Starting material composition for rigid isocyanurate foam, rigid isocyanurate foam and sound absorbing material

Abstract

Provided is a starting material composition suitable for producing a hard isocyanurate foam having excellent energy-absorbing performance and sound-absorbing performance while exhibiting excellent foam moldability, appearance, and air permeability. The starting material composition of the rigid isocyanurate foam according to the invention contains a polyol composition and a polyisocyanate. The polyol composition contains a trifunctional or higher functional polyether polyol (C) having a hydroxyl number of 300 mg KOH / g or more, a polyether polyol (A) different from the polyether polyol (C) having an ethylene oxide content of 50 mass% or more based on the total amount of alkylene oxides of the polyether polyol (A), and a polyether polyol (B) different from the polyether polyol (C), and a polyether polyol (B) having an ethylene oxide content of 10 mass% or less relative to the total amount of the alkylene oxides. The isocyanate index of the starting material composition is 105 or more and 400 or less. The content of the component (A) is 30-50 parts by mass (inclusive), and the content of the component (C) is 5-35 parts by mass (inclusive) per 100 parts by mass of the total amount of the starting material composition excluding the polyisocyanate.

Description

Technical Field

[0001] The present invention relates to a starting material composition of a rigid isocyanurate foam, a method for producing the rigid isocyanurate foam, the rigid isocyanurate foam and a sound absorbing material comprising the rigid isocyanurate foam. Background Art

[0002] Rigid isocyanurate foam is a resin foam obtained by reacting polyol and polyisocyanate, and is known to be a lightweight material having excellent mechanical properties. Rigid isocyanurate foam having these characteristics is very useful because it is used in various fields such as automobiles, construction, and civil engineering. Rigid isocyanurate foam has been actively improved from various perspectives to further enhance its functionality.

[0003] For example, PTL 1 discloses a rigid polyurethane foam composed of three layers: a surface high-density layer, an inner low-density layer, and a surface high-density layer to improve shock absorption and sound absorption performance. PTL 2 discloses a sound-absorbing impact absorber composed of a rigid polyisocyanurate foam formed of a specific polyol component and a specific polyisocyanate component.

[0004] Citation List

[0005] Patent Literature

[0006] PTL 1: JP2005-272806A

[0007] PTL 2: JP2013-47338A Summary of the invention

[0008] Technical issues

[0009] However, PTL 1 discloses that the rigid polyurethane foam has a compressive stress of 300 to 700 N at 10% to 60%. Assuming that the stress is a curve that increases with displacement, it is believed that the rigid polyurethane foam does not have sufficient energy absorption performance. The polyurethane foam disclosed in PTL 2 lacks the stability of the cells in the foam, and it is not necessarily possible to achieve both sound absorption performance and energy absorption performance at the same time, and there is still room for improvement.

[0010] In particular, there is a trade-off relationship between the vibration damping performance (energy absorption performance) and the sound absorption performance of rigid isocyanurate foam, and it is not easy to improve both performances at the same time. However, in many applications, both energy absorption performance and sound absorption performance are required; from this perspective, there is a strong demand for rigid isocyanurate foams that are excellent in both energy absorption performance and sound absorption performance.

[0011] The present invention is made in view of the above circumstances. An object of the present invention is to provide a starting material composition suitable for producing a rigid isocyanurate foam having excellent energy absorption and sound absorption properties and exhibiting excellent foam moldability, appearance and air permeability; and to provide a rigid isocyanurate foam and a sound absorbing material.

[0012] Problem Solution

[0013] The present inventors have conducted extensive studies to achieve the object, and have found that the object can be achieved by using a specific polyol composition and a specific polyisocyanate as essential components, and have completed the present invention.

[0014] Specifically, the present invention includes the subjects described in the following items, for example.

[0015] Project 1

[0016] A starting material composition for a rigid isocyanurate foam, the starting material composition comprising a polyol composition and a polyisocyanate,

[0017] The polyol composition comprises

[0018] a polyether polyol (A) having an ethylene oxide content of 50% by mass or more based on the total amount of alkylene oxides in the polyether polyol (A),

[0019] a polyether polyol (B) having an ethylene oxide content of 10% by mass or less based on the total amount of alkylene oxides in the polyether polyol (B), and

[0020] a trifunctional or higher-functional polyether polyol (C) having a hydroxyl value of 300 mg KOH / g or more,

[0021] in

[0022] The content of component (A) is 30 parts by mass or more and 50 parts by mass or less, and the content of component (C) is 5 parts by mass or more and 35 parts by mass or less, each based on 100 parts by mass of the total amount of the starting material composition excluding the polyisocyanate, and

[0023] The isocyanate index of the starting material composition is 105 or more and 400 or less.

[0024] Project 2

[0025] The starting material composition according to item 1, wherein the content of component (B) is 10 parts by mass or more and 15 parts by mass or less based on 100 parts by mass of the total amount of the starting material composition excluding the polyisocyanate.

[0026] Project 3

[0027] A method for producing a rigid isocyanurate foam, comprising the step of reacting the starting material composition according to item 1 or item 2.

[0028] Project 4

[0029] A rigid isocyanurate foam obtained by reacting the starting material composition of item 1 or item 2.

[0030] Project 5

[0031] A sound absorbing material comprising the rigid isocyanurate foam described in item 4.

[0032] Advantageous Effects of the Invention

[0033] The starting material composition of the rigid isocyanurate foam according to the present invention is suitable as a starting material for producing a rigid isocyanurate foam which is excellent in both energy absorption and sound absorption properties and exhibits excellent foam moldability, appearance and air permeability.

[0034] Implementation Description

[0035] The embodiments of the present invention will be described in detail below. In this specification, the terms "comprise", "contain" and "include" cover the concepts of "comprises", "consisting mainly of" and "consisting of".

[0036] 1. Starting material composition of rigid isocyanurate foam

[0037] The starting material composition of the rigid isocyanurate foam according to the present invention contains a polyol composition and a polyisocyanate. In this specification, the starting material composition of the rigid isocyanurate foam according to the present invention is hereinafter referred to as "the starting material composition of the present invention".

