JP2003201330A - Urethane-modified polyisocyanurate foam - Google Patents

Abstract

(57) [Problem] To solve the problems of polyisocyanurate foams caused by carbon dioxide gas foaming, it is necessary to obtain high foaming ratio foams with improved foam communication, that is, improved shrinkage, and flame retardancy. It is necessary to solve both the problems of heat resistance and heat resistance at the same time. SOLUTION: By using a polyisocyanate compound component (A), a polyol component (B), and a benzylic ether type phenol resin as the polyol component, flame retardancy and heat resistance are improved, and water ( C), two or more kinds of foam stabilizers (D) of surfactants having different surface tensions, the control of cell size is enabled by the foam stabilizers, and the reaction is carried out in the presence of a trimerization catalyst (E). And a urethane-modified polyisocyanurate foam.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to chlorofluorocarbon (C
FC) and hydrochlorofluorocarbon (HCFC) as a foaming agent, and relates to a urethane-modified polyisocyanurate foam having a high expansion ratio, which is excellent in flame retardancy, heat resistance, and low smoke generation.

[0002]

BACKGROUND OF THE INVENTION In the polyurethane and polyisocyanurate foam industry, the use of CFCs, which have been used as useful and effective blowing agents, was banned since 1995 due to ozone depletion problems, and is an alternative to CFCs. HCFC with much lower ozone depleting activity is 200
It is banned from three years. Therefore, HCF
A hydrofluorocarbon (H
Various foaming agents such as FC), hydrocarbons (pentane, etc.) and carbon dioxide are being studied.

Presently, urethane type foam (hereinafter referred to as PU
In the field of heat-insulating siding and panels using R) as the core material, switching from HCFC foaming to carbon dioxide gas foaming is progressing, and it is said to be almost completed.

However, in the case of a polyisocyanurate type foam (hereinafter referred to as PIR type) excellent in flame retardancy and heat resistance, it is said that when the carbon dioxide gas foaming method is applied, the adhesion to the face material is insufficient. In addition to problems, flame retardancy and heat resistance decrease,
In particular, there is a problem of shrinkage (deformation) with time, and switching to carbon dioxide gas foaming does not proceed as smoothly as in the case of the PUR system. Generally, in the carbon dioxide foaming method, the foam shrinks (deforms) with time.
It is said to cause The cause is that carbon dioxide gas escapes quickly from the inside of the foam cell.

Adiabatic siding whose core material is PUR,
In the panel field, the switch to carbon dioxide foaming has almost been completed by reducing the closed cell ratio (making the foams continuous) as a means of solving shrinkage (deformation) with time. For example, a method in which a high-molecular weight polyol and a low-molecular weight polyol are combined to form a continuous foam to obtain a low-density foam that does not shrink.

[0006]

In the field of heat-insulating siding and panels using a PIR core as a core material, a method using a special polyol is used as a method of preventing shrinkage (deformation) due to foam communication (JP-A-10-231345). , There is a method of obtaining a foam having a relatively low density by using a trimerization catalyst and a carbodiimidization catalyst in combination (Patent No. 2972523), but there is a new method of lowering the adhesiveness of the foam to the face material, flame retardancy and heat resistance PIR caused by carbon dioxide gas foaming
It is difficult to put the system into practical use.

In order to put the PIR system by carbon dioxide gas foaming into practical use, it is necessary to simultaneously solve the problems of continuous foaming, that is, improvement of shrinkability and improvement of flame retardancy and heat resistance.

[0008]

[Means for Solving the Problems] The inventors of the present invention have eagerly addressed the problem of simultaneously improving the shrinkability of a PIR system by carbon dioxide gas foaming and the improvement of flame retardancy and heat resistance. In the following, the above problems were solved all at once by finding a method of applying (hereinafter, referred to as BEP) to a PIR system and a unique method that makes it possible to freely adjust the cell size.

Specifically, as the polyol component, BEP
The flame retardancy and heat resistance are improved by using, and the cell size is controlled by mixing surfactants having different properties in an appropriate ratio. For example, the foam stabilizer (1) may be a silicone-based surfactant, and the foam stabilizer (2) may be dimethyl silicone oil. More specifically, the present invention relates to a polyisocyanate compound component (A) and a polyol component (B) [wherein the polyol component is a polyhydric alcohol or its alkylene oxide adduct 20 to 100 relative to 100 parts by weight of a benzylic ether type phenol resin]. A modified phenolic resin obtained by adding 1 part by weight and heating under reduced pressure (hereinafter referred to as modified BEP) is included in an amount of 3% by weight or more based on the total resin content], water (C), different surface It is composed of a mixture of two or more kinds of silicone-based surfactants having a tension, in which the component having a higher surface tension has a surface tension of more than 22 dyne / cm, and the component having a lower surface tension is 22 dy.
A urethane-modified polyisocyanurate foam characterized by reacting a foam stabilizer (D) having a surface tension of ne / cm or less in the presence of a urethanization catalyst and / or a trimerization catalyst (E).

