Soundproof polyurethane foam

Abstract

To provide a technology that can achieve sufficient sound insulation even with a single layer of polyurethane foam. [Solution] This technology provides a soundproof polyurethane foam obtained from a composition containing a polyol and a polyisocyanate, with a density of 140 kg / m³. 3 The above 10% hardness measured in accordance with JIS K6400-2:2012 is 1000 N / m. 2 The above measurement, in accordance with JIS K6400-7:2012, shows a ventilation of 4.0 cm. 3 / cm 2 We provide a soundproof polyurethane foam with a noise level of less than / sec.

Description

[Technical Field]

[0001] This technology relates to soundproof polyurethane foam. [Background technology]

[0002] Polyurethane foam soundproofing materials are widely used in the construction and transportation sectors, including vehicles and aircraft. For example, in the automotive sector, soundproofing materials are used to reduce noise generated from engines and other components. In recent years, various technological advancements have been made to soundproofing materials to suit their specific applications.

[0003] For example, Patent Document 1 discloses a soundproofing and vibration-damping material for vehicles, which is made of a soft polyurethane foam obtained by reacting and foaming an organic polyisocyanate component and a polyol component, wherein the organic polyisocyanate component mainly consists of monomeric MDI containing diphenylmethane diisocyanate together with its carbodiimide modified form and / or its uretonimine modified form, with an NCO content of 29-33%, and 2,4'-diphenylmethane diisocyanate is contained in the monomer and / or modified form component at a ratio of 1-45% by weight in the monomeric MDI, while the polyol component contains a polyol with 2-8 functional groups and a molecular weight of 1000-10000 at a ratio of 50% by weight or more, thereby achieving both excellent flame retardancy and excellent heat degradation resistance, as well as improved sound absorption characteristics and cost reduction.

[0004] In addition, Patent Document 2 discloses a flame-retardant soundproof material for vehicles comprising a polyurethane foam obtained by foam molding a urethane resin composition. The urethane resin composition has (A) an isocyanate component, (B) a polyol component, (C) a flame-retardant plasticizer, and (D) an antioxidant. The (A) isocyanate component has a mixture of 2,4'-diphenylmethane diisocyanate and 4,4'-diphenylmethane diisocyanate, and one or more modified products selected from at least one carbodiimide-modified product and uretonimine-modified product of the mixture. Thus, a flame-retardant soundproof material for vehicles having desired rigidity and flame retardancy in addition to soundproofing is disclosed.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0006] In recent years, with the spread of electric vehicles, hybrid vehicles, etc., the requirements for soundproofing mechanisms are also changing. For example, in the vehicle field, there are more noise sources on the higher frequency side in electric vehicles compared to gasoline vehicles. More specifically, in electric vehicles, since there is no engine noise, the noise from motors, compressors, etc. becomes prominent, and a soundproofing mechanism suitable for the noise emitted from motors and compressors is required.

[0007] In response to such a situation, in conventional soundproof materials using polyurethane foam, a sufficient soundproofing effect cannot be obtained, and a method of achieving the required soundproofing function by making a double structure of polyurethane foam and a resin cover, etc. has been common.

[0008] Therefore, the main object of the present technology is to provide a technology that can exhibit a sufficient sound insulation function even with a single layer of polyurethane foam.

Means for Solving the Problems

[0009] As a result of intensive research on the sound insulation function of polyurethane foam in a higher frequency range, the inventor of the present application found that by controlling the density, hardness, and ventilation of the polyurethane foam within a certain range, a difference occurs in the sound insulation function in the high frequency range, and thus the present technology was completed. That is, in the present technology, first, a sound insulation polyurethane foam obtained from a composition containing a polyol and a polyisocyanate, having a density of 140 kg / m 3 or more, a 10% hardness measured in accordance with JIS K6400-2:2012 of 1000 N / m 2 or more, ventilation measured in accordance with JIS K6400-7:2012 of 4.0 cm 3 / cm 2 / sec or less, is provided. The density of the sound insulation polyurethane foam according to the present technology may be 160 kg / m 3 or more. In the composition for obtaining the sound insulation polyurethane foam according to the present technology, the content of polymer polyol in 100 parts by mass of the polyol can be 5 parts by mass or less. In the composition for obtaining the sound insulation polyurethane foam according to the present technology, the content of carbodiimide-modified product in 100 parts by mass of the polyisocyanate can be 10 parts by mass or less. In the sound insulation polyurethane foam according to the present technology, the flame retardancy grade measured in accordance with the UL94 vertical flammability test in the state after heat aging at 135°C for 600 hours is V-2 or higher, and the flame retardancy grade measured in accordance with the UL94 horizontal flammability test may be HB.

