JP2016194034A - Production method of urethane foam - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a production method of an urethane foam excellent in moldability and gas barrier property.SOLUTION: A production method of an urethane foam includes a step of expanding a volume of a mixture containing a filler (e) selected from silica, montmorillonite and mixture thereof, and compressed fluid, or a mixture (X) containing the filler (e), polyol (a) and the compressed fluid, and acquiring filler particles (e1) whose volume average particle diameter is 10-1,000 nm. The compressed fluid is a fluid formed by compressing carbon dioxide, a subcritical fluid or a supercritical fluid, and the filler particles (e1) are dispersed in the urethane foam.SELECTED DRAWING: None

Description

  The present invention relates to a method for producing urethane foam. More specifically, the present invention relates to a method for producing a urethane foam suitable for applications requiring excellent gas barrier properties, and a method for producing a filler particle-dispersed polyol composition that can be used in this production method.

  Conventionally, urethane foam has been widely used as automobile interior materials and building materials. In recent years, fillers such as silica and montmorillonite have been used as auxiliary agents for urethane to improve the gas barrier properties of urethane foam (see Non-Patent Document 1). However, with the conventional dispersibility and the dispersed particle size of the filler, there is a problem that the effect of gas barrier properties is small when used in a small amount, and the moldability of the foam deteriorates and the strength decreases when used in a large amount.

Polyurethane application technology (published by CMC)

  An object of this invention is to obtain the manufacturing method of the urethane foam excellent in the moldability and gas barrier property.

  As a result of intensive studies to solve such problems, the present inventors made a urethane foam containing a filler whose particle size was adjusted by volume expansion of a mixed liquid containing a filler and a compressed fluid. The present inventors have found that the above problems can be solved and have reached the present invention.

The above-mentioned subject is achieved by the following present invention.
That is, the present invention is the following two inventions.
(I) Volume expansion of a mixed solution containing a filler (e) selected from silica, montmorillonite and a mixture thereof and a compressed fluid, or a mixed solution (X) containing a filler (e), a polyol (a) and a compressed fluid Including a step of obtaining filler particles (e1) having a volume average particle diameter of 10 to 1000 nm, wherein the compressed fluid contains a liquid, a subcritical fluid or a supercritical fluid obtained by compressing carbon dioxide. A method for producing a urethane foam in which particles (e1) are dispersed.
(II) Volume expansion of the mixture (X1) containing the filler (e) selected from silica, montmorillonite and a mixture thereof, the polyol (a) and the compressed fluid, so that the volume average particle diameter is 10 in the polyol (a). A method for producing a filler particle-dispersed polyol composition to obtain a polyol composition in which filler particles (e1) of ˜1000 nm are dispersed.

  Since the urethane foam obtained by the production method of the present invention is excellent in moldability and gas barrier properties, it can be widely used as a rigid foam for building materials.

In the method for producing a urethane foam of the present invention, the polyol (a) and the organic polyisocyanate (b) are reacted in the presence of the filler particles (e1), the foaming agent (c), and the urethanization catalyst (d). preferable.
As said polyol (a), what can be normally used for manufacture of urethane is used, For example, a polyhydric alcohol, polyalkanolamine, polyether polyol, polyester polyol, various other polyols, etc. are mentioned, 2 or more types May be used in combination.

  Examples of polyhydric alcohols include dihydric alcohols having 2 to 20 carbon atoms (aliphatic diols such as ethylene glycol, propylene glycol, 1,3- and 1,4-butanediol, 1,6-hexanediol, neopentyl glycol. And alicyclic diols such as cyclohexane diol and cycloalkylene glycol such as cyclohexane dimethanol, trihydric alcohols having 3 to 20 carbon atoms (aliphatic triols such as glycerin, trimethylol propane and trimethylol) Alkanetriols such as ethane and hexanetriol); 4 to 8 or more polyhydric alcohols having 5 to 20 carbon atoms (aliphatic polyols such as pentaerythritol, sorbitol, mannitol, sorbitan, diglyceride) Emissions, alkane polyols and their intramolecular or intermolecular dehydration products, such as dipentaerythritol; and sucrose, glucose, mannose, fructose, sugars and their derivatives such as methyl glucoside) and the like.

