JPH11286530A - Production of urethane-modified polyisocyanurate foam - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing the subject foam, not causing shrinkage at ordinary temperature in heating and in moist heat even in the case of high foaming magnification without using a chlorofluorocarbon compound as a foaming agent by using water as a foaming agent. SOLUTION: This method for producing a urethane-modified polyisocyanurate foam comprises reacting (A) a polyisocyanate compound component with (B) a polyol component, (C) water and (D) a foam stabilizer comprising a mixture of two or more kinds of surfactants having different HLB values in the presence of (E) an isocyanate trimer catalyst. Furthermore, it is preferable that the component D is a silicone-based surfactant and (i) HLB value is >=22 in the component having higher HLB value and (ii) HLB value is <=22 in the component having lower HLB value and the component (ii) is used in an amount of 0.5-50 pts.wt. based on 100 pts.wt. component (i) and the component D is used in total amount of 0.5-10 pts.wt. based on 100 pts.wt. component B.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a method for producing a foam having a high expansion ratio, which does not use a chlorofluorocarbon compound as a foaming agent, and has improved shrinkage at normal temperature, hot and wet heat.

[0002]

2. Description of the Related Art A urethane-modified polyisocyanurate foam has been conventionally known as a heat insulating material having excellent flame retardancy, heat resistance and low smoke emission. In this case, the chlorofluorocarbon compound used as the foaming agent is required to be reduced or not used because of the problem of destruction of the ozone layer. For this reason, a production method using water as a foaming agent has been studied. By using a benzylic ether-type phenol resin as a polyol, a urethane-modified polyisocyanurate having characteristics of flame retardancy, heat resistance, and low smoke emission is provided. Although a foam was obtained (Japanese Patent Application Laid-Open No. 8-134169), the shrinkage of the foam at normal temperature, under heat, and under wet heat under high expansion ratio conditions was unresolved. On the other hand, in the case of phenolic urethane foam, as a method for improving the shrinkage of a foam having a high expansion ratio using water as a foam, there is a report using a silicone-based foam stabilizer (Japanese Patent Application Laid-Open No. 6-220153).

[0003]

When water is used as the blowing agent, the urea bonds are incorporated into the polymer skeleton in a large amount, which adversely affects the physical properties of the foam. Since it is necessary to further increase the amount of water to obtain a high expansion ratio, there are many problems to be solved in the case of a urethane-modified polyisocyanurate foam. During the production of foam, the isocyanate trimerization reaction, the carbon dioxide generation reaction of isocyanate and water, and the urethanation reaction proceed in parallel, so that optimal production conditions are minimized while minimizing adverse effects on the physical properties of the foam. There is the difficulty of having to establish. In particular, an effective countermeasure against foam shrinkage has not been found yet, and its improvement is strongly demanded. The present invention uses water as a blowing agent without using a chlorofluorocarbon compound, and maintains excellent characteristics of flame retardancy, heat resistance, and low smoke generation even when a high expansion ratio is used. It is another object of the present invention to provide a method for producing a urethane-modified polyisocyanurate foam which does not shrink when wet and heated.

[0004]

The present inventors have conducted intensive studies on a method for producing a urethane-modified polyisocyanurate foam having a high expansion ratio by using water as a foaming agent.
The present invention has been reached.

That is, the present invention relates to a foam stabilizer (D) comprising a mixture of two or more of a polyisocyanate compound component (A), a polyol component (B), water (C), and a surfactant having different HLB values. Is reacted in the presence of a trimerization catalyst (E) to produce a urethane-modified polyisocyanurate foam. Further, the present invention is a urethane-modified polyisocyanurate foam produced by this production method.

[0006] The invention is characterized by the use of a mixture of two or more surfactants having different HLB values. Among these surfactants, the component having a higher HLB value has an HLB value larger than 22, and the component having a lower HLB value has an HLB value of 22 or less. These different HLB
By combining a plurality of surfactants having different values, the continuity of the cells of the manufactured foam can be increased, and the cells can be made larger and the cell membrane can be made thicker. It is possible to produce a urethane-modified polyisocyanurate foam excellent in flame retardancy, heat resistance, and low smoke generation with almost no shrinkage at normal temperature, hot and wet heat. Regardless of whether a high-pressure foaming machine, a medium-pressure foaming machine or a low-pressure foaming machine is used in the production of a urethane-modified polyisocyanurate foam, these different HLBs are used.
By finely adjusting the mixing ratio of a plurality of surfactants having different values, it becomes possible to stably maintain the optimum production conditions.

