JP2009035685A - Polyol composition for rigid polyurethane foam and method for producing rigid polyurethane foam - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polyol composition for producing pentane-foamed rigid polyurethane foams excellent in heat-insulating performance, and to provide a method for producing a pentane-foamed rigid polyurethane foam. <P>SOLUTION: This polyol composition for producing the pentane-foamed rigid polyurethane foams, which comprises a polyol compound and a foaming agent and is mixed and reacted with polyisocyanate compounds to form the pentane-foamed rigid polyurethane foams, is characterized in that the foaming agent comprises a pentane compound and water, and the polyol compound contains crystalline zeolite containing at least one selected from the group consisting of krypton, xenon and an HFC compound. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a polyol composition and a method for producing a rigid polyurethane foam for producing a rigid polyurethane foam excellent in heat insulation performance using pentanes and water as a foaming agent component.

  Rigid polyurethane foam is a well-known material as a heat insulating material, a lightweight structural material, and the like. Such a rigid polyurethane foam is formed by mixing and reacting a polyol composition containing a polyol compound and a foaming agent as essential components with a polyisocyanate component, followed by foaming and curing.

  In recent years, from the viewpoint of energy saving, it has become an important issue to reduce the thermal conductivity of the hard polyurethane foam after foaming and improve the heat insulation performance. Basically, in order to improve the heat insulation performance of rigid polyurethane foam, it is important to reduce the thermal conductivity of the gas component in the foam cell, and filling the foam cell with a gas component having a low thermal conductivity is effective. It has been regarded as an appropriate means. For this reason, chlorofluorocarbon compounds such as CFC-11 having a low thermal conductivity have been used as foaming agents for a long time. However, CFC compounds are prohibited because they cause destruction of the ozone layer, switched to HCFC-141b, and since 2004, switching to HFC compounds having an ozone layer depletion coefficient of zero has been performed. Has the problem of being expensive.

  Instead of halogenated hydrocarbon compounds such as HFC compounds, the ozone depletion coefficient is zero, the impact on global warming is extremely small, and pentane such as n-pentane, iso-pentane, cyclopentane, etc. as a low-cost blowing agent The technique of using a combination of water and water is known. However, in such a configuration, carbon dioxide gas having a high thermal conductivity remains at a high ratio in the foam cell, so that the heat insulation performance of the rigid polyurethane foam tends to deteriorate.

  In view of the above problem, as a means for improving the heat insulation performance of the rigid polyurethane foam by removing the carbon dioxide gas in the foam cell, for example, in Patent Document 1, an adsorbent composed of zeolite or the like is added and mixed in the raw material in advance, A method has been proposed in which the generated carbon dioxide gas is adsorbed and removed by an adsorbent and the foam cell is filled with a chlorofluorocarbon gas to improve the heat insulation performance.

  However, in the above method, the adsorbent composed of zeolite or the like selectively adsorbs moisture over carbon dioxide adsorption, and the reaction between the polyisocyanate component and water does not occur sufficiently. There is little heat generation at the initial stage of foaming due to the reaction heat of Therefore, when pentane having a high boiling point is used as a foaming agent, the pentane cannot be sufficiently vaporized, and foam foaming efficiency is lowered, so that a foam having a narrow cell diameter distribution and few voids cannot be obtained.

  For example, Patent Document 2 describes that a rigid polyurethane foam is obtained by mixing and foaming a polyol component and an isocyanate component mixed with zeolite impregnated with cyclopentane as a foaming agent and water.

However, in the above method, although cyclopentane, which is a highly flammable and flammable material, has the effect of reducing the risk of fire or explosion, which becomes a problem when using cyclopentane as a blowing agent, cyclopentane, which is a blowing agent, is used. Compared to the case where the zeolite is not impregnated, the heat insulation performance of the hard polyurethane obtained after foaming / curing is not improved.
JP 57-49628 A JP-A-8-157636

  The objective of this invention is providing the manufacturing method of the polyol composition and pentane foaming rigid polyurethane foam for manufacturing the pentane foaming rigid polyurethane foam excellent in the heat insulation performance.

