JP6995475B2 - Non-yellowing cement-based polyurethane foam composite and its manufacturing method - Google Patents

Description

The present invention relates to a non-yellowing cement-based polyurethane foamed complex. More specifically, the present invention relates to a cement-based polyurethane foamed composite that suppresses yellowing caused by ultraviolet rays and nitrogen oxides and has excellent compression / bending strength as a structural material, a method for producing the same, and its use.

Cement, mortar and concrete (hereinafter sometimes referred to as "cement-based inorganic materials") are relatively inexpensive and versatile materials as basic structural materials in the fields of construction and civil engineering. On the other hand, some composite materials with polyurethane foam have been proposed from the viewpoint of weight reduction and strength development of cement-based inorganic materials. This is because polyurethane foam is lightweight and exhibits high compressive strength. On the other hand, from the viewpoint of polyurethane foam, due to its high price, the mixing ratio with cement-based inorganic materials should be selected as an appropriate value according to the application in consideration of the balance between weight reduction and cost increase. ..

In Patent Document 1, a raw material mixture consisting of cement, modified polypeptide MDI (polymethylene polyphenylene isocyanate), polyol, sand, gravel, and water is placed in a molding mold, cured, demolded after 5 minutes, and cured for another week. Therefore, a composite concrete material having a compressive strength of 1.2 to 1.7 MPa is obtained. However, this modified polymethylene polyphenylene isocyanate is an aromatic ring-based isocyanate, and the cement-based polyurethane foamed composite obtained by using this is affected by ultraviolet rays such as sunlight, and the composite turns yellow over time. There was a problem of discoloration. Further, in Patent Document 1, an aliphatic or alicyclic isocyanate is also described as a polyisocyanate that can be used, but a specific usage thereof is not shown.

As a means for preventing such yellowing, a flexible polyurethane foam having an aliphatic isocyanate or an alicyclic isocyanate using an aliphatic isocyanate instead of an aromatic isocyanate, which is less susceptible to color change, has been proposed. (See, for example, Patent Document 2 and Patent Document 3).
However, it is not intended to mix cement or gravel with this flexible polyurethane foam raw material to obtain a cement-based polyurethane foam composite.

Japanese Unexamined Patent Publication No. 2016-056077 Japanese Unexamined Patent Publication No. 2009-149827 Japanese Unexamined Patent Publication No. 2006-257187

An object of the present invention is to provide a cement-based polyurethane foamed composite having excellent mechanical properties and suppressing yellowing even when left outdoors for a long period of time.

As a result of various studies to solve the above problems, the present inventors, when a specific combination of isocyanate components is used as a raw material component, suppresses yellowing even outdoors for a long period of time and has mechanical properties and mechanical properties. We have found that a cement-based polyurethane foam composite having excellent foam properties can be obtained, and have completed the present invention.

That is, according to the present invention, the following invention is provided.
(1) A cement-based polyurethane foam composite containing a cement-based inorganic filler consisting of cement, cement and sand, or cement and sand and gravel, isocyanate (A), and polyol (B) as raw material components. There,
A cement-based polyurethane foamed composite in which the isocyanate (A) contains an aliphatic isocyanate or a modified product thereof (A1) and an alicyclic isocyanate or a modified product thereof (A2).
(2) The foaming according to (1), wherein the mass ratio of the aliphatic isocyanate or its modified product (A1) to the alicyclic isocyanate or its modified product (A2) is 20:80 to 80:20. Complex.
(3) The foamed complex according to (1) or (2), wherein the aliphatic isocyanate or a modified product thereof (A1) is an isocyanurate modified product of hexamethylene diisocyanate.
(4) The foamed complex according to any one of (1) to (3), wherein the alicyclic isocyanate or the modified product (A2) thereof is isophorone diisocyanate.
(5) The foam according to any one of (1) to (4), wherein the isocyanate (A) has a viscosity at 25 ° C. of 40 to 650 mPa · s and an isocyanate group content of 22 to 35%. Complex.
(6) The foamed complex according to any one of (1) to (5), wherein the polyol (B) contains a polyether polyol having a hydroxyl value of 5 to 300 mgKOH / g and an average number of functional groups of 2 to 6. body.
(7) The foamed composite according to any one of (1) to (6), wherein the mass ratio of the cement-based inorganic filler to the polyurethane resin in the foamed composite is 50:50 to 90:10.
(8) The foaming complex according to any one of (1) to (7), further containing a foam stabilizer, a catalyst and water as raw material components.
(9) The foamed complex according to any one of (1) to (8), wherein the foamed complex has a density of 400 to 800 kg / m ³ .
(10) The foamed complex according to any one of (1) to (9), wherein the compressed strength of the foamed complex is 1.3 to 3.2 MPa.
(11) The foamed complex according to any one of (1) to (10), wherein the foamed complex has a bending strength of 1.5 to 2.7 MPa.
(12) A building material containing the foamed complex according to any one of (1) to (11).
(13) A mixture containing a cement-based inorganic filler consisting of cement, cement and sand, or cement and sand and gravel, isocyanate (A), polyol (B), defoaming agent, catalyst and water. A method for producing a cement-based polyurethane foam composite, which comprises a step of foaming.
A method in which the isocyanate (A) contains an aliphatic isocyanate or a modified product thereof (A1) and an alicyclic isocyanate or a modified product thereof (A2).
(14) The production method according to (13), wherein the time required for injecting the mixture into a mold and removing the mold is within 30 minutes at a mold temperature of 40 to 50 ° C.

