JP2012107214A - Method for producing rigid foamed synthetic resin - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing a rigid foamed synthetic resin, which can obtain the satisfactory storage stability of a polyol system liquid, and further can produce more lightweight rigid foam while suppressing shrinkage deformation.SOLUTION: A polyol composition (P) and a polyisocyanate compound (Y) are reacted in the presence of a foaming agent, a flame retardant, a foam stabilizer and a catalyst to produce a rigid foamed synthetic resin. The polyol composition (P) includes 10 to 60 mass% of polyether polyol (A) which is obtained by performing the ring-opening addition polymerization of alkylene oxide to an initiator (S1) having the number of functional groups satisfying 2 to 8, and which has a hydroxyl value of 10 to 100 mgKOH/g, and in which 20 to 95 mass% of the alkylene oxide is occupied by ethylene oxide, the terminal part is capped with the random chains of an oxyethylene group and an oxypropylene group, and the ratio of the random chains present at the terminal part is 10 to 100 mass% of the oxyalkylene chains.

Description

  The present invention relates to a method for producing a rigid foam synthetic resin.

It is widely used to react a polyol and a polyisocyanate compound in the presence of a foaming agent to produce a rigid foamed synthetic resin (hereinafter sometimes referred to as a rigid foam) such as a rigid polyurethane foam and a rigid polyisocyanurate foam. Has been done.
For example, in construction and building material applications, it is desired to reduce the weight in addition to heat insulation performance and flame retardancy. If foaming is performed using a large amount of a foaming agent, the weight can be reduced, but the foam tends to shrink due to insufficient cell strength.

In addition, low-boiling fluorine-containing compounds that have been used mainly as conventional blowing agents have the problem of promoting global warming when they are present in the atmosphere, so the use of fluorine-containing compounds using water as the blowing agent Techniques for reducing the amount have been proposed.
However, when a large amount of water is used as a foaming agent, it becomes difficult to dissolve components having low hydrophilicity among the raw materials. For this reason, there are problems of deterioration of storage stability and poor mixing of the polyol system liquid and the polyisocyanate liquid in a mixed liquid (hereinafter also referred to as a polyol system liquid) in which a polyol, a foaming agent, a catalyst, and the like are mixed. Prone to occur. When foamed, the size and distribution of foam bubbles are likely to be non-uniform, resulting in rough cells and the formation of many closed cells, which tends to cause shrinkage and collapse of the foam.
Therefore, particularly in the method of using water as the foaming agent, it is more difficult to reduce the weight of the rigid foam by increasing the amount of foaming agent used.

In manufacturing sites and the like, a spray method is often employed when producing a rigid foamed synthetic resin. The spray method is, for example, a polyol system liquid and a polyisocyanate compound are respectively pumped, reacted while sprayed from a spray gun to a wall surface to be constructed, and foamed on the wall surface, etc. It is a method to do. Since the spray method is often performed outdoors, the storage stability of the polyol system liquid is required.
In the following Patent Document 1, a polyol composition containing the following polyether polyols (I), (II), and (III) is used in a spray method in which water is mainly used as a blowing agent or only water is used. A method has been proposed. According to this method, even when a large amount of a foaming agent is used for weight reduction, the storage stability of the polyol system liquid is good, and the rigid foam obtained when foamed has good dimensional stability. ing.
Polyol (I): A polyether polyol having a hydroxyl value of 100 to 900 mgKOH / g, obtained by ring-opening addition polymerization of alkylene oxide to an initiator having 2 to 8 functional groups containing no nitrogen atom.
Polyol (II): a hydroxyl group having a hydroxyl value of 20 to 56 mgKOH / g, obtained by reacting an ethylene oxide with a ring-opening addition polymerization of an alkylene oxide other than ethylene oxide with an initiator having 2 to 8 functional groups containing no nitrogen atom A polyether polyol having an oxyethylene block chain content of 5 to 15% by mass.
Polyol (III): A polyether polyol having a hydroxyl value of 200 to 850 mgKOH / g, obtained by ring-opening addition polymerization of an alkylene oxide to an initiator having 3 to 5 functional groups containing a nitrogen atom.

JP 2010-168575 A

In the example of Patent Document 1, a rigid foam lightened to a density of 12.1 kg / m ³ by a cup foaming method can be successfully manufactured, and a rigid foam lightened to a density of 13.1 kg / m ³ by spray foaming. It was shown that it was able to be manufactured successfully.
The object of the present invention is to realize a rigid foam that is lighter than these examples. That is, an object of the present invention is to provide a method for producing a rigid foamed synthetic resin capable of producing a lighter rigid foam while suppressing shrinkage deformation while obtaining good storage stability of a polyol system liquid.

The present invention is the following [1] to [9].
[1] In a method for producing a rigid foam synthetic resin by reacting a polyol composition (P) and a polyisocyanate compound (Y) in the presence of a foaming agent, a flame retardant, a foam stabilizer and a catalyst, the polyol composition (P) is a polyol composition having an average number of hydroxyl groups of 2 to 8 and an average hydroxyl value of 100 to 700 mgKOH / g, comprising 10 to 60% by mass of the following polyol (A). Manufacturing method of resin.
Polyol (A): a polyether polyol having a hydroxyl value of 10 to 100 mgKOH / g, obtained by ring-opening addition polymerization of alkylene oxide to an initiator (S1) having 2 to 8 functional groups, 20 to 95% by mass is ethylene oxide, the terminal part is capped with a random chain of oxyethylene group and oxypropylene group, and the proportion of the random chain present in the terminal part is 10 to 100% by mass of the oxyalkylene chain A polyether polyol.

[2] The method for producing a rigid foam synthetic resin according to [1], wherein the polyol composition (P) contains 40 to 90% by mass of the following polyol (B).
Polyol (B): A polyether polyol having a hydroxyl value of 200 to 1,000 mgKOH / g, obtained by subjecting an initiator (S2) having 2 to 8 functional groups to ring-opening addition polymerization of only propylene oxide.
[3] The method for producing a hard foam synthetic resin according to [1] or [2], wherein the polyol composition (P) contains 3 to 40% by mass of the following polyol (C).
Polyol (C): A polyether having a hydroxyl value of 80 to 200 mgKOH / g, obtained by subjecting an initiator (S3) having 2 to 8 functional groups to ring-opening addition polymerization of propylene oxide and then ring-opening addition polymerization of ethylene oxide. Polyol.

