JP3145758B2 - Urethane foam manufacturing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a polyurethane foam having improved physical properties, characterized by using a modified polyol compound. More specifically, the present invention relates to a method for producing a urethane foam having improved hardness by using a transparent and homogeneous polyol compound obtained by grafting a specific vinyl monomer having a metal ion to a polyol.

[0002]

2. Description of the Related Art As is well known, polyol compounds are widely used as raw materials for various urethane resins.
Urethane resins are used in a very wide range, and raw materials such as organic polyisocyanates and polyols to be used and molding conditions are selected depending on the use in order to adjust the physical properties of molded articles. Among them, the modification of the hardness of urethane foam is also an important issue. For example, in the case of a flexible foam, several methods are known for increasing the hardness of the foam. For example, the hardness is increased by increasing the number of functional groups of the polyol to be used and increasing the degree of crosslinking of the urethane resin. However, the most effective way to increase foam hardness is
9-24737, 41-347, 43-22108, 4
4-8230, 47-15108, 47-47597,
As described in JP 47-47998 and 47-47999, dispersion of ethylenic polymer particles dispersed in a polyol obtained by polymerizing an ethylenically unsaturated monomer in a polyol. In other words, a polymer polyol, which is a modified polyol, is used.

[0003]

However, the above polymer polyol is a dispersion of polymer particles of an ethylenically unsaturated monomer in the polyol. This is a major drawback in the resin molding system, as the viscosity of the body rises and normal operations such as feeding and mixing operations of raw materials using a pump become impossible.The hardness of the urethane foam is increased by using a low-viscosity polyol compound. It is desired to develop a method for causing this to occur.

[0004]

Means for Solving the Problems Accordingly, the present inventors have:
By using a polyol composition in which polymer particles of an ethylenically unsaturated monomer are grafted in a polyol molecule such as a polymer polyol, solid fine particles are introduced into the urethane resin, and the hardness is increased by the filler effect. We searched for a method other than the system to make it work. As a result, when introducing a polymerized structure of an ethylenically unsaturated monomer into a polyol molecule, a metal salt of an α, β-unsaturated carboxylic acid is used as the ethylenically unsaturated monomer, and this metal salt is used. By using a product that is homogeneously grafted with a polyol, it has been necessary to add a large amount of polymer particles of ethylenically unsaturated monomer until now. Can be achieved,
The present invention has been completed.

That is, the present invention is as follows. In the polyol, a compound represented by the general formula (1), (CH ₂ ） CRCO-) _n · M ^{n +} (wherein, R is hydrogen or an alkyl group having 1 to 5 carbon atoms, n is 2 or 3, and M is Α, β- which is obtained by polymerizing a metal salt of an α, β-unsaturated carboxylic acid at 135 to 200 ° C. in the coexistence of a peroxide. A method for producing a urethane foam, comprising using a transparent and homogeneous modified polyol compound in which a metal salt of an unsaturated carboxylic acid is grafted on the polyol molecule.

The metal salts of the α, β-unsaturated carboxylic acids of the general formula (1) used in the present invention include calcium acrylate, magnesium acrylate, barium acrylate, zinc acrylate, nickel acrylate and acrylic acrylate. Divalent or trivalent metal salts of acrylic acid such as aluminum acrylate, calcium methacrylate, magnesium methacrylate, barium methacrylate, zinc methacrylate,
Divalent or trivalent metal salts of methacrylic acid such as nickel methacrylate and aluminum methacrylate are used. These metal salts are used alone or as a mixture of two or more in some cases. As the polyol used in the present invention, ethylene glycol, glycerin,
An active hydrogen-containing compound such as pentaerythritol, sorbitol, sucrose, or an organic amine is used alone or in combination with one or more alkylene oxides such as ethylene oxide (EO), propylene oxide (PO), and butylene oxide (BO). Or a polyether polyol or a polymer of tetrahydrofuran (PTM)
EG) and polyester polyols can be used. Upon use, they are used as one kind or as a mixture of two or more kinds depending on the use.

The peroxides used as radical initiators in the present invention include octanoyl peroxide, decanoyl peroxide, lauroyl peroxide,
Benzoyl peroxide, diacyl peroxide such as m-toluyl peroxide, dioxydicarbonyl peroxide, peroxydicarbonate such as di-n-propyldicarbonyl peroxide, di-t-butyl peroxide, t-butyl Examples thereof include dialkyl peroxides such as cumyl peroxide, peroxyesters such as t-butylperoxyacetate, and hydroperoxides such as t-butylhydroperoxide.

