JPH0912705A - Production of polyoxyalkylenepolyol - Google Patents

Abstract

PURPOSE: To obtain the subject high-molecular weight polyol by using a specific compound as a catalyst, more excellent in productivity than by a conventional method, useful for a nonrigid polyurethane foam. CONSTITUTION: When subjecting (B) an alkylene oxide (e.g. propylene oxide, etc.) to addition polymerization to (A) an active hydrogen compound containing 2 to 8 active hydrogens (e.g. glycerol), (C) at least one selected from the group consisting of rubidium carbonate cesium carbonate, rubidium hydrogencarbonate is used as a catalyst. For example, 3-200mol of the component B is used based on one functional group in the component A and 0.01-3mol of the component C is used based on 1mol of the component A. The reaction is carried out at 80-150 deg.C under 0.5-5kg/cm<2> .

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a method for producing a polyoxyalkylene polyol. Specifically, the present invention produces a polyoxyalkylene polyol by adding an alkylene oxide to an active hydrogen compound in the presence of at least one compound selected from the group consisting of rubidium carbonate, cesium carbonate, rubidium hydrogen carbonate and cesium hydrogen carbonate as a catalyst. On how to do. Polyoxyalkylene polyols are widely used as raw materials for polyurethane resins such as soft and rigid polyurethane foams, elastomers, paints, sealing materials, flooring materials and adhesives, and also as raw materials for surfactants.

[0002]

2. Description of the Related Art A polyoxyalkylene polyol is usually obtained by adding an alkylene oxide to an active hydrogen compound in the presence of an alkali metal hydroxide catalyst. Generally, potassium hydroxide is used as an alkali metal hydroxide catalyst, while continuously charging alkylene oxide into a reactor charged with an active hydrogen compound as a polymerization initiator,
Reaction temperature 80-150 ° C., pressure 0.5-5 kg / cm ²
The reaction is performed under the condition of (61 to 610 kPa) until a predetermined molecular weight is obtained to obtain a crude polyoxyalkylene polyol. Then, after neutralizing the potassium alcoholate in the crude polyoxyalkylene polyol with an aqueous solution of an acid such as a mineral acid or an organic acid, dehydration and drying, filtration of the precipitated potassium salt or the like, or washing of the crude polyoxyalkylene polyol with water, It is manufactured through a post-treatment purification step by drying.

As a catalyst used for producing a polyoxyalkylene polyol, Japanese Patent Publication No. 52-33000, which describes a method for purifying a polyoxyalkylene polyol, describes sodium carbonate, potassium carbonate, sodium hydrogen carbonate as an alkali metal catalyst. , Potassium hydrogen carbonate is mentioned. In addition, JP-A-60-21242, which describes a method for producing a polyoxyalkylene polyol.
In No. 5, alkali metal hydroxides and alkali metal carbonates are mentioned as catalysts used in the production of polyoxyalkylene polyols, and potassium or sodium hydroxides are particularly preferable. However, these catalysts are only listed as an example, and within the range investigated by the present inventors, when the addition polymerization of propylene oxide is carried out using the catalyst, an alkali represented by potassium hydroxide or the like is used. It was confirmed that the polymerization activity of propylene oxide was lower than that of the case of metal hydroxide.

Further, JP-A-56-43322 describes a method using an alkali metal compound salt and a crown ether and / or a cryptand. These catalysts such as crown ethers are extremely expensive as compared with potassium hydroxide, which is a general catalyst for producing polyoxyalkylene polyol, and are economically problematic in industrial use. In addition, since crown ether has toxicity, it is difficult to handle.

[0005]

DISCLOSURE OF THE INVENTION The object of the present invention is to improve the productivity of conventional alkali metal hydroxides and alkali metal carbonates, and also to provide high molecular weight polyoxy compounds used for flexible polyurethane foam applications and the like. It is to provide a method capable of producing an alkylene polyol.

[0006]

Means for Solving the Problems As a result of intensive studies for solving the above-mentioned object, the present inventors have found that at least one selected from the group consisting of rubidium carbonate, cesium carbonate, rubidium hydrogen carbonate and cesium hydrogen carbonate as a catalyst. I found that I should use.

That is, the present invention is selected from the group consisting of rubidium carbonate, cesium carbonate, rubidium hydrogen carbonate and cesium hydrogen carbonate as a catalyst when the alkylene oxide is addition-polymerized to an active hydrogen compound having 2 to 8 active hydrogens. It is a method for producing a polyoxyalkylene polyol using at least one compound, and the catalyst can be used by mixing with a compound composed of another alkali metal carbonate and an alkali metal hydrogen carbonate.