  As a result of intensive studies to solve the above problems, the present inventors have found that the above object can be achieved by the composition shown below, and have completed the present invention.

  That is, the polyol composition for rigid polyurethane foam of the present invention is a polyol composition for rigid polyurethane foam for forming a rigid polyurethane foam by mixing and reacting with a polyisocyanate component, including a polyol compound and a foaming agent, The blowing agent contains pentanes and water, and the polyol compound contains crystalline zeolite containing at least one selected from the group consisting of krypton, xenon and HFC compounds.

  The rigid polyurethane foam obtained by using the polyol composition having the above-described configuration is a rigid polyurethane foam having excellent heat insulation performance and further suppressing deterioration of heat insulation performance over time. The reason why such an effect is obtained is that the polyol compound contains crystalline zeolite containing at least one selected from the group consisting of krypton, xenon, and HFC compound, and therefore, krypton having low thermal conductivity due to heat generation during foam foaming, It is assumed that the xenon and / or HFC compound is gasified and filled in the foam cell. In addition to the above reasons, the gasification of krypton, xenon and / or HFC compound cavitates the pores of the crystalline zeolite, and carbon dioxide gas with high thermal conductivity is adsorbed and removed into the voids. It is presumed that it becomes possible to suppress deterioration of the heat insulation performance not only in the initial stage but also with time.

  In addition, when crystalline zeolite is added to a polyol composition containing pentanes and water as a blowing agent, water is usually selectively adsorbed and removed by the crystalline zeolite. As a result, it is considered that the heat generation at the initial stage of foaming due to the reaction heat between the polyisocyanate component and water is reduced, the pentane cannot be sufficiently vaporized, and the foam foaming efficiency is lowered. However, in the present invention, since the crystalline zeolite contains at least one selected from the group consisting of krypton, xenon, and HFC compounds, it becomes saturated and the adsorption ability between the crystalline zeolite and water is lost in advance. Does not inhibit the reaction between the ingredients and water. For this reason, the heat generation at the initial stage of foaming due to the heat of reaction between the polyisocyanate component and water is unlikely to decrease. Thereby, since pentane vaporizes sufficiently and suppresses the reduction in foam foaming efficiency, it is presumed that a foam having a narrow cell diameter distribution and few voids can be obtained.

  The content of the crystalline zeolite containing at least one selected from the group consisting of krypton, xenon and HFC compound is 5 to 40 parts by weight with respect to 100 parts by weight of the total of the polyol composition and the polyisocyanate component. As a result, the carbon dioxide gas present in the foam cell after foaming is adsorbed and removed, and a rigid polyurethane foam with higher heat insulation performance is obtained.

  In addition, when the content of at least one selected from the group consisting of krypton, xenon, and HFC compound with respect to the crystalline zeolite is 5 to 20% by weight, the strength and dimensional stability, etc. are maintained well, and the heat insulation is further improved. A rigid polyurethane foam with high performance is obtained.

  Another aspect of the present invention is a method for producing a rigid polyurethane foam, wherein a polyol composition containing a polyol compound and a foaming agent and a polyisocyanate component are mixed to form a foamed stock solution composition, and the foamed stock solution composition is foamed and cured. The foaming agent contains pentane and water, and the polyol compound contains a crystalline zeolite containing at least one selected from the group consisting of krypton, xenon and HFC compound. It relates to the manufacturing method.

  With the above configuration, it is possible to produce a rigid polyurethane foam having high heat insulation performance and further suppressing deterioration of heat insulation performance over time. In the above configuration, the crystalline zeolite containing at least one selected from the group consisting of krypton, xenon, and HFC compound is included in the polyol composition. It is possible to produce a rigid polyurethane foam having high performance and further suppressing deterioration of heat insulation performance over time.

  The crystalline zeolite contained in the polyol compound of the present invention is an aluminosilicate crystalline material, has fine pores in the crystal, and the crystal structure and adsorption performance vary depending on the chemical composition. Crystalline zeolites include pellets and powders. When powdery crystalline zeolite is used, it is preferable because it disperses in the polyol composition without agglomeration. In order to adsorb and remove moisture and carbon dioxide, the pore diameter of the crystalline zeolite is preferably 0.30 nm to 1.2 nm, more preferably 0.40 nm to 1.2 nm.

