JP2001329041A - Production method of rigid foamed synthetic resin - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a production method of an open cell rigid foamed synthetic resin of which raw materials has an excellent storage stability of and which has an excellent dimensional stability without generating sink-marks even if a large quantities of water is used as a foaming agent. SOLUTION: The production method of the rigid foamed synthetic resin comprises reacting (A) 25-60 mass% of a polyethyer polyol having an average hydroxyl group value of 300-600 mg KOH/g which is made by adding ethylene oxide or the ethylene oxide and an alkylene oxide of >=3C to sorbitol of an initiator, and contains contents of >=30 mass% of a construction unit based on the ethylene oxide, (B) 40-75 mass% of a polyol containing 10-55 mass% of the polyether polyol using a cyclic amine as an initiator, the polyol having an average hydroxyl group number of <=4 and the average hydroxyl group value of 200-600 mg KOH/g, and (C) a hydroxyl compound mixture containing 0-25 mass% of a polyether monool having the average hydroxyl group value of 20-700 mg KOH/g, the mixture being made by adding ethylene, propylene or both to an initiator, using the water as the foaming agent in the presence of a foam stabilizer and a catalyst.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for producing a rigid foamed synthetic resin such as a rigid polyurethane foam,
In particular, it relates to the production of rigid foam synthetic resins characterized by the use of specific blowing agents.

[0002]

2. Description of the Related Art It is widely practiced to produce a rigid foamed synthetic resin by reacting a hydroxyl compound and a polyisocyanate compound in the presence of a catalyst or the like. As the hydroxyl compound, a polyhydroxy compound is mainly used. Examples of the obtained rigid foamed synthetic resin include rigid urethane foam and rigid polyisocyanurate foam. The state of the cells of the hard foam synthetic resin includes closed cells and open cells. The closed-cell foam has closed cells, each of which is closed, and can be filled with a blowing agent having a low thermal conductivity such as halogenated hydrocarbons, and has excellent heat insulating performance. In the open-cell foam, individual cells are connected and have air permeability. For this reason, the open-cell foam has low heat insulating performance but is excellent in dimensional stability under severe temperature conditions. Although these foams are properly used depending on the application, closed-cell foams are generally used.

[0003] On the other hand, various compounds are known as a foaming agent for producing a foamed synthetic resin, and HCFC-141b, which is a kind of chlorinated fluorinated hydrocarbon, is mainly used. Also, various proposals have been made in which other fluorinated hydrocarbons having a relatively low boiling point can be used as a blowing agent. However, except for the above-mentioned HCFC-141b, it has not yet been widely used. It is considered that the use of halogenated hydrocarbons used as a blowing agent causes ozone depletion because a part of the hydrocarbons leak into the atmosphere. Thus, there is an increasing need for such blowing agents to reduce their use or to replace them with other blowing agents. As a method for solving the above problem, it has been proposed to use a large amount of water as a blowing agent. Water is a primary blowing agent in flexible polyurethane foams and an important secondary blowing agent in rigid polyurethane foams. However, HCFC-141b used as a main foaming agent for rigid polyurethane foams
Was difficult to use at a high enough ratio that could be replaced.

A foamed synthetic resin using a large amount of water has a problem that the synthetic resin becomes brittle because the ratio of urea bonds generated by the reaction between water and isocyanate increases. Further, even if the foamed synthetic resin using a large amount of water has good initial performance, there is a problem that the foamed synthetic resin is gradually deformed when left at normal temperature for a long time.
In order to use water as a blowing agent that replaces the conventional fluorinated hydrocarbon-based blowing agents, it is necessary to develop a technology that solves these problems. In order to cope with poor dimensional stability of a foam due to a formulation using a large amount of water as a foaming agent, it is conceivable to use an open-cell foam synthetic resin in applications where heat insulation performance is not important.

