complex

Abstract

To provide a resin foam that retains high thermal insulation performance of phenolic resin foam while exhibiting superior compression and waterproof properties.SOLUTION: A complex of a phenolic resin foam and a polyurea layer or a polyurea urethane layer is provided. The phenolic resin foam has its surface at least partly coated with the polyurea layer or the polyurea urethane layer. The polyurea layer or the polyurea urethane layer has a thickness of 0.2 mm or more and 5.0 mm or less. The polyurea layer is free from a urethane bond. The ratio of urethane bonds to the total number of urea bonds and urethane bonds in the polyurea urethane layer is more than 0% to 30% or less.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a composite of a phenolic resin foam and a polyurea layer or a polyurea urethane layer. [Background technology]

[0002] Phenolic resin foam is widely used as a building material and general industrial material because it has high thermal insulation, flame retardancy, and heat resistance among foamed plastic insulation materials. In recent years, phenolic resin foam has also come to be widely used from the perspective of energy conservation. However, there has been a demand for a resin foam that not only utilizes the advantages of phenolic resin foam, such as its superior thermal conductivity, but also possesses excellent compressive strength and waterproofing properties.

[0003] For the purpose of improving compressive strength, for example, Patent Document 1 describes an attempt to provide a reinforcing waterproof layer on the surface of a thermal insulation foam layer.

[0004] However, the technology described in Patent Document 1 does not specifically disclose the types of thermal insulation foam layer and reinforcing waterproof layer, nor the structure of their composite, and therefore it was not possible to obtain a resin foam that exhibits sufficient compressive strength. [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] Japanese Patent Publication No. 2009-264093 [Overview of the project] [Problems that the invention aims to solve]

[0006] The present invention aims to provide a resin foam that has high thermal insulation performance while also possessing excellent compression and waterproofing properties. [Means for solving the problem]

[0007] In other words, the present invention is as follows. [1] A composite of a phenolic resin foam and a polyurea layer or a polyurea urethane layer, At least a portion of the surface of the phenolic resin foam is covered with the polyurea layer or polyurea urethane layer. The thickness of the polyurea layer or polyurea urethane layer is 0.2 mm or more and 5.0 mm or less. The aforementioned polyurea layer does not have urethane bonds, A composite in which the ratio of the number of urethane bonds to the total number of urea bonds and urethane bonds in the polyurea-urethane layer is greater than 0% and less than or equal to 30%. [2] The phenolic resin foam is a plate-shaped rectangular parallelepiped, The composite according to [1], wherein the surfaces of two opposing sides of the phenolic resin foam in the thickness direction are covered with the polyurea layer or polyurea urethane layer. [3] The phenolic resin foam is a plate-shaped rectangular parallelepiped, The composite according to [1], wherein the surfaces of four sides of the phenolic resin foam, excluding one pair of opposing surfaces in the thickness direction, are covered with the polyurea layer or polyurea urethane layer. [4] The composite according to [1], wherein all surfaces of the phenolic resin foam are covered with the polyurea layer or the polyurea urethane layer. [5] The compressive strength of the composite is 19 N / cm 2 More than 55N / cm 2 The composites described in [1] to [4], wherein the compressive strength / density value is 0.6 or less. [6] The moisture permeability of the composite at 25°C and 90%RH is 9 g / (m²). 2 The complexes described in [1] to [4], which are less than or equal to 24 hours. [7] The compressive strength of the composite is 19 N / cm 2 More than 55N / cm 2 The following conditions must be met: the compressive strength / density ratio must be 0.6 or less, and the moisture permeability at 25°C and 90% RH must be 9 g / (m²). 2 The complexes described in [1] to [4], which are less than or equal to 24 hours.

Advantages of the Invention

[0008] According to the present invention, it is possible to provide a composite having excellent compression characteristics and waterproof characteristics while having high heat insulation performance of a phenolic resin foam.

Brief Description of the Drawings

[0009] [Figure 1] FIG. 1 is a cross-sectional view schematically showing an example of the composite of the present embodiment. [Figure 2] FIG. 2 is a perspective view schematically showing another example of the composite of the present embodiment.

Mode for Carrying Out the Invention

[0010] In the present invention, the periphery of the phenolic resin foam is coated with a polyurethane layer or a polyurethane urethane layer having impact resistance, so that while having high heat insulation performance, it has excellent compression characteristics and waterproof characteristics that have not been realized so far. A composite has been found.

