JP2000169575A - Production of polyoxyalkylene polyol - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a process for producing a polyoxyalkylene polyol with a high degree of conversion. SOLUTION: An epoxide compound is addition polymerized to an active hydrogen compound to produce a polyoxyalkylene polyol by using a reaction vessel which is a vertical reaction vessel 1 having a ratio (D1/H1) of the inner diameter (D1) to the height (H1) of 0.3-0.8 whose bottom is cocentrically and circum-scribably connected to a vertical reaction vessel 2 having a 1-5% volume of the vertical reaction vessel 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a method for producing a polyoxyalkylene polyol. More specifically, the present invention relates to a method for producing a polyoxyalkylene polyol in which an epoxide compound is addition-polymerized to an active hydrogen compound in a reaction vessel having a specific shape.

[0002]

2. Description of the Related Art Generally, a polyoxyalkylene polyol used as a polyurethane raw material or a surfactant is prepared by reacting an active hydrogen compound with an alkali metal compound.
An alkali metal salt of an active hydrogen compound (corresponding to a polymerization initiator) is produced, and then the addition polymerization of the epoxide compound is performed at a temperature of 100 to 150 ° C. and a pressure of 0.4 MPa to 0.6 MPaG (gauge pressure). It is manufactured by doing. Specifically, an active hydrogen compound and an alkali metal compound as a catalyst are charged by a stirring blade attached to a pressure-resistant reactor until a sufficiently stirrable state is obtained, and heating, decompression and dehydration operations, etc., are performed. Produce alkali metal salts of hydrogen compounds. Then, under predetermined polymerization conditions,
An epoxide compound is charged into a reaction vessel until a predetermined molecular weight is reached, and addition polymerization of the epoxide compound is performed as a polymerization initiator. At that time, the volume of the reaction solution increases as the addition polymerization of the epoxide compound proceeds.

Usually, a pressure-resistant reactor with a stirrer is used as a reaction vessel for producing a polyoxyalkylene polyol. Since the bottom of the reactor is dish-shaped, it is usually called a dish-shaped tank (revised stirrer, No. 5).
4, Kazuo Yamamoto, Kagaku Kogyosha, 1984). However, in a dish-shaped tank, when the raw materials are charged until the raw materials can be sufficiently stirred by the stirring blade, the volume of the raw materials (mainly indicating active hydrogen compounds) increases, so that the molecular weight of the obtained polyoxyalkylene polyol is increased. And it is difficult to efficiently produce a high molecular weight polyoxyalkylene polyol.

For example, starting from glycerin having a molecular weight of 92 g / mol as a starting component, the number average molecular weight is 7000 g / mol.
When a degree of polyoxyalkylene polyol is produced in a dish-shaped tank, an addition polymerization of an epoxide compound is performed on a polymerization initiator containing glycerin as a main component, and a molecular weight of 480 is obtained.
After producing a polyol of about g / mol, an addition polymerization of an epoxide compound is then performed on the polyol to produce a polyol having a molecular weight of about 2400 g / mol. Further, addition polymerization of an epoxide compound is performed on a polyol having a molecular weight of about 2400 g / mol, and a molecular weight of 7000 g / mol is obtained.
It is necessary to carry out the reaction up to about mol.

The ratio of the molecular weight that can be produced in a dish-shaped tank (the value obtained by dividing the molecular weight of the polyol after the addition polymerization of the epoxide compound by the molecular weight before the addition polymerization of the epoxide compound (hereinafter referred to as the reaction magnification) is usually Since it is about 4 to 12 times, when producing a high molecular weight polyoxyalkylene polyol, it is necessary to perform a plurality of reactions in a plurality of reactors or one reactor. In order to efficiently produce polyoxyalkylene polyols having different molecular weights, a reactor having a high reaction rate has been desired.

Japanese Patent Application Laid-Open No. 5-247199 discloses a method for producing polyether using a reaction vessel equipped with a max blade having a specific structure (Claim 1). Can be used to obtain a molecular weight of 2
It is described that a wide range of 000 to 50,000 can be produced (paragraph 0022). However, Example 1 describes that 8000 g of propylene oxide was subjected to addition polymerization with respect to 2000 g of polyoxypropylene triol having a molecular weight of 1000 to produce a triol having a molecular weight of 5,000.
Triol 980 having a molecular weight of 5000 prepared in Example 1
It describes that 9020 g of propylene oxide was subjected to addition polymerization with respect to 1 g of the polymer to produce a triol having a molecular weight of 30,000. These reaction magnifications are 5.0 in Example 1 and 6.0 in Example 2, and cannot be said to be a reaction tank capable of efficiently producing a high-molecular-weight one.