  Examples of the polyalkanolamine include polyalkanolamines having 2 to 20 carbon atoms (mono-, di- and triethanolamine, isopropanolamine, etc.).

  Examples of the polyether polyol include polyols having a structure in which an alkylene oxide is added to an active hydrogen-containing compound such as the polyhydric alcohol, ammonia, amine, polyhydric phenol, and polycarboxylic acid, and mixtures thereof.

  Examples of amines include aliphatic amines [monoamines (C (C) 1-20, such as n-butylamine, octylamine), diamines (C2-10, such as ethylenediamine, propylenediamine, hexamethylenediamine), polyalkylenepolyamines (C4). -20, such as diethylenetriamine, triethylenetetramine, pentaethylenehexamine, etc.]; aromatic (aliphatic) amines (C6-20 mono- and polyamines such as aniline, phenylenediamine, tolylenediamine, xylylenediamine, diethyltoluylene diamine) Amines, methylene dianilines, diphenyl ether diamines); alicyclic amines (C4-20, such as isophorone diamine, cyclohexane diamine, dicyclohexyl methane diamine); heterocyclic amines (C4-20). For example piperazine, those aminoethylpiperazine and Sho 55-21044 JP); alkanolamines (C2-20, such as mono-, - di - and triethanolamine, isopropanol amine and the like) and the like.

  Polyhydric (divalent to octavalent or higher) phenols include monocyclic polyhydric phenols (hydroquinone, resorcinol, pyrogallol, phloroglucin, etc.); polycyclic polyhydric phenols (dihydroxynaphthalene, etc.); bisphenol compounds (bisphenol A, − F and S); condensates of phenol and formaldehyde (novolak, resol, etc.) and the like.

  Examples of the polycarboxylic acid include aliphatic polycarboxylic acids (C4-18, such as succinic acid, adipic acid, sebacic acid, glutaric acid, azelaic acid), aromatic polycarboxylic acids (C8-18, such as terephthalic acid, isophthalic acid, Orthophthalic acid, trimellitic acid, pyromellitic acid), alicyclic polycarboxylic acid (C8-15, such as cyclohexane 1,4-dicarboxylic acid), and a mixture of two or more of these.

The alkylene oxide added to the active hydrogen-containing compound (which may be used in combination of two or more) is C2-12 or more (preferably 2-8), such as ethylene oxide, 1,2-propylene oxide, 1, 2-, 2,3- and 1,3-butylene oxide (hereinafter abbreviated as EO, PO and BO, respectively), tetrahydrofuran and 3-methyl-tetrahydrofuran, 1,3-propylene oxide, isoBO, C5-12 α- Olefin oxides, substituted alkylene oxides such as styrene oxide and epihalohydrins (such as epichlorohydrin), and combinations of two or more thereof (random addition and / or block addition) are included.
Of these, PO and a combination of EO / PO are more preferable from an industrial viewpoint.
The addition amount of alkylene oxide is preferably 1 to 10 mol, more preferably 2 to 6 mol, per active hydrogen atom.

  Examples of the polyester polyol include the above-mentioned polyols (particularly, dihydric alcohols such as ethylene glycol, diethylene glycol, propylene glycol, 1,3- or 1,4-butanediol, 1,6-hexanediol, neopentyl glycol; A mixture with a trihydric or higher polyhydric alcohol such as glycerin or trimethylolpropane; and an alkylene oxide low-mole (1 to 10 mol) adduct of these polyhydric alcohols) and the polycarboxylic acid or anhydride thereof, Ester-forming derivatives such as lower alkyl (carbon number of alkyl group: 1 to 4) ester (for example, adipic acid, sebacic acid, maleic anhydride, phthalic anhydride, dimethyl terephthalate, etc.), or the carboxylic acid anhydride and Condensation with alkylene oxide Reaction product thereof; alkylonoxide (EO, PO, etc.) addition reaction product; polylactone polyol, for example, obtained by ring-opening polymerization of lactone (ε-caprolactone, etc.) using the polyol as an initiator; polycarbonate polyol, for example A reaction product of the polyhydric alcohol and alkylene carbonate; and the like. Specific examples include poly (1,4-butanediol adipate), poly (1,4-butanediol terephthalate), poly (diethylene glycol terephthalate), polyε-caprolactone polyol, and the like. The number average molecular weight (Mn) is preferably 150 to 3,000, more preferably 200 to 2,500, and particularly preferably 250 to 1,500 from the viewpoint of mechanical properties of the urethane foam.

