JPH11292949A - Method for producing rigid isocyanurate spray foam - Google Patents

Abstract

(57) [Problem] To provide a production method capable of achieving improvement of initial foaming property, improvement of workability, and reduction of foam density, which have conventionally been problems in the production of rigid isocyanurate spray foam. A polyol and a polyisocyanate are used as a catalyst,
In a method for producing a rigid isocyanurate spray foam by reacting in the presence of a foaming agent, a foam stabilizer and, if necessary, other auxiliaries, one or more kinds of amine compounds selected from amine compounds as an initial foamability improver. A rigid isocyanurate spray foam is produced using an amine compound.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a rigid isocyanurate spray foam, and more particularly to a method for producing a rigid isocyanurate foam by a spray application method using an impingement mixing type high pressure spraying apparatus.

[0002]

2. Description of the Related Art Rigid urethane foam is widely used for heat insulating materials in electric refrigerators and for building materials such as lamination boards. Among them, the demand for a rigid foam formed by a spraying method as a heat insulating material for constructing a house or a building has been rapidly increasing recently due to a shortened construction period and the like. In this application, high flame retardancy may be required, and in addition to the conventional urethane-based spray foam, isocyanurate-based spray foam into which isocyanurate bond having high heat resistance is introduced is spreading. The isocyanurate bond is a bond in which the polyisocyanate is self-trimerized, and is produced by reacting the polyisocyanate with the raw material and water in stoichiometric excess.

[0003] Generally, a hard spray foam is prepared by mixing a polyol with water which reacts with a fluorocarbon compound as a foaming agent and a polyisocyanate to foam carbon dioxide gas, and further comprises a catalyst and, if necessary, other auxiliaries. While mixing and spraying the two liquids of the mix and the polyisocyanate with a spray foaming machine, a foaming reaction is caused on an adhesive surface such as a wall to form a cured product. In such a manufacturing method by spray molding, when the temperature in winter is low, the initial foaming reaction of the spray stock solution sprayed on the wall or the like becomes insufficient, and the foaming is delayed, so that the liquid drips and the moldability deteriorates. Problems such as an increase in the density of the particles. In isocyanurate-based spray foams, polyisocyanate self 3
The reaction at a low temperature is less likely to occur because of the high activation energy of the quantification reaction. A CFC-based compound used as a foaming agent is not easily solved because it is easily vaporized and initial foaming is apt to occur, but on the contrary, heat of vaporization is deprived. The CFC-based blowing agent should be eliminated due to environmental problems. On the other hand, a system using water as a foaming agent has been studied. However, the reaction between water and polyisocyanate is unlikely to occur at low temperatures, and the reaction immediately generates carbon dioxide gas to improve the initial foaming. In addition, foams that use a large amount of water are likely to cause problems such as deterioration of physical properties and deterioration of adhesion to an adherend.

[0004] That is, there is a need for a stock solution system in which the sprayed stock solution is immediately foamed.

In the hard isocyanurate spray formulation, it is important to increase the reactivity, and therefore, a highly reactive amine polyol is used or the number of catalysts used is increased. However, even if the number of used catalysts is simply increased, the improvement in reactivity is limited, and it is difficult to improve the initial foaming property by isocyanurate spray foaming.

[0006]

DISCLOSURE OF THE INVENTION The present invention has been made in view of the above circumstances, and has improved the initial foaming property, the workability, and the foaming property, which have been problems in the production of a rigid isocyanurate spray foam. An object of the present invention is to provide a manufacturing method capable of achieving a higher density.

[0007]

Means for Solving the Problems As a result of intensive studies on a hard isocyanurate spray foam system, the present inventors have found that a rigid isocyanurate spray formulation can be prepared by using an amine compound having a specific chemical structure as an initial foaming property improver. The present inventors have found that the initial foamability can be improved and that a low-density foam can be produced with good moldability, and the present invention has been completed. That is, the present invention provides a method for producing a rigid isocyanurate spray foam by reacting a polyol and a polyisocyanate in the presence of a catalyst, a foaming agent, a foam stabilizer and, if necessary, other auxiliaries. The following general formula (1)
A method for producing a rigid isocyanurate spray foam, comprising using one or more amine compounds selected from the amine compounds represented by (5) to (5).