[0011] For the composite of the present embodiment, the compression strength, moisture permeability, density, and thermal conductivity are determined by the methods described in the examples. The density, thermal conductivity, and closed-cell ratio of the phenolic resin foam are determined by the methods described in the examples. Unless otherwise specified, the density of the composite and the phenolic resin foam refers to the apparent overall density measured in accordance with JIS K7222. Unless otherwise specified, the thermal conductivity refers to the thermal conductivity at 23°C. Unless otherwise specified, the moisture permeability refers to the moisture permeability at 25°C and 90% RH.

[0012] In this embodiment, the "thickness" direction refers to the direction of the shortest side among the three sides of the length, width, and height of the laminate. In this embodiment, terms such as "first" and "second" may be used, but these are only intended to distinguish one element from another and do not limit the position, size, or quantity of an element. Since the attached drawings are schematic diagrams prioritizing ease of understanding of the present invention, the scale of each element in the drawings is not accurate.

[0013] Hereinafter, a mode for carrying out the present invention (hereinafter referred to as "this embodiment") will be described in detail.

[0014] · Composite The composite of this embodiment is a composite of a phenolic resin foam and a polyurea layer or a polyureaurethane layer, and at least a part of the surface of the phenolic resin foam is covered with a polyurea layer or a polyureaurethane layer.

[0015] · Phenolic resin foam The phenolic resin foam constituting the composite of this embodiment is a structure obtained by foaming and curing a phenolic resin composition. The "phenolic resin foam" in the composite of this embodiment is a concept including the phenolic resin foam itself and the case where a facing material or siding is provided on at least a part of the surface of the phenolic resin foam.

[0016] The density of the phenolic resin foam is not particularly limited, but typically it is 20 kg / m 3 or more and 80 kg / m 3 or less, preferably 35 kg / m 3 or more and 70 kg / m 3 or less, and more preferably 45 kg / m 3 or more and 65 kg / m 3 or less. When the density of the phenolic resin foam is 20 kg / m 3 or more, mechanical strengths such as compressive strength and flexural strength can be ensured, and breakage during handling of the plate-like phenolic resin foam can be reduced. On the other hand, when the density of the phenolic resin foam is 80 kg / m 3The following conditions prevent an increase in heat transfer in the phenolic resin portion of the phenolic resin foam board, thus maintaining its thermal insulation performance. The density of the phenolic resin foam can be adjusted to a desired value mainly by changing the proportion of the foaming agent, the temperature of the foamed phenolic resin composition, the timing of pre-molding in the process of extruding the mixed foamed phenolic resin composition onto the bottom material, the ratio of the amount of foaming agent added to the amount of organic acid used as an acidic curing agent added, and curing conditions such as temperature and residence time.

[0017] The thickness of the phenolic resin foam is not particularly limited and can be set as appropriate. The thickness of the phenolic resin foam is preferably 30 mm to 200 mm. The thickness is preferably 30 mm to 200 mm, more preferably 35 mm to 200 mm, and even more preferably 40 mm to 200 mm.

[0018] The closed-cell ratio of the phenolic resin foam is not particularly limited, but is typically 85% or higher, preferably 90% or higher. Alternatively, the closed-cell ratio may be, for example, 99% or less, 98% or less, or 97% or less. Since the closed-cell ratio serves as an indicator of thermal insulation performance, a ratio of 85% or higher is preferable as it indicates good thermal insulation performance.

[0019] The closed-cell ratio can be adjusted to the desired value mainly by controlling the reactivity and temperature of the phenolic resin, as well as by changing the curing temperature conditions.

[0020] The thermal conductivity of the phenolic resin foam is not particularly limited, but is typically 0.026 W / (m·K) or less, preferably 0.016 W / (m·K) or more and 0.025 W / (m·K) or less, more preferably 0.016 W / (m·K) or more and 0.024 W / (m·K) or less, and even more preferably 0.016 W / (m·K) or more and 0.023 W / (m·K).

[0021] The shape of the phenolic resin foam is not particularly limited and can be any shape. Examples of shapes of the phenolic resin foam include rectangular parallelepipeds (e.g., plate-like, layered, sheet-like, etc.), polyhedra other than rectangular parallelepipeds (e.g., regular polyhedra such as tetrahedrons, octahedrons, dodecahedrons, and icosahedrons), spheres, pyramidal pyramids, cones, tori, hollow cylinders, solid cylinders (cylinders), and irregular shapes. In one embodiment, the phenolic resin foam is a rectangular parallelepiped. In another embodiment, the phenolic resin foam is a plate-like rectangular parallelepiped.