[0007]

SUMMARY OF THE INVENTION In view of the above problems, an object of the present invention is to provide a method for producing a polyoxyalkylene polyol having a high reaction rate and capable of efficiently producing a high molecular weight polyoxyalkylene polyol. is there.

[0008]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to solve the above-mentioned problems, and as a result, a small-sized reactor having a specific volume has been connected to the bottom of a vertical reaction vessel having a specific shape. Using a vertical reaction vessel equipped with a stirrer, the addition of an epoxide compound to an active hydrogen compound has been found to be able to efficiently produce a high molecular weight polyoxyalkylene polyol, and the present invention has been completed. .

That is, according to the present invention, there is provided a method for producing a polyoxyalkylene polyol in which an epoxide compound is addition-polymerized to an active hydrogen compound using a reaction vessel equipped with a stirrer, wherein the reaction vessel has a height (H ₁ ). A vertical type having a volume equivalent to 1 to 5% of the reactor 1 at the bottom of the vertical reactor ₁ having a ratio (D ₁ / H ₁ ) of an inner diameter (D ₁ ) to 0.3 to 0.8. A method for producing a polyoxyalkylene polyol is provided, wherein a reaction vessel in which a reaction vessel 2 is concentrically circumscribed and connected is used.

The preferred shape of the vertical reaction vessel 1 used in the present invention is a cylindrical straight body having a dish-shaped bottom at one end and a dish-shaped top at the other end. Further, it is preferable that a plurality of baffles are arranged on the inner wall of the cylindrical straight body of the vertical reaction vessel 1 along the axial direction thereof. A preferred shape of the vertical reaction vessel 2 used in the present invention is one in which a dish-shaped bottom is provided at one end of a cylindrical straight body or an inverted conical straight body, and the other end is a vertical reaction vessel 1. It is circumscribed and connected to the dish-shaped bottom in a body core shape. The ratio (D ₂ / H ₂ ) of the inner diameter (D ₂ ) to the height (H ₂ ) of the vertical reaction vessel 2 is 0.3
-1 is preferred.

The reaction vessel used in the present invention has a high reaction rate, so that a high-molecular-weight polyoxyalkylene polyol can be efficiently produced. Therefore, the polyoxyalkylene polyol obtained by the production method of the present invention is:
In addition to polyurethane foam and a wide range of polyurethane fields such as elastomers, paints, adhesives, flooring materials, waterproofing materials, sealing agents, shoe soles, elastic reinforcing agents, etc., surfactants, hydraulic fluids, lubricants, lubricants, etc. Can be used in a wide range of fields. Further, the bottom projection type reactor according to the present invention can be used for producing a liquid polymer by a batch reaction in addition to producing a polyoxyalkylene polyol.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail. First, one embodiment of the reaction vessel according to the present invention is shown in FIG. 1 and FIG. FIG. 1 is a schematic view showing one embodiment of a reaction vessel according to the present invention. FIG. 2 is a schematic view showing one embodiment of a vertical reaction vessel 2 in which a dish-shaped bottom is provided at one end of an inverted conical straight body. Usually, when the straight body has an inverted conical shape as shown in FIG. 2, the dish-shaped bottom is installed on the side where the cross-sectional area of the straight body is small. Here, the inverted conical shape means a shape whose diameter gradually decreases toward the bottom.

As shown in FIG. 1, a reaction vessel provided with a stirrer according to the present invention comprises a vertical reaction vessel 1 and a small vertical reaction vessel 2 integrated. The vertical reaction vessel 1 is provided with a dish-shaped bottom 4 at one end of a cylindrical straight body 3 and a dish-shaped top 5 at the other end. At the center of the top of the dish-shaped top 5, a nozzle 6 for inserting a stirring shaft of a stirrer is installed,
Manholes 7 are installed at other locations. A plurality of nozzles for connecting pipes, measuring instruments, and the like may be provided on the dish-shaped top 5. It is preferable that a baffle plate 15 is provided on the inner wall of the cylindrical straight body 3 of the vertical reaction vessel 1 along its axial direction. In that case, it is preferable that the baffle plates 15 be installed so as to form a pair at symmetrical positions in the circular cross section of the cylindrical body 3. The number of the baffles 15 should be at least 2
And usually 2 to 6 pieces. For odd numbers,
It is installed at equal intervals along the circumference of the circular cross section of the cylindrical straight body 3.

