JP2000143764A - Production of polyurethane foam - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing a polyurethane foam usable for a heat insulating material or the like by which a mechanical strength of the polyurethane foam obtained by using water as a blowing agent is improved, and swelling of the foam at the time of foaming is prevented by carrying out an addition polymerization reaction in combination with a urethanation reaction of a specific organic isocyanate with an active hydrogen compound. SOLUTION: When (A) an active hydrogen compound is reacted with (B) an organic isocyanate in the presence of (C) a blowing agent consisting of water, (D) a urethanation catalyst, and (E) optional other additives, a modified organic isocyanate having (B1) an additionally polymerizable functional group obtained by reacting (a) an active hydrogen-containing group of a compound having an additionally polymerizable functional group and the active hydrogen- containing group, with (b) an isocyanate group of an excessive organic polyisocyanate is used at least a part of the component B, and a polyurethane- forming reaction is carried out in combination with the polymerization of the additionally polymerizable functional group.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a polyurethane foam. More specifically, the present invention relates to a polyurethane foam having excellent mechanical strength and a small swelling of the foam upon demolding.

[0002]

2. Description of the Related Art Hitherto, polyurethane foam has been widely used as a heat insulating material for refrigerators, freezers, and constructions, as a cushioning material for furniture and interior materials for automobiles, and as a shock absorbing material. However, since specific fluorocarbons such as CFC-11 became unusable at the end of December 1995 to protect the ozone layer, water that reacts with isocyanate groups and generates carbon dioxide gas has become an effective blowing agent. However, when water is used alone as a foaming agent, there are many problems that the physical properties of the foam are deteriorated and the foam swells at the time of demolding. As a method for improving these, a method using a polyether polyol using a sugar as a starting material (JP-A-10-101762)
And other methods using a polyol component comprising a polyether polyol having a specific hydroxyl value (Japanese Patent Application Laid-Open No. 05-247166, etc.), but these methods are still insufficient in preventing blistering.

[0003]

SUMMARY OF THE INVENTION It is an object of the present invention to improve the mechanical strength of urethane foam, particularly urethane foam using water as a foaming agent, and to prevent the foam from swelling during demolding.

[0004]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to solve such problems, and as a result, have found that an active hydrogen-containing group of a compound having an addition-polymerizable functional group and an active hydrogen-containing group can be used. The above-mentioned problems can be solved by subjecting a modified organic isocyanate having an addition polymerizable functional group obtained by reacting an isocyanate group of an excess organic polyisocyanate with an active hydrogen compound to an addition polymerization reaction together with a urethanation reaction. They found that they could be solved and arrived at the present invention.

That is, the present invention relates to an active hydrogen compound (A)
And the organic isocyanate (B) in the presence of a blowing agent (C) composed of water, a urethanization catalyst (D) and, if necessary, other additives (E) to produce a polyurethane foam. As at least a part of the isocyanate (B), an active hydrogen-containing group of the compound (a) having an addition-polymerizable functional group and an active hydrogen-containing group is reacted with an excess of an isocyanate group of the organic polyisocyanate (b). A method for producing a polyurethane foam, characterized in that a modified organic isocyanate (B1) having an addition-polymerizable functional group is used and a polyurethane-forming reaction is carried out together with polymerization of the addition-polymerizable functional group.

[0006]

DETAILED DESCRIPTION OF THE INVENTION The modified organic isocyanate (B) used in the production of the polyurethane foam according to the present invention.
1) is a method in which an isocyanate group of the organic polyisocyanate (b) and an active hydrogen-containing group of the compound (a) having an addition-polymerizable functional group and an active hydrogen-containing group are mixed in such a ratio that the isocyanate group becomes excessive. It is a modified organic isocyanate having an addition polymerizable functional group obtained by the reaction.

As the organic polyisocyanate (b) required for the synthesis of the modified organic isocyanate (B1) used in the present invention, those conventionally used for polyurethane foams can be used. Examples of such isocyanates include aromatic polyisocyanates, aliphatic polyisocyanates, alicyclic polyisocyanates, araliphatic polyisocyanates, and modified products thereof (for example, carbodiimide-modified, allophanate-modified, urea-modified, buret-modified, isocyanurate, and the like). Denaturation, oxazolidone modification, etc.) and mixtures of two or more of these.

The aromatic polyisocyanate includes aromatic diisocyanate having 6 to 16 carbon atoms (excluding carbon in NCO group; the same applies to the following isocyanates), and 6 to 16 carbon atoms.
20 aromatic triisocyanates and crude products of these isocyanates. As a specific example,
1,3- and 1,4-phenylenediisocyanates,
2,4- and 2,6-tolylene diisocyanate (T
DI), crude TDI, 2,4′- and 4,4′-diphenylmethane diisocyanate (MDI), polymethylene polyphenyl isocyanate (crude MDI), naphthylene-1,5-diisocyanate, triphenylmethane-4,4 ′, 4 ″ -triisocyanate and the like. As the aliphatic polyisocyanate, C 6-
And 10 aliphatic diisocyanates. Specific examples include 1,6-hexamethylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, lysine diisocyanate, and the like.