According to the present invention, it is possible to provide a cement-based polyurethane foamed composite that is less susceptible to color change such as yellowing even when used outdoors for a long period of time. Further, according to the present invention, it is possible to provide a cement-based polyurethane foam composite having mechanical properties such as density, compressive strength, and bending strength suitable as a cement material. The cement-based polyurethane foam composite of the present invention can be advantageously used in the manufacture of basic structural materials in the fields of construction and civil engineering, outdoor interior decorative walls and blocks, and the like.

The cement-based polyurethane foam composite of the present invention contains a cement-based inorganic filler composed of cement, cement and sand, or cement and sand and gravel, isocyanate (A), and polyol (B) as raw material components. And
The isocyanate (A) contains an aliphatic isocyanate or a modified product thereof (A1) and an alicyclic isocyanate or a modified product thereof (A2).

Hereinafter, the raw material components of the mixture will be described.
The cement-based inorganic filler used in the present invention comprises either cement, cement and sand, or cement and sand and gravel. The cement is not particularly limited, but is the most commonly used Portland cement such as ordinary Portland cement, early-strength Portland cement, ultra-early-strength Portland cement, moderate heat Portland cement, sulfate-resistant Portland cement, and white cement. Other examples include mixed cement such as blast furnace cement, silica cement and fly ash cement, special cement such as alumina cement, ultrafast hard cement, colloid cement and oil well cement, water-hard lime, Roman cement and natural cement. Among these, for example, Portland cements are preferable.

The sand as an aggregate used in the present invention is not particularly limited, but sand that has passed through all 10 mm sieves normally classified as fine aggregate and contains 85% or more by weight of sand having a particle size of 6 mm or less. Point to. Of these, sand for mortar having a particle size of 0.3 to 6 mm is preferable. The mixture of cement and sand with water is the main constituent of so-called mortar. In the cement-based polyurethane foamed composite of the present invention, a foamed composite having good physical property values specified in the present invention can be obtained regardless of whether or not a hydration reaction of cement has occurred.

The amount ratio of cement and sand, that is, the weight ratio of both in the mortar component, may vary depending on the intended use, but may be within the range normally used in mortar products, for example cement: sand = 1: 1.5. It may be in the range of ~ 1: 5, preferably 1: 2 to 1: 4, for example, a 1: 2 weight ratio.

In addition to the above, an admixture (powder such as fly ash, slag powder, silica fume, etc.) usually added to the mortar component can be appropriately added depending on the intended use.

The isocyanate (A) used in the present invention is a combination of an aliphatic isocyanate or a modified product thereof (A1) and an alicyclic isocyanate or a modified product thereof (A2).

The aliphatic isocyanate or a modified product thereof (A1) may be an aliphatic isocyanate having two or more isocyanate groups, a modified isocyanate obtained by modifying them, or a mixture of two or more thereof. Specific examples of the aliphatic isocyanate or a modified product thereof (A1) include isocyanates such as hexamethylene diisocyanate (HMDI), pentamethylene diisocyanate, and lysine diisocyanate and modified products thereof (for example, isocyanurate modified product and urethane modified product). (Urea modified product, Adduct modified product, Biuret modified product, Allophanate modified product, Carbodiimide modified product, etc.) are mentioned, and a hexamethylene diisocyanate (HMDI) isocyanurate modified product is particularly preferable.