[4] Any of [1] to [3], wherein the blowing agent contains water, and the amount of water used is 15 to 60 parts by mass with respect to 100 parts by mass of the polyol composition (P). Manufacturing method of hard foam synthetic resin.
[5] The method for producing a hard foamed synthetic resin according to any one of [1] to [4], wherein only water is used as the foaming agent.
[6] Manufacture of the hard foam synthetic resin in any one of [1]-[5] whose usage-amount of the said flame retardant is 10-100 mass parts with respect to 100 mass parts of a polyol composition (P). Method.
[7] The method for producing a hard foam synthetic resin according to any one of [1] to [6], wherein the polyisocyanate compound (Y) is used in an amount of 10 to 100 in terms of isocyanate index.
[8] The method for producing a hard foamed synthetic resin according to any one of [1] to [7], wherein the core density of the obtained hard foamed synthetic resin is 5 to 12 kg / m ³ .
[9] The method for producing a hard foam synthetic resin according to any one of [1] to [8], wherein the hard foam synthetic resin is produced by a spray method.

  According to the method for producing a rigid foamed synthetic resin of the present invention, a good storage stability of the polyol system liquid can be obtained, and a lighter rigid foamed synthetic resin can be produced while suppressing shrinkage deformation.

  The method for producing a rigid foam of the present invention is a method in which a polyol composition (P) and a polyisocyanate compound (Y) are reacted in the presence of a foaming agent, a flame retardant, a foam stabilizer and a catalyst.

[Polyol composition (P)]
The polyol composition (P) of the present invention is a polyol composition having an average hydroxyl number of 2 to 8 and an average hydroxyl value of 100 to 700 mgKOH / g. The average number of hydroxyl groups is an average value of the number of hydroxyl groups of all polyols contained, and the average hydroxyl value is an average value of the hydroxyl values of all polyols contained. The average number of hydroxyl groups is preferably 2-6, particularly preferably 2-4. The average hydroxyl value is more preferably from 150 to 700 mgKOH / g, particularly preferably from 200 to 650 mgKOH / g.
Moreover, a polyol composition (P) contains 10-60 mass% of polyols (A). A polyol composition (P) containing a polyol (A), a polyol composition (P) containing a polyol (A) and a polyol (B), or a polyol (A), a polyol (B) and a polyol (C). A polyol composition (P) is preferred. Other active hydrogen compounds (D) may be included as long as the physical properties are not impaired.

[Polyol (A)]
The polyol (A) is a polyether polyol having a hydroxyl value of 10 to 100 mgKOH / g, obtained by ring-opening addition polymerization of an alkylene oxide to an initiator (S1) having 2 to 8 functional groups.

  The number of functional groups of the initiator (S1) is 2-8. The number of functional groups is preferably 2 to 6, and particularly preferably 2 to 4. In the present invention, the number of functional groups of the initiator means the number of active hydrogen atoms of the initiator. When the number of functional groups of the initiator (S1) is at least the lower limit of the above range, the strength of the resulting rigid foam tends to be good, and when it is below the upper limit of the above range, the viscosity of the polyol (A) increases. However, it is easy to ensure the mixing property of the polyol composition (P) and the polyol system liquid.

As the initiator (S1), water, polyhydric alcohols, or amine compounds are used.
Specific examples of the polyhydric alcohols include ethylene glycol, propylene glycol, glycerin, trimethylolpropane, diethylene glycol, diglycerin, pentaerythritol, sorbitol, sucrose and the like.
Examples of amine compounds include aliphatic amines, alicyclic amines, and aromatic amines. Examples of the aliphatic amines include alkylamines such as ethylenediamine, hexamethylenediamine, and diethylenetriamine, and alkanolamines such as monoethanolamine, diethanolamine, and triethanolamine. Examples of the alicyclic amines include aminoethylpiperazine. Aromatic amines include diaminotoluene and Mannich reaction products. The Mannich reaction product is a reaction product of phenols, alkanolamines and aldehydes, and examples thereof include reaction products of nonylphenol, monoethanolamine and formaldehyde.
One type of initiator (S1) may be used, or two or more types may be used in combination.
Water or polyhydric alcohols are preferable in terms of excellent storage stability, and in particular, at least one selected from the group consisting of water, ethylene glycol, propylene glycol, glycerin, trimethylolpropane, diglycerin, pentaerythritol, sorbitol, and sucrose. Species are preferred.

As the alkylene oxide used for the production of the polyol (A), at least propylene oxide (hereinafter also referred to as PO) and ethylene oxide (hereinafter also referred to as EO) are used. Examples of other alkylene oxides include 1,2-epoxybutane, 2,3-epoxybutane, and styrene oxide. It is preferable that the alkylene oxide used for the production of the polyol (A) consists only of propylene oxide and ethylene oxide.
Of the alkylene oxide added to the initiator (S1), 20 to 95% by mass is ethylene oxide. 25-95 mass% is preferable, 30-90 mass% is more preferable, and 30-85 mass% is especially preferable. When the ratio of the ethylene oxide is not less than the lower limit of the above range, good storage stability of the polyol system liquid is easily obtained, and when it is not more than the upper limit of the above range, the activity of the polyol (A) does not become too high. . If the activity of the polyol is too high, a large number of closed cells are likely to be formed, resulting in foam shrinkage.

Of the oxyalkylene chain derived from the alkylene oxide added to the initiator (S1), the terminal portion is capped with a random chain of an oxyethylene group and an oxypropylene group. The ratio of the random chain present in the terminal portion is 10 to 100% by mass of the oxyalkylene chain. The proportion of the random chain is preferably 30 to 100% by mass, particularly preferably 50 to 100% by mass. When the ratio of the random chain is in the above range, the shrinkage of the rigid foam is easily prevented. When the proportion of the random chain is 100% by mass, the oxyalkylene chain added to the initiator (S1) consists only of random chains of oxyethylene groups and oxypropylene groups.
Of the oxyalkylene chain added to the initiator (S1), when it has a portion other than the random chain at the terminal portion, it is preferably an oxyethylene group. That is, after adding an oxyethylene group block chain to the initiator (S1), it is preferable to add a random chain of an oxyethylene group and an oxypropylene group to the terminal portion.

