JP4058806B2 - Manufacturing method of rigid foam synthetic resin - Google Patents

Description

【００４９】
【表２】

【００５０】
例４〜１０からわかるようにポリエステルポリオール（Ｘ）を所定量使用した場合は、熱伝導率の低い硬質ウレタンフォームが得られ、しかもポリオールシステムは透明で、貯蔵安定性に優れる。
【００５１】
また例１１〜１６からわかるようにポリエステルポリオール（Ｘ）を所定量以外で使用した場合は、熱導率が高くなり断熱性能が劣る、またはポリオールシステムが乳濁し、貯蔵安定性が劣る。
【００５２】
【発明の効果】
発泡剤としてＣＦＣやＨＣＦＣを用いることなく、断熱性に優れた硬質発泡合成樹脂を製造することができる。疎水性の高いシクロペンタン等の低沸点炭化水素やＨＦＣ−２４５ｆａ等のヒドロフルオロカーボンを発泡剤として使用するのにもかかわらず本発明におけるポリオールシステムは貯蔵安定性に優れる。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for producing a hard foamed synthetic resin, in which a polyol system having excellent storage stability is obtained by using a polyol having a specific structure, and a hard foamed synthetic resin having excellent heat insulation is obtained.
[0002]
[Prior art]
Rigid foam synthetic resin such as rigid polyurethane foam is widely used as a heat insulating material for refrigerators, showcases, heat storage warehouses, refrigeration warehouses, etc. due to its excellent heat insulation performance.
Recently, HCFC-141b (1,1-dichloro-1-fluoroethane) or water (CO generated as a by-product in the reaction with isocyanate) is used as a blowing agent to prevent destruction of the ozone layer by specific chlorofluorocarbons.₂ Gas foaming) is used.
[0003]
However, in foaming with water, this CO₂ The use of gas is limited because of its high thermal conductivity, and it is difficult to use it as a heat insulating material for electric refrigerators. With regard to HCFC-141b, the ozone depletion potential (ODP) is as large as 0.11 and the time dependency of this ODP is also large. In fact, the 7th Montreal Protocol Parties Meeting at the end of last year was completely abolished in 2020, 10 years ahead of schedule.
[0004]
Already mainly in Europe, cyclopentane with zero ODP is used as an alternative blowing agent for hydrochlorofluorocarbons such as HCFC-141b. However, while cyclopentane is a highly hydrophobic compound, many polyols for rigid foam synthetic resins are generally highly hydrophilic. Therefore, when cyclopentane is used as a foaming agent, it is necessary to increase the compatibility between the cyclopentane and the polyol for the hard foam synthetic resin. Since the thermal conductivity of cyclopentane is larger than that of HCFC-141b, a device for reducing the thermal conductivity of the rigid foam synthetic resin is also necessary.
[0005]
Hydrofluorocarbons such as 1,1,1,3,3-pentafluoropropane (HFC-245fa) have also been used as alternative blowing agents for hydrochlorofluorocarbons, but these hydrochlorocarbons are also highly hydrophobic compounds. In the case of using a fluorocarbon, the same device as that in the case of using cyclopentane is required.
[0006]
[Problems to be solved by the invention]
As described above, in the production of rigid foamed synthetic resins, particularly in the production of rigid foamed synthetic resins that require heat insulation performance, when using a low-boiling hydrocarbon such as cyclopentane or a hydrofluorocarbon such as HFC-245fa as a foaming agent How to reduce the thermal conductivity of the foam and how to increase the compatibility between the polyol and the foaming agent are important issues. In particular, if the compatibility with polyol is low, a polyol system containing a low-boiling hydrocarbon such as cyclopentane or a foaming agent such as hydrofluorocarbon such as HFC-245fa becomes emulsified, and further, the components of the polyol system are separated in a short time. There will be no sex.
[0007]
On the other hand, in the examination so far, a technique for reducing the thermal conductivity of the rigid foam synthetic resin by using a polyester polyol is also known in the conventional technique using trichlorofluoromethane (CFC-11) as a foaming agent.