The alicyclic isocyanate or a modified product thereof (A2) may be an alicyclic isocyanate having two or more isocyanate groups, a modified isocyanate obtained by modifying them, or a mixture of two or more thereof. Specific examples of the alicyclic isocyanate or its modified product (A2) include isophorone diisocyanate (IPDI), hydrogenated MDI, hydrogenated XDI, norbornan diisocyanate and other isocyanates and modified products thereof (for example, isocyanurate modified product). (Urethane modified product, urea modified product, adduct modified product, biuret modified product, allophanate modified product, carbodiimide modified product, etc.) are mentioned, and isophorone diisocyanate (IPDI) is particularly preferable.

The viscosity of isocyanate (A) obtained by mixing an aliphatic isocyanate or a modified product thereof (A1) and an alicyclic isocyanate or a modified product thereof (A2) at 25 ° C. is preferably 30 to 700 mPa · s. Yes, more preferably 40 to 650 mPa · s. Setting the viscosity of isocyanate (A), which is a combination of two isocyanates, to 30 mPa · s or more means that sand and cement with a large specific density will settle to the bottom of the mold or separate before the urethane foams and hardens. It is preferable to avoid it. Further, setting the viscosity of the isocyanate (A) to 700 mPa · s or less enables efficient stirring with cement and sand, and avoids deterioration of the surface condition of the complex due to the progress of the local urethane reaction. It is advantageous on.

The isocyanate group content of the isocyanate (A) is preferably 22 to 35%, more preferably 25 to 35%. Here, the isocyanate group content can be calculated as the ratio of the theoretical value of the total mass of the isocyanate groups contained in the isocyanate (A) to the total mass of the isocyanate (A).

The mass (A1: A2) of the aliphatic isocyanate or its modified product (A1) and the alicyclic isocyanate or its modified product (A2) is preferably 10:90 to 90:10, more preferably 20. : 80 to 80:20, more preferably 25:75 to 75:25.

The polyol used in the present invention is not particularly limited as long as it does not interfere with the effects of the present invention, but a polyether polyol having a hydroxyl value of 5 to 300 mgKOH / g and an average number of functional groups of 2 to 6 is preferable. The use of such a polyol is particularly advantageous in ensuring the strength of the cement-based polyurethane foamed complex. Here, the average number of functional groups means the number of functional groups per molecule, and can be controlled by the number of functional groups of the initiator. The hydroxyl value is the number of mg of potassium hydroxide required to acetylate the hydroxyl group contained in 1 g of the sample (solid content). Then, the hydroxyl group in the sample is acetylated with acetic anhydride, and the unused acetic acid is titrated with a potassium hydroxide solution, and then it is obtained by the following formula. Hydroxy group value [mgKOH / g] = [((AB) × f × 28.05) / S] + acid value A: Amount (ml) of 0.5 mol / l potassium hydroxide ethanol solution used in the blank test
B: Amount (ml) of 0.5 mol / l potassium hydroxide ethanol solution used for titration
f: Factor S: Sampling amount (g)

As a specific example of the polyether polyol, glycerin is used as a starting material, and a polyether polyol having a functional group number of 3 and a hydroxyl value of about 28 mgKOH / g, which is obtained by ring-opening addition polymerization of alkylene oxide, and propylene glycol are used as starting materials. , A polyether polyol having a hydroxyl value of about 110 mgKOH / g (for example, "Sumiphen 1600U" manufactured by Sumika Cobestlorethane Co., Ltd.), and the number of functional groups, which are obtained by ring-opening addition polymerization of an alkylene oxide. Examples thereof include castor oil, which is a polyester-based polyol having a hydroxyl value of about 160 mgKOH / g and about 2.7.

The mass ratio (cement-based inorganic filler) of the cement-based inorganic filler (consisting of cement, cement and sand, or cement and sand and gravel) and the polyurethane resin (that is, the total of isocyanate and polyol) in the present invention. : Polyurethane resin) may be appropriately determined in consideration of lightness, strength, cost, etc., and suitable ranges include, for example, 50:50 to 95: 5, 55:45 to 85:15, 60:40. ~ 95: 5, 50:50 ~ 90: ~ 10, and the like can be mentioned.