[0038] In the starting material composition of the present invention, the polyol composition contains a trifunctional or higher-functional polyether polyol (C) having a hydroxyl value of 300 mg KOH / g or more, a polyether polyol (A) different from the polyol (C) having an ethylene oxide content of 50% by mass or more based on the total amount of alkylene oxides of the polyether polyol (A), and a polyether polyol (B) different from the polyol (C) having an ethylene oxide content of 10% by mass or less based on the total amount of alkylene oxides of the polyether polyol (B).

[0039] In the starting material composition of the present invention, the content of component (A) is 30 parts by mass or more and 50 parts by mass or less, and the content of component (C) is 5 parts by mass or more and 35 parts by mass or less, each based on 100 parts by mass of the total amount of the starting material composition other than the polyisocyanate. The isocyanate index of the starting material composition of the present invention is 105 or more and 400 or less. The phrase "the total amount of the starting material composition other than the polyisocyanate" refers to the total amount of all components other than the polyisocyanate in the starting material composition of the present invention.

[0040] Due to the polyol composition and the polyisocyanate, the starting material composition of the present invention can produce a rigid isocyanurate foam having excellent energy absorption and sound absorption properties, and exhibiting excellent foam moldability, appearance and air permeability. Specifically, the starting material composition of the present invention is suitable as a starting material for producing a rigid isocyanurate foam having excellent energy absorption and sound absorption properties.

[0041] Polyol composition

[0042] As described above, the polyol composition contains a trifunctional or higher functional polyether polyol (C) having a hydroxyl value of 300 mg KOH / g or more, a polyether polyol (A) different from the polyol (C) having an ethylene oxide content of 50% by mass or more based on the total amount of alkylene oxides of the polyether polyol (A), and a polyether polyol (B) different from the polyol (C) having an ethylene oxide content of 10% by mass or less based on the total amount of alkylene oxides of the polyether polyol (B). In the present specification, these components are referred to as "component (C)", "component (A)" and "component (B)", respectively. The ethylene oxide content in a more precise sense refers to the content of structural units derived from ethylene oxide based on the total content of structural units derived from alkylene oxide, and refers to the content of structural units formed by polymerization of ethylene oxide.

[0043] Component (A) is a polyether polyol compound having an ethylene oxide unit content of 50% by mass or more, based on the total amount of alkylene oxides of the polyether polyol (A). Component (A) more preferably has an ethylene oxide unit content of 60% by mass or more, still more preferably 70% by mass or more, and particularly preferably 90% by mass or less, based on the total amount of alkylene oxides of the polyether polyol (A). In the context of the present invention, unless otherwise specified, the content of a specific alkylene oxide of a specific polyol is understood to be based on the total amount of alkylene oxides of the specific polyol.

[0044] Component (A) may contain one or more additional structural units other than ethylene oxide units, as long as component (A) has an ethylene oxide unit content of 50% by mass or more based on the total amount of alkylene oxide of the polyether polyol (A). These additional structural units can be selected from the structural units contained in a wide range of conventional rigid isocyanurate foams. Examples include structural units derived from various cyclic ethers such as alkylene oxides containing 3 or more carbon atoms and styrene oxide. The cyclic ether can be, for example, a cyclic ether described below, and a specific example is a propylene oxide unit. For example, component (A) can be a polyether polyol compound containing ethylene oxide units and propylene oxide units. Component (A) may also contain structural units derived from polyols described below.

[0045] The average active hydrogen number (f) of component (A) is preferably 2 or more, more preferably 3 or more, and more preferably 5 or less. An example of the active hydrogen of component (A) is a hydroxyl group.

[0046] In this specification, the average number of active hydrogens refers to the number of active hydrogens per molecule, in particular the number of hydroxyl groups per molecule. The average number of active hydrogens can be controlled by the number of active hydrogens of the initiator used in the synthesis. The average number of active hydrogens (f) can be determined from the hydroxyl value (OHV) and the number average molecular weight (Mn) of the polyol according to the following formula:

[0047] Average active hydrogen number (f) = Mn (g / mol) × OHV (mg KOH / g) / 56100

[0048] Component (A) has a hydroxyl value of preferably less than 300 mg KOH / g, more preferably from 7 to 87 mg KOH / g, and most preferably from 17 to 57 mg KOH / g.

[0049] In this specification, the hydroxyl value refers to the value in milligrams of potassium hydroxide required to neutralize the free hydroxyl groups (in 1 gram of sample) completely acetylated with acetic anhydride, and refers to the value measured according to JIS K1557 (2007). Specifically, the method for determining the hydroxyl value is as follows. The hydroxyl groups in the sample are acetylated with acetic anhydride, and the acetic anhydride that does not participate in the acetylation is titrated with a potassium hydroxide ethanol solution. The result is applicable to the following formula:

[0050] Hydroxyl value (mg KOH / g) = [((AB) × f × 28.05) / S] + acid value

[0051] (A represents the amount (mL) of 0.5 mol / L potassium hydroxide ethanol solution used in the blank test, B represents the amount (mL) of 0.5 mol / L potassium hydroxide ethanol solution used in the titration, f represents the coefficient 0.5 (the coefficient of 0.5N sodium hydroxide solution), and S represents the collected sample amount (g)).

[0052] The mass average molecular weight (Mw) of component (A) is not particularly limited, and, for example, it may be within the same range as the polyether polyol compound used to produce conventional rigid isocyanurate foams. For example, the mass average molecular weight (Mw) of component (A) is preferably 1000 or more and 10000 or less. The mass average molecular weight (Mw) used in this specification (which is also referred to as "weight average molecular weight") is one of the average molecular weights of synthetic polymers. If the molecular weight of component i contained in the polymer is Mi, the weight fraction is wi, and the number of molecules is Ni, the mass average molecular weight ∑Miwi is determined according to the following formula.

[0053] ∑Miwi=ΣMi 2 Ni / ΣMiNi

[0054] Specifically, the mass average molecular weight refers to the sum of the molecular weights of the polymer components multiplied by their weight fractions. The mass average molecular weight can be measured by gel permeation chromatography (GPC).

