JP2016056077A - Cement-based polyurethane foamed composite and method for producing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To produce, from a viewpoint of weight reduction and strength development of a cement-based inorganic material, a composite material having both low density and strength in a short demolding time.SOLUTION: The cement-based polyurethane foamed composite is obtained by foaming a mixture comprising: a cement-based inorganic filler composed of any of cement, cement and sand, or cement and sand and gravel; a polyisocyanate; a polyol; a foam stabilizer; a catalyst; and water. The polyol is a polyether polyol having a hydroxyl value of 5 to 300 mg KOH/g, and a number of functional groups of 2 to 6. The polyol preferably does not dissolve in a water solubility test and/or has an HLB value according to the Davies' method of 11 or less.SELECTED DRAWING: None

Description

  The present invention relates to a cement-based polyurethane foam composite. More particularly, the present invention relates to a cement-based polyurethane foam composite as a material having excellent compressive strength as a structural material, a molded foam can be obtained in a short demolding time, and having a cost advantage, a manufacturing method thereof, and an application thereof.

  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 architecture and civil engineering. On the other hand, several composite materials with foamed polyurethane have been proposed from the viewpoint of weight reduction and strength development of cement-based inorganic materials. This is because foamed polyurethane 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 to the cement-based inorganic material should be selected in accordance with the balance between weight reduction and cost increase. .

In Patent Document 1, a raw material composition comprising 100 parts by weight of cement, 6 parts by weight of polyisocyanate, 0.6 parts by weight of polyol, 120 parts by weight of sand, 180 parts by weight of gravel, and 60 parts by weight of water is put into a molding machine and condensed. 72 hours later, and further cured for 28 days to obtain a composite concrete material having a compressive strength of 160 to 300 kg / cm ² (16 to 30 MPa). However, since it is a concrete containing a large amount of gravel for high strength, the polyurethane part occupies only 1.4% by weight in the entire molded product, and is a composition far from being reduced in weight.

In Patent Document 2, 250 parts by weight of Portland cement, 290 parts by weight of water, and 100 parts by weight of a urethane raw material composition (an equimolar mixture of diphenylmethane diisocyanate and polypropylene glycol) are mixed and filled into a mold, The mixture is cured and completely cured to obtain a cement-based polyurethane composite having a compressive strength of 10 kgf / cm ² (1 MPa) or more (the same document, Example 3). Here, according to the description in paragraph 0024 of the document, “If the mixture obtained by mixing a predetermined amount of the cement slurry and the urethane raw material composition is filled in the mold, the moisture of the cement slurry, While the urethane raw material composition is foam-cured, the hydraulic cement is also cured by hydration, and the urethane raw material composition and the hydraulic cement can be cured integrally. The foamed polyurethane is obtained in about 10 to 30 minutes, while the hardening of the hydraulic cement starts almost simultaneously, but the curing period until the hardening is completed is usually about 20 to 40 days. As a structural material used in a scene where long-term curing is required and strength in short-term construction is required to obtain the desired compressive strength. It is not suitable.

In patent documents 3 and 4, 300 g of urethane-based hardener main agent (polyisocyanate group prepolymer), 15 g of urethane-based hardener auxiliary agent (polyol and catalyst), blast furnace cement B type (silica-based blast furnace slag 30 to 60% or less A mixture containing 600 g of Portland cement and gypsum and mixed and pulverized) and 240 to 360 g of water are mixed to form a slurry, which is then cured to form a foamable solid. The curing start time is 1 to 3 minutes, reaches 76 to 78 ° C. due to heat generation during curing, and the compressive strength after curing for one day is 69.4 to 29.0 kgf / cm ² (6.9 to 2.9 MPa). And high strength are achieved (Examples 1 and Nos. 11 to 13 in Documents 3 and 4). This high strength is considered to be derived from the high content of the urethane-based curing agent (Example No. 1 in References 3 and 4 is 71.4 kgf / cm ² (7.1 MPa as a control value without cement mixing). ) Shows high strength.). The composition ratio of urethane / blast furnace cement B in this composition is 315/600, that is, a high urethane composition of about 34/66, which is an unsatisfactory composition in consideration of economy. In addition, this high strength is a value after one day of curing, and must be said to be insufficient in terms of time cycle when considering a continuous production line.

On the other hand, Letizia Verdolotti et al. (Non-patent Document 1) mixed cement powder and polyol, catalyst, silicone surfactant, crosslinker and water as a foaming agent at room temperature, and stirred for 2 minutes before diisocyanate (diphenylmethane diisocyanate (MDI)). ) To obtain a polyurethane / cement foam composition (polymer cement) with a constant ratio of urethane to cement of 2/3. The composition was stirred for 40 seconds, filled into a 50 × 50 × 5 cm ³ wooden mold, and solidified at room temperature for 20 minutes. The molded product was hydrated in water at 60 ° C. for 72 hours. The compressive strengths of the hydrated polymer cement (“HIRP-C”) and the non-hydrated polymer cement (“PC”) were 4.31 MPa and 3.4 Mpa, respectively. However, the solidification time (corresponding to the demolding time) is as long as 20 minutes, and further improvement is required in terms of efficiency of the production line.

  As described above, various composite materials with foamed polyurethane prepolymers have been proposed from the viewpoint of weight reduction and strength development of cement-based inorganic materials, but short demolding of composite materials having the desired low density and strength has been proposed. Getting in time has not been achieved yet.

Japanese Patent Publication No. 50-6213 JP 2002-38619 A Japanese Patent Laid-Open No. 06-80483 Japanese Patent Laid-Open No. 06-80966

Letizia Verdolotti et al. “J.Mater.Sci. (2012) 47: 6948-6957”

  An object of the present invention is to solve various problems of the prior art. That is, the present invention achieves low density and high compressive strength within a short demolding time in a cement-based polyurethane foam composite, resulting in a composite material that can be applied in various fields. At the same time, it will also achieve cost advantage.

  The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a cement-based polyurethane foam composite having a desired density and strength in a short demolding time.