The alicyclic polyisocyanate includes an alicyclic diisocyanate having 6 to 16 carbon atoms. Specific examples include isophorone diisocyanate,
4,4′-dicyclohexylmethane diisocyanate,
Examples thereof include 1,4-cyclohexane diisocyanate and norbornane diisocyanate. Examples of the araliphatic polyisocyanate include araliphatic diisocyanates having 8 to 12 carbon atoms. As a specific example,
Xylylene diisocyanate, α, α, α ′, α′-tetramethylxylylene diisocyanate, and the like. Specific examples of the modified polyisocyanate include urethane modified MDI, carbodiimide modified MDI, sucrose modified TDI, castor oil modified MDI, and the like. Of these, preferred are TDI, MDI, crude TD
I, crude MDI, sucrose-modified TDI, urethane-modified MD
I, one or more organic polyisocyanates selected from carbodiimide-modified MDI.

The addition polymerizable functional group of the compound (a) having an addition polymerizable functional group and an active hydrogen-containing group used for obtaining the modified organic isocyanate (B1) in the present invention includes a radical polymerizable functional group. And a cationically polymerizable functional group (such as a vinyl ether group or a propenyl ether group) and an anionic polymerizable functional group (such as a vinyl carboxyl group or a cyanoacryloyl group). Among these, a radical polymerizable functional group is preferable.

(A) is not particularly limited, and has, for example, at least one active hydrogen-containing group selected from a hydroxyl group, a mercapto group, a carboxyl group, a primary amino group, a secondary amino group and the like; In addition, an active hydrogen compound having at least one group represented by the following general formula [1] may be mentioned, and two or more compounds may be used in combination. (Wherein, R represents hydrogen, an alkyl group having 1 to 15 carbon atoms or an aryl group having 6 to 21 carbon atoms.) Specific examples of the group represented by the general formula [1] include:
Radical polymerizable unsaturated bond-containing groups such as acryloyl group, methacryloyl group, vinyl group, vinylbenzyl group, vinylphenyl group, and allyl ether group are exemplified. Preferred active hydrogen-containing groups are hydroxyl and mercapto groups, and preferred radically polymerizable unsaturated bond-containing groups are acryloyl, methacryloyl and allyl ether groups. The number of active hydrogen-containing groups in (a) is usually 1 to 8, preferably 1 to 5. The number of radically polymerizable unsaturated bond-containing groups in (a) is usually 1 to 10, preferably 1 to 5.

As a specific example of the above (a), the following (a)
1) to (a4). (A1) polyols [polyhydric alcohols; polyhydric phenols; polyether polyols obtained by adding alkylene oxide (c) thereto; polyether polyols obtained by adding (c) to amines; polyhydric alcohols and polycarboxylic acids (A2) Unsaturated carboxylic acid partial amide of amines (a3) Unsaturated carboxylic acid partial thioester of polythiols (a4) Vinyl having a hydroxyl group Monomers

The polyols used in the production of (a1) include, for example, polyhydric alcohols having 2 to 18 carbon atoms.
(Preferably 2 to 12) dihydric alcohols [ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, 1,4-butanediol, 1,6-hexanediol, 1,3-butylene glycol, diethylene glycol, neopentyl Glycol and the like], 3 to 18 carbon atoms (preferably 3 to 12).
Octahydric or higher alcohols [glycerin, trimethylolpropane, pentaerythritol, diglycerin, α-methylglucoside, sorbitol, xylit, mannitol, glucose, fructose, sucrose, etc.] and a combination of two or more thereof No.

Among the polyols used in the production of (a1), polyhydric phenols include, for example, hydroquinone, bisphenols (bisphenol A, bisphenol F, etc.), formalin low-condensates of phenol compounds (intermediates of novolak resins and resols) Body) and combinations of two or more of these.

Among the polyols used in the production of (a1), amines in the polyether polyol obtained by adding (c) to amines include, for example, ammonia; alkanolamines [mono-, di- or triethanolamine] , Isopropanolamine, aminoethylethanolamine, etc.]; alkylamines having 1 to 20 carbon atoms [methylamine, ethylamine, n-butylamine,
Octylamine, etc.]; alkylene diamines having 2 to 6 carbon atoms [ethylene diamine, hexamethylene diamine, etc.]; polyalkylene polyamines having 2 to 6 carbon atoms in the alkylene group [diethylene triamine, triethylene tetramine, etc.]; 20 aromatic amines [aniline, phenylenediamine, diaminotoluene, xylylenediamine, methylenedianiline, diphenyletherdiamine, etc.]; alicyclic amines having 4 to 15 carbon atoms [isophoronediamine, cyclohexylenediamine, etc.]; carbon Heterocyclic amines of formulas 4 to 15 [piperazine, N-aminoethylpiperazine, 1,4-diaminoethylpiperazine, etc.], and a combination of two or more of these.