Brief Description of the Drawings

[0010] [Figure 1] It is a graph showing the measurement results of the reverberation box transmission loss in the examples.

Mode for Carrying Out the Invention

[0011] Hereinafter, preferred embodiments for implementing the present technology will be described. The embodiments described below show an example of a typical embodiment of the present technology, and any of the embodiments can be combined. Also, the scope of the present technology is not construed narrowly by these.

[0012] 1. Soundproof polyurethane foam Hereinafter, the physical properties and the like of the soundproof polyurethane foam according to the present technology will be described in detail.

[0013] (1) Density The density of the soundproof polyurethane foam according to the present technology is 140 kg / m 3 or more. The density of the soundproof polyurethane foam according to the present technology is 140 kg / m 3 Within the range of or more, it can be freely set as long as the functions and effects of the present technology are not impaired.

[0014] The lower limit value of the density of the soundproof polyurethane foam according to the present technology is preferably 160 kg / m 3 or more, more preferably 170 kg / m 3 or more, still more preferably 180 kg / m 3 or more. By setting the lower limit value of the density of the polyurethane foam within this range, the soundproof effect in the high frequency range can be further improved.

[0015] The upper limit value of the density of the soundproof polyurethane foam according to the present technology is, for example, 220 kg / m 3 or less, preferably 210 kg / m 3 or less, more preferably 200 kg / m 3The following is the explanation: By setting the upper limit of the polyurethane foam density within this range, it is possible to provide cushioning without compromising the flexibility of the polyurethane foam (preventing it from becoming rigid).

[0016] In this technology, the density is the value measured by the method described in the examples below.

[0017] (2) 10% hardness The 10% hardness of the soundproof polyurethane foam related to this technology is 1000 N / m 2 The above is a characteristic feature. The 10% hardness of the soundproof polyurethane foam related to this technology is 1000 N / m 2 Within the above range, the settings can be freely determined as long as they do not impair the function or effect of this technology.

[0018] The lower limit of the 10% hardness of the sound-insulating polyurethane foam related to this technology is preferably 1100 N / m 2 More preferably 1200 N / m 2 More preferably, 1300 N / m 2 More preferably, 1400 N / m 2 In particular, 1500 N / m is preferred. 2 That concludes the explanation. By setting the lower limit of the 10% hardness of polyurethane foam within this range, the sound insulation effect in the high-frequency range can be further improved.

[0019] The upper limit of the 10% hardness of the polyurethane foam related to this technology is, for example, 2700 N / m². 2 Preferably, the following is 2600 N / m 2 More specifically, 2500 N / m 2 More preferably, 2400 N / m 2 The following applies:

[0020] In this technology, the 10% hardness is the value measured by the method described in the examples below.

[0021] (3) Ventilation The ventilation of the soundproof polyurethane foam related to this technology is 4.0 cm. 3 / cm 2 It is characterized by being less than or equal to / sec. The ventilation of the soundproof polyurethane foam related to this technology is 4.0cm 3 / cm 2 Within a range of / sec or less, the value can be freely set as long as it does not impair the function or effect of this technology.

[0022] The upper limit of the breathability of the soundproof polyurethane foam related to this technology is preferably 3.5 cm. 3 / cm 2 / sec or less, more preferably 3.2cm 3 / cm 2 / sec or less, more preferably 3.0cm 3 / cm 2 The value is less than / sec. The lower limit of ventilation for the soundproof polyurethane foam related to this technology is, for example, 0.01 cm. 3 / cm 2 / sec or more, preferably 0.1cm 3 / cm 2 / sec or more, more preferably 0.2cm 3 / cm 2 / sec or more, more preferably 0.3cm 3 / cm 2 The value is 1 / sec or higher. By ensuring the ventilation of the polyurethane foam is within this range, the soundproofing effect in the high-frequency range can be further improved.

[0023] (4) Sound insulation performance The soundproof polyurethane foam according to this technology is characterized by its high soundproofing effect in the high-frequency range. Therefore, it can exhibit sufficient soundproofing effect without the need for a multi-layer structure with a resin cover or the like, as in conventional soundproofing materials, and can also contribute to reducing manufacturing time and costs. Specifically, for example, the reverberation chamber transmission loss at 2000 Hz is, for example, 40.0 dB or more, preferably 40.1 dB or more, more preferably 40.2 dB or more, even more preferably 40.4 dB or more, even more preferably 40.5 dB or more, and particularly preferably 41.0 dB or more.