[0010]

DETAILED DESCRIPTION OF THE INVENTION The polyol component used in the present invention is a mixture of modified BEP and a polyol generally used in the production of urethane foams. That is, Japanese Patent Publication 7-3
JP-A No. 0155, the polyhydric alcohol or its alkylene oxide adduct 20 to 10 relative to 100 parts by weight of the benzylic ether type phenol resin.
Modified B produced by adding 0 parts by weight and heating under reduced pressure
It is constructed around the EP. As other polyols that can be used together, ethylene glycol, diethylene glycol, polyethylene glycol, propylene glycol, dipropylene glycol, polypropylene glycol, polytetramethylene glycol, 1,4-butanediol, etc., or one of these alkylene oxides or Two or more kinds of addition-functionalized difunctional polyols, trimethylolpropane, glycerin, etc., or addition-functionalized alkylene oxides of these trifunctional polyols, pentaerythritol, sorbitol, sugar, etc., or addition-polymerized alkylene oxides thereof. Functional polyols, other alkanolamines with addition polymerization of alkylene oxides, and aromatic polyester polyols and acrylic polyol resins. There, it alone or may be used as a mixture of two or more. The amount of the modified BEP used is appropriately 3.0% by weight or more based on the total resin content. If it is less than 3.0% by weight, flame retardancy, heat resistance and low smoke generation deteriorate.

As the polyisocyanate compound used in the present invention, those generally used for the production of urethane foams can be used, and there is no particular limitation, and m- or p-phenylene diisocyanate, p -Xylene diisocyanate, ethylene diisocyanate, tetramethylene-1,4-diisocyanate, hexamethylene-
1,6-diisocyanate, diphenylmethane-4,
4'-diisocyanate, 3,3'-dimethyl-diphenylmethane-4,4'-diisocyanate, 3,3-dichloro-4,4'-biphenylene diisocyanate or 1,5-naphthalene diisocyanate, 2,4- and 2,6-tolylene diisocyanate and mixtures thereof, crude tolylene diisocyanate, 4,4′-diphenylmethane diisocyanate, crude diphenylmethane diisocyanate and the like. These isocyanate compounds may be used alone or in admixture of two or more. The amount used is an equivalence ratio of isocyanate groups to active hydrogen in the polyol component mixture of 1.05 to 5.0, preferably 1.50 to 3.
The range is 0. If the equivalent ratio is less than 1.05,
Flame retardancy, heat resistance, and low smoke generation deteriorate, and when it exceeds 5.0, the brittleness of the foam increases and the adhesion to the face material deteriorates.

The foam stabilizer used in the present invention is a mixture of two or more kinds of silicone type surfactants having different surface tensions, and the component having the higher surface tension is 22dyne /
Those having a surface tension of cm or more are used. Generally, an organic polysiloxane copolymer, a polydimethylsiloxane polyalkylene oxide adduct, and a vinylsilane / polyoxyalkylene polyol compound used as a foam stabilizer during the production of urethane foam are suitable. The component having a lower surface tension is 22 dyne / cm or less, and dimethyl silicone oil is preferable.

As the organic polysiloxane copolymer, SH-190, SH-192, S manufactured by Toray Silicone Co., Ltd.
H-193, SH-194, M505, M507, M5
09, SRX253, L-5 made by Nippon Unicar Co., Ltd.
20, L-540, L-580, L-582, L-53
40, L-5410, L-5420, L-5470, S
There is Z-1127, TFA-4 made by Toshiba Silicone Co.
200, TFA4205, TFA7241, B-8404 and B-8017 manufactured by Gold Schmidt.

Examples of the dimethyl silicone oil include SH-200 manufactured by Toray Silicone Co., Ltd., TSF-451-5, TSF451-50 and TSF4 manufactured by Toshiba Silicone Co., Ltd.
There are 05 etc.

The mixing ratio of the component having the higher surface tension and the component having the lower surface tension is 100 parts by weight: 0.5 to 50.
A proportion of parts by weight is suitable. If the amount is less than 0.5 parts by weight, no effect is observed and shrinkage occurs. On the other hand, when the amount is more than 50 parts by weight, the foam breaking effect becomes large and a good foam cannot be obtained. The amount of the foam stabilizer (D), which is a mixture of two or more kinds of silicone-based surfactants having different surface tensions, is 0.
5 to 10 parts by weight is suitable.