[0055] Component (A) contained in the polyol composition may be of a single type, or of two or more types, i.e., may be composed of one polyether polyol or two or more different polyether polyols, in which case each polyether polyol of component (A) has an ethylene oxide unit content of 50% by mass or more based on the total amount of alkylene oxides of the corresponding polyether polyol of component (A).

[0056] Component (B) is a polyether polyol compound having an ethylene oxide unit content of 10% by mass or less based on the total amount of alkylene oxides of the polyether polyol (B). Component (B) preferably has an ethylene oxide unit content of 5% by mass or less, and more preferably 1% by mass or less, based on the total amount of alkylene oxides of the polyether polyol (B). Component (B) may also have an ethylene oxide unit content of 0% by mass, that is, component (B) may not contain ethylene oxide units.

[0057] Component (B) contains one or more additional structural units other than ethylene oxide units. These additional structural units can be those selected from the structural units contained in a wide range of conventional rigid isocyanurate foams. Examples include structural units derived from various cyclic ethers such as alkylene oxides containing 3 or more carbon atoms and styrene oxide. The cyclic ether can be, for example, a wide range of cyclic ethers described below. For example, component (B) can be a polyether polyol compound containing ethylene oxide units and propylene oxide units. Component (B) can also be a polyether polyol compound that does not contain ethylene oxide units but contains propylene oxide units. Component (B) can also contain structural units derived from polyols described below.

[0058] The average active hydrogen number (f) of component (B) is preferably 2 or more, more preferably 3 or more, and more preferably 5 or less. An example of the active hydrogen of component (B) is a hydroxyl group.

[0059] Component (B) has a hydroxyl value of preferably less than 300 mg KOH / g, more preferably 20 to 92 mg KOH / g, and most preferably 36 to 76 mg KOH / g. The hydroxyl value of component (B) can be determined in the same manner as the hydroxyl value of component (A) described above.

[0060] The mass average molecular weight (Mw) of component (B) is not particularly limited, and, for example, it may be in the same range as that of the polyether polyol compound used for producing conventional rigid isocyanurate foams. For example, the mass average molecular weight (Mw) of component (B) is preferably 1000 or more and 10000 or less. The mass average molecular weight of component (B) may also be measured by GPC in the same manner as for component (A) described above.

[0061] Component (B) contained in the polyol composition may be of a single type, or of two or more types, i.e., may be composed of one polyether polyol or two or more different polyether polyols, in which case each polyether polyol of component (B) has an ethylene oxide unit content of 10% by mass or less based on the total amount of alkylene oxides of the corresponding polyether polyol of component (B).

[0062] Component (C) is a trifunctional or higher functional polyether polyol compound having a hydroxyl value of 300 mgKOH / g or more. Component (A) and component (B) described above are different from component (C) (in other words, component (A) and component (B) are polyether polyol compounds other than a trifunctional or higher functional polyether polyol compound having a hydroxyl value of 300 mgKOH / g or more).

[0063] Component (C) is preferably a tetrafunctional or higher-functional polyether polyol compound, and is also preferably an octafunctional or lower-functional polyether polyol compound. An example of the active hydrogen of component (C) is a hydroxyl group.

[0064] From the perspective of easily forming a rigid isocyanurate foam having excellent energy absorption performance and sound absorption performance, component (C) preferably has a hydroxyl value of 400 mg KOH / g or more. The upper limit of the hydroxyl value of component (C) is not particularly limited, and for example, it may be preferably 800 mg KOH / g or less, and more preferably 500 mg KOH / g or less. The hydroxyl value of component (C) can be measured in the same manner as the hydroxyl value of component (A) described above.

[0065] The mass average molecular weight (Mw) of the component (C) is not particularly limited, and, for example, is preferably 100 or more and 1000 or less. The mass average molecular weight of the component (C) can be measured by GPC in the same manner as that of the component (A).

[0066] Component (C) is not particularly limited in terms of structural unit type, as long as component (C) is a trifunctional or higher functional polyether polyol compound with a hydroxyl value of 300 mg KOH / g or more. For example, the structural unit contained in component (C) can be selected from those contained in a wide range of conventional rigid isocyanurate foams. Examples include structural units derived from various cyclic ethers such as alkylene oxides containing 3 or more carbon atoms and styrene oxide. The cyclic ether can be, for example, a wide range of cyclic ethers described below, and a specific example is a propylene oxide unit. Component (C) may also contain structural units derived from polyols described below.

[0067] Component (C) contained in the polyol composition may be of a single type, or of two or more types, i.e., may be composed of one polyether polyol or two or more different polyether polyols, in which case each polyether polyol of component (C) is a trifunctional or higher-functional polyether polyol compound having a hydroxyl value of 300 mg KOH / g or more.

[0068] The method for producing component (A), component (B) and component (C) is not particularly limited, and these components can be produced, for example, according to known methods. Specifically, these components can be produced by addition polymerization of cyclic ethers, condensation of polyols, or addition polymerization between cyclic ethers and polyols. The types of cyclic ethers and polyols as starting materials are not particularly limited, and can be appropriately selected according to the structure of the polyether polyol compound (target product). In particular, when producing component (A), starting materials can be selected so that the ethylene oxide (oxyethylene) unit content in component (A) is more than 50% by mass. When producing component (B), starting materials can be selected so that the ethylene oxide unit content in component (B) is less than 10% by mass.

[0069] Examples of the cyclic ethers include styrene oxide, propylene oxide, tetrahydrofuran, butylene oxide, and epichlorohydrin, in addition to ethylene oxide. These cyclic ethers may be used alone or in combination of two or more. Examples of polyols include diol compounds such as ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, 1,2-propylene glycol, dipropylene glycol, tripropylene glycol, tetrapropylene glycol, 1,3-propylene glycol, 1,4-butylene glycol, 1,3-butylene glycol, 2,3-butylene glycol, 1,5-pentanediol, 1,6-hexanediol, 2,2-dimethyl-1,3-propylene glycol, 1,4-dihydroxycyclohexane, 1,4-dimethylolcyclohexane, 1,8-octanediol, 1,10-decanediol and 1,12-dodecanediol; and trifunctional or higher functional polyols such as trimethylolpropane, glycerol (glycerol) and pentaerythritol. These polyols can be used alone or in combination of two or more. The polyol for producing component (C) is preferably pentaerythritol.