[0022] The phenolic resin foam may be a single molded product or a combination of scraps from multiple phenolic foams.

[0023] If the phenolic resin foam has a facing material or siding on at least a portion of its surface, the polyurea layer or polyurea-urethane layer may cover the surface of the facing material or siding (i.e., the side of the facing material or siding opposite to the phenolic resin foam side), or it may cover the portion of the phenolic resin foam that does not have the facing material or siding, or a combination thereof, i.e., the polyurea layer or polyurea-urethane layer may cover both the portion of the phenolic resin foam that does not have the facing material or siding and the surface of the facing material or siding.

[0024] • Polyurea layer or polyurea urethane layer The polyurea layer or polyurea-urethane layer in this embodiment covers at least a portion of the surface of the phenolic resin foam. The polyurea layer or polyurea-urethane layer imparts compression properties and waterproofing properties to the composite.

[0025] In this specification, a layer in which only urea bonds are present and urethane bonds are absent is referred to as a "polyurea layer."

[0026] In the composite of this embodiment, the polyurea-urethane layer has urea bonds and urethane bonds, and the ratio of the number of urethane bonds to the total number of urea bonds and urethane bonds is greater than 0% and 30% or less. When the ratio of urethane bonds is 30% or less, the compressive strength of the composite is improved. The ratio of the number of urea bonds to the number of urethane bonds can be adjusted by the ratio of the number of hydroxyl groups to the total number of amino groups and hydroxyl groups in the second agent described later.

[0027] The proportion of urethane bonds in the polyurea urethane layer is greater than 0% and 30% or less, preferably 5-25%, and more preferably 10-20%.

[0028] The proportion of urethane bonds in the polyurea layer or polyurea-urethane layer is determined after the polyurea layer or polyurea-urethane layer is peeled from the phenolic resin foam and solidified. 13 It can be measured by known methods such as 13C nuclear magnetic resonance (NMR).

[0029] The thickness of the polyurea layer or polyurea urethane layer is 0.2 mm or more and 5.0 mm or less. If the thickness of the polyurea layer or polyurea urethane layer is less than 0.2 mm, sufficient compressive strength cannot be obtained, and it becomes difficult to form a coating film. If the thickness of the polyurea layer or polyurea urethane layer exceeds 5.0 mm, the thermal conductivity deteriorates and it becomes cost-ineffective. In one embodiment, the thickness of the polyurea layer or polyurea urethane layer is 0.2 mm or more, 0.5 mm or more, 1.0 mm or more, 1.5 mm or more, 2.0 mm or more, 2.5 mm or more, 3.0 mm or more, 3.5 mm or more, 4.0 mm or more, or 4.5 mm or more. In another embodiment, the thickness of the polyurea layer or polyurea urethane layer is 5.0 mm or less, 4.5 mm or less, 4.0 mm or less, 3.5 mm or less, 3.0 mm or less, 2.5 mm or less, 2.0 mm or less, 1.5 mm or less, 1.0 mm or less, or 0.5 mm or less. In yet another embodiment, the thickness of the polyurea layer or polyurea urethane layer is 0.5 mm or more and 3.0 mm or less.

[0030] The thickness of the polyurea layer or polyurea-urethane layer can be determined by cutting perpendicularly to the surface of the composite coated with the polyurea layer or polyurea-urethane layer, then peeling off only the polyurea layer or polyurea-urethane layer from the cut surface, and measuring it using calipers.

[0031] The polyurea layer or polyurea-urethane layer only needs to cover at least a portion of the surface of the phenolic resin foam. Covering the surface or portion of the phenolic resin foam exposed to the external environment with the polyurea layer or polyurea-urethane layer enhances its waterproofing properties. The polyurea layer or polyurea-urethane layer may cover the entire surface of the phenolic resin foam. Furthermore, if the phenolic resin foam is a plate-shaped rectangular parallelepiped, the layer may cover any one, two (two opposing or two non-opposing), three, or four of the four side surfaces of the phenolic resin foam in the thickness direction. Furthermore, if the phenolic resin foam is a plate-shaped rectangular parallelepiped, the layer may cover one or two of the two opposing surfaces in the thickness direction of the phenolic resin foam. Furthermore, if the phenolic resin foam is a plate-shaped rectangular parallelepiped, the layer may cover one or two of the two opposing surfaces in the thickness direction, and also cover any one, two (two opposing or two non-opposing), three, or four of the four side surfaces in the thickness direction.