The small vertical reaction vessel 2 is connected to the center of the dish-shaped bottom 4 of the vertical reaction vessel 1 via one end of the cylindrical straight body 8 or the inverted conical straight body 9. The central portion of the body portion 8 or the inverted conical straight body portion 9 is circumscribed and connected concentrically so that they have the same axis. Cylindrical straight body 8 or inverted conical straight body 9
At the other end, a dish-shaped bottom 10 is installed. Dish bottom 1
A nozzle 11 for inserting a stirring shaft of a stirrer is provided at a central portion of the bottom of the nozzle 0, and a nozzle 12 for discharging a reaction liquid or the like is provided at another portion.

The volume of the vertical reaction vessel 1 to which the present invention can be applied is not particularly limited.
Approximately 000 ml to 20,000 ml are exemplified. An industrial scale is about 1 to 100 m ³ . The ratio of the diameter (D ₁ ) to the height (H ₁ ) of the vertical reaction vessel 1 (hereinafter referred to as D ₁ / H ₁ ) depends on the stirring efficiency,
Affects heating and cooling efficiency. In view of these, D ₁ / H ₁ is preferably 0.3 to 0.8. It is more preferably 0.32 to 0.75, most preferably 0.35 to 0.73. Here, the vertical reaction vessel 1
Is the height (H ₁ ) of the dotted line 13 and the dotted line 1 shown in FIG.
4 and a distance from the bottom of the dish-shaped bottom 4 to the upper end of the cylindrical straight body 3. In the embodiment shown in FIG. 1, D ₁ / H ₁ is 0.39.

The capacity of the small vertical reaction vessel 2 affects the reaction magnification for efficiently producing a high molecular weight polyoxyalkylene polyol. If the volume is too small, it is difficult to install the stirring blade, and it is difficult to perform uniform stirring. On the other hand, if the volume is too large, the effect of increasing the reaction magnification will be reduced. From such a viewpoint, the volume of the vertical reaction vessel 2 is preferably a volume corresponding to 1 to 5% of the volume of the vertical reaction vessel 1. More preferably, the volume is equivalent to 1.5 to 4%, and most preferably, the volume is equivalent to 2 to 3.8%. The ratio of the diameter (D ₂ ) to the height (H ₂ ) of the vertical reaction vessel 2 (hereinafter referred to as D ₂ / H ₂ ) is preferably 0.3 to 1 in consideration of stirring efficiency and the like. Here, the volume of the vertical reaction vessel 1 is indicated by a dotted line 11 from the top mirror surface top of the dish-shaped top 5.
Volume. Vertical reaction vessel 2 in the illustrated embodiment
Is 2.6% of the volume of the vertical reaction vessel 1.
The height of the vertical reaction vessel 2 is a distance from the bottom of the dish-shaped bottom 10 to a dotted line 14. The diameter when the inverted conical straight body is used is the diameter at the dotted line 14 part.

The stirring of the vertical reaction vessel 1 and the vertical reaction vessel 2 may be performed using the same stirrer or different stirrers. Nozzle 6 of vertical reactor 1
Is installed so as to be located at the center point of a circular cross section orthogonal to the axial direction of the cylindrical straight body 3. The nozzle 6 is provided with a mechanical seal or the like. When both reaction vessels are stirred by the same stirrer, the nozzle 6 is passed through the mechanical seal.
A stirring shaft having a length extending from the nozzle to the nozzle 11 of the vertical reaction vessel 2 is provided. The vertical reaction vessel 2
It is preferable to provide a bearing or the like to the nozzle 11 of the dish-shaped bottom 10 to fix the stirring shaft. When the vertical reaction vessel 2 is stirred by a different stirrer, a mechanical seal is provided on the nozzle 11 and a stirring shaft is provided through the mechanical seal.