[0070] Component (A), component (B) and component (C) may be, for example, commercial products.

[0071] The polyol composition may contain other components as long as the polyol composition contains component (A), component (B) and component (C). For example, the polyol composition may contain one or more additional polyether polyol compounds in addition to component (A), component (B) and component (C), or may contain other polyol compounds such as polyester polyol, polycarbonate polyol, polyester ether polyol, polyester polycarbonate polyol, polylactone polyol, polybutadiene polyol, polymer polyol or silicone polyol, as long as the effects of the present invention are not impaired.

[0072] The polyol compound contained in the polyol composition may be only a polyether polyol compound, and may be composed of component (A), component (B), and component (C).

[0073] In addition to component (A), component (B) and component (C), the polyol composition may contain various additives for producing rigid isocyanurate foam. It should be noted that the polyol composition does not contain polyisocyanurate described below.

[0074] Examples of additives that may be included in the polyol composition include blowing agents, catalysts, crosslinking agents, foam stabilizers, and emulsifiers.

[0075] The blowing agent can be of any type and can be selected, for example, from a wide range of known blowing agents for producing conventional rigid isocyanurate foams. Examples of blowing agents include chemical blowing agents such as water and carboxylic acid compounds; and physical blowing agents such as halogenated hydrocarbon compounds, including hydrofluoroolefins and hydrochlorofluoroolefins. The blowing agent contained in the polyol composition is preferably water. The blowing agent contained in the polyol composition can be a single type, or two or more types.

[0076] The content of the blowing agent is not particularly limited, and for example, its content may be comparable to that in known rigid isocyanurate foams. The content of the blowing agent is preferably 1 to 20% by mass based on the total mass of the polyol composition and polyisocyanate described below.

[0077] The catalyst can be of any type and can be selected, for example, from a wide range of known catalysts for producing conventional rigid isocyanurate foams. Preferably, the catalyst is, for example, a catalyst that promotes the reaction between water and isocyanate (foaming catalyst), a catalyst that promotes the reaction between polyol and isocyanate (resinizing catalyst), or a catalyst that promotes the trimerization of isocyanate (i.e., forming isocyanurate rings) (trimerization catalyst). The catalyst contained in the polyol composition can be a single type, or two or more types.

[0078] Examples of the blowing catalyst include dimorpholine-2,2-diethyl ether, N,N,N',N",N"-pentamethyldiethylenetriamine, bis(dimethylaminoethyl)ether, 2-(2-dimethylaminoethoxy)ethanol, and N,N,N'-trimethyl-N'-hydroxyethylbisaminoethyl ether.

[0079] Examples of the resinification catalyst include amine catalysts such as triethylenediamine, N,N-dimethylcyclohexylamine, N,N,N",N'-tetramethylethylenediamine, N,N,N',N",N'",N''-hexamethyltriethylenetetramine, N-dimethylaminoethyl-N'-methylpiperazine, N,N,N',N'-tetramethylhexamethylenediamine, 1,2-dimethylimidazole, 1-isobutyl-2-methylimidazole, N,N-dimethylaminopropylamine and bis(dimethyl)imide. The amine catalyst and alkanolamine catalyst used herein may be an amine carbonate synthesized by adding carbonic acid, or an amine carboxylate synthesized by adding carboxylic acid (such as formic acid or acetic acid).

[0080] Examples of trimerization catalysts include aromatic compounds such as 2,4,6-tris(dialkylaminoalkyl)hexahydro-S-triazine, 1,3,5-tris(N,N-dimethylaminopropyl)hexahydro-S-triazine, 2,4,6-tris(dimethylaminomethyl)phenol and 2,4-bis(dimethylaminomethyl)phenol; alkali metal salts of carboxylic acids such as potassium acetate, potassium 2-ethylhexanoate and potassium octoate; and quaternary ammonium salts of carboxylic acids and onium salts of carboxylic acids.

[0081] The catalyst content in the polyol composition is not particularly limited, and for example, its catalyst content may be comparable to that in known rigid isocyanurate foams. The catalyst content is preferably 0.1 to 1 mass % based on the total mass of the polyol composition and polyisocyanate described below.

[0082] The crosslinking agent may be of any type and may, for example, be selected from a wide range of known crosslinking agents for producing conventional rigid isocyanurate foams. Examples of crosslinking agents include polyols such as 1,4-butanediol, ethylene glycol, diethylene glycol and glycerol; and amines such as ethanolamine and polyethylenepolyamine. The crosslinking agent contained in the polyol composition may be of a single type, or of two or more types.

[0083] The content of the crosslinking agent is not particularly limited, and for example, its content may be comparable to that in known rigid isocyanurate foams. The content of the crosslinking agent is preferably 0.5 to 5% by mass based on the total mass of the polyol composition and polyisocyanate described below.

[0084] The foam stabilizer may be of any type and may be selected, for example, from a wide range of known foam stabilizers. Examples of foam stabilizers include silicone-type foam stabilizers and fluorochemical-type foam stabilizers, of which silicone-type foam stabilizers are preferred. The foam stabilizer may be a single type or a composition formed by combining two or more stabilizers.

[0085] The silicone type foam stabilizer can be, for example, a silicone foam stabilizer containing a polyalkylene oxide-dimethylpolysiloxane copolymer as a main component. The silicone type foam stabilizer can be only a polyalkylene oxide-dimethylpolysiloxane copolymer, or such a copolymer in combination with other components. Examples of other components that can be combined include polyalkylmethylsiloxane, glycol and polyalkylene oxide compounds. In another preferred embodiment, the foam stabilizer can be a composition containing two or more members of the following: polyalkylene oxide-dimethylpolysiloxane copolymer, polyalkylmethylsiloxane and polyalkylene oxide compound. From the perspective of foam stability, this foam stabilizer is advantageous.