  The present invention made to achieve the above object is to foam a mixture containing a cement-based inorganic filler consisting of cement, cement and sand, or cement and sand and gravel, polyisocyanate, polyol and the like. The obtained cement-based polyurethane foam composite, which comprises a predetermined polyol component, a method for producing the foam composite, and uses thereof are provided. Specifically, the present invention is shown below.

<1> The present invention foams a mixture comprising a cement-based inorganic filler consisting of cement, cement and sand, or cement and sand and gravel, polyisocyanate, polyol, foam stabilizer, catalyst and water. In the cement-based polyurethane foam composite obtained by
The polyol is a cement-based polyurethane foam composite containing a polyether polyol having a hydroxyl value of 5 to 300 mgKOH / g and a functional group number of 2 to 6.

  <2> The foamed composite according to <1>, wherein the polyol is a polyether polyol that does not dissolve in a water solubility test and / or has a Davis method HLB value of 11 or less.

<3> In the present invention, the ratio of the cement-based inorganic filler and the polyurethane resin of the foam composite is 50:50 to 90:10, and the foam composite density is 400 to 800 Kg / m ^3. It is a foam composite as described in 1> or <2>.

  <4> The present invention is as described in any one of <1> to <3>, wherein the time until the mixture is poured into the mold and demolded is 5 minutes or less at a mold temperature of 30 to 40 ° C. Foam composite.

  <5> The foamed composite according to any one of <1> to <4>, wherein the polyisocyanate is polymethylene polyphenylene polyisocyanate (sometimes referred to as polymeric MDI) or a modified product thereof. It is.

<6> The present invention is a mixture of a cement-based inorganic filler consisting of cement, cement and sand, or cement and sand and gravel, polyisocyanate, polyol, foam stabilizer, catalyst and water. A method of producing a cement-based polyurethane foam composite by stirring and foaming,
The polyol is a method for producing a foamed composite containing a polyether polyol having a hydroxyl value of 5 to 300 mgKOH / g and a functional group number of 2 to 6.

  <7> The present invention is the method for producing a foamed composite according to <6>, wherein the polyol is a polyether polyol that does not dissolve in a water solubility test and / or has a Davis method HLB value of 11 or less. .

  <8> The present invention is a structural material comprising the foamed composite according to any one of <1> to <5>.

<9> The present invention has a high strength at the time of demolding (compressive strength is 1.0 to 1.8 MPa), light weight (specific gravity is 400 to 800 kg / m ³ ), and heat insulation or heat retention (thermal conductivity is 0). 0.07 to 0.10 W / mK), the structural material according to <8>.

  <10> The present invention is the structural material according to <8> or <9>, which is used as a heat insulating material or a heat insulating material.

  According to the present invention, it was possible to develop a cement-based polyurethane foam composite having a high strength at the time of demolding, light weight, and heat insulation or heat retention in a short demolding time. As a result, it was possible to achieve a reduction in weight and strength of a cement-based inorganic material, which is a relatively inexpensive and versatile material as a basic structural material in the field of construction and civil engineering. On the other hand, when viewed from the side of the polyurethane foam which is lightweight and exhibits high compressive strength, the cost reduction can be achieved. The cement-based polyurethane foam composite thus obtained can be used in many ways as a heat-insulating material or a heat insulating material as a foamed composite material having various performance and cost balance.

  Hereinafter, although the form for implementing this invention is demonstrated in detail, the scope of the present invention is not limited to these forms.

  The cement-based polyurethane foam composite of the present invention comprises a cement-based inorganic filler composed of any one of cement, cement and sand, or cement and sand and gravel, polyisocyanate, the polyol according to the present invention, a foam stabilizer, a catalyst, and It can be produced by foaming a mixture comprising water.

  Although there is no particular limitation on the mixing order of each component in the mixture, a urethane forming reaction (including a urethanization reaction, a ureation reaction, a biuret binding reaction, etc.) starts when the polyisocyanate comes into contact with the polyol. Usually, it is preferable that the mixing order is such that the contact between the two is performed in the final mixing process. This is a so-called “two-component reaction type composition”.

  That is, a cement-based inorganic filler composed of any one of cement, cement and sand, or cement, sand and gravel in a mold for molding a foamed composite (sometimes referred to as “mold”), polyol, foam stabilizer Then, a catalyst and water are mixed and stirred to form a slurry, and polyisocyanate (and / or a prepolymer modified product thereof) is added and mixed in the slurry, and the polyisocyanate and water in the slurry are mixed. The polyisocyanate and the polyol are polymerized while being foamed by the carbon dioxide gas generated by the reaction with the above, and any of cement, cement and sand, or cement and sand and gravel in the slurry is formed in the polyurethane formed by the polymerization. A foam composite in which a cementitious inorganic filler powder composed of the above is dispersed is formed.

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

  The sand as aggregate used in the present invention is not particularly limited, but sand that passes through all 10 mm sieves usually classified as fine aggregate and contains 85% or more by weight of particles having a particle diameter of 6 mm or less. Point to. Among them, mortar sand having a particle size of 0.3 to 6 mm is preferable. A mixture obtained by adding water to the cement and sand is a main component of so-called mortar. In the cement-based polyurethane foam composite of the present invention, a foam composite having good predetermined physical property values of the present invention can be obtained regardless of whether or not a cement hydration reaction occurs.

  The amount ratio of cement and sand, that is, the weight ratio of both in the mortar component may vary depending on the application to be used, but may be in a range usually 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 1: 3 weight ratio.

  In addition to the above, admixtures normally added to the mortar component (powder such as fly ash, slag powder, silica fume, etc.) can be appropriately added depending on the application.

  Gravel as an aggregate used in the present invention is not particularly limited, but gravel preferably containing 85% or more by weight of a particle size of 5 mm or more, which is usually classified as a coarse aggregate. The mixture of cement, sand and gravel with water is the main component of so-called concrete. In the cement-based polyurethane foam composite of the present invention, the predetermined good foam composite of the present invention can be obtained regardless of the occurrence of cement hydration reaction.

