JPH0525242A - Method for manufacturing soft urethane foam - Google Patents

Abstract

PURPOSE:To produce a flexible urethane foam. CONSTITUTION:A process for producing a flexible urethane foam wherein at least one of the polyol components of the polyol composition comprises a polyether polyol (polyol A) which is formed by adding ethylene oxide to the interior of the molecule and adding propylene oxide to its terminal, has a primary hydroxyl concentration of 15wt.% or below, a hydroxyl value of 30-100 mgK0H/g and an ethylene oxide content of 5-30mol%, the polyol being used in an amount of 30wt.% or above based on the polyol composition, and the catalyst used is a mixture of a trimerization catalyst with a urethane formation catalyst. A flexible urethane foam excellent in properties can be obtained by using only water without using any halohydrocarbon.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a method for producing a flexible urethane foam. More specifically, it relates to a method for producing a flexible flexible urethane foam that does not require a halogenated hydrocarbon as a blowing agent.

[0002]

2. Description of the Related Art Conventionally, water and halogenated hydrocarbons have been mainly used as a foaming agent in the production of urethane foam. In this case, since water alone reacts to increase the number of hard segments in the polymer and cannot be softened, halogenated hydrocarbons that do not participate in the reaction are used together to reduce the density and hardness. Came. However, halogenated hydrocarbons, especially chlorofluorocarbons,
As a substance that destroys the ozone layer, it has been widely taken up by society, and its release has become a major environmental conservation problem.
In order to produce a flexible urethane foam without using a halogenated hydrocarbon, according to the conventionally known concept, A. NC
Lower the O index, B. A possible method is to reduce the density by increasing the amount of water. But for A,
The effect is small because the density is increased, and the cure property of the foam surface is deteriorated. In the case of B, the hard segment is increased and the effect of lowering hardness is small, and the reactivity is increased, so that the moldability is deteriorated. There were some difficulties.

[0003]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a method for producing a flexible flexible urethane foam which does not use a halogenated hydrocarbon and overcomes the drawbacks of these conventional methods.

[0004]

Means for Solving the Problems The inventors of the present invention have made extensive studies in order to solve the above-mentioned problems, and as a result, in the production of flexible urethane foam, the reaction was carried out by a polyol composition containing a specific polyol A, trimerization. It was found that the above object can be achieved by carrying out the reaction in the presence of a catalyst and a urethanization catalyst, and the present invention has been completed based on this finding.

That is, according to the present invention, when a flexible urethane foam is produced by reacting a polyol composition with an organic polyisocyanate in the presence of a foaming agent, a foam stabilizer and a catalyst, at least one of the polyol compositions is This type has an average number of functional groups of 2.5 to 3.0 and has ethylene oxide added inside the molecule and propylene oxide added at the end of the molecule.
30 ~ 100mgKOH / g, ethylene oxide content 5 ~ 30
Mol% of polyether polyol (hereinafter referred to as polyol A), wherein the proportion of the polyol A is 30% by weight or more of the polyol composition, and a mixture of a trimerization catalyst and a urethanization catalyst is used. Is a method for producing a flexible urethane foam.