[0086] Examples of commercial products of foam stabilizers include the following produced by Momentive: L-580, L-590, L-620, L-680, L-682, L-690, SC-154, SC-155, SC-240, L-598, L-2100, L-2171, SH-210, L-2114, SE-232, L-533, L-534, L-539, M-6682B, L-626, L-627, L- 3001, L-3111, L-3415, L-3002, L-3010, L-3222, L-3416, L-3003, L-3333, L-3417, L-2171, L-3620, L-3630, L-3640, L-3170, L-3360, L-3350, L-3555, L-3167, L-3150 / L-3151, L-5309, SH-209 and L-3184 (trade names). Examples of other commercial products include the following products produced by Dow Corning Toray Co., Ltd.: SF-2964, SF-2962, SF-2969, SF-2971, SF-2902L, SF-2904, SF-2908, SF-2909, SRX-274C, SZ-1328, SZ-1329, SZ-1330, SZ-1336, SZ-1346, SZ-3601, SRX-294A, SRX-280A, SRX-294A, SRX-298, SH-190, SH-192 and SH-194 (trade names).

[0087] The content of the foam stabilizer is not particularly limited, and for example, its content may be comparable to that in known rigid isocyanurate foams. The content of the foam stabilizer is preferably 0.5 to 5% by mass based on the total mass of the polyol composition and polyisocyanate described below.

[0088] Emulsifier can be any type, and can be anionic surfactant, cationic surfactant or amphoteric surfactant.Wherein, nonionic surfactant is preferred.Nonionic surfactant can not dissociate into ions in aqueous solution, and for example, can be the surfactant with hydrophilic atomic group (such as hydroxyl (-OH), ether bond (-O-), ester group (-COOR) or carbamoyl (-CONH2)) and long-chain lipophilic atomic group (such as aryl replaced by alkyl or alkyl) in molecule.Concrete nonionic surfactant comprises nonionic surfactant based on ethylene oxide, polyoxyalkyl ether, polyoxyalkyl aryl ether, polyoxyalkyl alkyl ether, polyoxyalkyl amine, fatty acid ester type nonionic surfactant, polyoxyalkylene fatty acid ester, polyethylene glycol dioleate, polyethylene oxide fatty acid diester, polyglycerol fatty acid ester, polysorbate fatty acid ester and polyethyleneimine.

[0089] The content of the emulsifier is not particularly limited, and for example, the content of the emulsifier may be comparable to that in known hard isocyanurate foams. The content of the foam stabilizer is preferably 0.5 to 10% by mass based on the total mass of the polyol composition and polyisocyanate described below.

[0090] In addition to the above-mentioned blowing agent, catalyst, crosslinking agent, foam stabilizer and emulsifier, the polyol composition can also contain various other components. Examples include additives such as anti-settling agents, defoamers, antioxidants, UV absorbers, light stabilizers, plasticizers, flame retardants, waterproofing agents, biocides, antifungal agents, pigments and dyes. These additives used can be selected from a wide range of additives for the production of conventional rigid isocyanurate foams, and each additive can be used alone, or in combination of two or more.

[0091] Polyisocyanate

[0092] The starting material composition of the present invention contains polyisocyanate as an essential component. Polyisocyanate is a compound having two or more isocyanate groups.

[0093] The polyisocyanate may be of any type and may be selected from a wide range of, for example, aliphatic, cycloaliphatic, aromatic or aromatic-aliphatic polyisocyanates.

[0094] Examples of aromatic polyisocyanates include phenylene diisocyanate, toluene diisocyanate, xylene diisocyanate, diphenylmethane diisocyanate, dimethyl diphenylmethane diisocyanate, triphenylmethane triisocyanate, naphthalene diisocyanate and polymethylene polyphenyl polyisocyanate. Examples of alicyclic polyisocyanates include cyclohexane diisocyanate, methylcyclohexane diisocyanate, isophorone diisocyanate, dicyclohexylmethane diisocyanate and dimethyl dicyclohexylmethane diisocyanate. Examples of aliphatic polyisocyanates include methylene diisocyanate, ethylene diisocyanate, propylene diisocyanate, tetramethylene diisocyanate and hexamethylene diisocyanate.

[0095] Polyisocyanates can be polyisocyanate modified products. Examples include polyisocyanates with structures such as uretdione, isocyanurate, carbamate, urea, allophanate, biuret, carbodiimide, iminooxadiazinedione, oxadiazinetrione or oxazolidinone. Used polyisocyanates can be prepolymers containing isocyanate groups obtained by reacting polyols with polyisocyanates.

[0096] The polyisocyanate contained in the starting material composition may be of a single type, or of two or more types, that is, may be composed of one polyisocyanate or two or more different polyisocyanates.

[0097] Starting material composition

[0098] As described above, the starting material composition of the present invention contains a polyol composition and a polyisocyanate.

[0099] The isocyanate index of the starting material composition of the present invention is 105 or more and 400 or less. The starting material composition provided with an isocyanate index within this range makes it easier to produce a rigid isocyanurate foam having excellent energy absorption performance and sound absorption performance.

[0100] The isocyanate index refers to a value obtained by multiplying the ratio of the isocyanate groups in the polyisocyanate component to the sum of the active hydrogen atoms reactive with the isocyanate groups in the polyol composition by 100. The active hydrogen atoms reactive with the isocyanate groups in the polyol composition are derived from, for example, the polyol component. If the blowing agent is, for example, a carboxylic acid or water, these blowing agents also have active hydrogen reactive with the isocyanate groups.

[0101] From the viewpoint of easy production of a rigid isocyanurate foam excellent in both energy absorption performance and sound absorption performance, the isocyanate index is preferably 120 or more, more preferably 130 or more, still more preferably 140 or more, and particularly preferably 180 or more; and is also preferably 300 or less, more preferably 220 or less, still more preferably 200 or less, and particularly preferably 190 or less.

