JP2002161122A - Flame-retardant foam - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a flame-retardant foam of which the flame retardance can be improved further and which is excellent in rigidity and in other properties. SOLUTION: This flame-retardant foam is continuously formed by reacting an organic polyisocyanate component with a polyol component. Alkylene oxide in an amount of 3.0-5.0 mol is added to a polynuclear phenolic compound obtained from heavy oil or pitch to make a phenol resin and a blend of the phenol resin with an aromatic polyester polyol in a weight ratio range of 30/70-70/30 is used as the polyol component and an equivalent ratio of isocyanate groups/hydroxyl groups is kept in a range of 3.0-5.0.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flame-retardant foam, and is particularly suitable as a heat insulating material for buildings such as ceilings, floors and walls.

[0002]

2. Description of the Related Art Foams such as rigid urethane foams and polystyrene foams are widely used for heat insulation of ceilings, floors, walls and the like as architectural heat insulating materials because of their excellent heat insulating properties. However, when a foam such as a rigid urethane foam or a polystyrene foam is used as a heat insulating material, there are the following problems. These foams are easily combustible and their use is restricted in public facilities, fire protection and semi-fire protection areas by building regulations.

[0003] In addition, due to the recent revision of the Building Standard Law, a heat generation test method has been introduced for heat insulating materials, and the evaluation method of flame retardancy has been greatly changed.

Furthermore, in recent years, it is necessary to consider evacuation guidance for vulnerable people such as the elderly living in houses at the time of fire.
Therefore, in order to solve these problems, one of the characteristics required for a foam used as a heat insulating material or the like is to improve the flame retardancy.

For this reason, phenol foams, polyisocyanurate foams, polycarbodiimide foams, polyimide foams and the like have been developed in place of foams such as rigid urethane foams and polystyrene foams.

Japanese Patent Application Laid-Open No. 2000-1599 discloses that a highly reactive modified phenol resin obtained based on heavy oils or pitches is used, and is obtained from polyols, isocyanates, blowing agents, and catalysts. It is said that a flame-retardant foam can be obtained by the resin.

[0007]

However, although all foams have improved flame retardancy as compared with the conventional foams, they are still insufficient and need to be further improved in flame retardancy. Further, in the case of phenol foam, there are problems of formaldehyde generation and rust generation, and in the case of polyisocyanurate foam, there is a problem that it is brittle and lacks rigidity and breaks during construction. Further, in the case of a highly reactive modified phenol resin, there is a problem that when it is solid at ordinary temperature and its viscosity is reduced by using a diluent, foaming characteristics and flame retardancy are reduced. The present invention has been made in view of the problems of the related art, and aims to provide a flame-retardant foam that can further improve the flame retardancy and is excellent in other characteristics such as rigidity. Things.

[0008]

Means for Solving the Problems In order to solve the above-mentioned problems, the present inventors have conducted intensive studies and experiments, and as a result, an organic polyisocyanate component and a polyol component were used as main raw materials, and a foaming agent and a catalyst were used. As a polyol component of a foam produced by blending, a high-reactivity modified phenol resin obtained based on heavy oils or pitches is added with alkylene oxide to terminal OH groups of a polynuclear phenol. By using a combination of a polyol and an aromatic polyester polyol, it was found that a flame-retardant foam having flame retardancy was obtained by making use of the rigidity of the rigid polyurethane foam, and the present invention was completed. is there.

That is, in order to solve the problems of the above prior art, the flame-retardant foam according to claim 1 of the present invention comprises:
The reaction between the organic polyisocyanate component and the polyol component is a flame-retardant foam which is continuously foamed and molded, wherein the polyol component is obtained by using a heavy oil or a phenol polynuclear obtained based on pitches with an alkylene oxide. 3.0 to 5.0 moles are added to form a phenol resin, and the weight ratio of the phenol resin to the aromatic polyester polyol is from 30/70 to 70/30.
And the equivalent ratio of isocyanate group / hydroxyl group is in the range of 3.0 to 5.0.

According to this flame-retardant foam, the foam appearance is good and the properties such as the density are equal to or higher than those of the rigid polyurethane foam, and the flame penetration test (US Mining Bureau standard) and the heat generation test (quasi-noncombustible material test) Cone calorimeter test: ISO
(Measurement by 5660), etc., and is excellent in flame retardancy, and particularly suitable as a heat insulating material for buildings.