[0008]

Embedded image

(Wherein, R1 to R4 each independently represent a lower alkyl group having 1 to 4 carbon atoms or hydrogen;
Represents the number of )

[0010]

Embedded image

(Wherein, R5 to R10 each independently represent a lower alkyl group having 1 to 4 carbon atoms or hydrogen; x, y, z
Each independently represents a number in the range of 1 to 50. A represents glycerin or trimethylolpropane. )

[0012]

Embedded image

(In the formula, b represents an integer in the range of 2 to 8.)

[0014]

Embedded image

(Wherein R11 and R12 each independently represent a lower alkyl group having 1 to 4 carbon atoms or hydrogen, A represents an oxygen or nitrogen group. R13 has no bonding group when A is an oxygen group. And A represents hydrogen when A is a nitrogen group, B represents hydrogen when A is an oxygen group, represents a hydroxyalkyl group when A is a nitrogen group, and c represents an integer in the range of 1 to 3. )

[0016]

Embedded image

(In the formula, d represents an integer of 2 to 12.) Hereinafter, the present invention will be described in detail.

As the initial foamability improver used in the production method of the present invention, an amine compound having active hydrogen represented by the above general formulas (1) to (5) can be used.

The amine compound represented by the general formula (1) is a polyoxyalkylene polyamine obtained by reacting polypropylene glycol and / or polyethylene glycol with ammonia at a high temperature and a high pressure. Amine compounds having various molecular weights can be obtained depending on the molecular weight. Although the molecular weight is not particularly limited, it is generally 200 to 4000, and more preferably a compound having a molecular weight of 200 to 600.

The amine compound represented by the general formula (2) is a compound obtained by reacting ammonia with a polyoxyalkylene polyol using glycerin or trimethylolpropane as a raw material, and the molecular weight of the polyoxyalkylene polyol as a raw material. Thus, amine compounds having various molecular weights can be obtained. Although the molecular weight is not particularly limited, it is generally 200 to 400.
0, more preferably a compound having a molecular weight of 200 to 600.

The amine compound represented by the general formula (3) is obtained by reacting and adding acrylonitrile to a diol having 2 to 8 carbon atoms and then performing a hydrogenation reaction. Although the molecular weight is not particularly limited, compounds in which the value of b in the general formula (3) is 2 to 4 are particularly desirable.

The amine compound represented by the general formula (4) is obtained by reacting ethylene oxide and / or propylene oxide with a polyoxyalkyleneamine or polyethylene polyamine obtained by reacting ammonia with ethylene oxide and / or propylene oxide. The molecular weight is not particularly limited, but the value of c in the general formula (4) is 1 to
Two compounds are desirable.

The compound represented by the general formula (5) is a compound called alkylenediamine, and its molecular weight is not particularly limited, but a compound having a value of d in the general formula (5) of 2 to 6 is used. desirable.

The compounds represented by formulas (1) to (5) can be used in any combination, but it is more preferable to use a small amount of ethylenediamine.

The amount of the compounds represented by the general formulas (1) to (5) is not particularly limited, but is usually from 0.02 to 50 parts by weight based on 100 parts by weight of the polyol. It is preferably 3 to 20 parts by weight for a compound having a large molecular weight, and 0.2 to 10 parts by weight for a compound having a small molecular weight.

The initial foam improver used by the production method of the present invention reacts quickly with the polyisocyanate to generate heat of reaction. For this reason, it is presumed that the reaction between water and urea bond-forming polyisocyanate is promoted to easily generate carbon dioxide gas, and the initial foaming property is improved.

The reaction between water and polyisocyanate is promoted by a tertiary amine catalyst called a foaming catalyst.
The reaction is not fast with the foaming catalyst alone, and the initial foaming properties cannot be said to be sufficient in the isocyanurate spray formulation.
In the production method of the present invention, the initial foaming property can be improved only by the amine compound represented by the aforementioned general formulas (1) to (5) without using the foaming catalyst. It is more preferable to use a combination of the above and an initial foaming property improver, since the initial foaming property can be further improved.