  The hydroxyl value of the polyol (A) is 10 to 100 mgKOH / g. 20-80 mgKOH / g is preferable, 20-70 mgKOH / g is more preferable, and 30-70 mgKOH / g is especially preferable. When the hydroxyl value is not less than the lower limit of the above range, the polyol (A) is preferable because the viscosity of the polyol (A) does not become too high. When the hydroxyl value is not more than the upper limit of the above range, the rigid foam is easily reduced in weight.

[Polyol (B)]
The polyol (B) is a polyether polyol having a hydroxyl value of 200 to 1,000 mgKOH / g, obtained by ring-opening addition polymerization of only propylene oxide to an initiator (S2) having 2 to 8 functional groups.
The initiator (S2) is the same as the initiator (S1) in the polyol (A), including preferred embodiments.

When all of the alkylene oxide used for the production of the polyol (B) is propylene oxide, the rigid foam tends to be open-celled, and foam shrinkage is easily prevented.
The hydroxyl value of the polyol (B) is 200 to 1,000 mgKOH / g. 300 to 900 mgKOH / g is preferable, and 300 to 800 mgKOH / g is particularly preferable. When the hydroxyl value is not less than the lower limit of the above range, the resulting rigid foam tends to be open cells, and thus foam shrinkage is easily prevented. When the hydroxyl value is not more than the upper limit of the above range, the viscosity of the polyol (B) is low. This is preferable because it is not too high.

[Polyol (C)]
Polyol (C) is a polyhydride having a hydroxyl value of 80 to 200 mgKOH / g, obtained by subjecting an initiator (S3) having 2 to 8 functional groups to ring-opening addition polymerization of propylene oxide and then ring-opening addition polymerization of ethylene oxide. It is an ether polyol. That is, in the polyol (C), the terminal portion of the oxyalkylene chain added to the initiator (S3) is an oxyethylene block chain, and the rest is an oxypropylene block chain.
The initiator (S3) is the same as the initiator (S1) in the polyol (A), including preferred embodiments.

By using the polyol (C) having an oxyethylene block chain at the terminal portion of the molecule, the cell is suppressed from becoming rough.
10-60 mass% is preferable among the alkylene oxide added to an initiator (S3), 20-50 mass% is more preferable, 25-40 mass% is especially preferable. When the proportion of the ethylene oxide is not less than the lower limit of the above range, the effect of suppressing the cell from becoming rough due to the use of the polyol (C) can be sufficiently obtained. When the amount is not more than the upper limit of the above range, the activity of the polyol (C) does not become too high, and the shrinkage of the foam hardly occurs.

  The hydroxyl value of the polyol (C) is 80 to 200 mgKOH / g. 85 to 180 mgKOH / g is preferable, 90 to 160 mgKOH / g is more preferable, and 100 to 140 mgKOH / g is particularly preferable. When the hydroxyl value is not less than the lower limit of the above range, the viscosity of the polyol (C) is preferably not too high, and when it is not more than the upper limit of the above range, the resulting rigid foam tends to be open-celled. It is easy to prevent shrinkage.

[Method for producing polyol]
The reaction for subjecting the initiator (S1), (S2), or (S3) to ring-opening addition polymerization of alkylene oxide is preferably performed in the presence of a catalyst.
The catalyst is preferably at least one selected from the group consisting of a double metal cyanide complex catalyst, a Lewis acid catalyst, and an alkali metal catalyst, and only one type is particularly preferable. When the above catalyst is used, it is easy to uniformly add alkylene oxide to the initiator.
As the double metal cyanide complex catalyst, a double metal cyanide complex catalyst in which an organic ligand is coordinated to zinc hexacyanocobaltate is preferable. Examples of the organic ligand include tert-butanol, tert-pentyl alcohol, ethylene glycol mono-tert-butyl ether, a combination of tert-butanol and ethylene glycol mono-tert-butyl ether, and the like.
Examples of the Lewis acid catalyst include BF ₃ complex, tris (pentafluorophenyl) borane, and tris (pentafluorophenyl) aluminum.
Examples of the alkali metal catalyst include alkali metal compounds such as cesium hydroxide, potassium hydroxide, and sodium hydroxide. In particular, potassium hydroxide is preferred.
As the catalyst used for the production of the polyol (A), (B) or (C) in the present invention, potassium hydroxide is most preferably used.

[Preferred Mode of Polyols (A), (B), and (C)]
As the polyol (A) in the present invention, a mixture of EO and PO (EO content is 20 to 80% by mass) in the presence of a potassium hydroxide catalyst is added to the initiator (S1) having 2 to 8 functional groups. A polyether polyol (A1) obtained by ring-opening addition polymerization and having a hydroxyl value of 10 to 100 mgKOH / g is preferred. Further, an alkylene obtained by subjecting an initiator (S1) having 2 to 8 functional groups to ring-opening addition polymerization of EO in the presence of a potassium hydroxide catalyst, followed by ring-opening addition polymerization of a mixture of EO and PO. 20 to 95% by mass of the oxide is EO, the proportion of the random chain present in the terminal portion is 10% by mass or more and less than 100% by mass of the oxyalkylene chain, and the hydroxyl value is 10 to 100 mgKOH / g. Ether polyol (A2) is preferred.
The polyol (B) in the present invention has a hydroxyl value of 200 to 1, obtained by ring-opening addition polymerization of only PO in the presence of a potassium hydroxide catalyst in an initiator (S2) having 2 to 8 functional groups. A polyether polyol (B1) of 000 mg KOH / g is preferred.
As the polyol (C) in the present invention, PO is subjected to ring-opening addition polymerization in the presence of a potassium hydroxide catalyst in an initiator (S3) having 2 to 8 functional groups, and then EO (the ratio of EO in alkylene oxide). Is a polyether polyol (C1) having a hydroxyl value of 80 to 200 mgKOH / g, obtained by ring-opening addition polymerization.