Examples of other polyols include polymer polyols (hereinafter abbreviated as P / P) and hydroxyl group-containing vinyl polymers (polybutadiene polyol, partially saponified ethylene / vinyl acetate copolymer, etc.).
Examples thereof include polymer polyols (hereinafter abbreviated as P / P) and hydroxyl group-containing vinyl polymers (polybutadiene polyol, partially saponified ethylene / vinyl acetate copolymer, etc.).
P / P is obtained by in-situ polymerization of ethylenically unsaturated monomers in a polyol (the OH-terminated polyether polyol and / or polyester polyol, or a mixture thereof with the polyhydric alcohol).
Ethylenically unsaturated monomers include acrylic monomers [(meth) acrylonitrile, alkyl (C1-20 or higher) (meth) acrylate (methyl methacrylate, etc.)], hydrocarbon (hereinafter abbreviated as HC) monomer [aromatic unsaturated Saturated HC (styrene, etc.), aliphatic unsaturated HC (C2-20 or higher alkenes, alkadienes, etc. (α-olefins, butadiene, etc.)), and combinations of two or more of these [acrylonitrile / styrene combinations ( Weight ratio 100/0 to 80/20) and the like.
P / P has, for example, a polymer content of 5 to 80% by weight or more, preferably 30 to 70% by weight. Mn is preferably 150 to 3,000, more preferably 200 to 2,500, and particularly preferably 250 to 1,500 from the viewpoint of mechanical properties of the urethane foam.

  A preferable range of the OH equivalent of the polyol (a) is 31 to 4000. When manufacturing a rigid urethane foam, the OH equivalent of (a) is more preferably 50-200. When producing a flexible urethane foam, the OH equivalent of (a) is more preferably 500 to 4000. In the case of flexible urethane foam, (a) having an OH equivalent of preferably 31 to 80 is used in combination with 10% by weight or less (preferably 0.5 to 6% by weight) in (a) as a crosslinking agent or chain extender. May be.

  As the organic polyisocyanate (b) used in the present invention, those conventionally used for urethane foam can be used. Examples of such isocyanates include aromatic polyisocyanates, aliphatic polyisocyanates, alicyclic polyisocyanates, araliphatic polyisocyanates, and modified products thereof (for example, urethane groups, carbodiimide groups, allophanate groups, urea groups, burettes). Group, an isocyanurate group, or an oxazolidone group-containing modified product) and a mixture of two or more thereof.

  The aromatic polyisocyanate includes 6 to 16 aromatic diisocyanates, 6 to 20 aromatic triisocyanates, and crude products of these isocyanates (excluding carbon in the NCO group; the following isocyanates are also the same). Is mentioned. Specific examples include 1,3- and 1,4-phenylene diisocyanate, 2,4- and 2,6-tolylene diisocyanate (TDI), crude TDI, 2,4′- and 4,4′-diphenylmethane diisocyanate ( MDI), polymethylene polyphenyl isocyanate (crude MDI), naphthylene-1,5-diisocyanate, triphenylmethane-4,4 ′, 4 ″ -triisocyanate and the like. Examples of the aliphatic polyisocyanate include aliphatic diisocyanates having 6 to 10 carbon atoms. Specific examples include 1,6-hexamethylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, lysine diisocyanate, and the like.

  Examples of the alicyclic polyisocyanate include alicyclic diisocyanates having 6 to 16 carbon atoms. Specific examples include isophorone diisocyanate, 4,4'-dicyclohexylmethane diisocyanate, 1,4-cyclohexane diisocyanate, and norbornane diisocyanate. Examples of the araliphatic polyisocyanate include araliphatic diisocyanates having 8 to 12 carbon atoms. Specific examples include xylylene diisocyanate, α, α, α ′, α′-tetramethylxylylene diisocyanate, and the like. Specific examples of the modified polyisocyanate include urethane-modified MDI, carbodiimide-modified MDI, sucrose-modified TDI, and castor oil-modified MDI. Among these, one or more organic polyisocyanates selected from TDI, MDI, crude TDI, crude MDI, sucrose-modified TDI, urethane-modified MDI, and carbodiimide-modified MDI are preferable.