[0008]
For example, in JP-A-2-180916, aromatic polyester polyol having an average number of functional groups of 2.2 to 3.6 is used in an amount of 10 to 60% by weight of the polyol component, so that the resin strength and productivity are excellent and the thermal conductivity is reduced. It shows that there is an effect. JP-A-1-101321 shows that a hard foamed synthetic resin exhibiting excellent heat insulation can be obtained by containing 30% by weight or less of a polyester polyol synthesized using an organometallic compound.
However, these use CFC-11 as a foaming agent alone or in combination with water, and a foaming agent containing hydrocarbon or hydrofluorocarbon as an essential component has not been studied yet, and its effect has not been clarified. It was.
[0009]
Furthermore, JP-A-9-132628 uses a foaming agent containing water and cyclopentane as essential components, and a polyester polyol having an average functional group number of 2.0 to 4.0 and a hydroxyl value of 300 to 600 mgKOH / g as a polyol is 70% by weight or more. It shows that there is an effect in reducing thermal conductivity when used. However, in this case, since the polyester polyol that reduces the solubility of cyclopentane in the polyol system is used in an amount of 70% by weight or more, the solubility of cyclopentane in the resin system (polyol system) is remarkably lowered. In the storage stability test at 40 ° C., separation occurs after standing for 3 to 14 days.
[0010]
JP-A-8-104725 discloses a hydroxyl value of 200 to 200 obtained by esterifying an aromatic polycarboxylic acid or its anhydride as a polyol and a bifunctional or trifunctional alcohol containing a hydrocarbon chain having 3 to 12 carbon atoms. 20 to 50% by weight of 400 mg KOH / g aromatic polyester polyol and 80 to 30% by weight of aromatic polyamine polyether polyol having a hydroxyl value of 300 to 600 mg KOH / g obtained by adding alkylene oxide to aromatic polyamine In addition, the use of low-boiling point hydrocarbons as a blowing agent is effective in reducing thermal conductivity and improving compatibility with low-boiling point hydrocarbons. However, the storage stability of the polyol system was still insufficient.
[0011]
[Means for Solving the Problems]
  The present invention has been made to solve the above-mentioned problems, and low boiling point hydrocarbons such as cyclopentane.ElementA rigid foam synthetic resin produced using a foaming agent as an essential component is characterized in that thermal conductivity can be reduced and heat insulation can be improved by using a polyester polyol having a specific molecular structure. . Furthermore, the polyol system in the present invention is characterized by excellent storage stability.
[0012]
  That is, the present invention relates to a method for producing a rigid foamed synthetic resin by reacting an active hydrogen compound having two or more active hydrogen-containing functional groups capable of reacting with an isocyanate group and a polyisocyanate compound in the presence of a foaming agent and a catalyst. , Active hydrogenationThing isThe following polyester polyol (X)Mixture of 10-50 wt% and polyether polyol 90-50 wt%And foaming agentIs charcoal4 to 6 prime hydrocarbonsPlainIt is a manufacturing method of the hard foam synthetic resin characterized by being.
  Polyester polyol (X):Aromatic polycarboxylic acid or its derivative and HOR ¹ OH (R ¹ Is reacted with a diol (y) represented by a polymethylene group having 3 or more carbon atoms or a group in which one or more hydrogen atoms of the group are substituted with an alkyl group having 1 to 5 carbon atoms, A polyester polyol obtained by addition polymerization,A residue of an aromatic polycarboxylic acid, -R¹O-A unit other than the unit (Y) and the unit (Y) represented by -R²O- (R² Is a polyester polyol having a unit (Z) represented by a dimethylene group or a group in which one or more hydrogen atoms of the group are substituted with an alkyl group having 1 to 5 carbon atoms.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
The polyester polyol (X) in the present invention includes an aromatic polycarboxylic acid residue, -R¹ O- (R¹ Is a unit other than the unit (Y) represented by a unit (Y) represented by a polymethylene group having 3 or more carbon atoms or a group in which at least one hydrogen atom of the group is substituted with an alkyl group having 1 to 5 carbon atoms. And -R² O- (R² Is a polyester polyol having a unit (Z) represented by a dimethylene group or a group in which at least one hydrogen atom of the group is substituted with an alkyl group having 1 to 5 carbon atoms.