[Polyol content in the polyol composition (P)]
Content of the polyol (A) in a polyol composition (P) is 10-60 mass%, 20-60 mass% is preferable, 30-60 mass% is more preferable, 40-55 mass% is especially preferable. When the ratio of the polyol (A) is not less than the lower limit of the above range, even when the polyol system liquid contains a large amount of water, good storage stability of the polyol system liquid can be obtained and light weight can be suppressed while suppressing shrinkage deformation. The effect that a rigid foam can be produced is easily obtained. When the amount is not more than the upper limit of the above range, shrinkage or collapse due to insufficient strength of the cell is unlikely to occur.
When a polyol composition (P) contains a polyol (B), the content is 40-90 mass%, 45-90 mass% is more preferable, and 55-70 mass% is especially preferable. When the ratio of the polyol (B) is not less than the lower limit of the above range, good storage stability of the polyol system liquid can be easily obtained, and shrinkage deformation of the foam can be easily suppressed. When the amount is not more than the upper limit of the above range, the cell is hardly roughened.
When a polyol composition (P) contains a polyol (C), the content is 3-40 mass%, 3-15 mass% is preferable and 5-10 mass% is especially preferable. When the proportion of the polyol (C) is not less than the lower limit of the above range, the effect of suppressing the cell from becoming rough can be sufficiently obtained. Further, when the proportion of the polyol (C) is not more than the upper limit of the above range, shrinkage or crushing due to insufficient strength of the cell is difficult to occur.

  In particular, when the polyol composition (P) contains the polyol (A), the polyol (B), and the polyol (C), the proportion of the polyol (A) is 10 to 60 in 100% by mass of the polyol composition (P). % By mass is preferable, 20 to 60% by mass is preferable, and 30 to 50% by mass is particularly preferable. The proportion of the polyol (B) is preferably 37 to 87% by mass, more preferably 37 to 77% by mass, and particularly preferably 47 to 67% by mass. The proportion of the polyol (C) is preferably 3 to 15% by mass, particularly preferably 5 to 10% by mass. The reason for each upper limit and lower limit is the same as described above.

[Other active hydrogen compounds (D)]
The polyol composition (P) may contain, in addition to the polyol (A), polyol (B), and polyol (C), a compound having an active hydrogen atom (referred to as an active hydrogen compound) (D). Examples of the other active hydrogen compound (D) include other polyols not included in any of polyol (A), polyol (B), and polyol (C), polyhydric phenols, and aminated polyols. .
Examples of other polyols include polyether polyol, polyester polyol, and polycarbonate polyol.

As polyhydric phenols, non-condensable compounds such as bisphenol A and resorcinol, resol-type initial condensates obtained by condensation-bonding phenols with excess formaldehyde in the presence of an alkali catalyst, and this resole-type initial condensate are synthesized. Examples thereof include a benzylic type initial condensate reacted in a non-aqueous system, a novolak type initial condensate obtained by reacting excess phenols with formaldehyde in the presence of an acid catalyst, and the like. The number average molecular weight of these initial condensates is preferably about 200 to 10,000. In the above, phenols include phenol, cresol, bisphenol A, resorcinol and the like. Examples of formaldehydes include formalin and paraformaldehyde.
Examples of aminated polyols include polyether triamine (manufactured by Huntsman Corporation, trade name: Jeffermin) having a number average molecular weight of 5,000 and an amination rate of 95% obtained by subjecting PO to ring-opening addition polymerization to glycerol and amination. T-5000) and the like.
The proportion of the active hydrogen compound (D) in 100% by mass of the polyol composition (P) is preferably 0 to 10% by mass.

[Polyisocyanate compound (Y)]
The polyisocyanate compound (Y) in the present invention is not particularly limited, but is an aromatic, alicyclic or aliphatic polyisocyanate having two or more isocyanate groups; a mixture of two or more of the above polyisocyanates; Modified polyisocyanates obtained by modifying these are preferred.
Specific examples include tolylene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), polymethylene polyphenyl polyisocyanate (common name: crude MDI), xylylene diisocyanate (XDI), isophorone diisocyanate (IPDI), hexamethylene diisocyanate (HDI). And polyisocyanates such as these, or prepolymer-modified products thereof, nurate-modified products, urea-modified products, and carbodiimide-modified products. Of these, TDI, MDI, crude MDI, or modified products thereof are preferred. Crude MDI is particularly preferable in terms of easy availability and easy handling. The polyisocyanate compound (B) may be used alone or in combination of two or more.

The amount of the polyisocyanate compound (Y) used is represented by 100 times the number of isocyanate groups with respect to the total number of active hydrogen atoms contained in the polyol composition (P) (usually, the numerical value represented by 100 times is called the isocyanate index). ), 10 to 100 are preferable. 20-80 are more preferable and 30-70 are especially preferable. If the isocyanate index is equal to or higher than the lower limit of the above range, open cells tend to be formed, and shrinkage is easily suppressed. If it is below the upper limit of the above range, it is easy to reduce the weight.
When manufacturing a rigid foam by a spray method, it is preferable that the usage-amount of a polyisocyanate compound (Y) and a polyol compound (P) is about 1: 1 by volume ratio.

[Foaming agent]
As the foaming agent, water, hydrocarbon compounds, hydrofluorocarbons (also referred to as HFC compounds), methylene chloride, and other halogenated hydrocarbons are preferable. Two or more foaming agents may be used in combination. The blowing agent preferably contains at least water.
Examples of the hydrocarbon compound include butane, normal pentane, isopentane, cyclopentane, hexane, cyclohexane and the like. Of these, normal pentane, isopentane, and cyclopentane are preferable.
Examples of HFC compounds include 1,1,1,2-tetrafluoroethane (HFC-134a), 1,1,1,3,3-pentafluoropropane (HFC-245fa), 1,1,1,3. , 3-pentafluorobutane (HFC-365mfc) and the like.
Among these, it is preferable to use water alone or to use water and one or more other foaming agents in combination. As the blowing agent used in combination with water, hydrocarbon compounds and HFC compounds are preferable. As the hydrocarbon compound used in combination with water, cyclopentane, isopentane, normal pentane or a mixture thereof is particularly preferable. As the HFC compound used in combination with water, HFC-134a, HFC-245fa, HFC-365mfc or these Mixtures are preferred. In consideration of the environment, it is more preferable to use only water as the foaming agent.