[0032] Furthermore, by covering one or more sides of the phenolic resin foam with a polyurea layer or polyurea-urethane layer in the thickness direction, the compressive strength of the composite in the thickness direction is also improved.

[0033] The polyurea layer or polyurea-urethane layer covering the same or different surfaces of the phenolic resin foam may have the same or different thicknesses and compositions.

[0034] Figure 1 is a schematic cross-sectional view showing an example of the composite of this embodiment. In the composite 1 of Figure 1, the phenolic resin foam 10 is a plate-shaped rectangular parallelepiped, and the surfaces of two opposing sides of the phenolic resin foam 10 in the thickness direction are covered with a polyurea layer or a polyurea urethane layer 20. In this example of Figure 1, the phenolic resin foam 10 has a surface material 11 on a pair of opposing surfaces in the thickness direction.

[0035] Figure 2 is a schematic perspective view showing another example of the composite of this embodiment. In this composite 1 of Figure 2, the phenolic resin foam is a plate-shaped rectangular parallelepiped, and the surfaces of all four sides (i.e., all sides) except for a pair of opposing faces in the thickness direction of the phenolic resin foam are covered with a polyurea layer or a polyurea urethane layer 20. In this example of Figure 2, the phenolic resin foam has a face material 11 on a pair of opposing faces in the thickness direction.

[0036] The thermal conductivity of the composite in the thickness direction at 23°C is preferably 0.026 W / (m·K) or less, more preferably 0.016 W / (m·K) or more and 0.025 W / (m·K) or less, even more preferably 0.016 W / (m·K) or more and 0.024 W / (m·K) or less, and particularly preferably 0.016 W / (m·K) or more and 0.023 W / (m·K). The thermal conductivity mainly depends on the performance of the phenolic resin foam and can be adjusted, for example, by the composition and viscosity of the phenolic resin during the production of the phenolic resin foam, the type and proportion of the foaming agent, the proportion of the bubble nucleating agent, the curing conditions, the foaming conditions, and furthermore, the thickness of the polyurea layer or polyurea urethane layer.

[0037] The compressive strength of the composite is 19 N / cm². 2 More than 55N / cm 2 The following is preferable, and more preferably, 25 N / cm² 2 More than 55N / cm 2 The following applies: The compressive strength of the composite can be adjusted, for example, by the composition and viscosity of the phenolic resin during the production of the phenolic resin foam, the type and proportion of the blowing agent, the proportion of the bubble nucleating agent, the curing conditions, the foaming conditions, and the thickness of the polyurea layer or polyurea urethane layer.

[0038] The density of the composite is 30-200 kg / m³. 3 Preferably, it is 40 to 150 (kg / m 3 The density of the composite can be adjusted, for example, by the composition and viscosity of the phenolic resin during the production of the phenolic resin foam, the type and proportion of the blowing agent, the proportion of the bubble nucleating agent, the curing conditions, the foaming conditions, and the thickness of the polyurea layer or polyurea urethane layer.

[0039] Compressive strength of composite (N / cm 2 ) density (kg / m³ 3 The value obtained by dividing the compressive strength by the density is preferably 0.60 or less, more preferably 0.50 or less, and even more preferably 0.45 or less. If the value obtained by dividing the compressive strength by the density is 0.60 or less, it is possible to obtain a composite with excellent compressive strength.

[0040] The waterproof properties of the composite material can be evaluated by its moisture permeability. The moisture permeability of the composite material is 9 g / (m³). 2 It is preferable that it is 24 hours or less, and more preferably 8 g / (m 2 • 24h) or less, and more preferably 7g / (m³ 2 • 24h) or less. Moisture permeability is 9g / (m 2 If the water absorption of the composite is less than 24 hours, the absorption of water in the composite can be suppressed, and dimensional changes in the composite can be minimized. Waterproofing properties can be enhanced by coating with a polyurea layer or a polyurea-urethane layer.