[0014]
The polyester polyol (X) has an aromatic polycarboxylic acid residue. In the present invention, the aromatic polycarboxylic acid residue means a group obtained by removing a hydrogen atom from a carboxyl group of an aromatic polycarboxylic acid. Examples of the aromatic polycarboxylic acid include phthalic acid, isophthalic acid, terephthalic acid, trimellitic acid, and pyromellitic acid, and phthalic acid is particularly preferable. When the polyester polyol (X) is produced by the method described later, an aromatic polycarboxylic acid derivative may be used. Derivatives include acid anhydrides, alkyl esters or acid chlorides, and acid anhydrides are particularly preferred.
The polyester polyol (X) preferably contains 10 to 70% by weight of an aromatic polycarboxylic acid residue, particularly preferably 20 to 60% by weight.
[0015]
Polyester polyol (X) is -R¹ O- (R¹ Has a unit (Y) represented by a polymethylene group having 3 or more carbon atoms or a group in which at least one hydrogen atom of the group is substituted with an alkyl group having 1 to 5 carbon atoms.
R¹ The total number of carbon atoms is preferably from 3 to 9, and particularly preferably from 4 to 6. When the number of carbon atoms exceeds 9, the thermal conductivity of the foam produced tends to decrease. R¹ Is particularly preferably an unsubstituted polymethylene group having 3 or more carbon atoms, and most preferably an unsubstituted polymethylene group having 4 to 6 carbon atoms.
The polyester polyol (X) preferably contains 5 to 60% by weight of the unit (Y), particularly preferably 10 to 50% by weight.
[0016]
Unit (Y) is HOR¹ OH (R¹ Represents a diol (hereinafter referred to as diol (y)) represented by a polymethylene group having 3 or more carbon atoms or a group in which one or more hydrogen atoms of the group are substituted with an alkyl group having 1 to 5 carbon atoms. It is preferably a unit obtained by reacting by a method. The diol (y) is an alkanediol having 4 to 6 carbon atoms, and is particularly preferably a diol in which carbon atoms bonded with a hydroxyl group are not adjacent to each other. HO (CH₂ )_m Most preferably, it is OH (m is 4-6).
[0017]
Specific examples of the diol (y) include 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, and 2,2-dimethyl. -1,3-propanediol, 2-methyl-2,4-pentanediol. 1,4-butanediol, 1,5-pentanediol, and 1,6-hexanediol are particularly preferable.
[0018]
The polyester polyol (X) is a unit other than the unit (Y), and -R² O- (R² Has a unit (Z) represented by a dimethylene group or a group in which at least one hydrogen atom of the group is substituted with an alkyl group having 1 to 5 carbon atoms.
R² Examples thereof include an ethylene group, a propylene group, a 1,2-dimethylethylene group, and an ethylethylene group. An ethylene group and / or a propylene group are preferred, and an ethylene group is particularly preferred.
[0019]
The polyester polyol (X) preferably contains 5 to 50% by weight of the unit (Z), particularly preferably 10 to 40% by weight. If the amount of the unit (Z) is small, the compatibility with low-boiling hydrocarbons and hydrofluorocarbons is lowered, and the polyol system tends to be suspended and storage stability is liable to deteriorate, which is not preferable.
[0020]
  Unit (Z) is HOR by the following method.²OH (R²Is a diol represented by a dimethylene group or a group in which one or more hydrogen atoms of the group are substituted with an alkyl group having 1 to 5 carbon atoms (hereinafter referred to as diol (z)) or an alkylene oxide. It is preferably a unit obtained by polymerization.In the present invention,It is a unit obtained by ring-opening polymerization of alkylene oxide.The
[0021]
Examples of the diol (z) include ethylene glycol, propylene glycol, 1,2-butylene glycol, and 2,3-butylene glycol.