The alkylene oxide (c) to be added to polyhydric alcohols, polyphenols or amines includes ethylene oxide (hereinafter abbreviated as EO), propylene oxide (hereinafter abbreviated as PO), 1,2- ,
Examples include 1,4- or 2,3-butylene oxide, styrene oxide, and a combination of two or more of these (when used in combination, random addition or block addition may be used), but only these are limited. It is not something to be done. Among these, preferred are those containing PO and / or EO as a main component and containing not more than 20% by mass of another alkylene oxide. The addition reaction is
It can be performed by a conventionally known ordinary method.

Among the polyols used in the production of (a1), the polyhydric alcohols used for the polyester polyol include the same ones as described above. Examples of the polycarboxylic acids include aliphatic polycarboxylic acids [succinic acid, adipine Acids, sebacic acid, maleic acid, fumaric acid, etc.], aromatic polycarboxylic acids [phthalic acid or its isomers, trimellitic acid, etc.], ester-forming derivatives of these polycarboxylic acids [acid anhydrides, alkyl groups And lower alkyl esters having 1 to 4 carbon atoms] and a combination of two or more of these.

(A1) is obtained by partially esterifying the polyols exemplified above with unsaturated carboxylic acids. As the unsaturated carboxylic acids, (meth)
Acrylic acid, crotonic acid, maleic acid, fumaric acid, itaconic acid, citraconic acid, mesaconic acid, anionic acid,
Cinnamic acid, vinyl benzoic acid, etc., and a combination of two or more of these [herein, (meth) acrylic acid means acrylic acid or methacrylic acid, and the same description will be used hereinafter. Ester-forming derivatives of these unsaturated carboxylic acids, such as halides (such as (meth) acrylic acid chloride), acid anhydrides [such as maleic anhydride, itaconic anhydride, and citraconic anhydride]; In combination of two or more. Specific compounds of (a1) include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate,
-Hydroxybutyl (meth) acrylate, 3-phenoxy-2-hydroxypropyl (meth) acrylate,
Examples include glycerin mono (meth) acrylate, glycerin di (meth) acrylate, diethylene glycol mono (meth) acrylate, and the like, and combinations of two or more of these.

(A2) can be obtained by reacting the above-mentioned amines with the above-mentioned unsaturated carboxylic acids, unsaturated carboxylic acid chlorides, unsaturated carboxylic anhydrides and the like. Specific compounds include (meth) acrylamidoethylamine, (meth) acrylamidohexylamine, and the like, and combinations of two or more of these.

Examples of the polythiols used in the production of (a3) include ethanedithiol, 1,2-propanedithiol, 1,3-propanedithiol, 1,4-propanedithiol, 1,4-benzenedithiol,
2-benzenedithiol, bis (4-mercaptophenyl) sulfide, 4-t-butyl-1,2-benzenedithiol, ethylene glycol dithioglycolate, trimethylolpropane tris (thioglycolate) thiocyanuric acid, di (2-mercapto Ethyl) sulfide,
Di (2-mercaptoethyl) ether and their 2
Combinations of more than one species may be mentioned. (A3) can be obtained by reacting these polythiols with the above-mentioned unsaturated carboxylic acids, unsaturated carboxylic acid chlorides, unsaturated carboxylic anhydrides, and the like. Specific compounds include acryloylthioethylmercaptan, acryloylthiobutylmercaptan, and the like, and combinations of two or more of these.

Examples of (a4) include p-hydroxylstyrene, (meth) allyl alcohol, cinnamyl alcohol, crotonyl alcohol, allyl ethers of the above-mentioned polyhydric alcohols (such as pentaerythritol triallyl ether), and those compounds. Examples include the above-mentioned alkylene oxide (c) adducts, and combinations of two or more thereof.

Among these, preferred are unsaturated carboxylic acid partial esters (a1) of polyols and vinyl monomers having a hydroxyl group (i.e., low viscosity and low viscosity of modified organic isocyanate). a4) (especially allyl etherified products of polyhydric alcohols), particularly preferably an unsaturated carboxylic acid partial ester of a polyhydric alcohol or an alkylene oxide adduct thereof, and most preferably diethylene glycol mono (meth) acrylate. . The molecular weight per active hydrogen-containing group (a) is preferably from 40 to 500 in consideration of the viscosity of the modified organic isocyanate.
And particularly preferably 45 to 400.