  The isocyanate index [(NCO group / active hydrogen atom-containing group equivalent ratio × 100)] in the production of urethane foam is preferably 60 to 500, more preferably 80 to 350, and particularly preferably 85 to 300.

  In the present invention, it is preferable to use water as the foaming agent (c). When only water is used alone in (c), the amount of water used is preferably 0 to 30 parts by weight, more preferably 0.2 to 20 parts by weight per 100 parts by weight of polyol (a). In addition, hydrogen atom-containing halogenated hydrocarbons, low boiling point hydrocarbons, liquefied carbon dioxide, etc. are used as necessary.

  Specific examples of the hydrogen atom-containing halogenated hydrocarbon foaming agent include those of the HCFC (hydrochlorofluorocarbon) type (for example, HCFC-123, HCFC-141b, HCFC-22, and HCFC-142b); HFC (hydrofluorocarbon) type (E.g., HFC-134a, HFC-152a, HFC-356mff, HFC-236ea, HFC-245ca, HFC-245fa and HFC-365mfc); HFO (hydrofluoroolefin) type (e.g. 1234yf). Among these, HCFC-141b, HFC-134a, HFC-356mff, HFC-236ea, HFC-245ca, HFC-245fa, HFC-365mfc and a mixture of two or more thereof are preferred. The amount of hydrogen atom-containing halogenated hydrocarbon used is preferably 50 parts by weight or less, more preferably 45 parts by weight or less per 100 parts by weight of polyol (a).

  The low boiling point hydrocarbon is usually a hydrocarbon having a boiling point of −5 to 50 ° C., and specific examples thereof include butane, pentane, cyclopentane, and mixtures thereof. The amount of low boiling point hydrocarbon used is preferably 40 parts by weight or less, more preferably 30 parts by weight or less per 100 parts by weight of (a). The amount of liquefied carbon dioxide used is preferably 30 parts by weight or less, more preferably 25 parts by weight or less per 100 parts by weight of (a).

  The urethanization catalyst (d) used in the present invention is a catalyst usually used for the urethanation reaction, such as an amine catalyst [triethylenediamine, N-ethylmorpholine, diethylethanolamine, N, N, N ′, N ′. -Tetramethylhexamethylenediamine, 1-isobutyl-2-methylimidazole, 1,8-diazabicyclo- [5,4,0] -undecene-7, bis (dimethylaminoethyl) ether (carboxylate), etc.] and / or Alternatively, a metal catalyst (stannic octylate, dibutylstannic dilaurate, lead octylate, etc.) can be used. The amount of the urethanization catalyst (d) used is preferably 0.001 to 6 parts by weight per 100 parts by weight of the polyol (a).

  Examples of the filler (e) used in the present invention include dry or wet silica, montmorillonite, and mixtures thereof.

In the method for producing the urethane foam of the present invention, a volume average is obtained by volume expansion of the mixed solution containing the filler (e) and the compressed fluid or the mixed solution (X) containing the filler (e), the polyol (a) and the compressed fluid. Filler particles (e1) having a particle size adjusted to 10 to 1000 nm are used.
In the present invention, examples of the compressed fluid include liquids obtained by compressing carbon dioxide, subcritical fluids, and supercritical fluids.

The volume average particle diameter of the filler particles (e1) is usually 10 to 1000 nm, preferably 20 to 300 nm. If the particle size exceeds 1000 nm, the dispersion stability in the polyol (a) may be deteriorated. Here, the volume average particle diameter is measured by a laser diffraction / scattering particle size distribution measuring apparatus [for example, “LA-920” manufactured by Horiba, Ltd.].
The volume average particle diameter of the filler particles (e1) does not normally change during the production of urethane foam.

  The content of the filler particles (e1) in the urethane foam obtained by the production method of the present invention is 0.1% with respect to the total weight of the polyol (a) regardless of whether the filler particles (e1) are silica or montmorillonite. It is preferable to set it as -30 weight%, and 5-30 weight% is still more preferable. When the content of the filler particles (e1) is 0.1% by weight or more, sufficient gas barrier performance can be obtained. On the other hand, if it is 30% by weight or less, there is no fear of lowering mechanical properties, and the cost is reduced.