The method of the present invention will be described in detail below. The active hydrogen compound in the present invention has an active hydrogen number of 2 to
8 compounds, for example, dihydric alcohols such as ethylene glycol, propylene glycol and 1,4-butanediol, polyhydric alcohols such as glycerin, trimethylolpropane and pentaerythritol, saccharides such as sorbitol, sucrose and methyl glucoside, Examples thereof include fatty acid 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. These active hydrogen compounds may be used alone or in combination. Further, compounds obtained by adding alkylene oxide to these active hydrogen compounds by a conventionally known method can also be used as the active hydrogen compound used in the present invention.

Examples of the alkylene oxide in the present invention include ethylene oxide, propylene oxide, butylene oxide, styrene oxide and the like, and these are used alone or in combination.

The polyoxyalkylene polyol in the present invention is a compound having 2 to 8 hydroxyl groups, which is obtained by adding alkylene oxide to an active hydrogen compound. The molecular weight is not particularly limited, but it is 1 in active hydrogen compounds.
3 to 200 m of alkylene oxide with respect to the functional group
Those added in the range of ol are preferable.

The rubidium carbonate, cesium carbonate, rubidium hydrogen carbonate and cesium hydrogen carbonate in the present invention can be used alone or in combination. The above-mentioned at least one compound consisting of the alkali metal carbonate and the alkali metal hydrogen carbonate is used in the range of 0.01 to 3 mol per mol of the active hydrogen compound. Also,
Similar polymerization activity can be obtained even when used as a polymerization catalyst for alkylene oxide mixed with an alkali metal hydroxide.

The above-mentioned alkali metal carbonates and alkali metal hydrogencarbonates are used by adding them to active hydrogen compounds, but they may be used as solids or as aqueous solutions in any form. When the above alkali metal carbonate and alkali metal hydrogencarbonate are used in the form of an aqueous solution before adding the alkylene oxide to the mixture, it is desirable to perform dehydration treatment after mixing with the active hydrogen compound. When the alkali metal carbonate and alkali metal hydrogen carbonate are used as a solid form, dehydration treatment may be performed to remove a trace amount of water contained in the raw material, or the dehydration treatment may be performed without any treatment. You may use it.

The mixture thus obtained has a pressure of 0.5 to 5 kg in the temperature range of 80 ° C. to 150 ° C.
The alkylene oxide is polymerized so as to be in the range of / cm ² (61 to 610 kPa). Usually, the alkylene oxide is continuously charged to the reactor. After the charging of the alkylene oxide is completed, an operation of reacting the alkylene oxide while maintaining the temperature is performed. This operation is called internal pressure reaction, and the reaction is performed until the pressure decrease is no longer recognized. After reacting until the desired molecular weight is obtained, it is necessary to remove the catalyst used from the crude polyoxyalkylene polyol.

As a method for purifying the polyoxyalkylene polyol in the present invention, a conventionally known method can be used. An example is described below. Japanese Patent Publication 37-5
No. 597, Japanese Patent Publication No. 41-21237 and Japanese Patent Publication No. 47
A method of neutralizing an alkaline catalyst with an acid as described in JP-A-3745, etc., and removing a salt formed by filtration, JP-B-38-2615.
No. 8, Japanese Patent Publication No. 42-13021, Japanese Patent Publication No. 45-324
No. 32 and Japanese Patent Publication No. 45-33194 and the like, a method of neutralizing the catalyst or using an alkali adsorbent without neutralization, a method of dissolving in a specific solvent described in Japanese Patent Publication No. 49-14359 and washing with water. , JP-A-51-2321
A method using the ion exchange resin described in Japanese Patent No. 1 is mentioned.

In order to compare the performance of the alkylene oxide polymerization catalysts of the present invention, propylene oxide (hereinafter abbreviated as PO) is used as the alkylene oxide, and the reaction temperature and the pressure during the reaction are constant. The reaction time of PO until reaching the prescribed molecular weight below was measured. The molecular weight of polyoxypropylene polyol was evaluated by its hydroxyl value. The hydroxyl value is measured by JIS
According to the method of K-1557.

[0016]

EXAMPLES Examples of the present invention will be shown below to clarify aspects of the present invention, but the present invention is not limited to these examples. Example 1 Polyoxypropylene Polyol A 0.25 mol of cesium carbonate was added to 1 mol of glycerin, and vacuum dehydration treatment was performed at 105 ° C. for 3 hours.
200 g of this compound was charged into an autoclave equipped with a thermometer, a pressure gauge and a stirrer, and after purging with nitrogen, the maximum pressure was 4 kg / cm ² (490 kPa) and the reaction temperature was 11
Under the condition of 0 ° C., 7300 g of propylene oxide was charged and the reaction was carried out. After the charging of propylene oxide was completed, the reaction was continued until no pressure decrease was observed. The time required from the start of charging propylene oxide to the end of the reaction was 700 minutes. The hydroxyl value of this product is 33.
mg KOH / g.