The polyol composition used in the present invention is various polyols as described below. Monomer polyols such as ethylene glycol, propylene glycol, diethylene glycol, triethylene glycol, dipropylene glycol, trimethylene glycol, 1,3- and 1,4-butanediol, alkanolamines such as triethanolamine and diethanolamine, or As an initiator, water, ethylene glycol, propylene glycol, diethylene glycol, triethylene glycol,
Dipropylene glycol, trimethylene glycol,
1,3- and 1,4-butanediol, 1,5-pentanediol, 1,2-hexylene glycol, 1,10-
Decanediol, 1,2-cyclohexanediol, 2
-Butene-1,4-diol, 3-cyclohexane-
1,1-dimethanol, 4-methyl-3-cyclohexane-1,1-dimethanol, 3-methylene-1,5-pentanediol, (2-hydroxyethoxy) -1-propanol, (2-hydroxyethoxy) -1-butanol, 5- (2-hydroxypropoxy) -1-pentanol, 1- (2-hydroxypropoxy) -2-octanol, 3-allyloxy-1,5-pentanediol, 2-allyloxymethyl-2. -Methyl-1,3-pentanediol, [(4,4-pentyloxy) -methyl]
-1,3-propanediol, 3- (o-propenylphenoxy) -1,2-propanediol, 2,2'-diisopropylidenebis (p-phenyleneoxy) diethanol, glycerin, 1,2,6-hexane Triol, 1,1,1-trimethylolethane, 1,1,1-
Trimethylolpropane, 3- (2-hydroxyethoxy) -1,2-propanediol, 3- (2-hydroxypropyl) -1,2-propanediol, 2,4-dimethyl-2- (2-hydroxyethoxy) -Methylpentanediol-1,5,1,1,1-tris [(2-hydroxy) methyl] ethane, 1,1,1-tris [(2
-Hydroxypropyl) -methyl] propane, pentaerythritol, sorbit, sucrose, lactose, α-methyl glycoside, α-hydroxyalkyl glycoside, novolac resin, phenol-aniline-formaldehyde three-dimensional condensation product, aniline-formaldehyde condensation product Compounds, caprolactones, ethylenediamine, diethylenetriamine, aliphatic polyamines such as triethylenetetramine, methyleneorthochloroaniline, 4,4'-diphenylmethanediamine, aniline, 2,4-tolylenediamine, 2,6-tolylenediamine, etc. Alkanolamines such as aromatic polyamines, triethanolamine, diethanolamine, etc., such as ethylene oxide, propylene oxide, butylene oxide, tetrahydrofuran,
Polyether polyols obtained by adding one or more of styrene oxide and the like, or polytetramethylene ether glycol, ethylene glycol,
Propylene glycol, diethylene glycol, triethylene glycol, dipropylene glycol, trimethylene glycol, 1,3- and 1,4-butanediol, tetramethylene glycol, neopentyl glycol, hexamethylene glycol, decamethylene glycol, glycerin, trimethylolpropane , Pentaerythritol, sorbit, etc., and one or more compounds having at least two hydroxyl groups, and malonic acid,
Maleic acid, succinic acid, adipic acid, tartaric acid, pimelic acid, sebacic acid, oxalic acid, phthalic acid, terephthalic acid,
Ring-opening polymers of polyester polyols from one or more compounds having at least two carboxyl groups such as trimellitic acid and hemimellitic acid, or cyclic esters such as polycaprolactone, and JP-B-39-2.
No. 4734, Japanese Patent Publication No. 41-3473, Japanese Patent Publication No. 43-2
No. 2108, Japanese Patent Publication No. 44-8230, Japanese Patent Publication No. 47-4
7597, Japanese Patent Publication No. 47-47999, Japanese Patent Laid-Open No. 48-
34991, JP-A-51-50398, JP-A-51
-70286, JP-A-52-11249, JP-A-5
3-4092, JP-A-53-13700, JP-A-54
-64264, JP-A-53-78297, JP-A-5
There is a so-called polymer polyol composition obtained by graft-polymerizing an ethylenically unsaturated compound in the polyester polyol and / or polyether polyol described in JP-A-4-133599 and JP-A-55-5988.
Suitable ethylenically unsaturated compounds for preparing such compositions include acrylonitrile, styrene and the like. Furthermore, 1,2-polybutadiene polyol and 1,4-polybutadiene polyol are used.

The above-mentioned various polyols, including the above-mentioned polyol A, are mixed to form a polyol composition. Also, the preferable range of the hydroxyl value is 2
0 to 150 mg KOH / g and a hydroxyl number of 20
When it is less than mgKOH / g, it is difficult to reduce the density of the soft urethane foam obtained. If it exceeds 150mgKOH / g, the impact resilience of the flexible urethane foam is low,
Easy to shrink. The polyol A in the polyol composition described above is as described above. If the average number of functional groups of the polyol A is less than 2.5, the compression set of the resulting urethane foam will be poor, and if it exceeds 3.0, the urethane foam will be hard. By using a so-called propylene oxide cap type in which ethylene oxide is added inside the molecule and propylene oxide is added to the end of the molecule, the effect of softening the urethane foam is enhanced. In this case, the content of ethylene oxide is 5 to 30 mol%. When it is less than 5 mol%, the effect of softening the foam is small, and when it exceeds 30 mol%, cracks and voids occur in the urethane foam. Moldability deteriorates.

The concentration of primary hydroxyl groups of polyol A is 15% by weight or less. When the amount is more than 15% by weight, the softening effect of the urethane foam is small. The hydroxyl number is 30 to 100 mgKOH / g. When the hydroxyl value is less than 30 mgKOH / g, it is difficult to lower the density of the urethane foam, and when it exceeds 100 mgKOH / g, the impact resilience of the urethane foam is low and the urethane foam is likely to shrink. The content of polyol A in the polyol composition is 30% by weight or more, preferably 40 to 80% by weight, more preferably 50 to 70% by weight. When it is less than 30% by weight, the effect of softening the urethane foam is small.