At least two stirring blades are installed on the stirring shaft. One stirring blade stirs the inside of the vertical reaction vessel 1, and the other stirring blade stirs the inside of the vertical reaction vessel 2. The latter requires one stirring blade, while the former requires at least one stirring blade, depending on the shape of the stirring blade used.

As stirring blades, paddle blades, inclined paddle blades, turbine blades, inclined turbine blades, Faudler blades, bull margin blades, anchor blades (Revised 5th edition Chemical Engineering Handbook, page 891, edited by Chemical Engineering Association, Maruzen Co., Ltd.) Company, issued in 1988), double ribbon wing, double helical wing, max-blend wing, super-blend wing (above, manufactured by Sumitomo Heavy Industries, Ltd.), or full zone wing (manufactured by Shinko Pantech Co., Ltd.), Fine bubbler wing (manufactured by Soken Chemical Co., Ltd.)
And the like. Among these stirring blades, the vertical reaction vessel 2
In the above, a Faudler blade and an anchor blade are preferable.
In the vertical reaction vessel 1, a double helical blade, a max blend blade, a super blend blade, a full zone blade, a fine bubbler blade, an inclined turbine blade, an anchor blade, and the like are preferable.

The diameter (d ₁ ) of the stirring blade of the vertical reaction vessel 1 is
Vertical reaction vessel 1 diameter (D ₁₎ to 0.1 to 0.95 or the diameter of the stirring blade of the vertical reaction vessel 2, the (cylindrical straight body 3) (d ₂₎ are vertical reaction vessel it is preferable 2 to diameter (cylindrical straight body 8) (D ₂₎ is about 0.3 to 0.95. It is preferable that the installation position of the lowermost stirring blade is so close that it does not come into contact with the dish-shaped bottom 3 or 10 of each vertical reaction vessel.

The production method according to the present invention is a method for producing a polyoxyalkylene polyol using the above-mentioned reaction vessel. The raw material is charged through the manhole 7 and the reaction liquid is discharged from the nozzle 11. When the vertical reaction vessel according to the present invention is used for producing a polyoxyalkylene polyol,
Considering the reaction conditions, the design pressure is at least 0.7 MPaG in gauge pressure and the design temperature is at least 150 ° C.
It is preferred that The material is SUS30
4, SUS316 or the like is used.

Next, a method for producing a polyoxyalkylene polyol using the above reaction vessel will be described. A polyoxyalkylene polyol is produced by subjecting an active hydrogen compound to addition polymerization of an epoxide compound in the presence of a catalyst.

As the catalyst, known compounds can be used. For example, sodium, potassium, rubidium, and alkali metal compounds including cesium and the like, strontium, alkaline earth metal compounds including barium and the like,
Alternatively, those in which a crown ether compound is used in combination with these alkaline compounds may be mentioned. Further, Japanese Patent Application Laid-Open
Double metal cyanide complexes described in JP-A-247199, phosphazenium compounds described in JP-A-10-77289, and phosphazene compounds described in JP-A-10-36499 are exemplified. Among these compounds, cesium compounds, phosphazenium compounds, and phosphazene compounds are particularly preferred.

As the active hydrogen compound, alcohols,
Examples include phenol compounds, polyamines, and alkanolamines. For example, monohydric alcohols such as methanol, ethanol, allyl alcohol, octanol and butanol, water, ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, 1,3-propanediol, 1,4-cyclohexanediol, and 1,3 -Dihydric alcohols such as butanediol, 1,4-butanediol, 1,6-hexanediol and 1,4-cyclohexanediol, alkanolamines such as monoethanolamine, diethanolamine and triethanolamine, glycerin, diglycerin , Trimethylolpropane, pentaerythritol,
Dipentaerythritol, tripentaerythritol,
And polyhydric alcohols such as polyglycerol. Also, glucose, sorbitol, dextrose,
Saccharides such as fructose, sucrose, methyl glucoside, hydroxyethyl glucooxide or derivatives thereof, fatty acid amines such as ethylenediamine, di (2-aminoethyl) amine, hexamethylenediamine, and aromatic amines such as toluylenediamine, diphenylmethanediamine And phenol compounds such as bisphenol A, bisphenol F, bisphenol S, novolak, resole, resorcin, hydroquinone, and Mannich compounds. These active hydrogen compounds can be used in combination of two or more. Further, compounds obtained by addition polymerization of these active hydrogen compounds with 6 moles or less of an epoxide compound per 1 equivalent of active hydrogen groups by a conventionally known method can also be used.