Examples of the alkylene oxide include ethylene oxide, propylene oxide, 1,2-butylene oxide, 2,3-butylene oxide, and the like, and ethylene oxide, propylene oxide, or a combination of both is preferable. Ethylene oxide or a combination of ethylene oxide and propylene oxide is more preferred, and use of ethylene oxide alone is most preferred.
[0022]
  The polyester polyol (X) is preferably a polyester polyol produced by the following method (1), (2) or (3):In the present inventionWhat is obtained by the method of (1)Select.
[0023]
(1) A method of subjecting an aromatic polycarboxylic acid or a derivative thereof and a diol (y) to an esterification reaction at 150 to 300 ° C. under normal pressure and then addition polymerization of alkylene oxide.
In the esterification reaction, a catalyst may or may not be used. When used, a known esterification catalyst or transesterification catalyst such as calcium acetate, magnesium acetate, or alkyltin can be used. The addition polymerization reaction of alkylene oxide is preferably performed at 50 to 130 ° C, particularly preferably at a temperature of 80 to 140 ° C.
[0024]
(2) Aromatic polycarboxylic acid or a derivative thereof and alkylene oxide are reacted with carboxylic acid at a ratio of less than equivalent equivalent of alkylene oxide, then reacted with diol (y), and then optionally subjected to addition polymerization of alkylene oxide. how to.
(3) A diol (y) and a diol (z) are reacted with an aromatic polycarboxylic acid or a derivative thereof.
[0025]
  The hydroxyl value of the polyester polyol (X) in the present invention is preferably 200 to 600 mgKOH / g, particularly preferably 200 to 400 mgKOH / g.
  The amount of polyester polyol (X) used is in the active hydrogen compound.10-50% By weight. If it is less than 5% by weight, there is no effect in improving the heat insulation property of the hard foam synthetic resin, and if it exceeds 60% by weight, the storage stability of a polyol system in which a catalyst, a foam stabilizer, a foaming agent, etc. are added to an active hydrogen compound. Decreases. 10 to 50% by weight is preferable, and 10 to 40% by weight is particularly preferable.
[0026]
  In the present invention, polyols other than polyester polyol (X), polyhydric phenols, and polyhydric amines can be used as the active hydrogen compound. Examples of polyols other than polyester polyol (X) include polyether polyols and polyhydric alcohols,In the present invention,A polyether polyol is selected. The polyether polyol is obtained by addition polymerization of alkylene oxide with an initiator such as a hydroxy compound in the presence of a catalyst.
  The amount of the polyether polyol used is 50 to 90% by weight in the active hydrogen compound.And60 to 90% by weight is particularly preferred.
[0027]
As the initiator, ethylene glycol, propylene glycol, diethylene glycol, dipropylene glycol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 2,3-butane Diol, 1,5-pentanediol, 1,6-hexanediol, 2,2-dimethyl-1,3-propanediol, 2-methyl-2,4-pentanediol, cyclohexanedimethanol, glycerin, trimethylolpropane, Polyethanols such as diethanolamine, triethanolamine and pentaerythritol, saccharides such as sorbitol and sucrose, phenols such as bisphenol A, amines such as monoethanolamine, ethylenediamine, diaminodiphenylmethane, and tolylenediamine It is below. These may be used as a mixture.
[0028]
Examples of the alkylene oxide that undergoes addition polymerization to the initiator include ethylene oxide, propylene oxide, 1,2-butylene oxide, 2,3-butylene oxide, and styrene oxide. Ethylene oxide, propylene oxide, or a combination of both is preferable. More preferred is ethylene oxide or a combination of ethylene oxide and propylene oxide. When two or more kinds of alkylene oxides are used in combination, they may be subjected to addition polymerization sequentially or randomly. The addition polymerization reaction of alkylene oxide is preferably performed at 50 to 130 ° C, particularly preferably at a temperature of 80 to 140 ° C.