[0102] The starting material composition can contain other components, as long as the starting material composition contains a polyol composition and polyisocyanates. The starting material composition can also be composed of a polyol composition and polyisocyanates. In the present invention, since the components except the polyisocyanates are all regarded as constituting the polyol composition, the starting material composition of the present invention is preferably composed of a polyol composition and polyisocyanates.

[0103] As described above, in the starting material composition of the present invention, the content of component (A) and the content of component (C) are determined as follows. Specifically, the content of component (A) is 30 parts by mass or more and 50 parts by mass or less, and the content of component (C) is 5 parts by mass or more and 35 parts by mass or less, each based on 100 parts by mass of the total amount of the starting material composition other than polyisocyanate. A content of component (A) of less than 30 parts by mass in the starting material composition may result in a decrease in the air permeability of the rigid isocyanurate foam, resulting in the inability to achieve the desired sound absorption coefficient. A content of component (A) exceeding 50 parts by mass may make it difficult to adjust the reactivity during the production of the rigid isocyanurate foam, resulting in the inability to achieve the desired shock absorption performance. A content of component (C) of less than 5 parts by mass in the starting material composition may result in the inability to form a rigid isocyanurate foam. A content of component (C) of more than 35 parts by mass in the starting material composition may result in a decrease in the air permeability of the rigid isocyanurate foam, resulting in the inability to achieve the desired sound absorption coefficient.

[0104] In the starting material composition, the phrase "the total amount of the starting material composition other than polyisocyanate" refers to, for example, the total amount of all components contained in the starting material composition other than polyisocyanate. Therefore, if the starting material composition consists of a polyol composition and a polyisocyanate, "the total amount of the starting material composition other than polyisocyanate" is synonymous with the total amount of the polyol composition. In the context of the present application, unless otherwise specified, the mass content of each component in the polyol composition should be understood as based on 100 parts by mass of the total amount of the starting material composition other than polyisocyanate.

[0105] The content of component (A) is preferably 32 parts by mass or more, preferably 48 parts by mass or less, more preferably 46 parts by mass or less, still more preferably 45 parts by mass or less, and particularly preferably 40 parts by mass or less, based on 100 parts by mass of the total amount of the starting material composition excluding the polyisocyanate.

[0106] The content of component (C) is preferably 10 parts by mass or more, more preferably 13 parts by mass or more, still more preferably 15 parts by mass or more, and particularly preferably 20 parts by mass or more, based on 100 parts by mass of the total amount of the starting material composition excluding the polyisocyanate.

[0107] The content of component (C) is also preferably 34 parts by mass or less, more preferably 32 parts by mass or less, and still more preferably 30 parts by mass or less, based on 100 parts by mass of the total amount of the starting material composition excluding the polyisocyanate.

[0108] The content of component (B) in the starting material composition is not particularly limited. From the perspective of facilitating the preparation of a rigid isocyanurate foam having excellent energy absorption and sound absorption properties, the content of component (B) is preferably 10 parts by mass or more and 15 parts by mass or less, based on 100 parts by mass of the total amount of the starting material composition excluding the polyisocyanate.

[0109] The method for preparing the starting material composition is not particularly limited. For example, the starting material composition can be prepared by mixing a polyol composition and a polyisocyanate in a predetermined ratio. The method for preparing the polyol composition is also not particularly limited. For example, the polyol composition can be obtained by mixing component (A), component (B) and component (C) and optional additives in a predetermined ratio. For example, the polyol composition and the polyisocyanate are preferably mixed at a constant liquid temperature. In this case, the liquid temperature is preferably, for example, 25 to 35° C. This makes it likely that the viscosity and fluidity of the composition fall within an appropriate range, thereby making the filling property of the composition better. This results in a reduction in the voids in the rigid isocyanurate foam. When preparing the polyol composition, components other than the blowing agent can be added in advance and then mixed with the blowing agent.

[0110] 2. Rigid isocyanurate foam

[0111] The starting material composition of the present invention can be used as a starting material for producing a rigid isocyanurate foam. Specifically, the rigid isocyanurate foam can be produced by using the starting material composition. Therefore, the rigid isocyanurate foam is a molded foam product of the starting material composition.

[0112] The method for obtaining the rigid isocyanurate foam by using the starting material composition is not particularly limited. For example, the present invention can use a wide range of known methods for producing rigid isocyanurate foams. Therefore, the rigid isocyanurate foam can be produced by foaming the starting material composition by an appropriate method and optionally molding it.

[0113] The method of foaming the starting material composition is not particularly limited, and the method used may be a known foaming technique, such as manual mixing foaming, simple foaming, continuous foaming, injection foaming, foaming injection foaming or spray foaming. The method of molding the rigid isocyanurate foam is also not particularly limited, and the method used may be a known molding technique, such as mold molding, flat plate molding, lamination molding or in-situ foam molding.

[0114] When molding the rigid isocyanurate foam, the surface temperature of the mold is preferably 50 to 70° C. This makes the reactivity moderate and allows the starting material composition to be better filled into the mold. The demolding time (the time from the start of injection of the composition for foam production to the start of opening the mold for the molded product) is preferably 120 to 600 seconds, and more preferably 180 to 360 seconds. Open molding allows the rigid isocyanurate foam to be molded in a short time, thereby easily improving production efficiency.

[0115] As described above, the rigid isocyanurate foam is obtained by using the starting material composition of the present invention; that is, the rigid isocyanurate foam is a foam of the starting material composition of the present invention.

[0116] The shape and size of the rigid isocyanurate foam are not particularly limited and may be appropriately determined depending on the intended use.

[0117] The rigid isocyanurate foam may have any density. The density of the rigid isocyanurate foam is preferably, for example, 20 to 200 kg / m 3 , and more preferably 40 to 140 kg / m 3 The density of the rigid isocyanurate foam can be measured according to JIS K7222:1999.

[0118] The air permeability of the rigid isocyanurate foam is, for example, 1 to 80 L / min, and preferably 2 to 60 L / min. This makes it easier to impart excellent sound absorbing properties to the rigid isocyanurate foam. The air permeability of the rigid isocyanurate foam can be measured according to JIS K6400-7A (negative pressure method).