The reaction between the compound (a) having an addition-polymerizable functional group and an active hydrogen-containing group and the organic polyisocyanate (b) is carried out by the reaction of the active hydrogen-containing group (b) with an isocyanate equivalent of (a). The usual urethanization reaction is carried out at a ratio such that the amount becomes excessive with respect to the equivalent. In the above reaction, (equivalent of active hydrogen-containing group) :( equivalent of isocyanate group) is preferably 1: (1.2 to 10), more preferably 1:
(1.5 to 4). The isocyanate equivalent of (B1) used in the production method of the present invention obtained by this reaction is preferably 95 to 800, more preferably 100 to 700,
The addition polymerizable functional group equivalent is preferably 150 to 5000,
More preferably, it is 180-3000. When the isocyanate equivalent and the addition-polymerizable functional group equivalent are within the above ranges, the foam swelling at the time of demolding when producing a polyurethane foam becomes smaller. Further, the number of isocyanate groups in (B1) is preferably 1 to 6, more preferably 2 to 3, and the number of addition-polymerizable functional groups in (B1) is preferably 1 to 6, more preferably 2-4
Individual.

In the production method of the present invention, as the organic isocyanate (B), in addition to (B1), an organic polyisocyanate (B2) used in a usual production method of a polyurethane foam is used in a range not to impair the effects of the present invention. You can also. Examples of (B2) include the same as the above-mentioned organic polyisocyanate (b). (B2)
The preferred range of the isocyanate equivalent and the addition-polymerizable functional group equivalent of (B) when (B1) is used together is the same as the range when (B1) alone is used.

Active hydrogen compound (A) used in the present invention
Is usually 2 or more, preferably (average) 2.5 or more,
More preferably, it is at least one compound having (average) 3 to 8 active hydrogen-containing groups and not having an addition-polymerizable functional group. As the active hydrogen-containing group of (A),
One or more active hydrogen-containing groups selected from a hydroxyl group, a mercapto group, and an amino group are included. Preferable examples of (A) include a compound having an active hydrogen-containing group selected from a hydroxyl group, a mercapto group and an amino group, preferably a compound having 2 to 8 (particularly 3 to 8) hydroxyl groups. Examples include at least one polyol selected from the group consisting of polyether polyols and polyester polyols.

As the polyether polyol, known ones usually used for polyurethane foams, for example,
Polyether polyols obtained by adding the above-mentioned alkylene oxide (c) to the above-mentioned polyhydric alcohols, polyhydric phenols, polycarboxylic acids, amines and the like are included. Preferred as (c) is one containing PO and / or EO as a main component and containing not more than 20% by mass of another alkylene oxide, particularly preferably PO and / or EO. Examples of the polyester polyol include known ones usually used for polyurethane foams, for example, polyester polyols derived from the above-mentioned polyhydric alcohols or polyphenols and the above-mentioned polycarboxylic acids. Particularly preferred as (A) are polyether polyols obtained by adding alkylene oxide (c) to polyhydric alcohols. The number average molecular weight of (A) is preferably from 50 to 10,000, and particularly preferably from 60 to 8000.

In the present invention, if necessary, the vinyl polymer (F) can be further dispersed in (A) before use. (F) may be dispersed in (A) after the polymerization, but preferably vinyl monomer (f) in (A)
Are polymerized and stably dispersed for use. (F)
For example, acrylonitrile, styrene, vinylidene chloride,
Alkyl (meth) acrylate and the like can be mentioned. Preferably, they are acrylonitrile and styrene. The amount of (F) is usually 5 to 50 parts by mass per 100 parts by mass of (A),
Preferably it is 15 to 45 parts by mass.

In the production method of the present invention, the above-mentioned compound (a) having an addition-polymerizable functional group and an active hydrogen-containing group is used in combination with the active hydrogen compound (A) as a reaction component with the organic isocyanate (B), if necessary. It is possible to When used together, the amount of (a) based on the total mass of (A) and (a) is preferably from 1 to 99% by mass, more preferably from 2 to 95% by mass.

In the method of the present invention, an addition-polymerizable functional group-containing compound (G) having no active hydrogen-containing group can be used together if necessary. Two or more kinds may be used as (G). Examples of the addition-polymerizable functional group (G) include radically polymerizable acryloyl, methacryloyl, vinyl, vinylbenzyl, vinylphenyl,
One or more radically polymerizable unsaturated bond-containing groups selected from an allyl ether group and the like are included. Preferred radically polymerizable unsaturated bond-containing groups are an acryloyl group, a methacryloyl group and an allyl ether group. The number of radically polymerizable unsaturated bond-containing groups in (G) is usually 1 to 10, preferably 1 to 8. (G) is (A)
And usually not more than 50% by mass based on the total mass of
Preferably it is 1 to 30% by mass or less.