The organic polyisocyanate used in the present invention may be any of those commonly used in urethane foams and is not particularly limited. For example, 2,4-tolylene diisocyanate and 2,6- The isomer ratio of tolylene diisocyanate, 2,4-tolylene diisocyanate and 2,6-tolylene diisocyanate is 80/20 (TDI-
80), a mixture of 65/35 (TDI-65), crude tolylene diisocyanate, biphenyl-4,4'-diisocyanate, diphenylmethane-4,4'-diisocyanate,
Polyphenylmethylene polyisocyanate (known as crude MDI, regardless of its production method), various known modified diphenylmethane-4,4'-diisocyanates modified with carbodiimide groups, and dianisidine diisocyanate. , Toluidine diisocyanate, xylylene diisocyanate, bis (2-isocyanatoethyl) fumarate, bis (2-isocyanatoethyl) carbonate, 1,6-hexamethylene diisocyanate, 1,4
-Tetramethylene diisocyanate, 1,10-decamethylene diisocyanate, cumene-2,4-diisocyanate, 4-methoxy-1,3-phenylene diisocyanate, 4-bromo-1,3- Phenylene diisocyanate, 4-ethoxy-1,3-phenylene diisocyanate, 2,4'-diisocyanato diphenyl ether,
5,6-dimethyl-1,3-phenylene diisocyanate, 2,4-dimethyl-1,3-phenylene diisocyanate, 2,4'-diisocyanato diphenyl ether,
Bis-5,6- (2-isocyanatoethyl) bicyclo [2,2,1] hept-2-ene, benzidine diisocyanate, 4,6-dimethyl-1,3-phenylene diisocyanate, 9, 10-anthracene diisocyanate, 4,4'-diisocyanatodibenzyl, 3,3'-
Dimethyl-4,4'-diisocyanatodiphenylmethane, 2,6-dimethyl-4,4'-diisocyanatodiphenyl, 2,4-diisocyanatostilbene, 3,3 '
-Dimethyl-4,4'-diisocyanatodiphenyl,
1,4-anthracene diisocyanate, 2,5-fluorange isocyanate, 1,8-naphthalene diisocyanate, 1,5-naphthalene diisocyanate, cumene-2,4-diisocyanate, 2,6- Obtained from diisocyanatobenzfuran, 2,4,6-tolylenetriisocyanate, dimers and trimers of these polyisocyanates, these organic polyisocyanates and the above-mentioned compounds having active hydrogen. It is a prepolymer having NCO groups at the molecular terminals, and these are used alone or in combination. The amount of the organic polyisocyanate used (including the amount used for the preparation of the urethane prepolymer) is not particularly limited, but in addition to the above polyol component, an amine compound that is appropriately used as a crosslinking agent in the urethane foam and active hydrogen containing water. Equivalent ratio of isocyanate group to compound (including OH group) (N
CO / H equivalent ratio) is 0.7 to 1.4, preferably 0.8 to
A range of 1.1 is appropriate.

In the method of the present invention, the flexible urethane foam is a polyol composition, a foaming agent, a foam stabilizer, other auxiliaries and an organic polyisocyanate in the presence of a trimerization catalyst which is used as a mixture with a urethane-forming catalyst. It is manufactured by reacting. As the catalyst for promoting the trimerization of the organic polyisocyanate, one known as a trimerization catalyst is used. That is, quaternary ammonium compounds such as benzyltrimethylammonium hydroxide, N-hydroxypropyltrimethylammonium salts of formic acid and other onium compounds, alkali metal hydroxides such as potassium hydroxide, alkaline metal alkoxides such as sodium methoxide, Alkali metal salts of carboxylic acids, especially saturated aliphatic monocarboxylic acids having 1 to 12 carbon atoms, such as sodium acetate, potassium acetate, potassium-2-ethylhexoate, potassium adipate, and sodium benzoate, tertiary amines. , N, N ′, N ″ -tris (dimethylaminopropyl) hexahydro-S-triazine, and the like.
The trimerization catalyst is used in an amount sufficient to provide the required reactivity and foam flexibility. The trimerization catalyst is 100 parts by weight of the polyol composition (hereinafter, "parts" means "parts by weight").
It is used in an amount of 0.005 to 5.0 parts, preferably 0.01 to 1.0 parts, and more preferably 0.05 to 0.5 parts. The urethane foam becomes more flexible with increasing amount of trimerization catalyst.