The present invention is particularly suitable for a system that uses a large amount of a foaming agent for weight reduction, and is also suitable for a system that uses a large amount of water as a foaming agent.
Specifically, when water is used alone as the foaming agent, or when water and one or more other foaming agents are used in combination, the amount of water used is 100 of the polyol composition (P). 15-60 mass parts is preferable with respect to mass parts (water is not calculated as a polyol. The same applies hereinafter). 25-60 mass parts is more preferable, and 30-50 mass parts is especially preferable. When the amount of water used is not less than the lower limit of the above range, the obtained rigid foam is easily reduced in weight, and when it is not more than the upper limit of the above range, good mixing properties of water and the polyol composition (P) are good. Is easy to obtain.

[Flame retardants]
In the present invention, a flame retardant is used. The flame retardant is preferably a phosphorus-based flame retardant, and the compounds are tricresyl phosphate (TCP), triethyl phosphate (TEP), tris (β-chloroethyl) phosphate (TCEP), tris (β-chloropropyl) phosphate (TCPP). Etc.) are preferred.
10-100 mass parts is preferable with respect to 100 mass parts of a polyol composition (P), and, as for the usage-amount of a flame retardant, 30-80 mass parts is more preferable, and 40-70 mass parts is especially preferable. When the amount of the flame retardant used is not less than the lower limit of the above range, the flame retardancy of the foam is favorably improved. When the amount is not more than the upper limit of the above range, good storage stability of the polyol system liquid is easily obtained.
One flame retardant may be used, or two or more flame retardants may be mixed and used.

[catalyst]
The catalyst used in the present invention is not particularly limited as long as it is a urethanization catalyst that accelerates the urethanization reaction. For example, amines such as N, N, N ′, N ″, N ″ -pentamethyldiethylenetriamine, bis (2-dimethylaminoethyl) ether, triethylenediamine, N, N, N ′, N′-tetramethylhexamethylenediamine Examples of the catalyst include reactive amine-based catalysts such as N, N, N′-trimethylaminoethylethanolamine; and organometallic catalysts such as dibutyltin dilaurate. Moreover, you may use together the catalyst which accelerates | stimulates the trimerization reaction of an isocyanate group, and carboxylic acid metal salts, such as potassium acetate and potassium 2-ethylhexanoate, etc. are mentioned. As for the usage-amount of a urethanization catalyst, 0.1-30 mass parts is preferable with respect to 100 mass parts of a polyol composition (P). Moreover, the usage-amount of the catalyst which accelerates | stimulates a trimerization reaction has preferable 0.1-30 mass parts with respect to 100 mass parts of a polyol composition (P).
As a catalyst, it is preferable not to use a metal catalyst but to use only an amine catalyst or a reactive amine catalyst because of environmental pollution.

[Foam stabilizer]
In the present invention, a foam stabilizer is used to form good bubbles. Examples of the foam stabilizer include silicone foam stabilizers and fluorine-containing compound foam stabilizers. In general, in addition to the silicone-based foam stabilizer used for producing rigid urethane foam, a silicone-based foam stabilizer used for producing highly breathable flexible urethane foam may be used. Although the usage-amount of a foam stabilizer may be selected suitably, 0.1-10 mass parts is preferable with respect to 100 mass parts of a polyol composition (P).

[Other ingredients]
In the present invention, any compounding agent can be used in addition to the above-described polyol composition (P), polyisocyanate compound (Y), foaming agent, flame retardant, foam stabilizer, and catalyst. Compounding agents include fillers such as calcium carbonate and barium sulfate; antioxidants such as antioxidants and UV absorbers; plasticizers, colorants, antifungal agents, foam breakers, dispersants, anti-discoloration agents, etc. Can be mentioned.

[Method of manufacturing rigid foam]
The method for producing a rigid foam is not particularly limited, but the present invention is particularly suitable for a method for producing a rigid foam by a spray method.
The spray method prepares a solution (polyol system liquid) containing a polyol composition (P), a foaming agent, a flame retardant, a foam stabilizer, a catalyst, and a compounding agent as required, and the polyol system liquid and the polyisocyanate compound ( Y) is a foaming method in which a polyisocyanate liquid containing Y is reacted while sprayed on a construction surface.
The spray method is a method of directly manufacturing a rigid foam at a construction site, and has advantages such as that construction costs can be suppressed and construction can be performed even on uneven construction surfaces without gaps. Therefore, the spray method is often employed when constructing a heat insulating material made of hard foam on a wall, ceiling or the like at a construction site. Specific construction examples include heat insulating materials for condominiums, office buildings, prefabricated refrigerated warehouses, and the like.
Various methods are known as the spray method, and airless spray foaming in which a polyol component and a polyisocyanate component are mixed and foamed with a mixing head is particularly preferable.

The present invention is suitable for a method for producing a lightweight rigid foam. Specifically, it is preferable that the core density of the rigid foam obtained by the production method of the present invention is 5 to 12 kg / m ³ . 7 to 12 kg / m ³ is more preferable, and 8 to 12 kg / m ³ is particularly preferable.
In the present invention, the core density of the rigid foam is a value obtained by a measurement method based on JIS K7222.
The rigid foam obtained by the production method of the present invention is easy to reduce the weight and is particularly preferable for building and building materials because it contains a flame retardant.

According to the present invention, it is possible to produce an ultralight rigid foam that does not shrink and deform by using a large amount of foaming agent. Preferably, it is possible to manufacture an ultralight rigid foam that is free from shrink deformation and has no roughened cell.
In addition, in the method using water as a blowing agent, good storage stability of the polyol system liquid can be obtained even when a large amount of water is used, and the polyol composition (P) and the polyisocyanate compound (Y) are good. It is possible to produce an ultra-light rigid foam that is easy to mix and has no shrinkage deformation. Preferably, while using a lot of water, it is possible to produce an ultralight rigid foam that can provide good storage stability of the polyol system liquid, is free from shrinkage deformation, and has no roughened cells.
For example, as shown in the examples described later, while using 40 parts by mass of water with respect to 100 parts by mass of the polyol composition (P), good storage stability of the polyol system liquid is obtained, and the core density is about It is possible to satisfactorily manufacture a rigid foam that has been ultra-lightened to about 10 kg / m ³ .