[0041] The method for producing phenolic resin foam is not particularly limited and can be produced by known methods. Phenolic resin foam can be obtained, for example, by foaming and curing a foamable phenolic resin composition containing a phenolic resin, a surfactant, a foaming agent, and an acidic curing agent. Phenolic resin foam can also be obtained by methods described, for example, in Japanese Patent Application Publication No. 2020-139088 and International Publication No. 2019 / 208811. Furthermore, Neoma® foam manufactured by Asahi Kasei Building Materials Co., Ltd. can be suitably used as the phenolic resin foam.

[0042] The phenolic resin foam may have a facing material on any of its surfaces. A flexible facing material is used as the facing material. Examples of flexible facing materials include those described in Japanese Patent Publication No. 2020-139088 and International Publication No. 2019 / 208811.

[0043] One method for forming a polyurea layer or polyurea urethane layer is to use, for example, a first agent containing a polyisocyanate prepolymer and a second agent containing a polyamine and a polyol.

[0044] • First agent Examples of commercially available polyisocyanate prepolymers included in the first component include product name: Rimquick 15 Main Component (manufactured by Tama Waterproofing Technology Co., Ltd.).

[0045] • Second drug Examples of commercially available second-component products include product name: Rimquick 15 Hardener (manufactured by Tama Waterproofing Technology Co., Ltd.).

[0046] The mixing ratio of the first and second agents is, for example, 1:1 by volume.

[0047] For example, the first and second components are separately heated to approximately 60°C to reduce their viscosity to 100 mP·s, then pumped through a hose heated to the same temperature to a spray gun at 10 MPa, where they are mixed at the tip of the gun and spray-coated.

[0048] The polyurea layer or polyurea-urethane layer is obtained, for example, by reacting the first and second components by heating and stirring. The first component contains a polyisocyanate prepolymer obtained by reacting a polyisocyanate having two or more isocyanate groups with a polyol having two or more hydroxyl groups. The second component contains a polyamine having two or more amino(-NH2) groups and optionally a polyol having two or more hydroxyl groups, where the ratio of hydroxyl groups to the total number of amino groups in the polyamine and hydroxyl groups in the polyol is 0-30%. The ratio of urethane bonds in the resulting polyurea layer or polyurea-urethane layer can be adjusted by the ratio of hydroxyl groups to the total amount of amino groups and hydroxyl groups in the second component.

[0049] The polyisocyanate forming the polyisocyanate prepolymer has two or more isocyanate groups. The number of isocyanate groups is, for example, 2 to 5, and preferably 2 to 3.

[0050] Examples of polyisocyanates include aromatic isocyanates and aliphatic isocyanates.

[0051] Aromatic isocyanates include diphenylmethane diisocyanate (MDI) and toluene diisocyanate (TDI).

[0052] Aliphatic isocyanates include hexamethylene diisocyanate (HDI) and isophorone diisocyanate (IPDI).

[0053] The polyol forming the polyisocyanate prepolymer has two or more hydroxyl groups. The number of hydroxyl groups is, for example, 2 to 5, and preferably 2 to 3.

[0054] Examples of polyols having two or more hydroxyl groups include polyether polyols such as polypropylene glycol, polyester polyols, acrylic polyols, and polymer polyols. Examples of commercially available polyols having two or more hydroxyl groups include the NOF Corporation's trade names Uniol D-1000, D-1500, D-2000, D-3000, D-4000, T-1500, T-3000, T-4000, and T-5000.

[0055] Polyisocyanate prepolymers are obtained by reacting some of the isocyanate groups of polyisocyanate with a polyol.

[0056] The proportion of isocyanate groups with a molecular weight of 42 in the polyisocyanate prepolymer (NCO concentration) is, for example, 8% by weight or more and 16% by weight or less.

[0057] Furthermore, the first component may also contain a plasticizer in an amount of approximately 0-10% relative to the total amount of polyisocyanate prepolymer and plasticizer.

[0058] The plasticizer is not particularly limited, and any known plasticizer can be used. Examples of plasticizers include phthalate ester plasticizers and ether plasticizers.

[0059] Examples of phthalate ester plasticizers include diisodecyl phthalate, bis(2-ethylhexyl) phthalate, diisononyl phthalate, diundecyl phthalate, dimethyl phthalate, diethyl phthalate, and dibutyl phthalate. The plasticizer described in Japanese Patent Publication No. 2020-133168 is also an example.