The epoxide compound to be addition-polymerized to an active hydrogen compound includes propylene oxide, ethylene oxide, 1,2-butylene oxide, 2,3-butylene oxide, styrene oxide, cyclohexene oxide, epichlorohydrin, epibromohydrin , Methyl glycidyl ether, allyl glycidyl ether, trifluoropropylene oxide and the like. These may be used in combination of two or more. Of these, propylene oxide, 1,2-butylene oxide and ethylene oxide are preferred.

The conditions for the addition polymerization of the epoxide compound are not particularly limited.
The reaction is performed at 60 ° C. and a maximum reaction pressure of 0.8 MPaG (gauge pressure) or less. The polyoxyalkylene polyol produced by the method of the present invention has a molecular weight of 1,000 to 60,000 g / m2, depending on the polyol production catalyst.
ol. According to the present invention, the reaction magnification is 13 to 7
A polyoxyalkylene polyol having a high molecular weight of about 0 times can be efficiently produced.

The polyoxyalkylene polyols produced by the process of the present invention can be used in a wide variety of polyurethane fields such as polyurethane foams and elastomers, paints, adhesives, flooring materials, waterproof materials, sealing agents, shoe soles, elastic reinforcing agents and the like. In addition, it can be used in a wide range of fields such as surfactants, hydraulic fluids, lubricating fluids, and lubricants. The bottom projection type reactor according to the present invention can be used for producing a liquid polymer by a batch reaction in addition to producing a polyoxyalkylene polyol.

[0028]

EXAMPLES Examples of the present invention will be shown below to clarify the bear of the present invention. A phosphazenium compound described in JP-A-10-77289 was used as a catalyst for producing a polyoxyalkylene polyol. The preparation method is as follows.

Preparation Example 1 <Synthesis of phosphazenium compound (hereinafter, referred to as PZN)> 3000 ml of 3 equipped with a thermometer and a dropping funnel
In a one-necked flask, phosphorus pentachloride (manufactured by Junsei Chemical Co., Ltd.) 60.
20 g was weighed and 525 ml of orthodichlorobenzene (manufactured by Mitsui Chemicals, Inc .; hereinafter, referred to as ODCB) was added to form a suspension. This is heated to 30 ° C. and 900 ml of O
In DCB, Angevante Himica International Edition English, Volume 32, 1361
～1363 page 1993, (Reinhard Shubejinga other) synthesized tris (dimethylamino) by the method described phosphazene _{{(Me 2 N) 3 P} = NH} 43
A solution in which 9.27 g was dissolved was added dropwise over 1 hour.
After stirring for 30 minutes at the same temperature,
The temperature was raised to ° C., and the mixture was further stirred for 20 hours. The generated insolubles were filtered, ion-exchanged water was added to the filtrate, and water washing was performed three times.

With respect to 1091.2 g of the water-insoluble layer (hereinafter, referred to as an organic layer) after the water washing treatment, 619.
26 g and 289.5 ml of 1 N hydrochloric acid were added, the aqueous layer was separated, and tetrakis [tris (dimethylamino) phosphoranylideneamino] phosphonium chloride {[(Me ₂
N) ₃ P = N] ₄ P ⁺ Cl ⁻ ｝ was obtained. Further, ion-exchanged water was added to prepare a 2.5% by weight aqueous solution. Then 1
Tetrakis [tris (dimethylamino) phosphoranylideneamino] phosphonium chloride was placed in a polycarbonate cylindrical column filled with ion exchange resin Levatit MP-500 (manufactured by Bayer) whose exchange group was changed to a hydroxyl group with a prescribed sodium hydroxide aqueous solution. 2.5% by weight aqueous solution at 23 ° C., SV (Space Velocity)
At 0.5 (1 / hr), the liquid was passed through the column from the bottom at an ascending flow,
Ion exchange was performed on tetrakis [tris (dimethylamino) phosphoranylideneamino] phosphonium hydroxide.