[0119] Since the rigid isocyanurate foam is formed from the starting material composition of the present invention, the rigid isocyanurate foam is excellent in both energy absorption and sound absorption properties.

[0120] Since there is a trade-off between energy absorption performance and sound absorption performance, it is difficult to achieve both at the same time. However, since rigid isocyanurate foam is formed from a starting material containing specific components, a polyol composition and a polyisocyanate, rigid isocyanurate foam is excellent in both properties.

[0121] Therefore, the rigid isocyanurate foam formed from the starting material composition of the present invention is widely used in applications requiring energy absorption performance and sound absorption performance. For example, the rigid isocyanurate foam can be used in various fields such as vehicles, ships, factories, insulation equipment, construction, civil engineering, furniture and interior decoration; in particular, due to its excellent energy absorption performance and sound absorption performance, the rigid isocyanurate foam is suitable for automotive interior parts.

[0122] The rigid isocyanurate foam of the present invention can also be widely used in fields requiring energy absorption performance or sound absorption performance; for example, due to its excellent shock absorption performance, the rigid isocyanurate foam can be suitable for various safety components.

[0123] 3. Sound-absorbing materials

[0124] Rigid polyurethane foam can be used as a sound absorbing material due to its excellent sound absorbing performance. There is no particular limitation on such a sound absorbing material as long as the sound absorbing material contains a rigid isocyanurate foam. For example, the sound absorbing material can be constructed in the same manner as a known sound absorbing material. The sound absorbing material can be formed by combining the rigid isocyanurate foam with other components, or can be formed only of the rigid isocyanurate foam.

[0125] The sound absorbing material of the present invention is excellent in both energy absorbing performance and sound absorbing performance because the sound absorbing material contains the rigid isocyanurate foam obtained from the above starting material composition. Therefore, the sound absorbing material of the present invention can be suitably used for automobile interior parts.

[0126] In another embodiment of the sound absorbing material of the present invention, the sound absorbing material can be obtained by using a composition for a sound absorbing material containing a polyol composition containing component (A), component (B) and component (C) and a polyisocyanate. Specifically, a rigid isocyanurate foam formed by foaming and molding the composition for a sound absorbing material can be used as a sound absorbing material. The sound absorbing material in this embodiment is also excellent in both energy absorbing performance and sound absorbing performance. Example

[0127] The present invention will be described in more detail below with reference to Examples. However, the present invention is not limited to the embodiments of these Examples.

[0128] To prepare the rigid isocyanurate foams in Examples and Comparative Examples, the starting materials were appropriately selected from the starting materials (polyol composition and polyisocyanate) shown below.

[0129] Polyol composition

[0130] The polyol composition is prepared by selecting the following materials of component (A), component (B), component (C), a crosslinking agent, a catalyst, a foam stabilizer, a blowing agent and an emulsifier.

[0131] Component (A)

[0132] Glycerin was addition polymerized with propylene oxide and ethylene oxide to obtain a polyether polyol (A) having an average active hydrogen number (f) of 3.0, a hydroxyl value of 37 mg KOH / g, a mass average molecular weight of about 4500, and an ethylene oxide unit content of 70% by mass.

[0133] Component (B)

[0134] Glycerin and propylene oxide were subjected to addition polymerization to obtain a polyether polyol (B) having an average active hydrogen number (f) of 3.0, a hydroxyl value of 56 mgKOH / g, and a mass average molecular weight of about 3,000.

[0135] Component (C)

[0136] Pentaerythritol and propylene oxide were subjected to addition polymerization to obtain a polyether polyol (C) having an average active hydrogen number (f) of 4.0, a hydroxyl value of 410 mg KOH / g, and a mass average molecular weight of about 487.

[0137] Crosslinking agent

[0138] Cross-linking agent 1: Glycerol (manufactured by Kao Corporation)

[0139] catalyst

[0140] Catalyst: DABCO BL-11 (produced by Evonik Industries AG)

[0141] Catalyst: DABCO EG (produced by Evonik Industries AG)

[0142] Catalyst 3: DABCO K-15 (produced by Evonik Industries AG)

[0143] Catalyst 4: Potassium acetate

[0144] Foaming agent

[0145] ·water

[0146] Foam stabilizer

[0147] SRX-280A (manufactured by Dow Corning Toray Co., Ltd.)

[0148] Emulsifier

[0149] Emulsifier 1: EMALEX DEG-di-O (manufactured by Nihon Emulsion Co., Ltd.)

[0150] Emulsifier 2: IONET DO-600 (manufactured by Sanyo Chemical Industries, Ltd.)

[0151] Polyisocyanate

[0152] Polymethylene polyphenyl polyisocyanate (isocyanate group content: 31.5 mass%)

[0153] Example 1

[0154] According to the formula of Table 1, a starting material composition containing a polyol composition and a polyisocyanate was first prepared according to the following steps. First, 40 parts by mass of component (A), 12 parts by mass of component (B) and 5 parts by mass of component (C), as well as additives (crosslinking agent, catalyst, foam stabilizer and emulsifier) ​​were mixed in a mixing tank according to the formula shown in Table 1. Then, a blowing agent was added to the mixture obtained in the formula shown in Table 1 to prepare a polyol composition. While the polyol composition was maintained at 30°C, polyisocyanate was added thereto in such an amount that the isocyanate index shown in Table 1 was reached, and then mixed under stirring. The mixture in liquid form was injected into a mold, foamed and cured. A high-pressure foam-molding machine was used to foam the polyol composition by injecting it into a mold. In this step, the composition of the present invention was prepared as a single composition by mixing the polyol mixture with the polyisocyanate and then injecting it into the mold. The high-pressure foam-molding machine used was Model A System 40 produced by Canon Inc. For mold molding, open injection was performed at a discharge rate of 200 to 250 g / sec, a mixing pressure of 15 MPa, and an injection time of 0.5 to 0.8 sec to obtain a molded product (200 mm×200 mm×50 mm). During the mold molding, the surface temperature was maintained at 60° C. or about 60° C. The desired hard isocyanurate foam was obtained through the above operation.