[0029]
The hydroxyl value of the polyether polyol is preferably from 100 to 1000 mgKOH / g, particularly preferably from 200 to 600 mgKOH / g. The polyether polyol may be a mixture of two or more. It is particularly preferable that a polyether polyol produced using diaminodiphenylmethane or tolylenediamine as an initiator is essential.
[0030]
The polyisocyanate compound used in the present invention includes aromatic and aliphatic polyisocyanates having two or more isocyanate groups and modified products obtained by modifying them. Specifically, polyisocyanates such as tolylene diisocyanate, diphenylmethane diisocyanate, polymethylene polyphenylene polyisocyanate (common name: Crude MDI), xylylene diisocyanate, isophorone diisocyanate, hexamethylene diisocyanate, etc. And urea modified products. Diphenylmethane diisocyanate, polymethylene polyphenylene isocyanate and their modified products are particularly preferred.
[0031]
  DepartureThe foaming agent is selected from the group consisting of hydrofluorocarbons and hydrocarbons having 4 to 6 carbon atoms.In the present invention, a hydrocarbon having 4 to 6 carbon atoms is selected.The hydrofluorocarbon means a fluorinated hydrocarbon composed of three elements, hydrogen, fluorine and carbon.
[0032]
Examples of the hydrofluorocarbon include 1,1,1,2-tetrafluoroethane (HFC-134a), 1,1,1,4,4,4-hexafluorobutane (HFC-356mff), 1,1,1,2- Tetrafluoropropane (HFC-245eb), 1,1,2,2,3-pentafluoropropane (HFC-245ca), 1,1,1,3,3-pentafluoropropane (HFC-245fa), 1,1 1,3-tetrafluoropropane (HFC-254fb) and the like. Of these, HFC-245fa and HFC-134a are preferred from the viewpoints of boiling point and low thermal conductivity.
[0033]
The amount of hydrofluorocarbon used is preferably 10 to 50 parts by weight, particularly preferably 20 to 45 parts by weight, based on 100 parts by weight of the active hydrogen compound (excluding water when water is used).
[0034]
Examples of the hydrocarbon include butane, n-pentane, neopentane, isopentane, cyclopentane, hexane, cyclohexane and the like. Cyclopentane is particularly preferred from the viewpoint of low thermal conductivity. The amount of hydrocarbon used is preferably 5 to 30 parts by weight per 100 parts by weight of the active hydrogen compound (excluding water when water is used).
[0035]
In the present invention, it is particularly preferable to use water as a foaming agent. The amount of water used is preferably 0.01 to 10 parts by weight, particularly preferably 0.1 to 5 parts by weight, based on 100 parts by weight of the active hydrogen compound (excluding water). In the present invention, water is not included in the active hydrogen compound.
[0036]
In the present invention, a catalyst is used when the active hydrogen compound and the polyisocyanate compound are reacted. As the catalyst, a metal compound catalyst such as an organotin compound that promotes a reaction between an active hydrogen-containing functional group and an isocyanate group, an amine catalyst such as triethylenediamine, and the like can be used. A multimerization catalyst for reacting isocyanate groups such as carboxylic acid metal salts can also be used depending on the purpose.
[0037]
In addition, foam stabilizers are often used to form good bubbles. Examples of the foam stabilizer include a silicone foam stabilizer and a fluorine-containing compound foam stabilizer. In addition, examples of a compounding agent that can be optionally used include a filler, a stabilizer, a colorant, and a flame retardant.
[0038]
Using these raw materials, rigid polyurethane foam, urethane-modified polyisocyanate foam, and other rigid foamed synthetic resins can be obtained. The present invention is particularly useful in the production of rigid polyurethane foams and urethane-modified polyisocyanurate foams, which have conventionally been used in fields where a large amount of CFC-based foaming agents and HCFC-based foaming agents are used. Among them, it is particularly useful in the production of rigid polyurethane foam that is a heat insulating material for low thermal conductivity.
[0039]
【Example】
  EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples. Examples 1 to 3 are production examples of polyester polyol (X). “EO amount” and “PO amount” indicate oxyethylene group content and oxypropylene group content, respectively. “Part” is “part by weight”.