[0007]

DETAILED DESCRIPTION OF THE INVENTION The polyol component used in the present invention is a mixture of polyols generally used for producing urethane foam. That is, ethylene glycol, diethylene glycol, polyethylene glycol, propylene glycol, dipropylene glycol, polypropylene glycol, polytetramethylene glycol, 1,4-
Butanediol or the like, or a bifunctional polyol obtained by addition-polymerizing one or more alkylene oxides thereto,
Trimethylolpropane, glycerin or the like, or a trifunctional polyol obtained by addition-polymerizing an alkylene oxide thereto, pentaerythritol, sorbitol, sugar, or the like, or a polyfunctional polyol obtained by addition-polymerizing an alkylene oxide thereto, or an alkylene oxide to an alkanolamine It is an addition-polymerized one, and further includes an aromatic polyester polyol, a phenol resin, a modified phenol resin, and an acrylic polyol resin, and these may be used alone or in combination of two or more.

As the polyisocyanate compound used in the present invention, those generally used for the production of urethane foams can be used, and are not particularly limited, and may be m- or p-phenylene diisocyanate, -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-naphthalenediisocyanate, 2,4- and 2,6-tolylene diisocyanate and mixtures thereof, crude tolylene diisocyanate Nart, 4,4'-
Diphenylmethane diisocyanate, crude diphenylmethane diisocyanate and the like. These isocyanate compounds are used alone or in combination of two or more. The amount used is in the range of 1.50 to 10.0, preferably 1.75 to 4.5, equivalent ratio of the isocyanate group to the active hydrogen in the polyol component mixture. The equivalent ratio is 1.50
If it is smaller, flame retardancy, heat resistance, and low smoke emission will deteriorate,
If it is larger than 10.0, the brittleness of the foam increases, and the adhesion to the face material deteriorates.

The foam stabilizer used in the present invention has different HL
A mixture of two or more surfactants having a B value,
Preferred are silicone-based surfactants. As the component having a higher HLB value, one having an HLB value larger than 22 is used, and an organic polysiloxane copolymer generally used as a foam stabilizer during the production of urethane foam,
Polydimethylsiloxane polyalkylene oxide adducts and vinylsilane / polyoxyalkylene polyol compounds are preferred. A component having a low HLB value has an HLB value of 2
Two or less are used, with dimethyl silicone oil being preferred.

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

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

The mixing ratio of the component having a higher HLB value to the component having a lower HLB value is 100 parts by weight: 0.5 to 50 parts by weight.
A proportion by weight is appropriate. If the amount is less than 0.5 part 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 appropriate amount of the foaming agent, which is a mixture of two or more surfactants having different HLB values, is 0.5 to 10 parts by weight based on 100 parts by weight of the polyol component (B).

As the isocyanate trimerization catalyst used in the present invention, an isocyanate trimerization catalyst conventionally used for production of polyisocyanurate resins and the like can be used.

Specific examples of the isocyanate trimerization catalyst include the following. Among the organic metal salts, there are potassium acetate, potassium octenoate, iron oxalate and the like. Tertiary amine salts include 2,4,6-tris (dimethylaminomethyl) -phenol, N, N ', N "-tris (dimethylaminopropyl) hexahydrotriazine and the like.

As a catalyst for performing a urethane modification reaction,
A catalyst generally known as a urethanization catalyst can be used in combination. 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, N, N' And tertiary amines such as N "(diethylaminopropyl) hexahydrotriazine and dibutyltin dilaurate, dibutyltin diacetate and the like can be used alone or in combination.

The amount of the isocyanate trimerization catalyst used in the present invention is 0.35 to 15 parts by weight, preferably 0.70 to 15 parts by weight, based on 100 parts by weight of the polyol component (B).
10 parts by weight.

The water used in the present invention reacts with the polyisocyanate compound to generate carbon dioxide and act as a blowing agent. The amount of the water used is determined by the density of the target foam, and the amount of the polyol component (B) 100
A suitable amount is 2 to 30 parts by weight based on parts by weight. If the amount of water used is less than 2 parts by weight, the density of the foam becomes too high, and if it exceeds 30 parts by weight, the mechanical strength is reduced and the use cannot be tolerated.

