 to 6. Commercially available products of the compound represented by the formula (IIIa) include "ELASMER 1000P" (molecular weight 1238, amine value 84.8 mg KOH / g), "ELASMER 650P" (molecular weight 888, amine value 126 mg KOH / g), and "ELASMER 250P" (molecular weight 488, amine value 220 mg KOH / g) manufactured by Kumiai Chemical Industry Co., Ltd.; and "ETHACURE 100 PLUS" (molecular weight 178, amine value 89 mg KOH / g), "ETHACURE 300" (molecular weight 214, amine value 107 mg KOH / g), and "ETHACURE 420" (molecular weight 310, amine value 155 mg KOH / g) manufactured by Mitsui Chemical Fine Co., Ltd. The aromatic polyamine compounds (C) can be used alone or in combination of two or more kinds.

[0053] The molecular weight of the aromatic polyamine compound (C) is preferably 300 to 5000, more preferably 300 to 2000, even more preferably 300 to 1500, still more preferably 300 to 1000, still more preferably 300 to 700, and still more preferably 400 to 600. When the molecular weight of the aromatic polyamine compound (C) is within the above range, the foaming property can be improved, and furthermore, flexibility can be imparted to the obtained polyurea resin foam.

[0054] The amine value of the aromatic polyamine compound (C) is preferably 50 to 1000 mgKOH / g, more preferably 50 to 600 mgKOH / g, even more preferably 50 to 400 mgKOH / g, even more preferably 50 to 300 mgKOH / g, even more preferably 70 to 300 mgKOH / g, even more preferably 80 to 300 mgKOH / g, and even more preferably 100 to 300 mgKOH / g. The amine value indicates the amount of amine in the compound, and refers to the number of mg of potassium hydroxide (KOH) equivalent to the acid required to neutralize 1 g of the compound. When the amine value of the aromatic polyamine compound (C) is in the above range, the foamability can be improved, and further, flexibility can be imparted to the obtained polyurea resin foam. The amine value can be measured by the following method in accordance with JIS K7237-1995. (1) Dissolve 0.1 g of aromatic polyamine compound (C) in 20 mL of acetic acid. (2) The solution obtained in (1) above is titrated with a 0.1 N perchloric acid-acetic acid solution using an automatic potentiometric titrator (e.g., AT-610 manufactured by Kyoto Electronics Manufacturing Co., Ltd.) to calculate the amine value.

[0055] <Composition of foamable resin composition> As described above, the foamable resin forming composition contains the reaction product (A) of the cyclic polyamine compound (a1) with carbon dioxide, the polyisocyanate compound (B) and the aromatic polyamine compound (C), and preferably has the following composition.

[0056] In the foamable resin composition, the molar ratio ((A) / (C)) of the reaction product (A) of the cyclic polyamine compound (a1) and carbon dioxide to the aromatic polyamine compound (C) is preferably 3 / 7 to 9 / 1, more preferably 3 / 7 to 8 / 2, even more preferably 4 / 6 to 8 / 2, still more preferably 5 / 5 to 8 / 2, still more preferably 5 / 5 to 7 / 3, and still more preferably 6 / 4 to 7 / 3. When the molar ratio of the reaction product (A) of the cyclic polyamine compound (a1) and carbon dioxide to the aromatic polyamine compound (C) is within the above range, the foamability can be improved and the obtained polyurea resin foam can be given flexibility.

[0057] In the foamable resin forming composition, the ratio of the total number of amino groups of the reaction product (A) of the cyclic polyamine compound (a1) and carbon dioxide and the aromatic polyamine compound (C) to the number of isocyanate groups of the polyisocyanate compound (B) (the number of amino groups / the number of isocyanate groups) is preferably 0.5 or more and 1.5 or less. The ratio of the number of amino groups in the foaming agent (A) to the number of isocyanate groups in the polyisocyanate compound (B) (the number of amino groups / the number of isocyanate groups) is preferably 0.5 or more, more preferably 0.6 or more, even more preferably 0.7 or more, even more preferably 0.8 or more, and even more preferably 0.9 or more, from the viewpoint of improving foamability. From the same viewpoint, it is preferably 1.5 or less, more preferably 1.4 or less, even more preferably 1.3 or less, even more preferably 1.2 or less, and even more preferably 1.1 or less.