  The amount ratio of cement, sand and gravel, that is, the weight ratio of these three components in the concrete component may vary depending on the application used, but may be in the range normally used in concrete products, for example, cement: sand: Gravel = 1: 0.5-3: 0.5-4, preferably 1: 1-2: 1.5-3.5, for example 1: 2: 3 weight ratio.

  In addition to the above, admixtures (powder such as fly ash, slag powder, silica fume, etc.) that are usually added to concrete components can be appropriately added depending on the application.

  The polyisocyanate used in the present invention is not particularly limited, but an aromatic, alicyclic, or aliphatic polyisocyanate having two or more isocyanate groups, a mixture of two or more thereof, and a mixture thereof. There are modified polyisocyanates obtained by modification. Specifically, for example, tolylene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), polymethylene polyphenyl polyisocyanate (common name: also called polymeric MDI or crude MDI), xylylene diisocyanate (XDI), isophorone diisocyanate (IPDI) And polyisocyanates such as hexamethylene diisocyanate (HMDI) and modified products thereof, such as isocyanurate-modified products, urethane-modified products, urea-modified products, adduct-modified products, biuret-modified products, allophanate-modified products, and carbodiimide-modified products. It is done. Among these, polymeric MDI, urethane-modified MDI and / or urethane-modified polymeric MDI obtained by urethanation reaction of MDI and / or polymeric MDI are particularly preferable.

  The polyol used in the present invention reacts with isocyanate to form polyurethane, and at the same time, acts as a cross-linking agent depending on the functionality of the polyol, affecting the strength of the resulting cementitious polyurethane foam composite.

  The polyol used in the present invention is not particularly limited as long as it is a polyol that satisfies the predetermined requirements of the present invention. The predetermined requirement of the present invention is that the polyol is a polyether polyol having a hydroxyl value of 5 to 300 mgKOH / g and a functional group number of 2 to 6. More preferably, the polyether polyol satisfies the requirement that it does not dissolve in the water solubility test and / or the HLB value by Davis method is 11 or less.

  The water solubility test referred to here is a test method in which polyol and water are mixed and stirred in a test tube under the condition of water / polyol = 6/1 weight ratio, and the state after standing for one day is visually confirmed. It is. As a result of visual inspection, the case of “white turbidity or layer separation” is evaluated as “not dissolved”. On the other hand, the dissolution in the water dissolution test is evaluated as “dissolve” when the state after standing for one day is “transparent or slightly cloudy”.

  The Davis method HLB value here refers to the number of groups determined by the type of functional group (for example, the number of both lipophilic group methyl group and methylene chain group is -0.475, hydrophilic group ethyleneoxy group or hydroxyl group). The radix of 0.33 and 1.9 (see Table 1) are the values calculated by Equation 1 (Xiaowen Guo, Zongming Rong, Xugen Ying, “Calculation of hydrophile-lipophile balance for polyethoxylated surfactants by group contribution method ”Journal of Colloid and Interface Science 298 (2006) 441-450).

    HLB value = 7 + total number of hydrophilic group groups−total number of lipophilic group numbers (Formula 1).

  The Davis method HLB value indicates the degree of relative hydrophilicity-lipophilicity, and the higher the value, the stronger the hydrophilicity level, and the smaller the value, the stronger the lipophilicity level. In the present invention, the HLB value may be 11 or less, preferably 0 to 11, more preferably 5 to 11, for example 7 to 11.

  One of the major features of the present invention is that polyols that meet the above criteria give high compressive strength in a short demolding time. This feature of the present invention does not depend on the reason for its origin, but the present inventors consider the reason as follows. That is, if the water solubility of the polyol is high, the polyol is dissolved in a large amount of water, and the reaction between the polyol and the isocyanate is hindered, so that there is a problem in moldability (demoldability) in a short time. Will occur. On the other hand, if the water solubility of the polyol is low, the reaction between the polyol and the isocyanate proceeds smoothly, and the moldability (demoldability) in a short time is considered to be good. In addition, under the conditions where no polyol is present, the moldability (demoldability) is still poor (Comparative Example 5 described later), so it can be understood that it is important that the polyol is effectively involved in this reaction.

  As the polyether polyol satisfying the above criteria, for example, a polyether polyol having a functional group number of 3 and a hydroxyl value of about 28 mgKOH / g obtained by ring-opening addition polymerization of alkylene oxide using glycerin as a starting material (for example, Sumika) “SBU polyol 0248” from Bayer Urethane Co., Ltd. Davis method HLB value = 10), obtained by subjecting propylene glycol as a starting material to ring-opening addition polymerization of alkylene oxide, and having a functional group number of 2 and a hydroxyl value of about 110 mg KOH / polyether polyol (for example, “Sumiphen 1600U” manufactured by Sumika Bayer Urethane Co., Ltd., Davis method HLB value = 9.5), and polyester-based polyol having a functional group number of about 2.7 and a hydroxyl value of about 160 mgKOH / g Castor oil (Davis method HLB value = 7. ) And the like, but not limited thereto.

  When a polyol that does not satisfy any of the above criteria is used, a cement-based polyurethane foam composite having the prescribed performance of the present invention cannot be obtained. That is, the stickiness remains at the time of the predetermined short-time demolding of the present invention, the hardness becomes insufficient, and a sufficient compressive strength cannot be obtained.

  The weight ratio of cement-based inorganic filler (consisting of cement, cement and sand, or cement and sand and gravel) and polyurethane resin (ie, polyisocyanate + polyol) in the present invention is the cement-based polyurethane obtained. It is one of the most basic composition ratios that determines the properties of the foam composite. If the amount of the cement-based inorganic filler component is too large, it may be unsatisfactory in terms of functions such as weight reduction and strength. On the other hand, if the amount of the polyurethane component is excessive, it may be unsatisfactory in terms of cost. A desired mixing ratio can be selected while taking them into consideration, but the ratio of cement-based inorganic filler: polyurethane (weight ratio) is usually 40:60 to 95: 5, preferably 50:50 to 90: 10, particularly preferably 55:45 to 85:15, for example 80:20 or 60:40.