Example 2 Polyoxypropylene Polyol B 0.30 mol of cesium carbonate and 0.10 mol of cesium carbonate hydroxide were added to 1 mol of glycerin, and 10 parts were added.
A vacuum dehydration treatment was performed at 5 ° C. for 3 hours. 234 g of this compound was charged into an autoclave equipped with a thermometer, a pressure gauge and a stirrer, and after purging with nitrogen, the maximum pressure was 4 kg /
The reaction was carried out by charging 7300 g of propylene oxide under the conditions of cm ² (490 kPa) and a reaction temperature of 110 ° C. After the charging of propylene oxide was completed, the reaction was continued until no pressure decrease was observed. The time required from the start of charging propylene oxide to the end of the reaction was 650 minutes. The hydroxyl value of this product is 32 mgKOH /
g.

Example 3 Polyoxypropylene Polyol C 0.20 mol of cesium carbonate and 0.10 mol of rubidium carbonate were added to 1 mol of glycerin, and 105
A vacuum treatment was carried out at 0 ° C for 3 hours. This compound was placed in an autoclave equipped with a thermometer, pressure gauge and stirrer.
Maximum pressure 4kg / cm
² (490 kPa) and 7300 g of propylene oxide were charged under the reaction temperature of 110 ° C. to carry out the reaction. After the charging of propylene oxide was completed, the reaction was continued until no pressure decrease was observed. The time required from the start of propylene oxide charging to the end of the reaction was 730 minutes.
The hydroxyl value of this product was 34 mgKOH / g.

Example 4 Polyoxypropylene polyol D 0.20 mol of cesium hydrogen carbonate and 0.10 mol of rubidium carbonate were added to 1 mol of glycerin, and 1
A vacuum treatment was performed at 05 ° C for 3 hours. 171 g of this compound was charged into an autoclave equipped with a thermometer, a pressure gauge and a stirrer, and after purging with nitrogen, the maximum pressure was 4 kg / c.
Under a condition of m ² (490 kPa) and a reaction temperature of 110 ° C., 7300 g of propylene oxide was charged and the reaction was carried out.
After the charging of propylene oxide was completed, the reaction was continued until no pressure decrease was observed. The time required from the start of charging propylene oxide to the end of the reaction was 850 minutes. The hydroxyl value of this product is 35 mgKOH / g.
Met.

Comparative Example 1 Polyoxypropylene Polyol E 0.25 mol of potassium carbonate based on 1 mol of glycerin
Um was added, and a pressure reduction treatment was performed at 105 ° C. for 3 hours. this
Compound is equipped with thermometer, pressure gauge and stirrer
Charge 141g into an autoclave, replace with nitrogen, and then press at maximum pressure.
Force 4kg / cm ^Two (490 kPa), reaction temperature 110 ° C
Under the conditions of 1,300g of propylene oxide was charged and
Responded. Pressure decrease after completion of propylene oxide charging
The reaction was carried out until a small amount was not observed. Propylene oxide
The time required from the start of the quiside charging to the end of the reaction is 15
It was 20 minutes. The hydroxyl value of this product is 37 m.
It was gKOH / g.

Comparative Example 2 Polyoxypropylene Polyol F 0.25 mol of sodium carbonate was added to 1 mol of glycerin, and a pressure reduction treatment was carried out at 105 ° C. for 3 hours. 129 g of this compound was charged into an autoclave equipped with a thermometer, a pressure gauge and a stirrer, and after purging with nitrogen, the maximum pressure was 4 kg / cm ² (490 kPa) and the reaction temperature was 110.
7850 g of propylene oxide was charged under the condition of ° C to carry out the reaction. After the charging of propylene oxide was completed, the reaction was continued until no pressure decrease was observed. The time required from the start of propylene oxide charging to the end of the reaction is 2
It was 050 minutes. The hydroxyl value of this product is 285 mg
KOH / g. When the autoclave was depressurized and the amount of propylene oxide was measured, a considerable amount of unreacted propylene oxide was present.