As the catalyst for carrying out the urethanization reaction, those generally known as urethanization catalysts can be used. For example, N, N, N ', N'-tetramethylethylenediamine, N, N, N', N'-tetramethylpropane-1,3-diamine, N, N, N ', N'.
-Tetramethylhexene-1,6-diamine, N, N,
N ′, N ″, N ″ -pentamethyldiethylenetriamine, N, N-dicyclohexylmethylamine, bis (N, N-dimethylaminoethylpiperazyl) ethane,
Tertiary amines such as N, N ′, N ″ tris (diethylaminopropyl) hexahydrotriazine and dibutyltin dilaurate, dibutyltin diacetate, etc. are used alone,
Alternatively, they can be used in combination with each other.

As the isocyanate trimerization catalyst used in the present invention, the isocyanate trimerization catalyst which has been conventionally used for the production of polyisocyanurate resin or the like can be used. The following can be mentioned as specific examples of the isocyanate trimerization catalyst. In the organometallic salt system,
Examples include potassium acetate, potassium octenoate, and iron oxalate. Examples of the tertiary amine salt include 2,4,6-tris (dimethylaminomethyl) -phenol and N, N ′, N ″ -tris (dimethylaminopropyl) hexahydrotriazine.

The amount of the urethanization catalyst and trimerization catalyst (E) used in the present invention is the same as that of the polyol component (B) 1
The amount is 0.3 to 15 parts by weight, preferably 0.70 to 10 parts by weight, based on 00 parts by weight.

The water (C) used in the present invention generates carbon dioxide by the reaction with the polyisocyanate compound and acts as a foaming agent. The amount of water used is determined by the density of the desired foam, and the polyol component (B)
2 to 30 parts by weight is suitable for 100 parts by weight. If the amount of water used is less than 2 parts by weight, the density of the foam will be too high, and if it exceeds 30 parts by weight, the mechanical strength will be reduced and the product will not be usable.

In the present invention, a crosslinking agent and a viscosity reducing agent may be used if necessary. As the cross-linking agent, ethylene glycol, propylene glycol, 1,4-butanediol, 1,6-hexanediol, diethylene glycol, triethylene glycol, triethanolamine, ethylenediamine or the like can be used alone or in combination.
As the viscosity reducer, a room-temperature liquid organic compound such as nitrogen-containing, sulfur-containing, phosphorus-based, ether-based, hydrocarbon-based, ester-based, carbonate-based can be used alone or in combination. These additives and other additives are the polyol component (B).
It may be mixed in advance with a mixture containing, or may be added during the reaction.

At the time of producing the polyisocyanurate foam of the present invention, it is possible to use a high-pressure foaming machine, a medium-pressure foaming machine, a low-pressure foaming machine, or the like for factory production of boards, panels, siding, or on-site foaming. Is.

[0022]

EXAMPLES The present invention will be specifically described below with reference to Examples and Comparative Examples. Display of Examples and Comparative Examples, measurement method,
The method for preparing the sample is as follows. [%] Is based on weight. The density was measured according to JIS A-9511. The closed cell ratio was measured by ASTM-DT2856.
The flame retardancy test was conducted by JI
Surface testing was performed according to SA-1321.

In Examples and Comparative Examples, a compounding solution was prepared according to the compounding recipe (hereinafter referred to as a predetermined compounding recipe) shown in Table 1, mixed and stirred with a high speed stirrer at 4000 rpm, and then an aluminum box was used. To produce a foam. The foam was obtained by heating an aluminum box of 250 mm × 250 mm × 250 mm to 40 ° C. and free-foaming. The core portion of the above free-foamed foam was cut out and used for the test.

The raw materials used are as follows. Modified BEP: Modified phenol resin (Hodogaya Chemical Co., Ltd., BEP2100M, OH value 620) Other polyol 1: Aromatic polyester polyol (Toho Rika Co., Ltd., PL-135, OH value 200) Other polyol 2 : Glycerin type polyether polyol (manufactured by Takeda Pharmaceutical Co., Ltd., MF-78, OH value 35) TEP: Triethyl phosphate (manufactured by Bayer, flame retardant) Trimerization catalyst: potassium octenoate type (PELRON C
o. Foam stabilizer (1): Organic polysiloxane copolymer (manufactured by Toray Silicone Co., Ltd., SH-190, surface tension 23.5 dy)
ne / cm) Foam stabilizer (2): dimethyl silicone oil (manufactured by Toshiba Silicone Co., Ltd., TSF-451-100, surface tension 2)
0.8 dyne / cm) Isocyanate compound: crude diphenylmethane diisocyanate (manufactured by Nippon Polyurethane Industry Co., Ltd., MR-10)
0, NCO content rate 31.0%)

Example 1 A blended liquid was prepared according to a prescribed formulation, a foam was produced by a prescribed method, and the density and the closed cell ratio were measured. A-1 to 3 are compositions in which the compounding ratio of only the foam stabilizer (2) was changed. The weight ratio to the whole is 0.0
3, 0.06 and 0.12%. Table 1 shows the formulation and physical properties. From this result, it is understood that a high expansion ratio can be obtained, and the foaming ratio can be controlled by changing the type and the compounding ratio of the foam stabilizer, and the dimensional stability is excellent.