[0024] In this technology, the reverberation chamber transmission loss is the value measured by the method described in the examples below.

[0025] (5) Flame retardant properties The flame retardancy of the soundproof polyurethane foam related to this technology is not particularly limited, but to broaden the range of applications, it is preferable to have high flame retardancy. Specifically, it is preferable that the flame retardancy grade measured in accordance with the UL94 vertical flammability test is V-2 or higher, and that the flame retardancy grade measured in accordance with the UL94 horizontal flammability test is HB.

[0026] Furthermore, it is preferable that the soundproof polyurethane foam related to this technology maintains a certain level of flame retardancy even after thermal aging in high-temperature environments such as vehicle engine compartments. Specifically, it is preferable that the flame retardancy grade measured in accordance with the UL94 horizontal flame retardancy test after thermal aging is V-2 or higher, and that the flame retardancy grade measured in accordance with the UL94 horizontal flame retardancy test is HB. The thermal aging conditions are described in the examples described later.

[0027] (6) Tensile strength The tensile strength of the soundproof polyurethane foam according to this technology can be freely set as long as it does not impair the function or effect of this technology. The lower limit of the tensile strength of the soundproof polyurethane foam according to this technology is, for example, 100 kPa or more, preferably 150 kPa or more, more preferably 200 kPa or more, even more preferably 250 kPa or more, and even more preferably 300 kPa or more. There is no particular upper limit to the tensile strength of the polyurethane foam according to this technology, but for example, it is 1000 kPa or less.

[0028] Furthermore, it is preferable that the sound-insulating polyurethane foam related to this technology maintains a certain level of tensile strength even after thermal aging in high-temperature environments such as the engine compartment of a vehicle.

[0029] In this technology, the tensile strength is the value measured by the method described in the examples below.

[0030] 2. Composition for manufacturing soundproof polyurethane foam The soundproof polyurethane foam according to this technology is manufactured using a composition containing a polyol and a polyisocyanate. The composition used in the manufacture of the soundproof polyurethane foam according to this technology may also contain, as necessary, crosslinking agents, foaming agents, catalysts, foam stabilizers, etc. Each component will be described in detail below.

[0031] (1) Polyol The polyols that can be used in this technology can be freely selected from one or more types of polyols that can be used in the manufacture of polyurethane foam, as long as they do not impair the purpose or effects of this technology. Examples include polyether polyols, polyester polyols, polycarbonate polyols, polyester ether polyols, polymer polyols, and the like.

[0032] Examples of polyether polyols include polyethylene glycol, polypropylene glycol, polytetramethylene ether glycol, and their copolyethers, which are obtained by polymerizing cyclic ethers such as ethylene oxide (EO), propylene oxide (PO), and tetrahydrofuran as initiators. They can also be obtained by polymerizing the above-mentioned cyclic ethers using polyhydric alcohols such as glycerin and trimethylolethane.

[0033] Examples of polyester polyols include aliphatic dicarboxylic acids such as succinic acid, adipic acid, sebacic acid, and azelaic acid; aliphatic carboxylic acids such as ricinoleic acid; aromatic dicarboxylic acids such as phthalic acid, terephthalic acid, isophthalic acid, and naphthalenedicarboxylic acid; alicyclic dicarboxylic acids such as hexahydrophthalic acid, hexahydroterephthalic acid, and hexahydroisophthalic acid; or acid esters or acid anhydrides thereof, and ethylene glycol, 1,3-propylene glycol, 1,2-propylene glycol, and 1,3-butylene glycol. Examples of polyester polyols include polypropylene glycol obtained by dehydration condensation reactions with polynediols such as 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 3-methyl-1,5-pentanediol, neopentyl glycol, 1,8-octanediol, 1,9-nonanediol, or mixtures thereof; and polylactone polyols and polycaprolactone polyols obtained by ring-opening polymerization of lactone monomers such as ε-caprolactone and methylvalerolactone. In addition to these, examples of polyester polyols include polyols having naturally derived ester groups.

[0034] Examples of polycarbonate polyols include those obtained by reacting at least one polyhydric alcohol, such as ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 3-methyl-1,5-pentanediol, neopentyl glycol, 1,8-octanediol, 1,9-nonanediol, or diethylene glycol, with diethylene carbonate, dimethyl carbonate, diethyl carbonate, or the like.