  The crystalline zeolite contains at least one selected from the group consisting of krypton, xenon and HFC compounds. The content of the crystalline zeolite containing at least one selected from the group consisting of krypton, xenon, and HFC compound is 5 to 40 parts by weight with respect to 100 parts by weight of the total of the polyol composition and the polyisocyanate component. The amount is preferably 10 to 30 parts by weight. If the amount is less than 5 parts by weight, sufficient effect of improving the heat insulation performance cannot be obtained. If the amount exceeds 40 parts by weight, the cell surface of the hard polyurethane foam after foaming / curing may occur and the foam appearance may be deteriorated. At the same time, since the thermal conductivity of the crystalline zeolite itself is higher than that of the gas component, the heat insulating performance of the foam tends to deteriorate.

  The crystalline zeolite containing at least one selected from the group consisting of krypton, xenon, and HFC compound is obtained by, for example, immersing the crystalline zeolite in krypton, xenon and / or HFC compound, and adding krypton, xenon and / or HFC compound. It is obtained by impregnating and adsorbing to crystalline zeolite. Examples of the HFC compound include 1,1,1,3,3-pentafluoropropane (HFC-245fa), 1,1,1,3,3-pentafluorobutane (HFC-365mfc), and the like.

  The content of at least one selected from the group consisting of krypton, xenon and HFC compound with respect to the crystalline zeolite is preferably 5 to 20% by weight. If it is less than 5% by weight, the crystalline zeolite is not saturated with krypton, xenon and / or HFC compound, the adsorption of the crystalline zeolite and water occurs, and foaming is caused by the heat of reaction between the polyisocyanate component and water. Initial heat generation is reduced. As a result, foam foaming efficiency tends to decrease, which is not preferable. On the other hand, if it exceeds 20% by weight, the product density of the rigid polyurethane foam obtained after foaming and curing is lowered, and sufficient foam physical properties (strength and dimensional stability, etc.) tend not to be maintained, which is not preferable.

  Crystalline zeolites are widely marketed as molecular sieves, for example, molecular sieves made by Union Showa (adsorption types 4A, 5A and 13X) can be mentioned, and as an adsorption type, from the viewpoint of more effectively adsorbing carbon dioxide gas, Those of 5A and 13X are preferred. Moreover, what carried out the hydrophobic process to the molecular sieve can also be used, and the union Showa Co., Ltd. molecular sieve (HiSiv) is mentioned as a commercial item, for example.

  Moreover, in the polyol compound of this invention, a well-known polyol can be used without limitation in the technical field of rigid polyurethane foam. Examples of the polyol include aromatic polyester polyols, aromatic amine polyether polyols, and aliphatic amine polyether polyols.

  As the aromatic polyester polyol, those for known resin foams can be used without limitation. For example, phthalic acids such as terephthalic acid, phthalic acid, and isophthalic acid, trimellitic acid, ethylene glycol, diethylene glycol, 1, Examples thereof include ester polyols having hydroxyl groups with polyhydric alcohols such as 4-butanediol, dipropylene glycol, and polyoxyalkylene glycol. The average functional group number of the aromatic polyester polyol compound is preferably 2 to 3 and more preferably 2 to 2.5 from the viewpoint of suppressing an increase in the viscosity of the polyol composition. The hydroxyl value of the aromatic polyester polyol is preferably 200 to 450 mgKOH / g from the standpoint of suppressing the increase in viscosity of the polyol composition and ensuring the foam strength of the hard polyurethane foam after foaming and curing. More preferably, it is 200-300 mgKOH / g. In addition, the aromatic concentration is preferably 20% or more from the viewpoint of improving the heat insulation performance.

  Further, the blending amount of the aromatic polyester polyol is preferably 30 to 70 parts by weight, and further 35 to 60 parts by weight with respect to 100 parts by weight of the total polyol compound, since the heat insulating performance and flame retardancy of the foam are improved. .