[0155] Examples 2 to 13

[0156] A rigid isocyanurate foam was obtained in the same manner as in Example 1, except that the types and amounts of the starting materials were changed as shown in Table 1.

[0157] Comparative Examples 1 to 4

[0158] A rigid isocyanurate foam was obtained in the same manner as in Example 1, except that the types and amounts of the starting materials were changed as shown in Table 1.

[0159] Evaluation Method

[0160] The density, air permeability, sound absorption coefficient, presence or absence of free foam, compressive strength and compressive stress of the rigid isocyanurate foam (specimen) obtained in each of the examples and comparative examples were measured.

[0161] Sound absorption coefficient

[0162] The sound absorption coefficient of the rigid isocyanurate foam was measured according to JIS A1405-2. A sound absorption coefficient of 10% or more at 2000 Hz was judged as acceptable (preferably 15% or more), and a sound absorption coefficient of 20% or more at 3150 Hz was judged as acceptable.

[0163] Free foam formation and appearance

[0164] In addition, according to the formula shown in Table 1, the starting material composition prepared in the same manner as the embodiment and the comparative example was added to a 2L cup, foamed and cured. The high-pressure foaming molding machine was used to foam each polyol composition by injecting it into a mold. In this step, the composition of the present invention is prepared as a single composition by mixing a polyol mixture with a polyisocyanate and then injecting it into a mold. The high-pressure foaming molding machine used is the Model A System 40 produced by Canon Inc. For mold molding, open injection was performed at a discharge of 250 g / sec, a mixing pressure of 15 MPa, and an injection time of 0.4 seconds to obtain a sample for free foam evaluation. The appearance of the obtained sample (the bulge and collapse of the foam, whether shrinkage occurs) was visually observed and evaluated according to the following criteria.

[0165] A: Excellent foam rise, no collapse, and no shrinkage or deformation.

[0166] B: Collapse occurs, and the foam does not swell, shrink, or deform.

[0167] Compressive strength, compressive stress and energy absorption performance

[0168] Cut the rigid isocyanurate foam into blocks of 50mm×50mm×50mm as measurement samples. The measuring equipment used is a precision universal testing machine (produced by MinebeaMitsumi Inc.). Place the measurement sample flat on the center of the testing machine workbench, and then place a pressure plate on the top surface of the sample. When the load reaches 1N (initial thickness measurement load), read the thickness of the sample to the nearest 0.1mm unit, and determine the thickness as the initial thickness. Subsequently, press the pressure plate into the measurement sample at a speed of 10mm / min until the thickness reaches 80% of the initial thickness, and the load at this time is determined as the compressive strength (N) of the rigid isocyanurate foam. Calculate the compressive stress according to the following formula.

[0169] Compressive stress (N / m 2 ) = compression load (N) / area of ​​compression surface (m 2 )

[0170] The energy absorption performance was evaluated based on the value of the increase in compressive stress expressed by the following formula.

[0171] Compressive stress increase (%) =

[0172] [(maximum stress when the sample is compressed by 50%) - (maximum stress when the sample is compressed by 10%)] / (maximum stress when the sample is compressed by 10%) × 100

[0173] A compressive stress increase of 40% or less was judged as acceptable (the sample had excellent energy absorption performance).

[0174] density

[0175] The density of the rigid isocyanurate foam was measured in accordance with JIS K 7222:1999.

[0176] Breathability

[0177] The air permeability of the rigid isocyanurate foam was measured according to JIS K6400-7A (negative pressure method). An air permeability of 0.5 L / min or more was judged to be acceptable. In this measurement, a core portion (50 mm×50 mm×25 mm) of the rigid isocyanurate foam was used as a measurement sample.

[0178] Table 1

[0179]

[0180] As shown in Table 1, the rigid isocyanurate foams obtained in Examples were rated as good in terms of free foam formation and appearance, and were rated as excellent in terms of foam moldability, appearance, and air permeability. In Comparative Example 1, physical properties could not be measured due to defective free foam formation. The air permeability of the rigid isocyanurate foams obtained in Comparative Examples 2 and 5 was "0", which clearly indicated the lack of the desired sound absorption performance.

[0181] Each of the rigid isocyanurate foams obtained in the examples also had a sound absorption coefficient of more than 10% at 2000 Hz, indicating excellent sound absorption performance. The rigid isocyanurate foams obtained in the examples had a small increase in compression stress (less than 40%) when compressed by 10% to 50%, and showed a high retention rate, indicating excellent energy absorption performance. Therefore, it was found that the rigid isocyanurate foams obtained by starting materials containing a specific polyol composition and a specific polyisocyanate were excellent in both sound absorption performance and energy absorption performance.

Claims

1. A starting material composition for a rigid isocyanurate foam, the starting material composition comprising a polyol composition and a polyisocyanate, The polyol composition comprises a trifunctional or higher-functional polyether polyol (C) having a hydroxyl value of 300 mg KOH / g or more, a polyether polyol (A) different from the polyol (C) having an ethylene oxide content of 50% by mass or more based on the total amount of alkylene oxides of the polyether polyol (A), and a polyether polyol (B) different from the polyol (C) having an ethylene oxide content of 10% by mass or less based on the total amount of alkylene oxides of the polyether polyol (B), in The content of component (A) is 30 parts by mass or more and 50 parts by mass or less, and the content of component (C) is 5 parts by mass or more and 35 parts by mass or less, each based on 100 parts by mass of the total amount of the starting material composition excluding the polyisocyanate, and The isocyanate index of the starting material composition is 105 or more and 400 or less. 2 . The starting material composition according to claim 1 , wherein the content of component (B) is 10 parts by mass or more and 15 parts by mass or less based on 100 parts by mass of the total amount of the starting material composition excluding the polyisocyanate.

3. A method for producing a rigid isocyanurate foam, comprising the step of reacting the starting material composition according to claim 1 or 2.

4. A rigid isocyanurate foam obtained by reacting a starting material composition according to claim 1 or 2.

5. A sound absorbing material comprising the rigid isocyanurate foam according to claim 4.

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