[0035] Examples of polyester ether polyols include aliphatic dicarboxylic acids such as succinic acid, adipic acid, sebacic acid, and azelaic acid; aromatic dicarboxylic acids such as phthalic acid, terephthalic acid, isophthalic acid, and naphthalenedicarboxylic acid; alicyclic dicarboxylic acids such as hexahydrophthalic acid, hexahydroterephthalic acid, and hexahydroisophthalic acid; or those obtained by dehydration condensation reactions of these acid esters or acid anhydrides with glycols such as diethylene glycol or propylene oxide adducts, or mixtures thereof.

[0036] Polymer polyols are those obtained by polymerizing ethylenically unsaturated monomers in a polyol, or by emulsifying and dispersing polymers of ethylenically unsaturated monomers in a polyol. Specifically, examples include those obtained by graft polymerization of acrylonitrile, styrene, etc., into a polyol, or those obtained by dispersing polystyrene or polyacrylonitrile in a polyol.

[0037] In this technology, the polyols described above can be freely combined and used, but it is preferable to set the content of polymer polyol in 100 parts by mass of polyol to 5 parts by mass or less. By setting the content of polymer polyol in 100 parts by mass of polyol to 5 parts by mass or less, the flame retardant performance of the manufactured polyurethane foam can be further improved. The lower the content of polymer polyol in 100 parts by mass of polyol, the better the flame retardant performance, so it is preferable to have 4 parts by mass or less, more preferably 3 parts by mass or less, even more preferably 2 parts by mass or less, even more preferably 1 part by mass or less, and particularly preferable to have 0 parts by mass.

[0038] (2) Polyisocyanates The polyisocyanates that can be used in this technology are one or more polyisocyanates that can be used in the manufacture of polyurethane foam, as long as they do not impair the purpose and effects of this technology. For example, aromatic isocyanates such as diphenylmethane diisocyanate (MDI), polymethylene polyphenyl polyisocyanate (polymeric MDI), toluene diisocyanate (TDI), naphthalene diisocyanate, and xylylene diisocyanate; aliphatic isocyanates such as hexamethylene diisocyanate, isophorone diisocyanate, and dicyclohexylmethane diisocyanate; and modified polyisocyanates obtained by modifying these. Among these, in this technology, it is preferable to use aromatic isocyanates as the isocyanate, and it is more preferable to use diphenylmethane diisocyanate (MDI) and polymethylene polyphenyl polyisocyanate (polymeric MDI).

[0039] In this technology, the isocyanates described above can be freely combined and used, but it is preferable to set the content of the carbodiimide modified material in 100 parts by mass of isocyanate to 10 parts by mass or less. By setting the content of the carbodiimide modified material in 100 parts by mass of isocyanate to 10 parts by mass or less, the flame retardant performance of the manufactured polyurethane foam can be further improved. The lower the content of the carbodiimide modified material in 100 parts by mass of isocyanate, the better the flame retardant performance, so it is preferable to have 7 parts by mass or less, more preferably 5 parts by mass or less, even more preferably 3 parts by mass or less, even more preferably 1 part by mass or less, and particularly preferable to have 0 parts by mass.

[0040] The isocyanate index of the polyurethane foam is not particularly limited, as long as it does not impair the function or effect of this technology. In this technology, the lower limit of the isocyanate index is, for example, 80 or higher, preferably 85 or higher, and more preferably 90 or higher. By setting the lower limit of the isocyanate index within this range, the strength of the polyurethane foam produced can be improved.

[0041] The upper limit of the isocyanate index is, for example, 120 or less, preferably 115 or less, and more preferably 110 or less. By setting the upper limit of the isocyanate index within this range, it is possible to prevent the polyurethane foam from becoming too hard, brittle, and losing its flexibility, and to improve the elasticity of the polyurethane foam.

[0042] In this technology, the isocyanate index is calculated using the formula [(Isocyanate equivalent in the polyurethane foam manufacturing composition / Equivalent of active hydrogen in the polyurethane foam manufacturing composition) × 100].

[0043] (3) Crosslinking agent A crosslinking agent can be used in the manufacture of the soundproof polyurethane foam related to this technology. As long as the purpose and effects of this technology are not impaired, one or more crosslinking agents that can be used in the manufacture of polyurethane foam can be freely selected and used.

[0044] Examples of crosslinking agents include ethylene glycol, diethanolamine, dipropylene glycol, 1,3-propanediol, 1,4-butanediol, 2-methyl-1,3-propanediol, diethylene glycol, propylene glycol, glycerin, trimethylolpropane, 1,2,4-butanetriol, 2-methyl-2,3,4-butanetriol, triethanolamine, pentaerythritol, and the like.