  The aromatic amine-based polyether polyol is a polyol compound obtained by ring-opening addition of a cyclic ether compound such as ethylene oxide, propylene oxide, butylene oxide using an aromatic diamine as an initiator. As aromatic diamine which is an initiator, well-known aromatic diamine can be used without limitation. Specific examples include 2,4-toluenediamine, 2,6-toluenediamine, diethyltoluenediamine, 4,4'-diaminodiphenylmethane, p-phenylenediamine, o-phenylenediamine, naphthalenediamine and the like. Among these, use of toluenediamine (2,4-toluenediamine, 2,6-toluenediamine, or a mixture thereof) is preferable in that the obtained rigid polyurethane foam has excellent properties such as heat insulation and strength.

  The hydroxyl value of the aromatic amine-based polyether polyol should be 300 to 600 mgKOH / g from the standpoint of suppressing the viscosity increase of the polyol composition and ensuring the foam strength of the rigid polyurethane foam after foaming and curing. Preferably, it is 400-550 mgKOH / g. The blending amount of the aromatic polyester polyol is preferably 10 to 40 parts by weight, more preferably 10 to 30 parts by weight, based on 100 parts by weight of the total polyol compound, since the heat insulation performance and flame retardancy of the foam are improved.

  Examples of the aliphatic amine-based polyether polyol include alkylene diamine-based polyols and alkanolamine-based polyols. These polyol compounds are polyfunctional polyol compounds having a terminal hydroxyl group obtained by ring-opening addition of at least one of ethylene oxide and propylene oxide using alkylene diamine or alkanol amine as an initiator. As the alkylene diamine, known compounds can be used without limitation. Specifically, use of alkylene diamine having 2 to 8 carbon atoms such as ethylene diamine, propylene diamine, butylene diamine, hexamethylene diamine, and neopentyl diamine is preferable. Among these, the use of alkylenediamine having a small number of carbon atoms is more preferable, and the use of a polyol compound having ethylenediamine or propylenediamine as an initiator is particularly preferable. In the alkylene diamine-based polyol, the alkylene diamine as the initiator may be used alone or in combination of two or more. Examples of the alkanolamine include monoethanolamine and diethanolamine.

  The hydroxyl value of the aliphatic amine-based polyether polyol should be 500 to 850 mgKOH / g from the standpoint of suppressing the increase in viscosity of the polyol composition and ensuring the foam strength of the rigid polyurethane foam after foaming and curing. Preferably, it is 600-810 mgKOH / g. The blending amount of the aromatic polyester polyol is preferably 10 to 50 parts by weight, more preferably 10 to 40 parts by weight with respect to 100 parts by weight of the total polyol compound, since the heat insulation performance and flame retardancy of the foam are improved.

  You may add a crosslinking agent to the polyol composition of this invention. As the crosslinking agent, low molecular weight polyhydric alcohols used in the technical field of polyurethane can be used. Specifically, trimethylolpropane, glycerin, pentaerythritol and the like are exemplified.

  In the production of the rigid polyurethane foam of the present invention, catalysts, foam stabilizers, flame retardants, low viscosity assistants, colorants, antioxidants and the like known to those skilled in the art can be used.

  Examples of the catalyst include triethylenediamine, N-methylmorpholine, N, N, N ′, N′-tetramethylethylenediamine, N, N, N ′, N′-tetramethylhexamethylenediamine (Kaorizer No. 1), diaza It is preferable to use tertiary amines such as bicycloundecene (DBU) and N, N-dimethylcyclohexylamine (Polycat-8). In particular, it is preferable to use N, N, N ′, N′-tetramethylhexamethylenediamine.