[0058] The foam-forming composition of the present invention may contain a foaming agent other than the reaction product (A) of the cyclic polyamine compound (a1) and carbon dioxide, but it is preferable that it is substantially free of the foaming agent. The content of the foaming agent other than the foaming agent (A) in the foam-forming composition is preferably 5 mass% or less, more preferably 3 mass% or less, even more preferably 1 mass% or less, even more preferably 0.5 mass% or less, even more preferably 0.1 mass% or less, even more preferably 0 mass%, and even more preferably none. Examples of blowing agents other than reactant (A) include halogen-containing hydrocarbons of the fluorocarbon type, such as chlorofluorocarbons and fluorocarbons; alicyclic hydrocarbons, such as cyclopentane; organic blowing agents, such as dinitropentamethylenetetramine, azodicarbonamide, and p,p'-oxybisbenzenesulfonylhydrazide; and inorganic blowing agents, such as sodium hydrogen carbonate.

[0059] The foamable resin forming composition may further contain other components, such as a filler, a modifying component such as a plasticizer, a flow adjusting component such as a thixotropic agent, a pigment, a leveling agent, a tackifier, elastomer fine particles, a curing accelerator, a foam stabilizer, and a chemical foaming agent, depending on the application. The resin foam-forming composition may contain a solvent, but preferably does not substantially contain a solvent, which is highly environmentally friendly and allows a foam to be easily obtained. However, from the viewpoint of effectively obtaining the effects of the present invention, the total content of the reaction product (A) of the cyclic polyamine compound (a1) and carbon dioxide, the polyisocyanate compound (B) and the aromatic polyamine compound (C) in the foamable resin forming composition, when the total solid content contained in the foamable resin forming composition of the present invention is taken as 100 mass%, is preferably 50 mass% or more, more preferably 60 mass% or more, even more preferably 70 mass% or more, even more preferably 80 mass% or more, even more preferably 90 mass% or more, even more preferably 95 mass% or more, even more preferably 98 mass% or more, even more preferably 99 mass% or more, and from the same viewpoint, is preferably 100 mass% or less.

[0060] <Method for preparing foamable resin composition> The method for preparing the foamable resin forming composition is not particularly limited, and the composition can be produced by mixing the reaction product (A) of the cyclic polyamine compound (a1) and carbon dioxide, the polyisocyanate compound (B), the aromatic polyamine compound (C), and other components as necessary, using known methods and devices.

[0061] [Polyurea resin foam and method for producing polyurea resin foam] The polyurea-based resin foam of the present invention is produced by foaming the foam-forming composition of the present invention. Therefore, the polyurea-based resin foam of the present invention contains a polyurea having a repeating unit represented by the following general formula (I). The polyurea having a repeating unit represented by the following general formula (I) contained in the polyurea-based resin foam of the present invention is the same as that described in the above section [Foam-forming composition]. [ka] (In formula (I), R 1represents a divalent hydrocarbon group having a cyclic structure which may be substituted, and a divalent organic group having an aromatic ring structure which may be substituted, R 2 is a divalent hydrocarbon group which may have a substituent. In addition, in the divalent organic group having an aromatic ring structure, the aromatic ring is bonded to a nitrogen atom.

[0062] R 1 includes both a divalent hydrocarbon group having a cyclic structure which may have a substituent and a divalent organic group having an aromatic ring structure which may have a substituent. The divalent hydrocarbon group is derived from a cyclic polyamine compound (a1), and the preferred structure is the same as that of the cyclic polyamine compound (a1). The divalent organic group is derived from an aromatic polyamine compound (C), and the preferred structure is the same as that of the aromatic polyamine compound (C). R 2 R is a divalent hydrocarbon group which may have a substituent. 2 is derived from the polyisocyanate compound (B), and the preferred structure is also similar to that of the polyisocyanate compound (B).

[0063] The polyurea-based resin foam of the present invention may be produced by any method as long as it is produced by foam-molding the foam-forming composition. A preferred method for producing a polyurea-based resin foam includes a step of foam-molding the foam-forming composition.