The defoaming agent used in the present invention is an auxiliary agent for forming good bubbles. The bubbles serve as communication holes to prevent the resulting cement-based polyurethane foam complex from shrinking, which contributes to weight reduction and strength development. The defoaming agent is not particularly limited, but for example, a silicone-based defoaming agent (for example, SH-193, L-5420A, SZ1325, SF2937F of Toray Dow Corning, L-580 of Momentive), etc. Examples thereof include B8462) manufactured by Evonik Degusa and a fluorine-containing compound-based defoaming agent.

From the viewpoint of efficient production of the composite, the cement-based polyurethane foam composite of the present invention preferably further contains a defoaming agent, a catalyst and water as raw material components.

The amount of the foam stabilizer is, for example, 1 to 20 parts by mass, preferably 1 to 10 parts by mass, and more preferably 0.5 to 10 parts by mass with respect to 100 parts by mass of the polyether polyol.

The catalyst used in the present invention promotes the urethane forming reaction between isocyanate and polyol. The catalyst is not particularly limited as long as it promotes the urethane formation reaction, and is preferably an amine catalyst (hexahydro-S-triazine, triethylenediamine, triethylamine, bis (2-dimethylaminoethyl) ether, etc. N, N-dimethylcyclohexylamine (Polycat 8), imidazole compound, N, N, N-tris (dimethylaminopropyl), etc.), temperature-sensitive catalyst (1,8-diazabicyclo [5.4.0] undecene-7 (DBU) and its organic acid salt), a metal catalyst (di-n-butyltin dilaurate (DBTDL)) or a combination thereof.

The amount of the catalyst can be, for example, 0.1 to 5 parts by mass, preferably 1 to 3 parts by mass with respect to 100 parts by mass of isocyanate.

The water used in the present invention can be used as a medium for dispersing raw materials to form a slurry, and at the same time, a part of the water can be advantageously used for reacting with an isocyanate group to generate carbon dioxide gas to form foam. can.

The amount of water is not particularly limited as long as the amount of water is sufficient to stir and mix the water and the cement-based inorganic filler to obtain a slurry state. The amount of water may be appropriately set by those skilled in the art in consideration of the amount required for the hydration reaction of the cement and the reaction of all the isocyanates used, but it is usually necessary to obtain a good slurry state. The amount of water is much larger than the amount of water required for the reaction. The mass ratio of the cement-based inorganic filler and water at the time of specific mixing is, for example, 5 to 45 parts by mass, preferably 10 to 30 parts by mass of water with respect to 100 parts by mass of the cement-based inorganic filler. Can be.

In the cement-based polyurethane foam composite of the present invention, the density and strength (compressive strength, bending strength, etc.) according to the use of the foam composite can be imparted by appropriately adjusting the amount and ratio of the raw material components. The density, compressive strength, and bending strength of the foamed composite of the present invention can be measured according to JIS K 7222 (2005), K 7220 (2006), and K 7221-2 (2006), respectively.

The density of the foamed complex of the present invention is, for example, 300 to 900 kg / m ³ , preferably 400 to 800 kg / m ³ , and more preferably 400 to 700 kg / m ³ . Adjusting the density of the cement-based polyurethane foam complex within the above range is particularly preferable in terms of weight reduction.

The compressive strength of the foamed complex of the present invention is, for example, 1.3 to 3.2 MPa, more preferably 1.6 to 3.0 MPa.

The bending strength of the foamed complex of the present invention is, for example, 1.5 to 2.7 MPa, more preferably 1.6 to 2.5 MPa.

Further, as described above, the foamed complex of the present invention has excellent weather resistance stability. Therefore, for example, even after outdoor exposure for 12 months, the foamed complex of the present invention can effectively prevent the change in color tone due to surface cracking and yellowing. The presence or absence of weather resistance in the present invention can be determined by the method of Test Example 3 described later.

Next, the manufacturing method of the present invention will be described. As described above, the cement-based polyurethane foamed composite of the present invention can be easily produced by foaming a mixture of the above raw material components. Therefore, the production method of the present invention is a cement-based inorganic filler composed of either cement, cement and sand, or cement and sand and gravel, isocyanate (A), polyol (B), foam stabilizer, catalyst and water. The isocyanate (A) contains an aliphatic isocyanate or a modified product thereof (A1) and an alicyclic isocyanate or a modified product thereof (A2). Will be done.