  In the present invention, it is also preferable to use a trimerization catalyst that forms an isocyanurate bond that contributes to an improvement in flame retardancy in the structure of the polyurethane molecule in addition to the urethanization reaction promoting catalyst. For example, potassium acetate, potassium octylate (trade names) Examples thereof include aliphatic carboxylic acid potassium salts and quaternary ammonium salts such as Perlon 9540). As the quaternary ammonium salt, conventionally known quaternary ammonium salts can be used without limitation. For example, tetraalkylammonium halides such as tetramethylammonium chloride, tetraalkylammonium hydroxides such as tetramethylammonium hydroxide, tetra Examples thereof include tetraalkylammonium organic acid salts such as methylammonium 2-ethylhexanoate, 2-hydroxypropyltrimethylammonium formate, and 2-hydroxypropyltrimethylammonium 2-ethylhexanoate.

  In the present invention, it is preferable to use a trimerization catalyst that promotes isocyanurate bond formation and an amine catalyst that promotes urethane bond formation. In particular, it is preferable to use potassium octylate and / or a quaternary ammonium salt as the trimerization catalyst and N, N-dimethylcyclohexylamine as the amine catalyst. When potassium octylate and a quaternary ammonium salt are used in combination as a trimerization catalyst, the blending weight ratio is preferably the former / the latter = 1/2 to 2/1. Moreover, when using together an amine catalyst and a trimerization catalyst, it is preferable that the compounding weight ratio is an amine catalyst / trimerization catalyst = 10/3-20/1.

  In the present invention, addition of a flame retardant is also a preferred embodiment, and examples of suitable flame retardants include metal compounds such as halogen-containing compounds, organic phosphate esters, and aluminum hydroxide.

  Organophosphates are suitable additives because they also have an action as a plasticizer and thus have an effect of improving the brittleness of rigid polyurethane foam. It also has the effect of reducing the viscosity of the polyol composition. Examples of the organic phosphate esters include halogenated alkyl esters of phosphoric acid, alkyl phosphate esters, aryl phosphate esters, phosphonate esters, and the like. Specifically, tris (β-chloroethyl) phosphate (CLP, Daihachi Chemical), Tris (β-chloropropyl) phosphate (TMCPP, Daihachi Chemical), Tributoxyethyl phosphate (TBXP, Daihachi Chemical), Tributyl phosphate, Triethyl phosphate, Cresyl phenyl phosphate, Dimethyl methylphosphonate Etc., and one or more of these can be used. The amount of the organic phosphate ester added is preferably 40 parts by weight or less, more preferably 10 to 20 parts by weight, based on 100 parts by weight of the total polyol compound. If this range is exceeded, problems such as insufficient plasticization and flame retardant effects and deterioration of the mechanical properties of the foam may occur.

  The pentane used as the foaming agent is appropriately selected from one or more of n-pentane, isopentane, and cyclopentane. In addition, in this invention, in order to adjust the product density of the rigid polyurethane foam obtained after foaming and hardening, you may adjust suitably the addition amount of pentanes and water used as a foaming agent. However, reducing the amount of water added tends to reduce the strength of the rigid polyurethane foam obtained after foaming / curing, and increasing the amount of water added decreases the density of the rigid polyurethane foam obtained after foaming / curing. It is preferable to add 1-3 parts by weight of water with respect to 100 parts by weight of the polyol compound.

  The polyisocyanate compound that forms a rigid polyurethane foam by mixing and reacting with the polyol composition is easy to handle, fast in reaction, excellent in the physical properties of the resulting rigid polyurethane foam, and low in cost. For this reason, liquid MDI is used. As liquid MDI, Crude MDI (c-MDI) (Sumijoule 44V-10, Sumijoule 44V-20, etc. (manufactured by Sumika Bayer Urethane Co., Ltd.), Millionate MR-200 (Nippon Polyurethane Industry)), uretonimine-containing MDI (Millionate) MTL (manufactured by Nippon Polyurethane Industry) or the like is used. In addition to liquid MDI, other polyisocyanate compounds may be used in combination. As the polyisocyanate compound to be used in combination, polyisocyanate compounds well known in the technical field of polyurethane can be used without limitation.

  In the production of the rigid polyurethane foam of the present invention, the equivalent ratio of isocyanate groups to active hydrogen groups (NCO index) is preferably 1.1 to 1.8, more preferably 1.1 to 1.6. is there.