  Hard foam synthetic resin manufacturingExamples to Examples 4-6 and 10,Reference examples 7 to 9 for the production of hard foam synthetic resinThe comparative example of rigid foam synthetic resin manufacture is shown in Examples 11-16.
[0040]
[Example 1]
After introducing 722 parts of 1,4-butanediol, 1187 parts of phthalic anhydride and 3 parts of caustic potash into a 5 L autoclave and replacing with nitrogen, 341 parts of propylene oxide was successively introduced over 4 hours while stirring at 110 ° C. After completion of the reaction, 750 parts of ethylene oxide was sequentially introduced at 120 ° C. over 2 hours. After completion of the reaction, the polyester polyol A was produced by performing depressurization with heating at 120 ° C. and 0.1 mmHg for 30 minutes. The reaction product of 1,4-butanediol and phthalic anhydride was confirmed to be a polyester polyol in which propylene oxide and then ethylene oxide were reacted (hydroxyl value 300 mgKOH / g, phthalic acid residue 44% by weight, 1,4 -Content of unit (Y) based on butanediol of 20 wt%, PO amount of 11 wt%, EO amount of 25 wt%).
[0041]
[Example 2]
After introducing 722 parts of 1,4-butanediol, 1187 parts of phthalic anhydride and 3 parts of caustic potash into a 5 L autoclave and replacing with nitrogen, 1091 parts of propylene oxide was successively introduced over 6 hours while stirring at 110 ° C. A polyester polyol B was produced by heating and degassing at 110 ° C. and 0.1 mmHg for 30 minutes. The reaction product of 1,4-butanediol and phthalic anhydride was confirmed to be a polyester polyol in which propylene oxide was reacted (hydroxyl value 300 mgKOH / g, phthalic acid residue 44% by weight, 1,4-butanediol. Based on the unit (Y) content 20 wt%, PO amount 36 wt%).
[0042]
[Example 3]
In a 5 L autoclave, 937 parts of 1,6-hexanediol, 1175 parts of phthalic anhydride and 3 parts of caustic potash were charged and replaced with nitrogen, and then 900 parts of ethylene oxide was successively introduced over 4 hours while maintaining at 120 ° C. After completion of the reaction, the polyester polyol C was produced by depressurizing with heating at 120 ° C. and 0.1 mmHg for 30 minutes. The reaction product of 1,6-hexanediol and phthalic anhydride was confirmed to be a polyester polyol in which propylene oxide and then ethylene oxide were reacted (hydroxyl value 300 mgKOH / g, phthalic acid residue 43% by weight, 1,6 -Content of unit (Y) based on hexanediol 27 wt%, EO amount 30 wt%).
[0043]
[Examples 4 to 16]
For 100 parts of a mixture of polyols A to J shown in Tables 1 and 2, 2 parts of a silicone foam stabilizer (Nihon Unicar, L-5420), an amine catalyst N, N-dimethylcyclohexylamine (Tosoh Corporation, TOYOCAT-DMCH) parts shown in Tables 1 and 2, and types and parts of foaming agents shown in Tables 1 and 2 were weighed into a glass pressure vessel. Next, it was confirmed that this glass pressure vessel was mixed by a shaker for 30 minutes and became uniform. Hereinafter, this mixed solution is referred to as a polyol system. The state of the polyol system and the storage stability at 25 ° C. (the number of days until the components of the polyol system were separated) were evaluated. The results are shown in Tables 1-2.
[0044]
As the polyisocyanate compound, Millionate MR-200 (polymethylene polyphenylene polyisocyanate) manufactured by Nippon Polyurethane Industry Co., Ltd. is used, which is stirred and mixed with a polyol system at an isocyanate index = 115, and is made of aluminum having a length of 400 × width 400 × thickness 50 mm. The product was put into a mold and foamed to obtain a foam. The polyol system and the polyisocyanate compound were mixed after adjusting to a temperature of 12 ° C. A sample of a predetermined size was cut out from the obtained foam, and the density (unit: kg / m)^Three ) And thermal conductivity (unit: cal / m · hr · ° C.). The results are shown in Tables 1-2.