[0005] As a method for producing a rigid foam synthetic resin having open cells, a short-chain polyol is mixed with a long-chain polyol, a special silicone foam stabilizer is used, or a hydrophobic hydroxyl compound is mixed. There is a way to do that. However, the mixed raw material becomes cloudy and easy to separate, making it impossible to store the prepared raw material for a long time. Also, if only the water is used as the foaming agent and the weight is reduced, the foaming speed cannot keep up with the resination speed and the rigid foam synthetic resin is unstable. And it is difficult to obtain a good hard foamed synthetic resin. If a large amount of a catalyst or a foam stabilizer is used to prevent this, closed cells are formed and it is difficult to stably obtain an open-cell foam synthetic resin. Generalization of open-cell synthetic resin also requires means for solving these problems.

[0006]

DISCLOSURE OF THE INVENTION The present invention has excellent storage stability of a raw material without using a special silicone foam stabilizer or a hydrophobic hydroxyl compound in the raw material liquid, and has a high storage stability at the time of foaming. Excellent in fluidity, hard foam synthetic resin does not collapse even when a large amount of water is used as a foaming agent, and the obtained rigid foam synthetic resin has excellent dimensional stability and strength, and easily obtains an open-cell foam. It is an object of the present invention to provide a method for producing a rigid foam synthetic resin that can be used.

[0007]

Means for Solving the Problems The present invention has been made to solve the problems described above, and has found that the above problems can be solved by using a specific hydroxyl compound mixture and using water as a foaming agent. Thus, the present invention has been completed. That is, the present invention relates to a method for producing a rigid foamed synthetic resin by reacting a hydroxyl compound with a polyisocyanate compound in the presence of a foaming agent, a foam stabilizer and a catalyst. Polyether polyol 25 which is produced by adding ethylene oxide or ethylene oxide and an alkylene oxide having 3 or more carbon atoms to sorbitol, the content of structural units based on ethylene oxide is 30% by mass or more, and the average hydroxyl value is 300 to 600 mgKOH / g. (B) a polyol having an average number of hydroxyl groups of 4 or less and an average hydroxyl value of 200 to 600 mgKOH / g, containing 10 to 55% by mass of a polyether polyol having a cyclic amine as an initiator.
0-75% by mass, and (C) produced by adding ethylene oxide, propylene oxide or both to the initiator, and having an average hydroxyl value of 20-700 mgKOH / g.
Using a hydroxyl compound mixture containing 0 to 25% by mass of a polyether monool of the formula (1), and using water as a foaming agent.

In the present invention, in the method for producing a rigid foamed synthetic resin, water is used as a foaming agent in an amount of 6 to 14 parts by mass based on 100 parts by mass of the total of (A), (B) and (C). Provided is a method for producing a rigid foam synthetic resin. Further, the present invention provides the method for producing a rigid foamed synthetic resin, wherein the polyol (B) comprises 10 to 55% by mass of a polyether polyol having a cyclic amine as an initiator, and water, ethylene glycol, diethylene glycol, propylene glycol, Propylene glycol, glycerin, trimethylolpropane, diglycerin, pentaerythritol, monoethanolamine, diethanolamine, triethanolamine, ethylenediamine, diethylenetriamine, tolylenediamine and at least one selected from Mannich reaction products of phenols with alkanolamines and aldehydes Polyether polyols 45 to 45 obtained by reacting an alkylene oxide with one kind of initiator
Disclosed is a method for producing a rigid foam synthetic resin which is a polyol consisting of 90% by mass.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention is characterized in that polyols (A), polyols (B) and polyether monools (C) are used in specific proportions as hydroxyl compounds. The polyol (A) is produced by adding ethylene oxide or ethylene oxide and an alkylene oxide having 3 or more carbon atoms to sorbitol as an initiator. The content of the structural unit based on ethylene oxide is 30% by mass or more, and the average hydroxyl value is 300.
~ 600 mg KOH / g polyol. Carbon number 3
Examples of the above alkylene oxide include propylene oxide and butylene oxide, and propylene oxide is preferable. The content ratio of the structural unit based on ethylene oxide in the polyol (A) is 30% by mass or more, and preferably 40% by mass or more. When the content ratio of the structural unit based on ethylene oxide is less than 30% by mass, the obtained rigid foamed synthetic resin becomes brittle. The upper limit of the content of the structural unit based on ethylene oxide is not particularly limited, but is preferably 85% by mass or less, and particularly preferably 75% by mass or less. The polyol may be a mixture of different hydroxyl values. In the present invention, the content ratio of the structural unit based on ethylene oxide indicates the mass% of the structural unit based on ethylene oxide with respect to the total mass of the polyol including the initiator. The average hydroxyl value of the polyol (A) is from 300 to 600 mgKOH / g, preferably from 350 to 550 mgKOH / g.
Particularly preferred is -500 mg KOH / g. When the average hydroxyl value exceeds 600 mgKOH / g, the viscosity becomes too high, and the handleability is poor, and the mixing property is poor.
On the other hand, if it is less than 300 mgKOH / g, the resin becomes soft.