  The foam stabilizer used in the present invention is an auxiliary agent for forming good bubbles. The bubbles serve as communication holes and prevent reduction of the resulting cement-based polyurethane foam composite, contributing to weight reduction and strength development. The foam stabilizer is not particularly limited. For example, a silicone foam stabilizer (for example, SH-193, L-5420A, SZ1325, SF2937F of Toray Dow Corning, L-580 of Momentive, Evonik Degussa B8462) and fluorine-containing compound-based foam stabilizers. The amount of foam stabilizer may be up to 20 parts by weight, in particular 1 to 10 parts by weight, for example 0.5 parts by weight, per 100 parts by weight of polyether polyol.

The density of the cement-based polyurethane foam composite of the present invention depends on the ratio and foaming ratio of polyurethane and cement-based inorganic filler (consisting of either cement, cement and sand, or cement, sand and gravel). The density of the foamed composite of the present invention is usually 300 to 900 Kg / m ³ , preferably 400 to 800 Kg / m ³ , for example, 400 to 700 Kg / m ³ , thereby achieving weight reduction.

  The catalyst used in the present invention accelerates the urethane forming reaction between polyisocyanate and polyol. The catalyst is not particularly limited as long as it accelerates the urethane formation reaction, but triethylenediamine, triethylamine, bis (2-dimethylaminoethyl) ether, imidazole compound, 1,8-diazabicyclo [5]. 4.0] undecene-7 and its organic acid salt, and N, N, N-tris (dimethylaminopropyl) hexahydro-S-triazine. Among these, for example, tertiary amines such as Aircat's Polycat 8 are preferred as the catalyst.

  The amount of catalyst may be 0.01-5% equivalent, preferably 0.1-1% equivalent, for example 0.5% equivalent, relative to 1 equivalent of isocyanate groups.

  Water used in the present invention is used as a medium for forming a slurry by dispersing raw materials, and at the same time, a part of the water is an essential component for reacting with an isocyanate group to generate carbon dioxide to form foam.

  The amount of water is not particularly limited as long as there is a sufficient amount for stirring and mixing water and the cement-based inorganic filler to form a slurry state. The amount of water is required to include the amount necessary for foaming by reacting with the hydration reaction of the cement and the polyisocyanate group to be used. The amount is very large compared to the amount of water required for the reaction.

  In order to reduce the density of the cement-based polyurethane foam composite of the present invention, it is necessary to use carbon dioxide gas generated by the reaction of polyisocyanate with water as a foaming source. On the other hand, only the polyisocyanate without a polyol had a problem in moldability as shown in Comparative Example 5. For the improvement, in the present invention, in evaluating the effect of adding various polyols, the inventors have found that a specific polyol exhibits a sufficient compressive strength in a short demolding time. In this examination process, first, the ratio of polyol: polyisocyanate was set to 1: 9 (weight ratio). Although it has been considered to increase the polyol ratio, the reaction between the polyol and the polyisocyanate takes precedence, and the amount of carbon dioxide generated by the reaction between water and the polyisocyanate decreases, which is not preferable. Therefore, in the present invention, the evaluation of other components was performed using a polyol: polyisocyanate ratio = 1: 9 (weight ratio) as a standard.

  Subsequently, when the ratio of polyol: polyisocyanate was changed and examined, if this ratio is between 5:95 and 70:30, preferably between 10:90 and 60:40, the predetermined performance of the present invention is exhibited. (See Examples 1 to 3). It was a great surprise that the polyol component specified in the present invention greatly improved the moldability even though its blending amount was slight.

  Next, the manufacturing method of this invention is demonstrated. The production method of the present invention includes a cement-based inorganic filler (comprising any one of cement, cement and sand, or cement and sand and gravel), a polyisocyanate, a polyol, a foam stabilizer, a catalyst, and water. In which the polyol is a polyether polyol having a hydroxyl value of 5 to 300 (mgKOH / g) and having 2 to 6 functional groups. It is a manufacturing method of a foam composite characterized by containing.

  More preferably, the production method of the present invention is a production method of a foamed composite in which the polyol is a polyether polyol which does not dissolve in the water solubility test and / or has a Davis method HLB value of 11 or less.

  First, the mixing method of each component used by this invention is demonstrated. Cement-based inorganic filler used in the present invention (consisting of cement, cement and sand, or cement and sand and gravel), polyisocyanate, polyol, foam stabilizer, catalyst and water are added in any order. Then, the mixture used in the present invention can be prepared by stirring and mixing. However, since the reaction starts immediately when the polyisocyanate comes into contact with the polyol and / or water in the presence of a catalyst, the polyisocyanate is preferably added last to form a mixture in the production process. Or you may add a catalyst finally after mixing and stirring the other components except a catalyst.

  Mixing and stirring may be performed directly in the mold, but since the mold is usually a rectangular parallelepiped, a round cup (for example, a polycup in a small-scale experiment) In large-scale production, after adding ingredients in a polymer liner circular stirring tank, etc., and stirring and mixing with a mixer (for example, a hand mixer in small-scale experiments, an electric stirring device in large-scale production) It is preferable to immediately transfer to the mold. As described above, since the urethanization reaction starts immediately with the addition of the polyisocyanate or the catalyst, it is preferable to add other components in advance and sufficiently agitate and mix to make a slurry before adding them. Since the reaction starts immediately after the start of addition and stirring of the polyisocyanate or catalyst, stirring in the circular cup is stopped for a short time (for example, several seconds) and immediately transferred to the mold. At this time, in order to obtain sufficient mixing efficiency with short stirring, stirring at high speed is preferable.

  In addition, the surface state can be visually observed and finger eroded in the state in the cup, and can be used as a measure of the progress of the curing (polymerization and crosslinking) reaction. Specifically, the time when the slurry becomes creamy (cream time), the time when the slurry becomes gelled (geltime), and the tack free time. The cream time, gel time, and tack-free time of the present invention are each usually a short time of several seconds to several tens of seconds.