In the present invention, the foaming catalyst is a tertiary amine catalyst which mainly promotes the reaction between water and polyisocyanate, and is, for example, N, N, N ', N ", N" -pentamethyldiethylenetriamine, bis (2-dimethylaminoethyl) ether, N, ', N', N ", N" -pentamethyldipropylenetriamine, N, N-dimethylaminoethoxyethanol, N, N, N'-trimethylaminoethoxyethanol , N, N, N ′, N ″,
N ″ ′, N ′ ″-hexamethyltriethylenetetramine, N, N, N ′, N ″ -tetramethyl-N ″-
(2-hydroxylethyl) triethylenediamine,
N, N, N ′, N ″ -tetramethyl- (2-hydroxylpropyl) triethylenediamine and the like, among which more preferred are N, N, N ′, N ″,
N ″ -pentamethyldiethylenetriamine, bis (2
-Dimethylaminoethyl) ether. These foaming catalysts may be used alone and in combination with the initial foaming property improver, or several kinds thereof may be mixed and used in combination with the initial foaming property improver. The amount of the foaming catalyst used in the production method of the present invention is not particularly limited, but is usually 0.02 to 10 parts by weight, more preferably 0.1 to 10 parts by weight, based on 100 parts by weight of the polyol. -5 parts by weight. In addition, as a catalyst used in the production method of the present invention, a metal catalyst such as a tertiary amine catalyst, an isocyanurate catalyst, an organotin compound, and an organic lead compound other than the foaming catalyst described above can be used.
Although the tertiary amine catalyst is not particularly limited, for example, triethylenediamine, tetramethylhexamethylenediamine, dimethylcyclohexylamine,
-Methylimidazole, 1,2-dimethylimidazole, 1- (3-dimethylaminopropyl) imidazole, 1-n-butyl-2-methylimidazole, 1-isobutyl-2-methylimidazole and the like, preferably triethylenediamine; 1,2-Dimethylimidazole is utilized. Examples of the isocyanurate catalyst include, but are not particularly limited to, alkali metal salts represented by potassium such as potassium 2-hexylhexanoate and potassium acetate, and quaternary ammonium such as trimethyl (2-hydroxypropyl) ammonium 2-hexanote. Salts and the like can be mentioned, and potassium 2-ethylhexanoate is preferably used. In addition, organotin and organolead are used as metal catalysts indispensable for spray application.

The polyol used in the present invention may be any of the known tertiary amino group-containing polyols, oxyalkylated polyhydric alcohols or polyester polyols used in spray formulations, as well as flame-retardant polyols and halogen-containing polyols. Polyols and the like. These polyols can be used alone, or can be used by being appropriately mixed and used in combination.

As the tertiary amino group-containing polyol,
For example, in addition to ammonia and hydrazine as initiators, aliphatic polyamine compounds such as ethylenediamine, diethylenetriamine, and triethylenetetramine; heterocyclic polyamine compounds such as N-aminoethylpiperazine; toluenediamine; diphenylmethane-4,4′-diamine; Aromatic polyamine compounds, alkanolamine compounds such as mono-, di- or tri-ethanolamine; or polyols obtained by adding an alkylene oxide such as ethylene oxide or propylene oxide to a mixture thereof. Examples of the oxyalkylated polyhydric alcohol include, as an initiator, a polyhydric alcohol such as glycol, glycerin, bisphenol, pentaeristol, trimethylolpropane, or sucrose, or an alkylene oxide such as ethylene oxide or propylene oxide added to a mixture thereof. Polyol obtained by the above method. As polyester polyols, adipic acid, maleic acid, aliphatic polycarboxylic acids such as fumaric acid,
Alternatively, those produced by condensing an aromatic polycarboxylic acid such as phthalic acid, terephthalic acid, or isophthalic acid with a polyhydric alcohol, or those produced from polyethylene terephthalate-based waste can be used.

Of these, preferred polyols are
Grade amino group-containing polyol, polyester polyol,
An oxyalkylated polyhydric alcohol and a mixed system thereof, particularly a mixed system containing 10% by weight or more of an aromatic polyester polyol are preferably used. In the present invention, the polyol used has an average hydroxyl value of 20.
Those having 0 to 600 are particularly preferably used.