In the present invention, a flame retardant, a crosslinking agent and a viscosity reducing agent can be used as required. As a flame retardant,
Triphenyl phosphate, tricresyl phosphate, tris chlorophosphate, tris-β-chloropropyl phosphate, tris-β-chloroethyl phosphate, trimethyl phosphate, triethyl phosphate, tributyl phosphate can be used alone or in combination. As the crosslinking agent, ethylene glycol, propylene glycol, 1,4-butanediol, 1,6-hexanediol, diethylene glycol, triethylene glycol, triethanolamine, ethylenediamine, and the like can be used alone or in combination. Nitrogen-containing, sulfur-containing, ether-based, phosphorus-based, halogen-based, hydrocarbon-based,
Room-temperature liquid organic compounds such as esters and carbonates can be used alone or in combination. These additives and other additives may be mixed in advance with the mixture containing the polyol component (B), or may be added during the reaction.

In the production method of the present invention, a mixture of a polyol component (B), water (C), a foam stabilizer (D), and an isocyanate trimerization catalyst (E) is prepared in advance as a mixing order of each component. In advance, a method of mixing with the polyisocyanate compound (A) at the time of the reaction, a mixture of the polyol component (B), water (C), and the foam stabilizer (D) are prepared in advance, and the polyisocyanate compound component at the time of the reaction. (A) and a method of mixing with the isocyanate trimerization catalyst (E), a mixture of the polyol component (B), water (C) and the isocyanate trimerization catalyst (E) is prepared in advance, and the polyisocyanate is used during the reaction. A method of mixing with the compound component (A) and the foam stabilizer (D), or a mixture of the polyol component (B) and water (C) is prepared in advance, and the polyisocyanate is used during the reaction. DOO compound component (A),
A method of mixing the foam stabilizer (D) with the isocyanate trimerization catalyst (E) can be adopted.

In producing the urethane-modified polyisocyanurate foam of the present invention, factory production and on-site foaming can be performed using a high-pressure foaming machine, a medium-pressure foaming machine, a low-pressure foaming machine, or the like.

[0021]

The present invention will be specifically described below with reference to examples and comparative examples. Parts and% are based on weight. Density is J
Measured according to IS A-9514. The shrinkage test at room temperature, under heat and under wet heat was performed by leaving test specimens of 50 × 50 × 50 mm under the conditions of 25 ° C., 90 ° C., 70 ° C. × 95% RH for 48 hours, respectively, and judging by their dimensional change rates. did.

Example 1 PL-107 (manufactured by Toho Rika Co., Ltd., aromatic polyester polyol, OH value: 19)
0) 70 parts, SOR-220 (Takeda Pharmaceutical Co., Ltd.)
Sorbitol polyol, OH value 200)
Parts, 10 parts of MF-78 (manufactured by Takeda Pharmaceutical Co., Ltd., glycerin-based polyol, OH value: 37) and tris (monomethyl-2-chloropropyl) phosphate (manufactured by Daihachi Chemical Co., Ltd., flame retardant) 15 parts, 1.5 parts of SH-193 (manufactured by Toray Dow Silicone Co., Ltd., foam stabilizer), TSF45
0.07 parts of 1-50 (manufactured by Toshiba Silicone Co., Ltd., dimethyl silicone oil), 7 parts of water, PELCAT95
40 (manufactured by PELRON Co., trimerization catalyst) in 3 parts,
One part of TOYOCAT DT (manufactured by Tosoh Corporation, urethanization catalyst) was mixed, and MR-100 (manufactured by Nippon Polyurethane Industry Co., Ltd., crude diphenylmethane diisocyanate,
385 parts (NCO content: 31.0%) was added and stirred, and the mixture was transferred to a 1-liter paper cup for foaming. The obtained foam has a good foam state and a density of 25.4 kg.
/ M ³ , shrinkage at room temperature, under heat and under heat and humidity was extremely small.

Examples 2 to 5 Various polyols, a foam stabilizer and dimethyl silicone oil were mixed, and foaming was carried out in the same manner as in Example 1. [Table-
1].