  Next, after mixing in the cup for a short time (several seconds), the resulting mixture is transferred to a mold (formwork) to start the formation of the cement-based polyurethane foam composite of the present invention. The initial temperature setting of the mold may be about room temperature (about 20 ° C. to 35 ° C.). The formation of the foamed composite is accompanied by the generation of polymerization heat of polyurethane formation along with foaming, and the temperature in the mold rises. Although depending on the shape and size of the mold, the temperature in the mold usually rises to about 30 to 40 ° C. The pressure in the mold slightly increases with foaming, but it is at most about 0.5 MPa.

  After being transferred into the mold and demolded after a predetermined time, first, the appearance immediately after demolding is observed (visually). A surface having a uniform and smooth surface is regarded as acceptable (◯ mark), and a surface having a non-uniform surface and smoothness is regarded as unacceptable (× mark). Next, the cured state is observed by finger pitting. Evaluation is based on the presence or absence of stickiness and the degree of cure (crosslinking) is judged. When there is no stickiness, it is expressed as a pass (circle), and when there is a stickiness, it is expressed as a failure (× mark). On the other hand, the presence or absence of remaining nail marks is used as a measure of strength development. When there is no nail mark remaining, it is expressed as a pass (circle), and when there is a nail mark remaining, it is expressed as a failure (× mark). In the present invention, demolding after 5 minutes has been defined as a standard.

  The physical properties after demolding are measured for samples with no stickiness and no remaining nail marks (circles). The measurement items may include specific gravity, compressive strength, modulus (tensile strength), thermal conductivity, nonflammability, water permeability, soundproofing properties, etc., but physical properties according to the application of the product should be measured. In the present invention, as a basic physical property value, specific gravity and compressive strength were measured, and the obtained cementitious polyurethane foam composite was characterized.

  The cement-based polyurethane foam composite according to the present invention is characterized in that it can be demolded in a short time and can exhibit a sufficiently high hardness even immediately after demolding. That is, the demolding time is normally possible in about 5 minutes, and the compressive strength immediately after demolding gives a high value of 1 MPa or more. Therefore, the cement-based polyurethane foam composite according to the present invention can form a production time cycle in a short time, and a foam composite having good cured properties can be obtained in a process with high production efficiency. The compressive strength, for example, reaches a substantially constant value immediately after demolding after 5 minutes (for example, about 1 MPa to 1.8 MPa), and is the same compressive strength even after 1 day to 1 week. That is, good initial physical property values can be stably obtained in an extremely short time.

The foamed composite of the present invention can be used as a structural material by taking advantage of its characteristics. Specifically, relatively high compressive strength (1.0 to 1.8 MPa), lightness (specific gravity is 400 to 800 kg / m ³ ), and heat insulation or heat retention (thermal conductivity is 0.07 to 0.00). 10W / mK) is a structural material. For example, a repair material, a heat insulating material, or a heat insulating material.

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

Example 1 <Production Example of Cement / Polyurethane Foam Composite>
Portland cement 324g, polyol B (Sumiphen 1600U of Sumika Bayer Urethane Co., Ltd. product; functional group number 2, hydroxyl value 110mgKOH / g) 21.6g, water 259g, foam stabilizer in 1000ml capacity polycup 2.7 g of Toray Dow Corning Silicone SH-193 and 2.7 g of catalyst (Polycat 8 (tertiary amine) of Air Products) were added and stirred at 4,000 rpm for 4 seconds with a hand mixer. A uniform slurry was obtained. Subsequently, 194 g of isocyanate B (polymeric MDI (diphenylmethane diisocyanate); isocyanate group content of about 31.7%: Sumika Bayer Urethane Co., Ltd. product, Sumidur 44V20) was added, and the mixture was mixed at 4,000 rpm for 4 seconds with a hand mixer. After stirring, the obtained slurry was immediately filled into a mold (form) (length: 210 mm × width: 210 mm × height: 25 mm) and sealed. The mold initial temperature (initial mold temperature) was 30 ° C. After 5 minutes, the mold temperature (also referred to as “mold temperature”) had reached 40 ° C. Immediately after demolding, the cured state of the obtained foamed composite was evaluated by finger erosion. As a result, qualitative evaluation was obtained that there was no stickiness and the curing property evaluation was ◯, and the strength development evaluation was ◯ without remaining nail marks.

As a result of measuring the compressive strength of the foamed composite immediately after demolding in 5 minutes in accordance with JIS K7220, a compressive strength of 1.2 MPa was obtained. The compressive strength after 1 day after demolding was 1.4 MPa, and the compressive strength after 1 week was 1.5 MPa. In accordance with JIS A 1412-2, the thermal conductivity of the foamed composite after one week has passed, using a thermal conductivity measuring device (product name: Auto Lambda HC-074 (200) type, manufactured by Eihiro Seiki Co., Ltd.). As a result of the measurement, it was 0.08 W / mK. The density of the foamed composite after 1 week was 584 kg / m ³ .

In addition, in this Example, the reactivity was observed in the polycup as it was without transferring the same slurry mixture in the polycup to the mold (30 ° C.). The index of reactivity is as follows.
・ Cream time: Time (seconds) from mixing the slurry until the mixture starts to foam and start to rise
Gel time: Time (seconds) from mixing the slurry until the mixture starts to gel
-Tack-free time: Time (seconds) required to stop adhering to the fingertip when the rising foam surface is touched with the fingertip after slurry mixing.
As a result of observation, the cream time of the slurry was 13 seconds, the gel time was 43 seconds, and the tack free time was 48 seconds.

[Example 2]
Molding was performed in the same manner as in Example 1 except that 21.6 g of polyol B used in Example 1 was changed to 64.8 g and 194 g of isocyanate B was changed to 151 g. As a result of finger-eating evaluation of the cured state of the foamed composite immediately after demolding after 5 minutes, a qualitative evaluation was obtained that there was no stickiness and the curing property evaluation was ◯, and there was no remaining nail mark, and the strength expression evaluation was ◯. The foam composite immediately after demolding had a compressive strength of 1.4 MPa and a density of 530 kg / m ² .

