JP3418473B2 - Method for producing polyoxyalkylene polyol - 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 flexible polyurethane foam mainly used for vehicle cushions and a method for producing a polyoxyalkylene polyol used for producing the flexible polyurethane foam.

[0002]

2. Description of the Related Art Permanent compression strain is important as a physical property required for a flexible polyurethane foam as a cushion material. Particularly in the case of cushioning for vehicles, if this characteristic is inferior, the thickness of the seat cushion will decrease over time, and this will cause a problem because the position of the eyes of the vehicle driver (so-called eye point) will change. Cause aggravation.

In order to improve the permanent compression set of flexible polyurethane foams, many studies have been made in the past. Generally, a method of increasing the number of functional groups of the polyoxyalkylene polyol or a method of increasing the degree of crosslinking of the flexible polyurethane foam by using a polyfunctional crosslinking agent having a low molecular weight can be mentioned. The method for producing a polyoxyalkylene polyol is
Japanese Patent Laid-Open No. 02-115211, Japanese Patent Laid-Open No. 03-06862
0, USP 5,093,380. In this method, polyoxyalkylene polyol with low total unsaturation derived from side reactions during propylene oxide polymerization, that is, low monool content, was synthesized using a metal complex catalyst, and permanent compression strain of flexible polyurethane foam was obtained. Attempts have been made to improve. The principle of the invention is such that the monool content of the polyoxyalkylene polyol is decreased and the average number of functional groups is increased, and as a result, the degree of crosslinking of the flexible polyurethane foam using the polyoxyalkylene polyol is increased and the flexible polyurethane is It can be considered that the permanent compression set of the foam is improved. However, it is clear that in such a method, the elongation, which is a mechanical property required for the soft polyurethane resin, is lowered. Further, regarding the copolymer of propylene oxide and allyl glycidyl ether, USP
The description can be found in the examples of 3,941,849 and USP 3,829,505. The present invention relates to a method for polymerizing alkylene oxide with a metal complex catalyst,
Propylene oxide 9 as an example of polymerization with a different monomer
A polyoxyalkylene polyol added with a metal complex catalyst in a ratio of 7% by weight and 3% by weight of allyl glycidyl ether is described. However, there is no description about copolymerization using an alkali metal hydroxide catalyst such as potassium hydroxide or cesium hydroxide, and no description about physical properties of a flexible polyurethane foam using a copolymer polyoxyalkylene polyol. Currently, there is a demand for a method for producing a flexible polyurethane foam that improves the permanent compression strain of the flexible polyurethane foam and does not reduce the elongation.

[0004]

An object of the present invention is to provide a method for producing a polyoxyalkylene polyol, and by using the polyoxyalkylene polyol, the permanent compression strain is small and the elongation is not lowered. It is to provide a method for producing a flexible polyurethane foam.

[0005]

As a result of various investigations, the present inventors have found that in addition to the alkylene oxide conventionally used in the production of polyoxyalkylene polyols, allyl glycidyl ether is used to form a side chain. It has been found that the object can be achieved by synthesizing a polyoxyalkylene polyol having a heavy bond introduced therein and using the polyoxyalkylene polyol to produce a flexible polyurethane foam.

That is, the gist of the present invention is a method for producing a polyoxyalkylene polyol by adding an alkylene oxide to an active hydrogen compound in the presence of an alkali metal hydroxide catalyst, wherein 99.9 to 90% by weight of the alkylene oxide is added. And 0.1 to 10% by weight of allyl glycidyl ether are added, wherein the total amount of ethylene oxide used as alkylene oxide does not exceed 30% by weight. A method for producing a polyoxyalkylene polyol, characterized in that the amount of ethylene oxide used for the end cap of the alkylene polyol is 5% by weight or more.
A flexible polyurethane foam obtained by reacting a mixture of a foaming agent, a catalyst, a foam stabilizer, and a cross-linking agent with a polyisocyanate, wherein the polyoxyalkylene polyol of the present invention 1 is used as a matrix polyol, and an ethylenically unsaturated monomer compound A method for producing a flexible polyurethane foam in which polymer fine particles obtained by radical polymerization are dispersed, and a polymer polyol having a polymer concentration of 1 to 60% by weight is used, which comprises a polyoxyalkylene polyol, a foaming agent, In a flexible polyurethane foam obtained by reacting a mixture of a catalyst, a foam stabilizer, and a cross-linking agent with a polyisocyanate, the same polyoxyalkylene polyol as the polyoxyalkylene polyol of the present invention or a conventionally known polyoxyalkylene polyol is used. And A method for producing a flexible polyurethane foam, which comprises using a polymer polyol in which fine polymer particles obtained by radical polymerization of a renically unsaturated monomer compound are dispersed and having a polymer concentration of 1 to 60% by weight. .