[0060] Furthermore, flame-retardant plasticizers such as halogenated phosphate esters, halogenated condensed phosphate esters, non-halogenated phosphate esters, and non-halogenated condensed phosphate esters can be used. By using flame-retardant plasticizers, the oxygen index of the polyurea layer or polyurea-urethane layer can be increased to impart self-extinguishing properties.

[0061] The number of amino groups in the polyamine having two or more amino groups in the second agent is, for example, 2 to 5, preferably 2 to 3.

[0062] Examples of polyamines include aromatic diamines and aliphatic diamines.

[0063] Examples of aromatic diamines include 2,4-diethyl-6-methyl-1,3-benzenediamine, 2,6-diethyl-4-methyl-1,3-benzenediamine, 4,6-diethyl-2-methyl-1,3-benzenediamine, and 2,5-diethyl-4-methyl-1,3-benzenediamine.

[0064] Examples of aliphatic diamines include polyoxypropylenediamine, polyoxytrimethylenediamine (also known as polytrimethylene etherdiamine), and polyoxytetramethylenediamine (also known as polytetramethylene etherdiamine).

[0065] Polyamines may be used individually or in combination of two or more types.

[0066] The second component, a polyol, has two or more hydroxyl groups. The number of hydroxyl groups in the polyol is, for example, 2 to 5, preferably 2 to 3.

[0067] Examples of polyols having two or more hydroxyl groups include the polyols exemplified in the first agent. The polyol of the second agent may be the same as or different from the polyol of the first agent.

[0068] The second component, the polyol, may be used alone or in combination of two or more types.

[0069] Furthermore, the second component may also contain a plasticizer in an amount of approximately 0-10% relative to the total amount of polyamine, polyol, and plasticizer.

[0070] The plasticizer is not particularly limited, and any known plasticizer can be used. Examples of plasticizers include those exemplified in the first component. The plasticizers in the first and second components may be the same or different.

[0071] The second agent may further contain an antioxidant, a reaction catalyst, an antifoaming agent, and a pigment.

[0072] The ratio of the number of amino groups in the polyamine of the second agent to the number of hydroxyl groups in the polyol and the total number of hydroxyl groups is 0-30%. If the proportion of hydroxyl groups exceeds 30%, the proportion of urea bonds in the polyurea urethane layer decreases, and sufficient strength of the polyurea urethane layer cannot be obtained. On the other hand, if the proportion of hydroxyl groups is 30% or less, a certain amount of urea bonds are present in the polyurea urethane layer, thus improving performance in terms of strength. In one embodiment, the ratio of the number of amino groups in the polyamine of the second agent to the number of hydroxyl groups in the polyol and the total number of hydroxyl groups is 5% or more, 10% or more, 15% or more, 20% or more, or 25% or more. In another embodiment, the ratio of the number of amino groups in the polyamine of the second agent to the number of hydroxyl groups in the polyol and the total number of hydroxyl groups is 30% or less, 25% or less, 20% or less, 15% or less, 10% or less, or 5% or less. [Examples]

[0073] The present invention will be described in more detail below with reference to examples and comparative examples, but the present invention is not limited thereto.

[0074] The moisture content and viscosity of the phenolic resin synthesized in the examples were measured as follows.

[0075] <Moisture content of phenolic resin> Phenolic resin was dissolved in dehydrated methanol (manufactured by Kanto Chemical Co., Ltd.), with a moisture content measured, in a concentration ranging from 3% to 7% by mass to prepare a solution. The moisture content of the phenolic resin was determined by subtracting the moisture content of the dehydrated methanol from the moisture content of the solution. A Karl Fischer moisture meter (Kyoto Electronics Manufacturing Co., Ltd., MKC-510) was used for the measurement.

[0076] <Viscosity of phenolic resin> The viscosity of the phenolic resin was measured using a rotational viscometer (Toki Sangyo Co., Ltd., R-100 model, rotor section 3°×R-14) after stabilization at 40°C for 3 minutes.