[0064] In the step of foaming the foamable resin composition, for example, the foamable resin composition is heated to generate a cyclic polyamine compound (a1) and carbon dioxide from the reactant (A), and the foamable resin composition is foamed by the carbon dioxide, and the foamable resin composition is cured by the reaction of the generated cyclic polyamine compound (a1), aromatic polyamine compound (C), and polyisocyanate compound (B). By such a method, a polyurea-based resin foam can be obtained.

[0065] The heating temperature and heating time in the step of foaming the foamable resin composition can be appropriately selected, but from the viewpoints of reaction rate, productivity, and prevention of decomposition of raw materials, etc., the temperature is preferably 50 to 250° C., more preferably 100 to 200° C., and even more preferably 120 to 180° C. The reaction time is preferably 10 minutes to 12 hours, and more preferably 15 minutes to 4 hours. The pressure in the step of foaming the foamable resin composition can be appropriately selected, but it is preferable to foam the composition under atmospheric pressure.

[0066] The molecular weight of the aromatic polyamine compound (C) used in the method for producing a polyurea resin foam is preferably 300 to 5000, more preferably 300 to 2000, even more preferably 300 to 1500, still more preferably 300 to 1000, still more preferably 300 to 700, and still more preferably 400 to 600. When the molecular weight of the aromatic polyamine compound (C) is within the above range, the foamability can be improved and further flexibility can be imparted to the obtained polyurea resin foam.

[0067] The amine value of the aromatic polyamine compound (C) used in the method for producing a polyurea resin foam is preferably 50 to 1000 mgKOH / g, more preferably 50 to 600 mgKOH / g, even more preferably 50 to 400 mgKOH / g, even more preferably 50 to 300 mgKOH / g, even more preferably 70 to 300 mgKOH / g, even more preferably 80 to 300 mgKOH / g, and even more preferably 100 to 300 mgKOH / g. The amine value indicates the amount of amine in the compound, and refers to the number of mg of potassium hydroxide (KOH) equivalent to the acid required to neutralize 1 g of the compound. When the amine value of the aromatic polyamine compound (C) is within the above range, the foamability can be improved, and further, flexibility can be imparted to the obtained polyurea resin foam. The amine value can be measured by the following method in accordance with JIS K7237-1995. (1) Dissolve 0.1 g of aromatic polyamine compound (C) in 20 mL of acetic acid. (2) The solution obtained in (1) above is titrated with a 0.1 N perchloric acid-acetic acid solution using an automatic potentiometric titrator (e.g., AT-610 manufactured by Kyoto Electronics Manufacturing Co., Ltd.) to calculate the amine value.

[0068] The method for producing a polyurea-based resin foam according to the present invention preferably further comprises a step of contacting the cyclic polyamine compound (a1) with a gas containing carbon dioxide to react the cyclic polyamine compound (a1) with carbon dioxide to obtain a reactant (A) before the step of foaming the foam-forming composition. That is, the method for producing a polyurea-based resin foam according to the present invention preferably comprises a step of contacting the cyclic polyamine compound (a1) with a gas containing carbon dioxide to obtain a reactant (A), and a step of mixing the obtained reactant (A) with a polyisocyanate compound (B) and an aromatic polyamine compound (C) to obtain a foam-forming composition.

[0069] The gas containing carbon dioxide may be carbon dioxide alone or a mixture of carbon dioxide and an inert gas. It is convenient and preferable to use air as the gas containing carbon dioxide. Here, the "inert gas" refers to a gas that does not affect the reaction when obtaining a polyurea resin foam described later. Examples of the inert gas include nitrogen and oxygen. It is preferable to further include a step of contacting the cyclic polyamine compound (a1) with a gas containing carbon dioxide having a carbon dioxide concentration of 0.01 volume % or more and 10 volume % or less to react the cyclic polyamine compound (a1) with carbon dioxide to obtain the reactant (A). The carbon dioxide concentration is preferably 0.01% by volume or more, more preferably 0.02% by volume or more, even more preferably 0.03% by volume or more, and preferably 10% by volume or less, more preferably 5% by volume or less, even more preferably 1% by volume or less, still more preferably 0.5% by volume or less, and even more preferably 0.1% by volume or less. It is further preferable that the gas having a carbon dioxide concentration of 0.01% by volume or more and 10% by volume or less is air.