Examples of the active hydrogen compound include dihydric alcohols such as ethylene glycol, propylene glycol and 1,4-butanediol, polyhydric alcohols such as glycerin, trimethylolpropane and pentaerythritol, sorbitol, sugar and methyl. Examples include sugars such as glucosides, aliphatic amines such as ethylenediamine, aromatic amines such as toluylenediamine and diphenylmethanediamine, alkanolamines such as triethanolamine and diethanolamine, phenols such as bisphenol A and novolac, and water. To be Further, compounds obtained by adding alkylene oxide to these active hydrogen compounds by a conventionally known method can also be used as active hydrogen.

The alkylene oxide is an alkylene oxide which has been conventionally used and includes ethylene oxide, propylene oxide, butylene oxide and the like, and they are used alone or in combination, and propylene oxide and ethylene oxide are particularly preferable. .

The polyoxyalkylene polyol refers to any molecular weight having a functional number of 2 to 8 obtained by adding an alkylene oxide to an active hydrogen compound. For the purpose of the present invention, one functional group of the active hydrogen compound is used. It is desirable to add 100 to 28 mol, preferably 97 to 30 mol of alkylene oxide. Further, for the purpose of the present invention, when the total amount of ethylene oxide, which is an alkylene oxide, exceeds 30% by weight, the permanent compression strain is lowered, and when the amount of ethylene oxide used for the end cap is less than 5% by weight, the curing property of the foam is remarkably deteriorated. Not preferred because of

The amount of allyl glycidyl ether used is 9
9.9 to 90% by weight of alkylene oxide,
0.1 to 10% by weight, preferably 99.7 to 9
0.3-8 for 2% by weight of alkylene oxide
%, Most preferably 0.5 to 5% by weight, based on 99.5 to 95% by weight of alkylene oxide. The amount of allyl glycidyl ether used is 0.1% by weight
The effect of improving the permanent compression strain cannot be expected in a flexible polyurethane foam using a polyoxyalkylene polyol of less than 1%. The amount of allyl glycidyl ether used is 1
If it exceeds 0% by weight, the viscosity of the obtained polyoxyalkylene polyol increases and it cannot be used.

Regarding the mode of addition of the allyl glycidyl ether, it may be added in blocks, or may be added randomly at the same time as the alkylene oxide such as propylene oxide. For example, propylene oxide is added, the reaction is completed, and then allyl glycidyl ether is added to obtain a block adduct, and propylene oxide and allyl glycidyl ether are mixed or alternately charged into the reactor. Then, a random copolymer is obtained by synthesizing a polyoxyalkylene polyol. Further, a polymerizable unsaturated group-containing epoxy compound other than allyl glycidyl ether can also be used for this purpose.

The reaction of adding an alkylene oxide to an active hydrogen compound in the presence of an alkali metal hydroxide catalyst is
Reaction temperature 60 to 150 ° C., pressure 0.5 to 9 kg / cm ²
The condition of (150 to 980 kPa) is preferably used. Usually, the alkylene oxide is continuously charged into the reactor, but after the charging of the alkylene oxide is completed, an operation of maintaining the temperature and reacting the alkylene oxide is performed.