[0045]
Polyols D to J are as follows.
Polyol D: Polyester polyol obtained by reacting phthalic anhydride with diethylene glycol (hydroxyl value 300 mgKOH / g).
Polyol E: Polyester polyol obtained by reacting phthalic anhydride with 1,4-butanediol (hydroxyl value: 300 mgKOH / g).
Polyol F: A polyether polyol (hydroxyl value 350 mgKOH / g) obtained by addition polymerization of propylene oxide using tolylenediamine as an initiator.
[0046]
Polyol G: A polyether polyol obtained by addition polymerization of propylene oxide using bisphenol A as an initiator and then addition polymerization of ethylene oxide (hydroxyl value 250 mg KOH / g, EO amount 40% by weight).
Polyol H: A polyether polyol (hydroxyl value 420 mgKOH / g) obtained by addition polymerization of propylene oxide using a mixture of sucrose and glycerin as an initiator.
Polyol I: A polyether polyol (hydroxyl value 500 mgKOH / g, EO amount 5% by weight) obtained by addition polymerization of propylene oxide followed by addition polymerization of ethylene oxide using a mixture of sucrose and monoethanolamine as an initiator.
Polyol J: Polyether polyol J (hydroxyl value 550 mgKOH / g) obtained by addition polymerization of propylene oxide using monoethanolamine as an initiator.
[0047]
The blowing agents used were blowing agent a: cyclopentane, blowing agent b: HFC-245fa, blowing agent c: HFC-134a, and water.
[0048]
[Table 1]

[0049]
[Table 2]

[0050]
As can be seen from Examples 4 to 10, when a predetermined amount of polyester polyol (X) is used, a rigid urethane foam with low thermal conductivity is obtained, and the polyol system is transparent and excellent in storage stability.
[0051]
Further, as can be seen from Examples 11 to 16, when the polyester polyol (X) is used in an amount other than the predetermined amount, the thermal conductivity becomes high and the heat insulation performance is inferior, or the polyol system becomes milky and the storage stability is inferior.
[0052]
【The invention's effect】
Without using CFC or HCFC as a foaming agent, it is possible to produce a hard foamed synthetic resin with excellent heat insulation. The polyol system of the present invention is excellent in storage stability despite using a low-boiling hydrocarbon such as cyclopentane having high hydrophobicity or a hydrofluorocarbon such as HFC-245fa as a blowing agent.

Claims (3)

An active hydrogen compound and a polyisocyanate compound having an active hydrogen-containing functional group capable of reacting with two or more isocyanate groups, in the method are reacted in the presence of a blowing agent and a catalyst to produce a rigid foamed synthetic resin, an active hydrogen compound rigid foamed synthetic but which is characterized in that a mixture of the polyester polyol (X) 10 to 50 wt% and a polyether polyol 90-50% by weight of the following, and foaming agent is hydrocarbons having a carbon number of 4-6 Manufacturing method of resin.
Polyester polyol (X): aromatic polycarboxylic acid or derivative thereof and HOR ¹ OH (R ¹ is a polymethylene group having 3 or more carbon atoms or one or more hydrogen atoms of the group is substituted with an alkyl group having 1 to 5 carbon atoms. A polyester polyol obtained by reacting a diol (y) represented by a group represented by the following formula, followed by addition polymerization of an alkylene oxide , represented by a residue of an aromatic polycarboxylic acid, -R ¹ O-. A unit other than the unit (Y) and the unit (Y), wherein -R ² O- (R ² is a dimethylene group, or one or more hydrogen atoms of the group is an alkyl group having 1 to 5 carbon atoms. A polyester polyol having a unit (Z) represented by (substituted group). The manufacturing method of Claim 1 which uses water together as a foaming agent. The production method according to claim 1 or 2, wherein the hydrocarbon having 4 to 6 carbon atoms is cyclopentane.