The polyol (B) is a polyol having an average number of hydroxyl groups of 4 or less and an average hydroxyl value of 200 to 600 mgKOH / g and containing 10 to 55% by mass of a polyether polyol having a cyclic amine as an initiator. is there. The cyclic amine of the initiator used for producing the polyether polyol obtained by using the cyclic amine in the polyol (B) as an initiator is a compound having a nitrogen atom in the ring, and N- (2-amino Ethyl) piperazine, piperazine, N, N'-bis (2-aminopropyl) piperazine, hydantoin, N- (2-hydroxyethyl) piperazine and 1,3-bis (hydrazinocarboethyl) -5-isopropylhydantoin Preferred are mentioned. Examples of the alkylene oxide to be added to the cyclic amine of the initiator include ethylene oxide, propylene oxide, butylene oxide and the like. Of these, ethylene oxide, propylene oxide,
Or a combination of both is preferred. The polyether polyol obtained using a cyclic amine as an initiator has a hydroxyl value of 1
50-600 mgKOH / g is preferable, and 200-50
0 mgKOH / g is preferred, and 250-450 mgKO
H / g is particularly preferred. In the polyol (B),
The content ratio of the polyether polyol having a cyclic amine as the initiator is 10 to 55% by mass, preferably 15 to 50% by mass, and particularly preferably 20 to 45% by mass. When the content of the polyol having the cyclic amine as the initiator exceeds 55% by mass, the hard foamed synthetic resin tends to shrink.
If the amount is less than 0% by mass, the cells of the hard foamed synthetic resin become rough.

As the polyol other than the polyol having a cyclic amine as the initiator in the polyol (B), polyether polyols, polyester polyols, hydroxyl-containing diene polymers, compounds having two or more phenolic hydroxyl groups, and the like can be used. As the polyether polyol, a cyclic ether as an initiator other than the cyclic amine,
Particularly, a polyether polyol obtained by adding propylene oxide, ethylene oxide, or butylene oxide is preferable, and a polyether polyol obtained by adding propylene oxide, ethylene oxide, or both is particularly preferable.

As the initiator other than the cyclic amine, the number of functional groups is preferably 5 or less, and preferable examples thereof include a polyhydroxyl compound and a polyamine compound. Specific examples of these initiators include water, ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, glycerin, trimethylolpropane, diglycerin, pentaerythritol, monoethanolamine, diethanolamine, triethanolamine, ethylenediamine, diethylenetriamine, Preferred examples include tolylenediamine and Mannich reaction products of phenols, alkanolamines and aldehydes. Further, a polyol composition in which fine particles of a vinyl polymer are dispersed in a polyol mainly containing a polyether polyol called a polymer polyol or a graft polyol can also be used. Polyester polyols include polyhydric alcohols, polycarboxylic acid condensation-based polyols and cyclic ester ring-opening polymer type polyols, and polyhydric alcohols include ethylene glycol, propylene glycol, diethylene glycol,
Examples include dipropylene glycol, glycerin, trimethylolpropane, pentaerythritol, diethanolamine, and triethanolamine.