[0070] There is no limitation on the method of contacting the cyclic polyamine compound (a1) with a gas containing carbon dioxide, but it is preferable to store the cyclic polyamine compound (a1) in the gas containing carbon dioxide at 30° C. or less while stirring or shaking until the mass increase rate reaches a target range. There is no limitation on the pressure when the cyclic polyamine compound (a1) is contacted with a gas containing carbon dioxide, but it is preferable to store it under atmospheric pressure or under pressure, and it is more preferable to store it under atmospheric pressure.

[0071] The reaction product (A) of the cyclic polyamine compound (a1) and carbon dioxide preferably contains at least one member selected from the group consisting of carbamic acid, carbamate salts, carbonate salts and hydrogencarbonate salts. EXAMPLES

[0072] The present invention will be described below with reference to examples, but the present invention is not limited to the scope of the examples. In the examples, various measurements were carried out by the following methods.

[0073] (Acid dissociation constant (pKa) of cyclic polyamine compounds) The acid dissociation constant of the amine compound was determined by the following measurement method. (1) 0.2 g of a cyclic polyamine compound was dissolved in 30 mL of purified water. (2) The solution obtained in (1) above was titrated with a 0.1 N perchloric acid-acetic acid solution using an automatic potentiometric titrator (AT-610, manufactured by Kyoto Electronics Manufacturing Co., Ltd.) to calculate the acid dissociation constant (pKa). The temperature during the measurements was 25±2°C.

[0074] (Amine value of cyclic polyamine compounds and aromatic polyamine compounds) The amine value was measured by the following method in accordance with JIS K7237-1995. (1) 0.1 g of a cyclic polyamine compound or an aromatic polyamine compound was dissolved in 20 mL of acetic acid. (2) The solution obtained in (1) above was titrated with a 0.1 N perchloric acid-acetic acid solution using an automatic potentiometric titrator (AT-610, manufactured by Kyoto Electronics Manufacturing Co., Ltd.) to calculate the amine value.

[0075] (Maximum endothermic temperature of cyclic polyamine compound) The cyclic polyamine compound was subjected to DTA measurement as follows to measure the maximum endothermic temperature of the cyclic polyamine compound. First, the cyclic polyamine compound was subjected to differential scanning calorimetry using a differential thermogravimetry meter (product name: DTG-60, manufactured by Shimadzu Corporation) under the conditions of a measurement temperature range of 23 to 350°C, a heating rate of 10°C / min, and a nitrogen atmosphere. From the DTA curve obtained by this, the temperature at which the amount of endothermic heat associated with the volatilization of the cyclic polyamine compound was maximized was calculated, and this temperature was determined as the maximum endothermic temperature of the cyclic polyamine compound.

[0076] (Maximum carbon dioxide (CO2) dissociation temperature of cyclic polyamine compounds) A carbon dioxide concentration meter and a petri dish were placed in an openable desiccator (inner dimensions: 370 mm x 260 mm x 272 mm). Then, a cyclic polyamine compound (5 mmol) was added to the petri dish in the desiccator, the door was immediately closed, and the cyclic polyamine compound was left in the desiccator for 24 hours under an air environment of 23°C and 50% RH. The initial concentration of carbon dioxide was adjusted to about 400 ppm. Next, the cyclic polyamine compound was taken out from the desiccator to obtain a cyclic polyamine compound having absorbed carbon dioxide. The cyclic polyamine compound having absorbed carbon dioxide was subjected to DSC measurement as follows to measure the maximum carbon dioxide dissociation temperature of the cyclic polyamine compound. First, the cyclic polyamine compound was subjected to differential scanning calorimetry using a differential thermogravimetry meter (product name: DTG-60, manufactured by Shimadzu Corporation) under conditions of a measurement temperature range of 23 to 250°C, a heating rate of 10°C / min, and a nitrogen atmosphere. From the DSC curve obtained by this, the temperature at which the endothermic heat associated with the desorption of carbon dioxide was maximized was calculated, and this temperature was determined as the maximum carbon dioxide dissociation temperature of the cyclic polyamine compound.