[0045] The amount of crosslinking agent in the composition used to manufacture the soundproof polyurethane foam according to this technology can be freely set as long as it does not impair the purpose and effect of this technology. In this technology, the lower limit of the crosslinking agent content in the composition is, for example, 1.0 part by mass or more, preferably 2.0 parts by mass or more, and more preferably 2.5 parts by mass or more, per 100 parts by mass of polyol. By setting the lower limit of the crosslinking agent content in the composition within this range, the resinification reaction is promoted, and a polyurethane foam with appropriate hardness can be manufactured.

[0046] The upper limit of the crosslinking agent content in the composition is, for example, 15 parts by mass or less, preferably 12 parts by mass or less, and more preferably 10 parts by mass or less, per 100 parts by mass of polyol. By setting the upper limit of the crosslinking agent content in the composition within this range, destabilization of the resinification reaction can be prevented. As a result, polyurethane foam with excellent mechanical properties and appearance can be obtained.

[0047] (4) Foaming agent A blowing agent can be used in the manufacture of the soundproof polyurethane foam related to this technology. As for the blowing agent that can be used in this technology, one or more types of blowing agents that can be used in the manufacture of polyurethane foam can be freely selected and used, as long as they do not impair the purpose or effect of this technology.

[0048] Examples of foaming agents include water, hydrocarbons, and halogenated compounds. Examples of hydrocarbons include cyclopentane, isopentane, and n-pentane. Examples of halogenated compounds include methylene chloride, trichlorofluoromethane, dichlorodifluoromethane, nonafluorobutyl methyl ether, nonafluorobutyl ethyl ether, pentafluoroethyl methyl ether, and heptafluoroisopropyl methyl ether. In this technology, water is preferred as the foaming agent among these. The water may be deionized water, tap water, or distilled water.

[0049] The amount of foaming agent used in the production of polyurethane foam according to this technology can be freely set as long as it does not impair the function or effect of this technology. In this technology, the lower limit of the foaming agent content in the composition is, for example, 0.1 parts by mass or more, preferably 0.5 parts by mass or more, and more preferably 1 part by mass or more, per 100 parts by mass of polyol. By setting the lower limit of the foaming agent content in the composition within this range, foamability can be improved, and as a result, polyurethane foam with excellent mechanical properties and appearance can be obtained.

[0050] In this technology, the upper limit of the foaming agent content in the composition is, for example, 10 parts by mass or less, preferably 7 parts by mass or less, and more preferably 5 parts by mass or less, per 100 parts by mass of polyol. By setting the upper limit of the foaming agent content in the composition within this range, it is possible to suppress formation defects due to excessive foaming.

[0051] (5) Catalyst A catalyst can be used in the production of polyurethane foam according to this technology. As for the catalyst that can be used in this technology, one or more catalysts that can be used in the production of polyurethane foam can be freely selected and used, as long as they do not impair the action or effect of this technology.

[0052] Examples of catalysts include triethylenediamine (TEDA), bis(2-dimethylaminoethyl) ether, triethylamine, tetramethylguanidine, diethanolamine, N,N,N',N'',N''-pentamethyldiethylenetriamine, imidazole compounds, piperazine amines such as N,N'-dimethylpiperazine, N,N',N'-trimethylaminoethylpiperazine, N-methyl-N'-(2-dimethylamino)ethylpiperazine, and N-methyl-N'-(2-hydroxyethyl)piperazine, morpholine amines such as N-methylmorpholine and N-ethylmorpholine, 1,8-diazabicyclo-[5,4,0]-undecene-7 (DBU), 1,5-diazabicyclo-[4,3,0]-nonene-5 (DBN), and 1,8-diazabicyclo Examples of metal catalysts (organometallic catalysts) include amines such as amines referred to as DBU congeners, such as chloro-[5,3,0]-decene-7 (DBD) and 1,4-diazabicyclo-[3,3,0]octene-4 (DBO), as well as organoiron compounds (iron acetylacetonate, etc.), organonickel compounds (nickel acetylacetonate, nickel octoate, nickel naphthenate, etc.), organotin compounds (tin octoate, tin 2-ethylhexanoate, etc.), organobismuth compounds (bismuth octoate, bismuth naphthenate, etc.), organolead compounds (lead octanoate, lead naphthenate, etc.), organocobalt compounds (cobalt acetylacetonate, cobalt octoate, cobalt naphthenate, etc.), organozirconium compounds (zirconium acetylacetonate, etc.), and organozinc compounds.