The urethanization catalyst that can be used in the present invention is not particularly limited as long as it has been conventionally used in the production of urethane foam. For example, an amine-based urethanization catalyst (triethylamine, triethylamine, triethylamine Propylamine, triisopropanolamine, trioctylamine, tributylamine, hexadecyldimethylamine, N-methylmorpholine, N-ethylmorpholine, N-octadecylmorpholine, monoethanolamine, diethanolamine, triethanolamine, N
-Methyldiethanolamine, N, N-dimethyldiethanolamine, diethylenetriamine, N, N, N ',
N'-tetramethylethylenediamine, N, N, N ',
N'-tetramethylpropylenediamine, N, N,
N ', N'-tetramethylbutanediamine, N, N,
N ', N'-tetramethyl-1,3-butanediamine,
N, N, N ', N'-tetramethylhexamethylenediamine, bis [2- (N, N-dimethylamino) ethyl]
Ether, N, N-dimethylbenzylamine, N, N
-Dimethylcyclohexylamine, N, N, N ',
N ', N'-pentamethyldiethylenetriamine, triethylenediamine, triethylenediamine formate and other salts, oxyalkylene adducts of primary and secondary amines, aza compounds such as N, N-dialkylpiperazine, various N, N ', N'-trialkylaminoalkylhexahydroxytriazines, JP-B-52-4
No. 3517 β-aminocarbonyl catalyst, Japanese Examined Patent Publication No. 53-
14279 β-aminonitrile catalyst, JP-A-59-
No. 191743 primary amine carbonates, etc.), organometallic urethane forming catalysts (tin acetate, tin octylate, tin oleate, tin laurate, dibutyltin dilaurate, dibutyltin dichloride, lead octanoate, lead naphthenate). , Nickel naphthenate, cobalt naphthenate, etc.). The amount of urethanization catalyst used is 100 parts per 100 parts of the polyol composition.
It is 001 to 5.0 parts, preferably 0.01 to 5.0 parts. In the present invention, the amount of water used as a foaming agent is 1 to 10 parts, preferably 2 to 7 parts, based on 100 parts of the polyol composition. Outside this range, the effect of softening the urethane foam becomes small. In the present invention, the blowing agent is basically only water, but other blowing agents may be used together. Among such blowing agents are trichloromonofluoromethane, dichlorodifluoromethane, methylene chloride, trichlorotrifluoroethane, dibromotetrafluoroethane, trichloroethane, pentane, n-hexane, dichlorotrifluoroethane, 1,1-dichloro- 1-fluoroethane, 2,2-dichloro-1,1,1
-Halogenated hydrocarbon-based substances including trifluoroethane and the like are preferably prevented from being released to the outside as they are.

The foam stabilizer in the present invention is a conventionally known organosilicon surfactant, for example, L-520, L-532, L-540, L-544, L manufactured by Nippon Unicar Co., Ltd.
-550, L-355, L-5305, L-5307,
L-5309, L-5710, L-5720, L-57
40M, L-6202, etc., and SH-190, SH-192, SH-194, SH manufactured by Toray Silicone Co., Ltd.
-200, SRX-253, SRX-274c, SF-
2961, SF-2962, SRX-280A, SRX
-294A and the like, and F-11 manufactured by Shin-Etsu Silicone Co., Ltd.
4, F-121, F-122, F-220, F-23
0, F-258, F-260B and the like, and B-4113 and the like manufactured by Gold Schmidt. The amount of these foam stabilizers used is 0.1 to 100 parts by weight of the polyol composition.
It is 10.0 parts, preferably 0.1 to 5 parts. The present invention may contain auxiliary agents such as paints, colorants, flame retardants, and fillers, if necessary. The flexible urethane foam of the present invention can be produced by a conventional method, a batch method or a continuous method, without any particular limitation. The flexible urethane foam obtained by the present invention has excellent flexibility.

[0013]

EXAMPLES Next, the present invention will be described more specifically by way of Examples and Comparative Examples. The meanings of the abbreviations used in Examples and Comparative Examples are as follows. Polyol a (Specific Example of Polyol A) Glycerin with propylene oxide, ethylene oxide,
Addition polymerization of propylene oxide in this order, ethylene oxide content 15 mol%, hydroxyl number 5
Polyether polyol with 6 mgKOH / g and a primary hydroxyl group concentration of 10% by weight. Polyol b (Comparative Example of Polyol A) Hydroxyl number 56 mgKOH / obtained by addition-polymerizing propylene oxide and ethylene oxide in this order on glycerin
g of polyether polyol. TEDA Triethylenediamine DMEA N, N-Dimethylethanolamine R-141 (trimerization catalyst) N, N ', N "-tris (dimethylaminopropyl) hexahydro-S-triazine sold by Active Material Chemical Co. Dabco-TMR (trimerization catalyst) 2-Hydroxypropyltrimethylammonium-2-ethylhexoeye sold by Air Products
To. L-5740S Silicone foam stabilizer made by Nippon Unicar. TDI-80 2,4- Tolylene diisocyanate 80% by weight and 2,6-
A mixture of 20% by weight of tolylene diisocyanate.