[0024]

[Table-1]

The raw materials used are specified below. BEP: Modified phenolic resin (Hodogaya Chemical Industry Co., Ltd.)
PL-107: aromatic polyester polyol (manufactured by Toho Rika Co., Ltd., OH value 190) Terol 236: aromatic polyester polyol (O)
xid Co. OH value: 245) SOR-220: propylene oxide adduct of sorbitol (manufactured by Takeda Pharmaceutical Co., Ltd., OH value: 200) MF-78: glycerin-based ethylene / propylene oxide adduct (manufactured by Takeda Pharmaceutical Co., Ltd.) OH value 37) TMCPP: Tris (monomethyl-2-chloropropyl)
Phosphate (flame retardant manufactured by Daihachi Chemical Co., Ltd.) SH-193: Foam stabilizer (Dow Silicone Toray Co., Ltd.)
TFA4205: foam stabilizer (manufactured by Toshiba Silicone Co., Ltd.) TSF451-50: dimethyl silicone oil (manufactured by Toshiba Silicone Co., Ltd.) PELCAT9540: potassium octenoate-based trimerization catalyst (manufactured by PELRON Co.) TOYOCAT DT: urethane conversion Catalyst (Tosoh Corporation)
MR-100: Crude diphenylmethane diisocyanate (Nippon Polyurethane Industry Co., Ltd., NCO content 31.
0%)

Comparative Example 1 A foam was prepared from the composition of Example 1 except that dimethyl silicone oil was omitted. Although the obtained foam had a good foam state, it had a very large shrinkage at normal temperature, hot and wet heat.

Comparative Example 2 In the composition of Example 1, the content of dimethyl silicone oil was
When the foam was prepared in an amount of 60 parts by weight with respect to 0 parts by weight, a foam breaking phenomenon was caused, resulting in a foam having a very high density of 52.3 kg / m ^3, and a foam having a high expansion ratio was obtained. Did not.

[0028]

As described above, according to the present invention,
Without using a haloalkane-based blowing agent that causes depletion of the ozone layer, two or more foam stabilizers are used in combination, and only carbon dioxide foaming using water is used. A production method for obtaining a foam having an expansion ratio was established.

Continued on the front page (51) Int.Cl. ⁶ Identification code FI C08J 9/02 CFF C08J 9/02 CFF C08L 75/04 C08L 75/04 // C08L 83/04 C08L 83/04 (C08G 18/48 101: 00)

Claims (10)

[Claims] 1. A polyisocyanate compound component (A),
Reacting a foam stabilizer (D) comprising a mixture of two or more of a polyol component (B), water (C), and a surfactant having different HLB values in the presence of an isocyanate trimerization catalyst (E). A method for producing a urethane-modified polyisocyanurate foam. 2. The method for producing a urethane-modified polyisocyanurate foam according to claim 1, wherein at least two of the surfactants having different HLB values are silicone-based surfactants. 3. Among the surfactants having different HLB values, the component having a higher HLB value has an HLB value larger than 22, and the component having a lower HLB value has an HLB value of 22.
3. The method according to claim 1, wherein:
A method for producing the urethane-modified polyisocyanurate foam according to the above. 4. The urethane according to claim 1, wherein the component having an HLB value larger than 22 is an organic polysiloxane copolymer, and the component having an HLB value of 22 or less is dimethyl silicone oil. A method for producing a modified polyisocyanurate foam. 5. The urethane-modified polyisocyanurate foam according to claim 1, wherein a high-pressure foaming machine, a medium-pressure foaming machine or a low-pressure foaming machine is used when producing the urethane-modified polyisocyanurate foam. How to make the body. 6. The polyol component (B) in which the mixing ratio of the foam stabilizer is 0.5 to 50 parts by weight of the component having a lower HLB value relative to 100 parts by weight of the component having a higher HLB value. 0.5 to 100 parts by weight of the foam stabilizer in total
The method for producing a urethane-modified polyisocyanurate foam according to claim 1, wherein 10 parts by weight are used. 7. An equivalent ratio of an isocyanate group of the polyisocyanate compound component (A), a polyol component (B) and water (C) to active hydrogen of 1.50 to 10.
The method for producing a urethane-modified polyisocyanurate foam according to claim 1, which is 0. 8. The isocyanate trimerization catalyst (E) is used in an amount of from 0.35 to 15 parts by weight based on 100 parts by weight of the polyol component (B).
The method for producing a urethane-modified polyisocyanurate foam according to claim 1, which uses parts by weight. 9. Water (C) is added to polyol component (B) 100
The method for producing a urethane-modified polyisocyanurate foam according to claim 1, which is used in an amount of 2 to 30 parts by weight based on parts by weight. 10. Polyisocyanate compound component (A), polyol component (B), water (C), different HL
A urethane-modified polyisocyanurate foam produced by reacting a foam stabilizer (D) comprising a mixture of two or more surfactants having a B value in the presence of an isocyanate trimerization catalyst (E).