The alkali metal hydroxide catalyst refers to sodium hydroxide, potassium hydroxide, cesium hydroxide and the like, but potassium hydroxide and cesium hydroxide are particularly preferable.
The alkali metal hydroxide catalyst is preferably used in the range of 0.05 to 0.5 mol with respect to 1 mol of the active hydrogen compound as an initiator.

After completion of the reaction, water and mineral acids such as hydrochloric acid and phosphoric acid or organic acids such as acetic acid are added to the reaction solution, dehydrated and dried, and the precipitated catalyst salt is removed by filtration. The polyoxyalkylene polyol obtained by removing the catalyst by a conventionally known method such as an adsorption removal method for treatment, a water washing removal for extracting the catalyst from the reaction solution using water or water and an organic solvent, and an ion exchange method using an ion exchange resin. To get

As a method for producing a flexible polyurethane foam, a conventionally known method is used.
A mixture of the polyoxyalkylene polyol obtained by the above method and a polymer polyol having a polymer concentration of 1 to 60% by weight obtained by radical polymerization of an ethylenically unsaturated monomer compound in the polyoxyalkylene polyol is used as a polyol component. , Water as a foaming agent, a silicone surfactant as a foam stabilizer, a catalyst, a cross-linking agent and, if necessary, a flame retardant, a resin premix prepared by mixing an auxiliary agent such as a pigment, and a polyisocyanate. It is produced by mixing. 2,4 for polyisocyanate
A mixture of toluylene diisocyanate and 2,6-toluylene diisocyanate in a weight ratio of 80:20 (TDI-
80/20) or TDI-80 / 20 and so-called polymeric MDI (4,4'- or 2,4 ')
A mixture of diphenylmethane diisocyanate, a trinuclear or more methylene-bridged polyphenyl polyisocyanate and a mixture thereof in a weight ratio of 80:20 is mainly used, and a urethane modified product and a carbodiimide modified product of diphenylmethane diisocyanate are used. Etc. are also used.

The resin premix and the polyisocyanate are mixed in a low-pressure or high-pressure foaming machine and, if necessary, filled in a mold to produce a flexible polyurethane foam molded product.

The polymer polyol is usually AIBN.
Was obtained by radically polymerizing ethylenically unsaturated monomers such as acrylonitrile and styrene at 60 to 200 ° C. in a polyoxyalkylene polyol in the presence of a radical initiator such as , Polymer fine particles dispersed in a polyoxyalkylene polyol. The polymer concentration in the polymer polyol is adjusted by appropriately changing the addition amount of the ethylenically unsaturated monomer. In the present invention, when a polymer polyol obtained from a conventionally known polyoxyalkylene polyol is used, the polyoxyalkylene polyol (A) of the present invention and the polymer polyol (B) having a polymer concentration of 1 to 60% by weight are used. (A) :( B) = 99: 1 to 20: 8
It is preferable to use it in a weight ratio of 0. When the allyl glycidyl ether copolymer used in the present invention is used as the polyoxyalkylene polyol used as the matrix of the polymer polyol, the dispersion stability of the polymer fine particles obtained by radically polymerizing the ethylenically unsaturated compound in the polymer polyol is improved. It has good properties and is used for
Is preferably used as the polymer polyol for the flexible urethane foam.

The blowing agent used in the present invention is water, trichloromonofluoromethane, dichlorodifluoromethane, 2,
2-dichloro-1,1,1-trifluoroethane, 1,
1-dichloro-1-fluoroethane, methylene chloride, trichlorotrifluoroethane, dibromotetrafluoroethane, trichloroethane, pentane, n-hexane and the like are one kind or a mixture of two or more kinds. As an example, water is ion-exchanged water or distilled water, and the amount used is preferably 1 to 10 parts by weight based on 100 parts by weight of the compound having active hydrogen.