[0008] The polymerization temperature of the present invention is 135-200 ° C,
Preferably it is 140-170 degreeC. When the polymerization temperature is lower than this range, graft addition of a metal salt of an α, β-unsaturated carboxylic acid to a polyol does not completely occur, and a polymer of a metal salt of an α, β-unsaturated carboxylic acid is precipitated. Also,
When the polymerization temperature is higher than this range, the thermal decomposition of the polyol occurs during the polymerization to deteriorate the physical properties of the urethane foam molded article, the decomposition rate of the radical initiator is extremely high, and the deactivation of the radical species is fast, and α, β- The reaction rate of the monomer of the unsaturated carboxylic acid metal salt decreases, and the remaining metal salt of the α, β-unsaturated carboxylic acid undergoes thermal polymerization at a high temperature to precipitate polymer particles.

The polyol compound prepared under the above-mentioned production conditions is obtained by subjecting a metal salt of an α, β-unsaturated carboxylic acid to thermal polymerization at an appropriate temperature and graft-polymerizing this saturated monomer to a polyol molecule. Because of this, the bond between the polyol and the polymer of the metal salt of the α, β-unsaturated carboxylic acid is good, and the polymer of the metal salt of the α, β-unsaturated carboxylic acid is a polyol like the conventional polymer polyol. It is a completely homogeneous liquid with no phase separation, unlike those physically mixed with. Therefore, even if the polymer itself is liquid at room temperature, it does not separate, and when molded into urethane foam, the effect of the functional group of the metal salt of α, β-unsaturated carboxylic acid is enhanced. Can be. A feature of the present invention resides in the use of a polyol compound as described above when producing a urethane foam, and the molding method can be based on all known methods.

That is, the production of urethane foam is performed by a known method. The raw material organic polyisocyanate includes (1) 2,4-tolylene diisocyanate,
6-Tolylene diisocyanate alone or 8 of these
0/20 weight ratio mixture (80 / 20-TDI), 65
/ 35 weight ratio mixture (65 / 35-TDI), crude tolylene diisocyanate (crude TD
(2) 4,4'-diphenylmethane diisocyanate (4,4'-MDI), 2,4'-diphenylmethane diisocyanate (2,4'-MDI), 2,2'- (3) hexamethylene diisocyanate, isophorone diisocyanate, dicyclohexyl methane diisocyanate, such as diphenylmethane diisocyanate (2,2'-MDI) or a mixture of these isomers, polymethylene polyphenyl polyisocyanate (crude MDI) For example, carbodiimide-modified, biuret-modified, dimer, trimer, and prepolymers of various polyols of (4) (1) to (3) are used. Polyisocyanates can be used alone or in mixtures, but polyisocyanates which are particularly suitable for the present invention are isomer mixtures of tolylene diisocyanates.

Examples of the crosslinking agent include (1) monomer polyols such as ethylene glycol, propylene glycol, diethylene glycol, triethylene glycol, dipropylene glycol, trimethylene glycol, 1,3- and 1,4-butanediol; 2) alkanolamines such as triethanolamine and diethanolamine, (3) aliphatic polyamines such as ethylenediamine, diethylenetriamine and triethylenetetramine, (4) methylene orthochloroaniline, 4,4'-diaminodiphenylmethane,
Addition of ethylene oxide and / or propylene oxide to aromatic polyamines such as aniline, 2,4-tolylenediamine and 2,6-tolylenediamine, and (5) various active hydrogen compounds of (1) to (4) Obtained hydroxyl number 20
Compounds of 0 mgKOH / g or more are used.

The equivalent ratio of the NCO groups in the organic polyisocyanate to the total amount of active hydrogen in the polyol and crosslinking agent (NCO
/ H) are made to react with each other under a quantitative ratio of the organic polyisocyanate, the polyol and the crosslinking agent such that the ratio becomes 0.70 to 1.40. As the catalyst, known catalysts are not particularly limited. For example, as an amine-based urethanization catalyst,
Triethylamine, tripropylamine, triisopropanolamine, tributylamine, hexadecyldimethylamine, N-methylmorpholine, N-ethylmorpholine, N-octadecylmorpholine, monoethanolamine, diethanolamine, triethanolamine, N-methyldiethanolamine, N, N-dimethylethanolamine, diethylenetriamine, N, N, N ', N'-tetramethylethylenediamine, N, N, N', N'-tetramethylpropylenediamine, N, N, N ', N'-tetramethylbutane Diamine, 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 ", N" -pentamethyldiethylenetriamine, triethylenediamine, salts of triethylenediamine, oxyalkylene adducts of amino groups of primary and secondary amines,
There are azacyclo compounds such as N, N-dialkylpiperazines, various N, N ', N "-trialkylaminoalkylhexahydrotriazines, β-aminonitrile catalysts described in JP-B-2-43517, and the like. Examples of the organometallic urethanization catalyst include tin acetate, tin octoate, tin oleate, tin laurate, dibutyl lead dichloride, lead naphthenate, nickel naphthenate, and cobalt naphthenate. Or a mixture of the active hydrogen-containing compounds in an amount of 0.0
01 to 10 is appropriate.