Further, ion-exchanged water was passed through the column filled with the ion-exchange resin, and the phosphazenium compound remaining in the column was recovered. Then tetrakis
[Tris (dimethylamino) phosphoranylideneamino]
An aqueous solution of phosphonium hydroxide is heated at 80 ° C. under a reduced pressure of 7 ° C.
2 hours under the condition of 980 Pa, further 80 ° C., 133 Pa
Under reduced pressure for 7 hours to obtain powdered tetrakis [tris (dimethylamino) phosphoranylideneamino] phosphonium hydroxide {[(Me ₂ N) _{3
^{P = N] 4 P + OH}} - to give} a (PZN).

The yield determined by weight measurement of the compound after drying was 98%. ¹ H-N with tetramethylsilane in deuterated dimethylformamide solution as internal standard
The chemical shift of MR (400 MHz NMR, manufactured by JEOL) was 2.6 ppm (d, J = 9.9 Hz, 72H). Elemental analysis: C: 38.28, H: 9.82, N:
29.43, P: 19.94 (theoretical value, C: 38.0)
9, H: 9.72, N: 29.61, P: 20.46)
Met.

Reaction vessel A (used in Examples) As a bottom projection type reaction apparatus, as a vertical reaction vessel 1, except for a dish-shaped top, a total internal volume of 2.2 L having the same shape as that shown in FIG. Small autoclave (Nitto Koatsu Co., Ltd.)
SUS-304), and a vertical reaction vessel 2 having the same shape as that described in FIG. 1 and having a volume of 0.06 L was connected to the lower part as shown in FIG. The stirring blades of the vertical reactor 2 are anchor blades, and the stirring blades of the vertical reactor 1 are anchor blades (lower blades) and inclined turbine blades (upper blades). Each stirring blade is connected to one stirring shaft. I attached it. Incidentally, D ₁ / H ₁ in the reaction vessel 1 is 0.39. Hereinafter, it is referred to as a reactor A.

Reactor B (used in Comparative Example) An autoclave (manufactured by Nitto Koatsu Co., Ltd.) having the same shape as the vertical reactor 1 was used except that the vertical reactor 2 in the reactor A was not mounted. Was. Hereinafter, it is referred to as a reactor B.

Molecular weight of polyoxyalkylene polyol The hydroxyl value (unit: mg KOH / g, hereinafter referred to as OHV) measured by the method described in JIS K-1557 is
It was calculated by the equation [56100 × f / OHV]. f is
Shows the number of functional groups of the active hydrogen compound.

Production Example 1 In a glass separable flask equipped with a thermometer, a stirrer, and a nitrogen inlet tube, 7.5 × 10 ⁻² mol of PZN (50 wt. %
Aqueous solution form) at 105 ° C., 1.33 kPa
The heating and dehydration under reduced pressure was performed for 4 hours under the following conditions. Less than,
The compound is called a polymerization initiator. The molecular weight of glycerin is 92.1 g / mol.

Example 1 Under a nitrogen atmosphere, 32.5 g of a polymerization initiator was charged into the reactor A, and the atmosphere was replaced with nitrogen. This is the minimum amount that can be sufficiently stirred in the reactor A. Next, the temperature was raised to 90 ° C., and at the same temperature, the pressure of the reactor was 6.65 kPa.
Was adjusted. Thereafter, while maintaining the temperature at 90 ° C., 2063.5.
g of propylene oxide were charged over 320 minutes. When the pressure in the reactor became constant, 90 ° C., 1.33
Pressure reduction was performed for 30 minutes under the conditions of kPa or less to obtain a crude polyoxyalkylene polyol. 10 parts by weight of ion-exchanged water and 2 parts by weight of an adsorbent (manufactured by Kyowa Chemical Industry Co., Ltd., trade name: KW700P, relative to 100 parts by weight of the crude polyoxyalkylene polyol adjusted to 80 ° C.)
EL) and stirred and mixed at 80 ° C. for 5 hours. Then, while performing the dehydration treatment under reduced pressure,
Decompression treatment was performed for 3 hours at 5 ° C. and 1.33 kPa or less, and 1886.4 g of polyoxyalkylene polyol was recovered by filtration. The OHV of the obtained polyoxyalkylene polyol was 29.3 mgKOH / g, and the molecular weight was 5,744 g / mol. The reaction magnification was 62.4.