  Other additives (f) used for the production of urethane foam include foam stabilizers (dimethylsiloxane-based, polyether-modified dimethylsiloxane-based, etc.), isocyanuration catalysts (for example, potassium octylate, quaternary ammonium salts), Flame retardant (phosphate ester, halogenated phosphate ester, aluminum hydroxide, antimony oxide, boron compound, bromine compound, chlorinated paraffin, cyclic fatty acid, etc.), colorant (dye, content, etc.), plasticizer (phthalate ester) , Adipic acid esters, etc.), organic fillers (synthetic short fibers, hollow microspheres made of thermoplastic or thermosetting resins, etc.), antioxidants (hindered phenols, hindered amines, etc.), anti-aging agents (triazoles) System, benzophenone system, etc.), mold release agent (wax system, metal soap system, or a mixture of these), etc. It can be reacted in the presence of additives known.

  An example of a method for producing a urethane foam according to the method of the present invention is as follows. First, filler particles (e1) having a volume average particle size of 10 to 1000 nm are dispersed in at least a part of the polyol (a), and then added as a blowing agent (c), a urethanization catalyst (d), and if necessary. A predetermined amount of the agent (f) and / or the remaining polyol (a) is mixed. The mixture and organic polyisocyanate (b) are then rapidly mixed using a urethane low pressure or high pressure injection foaming machine or a stirrer. The obtained mixed liquid (foaming stock solution) is poured into a sealed or open mold (made of metal or resin), subjected to urethanization reaction, cured for a predetermined time, and then demolded to obtain urethane foam. Also, urethane foam can be obtained by spray foaming or continuous foaming.

  In the step of dispersing filler particles (e1) having a volume average particle diameter of 10 to 1000 nm in at least a part of the polyol (a), examples of methods include (1) a compressed fluid of carbon dioxide and a filler ( After preparing a mixed liquid (X1) of e) and polyol (a), (X1) is volume-expanded and a dispersion of filler particles (e1) and polyol (a) from which carbon dioxide has been removed (filler particles) (2) A mixed liquid (X2) of a compressed fluid of carbon dioxide and a filler (e) is prepared, and then (X2) is sprayed and expanded in volume toward the polyol (a). And a method of obtaining a dispersion of filler particles (e1) and polyol (a) from which carbon dioxide has been removed (filler particle-dispersed polyol composition), and the like. . Among these methods, the method (1) facilitates obtaining a dispersion in which filler particles having a smaller volume average particle size are dispersed.

In the production method of the above (1) or (2), the mixed liquid (X1) of the filler (e), the polyol (a) and the compressed fluid, or the mixed liquid (X2) of (e) and the compressed fluid (( X1) or (X2) is referred to as (X). ], The filler particles (e1) having a volume average particle diameter of 10 to 1000 nm can be obtained.
In the case of the method (1) using a mixed liquid (X1) containing a filler (e), a polyol (a) and a compressed fluid, filler particles (e1 having a volume average particle diameter of 10 to 1000 nm in the polyol (a). ) Can be easily obtained (the second invention).
In the method (1), the amount of the filler (e) used relative to the polyol (a) is preferably 1 to 100% by weight with respect to the polyol (a) from the viewpoint of the volume average particle diameter of the filler particles (e1) to be obtained. 5 to 80% by weight is more preferable.

  The time required for mixing the filler (e) with the compressed fluid and, if necessary, the polyol (a) in the mixed solution (X) is the time during which the compressed fluid penetrates into the filler (e) and no pressure drop occurs over time. That is enough.

  As means for expanding the volume, there are heating operation of the compressive fluid and decompression operation, but volume expansion by the decompression operation is preferable for efficient pulverization and pulverization.