[0077] (Water Content of Reaction Product (A) of Cyclic Polyamine Compound (a1) with Carbon Dioxide and Composition of Blowing Agent) The water content and composition of the reaction product (A) produced in the Production Examples were measured using an organic trace elemental analyzer (Microcorder JM10, manufactured by J Science Lab Co., Ltd.).

[0078] (Evaluation of foaming properties) The foamability of the foamable resin composition was evaluated based on the volume increase rate (times, expansion ratio) of the polyurea resin foam. The volume increase rate is calculated by dividing the thickness after foaming by the thickness before foaming when foaming is performed in a rectangular parallelepiped container with a fixed bottom shape (bottom area). A larger volume increase rate means better foamability.

[0079] In the examples, the following cyclic polyamine compound (a1), polyisocyanate compound (B), and aromatic polyamine compound (C) were used. (Cyclic polyamine compound (a1)) MXDA: meta-xylylenediamine (acid dissociation constant (pKa): 9.5, amine value: 824 mg KOH / g, maximum endothermic temperature: 183.5°C, carbon dioxide (CO2) maximum dissociation temperature: 135.5°C, manufactured by Mitsubishi Gas Chemical Co., Ltd.) (Polyisocyanate compound (B)) IPDI: Isophorone diisocyanate (Tokyo Chemical Industry Co., Ltd.) HDI: 1,6-hexamethylene diisocyanate (Tokyo Chemical Industry Co., Ltd.) (Aromatic polyamine compound (C)) 250P: Elasmer 250P (polytetramethylene oxide-di-p-aminobenzoate, molecular weight (catalog value) 488, amine value 220 mgKOH / g, manufactured by Kumiai Chemical Industry Co., Ltd.) 1000P: Elasmer 1000P (polytetramethylene oxide-di-p-aminobenzoate, molecular weight (catalog value) 1238, amine value 84.8 mgKOH / g, manufactured by Kumiai Chemical Industry Co., Ltd.)

[0080] Example 1 (1) Preparation of reaction product (A) of cyclic polyamine compound (a1) with carbon dioxide (absorption of carbon dioxide into amine compound) MXDA, a cyclic polyamine compound, was placed in a container and left to stand for one week in an air environment of 23°C and 50% RH. This caused MXDA to react with carbon dioxide in the air, obtaining a reaction product of MXDA and carbon dioxide (MXDA carbonate). Here, in order to suppress uneven reaction, the container containing the cyclic polyamine compound was shaken as needed to prevent unreacted MXDA from being produced. The moisture content of the obtained reaction product (MXDA carbonate) was 0% by mass. Next, the mass increase of MXDA was measured, and the mass increase rate of the cyclic polyamine compound was calculated from the following formula: The mass increase rate was 24.1% by mass. Mass increase rate of cyclic polyamine compound [mass%] = 100 × mass increase amount of cyclic polyamine compound (g) / (initial mass (g) of cyclic polyamine compound + mass increase amount of cyclic polyamine compound (g))

[0081] (2) Production of foamable resin composition To the reaction product (A) of MXDA and carbon dioxide (carbonate of MXDA), IPDI (polyisocyanate compound (B)) and 250P (aromatic polyamine compound (C)) were added and mixed by stirring for 1 minute to obtain a foamable resin composition. The amounts of the reaction product of MXDA and carbon dioxide and 250P were adjusted so that the molar ratio ((A) / (C)) of the reaction product of MXDA and carbon dioxide to 250P was 6 / 4, and the amount of IPDI was adjusted so that the sum of the number of amino groups of MXDA and 250P / the number of isocyanate groups of IPDI was 1 / 1 in molar ratio.

[0082] (3) Manufacture of polyurea resin foam The foamable resin composition obtained in (2) was placed in a rectangular mold having a bottom surface of 12 cm x 12 cm so as to have a thickness of about 3 mm, and heated using a hot air dryer at a heating temperature of 150°C for a heating time of 30 minutes to harden and foam the foamable resin composition. This resulted in a polyurea-based resin foam. It was also visually confirmed that a foam structure was formed in the obtained polyurea-based resin foam. The foamability of the obtained polyurea-based resin foam was also evaluated. The results are shown in Table 1.