[0053] The amount of catalyst in the composition used to manufacture the soundproof polyurethane foam according to this technology can be freely set as long as it does not impair the function or effect of this technology. In this technology, the lower limit of the catalyst content in the composition is, for example, 0.1 parts by mass or more, preferably 0.5 parts by mass or more, and more preferably 1.0 part by mass or more, per 100 parts by mass of polyol. By setting the lower limit of the catalyst content in the composition within this range, various reactions during manufacturing can be controlled, and as a result, polyurethane foam with excellent mechanical properties and appearance can be obtained.

[0054] In this technology, the upper limit of the catalyst content in the composition is, for example, 10 parts by mass or less, preferably 5 parts by mass or less, and more preferably 3 parts by mass or less, per 100 parts by mass of polyol. By setting the upper limit of the catalyst content in the composition within this range, it is possible to prevent destabilization of various reactions during manufacturing. As a result, polyurethane foam with excellent mechanical properties and appearance can be obtained.

[0055] (6) Foam stabilizers A foam stabilizer can be used in the manufacturing of polyurethane foam related to this technology. By using a foam stabilizer, a higher quality polyurethane foam can be manufactured.

[0056] As foam stabilizers that can be used in this technology, one or more types of foam stabilizers that can be used in the manufacture of polyurethane foam may be freely selected and used, as long as they do not impair the function or effect of this technology. Examples include silicone-based foam stabilizers, fluorine-containing compound-based foam stabilizers, surfactants, etc. Examples of silicone-based foam stabilizers include those mainly composed of siloxane chains, those in which siloxane chains and polyether chains form a linear structure, those that are branched and separated, and those in which polyether chains are modified into a pendant-like structure of siloxane chains.

[0057] The amount of foam stabilizer in the composition used to manufacture the polyurethane foam according to this technology can be freely set as long as it does not impair the function or effect of this technology. The lower limit of the foam stabilizer content in the composition is, for example, 0.1 parts by mass or more, preferably 0.5 parts by mass or more, and more preferably 1 part by mass or more, per 100 parts by mass of polyol. The upper limit of the foam stabilizer content in the composition is, for example, 10 parts by mass or less, preferably 5 parts by mass or less, and more preferably 3 parts by mass or less, per 100 parts by mass of polyol.

[0058] (7) Others In the manufacture of polyurethane foam related to this technology, one or more components that can be used in the manufacture of polyurethane foam may be freely selected and used as other components, depending on the purpose, as long as they do not impair the function or effect of this technology.

[0059] Examples of components that can be used in the manufacture of polyurethane foam related to this technology include flame retardants, pigments, stabilizers, plasticizers, colorants, antibacterial agents, dispersants, fillers, antioxidants, and ultraviolet absorbers.

[0060] 3. Method for manufacturing soundproof polyurethane foam The soundproof polyurethane foam according to this technology can be manufactured by mixing the components of the aforementioned soundproof polyurethane foam manufacturing composition to prepare the composition, and then proceeding with the resinification reaction and foaming reaction. The resinification reaction and foaming reaction can be carried out using any combination of general methods, as long as they do not impair the function and effects of this technology.

[0061] The foaming method for the soundproof polyurethane foam according to this technology can employ any of the following methods: mold foaming, slab foaming, or batch foaming. Mold foaming is a method in which a polyurethane foam manufacturing composition (raw material for polyurethane foam) is mixed and injected into the cavity of a mold (molding die) and foamed into the shape of the cavity. Slab foaming is a method in which a polyurethane foam manufacturing composition (raw material for polyurethane foam) is mixed and cast onto a moving conveyor and foamed under atmospheric pressure and at room temperature. Batch foaming is a method in which a polyurethane foam manufacturing composition (raw material for polyurethane foam) is mixed and extruded into a foaming box and foamed under atmospheric pressure and at room temperature.

[0062] 4. Uses of soundproof polyurethane foam The soundproof polyurethane foam related to this technology can be used in any field and for any application where soundproofing is required, due to its high soundproofing effect. Furthermore, because the soundproof polyurethane foam related to this technology also has excellent flame retardancy, it can be used in any field and for any application where flame retardancy is required. For example, it can be suitably used in the construction field and in the transportation field such as vehicles and aircraft.