As (G), aromatic hydrocarbon monomers (styrene, α-methylstyrene, etc.), unsaturated nitriles ((meth) acrylonitrile, etc.) and the like can also be used. Preferred specific examples include the following (G1) to (G3). (G1) polyols [polyhydric alcohols; polyhydric phenols; polyether polyols obtained by adding alkylene oxide (c) thereto; polyether polyols obtained by adding (c) to amines; polyhydric alcohols and polycarboxylic acids (G2) unsaturated carboxylic acid amidates of amines (G3) unsaturated carboxylic acid thioesters of polythiols

(G1) is used for the production of (a1).
It is obtained by reacting polyols with unsaturated carboxylic acids, unsaturated carboxylic acid chlorides, unsaturated carboxylic anhydrides, and the like. (G2) is obtained by reacting amines and unsaturated carboxylic acids, unsaturated carboxylic acid chlorides, unsaturated carboxylic anhydrides, etc. used in the production of (a2). (G3) is obtained by reacting a polythiol with an unsaturated carboxylic acid, an unsaturated carboxylic acid halide, an unsaturated carboxylic anhydride and the like used in the production of the above (a3).

As a method for molding a usual polyurethane foam, (b) is used as an isocyanate component, whereas in the method of the present invention, a modified organic isocyanate (B1) having both an isocyanate group and an addition-polymerizable functional group is used.
By using the organic isocyanate (B) consisting of, a polyurethane foam having more excellent mechanical strength than the conventional method can be molded.

In the process according to the invention, the NCO index is preferably between 40 and 500, particularly preferably between 60 and 250.
When the NCO index is less than 40, the amount of heat generated during foaming is small, so that the foaming ratio may be reduced or the mechanical strength of the foam may be reduced. On the other hand, the NCO index is 50
If it exceeds 0, the foam may become brittle. In the present invention, performing the polyurethane-forming reaction together with the polymerization of the addition-polymerizable functional group means performing the urethanization reaction and the addition polymerization reaction in the same reaction system. It is preferable that the polymerization of the addition-polymerizable functional group and the polyurethane-forming reaction be performed at least partially in parallel. In order to increase the crosslink density and improve the mechanical properties, it is necessary to start the other reaction before curing and forming the resin in one reaction, and to carry out the two reactions in parallel. More preferred.

In the present invention, although the foam swells at the time of demolding is small, a part of the urethane bond present in the urethane foam finally obtained is modified with a modified organic isocyanate (B).
Since 1) is generated at the time of synthesis, the amount of heat generated at the time of urethane foam foaming does not become extremely high, and the fact that the foam internal temperature is kept at 160 ° C. or lower is one of the factors that reduce swelling. Conceivable.

As the foaming agent (C), water is essential.
When only water is used alone in (C), the amount of water used is (A) [When both (A) and (a) are used together, the total amount of (A) and (a) The same applies to))
The amount is usually 0.1 to 30 parts by mass, preferably 1 to 20 parts by mass, per 100 parts by mass. In addition, a hydrogen atom-containing halogenated hydrocarbon, a low boiling point hydrocarbon, liquefied carbon dioxide, or the like is used as necessary.

Specific examples of the hydrogen atom-containing halogenated hydrocarbon include those of the HCFC (hydrochlorofluorocarbon) type (for example, HCFC-123, HCF
C-141b, HCFC-22 and HCFC-142
b) HFC (hydrofluorocarbon) type (for example, HFC-134a, HFC-152a, HF
C-356mff, HFC-236ea, HFC-24
5ca, HFC-245fa and HFC-365mc
f) and the like. Preferred of these are:
HCFC-141b, HFC-134a, HFC-35
6mff, HFC-236ea, HFC-245ca,
HFC-245fa, HFC-365mcf and a combination of two or more thereof. The low boiling point hydrocarbon is a hydrocarbon having a boiling point of usually -5 to 70 ° C, and specific examples thereof include butane, pentane, cyclopentane and a mixture thereof.

When a hydrogen atom-containing halogenated hydrocarbon compound is used in combination with water, the amount of the hydrogen atom-containing halogenated hydrocarbon compound used is usually 4 parts per 100 parts by mass of (A).
The amount is not more than 5 parts by mass, preferably 5 to 40 parts by mass.
The amount does not exceed parts by mass, preferably 0.5 to 8 parts by mass. When a low-boiling hydrocarbon and water are used in combination, the amount of the low-boiling hydrocarbon used is usually not more than 40 parts by mass, preferably 2 to 35 parts by mass, per 100 parts by mass of (A).
The amount of water to be used is generally not more than 10 parts by mass, preferably 0.5 to 8 parts by mass, per 100 parts by mass of (A).
When liquefied carbon dioxide gas and water are used in combination, the amount of liquefied carbon dioxide gas used is usually not more than 25 parts by mass, preferably 0.1 to 20 parts by mass, per 100 parts by mass of (A). The amount is usually not more than 10 parts by mass, preferably 0.5 to 8 parts by mass, per 100 parts by mass of (A).