[0083] Examples 2 to 4 and Comparative Examples 1 to 2 Polyurea resin foams were obtained in the same manner as in Example 1, except that the amount of the reaction product of MXDA and carbon dioxide obtained in the same manner as in Example 1(1) and 250P were changed to the ratio shown in Table 1. In Comparative Example 1, 250P was not used, and in Comparative Example 2, the reaction product of MXDA and carbon dioxide was not used. The foaming properties of the resulting polyurea resin foam were evaluated, and the results are shown in Table 1.

[0084] [Table 1]

[0085] Example 5 A polyurea resin foam was obtained in the same manner as in Example 1, except that IPDI as the polyisocyanate compound (B) was changed to HDI. The foaming properties of the resulting polyurea resin foam were evaluated, and the results are shown in Table 2.

[0086] Examples 6 to 9 and Comparative Examples 3 to 4 Polyurea resin foams were obtained in the same manner as in Example 5, except that the amount of the reaction product of MXDA and carbon dioxide obtained in the same manner as in Example 1(1) and 250P were changed to the ratio shown in Table 2. In Comparative Example 3, 250P was not used, and in Comparative Example 4, the reaction product of MXDA and carbon dioxide was not used. The foaming properties of the resulting polyurea resin foam were evaluated, and the results are shown in Table 2.

[0087] [Table 2]

[0088] Example 10 A polyurea resin foam was obtained in the same manner as in Example 1, except that the aromatic polyamine compound (C) 250P was changed to 1000P. The foaming properties of the resulting polyurea resin foam were evaluated, and the results are shown in Table 3.

[0089] Examples 11 to 14 and Comparative Examples 5 to 6 Polyurea resin foams were obtained in the same manner as in Example 10, except that the amount of the reaction product of MXDA and carbon dioxide obtained in the same manner as in Example 1(1) and 1000P were changed to the ratio shown in Table 3. In Comparative Example 5, 1000P was not used, and in Comparative Example 6, the reaction product of MXDA and carbon dioxide was not used. The foaming properties of the resulting polyurea resin foam were evaluated, and the results are shown in Table 3.

[0090] [Table 3]

[0091] Example 15 A polyurea resin foam was obtained in the same manner as in Example 10, except that IPDI as the polyisocyanate compound (B) was changed to HDI. The foaming properties of the resulting polyurea resin foam were evaluated, and the results are shown in Table 4.

[0092] Examples 16 to 18 and Comparative Examples 7 to 8 Polyurea resin foams were obtained in the same manner as in Example 15, except that the amount of the reaction product of MXDA and carbon dioxide obtained in the same manner as in Example 1(1) and 1000P were changed to the ratio shown in Table 4. In Comparative Example 7, 1000P was not used, and in Comparative Example 8, the reaction product of MXDA and carbon dioxide was not used. The foaming properties of the resulting polyurea resin foam were evaluated, and the results are shown in Table 4.

[0093] [Table 4]

[0094] From Tables 1 to 4, it is seen that the foam-forming compositions of the Examples can produce polyurea-based resin foams with improved foamability without using conventional foaming agents that have a large environmental impact. In addition, the foam-forming compositions of the Examples can be produced by absorbing carbon dioxide in the environment, which also contributes to reducing the environmental impact.

Claims

1. A foam-forming composition for obtaining a polyurea-based resin foam, comprising: The composition contains a reaction product (A) of a cyclic polyamine compound (a1) with carbon dioxide, a polyisocyanate compound (B), and an aromatic polyamine compound (C), the cyclic polyamine compound (a1) is at least one selected from the group consisting of m-xylylenediamine and its derivatives, and 1,3-bis(aminomethyl)cyclohexane and its derivatives; The polyisocyanate compound (B) is at least one selected from the group consisting of isophorone diisocyanate, 1,6-hexamethylene diisocyanate, and 4,4'-diphenylmethane diisocyanate; A foam-forming composition, wherein the aromatic polyamine compound (C) is a compound represented by the following formula (IIIa): 【Chemistry 1】 (In formula (IIIa), n is 1 to 20.)