The mixture of raw material components in the production method of the present invention comprises a cement-based inorganic filler (consisting of cement, cement and sand, or cement and sand and gravel), isocyanate (A), polyol, defoaming agent, and catalyst. And water may be added in any order, stirred and mixed to prepare. However, since the reaction starts immediately when the isocyanate comes into contact with the polyol and / or water in the presence of a catalyst, it is preferable in the manufacturing process that isocyanate is added last to form a mixture. More specifically, an isocyanate (A) and a composition containing other raw material components are prepared (so-called "two-component reaction type composition"), and then the composition and the isocyanate (A) are mixed. It is preferable to do so. Further, from the viewpoint of avoiding the start of the reaction, the catalyst may be added at the end after mixing and stirring other raw material components other than the catalyst.

Mixing and stirring of the raw material components may be performed directly in the mold (mold) used in the subsequent molding process, but since the mold is usually a square shape, it is circular in consideration of mixing efficiency. Add raw material components to a cup (eg, polycup for small experiments, polymer liner circular stirrer for large scale production, etc.) and mixer (eg, hand mixer for small scale experiments, large scale). In the production, it is preferable to immediately transfer the mixture to the mold after stirring and mixing with an electric stirrer or the like). As described above, since the urethanization reaction starts immediately with the addition of isocyanate or catalyst, it is preferable to add other raw material components in advance and sufficiently stir and mix to form a slurry before adding them. Since the reaction starts immediately after the start of stirring for adding the isocyanate or the catalyst, it is preferable to stop the stirring in the circular cup for a short time (for example, for several seconds) and immediately cast the mixture. At this time, high-speed stirring is preferable from the viewpoint of obtaining sufficient mixing efficiency by stirring for a short time.

The surface condition in the cup can be visually observed and finger eroded to be used as a guideline for the progress of the curing (polymerization and cross-linking) reaction. More specifically, the period until the mixture of the raw material components is cured (gel time) can be used as an index.

Further, in the production method of the present invention, the cement-based polyurethane foamed composite of the present invention may be prepared into a desired shape by injecting a mixture of raw material components into a mold. The initial temperature setting of the mold is not particularly limited as long as it does not interfere with the production of the foamed composite of the present invention, but may be about room temperature (about 40 ° C. to 50 ° C.). Here, since the formation of the foamed complex is accompanied by the generation of heat of polymerization for polyurethane formation along with the foaming, the temperature inside the mold may also rise. Therefore, the temperature inside the mold may rise, for example, by about 30 to 40 ° C. during the reaction. In addition, the pressure inside the mold may increase slightly with foaming, and such an increase in pressure may be, for example, about 0.5 MPa.

Further, as described above, the foam complex of the present invention can effectively avoid color change such as yellowing even when used outdoors for a long period of time, and thus can be used as a building material for outdoor interior decorative walls and blocks. It can be suitably used. Therefore, according to a preferred embodiment, a building material containing the foamed complex of the present invention is provided. Further, according to another aspect, the use of the foamed composite of the present invention in the production of building materials is provided. Further, in any of the above embodiments, the building material is a decorative wall material or a block.

Hereinafter, examples of the present invention will be described in detail, but the scope of the present invention is not limited to these examples.

Test Example 1
<Manufacturing of cement-polyurethane foam composite 1>
[Example 1]
In a polycup (diameter 8 cm) with a capacity of 500 ml, 50 g of Portoland cement, 100 g of sand, 30 g of water, and 8 of polyol B (Sumiphen 1600U manufactured by Sumika Cobestrourethane; number of functional groups 2, hydroxyl value 110 mgKOH / g). .8 g, foam stabilizer (Toray Dow Corning Silicone SH-193) 0.42 g, amine catalyst C1 (Air Products Polycat 8) 0.5 g, amine catalyst C2 (Air Products DABCO 33LV) 1 0.0 g, 0.3 g of the temperature-sensitive catalyst C3DBU (San Apro) and 1.0 g of the metal catalyst C4 (DBTDL) were added, and the mixture was stirred with a hand mixer at 4,500 rpm for 7 seconds to obtain a uniform slurry. Next, 75 g of isocyanate A1 (Sumidur N3300 manufactured by Sumika Covestro) and 25 g of isocyanate A2 (Desmodur I manufactured by Covestro) were added, and the mixture was stirred with a hand mixer at 4,500 rpm for 7 seconds, foamed, and at room temperature until cured. A cement-based polyurethane foamed composite was obtained.