As the compound having two or more phenolic hydroxyl groups, a non-reactive compound such as a resol-type initial condensate in which a phenol is condensed and bound with an excess formaldehyde in the presence of an alkali catalyst is used. There are benzylic ether type precondensates reacted in an aqueous system, and novolak type precondensates obtained by reacting excess phenols with formaldehydes in the presence of an acid catalyst. The molecular weight of these precondensates is preferably from 200 to 10,000. Here, the phenols mean those in which one or more carbon atoms of a skeleton forming a benzene ring are directly bonded to a hydroxyl group, and include those having another substituent in the same structure. Representative phenols include phenol, cresol, bisphenol A, resorcinol and the like. The formaldehyde is not particularly limited, but formalin and paraformaldehyde are preferred. As the polyol other than the polyol having a cyclic amine as the initiator in the polyol (B), a polyether polyol is preferable. The polyol (B) is a polyol obtained by separately preparing a polyether polyol obtained using a cyclic amine as an initiator and a polyol obtained using another initiator, and mixing those polyols. Or a polyol obtained by using a mixed initiator obtained by mixing a cyclic amine initiator and another initiator.

The average number of hydroxyl groups of the polyol (B) is 4 or less, preferably 2 to 4. The average hydroxyl value of the polyol (B) is from 200 to 600 mgKOH / g, preferably from 250 to 550 mgKOH / g.
Particularly preferred is -500 mg KOH / g. When the average hydroxyl value of the polyol (B) exceeds 600 mgKOH / g, the viscosity becomes too high and handling becomes difficult.
If it is less than 200 mgKOH / g, the resin becomes too soft. The content ratio of the polyol (A) is 25 to 60% by mass based on the total amount of the polyol (A), the polyol (B), and the polyether monol (C).
0-60 mass% is preferable, and 35-55 mass% is especially preferable. The content ratio of the polyol (B) is 40 to 75% by mass based on the total amount of the polyol (A), the polyol (B), and the polyether monol (C).
It is preferably from 0 to 70% by mass, and particularly preferably from 45 to 65% by mass.

The polyether monol (C) is produced by adding ethylene oxide, propylene oxide or both to an initiator and has an average hydroxyl value of 20 to 70.
0 mgKOH / g polyether monol. Examples of the initiator used for the production of the polyether monol (C) include monoalcohols such as methanol, ethanol, propanol, butanol, hexanol, octanol, dodecanol and stearyl alcohol, and alkylphenols such as octylphenol, nonylphenol and decaphenol. No. The carbon number of the monoalcohol is preferably 1 to 22, particularly preferably 8 to 22, and the alkylphenol has a carbon number of 10 to 18.
Is preferred. The average hydroxyl value of the polyether monol (C) is from 20 to 700 mgKOH / g,
500 mgKOH / g is preferred, and 40 to 200 mgK
OH / g is particularly preferred. If the average hydroxyl value of the polyether monol (C) exceeds 700 mgKOH / g, the resin cells are likely to be rough, and if it is less than 20 mgKOH / g, the resin becomes soft.

The content ratio of the polyether monool (C) is from 0 to 25% by mass, preferably from 0 to 25% by mass, based on the total amount of the polyol (A), the polyol (B) and the polyether monool (C). 20% by mass. In the present invention, an active hydrogen compound other than the polyols (A) and (B) and the polyether monol (C) can be used in combination. Examples of the active hydrogen compound include an aminated polyol. In the present invention, water is used as a foaming agent in an amount of 6 to 14 parts by mass per 100 parts by mass of the hydroxyl compound. It is particularly preferable to use 6 to 12% by mass. Further, in the present invention, water can be used as a single foaming agent in a formulation, but a compound of a low boiling halogenated hydrocarbon can be used in combination as a foaming agent according to the purpose.