In order to efficiently pulverize and disintegrate the liquid mixture (X) by volume expansion, it is preferable to reduce the pressure to the target pressure at once. Therefore, when the compressed fluid is removed from the pressure vessel in which the mixed liquid (X) is prepared to obtain a filler having a small particle size, a pressure reducing valve capable of reducing the pressure vessel to the target pressure at once is required. In addition, when transferring (X) from a pressure-resistant container in which the liquid mixture (X) is prepared to another receiving container in which the liquid mixture (X) is adjusted to a target pressure, a nozzle and a receiving container having a diameter capable of transferring the liquid mixture (X) are provided. A regulator that maintains the same pressure is required. However, in the latter case, a regulator is not required if the pressure in the receiving container is atmospheric pressure.
The temperature and pressure in the pressure resistant container containing the mixed liquid (X) before volume expansion are not particularly limited as long as the filler particles (e1) having a target volume average particle diameter can be obtained. 20 MPa is preferable, and the temperature is preferably 50 to 120 ° C.

The mixing of the filler (e) and the compressed fluid can be continuously performed by a line blend (in-line mixing) method, in addition to the method in the pressure vessel described above, to improve productivity, stabilize quality, and reduce manufacturing space. This is preferable in terms of reduction.
Specific examples of apparatuses used in the line blending method include static inline mixers such as static mixers, inline mixers, lamond super mixers, and sulzer mixers, and stirring inline mixers such as vibrator mixers and turbo mixers. It is done. There are no limitations on the length and pipe diameter of the mixer portion of the apparatus and the number of mixing apparatuses (elements), but they must be able to withstand the target pressure.
The outlet of the apparatus used for the line blending method is preferably provided with a nozzle for taking out the mixture, similar to the pressure vessel.

  EXAMPLES The present invention will be further described below with reference to examples, but the present invention is not limited thereto. In the following description, “parts” indicates parts by weight.

<Examples (1) to (7)> (Production of filler particle-dispersed polyol composition)
After blending (a-1) to (a-2) and (e-1) to (e-2) according to the ratio shown in Table 1, in a pressure resistant reaction vessel in which a stir bar and a thermometer were set, The pressure-resistant reaction vessel was charged to 40% of the volume, sealed and heated with stirring, and the system temperature was raised to 90 ° C. After raising the temperature, carbon dioxide was supplied to 15 MPa, and the mixture was stirred for 10 minutes. Then, the nozzle attached to the lower part of the container was fully opened and opened to obtain a pre-dispersion liquid 1. The pre-dispersion liquid 1 is again charged in a pressure-resistant reaction vessel, adjusted to 90 ° C., supplied with carbon dioxide and stirred at 15 MPa for 10 minutes, and then the nozzle attached to the bottom of the vessel is fully opened and opened to disperse the filler particles. Polyol compositions (A1) to (A7) for rigid urethane foam were obtained.
Table 1 shows the volume average particle diameter of the filler particles (e1) measured with a laser diffraction / scattering particle size distribution analyzer [“LA-920” manufactured by Horiba, Ltd.].

<Comparative Examples (1) to (3)> (Production of Comparative Filler Particle-Dispersed Polyol Composition)
According to the ratio shown in Table 1, after blending (a-1) to (a-2) and (e-1) to (e-2), a sand grinder mill filled with glass beads of 0.5 mmφ Was used for crushing / pulverizing / dispersing to obtain polyol compositions (A′1) to (A′3) for rigid urethane foam in which filler particles were dispersed.
Table 1 shows the volume average particle diameters of the filler particles measured with a laser diffraction / scattering particle size distribution analyzer [“LA-920” manufactured by Horiba, Ltd.].

<Examples 1 to 10, Comparative Examples 1 to 4> (Production of rigid urethane foam)
[Explanation of used raw material symbols]
The raw materials for the rigid urethane foam other than the polyol composition (A) or (A ′) in Examples 1 to 10 and Comparative Examples 1 to 4 are as follows.
(1) Polyol (a)
(A-1) Ester polyol having a number average active hydrogen-containing functional group number of 2 and a hydroxyl value of 250 [Maximol RFK-505 (manufactured by Kawasaki Chemical Industry Co., Ltd.)]
(A-2) PO adduct of glycerin, hydroxyl value 280
(2) Filler (e)
(E-1): Hydrophobic silica R972 (manufactured by Nippon Aerosil)
(E-2): Montmorillonite Kunipia F (manufactured by Kunimine Industries)
(3) Foaming agent (c)
(C-1) Water (c-2) “HFC-245fa” (1,1,1,3,3-pentafluoropropane) manufactured by Central Glass Co., Ltd.
(4) Urethane catalyst (d)
(D-1) Catalyst A (DabcoK-15 manufactured by Air Products Japan Co., Ltd.)
(D-2) Catalyst B (DabcoTMR manufactured by Air Products Japan Co., Ltd.)
(D-3) Amine catalyst C (Dabco33LV manufactured by Air Products Japan Co., Ltd.)
(5) Additive (f)
(F-1) “TMCPP” manufactured by Daihachi Chemical Industry Co., Ltd. [Tris (β-chloropropyl) phosphate]
(F-2) Polyether siloxane polymer (“SH-193” manufactured by Toray Dow Corning Co., Ltd.)
(6) Organic polyisocyanate (b)
(B-1) Crude MDI (“MR-200” manufactured by Nippon Polyurethane Industry Co., Ltd.), NCO% = 31.5)