[Example 3]
Molding was performed according to Example 1 except that 21.6 g of polyol B in Example 1 was changed to 108 g and 194 g of isocyanate B was changed to 108 g. As a result of finger-eating evaluation of the cured state of the foamed composite immediately after demolding after 5 minutes, a qualitative evaluation was obtained that there was no stickiness and the curing property evaluation was ◯, and there was no remaining nail mark, and the strength expression evaluation was ◯. The foam composite immediately after demolding had a compressive strength of 1.3 MPa and a density of 520 kg / m ² .

  In addition, in this Example, the reactivity was observed in the polycup as it was without transferring the same slurry mixture in the polycup to the mold (30 ° C.). The slurry had a cream time of 12 seconds, a gel time of 40 seconds, and a tack free time of 45 seconds.

Example 4 <Production Example of Mortar / Polyurethane Foam Composite>
In a 1000 ml capacity polycup, 145 g of Portland cement, 436 g of mortar sand (average particle size of about 1 mm), polyol A (manufactured by Sumika Bayer Urethane Co., Ltd., SBU polyol 0248; functional group number 3, hydroxyl value 28 mgKOH / g) 14.5 g, water 73 g, 1.2 g of foam stabilizer (silicone SH-193 of Toray Dow Corning) and 1.2 g of catalyst (Polycat 8 (tertiary amine) of Air Products) were added. The mixture was stirred with a hand mixer at 4,000 rpm for 4 seconds to obtain a uniform slurry. Next, 131 g of isocyanate A (modified polymeric MDI (polymethylene polyphenylene polyisocyanate); isocyanate group content of about 30.9%; SBU isocyanate V405; product of Sumika Bayer Urethane Co., Ltd.) was added, and 4 with a hand mixer. After stirring at 1,000 rpm for 4 seconds, the obtained slurry was immediately filled into a mold (length: 210 mm × width: 210 mm × height: 25 mm) and sealed. The mold initial temperature (mold temperature) was 30 ° C. After 5 minutes, the mold internal temperature had reached 40 ° C. Immediately after demolding, the cured state of the obtained foamed composite was evaluated by finger-corrosion. The density of the foam composite was 444 kg / m ³ .

[Example 5]
The amount of water to be blended in Example 4 was changed to 80 g, and instead of polyol A, polyol B (Sumiphen 1600U of Sumika Bayer Urethane Co., Ltd. product; functional group number about 2, hydroxyl value about 110 mgKOH / g) was used. The experiment was performed according to Example 4 except that 14.5 g was used. After 5 minutes, the temperature inside the mold had reached 40 ° C. Immediately after demolding, the cured state of the obtained foamed composite was evaluated by finger-corrosion. The density of the foam composite was 409 kg / m ³ .

[Example 6]
The amount of water to be blended in Example 4 was changed to 73 g and 87 g, and instead of polyol A, polyol B (Sumiphen 1600U of Sumika Bayer Urethane Co., Ltd. product; functional group number about 2, hydroxyl value about 110 mgKOH / g) The experiment was performed according to Example 4 except that 14.5 g was used. After 5 minutes, the mold temperature had reached 40 ° C. Immediately after demolding, the cured state of the obtained foamed composite was evaluated by finger erosion. As a result, qualitative evaluation was obtained that there was no stickiness and the curing property evaluation was ◯, and the strength development evaluation was ◯ without remaining nail marks. As a result of measuring the compressive strength of the foamed composite immediately after demolding in 5 minutes in accordance with JIS K7220, a compressive strength of 1 MPa was obtained. The compressive strength after 1 day after demolding was 1.2 MPa, and the compressive strength after 1 week after demolding was 1.2 MPa. After one week, the foamed composite had a thermal conductivity of 0.09 W / mK and a density of 618 kg / m ³ .

  In addition, in this Example, the reactivity was observed in the polycup as it was without transferring the same slurry mixture in the polycup to the mold (30 ° C.). The slurry had a cream time of 15 seconds, a gel time of 40 seconds, and a tack free time of 47 seconds.

[Example 7]
Example 1 except that 14.5 g of polyol A (SBU polyol 0248 manufactured by Sumika Bayer Urethane Co., Ltd .; functional group number about 3, hydroxyl value about 28 mg KOH / g) is used instead of polyol B in Example 6. The experiment was conducted according to 6. As a result of finger-eating evaluation of the cured state of the foamed composite obtained after demolding after 5 minutes, a qualitative evaluation was obtained that there was no stickiness and the curing property evaluation was ◯, and the strength development evaluation was ◯ without remaining nail marks. The density of the foam composite was 511 kg / m ³ .

[Example 8]
Except for using 14.5 g of a purified castor oil produced by Toyokuni Seiyaku Co., Ltd .; a polyester polyol having a functional group number of about 2.7 and a hydroxyl value of about 160 mgKOH / g) instead of polyol B in Example 6. The experiment was conducted according to Example 6. As a result of finger-eating evaluation of the cured state of the foamed composite obtained by demolding, a qualitative evaluation was obtained that there was no stickiness and the curing property evaluation was ○, and there was no remaining nail mark, and the strength expression evaluation was ○. The density of the foam composite was 468 kg / m ³ .

[Example 9]
The experiment was conducted in the same manner as in Example 6 except that 131 g of isocyanate B (polymeric MDI (SBU isocyanate 44V20); isocyanate group content: about 31.7%) was used instead of isocyanate A in Example 6. As a result of finger-eating evaluation of the cured state of the foamed composite obtained after demolding after 5 minutes, a qualitative evaluation was obtained that there was no stickiness and the curing property evaluation was ◯, and the strength development evaluation was ◯ without remaining nail marks. The compressive strength immediately after demolding was 1.2 MPa, the compressive strength after 1 day after demolding was 1.0 MPa, and the compressive strength after 1 week after demolding was 1.2 MPa. The density of the foam composite was 600 kg / m ³ .