Comparative Example 1 Polyol b 280 parts, water 14.0 parts, TEDA 0.28
Part, DMEA 0.42 part, and L-5740S 3.36 part were mixed in advance, stanas octoate 0.28 part was added thereto, TDI-80 156.4 part was immediately added after high speed mixing, and further high speed mixing was performed, and the temperature was adjusted to 40 ° C in advance. It was poured into a mold having an inner size of 400 × 400 × 70 mm, and the lid was closed to foam. In an oven at 160 ° C
After heat curing for 12 minutes, the urethane foam was taken out of the mold. The physical properties and cure properties of the obtained urethane foam were measured, and the results are shown in Table 1.

Comparative Examples 2-4, Examples 1-7 Polyol a, Polyol b, R-1 in the amounts shown in Table 1
No. 41, Dabco-TMR was used and treated in the same manner as in Comparative Example 1. The physical properties of the obtained flexible urethane foam were measured, and the results are shown in Table 1. The results of Examples 1 to 7 are
Compared with the results of Comparative Examples 1 to 4, it can be seen that the hardness of the urethane foam is dramatically reduced by using the polyol a in an amount of 30% by weight or more and using the trimerization catalyst and the urethanization catalyst in combination.

[0016]

In the method of the present invention, by using a polyol composition containing Polyol A and a trimerization catalyst and a urethanization catalyst as catalysts, it is possible to use only water without using halogenated hydrocarbons. It has an excellent effect of obtaining a flexible urethane foam.

[0017]

[Table 1]

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification number Reference number within the agency FI Technical indication C08G 101: 00) C08L 75:04 (72) Inventor Hisa Abe 1190 Kasamacho, Sakae-ku, Yokohama-shi, Kanagawa Address Mitsui Toatsu Chemical Co., Ltd. (72) Inventor Masahiro Yoneyama 1190 Kasama-cho, Sakae-ku, Yokohama-shi, Kanagawa Mitsui Toatsu Chemical Co., Ltd.

Claims (6)

[Claims] 1. A polyol composition is reacted with an organic polyisocyanate in the presence of a foaming agent, a foam stabilizer and a catalyst,
In manufacturing a flexible urethane foam, at least one of the polyol compositions has an average number of functional groups of 2.5 to 3.0.
It is a type in which ethylene oxide is added to the inside of the molecule and propylene oxide is added to the end of the molecule, the primary hydroxyl group concentration is 15% by weight or less, the hydroxyl value is 30 to 100 mgKOH / g,
A polyether polyol having an ethylene oxide content of 5 to 30 mol% (hereinafter referred to as polyether A),
A method for producing a flexible urethane foam, characterized in that the proportion of the polyol A is 30% by weight or more of the polyol composition and a mixture of a trimerization catalyst and a urethanization catalyst is used as a catalyst. 2. The polyol composition is one kind or a mixture of two or more kinds selected from the group consisting of polyether polyols, polymer polyols, polyester polyols, and ring-opening polymers of cyclic esters. Manufacturing method of flexible urethane foam. 3. The method for producing a flexible urethane foam according to claim 1, wherein the polyol composition has a hydroxyl value of 20 to 150 mgKOH / g. 4. The organic polyisocyanate is tolylene diisocyanate, diphenylmethane diisocyanate, polymethylene polyphenyl polyisocyanate, and one or each of these organic polyisocyanates and the polyol composition according to claim 2. The production of a flexible urethane foam according to claim 1, which is one kind or a mixture of two or more kinds selected from the group consisting of an isocyanate-excessive prepolymer having an NCO group at a molecular end obtained by a reaction with one or more kinds of compounds. Method. 5. The equivalent ratio of the isocyanate groups of the organic polyisocyanate to the active hydrogen in the reaction solution is 0.7: 1.0 to 1.4.
The method for producing a flexible urethane foam according to claim 1, wherein: 1.0. 6. The method for producing a flexible urethane foam according to claim 1, wherein one kind or two or more kinds selected from the group consisting of an amine catalyst and / or an organometallic urethane catalyst is used as the urethane catalyst.