In addition, the method of the present invention is suitable for spray foaming because the storage stability of the polyol system liquid is good, and even if a large amount of flame retardant is blended, an ultralight rigid foam can be produced satisfactorily. is there.
That is, when a rigid foam is produced by a slab foaming method or an injection method, the mixing ratio of the polyol system liquid and the polyisocyanate liquid can be freely determined. However, in the spray foaming method, the mixing ratio is usually a volume. There is a restriction of about 1: 1 in ratio.
On the other hand, since the spray foaming method is mainly used for building applications, flame retardancy is required. In the spray foaming method in which the polyol system liquid and the polyisocyanate liquid are mixed at a volume ratio of 1: 1, flame retardancy can be improved by adopting a nurate formulation (a formulation that produces a trimer). Since it is difficult, it is necessary to add a lot of flame retardants. Further, when a polyol containing no aromatic ring or N atom is used as the polyol (A), it is difficult to ensure sufficient flame retardancy of the obtained rigid foam, so it is necessary to add a large amount of flame retardant. Become. In particular, in a system that uses a lot of water, if a large amount of a flame retardant is blended, there is a concern that compatibility may be lowered. The decrease in compatibility causes the foam to shrink or collapse, or the cell becomes rough.
On the other hand, the manufacturing method of the rigid foam of the present invention is an ultra-lightweight that has good storage stability of the polyol system liquid and has no shrinkage deformation even if it contains a large amount of water and a large amount of flame retardant. Rigid foam can be produced. Preferably, it is possible to produce an ultralight rigid foam having good flame retardancy, no shrink deformation, and no roughened cells.
For example, as shown in the examples described later, good storage stability of the polyol system liquid while using 40 parts by mass of water and 50 parts by mass of the flame retardant with respect to 100 parts by mass of the polyol composition (P). And a rigid foam having a core density reduced to about 10 kg / m ³ can be favorably manufactured by a spray method.

EXAMPLES Hereinafter, although an Example demonstrates this invention concretely, this invention is not limited to these Examples.
The hydroxyl value was measured according to JIS K1557 (1970 edition).

The raw materials used in the examples and comparative examples are as follows.
[Polyol (A)]
Polyol (A-1): Hydroxyl group obtained by subjecting EO to ring-opening addition polymerization in the presence of a potassium hydroxide catalyst using glycerin as an initiator, and then successively subjecting a mixture of PO and EO to random ring-opening addition polymerization. A polyether polyol having a value of 48.5 mgKOH / g. Of the total amount of EO and PO, the proportion of EO is 67% by mass. Among the oxyalkylene chains added to the initiator, random chains of oxyethylene groups and oxypropylene groups in the terminal portion (hereinafter referred to as PO / EO random). The proportion of the chain is 71% by mass.
Polyol (A-2): Polyether polyol having a hydroxyl value of 48.1 mgKOH / g, obtained by random ring-opening addition polymerization of a mixture of PO and EO in the presence of a potassium hydroxide catalyst using glycerol as an initiator . Of the total amount of EO and PO, the proportion of EO is 80% by mass, and 100% by mass of the oxyalkylene chain added to the initiator is a PO / EO random chain.

[Polyol (B)]
Polyol (B-1): A polyether polyol having a hydroxyl value of 400 mgKOH / g, obtained by ring-opening addition polymerization of PO in the presence of a potassium hydroxide catalyst using glycerol as an initiator.
Polyol (B-2): A polyether polyol having a hydroxyl value of 760 mgKOH / g, obtained by ring-opening addition polymerization of only PO in the presence of a potassium hydroxide catalyst using ethylenediamine as an initiator.
[Polyol (C)]
Polyol (C-1): Polyol having a hydroxyl value of 112 mgKOH / g, obtained by subjecting PO to ring-opening addition polymerization in the presence of a potassium hydroxide catalyst using glycerin as an initiator, followed by ring-opening addition polymerization of EO. Ether polyol. Of the total amount of EO and PO, the proportion of EO is 33% by mass.

[Comparison polyol (D)]
Polyol (D-1): A polyether polyol having a hydroxyl value of 56 mgKOH / g, obtained by ring-opening addition polymerization of PO in the presence of a potassium hydroxide catalyst using glycerol as an initiator.
Polyol (D-2): A polyether polyol having a hydroxyl value of 56 mgKOH / g, obtained by random ring-opening addition polymerization of a mixture of PO and EO in the presence of a potassium hydroxide catalyst using glycerol as an initiator. Of the total amount of EO and PO, the proportion of EO is 7% by mass.
Polyol (D-3): Polyol having a hydroxyl value of 56 mgKOH / g, obtained by subjecting PO to ring-opening addition polymerization in the presence of a potassium hydroxide catalyst using glycerin as an initiator, followed by ring-opening addition polymerization of EO. Ether polyol. In the total amount of EO and PO, the ratio of EO is 13% by mass.
Polyol (D-4): Polyol having a hydroxyl value of 56 mgKOH / g, obtained by subjecting PO to ring-opening addition polymerization in the presence of a potassium hydroxide catalyst using glycerin as an initiator, and then subsequently subjecting EO to ring-opening addition polymerization. Ether polyol. Of the total amount of EO and PO, the proportion of EO is 20% by mass.

Flame retardant A: Tris (β-chloropropyl) phosphate (trade name: FYLOL PCF
ICL-IP JAPAN).
Foaming agent A: water.
Foam stabilizer A: Silicone foam stabilizer (trade name: SF2938F, manufactured by Dow Corning Toray).
Foam stabilizer B: Silicone foam stabilizer (trade name: SRX-298, manufactured by Toray Dow Corning).
Catalyst A: Amino alcohol catalyst (trade name: POLYCAT 52, manufactured by Air Products Japan).
Polyisocyanate compound (Y-1): Crude MDI, trade name: Coronate 1130, viscosity (25 ° C.): 120 mPa · s, NCO content: 31.2% (manufactured by Nippon Polyurethane Industry Co., Ltd.).