COMPARATIVE EXAMPLE 1 Under a nitrogen atmosphere, 292.7 g of a polymerization initiator was charged into the reactor B, and nitrogen replacement was performed. This is the minimum amount that can be sufficiently stirred in the reactor B. Then 90 ° C
And at the same temperature, the pressure in the reactor was 6.65 kP
Adjusted to a. Thereafter, while maintaining at 90 ° C., 180
2.9 g of propylene oxide were charged in 130 minutes. When the pressure of the reactor became constant, 90 ° C.
Under a condition of 1.33 kPa or less, a reduced pressure treatment was performed for 30 minutes to obtain a crude polyoxyalkylene polyol. By the same purification method as in Example 1, 1776.2 g of polyoxyalkylene polyol was recovered. The OHV of the obtained polyoxyalkylene polyol is 278 mgKOH
/ G, and the molecular weight was 605 g / mol. The reaction magnification was 6.6.

<Consideration of the Examples> When the reactor A was used, the minimum chargeable amount of the stirrer was 32.5 g (polymerization initiator) and the allowable charge of propylene oxide was 206.
3.5 g. Therefore, a polyoxyalkylene polyol having a high molecular weight can be obtained, and the reaction magnification is 62.
4 (5744 / 92.1). On the other hand, when the reactor B was used, the minimum chargeable amount for stirring was 292.
7 g (polymerization initiator), and the allowable charge of propylene oxide was 1802.9 g. Therefore, the molecular weight of the obtained polyoxyalkylene polyol is low, and the reaction magnification is 6.
6 (605 / 92.1).

[0040]

According to the present invention, when producing a polyoxyalkylene polyol, the reaction magnification can be significantly improved, and the productivity of the polyoxyalkylene polyol can be greatly improved. Therefore, the polyoxyalkylene polyol obtained by the production method of the present invention is a polyurethane foam, and a wide range of polyurethane fields such as elastomers, paints, adhesives, flooring materials, waterproofing materials, sealing agents, shoe soles, and elastic reinforcing agents. In addition, it can be used in a wide range of fields such as surfactants, hydraulic fluids, lubricating fluids, and lubricants. Further, the bottom projection type reactor according to the present invention, in addition to the production of polyoxyalkylene polyol,
It can be used for the production of liquid polymers by batch reaction.

[0041]

[Brief description of the drawings]

FIG. 1 is a schematic view showing one embodiment of a reaction vessel according to the present invention.

FIG. 2 is a schematic view showing one embodiment of the vertical reaction vessel 2.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Vertical reaction container 2 Vertical reaction container 3 Cylindrical straight body 4 Dish bottom 5 Dish top 6 Nozzle 7 Manhole 8 Cylindrical straight body 9 Inverted conical straight body 10 Dish bottom 11 Nozzle 12 Nozzle 13 Dotted line 14 dotted line 15 baffle

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Saku Izukawa 2-1-1 Tango-dori, Minami-ku, Nagoya-shi, Aichi F-term in Mitsui Chemicals, Inc. 4J005 AA04 AA12 BB01

Claims (5)

[Claims] 1. A method for producing a polyoxyalkylene polyol in which an epoxide compound is addition-polymerized to an active hydrogen compound using a reaction vessel equipped with a stirrer, wherein the reaction vessel has an inner diameter (D ₁ ) with respect to height (H ₁ ). ₁ ) (D ₁
A vertical reaction vessel 2 having a volume equivalent to 1 to 5% of the reaction vessel 1 is concentrically circumscribed on the bottom of the vertical reaction vessel 1 in which / H ₁ ) is 0.3 to 0.8. A method for producing a polyoxyalkylene polyol, comprising using a connected reaction vessel. 2. The method for producing a polyoxyalkylene polyol according to claim 1, wherein the vertical reaction vessel 1 has a cylindrical straight body, a dish-shaped bottom and a dish-shaped top. 3. The method for producing a polyoxyalkylene polyol according to claim 2, wherein the vertical reaction vessel 1 is provided with a baffle plate on the inner wall of the cylindrical straight body along the axial direction. . Is 4. A vertical reaction vessel 2, claim 1, wherein the ratio of the inner diameter (D ₂₎ to the height _{(H 2) (D 2 /} H 2) is characterized in that 0.3 to 1 A method for producing a polyoxyalkylene polyol. 5. A vertical reaction vessel 2 has a dish-shaped bottom at one end of a cylindrical straight body or an inverted conical straight body, and is connected to the dish-shaped bottom of the vertical reaction vessel 1 at the other end. The method for producing a polyoxyalkylene polyol according to claim 1, wherein