2. The foamable resin-forming composition according to claim 1, wherein the molar ratio ((A) / (C)) of the reactant (A) of the cyclic polyamine compound (a1) and carbon dioxide to the aromatic polyamine compound (C) in the foamable resin-forming composition is 3 / 7 to 8 / 2.

3. 2. The resin foam-forming composition according to claim 1, wherein the aromatic polyamine compound (C) has an amine value of 70 to 300 mgKOH / g.

4. 2. The foamable resin composition according to claim 1, which is a foamable resin composition for obtaining a polyurea-based resin foam containing a polyurea having a repeating unit represented by the following general formula (I): 【Chemistry 1】 (In formula (I), R 1 is a divalent hydrocarbon group derived from the cyclic polyamine compound (a1) and a divalent organic group derived from the aromatic polyamine compound (C), R 2 is a divalent hydrocarbon group derived from the polyisocyanate compound (B).

5. 2. The foamable resin forming composition according to claim 1, wherein the polyisocyanate compound (B) is isophorone diisocyanate.

6. 2. The resin foam-forming composition according to claim 1, wherein the cyclic polyamine compound (a1) is at least one selected from the group consisting of m-xylylenediamine and derivatives thereof.

7. 2. The resin foam-forming composition according to claim 1, wherein the cyclic polyamine compound (a1) is at least one member selected from the group consisting of 1,3-bis(aminomethyl)cyclohexane and derivatives thereof.

8. 2. The resin foam-forming composition according to claim 1, wherein the cyclic polyamine compound (a1) is at least one member selected from the group consisting of m-xylylenediamine and 1,3-bis(aminomethyl)cyclohexane.

9. 2. The resin foam-forming composition according to claim 1, wherein the cyclic polyamine compound (a1) is m-xylylenediamine.

10. 2. The foamable resin forming composition according to claim 1, wherein the content of the foaming agent other than the reaction product (A) of the cyclic polyamine compound (a1) and carbon dioxide is 5 mass % or less.

11. 2. The foamable resin-forming composition according to claim 1, wherein the ratio of the total number of amino groups of the reaction product (A) of the cyclic polyamine compound (a1) and carbon dioxide and the aromatic polyamine compound (C) to the number of isocyanate groups of the polyisocyanate compound (B) in the foamable resin-forming composition (the number of amino groups / the number of isocyanate groups) is 0.5 or more and 1.5 or less.

12. 2. The resin foam-forming composition according to claim 1, wherein the aromatic polyamine compound (C) has a molecular weight of 400 to 1,500.

13. 2. The resin foam-forming composition according to claim 1, wherein the aromatic polyamine compound (C) is a compound represented by the formula (IIIa), in which n is 2 to 6.

14. A polyurea resin foam obtained by foam molding the foamable resin composition according to any one of claims 1 to 13.

15. The polyurea resin foam according to claim 14, comprising a polyurea having a repeating unit represented by the following general formula (I): 【Chemistry 4】 (In formula (I), R 1 is a divalent hydrocarbon group derived from the cyclic polyamine compound (a1) and a divalent organic group derived from the aromatic polyamine compound (C), R 2 is a divalent hydrocarbon group derived from the polyisocyanate compound (B).

16. The polyurea resin foam according to claim 14, wherein the aromatic polyamine compound (C) has an amine value of 100 to 300 mg KOH / g.

17. A method for producing a polyurea resin foam, comprising a step of foaming the resin foam-forming composition according to any one of claims 1 to 13.

18. 18. A method for producing a polyurea-based resin foam according to claim 17, comprising: a step of contacting a cyclic polyamine compound (a1) with a gas containing carbon dioxide to obtain a reactant (A); and a step of mixing the obtained reactant (A) with a polyisocyanate compound (B) and an aromatic polyamine compound (C) to obtain a foam-forming composition.

19. The method for producing a polyurea resin foam according to claim 17, wherein the aromatic polyamine compound (C) has an amine value of 100 to 300 mgKOH / g.

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