The evaluation shown in the table was performed by the following method.
[Box-free foaming]
Polyol system liquid was prepared by mixing polyol, foaming agent, foam stabilizer, catalyst and flame retardant in the formulation shown in Tables 1-4.
The liquid temperature of the obtained polyol system liquid and polyisocyanate compound (Y-1) were each kept at 15 ° C., and these were used for 3 minutes per minute using a stirrer in which a disc type stirring blade was attached to a drilling machine manufactured by Hitachi, Ltd. The mixture was stirred at 000 rpm for 4 seconds to obtain a mixed solution. Thereafter, the mixed solution is filled into a wooden mold having a length of 150 mm × width 150 mm × height 150 mm equipped with a polyethylene release bag, foamed, and an ultralight rigid foam having a box core density of about 10 kg / m ³ is obtained. Manufactured.
In addition, the unit of the numerical value showing a compounding quantity in a table | surface is a mass part. However, the amount of polyisocyanate compound used is represented by the isocyanate index (INDEX).
The reactivity in box-free foaming, the density of the obtained rigid foam, shrinkage, cell appearance, and storage stability of the polyol system liquid were evaluated by the following methods. The evaluation results are shown in Tables 1 to 4.

(Reactivity)
The mixing start time of the polyol system liquid and the polyisocyanate compound is 0 second, the time until the liquid mixture starts to foam is the cream time (seconds), the time when the liquid mixture begins to foam and the rise of the foam stops is the rise time (Seconds). (Box core density)
The core portion of the obtained rigid polyurethane foam was cut into a cube having a side of 100 mm, and the density was measured according to JIS K7222. Density measurement was not performed for those having large shrinkage deformation.
(Shrinkage)
In the above box-free foaming, after the rise of the foam due to foaming stopped, the foam was left at 20 ° C. for 30 minutes, and the appearance was observed. Evaluation was made according to the following criteria.
○ (good): No deformation. Good.
Δ (possible): Partial deformation occurred due to shrinkage.
X (impossible): The whole was crushed by shrinkage. Bad.
(Cell appearance)
Of the surfaces of the rigid foam obtained by box-free foaming, the surface on the lower side (bottom side of the wooden box) with respect to the foaming direction (the height direction of the box) was used as the surface of the skin portion. Further, the surface of a cube having a side of 100 mm cut out from the core portion of the rigid foam was used as the surface of the core portion.
With respect to the respective surfaces of the skin part and the core part, the presence or absence of non-uniform cell portions (portion where the cells are rough) was visually observed and evaluated according to the following criteria.
A (Excellent): There is no portion where the cell is rough. The cells are fine and uniform.
○ (good): There is no portion where the cell is rough. Uniform cell.
Δ (possible): The cell is partially rough.
X (impossible): The cell is rough as a whole. Bad.

(Storage stability of polyol system liquid)
The polyol system solution prepared in box-free foaming was stored at 20 ° C. for 1 month, then visually observed and evaluated according to the following criteria.
○ (good): No turbidity, separation, precipitation or solidification occurs, and it is transparent. Good.
X (impossible): One or more of turbidity, separation, precipitation, and solidification occurred. Bad.

[Spray construction test]
A spray construction test was conducted on Example 5, Example 23, and Example 24.
That is, a polyol system liquid was prepared by mixing a polyol, a foaming agent, a foam stabilizer, a catalyst and a flame retardant in the formulations shown in Tables 1 and 3.
The obtained polyol system liquid and polyisocyanate compound (Y-1) are installed vertically assuming a wall surface using a spray foaming machine under conditions of a liquid temperature of 40 ° C., a room temperature of 20 ° C., and a volume ratio of 1: 1. A rigid foam was manufactured by spraying and applying to a flexible board (base material) of 600 mm × 600 mm × 5 mm. As the spray foaming machine, MODEL N-1600UE-HYD foaming machine manufactured by Nippon Urethane Engineering Co., Ltd., to which a D gun manufactured by Gasmer Co. was connected, was used. For the spraying, after a lower spray layer having a thickness of 1 mm was applied, two layers were applied so that the thickness of one layer was 25 to 30 mm, and a total of three layers were laminated.
The core density, shrinkage, adhesion, flame retardancy, and thermal conductivity in spraying were evaluated by the following methods. The evaluation results are shown in Tables 1 and 3.

(Core density)
Based on JIS K7220, the core part was cut into a rectangular parallelepiped of 200 mm × 200 mm × 25 mm the day after spraying, and the density was measured. (Shrinkage)
In the spray application, after the foam rise due to foaming stopped, the foam was left at 20 ° C. for 30 minutes, and the appearance was observed. Those with no deformation were marked with ◯ (good), and those with shrinkage deformation were marked with x (bad). (Adhesiveness)
The end of the applied foam was cut and the feel when the foam was peeled off from the substrate was confirmed and evaluated according to the following criteria.
○ (good): Foam remains on the base material, making it difficult to peel off the foam due to strong adhesion. Good.
X (impossible): The foam does not remain on the substrate, and the foam easily peels off. Bad.
(Burn test (flame retardant))
About the obtained rigid foam, the self-extinguishing test was done according to the test method B of JIS-A-9511, and the combustion time (unit: second) and the combustion length (unit: mm) were measured. The shorter the combustion length and the shorter the combustion time, the better the flame retardancy. (Thermal conductivity)
The thermal conductivity (unit: mW / m · K) was measured using a thermal conductivity measuring device (product name: Auto Lambda HC-074, manufactured by Eiko Seiki Co., Ltd.) in accordance with JIS A1412.

In Table 1, Examples 2 to 5 are examples, and Examples 1 and 6 are comparative examples.
As shown in the results of Table 1, Examples 2 to 5 containing the polyol (A) in the range of 10 to 60% by mass in the polyol composition (P) are the same as those in Example 1 containing only the polyol (B). Compared to this, the shrinkage and the cell appearance were improved. The storage stability of the polyol system liquids of Examples 2 to 5 was good.
In Example 1 where the polyol composition (P) was composed only of the polyol (B), although the storage stability was good, the foam partially contracted and deformed. In addition, the cells are generally rough in both the core part and the skin part, and it is considered that the shrinkage deformation of the foam occurred due to poor mixing of the polyol system liquid and the polyisocyanate compound.
On the other hand, foam collapse occurred in Example 6 in which the content of the polyol (A) was 70% by mass. It is considered that the foam was crushed due to insufficient strength of the cell because there was no portion where the cell was rough in the skin part.
Further, in the spray application test, in Example 5, no shrinkage of the foam was observed, and a rigid foam excellent in adhesion and flame retardancy could be obtained even at a low density.