  In addition, in this Example, the reactivity was observed in the polycup as it was without transferring the same slurry mixture in the polycup to the mold (30 ° C.). The slurry had a cream time of 12 seconds, a gel time of 40 seconds, and a tack free time of 46 seconds.

[Example 10]
In a polycup with a capacity of 1000 ml, 145 g of Portland cement, 291 g of sand (average particle size 1 mm), polyol B (Sumiphen 1600U of Sumika Bayer Urethane Co., Ltd. product; functional group number 2, hydroxyl value of about 110 mg KOH / g) 29 g, 87 g of water, 1.2 g of foam stabilizer (silicone SH-193 of Toray Dow Corning) and 1.2 g of catalyst (Polycat 8 (tertiary amine) of Air Products) are added with a hand mixer. The mixture was stirred at 4,000 rpm for 4 seconds to obtain a uniform slurry. Next, 262 g of isocyanate A (modified diphenylmethane diisocyanate (MDI); isocyanate group content of about 30.9%) was added and stirred for 4 seconds at 4,000 rpm with a hand mixer, and the resulting slurry was immediately molded (longitudinal). : 210 mm × width: 210 mm × height: 25 mm) and sealed. After 5 minutes, the mold internal temperature (mold temperature) had reached 40 ° C. Immediately after demolding, the cured state of the obtained foamed composite was evaluated by finger erosion. As a result, qualitative evaluation was obtained that there was no stickiness and the curing property evaluation was ◯, and the strength development evaluation was ◯ without remaining nail marks. The compression strength of the foamed composite immediately after demolding in 5 minutes was 1.6 MPa, the compression strength after 1 day was 1.6 MPa, and the compression strength after 1 week was 1.7 MPa. The thermal conductivity of the foam composite after 1 week was 0.08 W / mK. The density of the foam composite was 600 kg / m ³ .

  In addition, in this Example, the reactivity was observed in the polycup as it was without transferring the same slurry mixture in the polycup to the mold (30 ° C.). The slurry had a cream time of 12 seconds, a gel time of 51 seconds, and a tack free time of 60 seconds.

  The above experimental results are summarized in Tables 2-1 and 2-2.

<Polyol water solubility test>
Polyol A used in Examples 1 to 7 by mixing and stirring the polyol and water in a test tube under the condition of water / polyol = 6/1 weight ratio and visually checking the state after standing for 1 day. The water solubility of ~ C was tested. In the visual evaluation, the case of “white turbidity or layer separation” after standing for 1 day was evaluated as “not dissolved”. On the other hand, a case where the state after standing for 1 day was “clear or slightly cloudy” was evaluated as “dissolve”. The obtained results are shown in Table 3.

<Polyol HLB (Davis Method)>
The Davis method HLB value of the polyol used in the examples was determined by the method described in the above-mentioned document (Journal of Colloid and Interface Science 298 (2006) 441-450) by Xiaowen Guo et al. For example, the HLB value of polyol B (polyol B is a bifunctional polyol having propylene glycol as a starting material and ring-opening addition of propylene oxide and having a molecular weight of 1020 and having two hydroxyl groups at the end) is calculated as follows: it can:
HLB = 7 + (− 0.475 × 3) + 1.3 × 2 + 16.3 molx (−0.15) + 1.9 × 2 = 9.5. The obtained results are also shown in Table 3.

From the above results, it is obtained when the polyol used in the present invention is a polyether polyol having a hydroxyl value in the range of 5 to 300 (mg KOH / g) and a functional group number in the range of 2 to 6. It can be seen that the cement-based polyurethane foam composite exhibits a high compressive strength of 1 MPa or more with a short demolding time of 5 minutes. It can also be seen that the density of the foamed composite is in the range of 400 to 800 Kg / m ³ and a sufficient weight reduction is achieved. Moreover, the water solubility test results of the polyols A to C were all cloudy or separated into layers, and it was determined that these polyols were not dissolved in water (Table 3). Furthermore, it was also confirmed that the Davis method HLB values of the polyols A to C are within the predetermined range of the present invention (HLB is 11 or less).

[Comparative Example 1]
Except for changing polyol B in Example 6 to 14.5 g of polyol D (Sumiphen TS, manufactured by Sumika Bayer Urethane Co., Ltd .; polyether polyol having a functional group number of about 5.6 and a hydroxyl value of about 380 mgKOH / g). The experiment was conducted according to Example 6. As a result of evaluating the cured state of the foamed composite obtained by demolding, qualitative evaluation was obtained that there was stickiness and the curing property evaluation was x, and there was a nail mark remaining and the strength expression evaluation was x. As a result of measuring the compressive strength of the foamed composite immediately after demolding in 5 minutes in accordance with JIS K7220, a compressive strength of 0.6 MPa was obtained. The compressive strength after 1 day after demolding was 0.6 MPa, and the compressive strength after 1 week after demolding was 0.6 MPa. The density of the foam composite was 605 kg / m ³ .

[Comparative Example 2]
Except for changing polyol B in Example 6 to 14.5 g of polyol E (SBU polyol 0497 manufactured by Sumika Bayer Urethane Co., Ltd .; polyether polyol having a functional group number of about 2 and a hydroxyl value of about 500 mg KOH / g). The experiment was conducted according to Example 6. As a result of evaluating the cured state of the foamed composite obtained by demolding, qualitative evaluation was obtained that there was stickiness and the curing property evaluation was x, and there was a nail mark remaining and the strength expression evaluation was x. The density of the foam composite was 620 kg / m ³ .

[Comparative Example 3]
Except for changing polyol B in Example 6 to 14.5 g of polyol F (SBU polyol 0480 manufactured by Sumika Bayer Urethane Co., Ltd .; polyether polyol having 3 functional groups and a hydroxyl value of about 550 mg KOH / g). The experiment was conducted according to Example 6. As a result of evaluating the cured state of the foamed composite obtained by demolding, qualitative evaluation was obtained that there was stickiness and the curing property evaluation was x, and there was a nail mark remaining and the strength expression evaluation was x. The density of the foam composite was 579 kg / m ³ .