The polyisocyanate used in the present invention may be any known organic polyisocyanate without any problem.
For example, toluene diisocyanate, diphenylmethane-
4,4′-diisocyanate, aromatic polyisocyanate such as polymerized isocyanate thereof, aliphatic polyisocyanate such as hexamethylene diisocyanate, alicyclic polyisocyanate such as isophorone diisocyanate,
Also, a toluene diisocyanate prepolymer obtained by reacting them with a polyol, diphenylmethane-4,4'-
Examples include isocyanate-terminated prepolymers such as diisocyanate prepolymers, modified isocyanates such as carbodiimide-modified, and mixed polyisocyanates thereof, and more preferably diphenylmethane-4,
It is a mixed polyisocyanate (crude MDI) of 4'-diisocyanate and its polymerized isocyanate.

In the present invention, the mixing ratio between the polyol and the polyisocyanate is usually from 130 to 350, preferably from 180 to 250, as an isocyanate index.
It is. The mixing method can be performed by a commonly used spray foaming machine. The spray foaming machine may be either an external mixing type or an internal mixing type.

As the blowing agent used in the present invention, known halogenated methanes such as methylene chloride and carbon tetrachloride, halogenated hydrocarbons such as halogenated ethanes, and hydrofluorocarbons can be used. Of which are dichlorotrifluoroethane (HCFC-123) and dichloromonofluoroethane (HCFC-141b)
And hydrofluorocarbon compounds such as 1,1,1,3,3-pentafluoropentane (HFC-245fa) and tetrafluoroethane (HFC-134a). Furthermore, hydrocarbons such as cyclopentane, normal pentane, and isopentane can be used, and only water can be used as a foaming agent.

The amount of water used in the present invention is 0.5 parts by weight or more, preferably 2.0 to 10.0 parts by weight, based on 100 parts by weight of the polyol. The proportions of water and chlorofluorocarbon are not generally determined, but are determined according to the desired density and physical properties of the foam. The amount of these foaming agents is determined according to the required application and physical properties, but the density of the obtained foam is usually 10 to 70 kg / m ³ , preferably 15 to 5 kg / m ³ .
It is selected to be 0 kg / m ³ .

In the present invention, an organic silicon compound is used as a foam stabilizer. The number of parts used is not particularly limited, but is 0.1 to 5 parts by weight per 100 parts by weight of the polyol.
Parts by weight are desirable.

If necessary, a coloring agent, a flame retardant, an antioxidant and other known additives can be used. The types and amounts of these additives can be used in a range usually used as long as they do not deviate from known types and procedures.

[0038]

EXAMPLES The present invention will be described below based on examples and comparative examples, but the present invention is not limited to these examples. The following formulation was used for the hard isocyanurate spray foam system.

A. Formulation (parts by weight) Polyol 1) 80.0 Polyol 2) 20.0 Foam stabilizer 3) 2.0 Water 1.0 HCFC-141b 27.0 TCPP 4) 25.0 Catalyst-A 5) Change Catalyst-B 6) Changed potassium octylate 7) Changed lead octylate 8) 0.3 Amine compound 9) Changed isocyanate 10) Index = 200 1) Waste PET-based polyol (Oxol Co., Terol 250) OH value = 250mgKOH / g 2) Amine polyol (450 ED, manufactured by Asahi Ohlin Co., Ltd.) OH value = 450 mgKOH / g 3) Silicone surfactant (L-5420, manufactured by Nippon Unicar) 4) Flame retardant: trischloropropyl phosphate (Akzo Kashima, Filol PCF) 5) Tosoh Corporation: Triethylenediamine 6) Tosoh Corporation: Pentamethyl Triamine 7) diethylene glycol solution (70 wt% of potassium octoate) 8) Nihon Kagaku Sangyo Co., Ltd., Nikka Ok Chicks lead 9) Description of catalytic symbols in Table D-230: San Techno Chemical Co., Jeffamine D-230

[0040]

Embedded image

(In the formula, a1 is 2-3 and the molecular weight is about 230.) D-400: Jeffamine D-400, manufactured by San Techno Chemical Co.

[0042]

Embedded image

(In the formula, a2 is 5 to 6 and the molecular weight is about 400.) T-403: Jeffamine T-403 manufactured by San Techno Chemical Co.