[0063] Furthermore, the soundproof polyurethane foam related to this technology also possesses high heat resistance and is resistant to thermal degradation, making it suitable for use in all fields and applications where heat resistance is required. For example, it can be suitably used as a soundproofing material around engines in the transportation sector, such as vehicles and aircraft.

[0064] Furthermore, this technology can be configured as follows: [1] A soundproof polyurethane foam obtained from a composition comprising a polyol and a polyisocyanate, Density is 140 kg / m³ 3 That's all. The 10% hardness measured according to JIS K6400-2:2012 is 1000 N / m. 2 That's all. The ventilation measured according to JIS K6400-7:2012 is 4.0 cm. 3 / cm 2 Soundproof polyurethane foam with a frequency of less than / sec. [2] Density is 160 kg / m³ 3 The above is the soundproof polyurethane foam described in [1]. [3] The soundproof polyurethane foam according to [1] or [2], wherein the content of polymer polyol in 100 parts by mass of the polyol in the composition is 5 parts by mass or less. [4] The soundproof polyurethane foam according to any one of [1] to [3], wherein the content of the carbodiimide modified material in 100 parts by mass of the polyisocyanate is 10 parts by mass or less. [5] A soundproof polyurethane foam as described in any of [1] to [4], wherein, after heat aging at 135°C for 600 hours, the flame retardancy grade measured in accordance with the UL94 vertical flammability test is V-2 or higher, and the flame retardancy grade measured in accordance with the UL94 horizontal flammability test is HB. [Examples]

[0065] The present technology will be described in more detail below based on the following examples. The examples described below are representative examples of the present technology and should not be interpreted as narrowing the scope of the present technology.

[0066] (1) Raw materials The raw materials used in this embodiment are as follows: Polyol 1: Polyether polyol (Hydroxyl value: 35, Molecular weight: 5000, Number of functional groups: 3) Polyol 2: Polymer polyol (Hydroxyl value: 28, Molecular weight: 5000, Number of functional groups: 3) Crosslinking agent 1: 1,2-ethanediol Crosslinking agent 2: Diethanolamine + Water Catalyst 1 (Foaming Catalyst): Bis(2-dimethylaminoethyl) ether Catalyst 2 (Resinization Catalyst): Triethylenediamine (TEDA) Catalyst 3 (Resinization Catalyst): Mixture of tertiary amine + ethylene glycol Catalyst 4 (Balanced Catalyst): Tertiary amine catalyst (TOYOCAT-D60 manufactured by Tosoh Corporation) Foam stabilizer: Silicone-based foam stabilizer Foaming agent: Water Polyisocyanate 1: Diphenylmethane diisocyanate (MDI) + Polymeric MDI (Dow Chemical Company's "SPECFLEX NE 426") Polyisocyanate 2:Carbodiimide-modified diphenylmethane diisocyanate (MDI), NCO% = 29.5%

[0067] (2) Manufacturing of polyurethane foam Each component except the isocyanate shown in Table 1 was mixed in the proportions shown in Table 1. The isocyanate was then added and mixed, and the mixture was injected into a 500mm x 500mm x 10mm or 20mm mold. The reaction was carried out at a mold temperature of 60°C. Depending on the reactivity, the mold clamps were partially opened 60 to 90 seconds after the raw materials were added to allow for degassing as needed. The mold was demolded 3 minutes after the raw materials were added to produce polyurethane foam.

[0068] (3) Measurement and evaluation of physical properties Physical properties and other characteristics were measured and evaluated 24 hours after the polyurethane foam was manufactured using the following method.

[0069] [Breathable] The air permeability of polyurethane foam manufactured using a 10 mm deep mold was measured according to a method compliant with JIS K6400-7:2012.

[0070] [Hardness] The 10% hardness of polyurethane foam manufactured using a 20mm deep mold was measured according to the method compliant with JIS K6400-2:2012.

[0071] [Transmission loss from reverberation chamber] A small reverberation box was installed inside an anechoic chamber. An opening was provided at the top of this small reverberation box, connecting the inside and outside (i.e., the anechoic chamber). A 1mm thick steel plate was installed to block this opening, and a 20mm deep sheet of polyurethane foam, manufactured using a mold, was placed on top of the steel plate. Noise with frequencies between 400 and 6300Hz was generated from inside the small reverberation box, and the difference in sound pressure levels between microphones mounted inside and outside the box was measured to calculate the transmission loss. For Comparative Example 1, the same measurements were also performed on a polyurethane foam with a 2mm thick thermoplastic polyurethane elastomer resin cover laminated on top.