The urethanization catalyst (D) used in the production method of the present invention is a catalyst usually used for polyurethane reaction, for example, an amine catalyst (triethylenediamine, N-
Ethyl morpholine, diethyl ethanolamine, N,
N, N ′, N′-tetramethylhexamethylenediamine, 1-isobutyl-2-methylimidazole, 1,8
-Diazabicyclo- [5,4,0] -undecene-7) and / or metal catalysts (such as stannous octylate, dibutylstannic dilaurate, lead octylate, etc.) can be used. The amount of the catalyst used is preferably 0.001 to 6 parts by mass per 100 parts by mass of the total of (A) and (a) used if necessary.

In the production method of the present invention, if necessary, the reaction may be carried out in the presence of another additive (E) as described below. In the method of the present invention, when the addition-polymerizable functional group of the modified organic isocyanate (B1) is a radical-polymerizable unsaturated bond-containing group, the reaction can be carried out in the presence or absence of a radical polymerization initiator. Examples of the radical polymerization initiator that can be used include known radical polymerization initiators such as azo compounds [2,2′-azobisisobutyronitrile, 2,2′-azobis-
(2,4-dimethylvaleronitrile), 1,1′-azobis- (1-acetoxy-1-phenylethane), etc.), peroxides (dibenzoyl peroxide, benzoyl peroxide, dicumyl peroxide, etc.),
Oil-soluble radical polymerization initiators such as a combination of peroxide and dimethylaniline (redox); azobiscyanovaleric acid, azobisamidinopropane salt, potassium persulfate, a combination of sodium persulfate and sodium bisulfite (redox) And the like, and preferably an oil-soluble radical polymerization initiator. The amount of the radical polymerization initiator is preferably 0.0001 to 10 parts by mass, more preferably 0.0005 to 1 part per 100 parts by mass of the total of (B1) and (G) and / or (a) used as required. Parts by weight.

If necessary, the reaction can be carried out in the presence of a chain transfer agent, for example, alkyl mercaptans (dodecyl mercaptan, mercaptoethanol, etc.) and enol ethers described in JP-A-55-31880. The amount of the chain transfer agent is preferably 0.0001 to 10 parts by mass, more preferably 0.0005 to 1 part per 100 parts by mass of the total of (B1) and (G) and / or (a) used as required. Parts by weight.

In the present invention, a flame-retardant polyurethane foam can be obtained by further performing a polyurethane forming reaction and an addition polymerization reaction in the presence of an inorganic filler. Specific examples of the inorganic filler include aluminum hydroxide, silica, kaolin, talc, mica, calcium carbonate, barium sulfate, zinc oxide, titanium oxide, crushed stone, alumina, fly ash, bentonite, and ceramic powders. , Asbestos, rock wool, glass fiber, ceramic fiber, carbon fiber, and other powders or fibers. Of these, aluminum hydroxide or silica is preferred. When the amount of the inorganic filler is used, the amount is preferably 10 to 60 parts by mass per 100 parts by mass of the total of (A) and (B) and the optional components (G) and / or (a). Especially preferably, it is 30 to 50 parts by mass. When it is 10 parts by mass or more, the flame retardancy is good, and when it is 60 parts by mass or less, the mechanical strength of the foam is improved.

Further, if necessary, a foam stabilizer, a polymerization inhibitor,
Colorant (dye, pigment), plasticizer, organic filler, flame retardant,
The reaction can be carried out in the presence of known additives such as an antioxidant and an antioxidant.

An example of a method for producing a polyurethane foam according to the method of the present invention is as follows. First,
(A), (C), (D) and, if necessary, (a),
(F), (G), a foam stabilizer, a radical polymerization initiator, and other additives are mixed in predetermined amounts. This mixture is then rapidly mixed with the organic isocyanate (B) using a polyurethane foaming machine or a stirrer. The obtained liquid mixture (foaming stock solution) is poured into a mold, and an addition polymerization reaction is performed together with a urethanization reaction. After curing for a predetermined time, the mold is removed to obtain a polyurethane foam. Further, a polyurethane foam can be obtained by spray foaming or continuous foaming.

The polyurethane foam obtained by the method of the present invention has high mechanical strength and small swelling during demolding, so that it can be used as a heat insulating material for refrigerators, freezers, buildings, etc., furniture, cushioning materials for automobile interior materials, Can be widely used as shock absorber. Further, the polyurethane foam obtained by the method of the present invention has a high mechanical strength, and is therefore advantageous for lowering the density.