In Table 2, Examples 11 to 12 are examples, and Example 13 is a comparative example.
In the example of Table 1, polyol (B-1) obtained by ring-opening addition polymerization of PO to glycerin (initiator) was used as the polyol (B). However, in the example of Table 2, PO was opened to ethylenediamine (initiator). Cycloaddition-polymerized polyol (B-2) was used.
As shown in the results of Table 2, Examples 11 and 12 in which the polyol composition (P) contains 20 mass% or 40 mass% of the polyol (A) in addition to the polyol (B) are polyol system liquids The storage stability was good, and although the cells were partially rough, a rigid foam having no shrinkage was obtained. Compared with the examples in Table 1, the reactivity is high. It is considered that the reason why the reactivity is high is that an amine compound is used as an initiator.
On the other hand, in Example 13 in which the content of the polyol (A) was 80% by mass, the storage stability of the polyol system liquid was deteriorated and the foam was crushed.

In Table 3, Examples 21 to 25 are examples.
Table 3 is an example using polyol (C) in addition to polyols (A) and (B).
In all cases, the shrinkage, the cell appearance, and the storage stability of the polyol system liquid were good.
In addition, when Examples 4 and 5 in Table 1 and Examples 21 to 24 in Table 3 are compared, the contents of polyols (A) and (B) are almost the same, and by adding polyol (C), the cell appearance is improved. You can see that it has improved.
In the spray application test, in Examples 23 and 24, no shrinkage of the foam was observed, and a rigid foam excellent in adhesion and flame retardancy could be obtained even at a low density.

In Table 4, Examples 31-34 are comparative examples.
Table 4 shows an example in which the polyol (A) was not used and comparative polyols (D-1) to (D-4) were used instead. In all cases, foam collapse occurred. Moreover, the storage stability of the polyol system liquid of Examples 31-33 was also bad.
That is, Example 31 is an example in which a polyol (D-1) using only PO as an alkylene oxide added to the initiator is used instead of the polyol (A-1). The storage stability of the polyol system liquid was poor and foam shrinkage occurred.
In Example 32, 100% by mass of the oxyalkylene chain is a random chain of an oxyethylene group and an oxypropylene group, but among the alkylene oxides added to the initiator, a polyol (D- This is an example using 2). The storage stability of the polyol system liquid was poor and foam shrinkage occurred.
In Example 33, an oxypropylene group block chain and an oxyethylene group block chain were added in this order to the initiator, and the polyol (the content of EO in the alkylene oxide added to the initiator was as small as 13% by mass). This is an example using D-3). The storage stability of the polyol system liquid was poor and foam shrinkage occurred.
Example 34 is a polyol in which the content of EO in the alkylene oxide added to the initiator is 20% by mass, but an oxypropylene group block chain and an oxyethylene group block chain are added to the initiator in this order. This is an example using (D-4). Although the storage stability of the polyol system liquid was good, foam shrinkage occurred.

Claims (9)

In the method for producing a rigid foam synthetic resin by reacting the polyol composition (P) and the polyisocyanate compound (Y) in the presence of a foaming agent, a flame retardant, a foam stabilizer and a catalyst,
The polyol composition (P) is a polyol composition having an average hydroxyl number of 2 to 8 and an average hydroxyl value of 100 to 700 mgKOH / g, and contains 10 to 60% by mass of the following polyol (A). A method for producing a rigid foam synthetic resin.
Polyol (A): a polyether polyol having a hydroxyl value of 10 to 100 mgKOH / g, obtained by ring-opening addition polymerization of alkylene oxide to an initiator (S1) having 2 to 8 functional groups, 20 to 95% by mass is ethylene oxide, the terminal part is capped with a random chain of oxyethylene group and oxypropylene group, and the proportion of the random chain present in the terminal part is 10 to 100% by mass of the oxyalkylene chain A polyether polyol. The manufacturing method of the hard foam synthetic resin of Claim 1 in which the said polyol composition (P) contains 40-90 mass% of following polyols (B).
Polyol (B): A polyether polyol having a hydroxyl value of 200 to 1,000 mgKOH / g, obtained by subjecting an initiator (S2) having 2 to 8 functional groups to ring-opening addition polymerization of only propylene oxide. The manufacturing method of the hard foam synthetic resin of Claim 1 or 2 with which the said polyol composition (P) contains 3-40 mass% of the following polyol (C).
Polyol (C): A polyether having a hydroxyl value of 80 to 200 mgKOH / g, obtained by subjecting an initiator (S3) having 2 to 8 functional groups to ring-opening addition polymerization of propylene oxide and then ring-opening addition polymerization of ethylene oxide. Polyol.   The said foaming agent contains water, The usage-amount of this water is 15-60 mass parts with respect to 100 mass parts of the said polyol composition (P), It is any one of Claims 1-3. Manufacturing method of hard foam synthetic resin.   The manufacturing method of the hard foam synthetic resin as described in any one of Claims 1-4 which uses only water as the said foaming agent.   The manufacturing method of the hard foam synthetic resin as described in any one of Claims 1-5 whose usage-amount of the said flame retardant is 10-100 mass parts with respect to 100 mass parts of a polyol composition (P). .   The manufacturing method of the hard foam synthetic resin as described in any one of Claims 1-6 whose usage-amount of the said polyisocyanate compound (Y) is 10-100 by an isocyanate index | exponent. The manufacturing method of the hard foam synthetic resin as described in any one of Claims 1-7 whose core density of the hard foam synthetic resin obtained is 5-12 kg / m < ³ >.   The manufacturing method of the hard foam synthetic resin as described in any one of Claims 1-8 which manufactures a hard foam synthetic resin by the spray method.