[0026]

[Table 1]

Example 2 A-2 of Example 1 was used, and a colored zinc steel sheet having a thickness of 0.35 mm was used as a double-sided material, and 200 mm × 100 mm × 25.
Table 2 shows the results obtained by preparing a test piece with a mold having a thickness of mm and performing a aging test under severe conditions. From the test results, it is stable at both high temperature and low temperature, and has sufficient performance for practical use.

[0028]

[Table 2]

Example 3 In order to verify the effect of the present invention from the viewpoint of heat resistance,
Table 3 shows the results obtained by performing a heat resistance test and measuring the volume change rate. As the test body, A-2 of Example 1 was used, and a sample was prepared by a predetermined method. From these results, it is understood that the effect of adding BEP is remarkable especially under high temperature conditions.

[0030]

[Table 3]

Example 4 Table 4 shows the results of the flame retardancy test. Example 1A-
A flame retardancy test was carried out using a foam prepared from the formulation of No. 2 by a predetermined method. The test piece is 220 mm x 220 m
It is m × 25 mm. From this result, it is understood that the effect of the present invention is also excellent in terms of flame retardancy.

[0032]

[Table 4]

Example 5 Table 5 shows the results of comparison of the effect of the present invention with the excellent product in the conventional HCFC foaming in the physical properties of the board, the flame retardancy test and the asphalt test. The formulation was according to A-1 of Example 1, and the production was performed on the board line. From this result, carbon dioxide foaming according to the present invention is as good as HCFC foaming,
It can be seen that it is practical and can exhibit excellent performance as a heat and waterproof board.

[0034]

[Table 5]

Example 6 The effects of the present invention were examined by a siding dimensional stability test and a flammability test. The results are shown in Table 6. The siding was composed of an aluminum foil of 20 μm, a PIR type of 9 mm, and a colored aluminum plate of 0.35 mm, and was manufactured by a continuous line. From this result, it is understood that the effect of the present invention is excellent also in siding. In addition, JIS A-1321
It was found that it corresponds to Class 2 flame-retardant based on, and it is understood that it is practically applicable.

[0036]

[Table 6]

[0037]

EFFECTS OF THE INVENTION According to the present invention, a low density urethane-modified polyisocyanurate foam (PIR type) having less shrinkage and good flame retardancy, heat resistance, adhesiveness, and reactivity without using CFC or HCFC. ) Has become possible.

   ─────────────────────────────────────────────────── ─── Continued front page    F-term (reference) 4J034 AA04 AA06 BA07 CA03 CA04                       CA05 CB02 CB03 CB04 CB05                       CB07 CC03 DA01 DB03 DB04                       DB05 DB07 DC01 DC02 DJ08                       HA01 HA07 HC01 HC02 HC03                       HC11 HC12 HC13 HC64 HC67                       HC68 HC71 HC73 KB03 KC17                       KD12 NA03 NA08 QB01 QC01                       RA10

Claims (5)

[Claims] 1. A polyisocyanate compound component (A),
Polyol component (B) (The polyol component is a polyhydric alcohol or its alkylene oxide adduct 20 to 100 parts by weight of the benzylic ether type phenol resin.
100 parts by weight is added, and the modified phenol resin obtained by heating under reduced pressure is contained in an amount of 3% by weight or more based on the total resin content), water (C), and a silicone-based surface active agent having different surface tensions. It is composed of a mixture of two or more kinds of agents, of which the higher surface tension component has a surface tension of more than 22 dyne / cm and the lower surface tension component is 2
Foam stabilizer (D) having a surface tension of 2 dyne / cm or less
Is reacted in the presence of a urethanization catalyst and / or a trimerization catalyst (E), a urethane-modified polyisocyanurate foam. 2. The foam has a density of 15 kg to 50 kg /
The urethane-modified polyisocyanurate foam according to claim 1, which is m ³ . 3. The urethane-modified polyisocyanurate foam according to claim 1, wherein the foam is a heat insulating and waterproof board. 4. The urethane-modified polyisocyanurate foam according to claim 1, wherein the foam is a panel core material. 5. The urethane-modified polyisocyanurate foam according to claim 1 or 2, wherein the foam is a core material for metal siding.