Comparative Example 3 Polyoxypropylene Polyol G 0.25 mol of potassium hydroxide was added to 1 mol of glycerin, and depressurized at 105 ° C. for 6 hours. 129 g of this compound was charged into an autoclave equipped with a thermometer, a pressure gauge and a stirrer, and after purging with nitrogen, the maximum pressure was 4 kg / cm ² (490 kPa) and the reaction temperature was 110.
Under the condition of ° C, 7450 g of propylene oxide was charged and the reaction was carried out. After the charging of propylene oxide was completed, the reaction was continued until no pressure decrease was observed. The time required from the start of propylene oxide charging to the end of the reaction was 9
It was 90 minutes. The hydroxyl value of this product is 33 mg KO
H / g.

Comparative Example 4 Polyoxypropylene Polyol H 0.25 mol of cesium hydroxide was added to 1 mol of glycerin. Since cesium hydroxide was used in the form of an aqueous solution having a concentration of 50% by weight, vacuum dehydration treatment was performed at 105 ° C. for 7 hours. 158 g of this compound was charged into an autoclave equipped with a thermometer, a pressure gauge and a stirrer, and after purging with nitrogen, the maximum pressure was 4 kg / cm ² (490 kPa),
Propylene oxide was added under the condition of a reaction temperature of 110 ° C.
The reaction was carried out by charging 350 g. After the charging of propylene oxide was completed, the reaction was continued until no pressure decrease was observed. The time required from the start of charging propylene oxide to the end of the reaction was 985 minutes. The hydroxyl value of this product was 33 mgKOH / g. All of the polyoxyalkylene polyols of Examples 1 to 4 and Comparative Examples 1 to 4 were neutralized by adding water and phosphoric acid after the completion of the reaction and then dried under reduced pressure, and the generated alkali metal phosphate crystals were removed by filtration. Examples and comparative examples are collectively shown in Tables 1 and 2. Catalyst A is cesium carbonate, catalyst B is cesium hydrogen carbonate, catalyst C is rubidium carbonate, catalyst D is potassium carbonate,
Catalyst E is sodium carbonate, catalyst F is potassium hydroxide and catalyst G is cesium hydroxide.

[0024]

[Table 1] <Note> Abbreviation of catalyst A cesium carbonate catalyst B cesium hydrogen carbonate catalyst C rubidium carbonate PO propylene oxide.

[0025]

[Table 2] <Note> Catalyst D Potassium carbonate Catalyst E Sodium carbonate Catalyst F Potassium hydroxide Catalyst G Cesium hydroxide PO Propylene oxide.

[0026]

As described above in detail, in the range investigated by the present inventors, when potassium carbonate and sodium carbonate are used as a polymerization catalyst of propylene oxide, the reaction time of propylene oxide is rubidium carbonate, cesium carbonate, hydrogen carbonate. It was longer than when at least one compound selected from the group consisting of rubidium and cesium hydrogen carbonate was used as a catalyst, and it was difficult to reach a predetermined molecular weight when sodium hydroxide was used.
By using at least one compound selected from the group consisting of rubidium carbonate, cesium carbonate, rubidium hydrogen carbonate and cesium hydrogen carbonate as a catalyst, it is possible to obtain a polyoxygen compound when used at a molar concentration equivalent to that of a conventional alkali metal hydroxide. Excellent alkylene polyol productivity. Further, when used to have a molar concentration equivalent to that of conventional alkali metal carbonates, the productivity of polyoxyalkylene polyol is excellent, and it is possible to produce a high molecular weight polyol used for flexible foam applications and the like. . This is considered to be due to the number of alkali metal elements present in one molecule. Further, rubidium carbonate, cesium carbonate, rubidium hydrogen carbonate and cesium hydrogen carbonate according to the present invention may be used in an aqueous solution, for example, rubidium hydroxide or cesium hydroxide once used for polymerization by the method described in JP-B-52-33000. It can also be obtained by neutralizing alkali hydroxide with carbon dioxide. Therefore, it is possible to produce a polyoxyalkylene polyol by using these catalysts as they are without regenerating these catalysts and using them as alkali hydroxide catalysts. That is, the recovery catalyst can be used, and the production cost of the polyoxyalkylene polyol can be reduced.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Satoshi Tamura Satoshi Tamura 2-1-1, Tango-dori, Minami-ku, Aichi Prefecture Mitsui Toatsu Chemical Co., Ltd. (72) Inventor, Izugawa 2 Tango-dori, Minami-ku, Aichi Prefecture 1-chome Mitsui Toatsu Chemical Co., Ltd.

Claims (1)

[Claims] 1. At least one selected from the group consisting of rubidium carbonate, cesium carbonate, rubidium hydrogen carbonate and cesium hydrogen carbonate as a catalyst when the alkylene oxide is addition-polymerized to an active hydrogen compound having 2 to 8 active hydrogens. A method for producing a polyoxyalkylene polyol, which comprises using a compound.