The low-boiling halogenated hydrocarbon is not particularly limited, but may be 1,1-dichloro-1-fluoroethane (HCFC-141b), chlorodifluoromethane (HCFC-22), 1,1,1,2. -Tetrafluoroethane (HFC-134a), 1-chloro-1,1-difluoroethane (HCFC-142b), 1,1-dichloro-2,2,3,3,3-pentafluoropropane (HCFC-225ca), 1,3-dichloro-1,
1,2,2,3-pentafluoropropane (HCFC-
225cb), pentafluoroethane (HFC-12
5), 1,1,2-trifluoroethane (HFC-14
3), 1,1,1-trifluoroethane (HFC-14
3a), 1,1,1,2,3,3-hexafluoropropane (HFC-236ea) and its isomers,
1,2,2,3-pentafluoropropane (HFC-2
45ca) and isomers thereof, 1,1,1,4,4,4
-Hexafluorobutane (HFC-356mff),
1,1,1,3,3-pentafluoropropane (HFC
-245fa), 1,1,1,3,3-pentafluorobutane (HFC-365mff) and the like. In addition, a low boiling halogenated hydrocarbon containing no fluorine such as methylene chloride can be used in combination as a blowing agent. Although it is not preferable to use halogenated hydrocarbons as a blowing agent in view of environmental issues, the technology of the present invention increases the number of parts of water to be used without reducing the performance of the foamed synthetic resin. Can be greatly reduced. When a low-boiling halogenated hydrocarbon is used in combination as the blowing agent, the usage ratio of the low-boiling halogenated hydrocarbon is suitably from 0 to 500 parts by mass with respect to 100 parts by mass of water.

Further, low boiling hydrocarbons such as butane, pentane and hexane, and inert gases such as air and nitrogen can also be used together as the foaming agent. When a low-boiling hydrocarbon or an inert gas is used in combination as the blowing agent, the proportion of the low-boiling hydrocarbon or the inert gas used is 0 to 100 parts by mass of water.
500 parts by weight are suitable. In the present invention, even when water and alternative chlorofluorocarbon are used together as a foaming agent, the number of parts of water to be used can be increased and the amount of alternative fluorocarbon used can be reduced. Examples of the polyisocyanate compound include aromatic, alicyclic, and aliphatic polyisocyanates having two or more isocyanate groups, and modified polyisocyanates obtained by modifying them. One type of polyisocyanate compound may be used, or a mixture of two or more types may be used.

Specifically, for example, tolylene diisocyanate, diphenylmethane diisocyanate, polymethylene polyphenyl isocyanate (commonly known as Crude MD)
I), polyisocyanates such as xylylene diisocyanate, isophorone diisocyanate and hexamethylene diisocyanate, and urethane-modified, nurate-modified, urea-modified and carbodiimide-modified products thereof.
The polyisocyanate compound is expressed as 100 times the number of isocyanate groups with respect to the total number of active hydrogens of the polyol, polyether monol and other active hydrogen compounds (usually, the value expressed by 100 times is referred to as isocyanate index). 300, preferably 80-150,
Particularly preferably, it is desirable to use it in the range of 85 to 120.

When reacting a hydroxyl compound with a polyisocyanate compound, it is usually necessary to use a catalyst. Examples of the catalyst include a metal compound catalyst such as an organotin compound that promotes the reaction between an active hydrogen-containing group and an isocyanate group, and a tertiary amine catalyst such as triethylenediamine. In addition, a multimerization catalyst for reacting isocyanate groups with each other, such as a metal carboxylate, is used depending on the purpose.
The amount of the catalyst used may be appropriately selected, but is preferably 0.1 to 10 parts by mass with respect to 100 parts by mass of the hydroxyl compound mixture.

In the present invention, a foam stabilizer for forming good air bubbles is also used. Examples of the foam stabilizer include a silicone foam stabilizer and the like. The amount of the foam stabilizer may be appropriately selected, but is preferably 0.1 to 10 parts by mass with respect to 100 parts by mass of the hydroxyl compound mixture. In addition, as a compounding agent which can be optionally used as a raw material, for example, there are a filler, a stabilizer, a coloring agent, a flame retardant and the like. According to the present invention, even if a large amount of water is used as a foaming agent, the hard foamed synthetic resin does not collapse, and a low-solubility special silicone foam stabilizer and without using a hydrophobic hydroxyl compound,
It has excellent raw material storage stability and can easily obtain an open-cell synthetic resin foam. The foamed synthetic resin produced by the present invention has open cells, and preferably has a closed cell ratio of 50% or less. ADVANTAGE OF THE INVENTION According to this invention, the rigid foam synthetic resin of the open cell of the closed cell rate of 0-50% can be easily prepared according to the objective. When the closed cell ratio is less than 50%, the characteristics of the open-cell rigid foam synthetic resin, such as improvement of dimensional stability and reduction of the foaming pressure, can be further brought out.