Hereinafter, the present invention will be further described with reference to examples, but the present invention is not limited to these examples. In the following, “parts” and “%” are based on mass, respectively.

[0046]

EXAMPLES Production Example 1 80 parts of Millionate MR-100 (b-1, manufactured by Nippon Polyurethane Industry Co., Ltd., polymethylene polyphenylene polyisocyanate) and glycerin dimethacrylate 20
Of the modified organic isocyanate (B1-
1) was obtained. The isocyanate equivalent was 200 and the addition polymerizable functional group equivalent was 570.

Production Example 2 80 parts of TDI (b-2) and 20 parts of triethylene glycol monoacrylate were charged into a kolben, and heated and stirred at 70 ° C. for 5 hours to carry out a urethane-forming reaction, whereby a modified organic isocyanate (B1-2) was obtained. Obtained. Isocyanate equivalent 12
0, the addition polymerizable functional group equivalent was 1020.

Example 1 PO8 mole adduct of pentaerythritol (A-1) 1
00 parts, 1.5 parts of "Silicone SH-193" (manufactured by Toray Silicone Co., Ltd., silicone-based foam stabilizer), 7 parts of water,
0.2 parts of butyl peroxide and “Ucat-1”
000 "(manufactured by San-Apro Co., Ltd., amine catalyst) was mixed and temperature-controlled to 25 ° C, and 289 parts of (B1-1) temperature-controlled to 25 ° C was added thereto, and homodisper (special machine) was added. After stirring at 4000 rpm for 10 seconds, the temperature was adjusted to 60 ° C. and 1000 mm (length) × 10.
In an aluminum mold of 0 mm (width) x 100 mm (height), an addition polymerization reaction is performed together with a urethanization reaction,
After 10 minutes, the mold was released to obtain a rigid polyurethane foam.

Example 2 100 parts of adduct of sucrose with 15 mol of PO (A-2), 1.5 parts of "Silicone SH-193" (manufactured by Toray Silicone Co., silicone-based foam stabilizer), 7 parts of water, -0.2 parts of butyl peroxide and 2.0 parts of "Ucat-1000" (manufactured by San Apro Co., Ltd., amine catalyst) were blended at 25C
The temperature was adjusted to 25 ° C. (B1-
1) The same operation as in Example 1 was performed by adding 287 parts,
A rigid polyurethane foam was obtained.

Comparative Example 1 PO8 mole adduct of pentaerythritol (A-1) 1
00 parts, 1.0 part of "Silicone SH-193" (manufactured by Toray Silicone Co., silicone-based foam stabilizer), 5 parts of water, and 1.4 parts of "Ucat-1000" (manufactured by San Apro Co., amine catalyst) The temperature was adjusted to 25 ° C, 165 parts of (b-1) adjusted to 25 ° C were added thereto, and the mixture was stirred for 10 seconds at 4000 rpm with a homodisper (a stirrer manufactured by Tokushu Kika Co., Ltd.). A urethanization reaction was performed in an adjusted 1000 mm (length) × 100 mm (width) × 100 mm (height) aluminum mold, and after 10 minutes, the mold was released to obtain a rigid polyurethane foam.

Comparative Example 2 100 parts of adduct (A-2) of sucrose with 15 mol of PO, 1.0 part of "Silicone SH-193" (manufactured by Toray Silicone Co., Ltd., silicone-based foam stabilizer), 5 parts of water, and " Ucat
-1000 "(manufactured by San-Apro Co., Ltd., amine catalyst) in an amount of 1.4 parts, the temperature was adjusted to 25 ° C, and 164 parts of (b-1) adjusted to 25 ° C was added thereto. The same operation was performed to obtain a rigid polyurethane foam.

Example 3 100 parts of polyol (A-3) obtained by adding 73 mol of PO to glycerin and then 16 mol of EO, 2 parts of triethanolamine, "Silicone L-5309" (a silicone-based foam stabilizer manufactured by Nippon Unicar Co., Ltd.) 1.5 parts, water 3.5 parts,
0.2 parts of di-t-butyl peroxide and "TEDA
L33 "(manufactured by Tosoh Co., Ltd., amine catalyst) was mixed with 0.5 part and the temperature was adjusted to 25 ° C, and 58.7 parts of (B1-2) temperature-controlled to 25 ° C was added thereto, and homodisper ( Stirrer manufactured by Tokushu Kika Co., Ltd.) After stirring at 4000 rpm for 10 seconds, the temperature was adjusted to 60 ° C., 300 mm (length) × 300.
The addition polymerization reaction is carried out together with the urethane reaction in an aluminum mold of mm (width) x 100 mm (height).
After minutes, the mold was released to obtain a flexible polyurethane foam.