The foam stabilizer used in the present invention is a conventionally known organic silicon surfactant, for example, L-520, L-532, L-540, L-544 and L manufactured by Nippon Unicar Co., Ltd.
-550, L-3550, L-5305, L-360
0, L-3601, L-5305, L-5307, L-
5309, L-5710, L-5720, L-5740
S manufactured by Torre Dow Corning, such as M and L-6202
H-190, SH-194, SH-200, SPX-2
53, SRX-274C, SF-2961, SF-29
62, SPX-280A, SPX-294A and the like, F-114, F-121, F-122 manufactured by Shin-Etsu Silicone Co., Ltd.
F-220, F-230, F-258, F-260B,
F-317, F-341, F-601, F-606, X
-20-200, X-20-201 and the like, TFA-4200 and TFA-4202 and the like manufactured by Toshiba Silicone, and B-4113 and the like manufactured by Goldschmidt. The foam stabilizer may be used in an amount of about 0.1 to 10 parts by weight based on 100 parts by weight of the compound having active hydrogen.

The urethanization reaction catalyst used in the present invention is conventionally known and is not particularly limited. For example, as the amine-based catalyst, triethylamine, tripropylamine, polyisopropanolamine, tributylamine,
Trioctylamine, hexamethyldimethylamine, N
-Methylmorpholine, N-ethylmorpholine, N-octadecylmorpholine, monoethanolamine, diethanolamine, triethanolamine, N-methyldiethanolamine, N, N-dimethylethanolamine, diethylenetriamine, N, N, N ', N'-tetra Methylethylenediamine, 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′-pentamethyldiethylenetriamine, triethylenediamine, triethylenediamine formate and other Salts, oxyalkylene adducts of amino groups of primary and secondary amines, aza ring compounds such as N, N-dialkylpiperazines, various N, N ',
N ″ -trialkylaminoalkylhexahydrotriazines, β-aminocarbonyl catalyst described in JP-B-52-43517, β-amino compound disclosed in JP-B-53-14278
An amino nitrile catalyst etc. are mentioned. Further, as the organometallic catalyst, tin acetate, tin octylate, tin oleate,
Examples thereof include tin laurate, dibutyltin diacetate, dibutyltin dilaurate, dibutyltin dichloride, lead octanoate, lead naphthenate, nickel naphthenate, and cobalt naphthenate. These catalysts may be used alone or in combination of two or more, and the amount of the catalyst used may be the compound 100 having active hydrogen.
It is 0.0001 to 10.0 parts by weight with respect to parts by weight.
As an example, active material chemical company amine catalyst L-102
0, organometallic catalyst MINICO TMDA, etc.

The cross-linking agent used in the present invention is ethylene glycol, propylene glycol, diethylene glycol,
Monoethylene polyols such as triethylene glycol, 1,3-butanediol and 1,4-butanediol, alkanolamines such as triethanolamine and diethanolamine, aliphatic polyamines such as ethylenediamine and diethylenetriaminetriethylenetetramine, and methylene orthochlor. Amine, 4,4'-diphenylmethanediamine, aniline, 2,4'-tolylenediamine, 2,
Aromatic polyamines such as 6'-tolylenediamine, and hydroxyl values of 200 m obtained by adding ethylene oxide, propylene oxide or the like to these active hydrogen compounds.
It is a compound of gKOH / g or more. In addition, hydroquinone, resorcin, aniline, etc., ethylene oxide,
Hydroxyl value 2 obtained by adding propylene oxide, etc.
A compound of 00 mgKOH / g or more can also be used. The amount used is preferably 1 to 10 parts by weight. Examples include polyol KL-210 manufactured by Mitsui Toatsu Chemicals, Inc.

The addition of other conventionally known auxiliary agents such as pigments and flame retardants does not impair the gist of the present invention.