[0022]

EXAMPLES Hereinafter, the present invention will be described specifically with reference to examples, but the present invention is not limited to these examples. In Examples and Comparative Examples, parts mean parts by mass.

Examples 1 to 5 A foaming agent, a general-purpose silicone foam stabilizer and an amine catalyst (necessary amount for a gel time of about 50 seconds) were used for the combination of polyol and polyether monol (100 parts in total) shown in Table 1. ) Were mixed. This mixture and crude MDI were mixed at an isocyanate group: active hydrogen group = 1.1: 1 (isocyanate index 110) at a liquid temperature of 20 ° C.
A 5 mm aluminum mold was heated to 40 ° C., and the mixture was charged and reacted. The density (kg / m ³ ) and compressive strength (MPa) of the obtained polyurethane foam ), Closed cell ratio (%), dimensional stability at 70 ° C. and 95% relative humidity, fluidity, and surface peeling during demolding were evaluated. The results are shown in Table 1.

[0024]

[Table 1]

Note: The abbreviations of polyol and polyether monol in Table 1 indicate the following. A1: hydroxyl value 500 mg KOH / obtained by subjecting propylene oxide to addition reaction using sorbitol as an initiator
g of polyether polyol. A2: Polyether polyol having a hydroxyl value of 450 mgKOH / g and a structural unit of 10% by mass based on ethylene oxide obtained by subjecting propylene oxide to an addition reaction using sorbitol as an initiator and then adding ethylene oxide to the reaction. A3: Polyether polyol having a hydroxyl value of 450 mgKOH / g and a constitutional unit of 46% by mass based on ethylene oxide obtained by subjecting sorbitol to addition reaction with propylene oxide and then ethylene oxide.

B1: Addition reaction of propylene oxide to pentaerythritol, and then addition reaction of ethylene oxide. The number of hydroxyl groups was 4, and the hydroxyl value was 410 mgK.
OH / g polyether polyol. B2: A polyether polyol having 2 hydroxyl groups and a hydroxyl value of 490 mgKOH / g obtained by subjecting dipropylene glycol to an addition reaction of propylene oxide and then to an ethylene oxide. B3: Polyether polyol having 3 hydroxyl groups and a hydroxyl value of 300 mgKOH / g obtained by adding propylene oxide to N- (2-aminoethyl) piperazine. B4: Polyether polyol having a hydroxyl value of 35 mgKOH / mg obtained by subjecting glycerin to an addition reaction of propylene oxide and then to an ethylene oxide. C1: 1 mole of ethylene oxide per mole of nonylphenol
Polyether monool (hydroxyl value 85
mgKOH / g)

Note) The additives in Table 1 are as follows. Flame retardant: tris (β-chloropropyl) phosphate Foam stabilizer: Silicone foam stabilizer, manufactured by Nippon Unicar, SZ-
1677 catalyst: N, N, N ', N'-tetramethylhexamethylenediamine, manufactured by Tosoh Corporation, MR
This was performed by the following method. Fluidity evaluation test The fluidity was measured by mixing a mixture of the raw materials of the examples at 20 ° C. at a temperature of 40 ° C. and vertically setting an aluminum mold of 40 cm × 40 cm × 5 cm. Is expressed as the urethane foam weight (panel-free weight) of a 40 cm × 40 cm × 5 cm portion after overflowing, and it was judged that the lighter the liquid, the better the flowability. Brittleness evaluation test A 10% increase in panel-free weight in the fluidity evaluation was performed in the same 40 cm × 40 cm × 5 cm mold at a mold temperature of 4
It was packed at 0 ° C., and was judged by the degree of peeling of the surface of the polyurethane molded product after demolding for 10 minutes. The absence of delamination was considered to be free of brittleness.