Comparative Example 3 100 parts of polyol (A-3) obtained by adding 73 mol of PO to glycerin and then adding 16 mol of EO, 2 parts of triethanolamine, "Silicone L-5309" (a silicone foam stabilizer manufactured by Nippon Unicar Co., Ltd.) 1.3 parts, water 3.0 parts,
And 0.4 part of “DABCO 33LV” (manufactured by Tosoh Corporation, amine catalyst) were blended and the temperature was adjusted to 25 ° C., and 37.7 parts of (b-2) temperature-controlled to 25 ° C. were added thereto, Homodisper (Stirrer manufactured by Tokushu Kika) 4000r
After stirring at pm for 10 seconds, the temperature was adjusted to 60 ° C.
(Length) x 300mm (width) x 100mm (height)
The urethane-forming reaction was performed in an aluminum mold, and after 6 minutes, the mold was released to obtain a flexible polyurethane foam.

Test Example Test of rigid urethane foam: A sample of a cubic body having a compressive strength of 50 mm on a side from the core of the foam was cut out.
It was measured according to JIS A9514. Compression was performed in the height direction. The blister was released from the mold 5 minutes after foaming, and measured in the thickness direction. In each of Examples 1 and 2 and Comparative Examples 1 and 2,
Table 1 shows the compressive strength and swelling of the obtained foam. Testing of flexible urethane foam: Hardness, elongation and tear strength were measured according to JIS K6401 and JIS K6, respectively.
It was measured in accordance with No. 301. The blister was released from the mold 6 minutes after foaming, and measured in the thickness direction. Table 2 shows the hardness, elongation, tear strength and swelling of the foams obtained in Example 3 and Comparative Example 3.

[0055]

[Table 1]

[0056]

[Table 2]

[0057]

According to the process for producing a polyurethane foam of the present invention, a polyurethane foam having a high mechanical strength and a small swelling of the foam upon demolding can be obtained. Because of the above effects, the rigid polyurethane foam obtained by the method of the present invention is extremely useful as a refrigerator, a freezer, and a heat insulating material for building materials.The flexible polyurethane foam obtained by the method of the present invention is used for furniture, It is extremely useful as a cushioning material for automobile interior materials and a shock absorbing material.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C08G 101: 00) F-term (Reference) 4F074 AA84 AD13 AD18 BA32 BA34 BA42 BB23 CA23 DA32 DA33 DA35 DA47 4J034 BA07 BA08 DF01 DF16 DF17 DG02 DG14 DQ04 DQ05 DQ15 DQ16 DQ18 DQ23 EA07 EA12 FA01 FA02 FB01 FB06 FC01 FD01 FD03 FE06 GA51 GA52 GA55 GA65 GA67 HA01 HA02 HA06 HA07 HA08 HB06 HB07 HB08 HB09 HC03 HC12 HC63 HC17 HC53 HC17 HC71 HC73 JA22 JA42 KA01 KB02 KC17 KC18 KD02 KD12 KE02 NA02 NA03 NA06 QA02 QA07 QB14 QC01

Claims (5)

[Claims] 1. A reaction between an active hydrogen compound (A) and an organic isocyanate (B) in the presence of a blowing agent (C) composed of water, a urethanization catalyst (D) and, if necessary, other additives (E). In the method for producing a polyurethane foam, an active hydrogen-containing group of a compound (a) having an addition-polymerizable functional group and an active hydrogen-containing group as at least a part of the organic isocyanate (B), and an excess of an organic polyisocyanate (B). b) a modified organic isocyanate having an addition polymerizable functional group obtained by reacting
A method for producing a polyurethane foam, comprising conducting a polyurethane-forming reaction together with the polymerization of an addition-polymerizable functional group using 1). 2. An isocyanate equivalent of (B1) of from 95 to
2. The method for producing a polyurethane foam according to claim 1, wherein the equivalent weight of the addition-polymerizable functional group is from 800 to 150. 3. The method for producing a polyurethane foam according to claim 1, wherein (a) is an active hydrogen compound having an active hydrogen-containing group and a terminal olefin group represented by the following general formula [1]. (In the formula, R represents hydrogen, an alkyl group having 1 to 15 carbon atoms, or an aryl group having 6 to 21 carbon atoms.) 4. (a) has at least one or more addition-polymerizable functional groups selected from an acryloyl group, a methacryloyl group and an allyl ether group, and (a) the active hydrogen-containing group is a hydroxyl group and / or The method for producing a polyurethane foam according to any one of claims 1 to 3, which is a mercapto group. 5. The method for producing a polyurethane foam according to claim 1, wherein (A) is a polyether polyol and / or a polyester polyol.