[0072] [Heat resistance] The manufactured polyurethane foam was aged for 600 hours in a constant temperature bath at 135°C, and then its flame retardancy (vertical flammability test, horizontal flammability test) and tensile strength were measured using the following method.

[0073] [Flame retardant performance: Vertical flammability test] The flame retardancy was evaluated using a method compliant with the UL94 vertical flammability test. Specifically, a test specimen (127 mm long x 12.7 mm wide x 10 mm thick) cut from polyurethane foam after heat aging (conditions: 135°C, 600 hours) was mounted vertically on a clamp, and the burning time of the test specimen was measured by applying a 20 mm flame for 10 seconds twice. A burning time of 10 seconds or less was evaluated as ○, a burning time exceeding 10 seconds but 30 seconds or less as △, and a burning time exceeding 30 seconds as ×. In the flame retardancy grade measured according to the UL94 vertical flammability test, an evaluation of ○ corresponds to V-2.

[0074] [Flame retardant performance: Horizontal combustion test] The flame retardancy was evaluated using a method compliant with the UL94 horizontal flammability test. Specifically, a test specimen (127 mm long x 12.7 mm wide x 10 mm thick) cut from polyurethane foam after heat aging (conditions: 135°C, 600 hours) was mounted horizontally on a clamp, and a single 30-second indirect flame test with a 25 mm flame was performed to measure the burning rate of the test specimen. A burning rate of 38.1 mm / min or less was evaluated as ○, and a burning rate exceeding 38.1 mm / min was evaluated as ×. In terms of flame retardancy grade measured according to the UL94 horizontal flammability test, this corresponds to HB.

[0075] [Tensile strength] Tensile strength was measured for test specimens (dumbbell shape: length 120 mm x width MIN 10 mm ~ MAX 25 mm x thickness 10 mm) cut from polyurethane foam after heat aging (conditions: 135°C, 600 hours) using a method compliant with JIS K 6400-5. A measured tensile strength of 300 kPa or higher was evaluated as ○, and a tensile strength of 100 kPa or higher but less than 300 kPa was evaluated as △.

[0076] (4) Results The results are shown in Table 1 below. Figure 1 shows the measurement results for the reverberation chamber transmission loss. [Table 1]

[0077] (5) Discussion As shown in Table 1 and Figure 1, the density is 140 kg / m³ 3 In summary, the 10% hardness is 1000 N / m 2 In total, the ventilation is 4.0 cm. 3 / cm 2 The polyurethane foams of Examples 1-5, which had a sound insulation effect of less than / sec, had sound insulation effects equivalent to or better than conventional sound insulation materials with a two-layer structure of polyurethane foam and a resin cover (see the results for Comparative Example 1 + resin cover).

[0078] When comparing the examples, Example 1, which used a polymer polyol as the polyol, showed excellent sound insulation performance. However, Examples 2-5, which did not use a polymer polyol, showed higher flame retardancy performance (vertical flammability test and horizontal flammability test) after heat aging. Similarly, in Example 1, which used a carbodiimide modified polyisocyanate, Examples 2-5, which did not use a carbodiimide modified polyisocyanate, showed higher flame retardancy performance (vertical flammability test and horizontal flammability test) after heat aging.

[0079] Density is 160 kg / m³ 3 Compared to Example 2, which had a density of less than 160 kg / m³, this example has a density of 160 kg / m³. 3 Examples 3-5 described above showed superior soundproofing performance.

Claims

1. A soundproof polyurethane foam obtained from a composition comprising a polyol and a polyisocyanate, Density is 140 kg / m³ ３ That's all. The 10% hardness measured according to JIS K6400-2:2012 is 1000 N / m. ２ That's all. The ventilation measured according to JIS K6400-7:2012 is 4.0 cm. ３ / cm ２ Soundproof polyurethane foam with a temperature of / sec or less.

2. Density is 160 kg / m³ ３ The soundproof polyurethane foam described in claim 1 is as described above.

3. The soundproof polyurethane foam according to claim 1, wherein the content of polymer polyol in 100 parts by mass of the polyol in the composition is 5 parts by mass or less.

4. The soundproof polyurethane foam according to claim 1, wherein the content of the carbodiimide modified material in 100 parts by mass of the polyisocyanate is 10 parts by mass or less.

5. The soundproof polyurethane foam according to claim 1, wherein, after thermal aging at 135°C for 600 hours, the flame retardancy grade measured in accordance with the UL94 vertical flammability test is V-2 or higher, and the flame retardancy grade measured in accordance with the UL94 horizontal flammability test is HB.

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