[0023]

EXAMPLES Examples of the present invention will be shown below to clarify aspects of the present invention. The analysis of polyoxyalkylene polyol was performed according to JIS K-1577. Cesium hydroxide is a product of Chemetal (cesium purity 99.9
%) Was used in the form of a 50% aqueous solution. The composition of potassium hydroxide (manufactured by Nippon Soda Co., Ltd.) was a solid substance having a KOH content of 96% by weight. 1. Production Example 1 of Polyoxyalkylene Polyol (hereinafter abbreviated as polyol) Example 1 Glycerin was used as an active hydrogen compound (initiator), a cesium hydroxide catalyst was added, and dehydration under reduced pressure was performed at 105 ° C. for 6 hours (water content: 0.1 wt% or less). . Maximum pressure after nitrogen purging 4
propylene oxide and allyl glycidyl ether were added at a reaction temperature of 95 ° C. at kg / cm ² (490 kPa),
Then, the maximum pressure was 4.4 kg / cm ² (530 kP
a), adding ethylene oxide at a reaction temperature of 105 ° C.,
The reaction was performed at the ratio shown in Table 1. After the completion of the reaction, the crude polyol containing the obtained catalyst was purified by adding water and hydrochloric acid, and drying the precipitated hydrochloride of the catalyst by filtration.
The target hydroxyl value of the obtained polyol is 24 mgKOH /
It was g.

Example 2 Glycerin was used as an active hydrogen compound (initiator), a cesium hydroxide catalyst was added, and dehydration under reduced pressure was performed at 105 ° C. for 6 hours (water content: 0.1 wt% or less). Maximum pressure after nitrogen purging 4
kg / cm ² (490 kPa) at a reaction temperature of 95 ° C., a mixed solution of propylene oxide and allyl glycidyl ether was added, and then the maximum pressure was 4.4 kg / cm ² (530
kPa), ethylene oxide was added at a reaction temperature of 105 ° C., and the reaction was performed at the ratio shown in Table 1. After completion of the reaction, the crude polyol containing the obtained catalyst was purified by adding water and hydrochloric acid,
After drying, the hydrochloride of the catalyst deposited was removed by filtration. The target hydroxyl value of the obtained polyol is 24 mg KO
It was H / g.

Example 3 Using glycerin as an active hydrogen compound (initiator), a potassium hydroxide catalyst was added and dehydration was carried out under reduced pressure at 105 ° C. for 6 hours (water content: 0.1 wt% or less). Maximum pressure after nitrogen purging 4
propylene oxide and allyl glycidyl ether were added at a reaction temperature of 95 ° C. at kg / cm ² (490 kPa),
Then, the maximum pressure was 4.4 kg / cm ² (530 kP
a), adding ethylene oxide at a reaction temperature of 105 ° C.,
The reaction was performed at the ratio shown in Table 1. After the completion of the reaction, the crude polyol containing the obtained catalyst was purified by adding water and hydrochloric acid, and drying the precipitated hydrochloride of the catalyst by filtration.
The target hydroxyl value of the obtained polyol is 24 mgKOH /
It was g.

Comparative Example 1 Glycerin was used as an active hydrogen compound (initiator), a potassium hydroxide catalyst was added, and dehydration under reduced pressure was performed at 105 ° C. for 6 hours (water content: 0.1 wt% or less). Maximum pressure after nitrogen purging 4
kg / cm ² (490 kPa) at a reaction temperature of 95 ° C., propylene oxide was added, and then the maximum pressure was 4.4 kg.
/ Cm ² (530 kPa) and a reaction temperature of 105 ° C., ethylene oxide was added, and the reaction was carried out at the ratio shown in Table 1.
After the completion of the reaction, the crude polyol containing the obtained catalyst was purified by adding water and hydrochloric acid, and drying the precipitated hydrochloride of the catalyst by filtration. The target hydroxyl value of the obtained polyol was 24 mgKOH / g.

Comparative Example 2 The reaction was carried out under the same operation and conditions as in Example 2. The charging ratio is as shown in Table 1.

2. Production of Polymer Polyol A 1 liter autoclave equipped with a thermometer, a stirrer, and a liquid feeder was charged with the polyol in a liquid-filled state, and the temperature was raised to 120 ° C. with stirring. A mixed solution of polyol, azobisisobutyronitrile (hereinafter abbreviated as AIBN), and acrylonitrile, which had been mixed in advance in a ratio shown in Table 2, was continuously charged, and a polymer polyol was continuously obtained from an outlet. . At this time, the reaction pressure is 3.5 kg / cm
² (440 kPa) and the residence time was 50 minutes. The obtained polymer polyol is 120 ° C., 20 mmHg
Unreacted monomer was removed by subjecting to (2.7 kPa) reduced pressure treatment for 4 hours. The results are shown in Table 2.