With the polyol component thus prepared, the viscosity can be adjusted to an appropriate level by diluting the solid phenol polynuclear at room temperature, and the foaming line used conventionally has excellent flame retardancy. Foam can be obtained.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the flame-retardant foam of the present invention will be described in detail below. This flame-retardant foam is a flame-retardant foam which is continuously foam-molded by a reaction between an organic polyisocyanate component and a polyol component, and is obtained based on heavy oil or pitch as the polyol component. 3.0 to 5.0 moles of an alkylene oxide is added to the resulting phenol polynuclear to form a phenol resin, and the weight ratio of the phenol resin to the aromatic polyester polyol is from 30/70 to 70 /.
30 and an isocyanate group /
The equivalent ratio of hydroxyl groups is in the range of 3.0 to 5.0.

In the continuous foam molding of the flame-retardant foam by reaction between an organic polyisocyanate component and a polyol component, the flame-retardant foam comprises an organic polyisocyanate component and a polyol component as main components, and further includes a necessary foam stabilizer, foaming agent, and catalyst. Foaming is continuously performed by the reaction in the presence of, for example, a mixed solution is sprayed on one face material by means of an airless spray with a double conveyor device, and at the stage of foam hardening, the other face is formed. A foam having a predetermined thickness is continuously formed by applying the material.

Among the polyol components used in the flame-retardant foam, a phenol resin is obtained by adding a specific amount of alkylene oxide to a polynuclear phenol based on heavy oil or pitch as a raw material oil.

As the polynuclear phenol, JP-A-20
What is known as a highly reactive modified phenol resin in JP-A-00-1599 can be used. This highly reactive modified phenolic resin is based on heavy oils or pitches and 1 mol of the base oil calculated from the average molecular weight.
0.3 to 10 mol of a phenol, 0.2 to 9 mol of a formaldehyde compound in terms of formaldehyde, and 0.01 to 3.0 mol of an acid catalyst are mixed, heated and stirred to polycondensate the above components. It can be obtained by doing.

As the heavy oils or pitches used as a raw material in the polycondensation reaction of the highly reactive modified phenolic resin, any of petroleum-based and coal-based raw materials may be used. Distillation residue, hydrogenolysis residue,
Catalytic cracking residue, catalytic reforming residue, pyrolysis residue of naphtha or LPG and vacuum distillation of these residues, extract or heat treatment by solvent extraction, cracking process such as thermal cracking and catalytic cracking in petroleum refining process Examples of the specific extracted oil or residual oil obtained in the above and reduced-pressure distillates of these residual oils, and the like, in coal systems, specific fractionated components obtained by distilling coal tar in coal dry distillation and heavy oil in coal liquefaction And the like.

Examples of the phenol used as a raw material in the polycondensation reaction of the highly reactive modified phenol resin include a hydroxybenzene compound and a hydroxynaphthalene compound. Examples of the hydroxybenzene compound include phenol, cresol, and the like. Xylenol, resorcin, hydroquinone, catechol, phenylphenol, vinylphenol, nonylphenol, p
-Tert-butylphenol, bisphenol A, bisphenol F and the like. Examples of the hydroxynaphthalene compound include monohydroxynaphthalene compounds such as α-naphthol and β-naphthol, 1,2-dihydroxynaphthalene, 1,3-dihydroxy Naphthalene, 1,4-dihydroxynaphthalene and 2,3-dihydroxynaphthalene, 3,6-dihydroxynaphthalene, 1,5-dihydroxynaphthalene,
1,6-dihydroxynaphthalene, 1,7-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, 2,
A dihydroxynaphthalene compound such as 7-dihydroxynaphthalene, and the above mono- or dihydroxynaphthalene compound having an alkyl group and a substituent such as an aromatic group or a halogen atom, for example, 2-methyl-1-naphthol;
4-phenyl-1-naphthol, 1-bromo-2-naphthol, 6-bromo-2-naphthol and the like can be exemplified.

These phenols can be used alone or
Two or more kinds may be used in combination. Further, as a formaldehyde compound used as a raw material in the polycondensation reaction of the highly reactive modified phenol resin, in addition to formaldehyde, a linear polymer such as paraformaldehyde and polyoxymethylene (especially an oligomer) and a cyclic polymer such as trioxane are used. A polymer can be exemplified.