The manufacturing method of the rigid urethane foam in an Example is as follows.
Predetermined amounts of polyol composition (A), polyol (a), foaming agent (c), urethanization catalyst (d) and additive (f) adjusted to 20 ± 5 ° C. in the number of parts shown in Table 2. Blended to make a polyol premix. An organic polyisocyanate (b) whose temperature was adjusted to 20 ± 5 ° C. was added to this polyol premix so as to have a predetermined isocyanate index, and rapidly mixed at 8000 rpm × 7 seconds with a stirrer [Homodisper: made by Primex]. Thereafter, the temperature was adjusted to 60 ° C., the mixed solution was immediately poured into a 300 × 300 × 40 mm mold, and the mold was foamed to obtain a rigid urethane foam.

  The rigid urethane foams obtained in each of the examples and comparative examples were cut after curing for one day, and the molded product density (according to JIS A9511) and heat insulating property (thermal conductivity) (according to the following method) were measured. Then, it was left to stand at 70 ° C. and a humidity of 95% RH for 2 weeks, and the heat insulating property (thermal conductivity) was measured again, and the gas barrier property was evaluated from the rate of change of the thermal conductivity. The evaluation results are shown in Table 2.

<Measurement method of thermal conductivity>
In accordance with JIS A1412-2, a rigid urethane foam of 300 (length) x 300 (width) x 50 (thickness) mm obtained by mold foaming is sized to 200 (length) x 200 (width) x 35 (thickness) mm. Cut out. Thereafter, the thermal conductivity was measured using a thermal conductivity measuring device “AUTO-Λ HC-074” by Eihiro Seiki Co., Ltd.

  As shown in Table 1, in the example, the volume average particle size of the filler particles (e1) can be reduced as compared with the comparative example. As a result, as shown in Table 2, it is possible to obtain a urethane foam excellent in gas barrier properties in which the time-dependent change in the heat insulation performance of the foam is small.

  The urethane foam produced by the method of the present invention can be used for applications in which urethane foam is usually used. However, since it is excellent in moldability and gas barrier properties, it can be suitably used, for example, as a rigid foam for building materials.

Claims (4)

  Volume expansion of a mixture containing filler (e) and compressed fluid selected from silica, montmorillonite and mixtures thereof, or a mixture (X) containing filler (e), polyol (a) and compressed fluid, and volume average Filler particles (e1) in a urethane foam comprising a step of obtaining filler particles (e1) having a particle size of 10 to 1000 nm, wherein the compressed fluid contains a liquid, subcritical fluid or supercritical fluid obtained by compressing carbon dioxide. ) In which urethane foam is dispersed.   Furthermore, the polyol (a) and the organic polyisocyanate (b) are reacted in the presence of the filler particles (e1), the foaming agent (c) and the urethanization catalyst (d), and the filler particles (e1) The method for producing a urethane foam according to claim 1, comprising a step of using a filler particle-dispersed polyol composition in which is dispersed in at least a part of the polyol (a).   The method for producing a urethane foam according to claim 2, wherein the amount of the filler particles (e1) relative to the total weight of the polyol (a) is 0.1 to 30% by weight.   A filler (e) selected from silica, montmorillonite, and a mixture thereof, and a liquid mixture (X1) containing a polyol (a) and a compressed fluid are volume-expanded, and the volume average particle diameter is 10 to 1000 nm in the polyol (a). A method for producing a filler particle-dispersed polyol composition to obtain a polyol composition in which filler particles (e1) are dispersed.