[Examples 2 and 3 and Comparative Examples 1 and 2]
Examples 2 and 3 and Comparative Examples 1 and 2 were produced by the same method as in Example 1 except that the amount of the polyol added and the types of isocyanate A1 and isocyanate A2 were changed as shown in Table 1.

<Physical characteristics evaluation of cement-based polyurethane foam complex 1>
As described below, the cement-based polyurethane foam composites of Examples 1 to 3 and Comparative Examples 1 and 2 were evaluated.

[Gel time]
The time point at which isocyanate A1 and isocyanate A2 are added and mixing is started is set to zero seconds, and the period until the mixed solution is cured (even if the surface of the foam is pierced with disposable chopsticks, the inside is cured and cannot be pierced). Time to become) was measured (unit: seconds).

[Effervescent]
When the density and compressive strength of the cement-based polyurethane foam composite of Example 1 were measured by the method described later, they showed ideal values of a density of about 600 kg / m ³ and a compressive strength of about 2 MPa. Therefore, in order to confirm the physical characteristics that are the prerequisites for producing a foamed complex having such ideal physical properties, the height of the cement-polyurethane foamed composite of Example 1 contained in the polycup at the gel time was set. Criteria (A) were used, those higher than this were used as (B), and those lower than this were used as (C).

[Brigidity]
The brittleness of the cement-based polyurethane foam complex in gel time was manually evaluated by a panelist (healthy adult male) trained according to the following criteria.
A: Cannot be pierced even with disposable chopsticks (similar brittleness as in Example 1)
B: The cement-based polyurethane foam composite breaks when you try to stab it with disposable chopsticks.

The results were as shown in Table 1. In the comprehensive evaluation, "○" was given when both foamability and brittleness were A, and "x" was given in other cases.

Test Example 2
<Manufacturing of cement-polyurethane foam composite 2>
[Example 4]
150 g of Portoland cement, 300 g of sand, 75 g of water, and 30 g of polyol B (Sumiphen 1600U manufactured by Sumika Cobestrourethane Co., Ltd .; number of functional groups 2, hydroxyl value 110 mgKOH / g) in a polycup having a capacity of 1000 ml. 1.26 g of foam stabilizer (Toray Dow Corning's silicone SH-193), 1.5 g of amine catalyst C1 (Polycat8 of Air Products), 3.0 g of amine catalyst C2 (DABCO33LV of Air Products), 0.9 g of the temperature-sensitive catalyst C3DBU (San-Apro) and 3.0 g of the metal catalyst C4 (DBTDL) were added, and the mixture was stirred with a hand mixer at 4,500 rpm for 7 seconds to obtain a uniform slurry. Next, 156 g of isocyanate A1 (Sumidur N3300 manufactured by Sumika Covestro) and 144 g of isocyanate A2 (Desmodur I manufactured by Covestro) were added, and the mixture was stirred with a hand mixer at 4,000 rpm for 7 seconds, and then a mold at 40 ° C. (vertical). : 210 mm × width: 210 mm × height: 25 mm), and the mold was removed 30 minutes after the start of stirring to obtain a cement-based polyurethane foam composite.

[Examples 5 to 7]
Examples 5 to 7 were produced by the same method as in Example 4 except that the amounts of isocyanate A1 and isocyanate A2 were changed as shown in Table 1.

<Physical property evaluation 2 of cement-based polyurethane foam composite>
One week after obtaining the cement-based polyurethane foam composite, the density, compressive strength, and bending strength were evaluated according to the following methods.

[Density, compressive strength and bending strength]
Density, compressive strength and bending strength were measured according to JIS K 7222 (2005), K 7220 (2006) and K 7221-2 (2006), respectively.

The results were as shown in Table 1.

When only one of the aliphatic isocyanate A1 and the alicyclic isocyanate A2 is used in Test Example 1, both the foamability and brittleness of the cement-based polyurethane foam composite can be satisfied. There wasn't.
On the other hand, when both the aliphatic isocyanate A1 and the alicyclic isocyanate A2 were used, the foamability and brittleness of the cement-based polyurethane foamed composite were both good.
Further, in Test Example 2, as a result of producing the cement-based polyurethane foam composites of Examples 5 to 7 using both the aliphatic isocyanate A1 and the alicyclic isocyanate A2, their densities were about 600 kg / m ³ . The compressive strength was 1.6 to 3.0 MPa and the bending strength was 1.6 to 2.5 MP, showing appropriate values as a cement material.