[0077] <Synthesis of phenolic resin> 3500 kg of 52% by mass formaldehyde and 2510 kg of 99% by mass phenol were charged into the reactor and stirred with a propeller-type stirrer. The internal liquid temperature of the reactor was adjusted to 40°C using a temperature controller. Then, the temperature was raised while adding a 50% by mass sodium hydroxide aqueous solution to carry out the reaction. The Ostwald viscosity was 6.0 × 10⁻⁶. -5 m 2 When the reaction reached a viscosity of / s (measured at 25°C), the reaction mixture was cooled, and 570 kg of urea (equivalent to 15 mol% of the formaldehyde charge) was added. The reaction mixture was then cooled to 30°C, and the pH was neutralized to 6.3 with a 50 wt% aqueous solution of p-toluenesulfonic acid monohydrate. The neutralized reaction mixture was dehydrated at 60°C, and its viscosity and water content were measured. The viscosity was 6,100 mPa·s, and the water content was 5.1 mass%.

[0078] (Example 1) <Manufacturing of phenolic resin foam> In the production of phenol foam according to Example 1 of Japanese Patent Publication No. 2021-192962, a phenol resin foam with a thickness of 45 mm was obtained in the same manner, except that 0.3% by mass of nitrogen relative to the foaming agent was used as a foaming nucleating agent instead of 4.0 parts by mass of phenol resin foam powder as the foaming nucleating agent.

[0079] The density and closed-cell ratio of the phenolic resin foam were measured using the method described later, and the density was found to be 29 kg / m³. 3 The closed-cell ratio was 94%.

[0080] <Manufacturing of composites> Next, Rimquick 15 main agent (manufactured by Tama Waterproofing Technology Co., Ltd.) was heated separately to approximately 60°C as the first agent, and Rimquick 15 curing agent (manufactured by Tama Waterproofing Technology Co., Ltd.), which has an amino group to hydroxyl group ratio of 80:20, was heated to approximately 60°C to reduce its viscosity to 100 mP·s. The two were then pumped at a volume ratio of 1:1 through a hose heated to the same temperature to a spray gun at 10 MPa, where they were mixed at the tip of the gun and spray-coated to obtain a composite in which a polyurea urethane layer with a thickness of 0.5 mm was formed on the entire surface of the phenolic resin foam.

[0081] <Closed cell ratio of phenolic resin foam> The closed-cell ratio of phenolic resin foam was measured according to ASTM-D-2856 (Method C). Specifically, the polyurea layer or polyurea-urethane layer was removed from the composite, and the surface material was removed from the phenolic resin foam. Then, cylindrical samples with a diameter of 35 mm to 36 mm were drilled out using a cork borer, and the sample volume was measured using an air-comparative hydrometer (Tokyo Science Co., Ltd., Model 1,000). The volume of the walls (parts other than bubbles and voids) was calculated from the sample mass and the density of the cured phenolic resin. The apparent volume was also calculated from the external dimensions of the sample. The closed-cell ratio was then calculated by dividing the value obtained by subtracting the wall volume from the sample volume by the apparent volume. Here, the density of the phenolic resin was assumed to be 1.3 kg / L.

[0082] <Thermal conductivity of composite materials> In accordance with JIS A 1412-2:1999, the thermal conductivity in the thickness direction of the composite material was measured at a temperature of 23°C using the following method. The specific procedure is as follows. A 300mm square composite specimen was prepared, and the specimen was placed in an atmosphere of 23±1℃ and 50±2% humidity. Subsequently, the change in weight over time was measured every 24 hours, and the condition was checked and adjusted until the weight change after 24 hours was 0.2 mass% or less. The conditioned composite specimen was then introduced into a thermal conductivity measuring device placed in the same atmosphere of 23±1℃ and 50±2% humidity. If the thermal conductivity measuring device was not located in a controlled room of 23±1% and 50±2% humidity as the composite specimen was placed, the specimen, which had been checked and adjusted in the aforementioned atmosphere, was quickly placed in a polyethylene bag, sealed, and removed within one hour, and its thermal conductivity was immediately measured. Thermal conductivity measurements were performed using a single test specimen and a measurement device (Eiko Seiki Co., Ltd., product name "HC-074 / FOX304"), under conditions of 13°C for the low-temperature plate and 33°C for the high-temperature plate.