The polyol composition and rigid polyurethane foam production method of the present invention can be used for producing continuously produced foams such as slabstock foams and sandwich panels. The product density of the obtained rigid polyurethane foam is preferably 22 to 50 kg / m ³ .

  The method for producing a rigid polyurethane foam of the present invention will be described by taking as an example the production of a heat insulating panel in which paper materials are laminated on both sides. In the method for producing a rigid polyurethane foam of the present invention, a face material supply device, a conveyor device, a polyol composition and a polyisocyanate component, which are generally used for producing a slab foam or a sandwich panel, are mixed on the bottom material. A known continuous foaming apparatus equipped with a foaming machine (mixer) to be fed to a heating oven, a heating oven, and a cutting machine for cutting a rigid polyurethane foam formed into a continuous shape into an appropriate length can be used.

The manufacturing process of the sandwich panel is generally composed of the following processes.
1) The lower sheet surface material is rewound from the original roll and supplied to the conveyor.
2) A foaming stock solution composition formed by mixing a polyol composition and a polyisocyanate component in a foaming machine on a lower paper surface material is uniformly supplied in the width direction of the paper surface material.
3) Supply the upper paper surface material. After supplying the top surface material, it passes through a nip device such as a nip roll to diffuse the foamed stock solution composition in the width direction, make the thickness of the solution uniform, and make the top and bottom surface material and the foamed stock solution composition compatible.
4) It is sent to a heating oven and heated to cause a foaming / curing reaction, thereby obtaining a rigid polyurethane foam having paper materials laminated on both sides. In order to obtain a predetermined thickness, a double conveyor that holds the upper and lower surfaces of the foam may be used.
5) The rigid polyurethane foam continuously coming out of the heating oven is cut into a predetermined length by a cutting machine.

  The rigid polyurethane foam sandwich panel has a width of 1300 mm or less, a thickness of 10 to 60 mm when it is thin, and a thickness of 60 to 150 mm when it is thick, and is appropriately set according to the application. The face material to be used is not particularly limited. In the case of a paper face material, kraft paper having a thickness of 0.3 to 2.0 mm is used.

<Raw materials>
(1) Polyol compound / Polyol A: PO adduct of ethylenediamine (Asahi Glass Co., Ltd., hydroxyl value 760 mgKOH / g)
Polyol B: Aromatic polyester polyol (manufactured by Hitachi Chemical Co., Ltd., hydroxyl value 250 mgKOH / g, number of functional groups 2, aromatic concentration 24.0%)
Polyol C: EO and PO adduct of toluenediamine (Asahi Glass Co., Ltd., hydroxyl value 450 mgKOH / g)
(2) Crystalline zeolite molecular sieve 13X (Union Showa)
(3) Flame retardant (plasticizer): TMCPP (manufactured by Daihachi Chemical Industry Co., Ltd.)
(4) Foam stabilizer: SH-193: Silicone surfactant (Toray Dow Corning Silicone)
(5) Amine catalyst: N, N, N ′, N′-tetramethylhexamethylenediamine (Kaorizer No. 1, manufactured by Kao Corporation)
(6) Trimerization catalyst: potassium octylate (Perlon 9540, manufactured by Perlon)
(7) Foaming agent: pentanes (cyclopentane), water (8) polyisocyanate compound: Sumidur 44V-20 (manufactured by Sumika Bayer Urethane Co., Ltd.)
<Production example of rigid polyurethane foam>
(Examples 1-12, Comparative Examples 1-2)
Molecular sieve 13X containing krypton, xenon, or HFC-245fa in the polyol compound having the composition described in Table 1 (the content of krypton with respect to molecular sieve 13X is 10 to 20% by weight, and the content of xenon is 5 to 20% by weight , HFC-245fa content is 10 to 20% by weight) and mixed well, and then mixed with the polyisocyanate component by a mixer in a sandwich panel continuous production line to obtain a foaming stock solution composition. After the composition was spread on a kraft paper surface material, the top material of the same material was supplied to form a sandwich, foamed and cured to obtain a rigid polyurethane foam sandwich panel having a width of 1300 mm or less and a thickness of 10 to 150 mm (Example) 1-12). Moreover, the rigid polyurethane foam sandwich panel was obtained by the method similar to Examples 1-12 by the composition described in Table 1 (Comparative Examples 1-2).