As the blowing agent, one or two kinds of water, trichloromonofluoromethane, dichlorodifluoromethane, methylene chloride, trichlorotrifluoroethane, dibromotetrafluoroethane, dichlorotetrafluoroethane, trichloroethane, pentane, n-hexane and the like are used. The above mixtures and the like are used. As the foam stabilizer, an organic silicon surfactant is suitable.
-520, L-532, SH-190, SH manufactured by Tre Silicon
-192, SRX-253. XF-2961, manufactured by Shin-Etsu Silicon,
F-114, F-121, F-122, TFA-4 manufactured by Toshiba Silicon Corporation
200, TFA-4202, Goldschmidt B-4113
Etc. The amount of the foam stabilizer used is 0.1 to 5 parts by weight based on 100 parts by weight of the total amount of the compound having active hydrogen and the organic polyisocyanate.

Further, if necessary, known stabilizers and fillers,
Use a coloring agent or the like. Usually, a mixture of predetermined amounts of a polyol, a crosslinking agent, a foam stabilizer, a catalyst, a foaming agent, and other auxiliaries is used as a resin component.

[0015]

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to Examples and Comparative Examples. Tables 1 and 2 collectively show Examples and Comparative Examples. Abbreviations in Examples and Tables are as follows. The number of parts in the examples is parts by weight. (PPG) A: To 1.7 parts of glycerin, 30 parts of propylene oxide was added, 13 parts of ethylene oxide was further added, and 55.3 parts of propylene oxide were further added, so that the hydroxyl value was 52 mgKOH /.
g of polyether polyol B: polyether polyol having a hydroxyl value of 56 mgKOH / g by adding propylene oxide to glycerin

(Monomer) MAA.Zn: Zinc methacrylate MAA.Mg: Magnesium methacrylate MAA.Al: Aluminum methacrylate

(Radical initiator) BPO: Benzoyl peroxide (containing 25% water) The analysis method of the obtained polyol compound is as follows. Hydroxyl value: OHV, according to JIS K-1557. Viscosity: The viscosity of the sample whose temperature was adjusted to 25 ° C. was measured using a Tokyo Keiki BM viscometer. Addition: Calculated from the following formula from the measured value of OHV. Addition (wt%) = ｛1- (OHV of polyol compound)
/ (OHV of PPG-A)｝ × 100

Reference Example 1 70 parts of PPG-A was charged into an autoclave, and the internal temperature was adjusted to 160 ° C. After the internal temperature was stabilized, a mixture of 36 parts of a 25% by weight aqueous solution of zinc methacrylate, 0.7 part of benzoyl peroxide (BPO), and 21 parts of PPG-A was fed while maintaining the internal temperature at 154 to 158 ° C. And charged into the autoclave. After sending the whole amount, the internal temperature was kept at 155 ° C. for another hour. After cooling the autoclave to room temperature, the contents were taken out, and water and by-products were removed by distillation under reduced pressure. The obtained polyol compound is a colorless uniform transparent liquid, the hydroxyl value is 47.2 mgKOH / g, and the viscosity is
It was 1,200 cps.

Reference Examples 2 and 3 Polyol compounds were prepared in the same manner as in Reference Example 1 except that zinc methacrylate was changed to magnesium methacrylate or aluminum methacrylate. Examples 1, 2, 3 50 parts of the polyol compound prepared in Reference Examples 1, 2, and 3,
50 parts of PPG-B, 5.5 parts of water, 0.3 parts of L-1020, N,
After uniformly mixing 0.1 part of N-dimethylethanolamine,
Further, add 0.1 part of tin laurate and stir, and further add 2,4-T
59 parts of an 80/20 mixture of DI and 2,6-TDI were added, stirred for 10 seconds, and charged into a mold to prepare a urethane foam. A 25% ILD was measured to determine the foam hardness.

Comparative Example 1 Instead of the polyol compound in Example 1, PPG-A5
A urethane foam was prepared in the same manner except that 0 part was used, and the hardness of the foam was determined. The hardness was significantly lower than in Examples 1, 2, and 3.

[0021]

[Table 1]

[0022]

[Table 2]

[0023]

According to the present invention, it is possible to prepare urethane foam having high hardness by a simple method.

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-3-81315 (JP, A) JP-A-3-81314 (JP, A) JP-A-61-2723 (JP, A) (58) Investigation Field (Int.Cl. ⁷ , DB name) C08G 18/63

Claims (1)

(57) [Claims] In a polyol, a compound represented by the general formula (1), (CH ₂ CRCOO-) _n · M ^{n +} (wherein, R is hydrogen or an alkyl group having 1 to 5 carbon atoms, and n is 2 or 3) Wherein M represents a divalent or trivalent metal ion) by polymerizing a metal salt of an α, β-unsaturated carboxylic acid at 135 to 200 ° C. in the presence of a peroxide. A method for producing a urethane foam, comprising using a transparent and homogeneous modified polyol compound in which a metal salt of an α, β-unsaturated carboxylic acid is grafted onto the polyol molecule.