3. Foaming Evaluation Polyols obtained in Examples 1 to 3 and Comparative Examples 1 to 2 and the above-mentioned polymer polyols, foaming agents, crosslinking agents, catalysts,
The foam stabilizer and other additives were sufficiently stirred to form a resin premix, and the temperature was adjusted to 25 ° C. Cosmonate TM-20 manufactured by Mitsui Toatsu Chemical Co., Ltd. (TDI80 / 20 and Mitsui Toatsu Chemical Co., Ltd.) adjusted so that the equivalent ratio of NCO group and active hydrogen of resin premix was 1.00 and adjusted to 25 ° C. Cosmonate M-200 (so-called polymeric MD
The mixture of I) in a weight ratio of 80:20) and the resin premix prepared above are vigorously stirred and mixed for 6 seconds,
Aluminum test mold (400 mm × 400 mm × 100 mm) heated to 0 ° C and coated with a commercial release agent
After the injection, the lid was closed, the container was sealed with a clamp, and the mixture was cured for a predetermined time (for example, 6 minutes). Subsequently, the mold was removed from the mold, and compression by a crushing roll (for example, 80% compression) was repeated several times to obtain the desired flexible polyurethane foam.

In Examples 4 to 6 and Comparative Example 4, the desired flexible polyurethane foam was obtained by the above-mentioned operations and conditions. In Comparative Example 5, however, the resin premix had a high viscosity and was difficult to foam. No flexible polyurethane foam was obtained.

The raw material blending formulation and the physical properties of the obtained flexible polyurethane foam are as shown in Table 3. The general physical properties were measured according to JIS K-6301 or 6401.

[0032]

[Table 1] The unit of each oxide is wt%.

[0033]

[Table 2] <Note> The amount used is parts by weight. Polyol A: Polyol synthesized in Example 1 Polyol B: Polyol synthesized in Comparative Example 1

[0034]

[Table 3] KL-210: Cross-linking agent manufactured by Mitsui Toatsu Chemicals Inc. SRX-274C: Surfactant manufactured by Toray Dow Corning L-1020: Catalyst manufactured by Activator Chemical Co., Ltd. MINIKO TMDA: Catalyst manufactured by Activator Chemical Co., Ltd.

[0035]

EFFECTS OF THE INVENTION By using the polyoxyalkylene polyol of the present invention, it is possible to produce a flexible polyurethane foam having an improved permanent compression strain without a decrease in elongation.

─────────────────────────────────────────────────── --Continued front page (56) References JP-A-8-48763 (JP, A) JP-A-8-176258 (JP, A) JP-A-7-206961 (JP, A) JP-A-63- 126535 (JP, A) JP 62-250032 (JP, A) JP 45-12866 (JP, B1) (58) Fields investigated (Int.Cl. ⁷ , DB name) C08G 65/28 CA ( STN)

Claims (3)

(57) [Claims] 1. A method for producing a polyoxyalkylene polyol by adding an alkylene oxide to an active hydrogen compound in the presence of an alkali metal hydroxide catalyst,
9.9 to 90% by weight of alkylene oxide and 0.1 to
A method for producing a polyoxyalkylene polyol, which comprises adding 10% by weight of allyl glycidyl ether. 2. A method for producing a polyoxyalkylene polyol by adding an alkylene oxide to an active hydrogen compound in the presence of an alkali metal hydroxide catalyst,
9.7 to 92% by weight of alkylene oxide and 0.3 to
A method for producing a polyoxyalkylene polyol, which comprises adding 8% by weight of allyl glycidyl ether. 3. The total amount of ethylene oxide used as the alkylene oxide does not exceed 30% by weight, and the amount of ethylene oxide used for the end cap of the polyoxyalkylene polyol is 5% by weight or more. A method for producing the described polyoxyalkylene polyol.