Test Example 3
<Evaluation of weathering stability of cement-based polyurethane foam composite>
The cement-based polyurethane foam composite of Example 5 was allowed to stand outdoors in a place exposed to direct sunlight, and the change in appearance after 12 months was trained by panelists (10 persons) according to the following criteria. evaluated. Here, when the majority of specialized panelists evaluate A, the overall evaluation result is also determined to be A.
A: There are no cracks on the surface and no change in color tone (yellowing) has occurred. B: There are cracks on the surface or change in color tone (yellowing).

As a result of the test, the evaluation result of all the specialized panelists was A. It was confirmed that the cement-based polyurethane foam composite of the present invention has good weather resistance stability.

The cement-based polyurethane foam composite of the present invention can be imparted with a cement material and suitable physical properties. Further, according to the cement-based polyurethane foamed composite of the present invention, it is possible to effectively avoid the change in color tone even when used outdoors for a long period of time. The cement-based polyurethane foam composite of the present invention can be advantageously used as a building material such as a decorative wall material and a block.

Claims (13)

Cement-based polyurethane foam containing cement, cement-based inorganic filler consisting of cement and cement and sand, or cement and sand and gravel, isocyanate (A) having two or more isocyanate groups , and polyol (B) as raw material components. It ’s a complex,
The isocyanate (A) contains an aliphatic isocyanate having two or more isocyanate groups or a modified product thereof (A1) and an alicyclic isocyanate having two or more isocyanate groups or a modified product thereof (A2), and is an aliphatic product. A cement-based polyurethane foamed composite in which the mass ratio of the isocyanate or a modified product thereof (A1) to the alicyclic isocyanate or a modified product thereof (A2) is 20:80 to 80:20. The foamed complex according to claim 1, wherein the aliphatic isocyanate or a modified product thereof (A1) is hexamethylene diisocyanate or a modified product thereof. The foamed complex according to claim 1 or 2, wherein the alicyclic isocyanate or a modified product thereof (A2) is isophorone diisocyanate or a modified product thereof. The foamed complex according to any one of claims 1 to 3, wherein the isocyanate (A) has a viscosity at 25 ° C. of 40 to 650 mPa · s and an isocyanate group content of 22 to 35%. .. The foamed composite according to any one of claims 1 to 4, wherein the polyol (B) contains a polyether polyol having a hydroxyl value of 5 to 300 mgKOH / g and an average number of functional groups of 2 to 6. The foamed composite according to any one of claims 1 to 5, wherein the mass ratio of the cement-based inorganic filler to the polyurethane resin in the foamed composite is 50:50 to 90:10. The foaming complex according to any one of claims 1 to 6, further containing a foam stabilizer, a catalyst and water as raw material components. The foamed complex according to any one of claims 1 to 7, wherein the density of the foamed complex is 400 to 800 kg / m ³ . The foamed complex according to any one of claims 1 to 8, wherein the compressed strength of the foamed complex is 1.3 to 3.2 MPa. The foamed complex according to any one of claims 1 to 9, wherein the foamed complex has a bending strength of 1.5 to 2.7 MPa. A building material containing the foamed complex according to any one of claims 1 to 10. Contains cement-based inorganic filler consisting of cement, cement and sand, or cement and sand and gravel, isocyanate (A) having two or more isocyanate groups , polyol (B), defoaming agent, catalyst and water. A method for producing a cement-based polyurethane foam composite, which comprises a step of foaming the mixture.
The isocyanate (A) contains an aliphatic isocyanate having two or more isocyanate groups or a modified product thereof (A1) and an alicyclic isocyanate having two or more isocyanate groups or a modified product thereof (A2), and is an aliphatic product. A method in which the mass ratio of the isocyanate or a modified product thereof (A1) to the alicyclic isocyanate or a modified product thereof (A2) is 20:80 to 80:20. The production method according to claim 12, wherein the time required for injecting the mixture into a mold and removing the mold is within 30 minutes at a mold temperature of 40 to 50 ° C.