<Measurement and evaluation method>
(1) Thermal conductivity A thermal conductivity measuring device AUTO-Λ HC-074 (manufactured by Eihiro Seiki Co., Ltd.) was used, and the measurement conditions were measured for thermal conductivity (w / mk) in accordance with JIS A 9511.
(2) Foam density A 100 × 100 × 100 (mm) sample was cut out from the core portion of a rigid polyurethane foam sandwich panel having a width of 1300 mm or less and a thickness of 10 to 150 mm obtained in the above-mentioned rigid polyurethane foam production example. The density was determined by measuring.
(3) Foam appearance The foam state of the rigid polyurethane foam obtained after foaming and curing was visually confirmed. ○ indicates that there is no dimensional change due to shrinkage or the like, and x indicates that there is a dimensional change. Moreover, the cell state of the rigid polyurethane foam obtained after foaming and hardening was confirmed visually. ○ indicates that almost no voids are generated and cell roughness is not confirmed, and × indicates that voids are generated and cell roughness is confirmed. The measurement results are shown in Table 2.

  The rigid polyurethane foams of Examples 1 to 12 obtained by mixing and foaming a polyol composition containing a molecular sieve 13X containing krypton, xenon, or an HFC compound and a polyisocyanate component are compared without containing the molecular sieve 13X. Compared to the rigid polyurethane foam of Example 1, it can be seen that the thermal conductivity after 1 day of foaming and 30 days after foaming is low, the thermal insulation performance at the initial stage of foaming is excellent, and the deterioration of the thermal insulation performance over time is also suppressed. Further, in the rigid polyurethane foam of Comparative Example 2, since the molecular sieve 13X selectively adsorbs and removes water in the polyol composition, cell roughening and cracks occur due to a decrease in foam foaming efficiency. As a result, the foam density And the thermal conductivity could not be measured. On the other hand, in Examples 1 to 12, a rigid polyurethane foam having a narrow cell diameter distribution of foam appearance and almost no voids was obtained without causing cell roughening and cracks.

Claims (5)

A polyol composition for a rigid polyurethane foam comprising a polyol compound and a foaming agent, mixed with a polyisocyanate component and reacted to form a rigid polyurethane foam,
The blowing agent contains pentanes and water,
The polyol composition for rigid polyurethane foam, characterized in that the polyol compound contains a crystalline zeolite containing at least one selected from the group consisting of krypton, xenon and HFC compounds.   The content of the crystalline zeolite containing at least one selected from the group consisting of krypton, xenon, and HFC compound is 5 to 40 parts by weight with respect to 100 parts by weight of the total of the polyol composition and the polyisocyanate component. The polyol composition for rigid polyurethane foam according to claim 1.   The polyol composition for rigid polyurethane foam according to claim 1 or 2, wherein the content of at least one selected from the group consisting of krypton, xenon, and HFC compound with respect to the crystalline zeolite is 5 to 20% by weight. In a method for producing a rigid polyurethane foam, a polyol composition containing a polyol compound and a foaming agent and a polyisocyanate component are mixed to obtain a foamed stock solution composition, and the foamed stock solution composition is foamed and cured.
The blowing agent contains pentanes and water,
The method for producing a rigid polyurethane foam, wherein the polyol compound contains a crystalline zeolite containing at least one selected from the group consisting of krypton, xenon and HFC compounds. In a method for producing a rigid polyurethane foam, a polyol composition containing a polyol compound and a foaming agent and a polyisocyanate component are mixed to obtain a foamed stock solution composition, and the foamed stock solution composition is foamed and cured.
The blowing agent contains pentanes and water,
The method for producing a rigid polyurethane foam, wherein the polyisocyanate component contains a crystalline zeolite containing at least one selected from the group consisting of krypton, xenon and HFC compounds.