[0044]

Embedded image

Wherein the molecular weight is about 440. EGDA: 4,7-dioxadecane-1,10-diamine

[0046]

Embedded image

BDDA: 4,9-dioxadodecane
1,12-diamine

[0048]

Embedded image

EDA: ethylenediamine AEEA: aminoethylethanolamine PDA: 1,3-propanediamine TEDA: manufactured by Tosoh Corporation, triethylenediamine DT: manufactured by Tosoh Corporation, pentamethyldiethylenetriamine 10) Isocyanate crude MDI NCO concentration = 31.0 % (Made by Nippon Polyurethanes, MR
-200) b. Foaming conditions Spray foaming machine: H-2000 manufactured by Gasmer Co., Ltd. Raw material liquid temperature: 40 ± 1 ° C Substrate: slate plate, veneer plate (40 × 60 cm) Substrate surface temperature: 0 ° C. c. Measurement items The following items were measured. Reactivity Cream time (hereinafter abbreviated as CT): Forming start time (second).

Rise time (hereinafter abbreviated as RT): The time (second) when the foam reaches the maximum foaming height.

Evaluation of foam physical properties Adhesiveness The foams sprayed and foamed on the slate plate were observed and ranked on a five-point scale.

1: Very strong adhesion 2: Strong 3: Normal 4: Weak 5: Remarkably weak, and foam peeling is also observed. Foam density 5 × from foam foamed free and foam foamed on plywood A test piece having a size of 5 × 5 cm was cut out and the density was measured.

Evaluation of dimensional stability 5 × 5 × 5 from foam blown and foamed on plywood
A test piece having a size of cm was cut out at 50 ° C and -2.
The dimensional change when held at 0 ° C. for 45 hours was evaluated.

Evaluation of Formability The foam sprayed on the slate plate was observed for cell roughness and voids, and ranked on a five-point scale.

1. Almost none 2. Small 3. Medium 4. Big 5. Very large Example 1 Jeffamine D230 as initial foam improver5.
The data were obtained when 0 pbw was used and no foaming catalyst was used. The results are shown in Table 1.

[0056]

[Table 1]

Example 2 Jeffamine D230 was used as an initial foam improver.
This is foaming data when 0 pbw was used and DT was used at 0.8 pbw as a foaming catalyst. The results are shown in Table 1.

Example 3 Jeffamine D400 was used as an initial foam improver.
This is foaming data when 0 pbw was used and DT was used at 0.8 pbw as a foaming catalyst. The results are shown in Table 1.

COMPARATIVE EXAMPLE 1 An ordinary catalyst without using an initial foaming property improver (using 5.0 pbw of potassium octylate as a resin-forming catalyst, 1.7 pbw of TEDA and 1.0 pbw of DT as a foaming catalyst) This is data obtained when foaming was performed using only the foam, and the results are shown in Table 1.

Example 4 Jeffamine T403 was used as an initial foam improver.
This is foaming data when 0 pbw was used and DT was used at 0.8 pbw as a foaming catalyst. The results are shown in Table 2.

[0061]

[Table 2]

Example 5 Foaming data when EGDA was used as an initial foamability improver at 5.0 pbw and DT was used at 0.8 pbw as a foaming catalyst. The results are shown in Table 2. Was.

Example 6 This is foaming data when BDDA was used as an initial foaming improver at 5.0 pbw and DT was used at 0.8 pbw as a foaming catalyst. The results are shown in Table 2. Was.

Example 7 Foaming data when AEEA was used at 1.8 pbw as an initial foaming property improving agent and DT was used at 0.8 pbw as a foaming catalyst, and the results are shown in Table 3. Was.

[0065]

[Table 3]

Example 8 Foaming data for foaming when 1.3 pbw of PDA was used as an initial foamability improver and 0.8 pbw of DT as a foaming catalyst. The results are shown in Table 3. Was.

Example 9 Foaming data for foaming when 1.0 pbw of EDA was used as an initial foamability improver and 0.8 pbw of DT as a foaming catalyst. The results are shown in Table 3. Was.

Example 10 Jeffamine D230 was used as an initial foam improver.
The foaming data was obtained when 5 pbw and 0.5 pbw of EDA were used at the same time and DT of 0.8 pbw was used as a foaming catalyst. The results are shown in Table 4.