In the polycondensation reaction of the highly reactive modified phenolic resin, an acid catalyst is used to polycondense heavy oils or pitches, formaldehyde compounds and phenols. Sted acids or Lewis acids can be used, but preferably Bronsted acids are used. As Bronsted acids, oxalic acid, toluenesulfonic acid, organic acids such as xylenesulfonic acid and formic acid, inorganic acids such as hydrochloric acid and sulfuric acid,
And solid acids such as acidic cation exchange resins.

Such a specific amount of heavy oils or pitches, a formaldehyde compound, a phenol and an acid catalyst are preliminarily mixed, and then the resulting mixture is heated and stirred to carry out a polycondensation reaction, whereby a highly reactive modification is performed. In a polycondensation reaction in which a phenolic resin is produced or these raw materials and an oxidation catalyst are heated and agitated, heavy oils or pitches, an acid catalyst and at least one of a formaldehyde compound are sequentially added to carry out the polycondensation reaction. Produce highly reactive modified phenolic resin.

Since the polynuclear phenol composed of such a highly reactive modified phenol resin is hard to use at room temperature because it is a solid, by adding 3.0 to 5.0 mol of a specific amount of alkylene oxide. By using a liquefied and liquid phenol resin as a stock solution, a foam having good foaming characteristics is obtained.

Examples of the alkylene oxide to be used in addition to the phenol polynuclear include ethylene oxide, propylene oxide, butylene oxide and the like, and preferably ethylene oxide having high flame retardancy. A phenol polynuclear compound which is solid at ordinary temperature by adding 1 to 6 mol of alkylene oxide, preferably 3.0 to 5.0 mol of alkylene oxide, paying attention to the terminal OH group in the phenol polynuclear compound Is liquefied.

If the addition amount of the alkylene oxide is less than 1 mol, the viscosity is so high that it cannot be said to be a liquid at room temperature. If it exceeds 6 mol, the viscosity is low and it is easy to handle, but the required flame retardancy can be obtained by polymerization. I can't.

As the phenol resin, a resin obtained by adding 3.0 to 5.0 moles of ethylene oxide to a phenol polynuclear compound is preferable. If the amount of ethylene oxide is less than 3.0 mol, the viscosity is high, the compatibility with the isocyanate component is poor, and the cells are roughened. On the other hand, if the amount of ethylene oxide exceeds 5.0 mol, the compatibility is good, but the expected flame retardancy cannot be obtained.

Even if this phenol resin is obtained by adding 3.0 to 5.0 moles of ethylene oxide to a phenol polynuclear compound, if it is used alone, foaming does not occur or cell roughening occurs, and a good foam cannot be obtained. There is a tendency.

Therefore, a foam having high flame retardancy is obtained by combining an aromatic polyester polyol with the phenol resin.

The combination of the phenolic resin and the aromatic polyester polyol has a weight ratio of phenolic resin / aromatic polyester polyol of 30/70 to 70/70.
A range of 30 is preferred. When the weight ratio of phenolic resin / aromatic polyester polyol is less than 30/70, a quasi-noncombustible grade required as a heat insulating material for building cannot be obtained. This is based on the exothermic test (corn calorimeter test), which requires that the maximum heating rate in a 10 minute heating test does not exceed 200 kW / m ² for more than 10 seconds and that the total heating value be 8 MJ / m ² or less. Have been.

When the weight ratio of phenolic resin / aromatic polyester polyol exceeds 70/30, the phenolic resin component increases, and when a foam is formed, cell roughening or poor foaming occurs, and a normal foam is obtained. Can not do.

Aromatic polyester polyols used in combination with this phenol resin include waste PET, DMT
Any residue can be used as long as it can be obtained by transesterification of phthalic anhydride. For example, a Terol series manufactured by Oxide, a Terate series manufactured by Hoechst Celanese, and a Fantor JP series manufactured by Toho Rika are listed.

The equivalence ratio (NCO / OH index) of the isocyanate group to the hydroxyl group of the mixture of the phenol resin and the aromatic polyester polyol is 3.0 to 5.0.
Range. When the equivalent ratio between the isocyanate group and the hydroxyl group is smaller than 3.0, the shrinkage during foam molding is large,
The shape cannot be maintained, and the manufacturing itself cannot be performed. On the other hand, if the equivalent ratio exceeds 5.0, the foam becomes brittle, causing a practical problem.