Comparative Examples 1 to 4 In the same manner as in the Examples, the combination of the polyol and the polyether monool (total 100 parts) shown in Table 2
A general-purpose silicone foam stabilizer and an amine catalyst (required for a gel time of about 50 seconds) were mixed. This mixed solution and crude MDI were mixed with an isocyanate group: active hydrogen group = 1.
The mixture was mixed at a liquid temperature of 20 ° C. at a ratio of 1: 1 (isocyanate index 110), and a 40 × 40 × 5 cm aluminum mold was mixed
The mixture was charged to 0 ° C. and reacted. The density (kg / m ³ ) and compressive strength (MPa) of the obtained polyurethane foam ), Closed cell ratio (%), dimensional stability at 70 ° C. and 95% relative humidity, fluidity, and surface peeling during demolding were evaluated. Table 2 shows the results.

[0029]

[Table 2]

[0030]

EFFECT OF THE INVENTION According to the present invention, there is no separation during storage of the polyol formulation, good fluidity at the time of foaming, and no brittleness of the obtained rigid foamed synthetic resin, and the open cells having good dimensional stability have good dimensional stability. A foam synthetic resin can be manufactured.

Continuing from the front page (72) Inventor Tadanobu Kuroki 3-474-2 Tsukakoshi, Saiwai-ku, Kawasaki-shi, Kanagawa Prefecture Asahi Glass Co., Ltd. (72) Inventor Hiromitsu Takeyasu 3-474-2 Tsukakoshi, Saiwai-ku, Kawasaki-shi, Kanagawa Prefecture (72) Inventor Hiromichi Hotta 2-8-8 Yaesu, Chuo-ku, Tokyo Ohashi Yaesu Building F-term in Asahi Glass Urethane Co., Ltd. 4J034 BA03 BA07 CE01 DB03 DB05 DG01 DG02 DG03 DG04 DG09 DG14 DG22 DG23 DG25 HA01 HA06 HA07 HB06 HB07 HC01 HC02 HC03 HC11 HC12 HC22 HC25 HC34 HC35 HC46 HC52 HC61 HC63 HC64 HC65 HC66 HC67 HC71 HC73 LA08 NA01 NA03 QA02 QB01 QB16 QC01

Claims (3)

[Claims] 1. A method for producing a rigid foamed synthetic resin by reacting a hydroxyl compound with a polyisocyanate compound in the presence of a foaming agent, a foam stabilizer and a catalyst, wherein (A) sorbitol as an initiator Is produced by adding ethylene oxide or an ethylene oxide and an alkylene oxide having 3 or more carbon atoms, the content of the constituent units based on ethylene oxide is 30% by mass or more, and the average hydroxyl value is 300 to 600.
25-60 mass% of polyether polyol of mgKOH / g, (B) average hydroxyl number is 4 or less and average hydroxyl value is 20
0 to 600 mgKOH / g of a polyether polyol having a cyclic amine as an initiator.
40 to 75% by mass of a polyol containing 55% by mass, and (C) 0 to 25% by mass of a polyether monool produced by adding ethylene oxide, propylene oxide or both to an initiator and having an average hydroxyl value of 20 to 700 mgKOH / g. % Of a hydroxyl compound mixture containing water and water as a blowing agent. 2. The method for producing a rigid foam synthetic resin according to claim 1, wherein 6 to 14 parts by mass of water is used as a foaming agent based on 100 parts by mass of the total of (A), (B) and (C). 3. The polyol (B) comprises 10 to 55% by mass of a polyether polyol having a cyclic amine as an initiator;
Water, ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, glycerin, trimethylolpropane, diglycerin, pentaerythritol, monoethanolamine, diethanolamine, triethanolamine, ethylenediamine, diethylenetriamine, tolylenediamine and phenols and alkanolamines The rigid foam according to claim 1 or 2, which is a polyol comprising 45 to 90% by mass of a polyether polyol obtained by reacting an alkylene oxide with at least one initiator selected from a Mannich reaction product with an aldehyde. Manufacturing method of synthetic resin.