[0083] <Compressive strength of composite> The stress at fracture of the composite material was measured using the following method under ambient temperature of 23±2°C and ambient humidity of 50±5%. Test specimens were prepared by cutting phenolic resin foam into 100 mm squares and coating the surface with a polyurea layer or a polyurea urethane layer. The width, length, and thickness of each test specimen were measured using calipers specified in JIS K 7248 or JIS B 7507. A Shimadzu Autograph AG-20kNXD compression tester and a 20kN load cell were used. After conditioning the test specimens for 48 hours or more under an ambient temperature of 23±2℃ and ambient humidity of 50±5%, they were set in the compression tester and measured from the top surface of the specimen with an initial load of 20N and a compression speed of 20 mm / min. The deformation at the initial 20N compression was set to 0, and the load at which the specimen fractured was measured. For each test specimen, the compressive stress (N / cm²) was calculated by dividing the measured load value by the area. 2 After calculating the ), the average value of the measurement results for the five samples was calculated.

[0084] <Density of the complex> Test specimens were prepared by cutting phenolic resin foam into 100 mm squares and coating the surface with a polyurea layer or a polyurea-urethane layer. The width, length, and thickness of each test specimen were measured using calipers specified in JIS K 7248 or JIS B 7507. The density was calculated from the weight and volume of the test specimens.

[0085] <Moisture permeability of composite materials> The moisture permeability of the composite material was measured under conditions of 25°C and 90% RH using the following method. Specifically, a foam laminate was cut into 300 mm squares, and a polyurea layer or polyurea-urethane layer was coated on the surface to create a test specimen. The specimen was placed in an atmosphere of 23±1°C and 50±2% humidity. Subsequently, the change in weight over time was measured every 24 hours, and the condition was checked and adjusted until the weight change after 24 hours was 0.2% by mass or less. The conditioned composite specimen was left standing at 25°C and 90% RH for 24 hours, and the moisture permeability was defined as the value of the weight change divided by the surface area of ​​the specimen.

[0086] (Examples 2-3) As shown in Table 1, the composite was manufactured in the same manner as in Example 1, except that the thickness of the polyurea urethane layer was changed.

[0087] (Example 4) A composite was manufactured in the same manner as in Example 1, except that the top and bottom surfaces in the thickness direction of the phenolic resin foam were not coated with a polyurea urethane layer, and all four side surfaces in the thickness direction were coated with a polyurea urethane layer.

[0088] (Example 5) A composite was manufactured in the same manner as in Example 1, except that the top and bottom surfaces in the thickness direction of the phenolic resin foam and two opposing surfaces out of the four side surfaces in the thickness direction were not covered with the polyurea urethane layer, while two opposing side surfaces were covered with the polyurea urethane layer.

[0089] (Example 6) A composite was prepared in the same manner as in Example 1, except that a curing agent with an amino group to hydroxyl group ratio of 100:0 was used as the second agent, in which a polyurea layer with a thickness of 0.5 mm was formed on the entire surface of the phenolic resin foam.

[0090] (Example 7) A composite was prepared in the same manner as in Example 1, except that a curing agent with an amino group to hydroxyl group ratio of 70:30 was used as the second agent, in which a polyurea urethane layer with a thickness of 0.5 mm was formed on the entire surface of the phenolic resin foam.

[0091] (Comparative Example 1) A phenolic resin foam was obtained in the same manner as in Example 1, except that the surface of the phenolic resin foam was not coated at all with a polyurea urethane layer.

[0092] Thermal conductivity, compressive strength, density, and compressive strength / density were measured for the composites of Examples 1-7 and the phenolic resin foam of Comparative Example 1. The results are shown in Table 1. In addition, the arrangement and thickness of the polyurea layer or polyurea-urethane layer of the composites of the examples are summarized in Table 1.

[0093] [Table 1]

Claims

1. A composite of a phenolic resin foam and a polyurea urethane layer, All surfaces of the phenolic resin foam are covered with the polyurea urethane layer. The thickness of the aforementioned polyurea urethane layer is 0.2 mm or more and 5.0 mm or less. A composite in which the ratio of the number of urethane bonds to the total number of urea bonds and urethane bonds in the polyurea-urethane layer is greater than 0% and less than or equal to 30%.

2. All surfaces of the phenolic resin foam are covered with the polyurea urethane layer, and the moisture permeability of the composite at 25°C and 90% RH is 7 g / (m²). ２ - The temperature is 24 hours or less, and the thermal conductivity is 0.016 W / (m·K) or more and 0.023 W / (m·K) or less. The thickness of the aforementioned polyurea urethane layer is 0.2 mm or more and 1.5 mm or less. The composite according to claim 1, wherein the ratio of the number of urethane bonds to the total number of urea bonds and urethane bonds in the polyurea urethane layer is 10% or more and 20% or less.

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