Incidentally, water can be used as the foaming agent. In this case, the hydroxyl groups of the water are also included in the hydroxyl groups in the above equivalent ratio.

Next, as the organic polyisocyanate component used in the flame-retardant foam, generally used aromatic polyisocyanate, alicyclic polyisocyanate, or aliphatic polyisocyanate can be used. it can.

Specific examples include tolylene 2,4-diisocyanate, tolylene 2,6-diisocyanate, and mixtures thereof, diphenylmethane 4,4'-diisocyanate, 3-methyldiphenylmethane 4,4'-diisocyanate and mixtures thereof, Hexamethylene diisocyanate can be used.

When producing the flame-retardant foam, a foam stabilizer,
A foaming agent, a catalyst and the like can be blended. As the foam stabilizer, conventionally used silicone surfactants are preferable. For example, SH-193 manufactured by Toray Dow, L-5420, L-5421, and SZ-164 manufactured by Nippon Unicar.
2, SZ-1669 and the like.

As a foaming agent, HCFC-141 is used.
b, HFC-245fa, HFC-365mfc, hydrocarbons, for example, cyclopentane, n-pentane, i-pentane or a mixture thereof, or a mixture of water and the like can be used.

Further, examples of the catalyst include tertiary amines such as dimethylmethanolamine, triethylenediamine and tetramethylhexamethylenediamine, and metal catalysts such as potassium acetate and potassium octylate.

As a specific means for producing the flame-retardant foam of the present invention from the above-mentioned raw materials, any apparatus can be used as long as it can uniformly mix the above-mentioned raw materials. The mixture is continuously mixed and sprayed on one face material by means of airless spray or the like, and at the stage of foaming hardening, the other face material is applied and a foam of a predetermined thickness is applied by a double conveyor device. It can be manufactured by continuous molding.

Such a flame-retardant foam is excellent in flame retardancy evaluated by a flame penetration test, a heat generation test and the like, and has a good foam appearance and excellent properties such as density. It will be a very good thermal insulation material compared to conventional thermal insulation materials.

[0039]

EXAMPLES Hereinafter, examples of the flame-retardant foam of the present invention will be specifically described, but the present invention is not limited to these examples. (Examples 1 to 5) and (Comparative Examples 1 to 6) Phenol resin-1 to phenolic resin-6 and polyester polyol A to polyester polyol C were used in Example 1.
About 5 to 5 parts by weight shown in Table 1 and Comparative Examples 1 to 6 in the parts by weight shown in Table 2, and a foam stabilizer,
After blending the foaming agent 1 or the foaming agent 2, the catalyst, water, etc., the NCO / OH index is as shown in Table 1 for Examples 1 to 5, and as shown in Table 2 for Comparative Examples 1 to 6. The organic polyisocyanate component was added to the mixture, and the mixture was stirred and mixed, and foamed in a 50 × 300 × 300 mm aluminum mold heated to 80 ° C. to obtain a foam.

After leaving the obtained foam for 2 days, it was cut into a predetermined size, and the density was measured, and a flame penetration test, a heat generation test, and the like were performed. Here, the thickness is 25 mm
Was measured and tested.

The measurement results and evaluation results are shown in Table 1 for Examples 1 to 5 and Table 2 for Comparative Examples 1 to 6. The following components were used as the components shown in Tables 1 and 2.