[Comparative Example 4]
Except that polyol B in Example 6 is 14.5 g of polyol G (Sumiphen VB manufactured by Sumika Bayer Urethane Co., Ltd .; polyether polyol having a functional group number of 4 and a hydroxyl value of about 630 mg KOH / g). The experiment was conducted according to 6. As a result of evaluating the cured state of the foamed composite obtained by demolding, qualitative evaluation was obtained that there was stickiness and the curing property evaluation was x, and there was a nail mark remaining and the strength expression evaluation was x. As a result of measuring the compressive strength of the foamed composite immediately after demolding in 5 minutes in accordance with JIS K7220, a compressive strength of 0.6 MPa was obtained. The compressive strength after 1 day after demolding was 0.6 MPa, and the compressive strength after 1 week after demolding was 0.6 MPa. The density of the foam composite was 422 kg / m ³ .

  In this comparative example, the reactivity was observed in the polycup as it was without transferring the same slurry mixture in the polycup to the mold (30 ° C.). The slurry had a cream time of 9 seconds, a gel time of 30 seconds, and a tack free time of 36 seconds.

[Comparative Example 5]
An experiment was performed according to Example 6 except that the polyol B in Example 6 was changed to 0 g and the isocyanate A was changed to 145 g. As a result of evaluating the cured state of the foamed composite obtained by demolding, qualitative evaluation was obtained that there was stickiness and the curing property evaluation was x, and there was a nail mark remaining and the strength expression evaluation was x. As a result of measuring the compressive strength of the foamed composite obtained immediately after demolding in 5 minutes in accordance with JIS K7220, a compressive strength of 0.7 MPa was obtained. The compressive strength after 1 day after demolding was 0.7 MPa, and the compressive strength after 1 week after demolding was 0.7 MPa. The density of the foam composite was 605 kg / m ³ .

  In this example, the reactivity was observed in the polycup as it was without transferring the same slurry mixture in the polycup to the mold separately (30 ° C.) The cream time of the slurry was 18 seconds, and the gel time was 45 seconds and tack free time was 50 seconds.

  The results of the above comparative examples are summarized in Table 4.

<Polyol water solubility test (comparative example)>
About each polyol DG used by the comparative example, a polyol and water were mixed and stirred in a test tube on the conditions of water / polyol = 6/1 weight ratio, and the state after standing for one day was confirmed visually. The water solubility of polyols D to G used in Comparative Examples 1 to 5 was tested. In the visual evaluation, the case of “white turbidity or layer separation” after standing for 1 day was evaluated as “not dissolved”. On the other hand, a case where the state after standing for 1 day was “clear or slightly cloudy” was evaluated as “dissolve”. The results obtained are shown in Table 5.

<Polyol HLB (Davis Method)>
The Davis method HLB value of the polyol used in the comparative example was determined by the method described in the above-mentioned document by Xiaowen Guo et al. (Journal of Colloid and Interface Science 298 (2006) 441-450). The obtained results are shown together in Table 5.

  It is clear from the above comparative examples that even if the number of functional groups of the polyol raw material is in the range of 2 to 6 of the present invention requirement, the hydroxyl value is out of the range of 5 to 300 mgKOH / g, and / or If the water solubility is high (or the Davis HLB value is higher than the predetermined value), the curing property (degree of crosslinking) and the strength at the time of demolding for 5 minutes become insufficient, and the predetermined performance of the present invention cannot be obtained. .

The cement-based polyurethane foam composite according to the present invention makes it possible to obtain a composite material having a desired low density and strength in a short demolding time, and thus in a short time cycle that is industrially advantageous, Development as a new structural material that makes use of characteristics such as high compressive strength (1.0 to 1.8 MPa) and lightness (specific gravity of 400 to 800 kg / m ³ ) has become possible.

Claims (10)

Cement-based polyurethane obtained by foaming a mixture containing cement, cement-sand, or cement-based inorganic filler consisting of cement, sand and gravel, polyisocyanate, polyol, foam stabilizer, catalyst and water In foam composites,
A cement-based polyurethane foam composite, wherein the polyol contains a polyether polyol having a hydroxyl value of 5 to 300 mgKOH / g and a functional group number of 2 to 6.   The foamed composite according to claim 1, wherein the polyol is a polyether polyol that does not dissolve in the water solubility test and / or has a Davis HLB value of 11 or less. The ratio of the cementitious inorganic filler and the polyurethane resin of the foam composite is 50:50 to 90:10, and the foam composite density is 400 to 800 Kg / m ³ . Foam composite.   The foamed composite according to any one of claims 1 to 3, wherein the time until the mixture is poured into a mold and removed is within 5 minutes at a mold temperature of 30 to 40 ° C.   The foamed composite according to any one of claims 1 to 4, wherein the polyisocyanate is polymethylene polyphenylene polyisocyanate or a modified product thereof.   Cement, cement and sand, or cement-based inorganic filler consisting of cement, sand and gravel, polyisocyanate, polyol, foam stabilizer, catalyst and a mixture containing water are mixed and stirred to foam, A method for producing a cement-based polyurethane foam composite, wherein the polyol contains a polyether polyol having a hydroxyl value of 5 to 300 mg KOH / g and a functional group number of 2 to 6 .     The method for producing a foam composite according to claim 6, wherein the polyol is a polyether polyol that does not dissolve in a water solubility test and / or has a Davis method HLB value of 11 or less.   A structural material comprising the foam composite according to claim 1. High strength at the time of demolding (compressive strength is 1.0 to 1.8 MPa), lightness (specific gravity is 400 to 800 kg / m ³ ), and heat insulation or heat retention (thermal conductivity is 0.07 to 0.10 W /) The structural material of claim 8 having mK).   The structural material according to claim 8 or 9, wherein the structural material is used as a heat insulating material or a heat insulating material.