[0069]

[Table 4]

COMPARATIVE EXAMPLE 2 An ordinary catalyst without using an initial foaming property improving agent (using 5.0 pbw of potassium octylate as a resin-forming catalyst, 2.5 pbw of TEDA, and 1.5 pbw of DT as a foaming catalyst) The foaming data was obtained when foaming was performed only with the amine catalyst and the amount of the amine catalyst used was increased from that in Comparative Example 1. The results are shown in Table 4.

As is clear from Tables 1 to 4, Comparative Example 1
In the case of (1), that is, when the initial foamability improving agent of the present invention is not used, the CT exceeds 1 second, and liquid dripping occurs. In addition, the adhesiveness is poor, and it occurs until the foam is peeled off. Even when the amounts of the amine catalyst and the foaming catalyst used were increased, no improvement was observed as compared with Comparative Example 1 as shown in Comparative Example 2. On the other hand, as shown in Examples 1 to 10, it is understood that the use of the initial foamability improver of the present invention shortens the CT to about 0.8 seconds and eliminates dripping. Will. In addition, the adhesiveness becomes very strong, and a low-density foam is obtained in each case. The values of the dimensional stability of the foam were the same as those of Comparative Examples 1 and 2, and it can be seen that the values did not deteriorate. When the foaming catalyst is not used, that is, the initial foaming property is also improved in Example 1, but when the foaming catalyst is used in combination as in Examples 2 to 9, the initial foaming property is further improved. You can see that.
Further, in Example 10, the data when ethylene diamine and Jeffamine D230 were used as the initial foaming property improver and DT was used as the foaming catalyst were shown.
This shows data comparable to Example 9. In conclusion, the use of the initial foamability improver of the present invention makes it possible to improve the decrease in initial foamability, which was a conventional problem in the production of a rigid isocyanurate spray foam, and the problems such as sagging of the foam and deterioration of workability are solved. Can contribute. Furthermore, the initial foamability improving agent of the present invention can reduce the density of the foam and improve the adhesiveness.

[0072]

According to the present invention, it has been difficult until now.
Improvements in initial foamability in hard isocyanurate spray formulations can be made. In particular, it is possible to improve the foam stability and moldability during foaming during spraying at low temperatures in winter, and achieve a low density foam.
Good rigid isocyanurate spray foam can be produced.

[0073]

Continued on the front page (51) Int.Cl. ⁶ Identification code FI C08L 75:00

Claims (5)

[Claims] 1. A catalyst comprising a polyol and a polyisocyanate,
In a method for producing a rigid isocyanurate spray foam by reacting in the presence of a foaming agent, a foam stabilizer and, if necessary, other auxiliaries, an initial foamability improving agent represented by the following general formulas (1) to (5). 1 selected from amine compounds
A method for producing a rigid isocyanurate spray foam, comprising using one or more amine compounds. Embedded image (Wherein, R1 to R4 each independently represent a lower alkyl group having 1 to 4 carbon atoms or hydrogen, and a represents a number of 1 to 50). (Wherein, R5 to R10 each independently represent a lower alkyl group having 1 to 4 carbon atoms or hydrogen, and x, y, and z each independently represent a number in the range of 1 to 50. A represents glycerin or (This represents trimethylolpropane.) (In the formula, b represents an integer in the range of 2 to 8.) (Wherein, R11 and R12 each independently represent a lower alkyl group having 1 to 4 carbon atoms or hydrogen, A represents an oxygen or nitrogen group, and R13 has no bonding group when A is an oxygen group;
When A is a nitrogen group, it represents hydrogen. B represents hydrogen when A is an oxygen group, and represents a hydroxyalkyl group when A is a nitrogen group. c represents an integer in the range of 1 to 3. ) (In the formula, d represents an integer of 2 to 12.) 2. The compound of the general formula (1) as an initial foaming property improving agent
One or two selected from amine compounds represented by (5)
The method according to claim 1, wherein a mixture of at least one kind of amine compound and a foaming catalyst is used. 3. An initial foaming property improving agent represented by the following general formula (1):
One or two selected from amine compounds represented by (5)
The method according to claim 1, wherein a mixture of at least one kind of amine compound, foaming catalyst and ethylenediamine is used. 4. The process according to claim 2, wherein the foaming catalyst is pentamethyldiethylenetriamine and / or bis (dimethylaminoethyl) ether. 5. An isocyanate index of 130 to 3
The method according to any one of claims 1 to 4, wherein the number is 50.