Phenol resin-1 FPI5 manufactured by Kashima Oil
1.1 mol of ethylene oxide (hydroxyl value: 125, viscosity of 1,000,000 mPa · s or more (at 20 ° C.) per mol of 524B) Phenol resin-2 2 mol of ethylene oxide (hydroxyl value: 1 mol of FPI5524B manufactured by Kashima Oil) 25
0, viscosity 500,000 mPa · s or more (at 20 ° C.) Phenol resin-3 3 moles of ethylene oxide (hydroxyl value: 21) per mole of FPI5524B manufactured by Kashima Oil
0, viscosity 200,000 mPa · s or more (at 20 ° C.) Phenol resin-4 4 moles of ethylene oxide (hydroxyl value: 18) per mole of FPI5524B manufactured by Kashima Oil
0, viscosity of 45,000 mPa · s or more (at 20 ° C.)) Phenol resin-5 5 moles of ethylene oxide (hydroxyl value: 16 with respect to 1 mole of FPI5524B manufactured by Kashima Oil Company)
0, viscosity 20,000 mPa · s or more (at 20 ° C.)) Phenol resin-6 6 moles of ethylene oxide (hydroxyl value: 14 with respect to 1 mole of FPI5524B manufactured by Kashima Oil Company)
0, viscosity 10,000 mPa · s or more (at 20 ° C.)) Polyester polyol A (aromatic polyester polyol) Oxide Terol 250 (hydroxyl value: 25)
0, waste PET) Polyester polyol B (aromatic polyester polyol) Hoechst Celanese terate 2541 (hydroxyl value: 240, DMT residue) Polyester polyol C (aromatic polyester polyol) Toho Rika JP-708 (hydroxyl value: 250) ,
(Phthalic anhydride) foam stabilizer SH-193 (silicone foam stabilizer) manufactured by Toray Silicone Catalyst potassium octylate / triethylenediamine = 2
/ 1 foaming agent 1 water foaming agent 2 HCFC-141b manufactured by Daikin Organic polyisocyanate M-100 manufactured by Mitsui Chemicals (crude MDI) The measurement and test of each performance were performed by the following methods.

Density (kg / m ³ ): Measured according to JIS A9511 Flame penetration test: Measured according to the United States Mines Bureau standards ◎ In the table, those satisfying the standards are indicated by ○, and those not satisfying are indicated by ×.

Exothermicity test: Cone calorimeter test of quasi-noncombustible material test Measurement by ISO5660 The criterion was a maximum heating rate of 200 kW / m ² .
In the table, the case where the condition was not exceeded for more than one second and the condition that the maximum heat generation rate was 8 MJ / m ² or less was evaluated as good, and the case where the condition was not satisfied was evaluated as x.

[0045]

[Table 1]

[0046]

[Table 2]

(Comparative Examples 7 and 8) As shown in Table 3, Comparative Examples 7 and 8 were obtained by performing the same performance measurements and tests on conventional polyisocyanurate foam and phenol foam as described above.

The polyisocyanurate foam of Comparative Example 7 was prepared by blending a foam stabilizer, a catalyst, a foaming agent, and the like with the above PEG 200, then adding crude MDI so that the NCO / OH index became 4.0, and stirring and mixing. And foamed in a mold heated to 60 ° C. to obtain a foam.

The phenol foam of Comparative Example 8 was prepared by mixing a resole phenolic resin with a foam stabilizer and a foaming agent, and then adding 20 parts by weight of p-toluenesulfonic acid as an acid catalyst to 100 parts by weight of the phenolic resin. The mixture was stirred and mixed, and foamed in a mold heated to 80 ° C. to obtain a foam.

[0050]

[Table 3]

As described above, in each of the examples of the present invention, it can be seen from the results of the flame penetration test and the exothermic test that the flame retardancy is excellent. Is also excellent.

[0052]

According to the flame-retardant foam according to the first aspect of the present invention, the foam appearance is good and the properties such as the density are equal to those of the rigid polyurethane foam. As described above, the flame-retardant material is excellent in a flame penetration test (US Mining Bureau standard) and a heat-generating test (corn calorimeter test of quasi-noncombustible material test: measured by ISO5660). It will be.

According to the flame-retardant foam of the present invention,
By diluting the polynuclear phenol which is solid at normal temperature, the viscosity can be adjusted to an appropriate value, and a foam having excellent flame retardancy can be easily obtained by a conventionally used foam molding line.

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Claims (1)

[Claims] 1. A flame-retardant foam which is continuously foam-molded by a reaction between an organic polyisocyanate component and a polyol component, wherein the polyol component is a phenol polynuclear obtained based on heavy oil or pitches. 3.0 to 5.0 mol of an alkylene oxide is added to the product to form a phenol resin, and the weight ratio of the phenol resin to the aromatic polyester polyol is 30/70.
A flame-retardant foam, characterized in that an isocyanate group / hydroxyl group equivalent ratio in the range of 3.0 to 5.0 is used.