JPH02305819A - Purification of polyether polyol - Google Patents

Abstract

PURPOSE:To obtain a polyether polyol improved in quality, compatibility with another polymer, properties of a molding material, etc., by neutralizing a double bond-terminated polyether polyol by the addition of an aqueous phosphoric acid solution and dehydrating it in a vacuum under specified conditions. CONSTITUTION:A polyether polyol (a) which is an organic compound having at least one active hydrogen atom in the molecule and an MW of 700-7000 is reacted with a double bond-containing monoepoxy compound (b) in the presence of a catalyst which is an alkali metal hydroxide (c) to obtain a double bond-terminated polyether polyol (A). Component A is purified by neutralizing it by the addition of 0.95-1.05mol, per mol of component (c) in A, aqueous phosphoric acid solution (B) comprising 0.95-1.05mol, per mol of component (c) in component A, phosphoric acid (d) and 1.0-3.0wt.%, based on component A, water (e), and dehydrating the neutralized product in a vacuum at 80-150 deg.C at a pressure decreasing rate <=100mmHg/10min.

Description

[Detailed Description of the Invention] [Prior Art] The present invention provides a terminal double bond-containing polyether polyol produced by adding a double bond-containing monoepoxy compound to a polyether polyol using an alkali metal hydroxide as a catalyst. relates to an improved purification process for the removal of alkali metal hydroxides.

Polyether polyols are obtained by addition polymerizing an alkylene oxide to an organic compound having an active hydrogen group in the molecule in the presence of an alkaline catalyst such as caustic potash or caustic soda.

If these alkaline catalysts or their neutralized salts remain in the polyether polyol, they will adversely affect the polyaddition reaction with polyisocyanate and at the same time reduce the physical properties of foamed or non-foamed polyurethane. Normally, when reacting with isocyanate, the concentration of alkaline catalyst or its neutralized salt in polyether polyol is 10 pp.
It is necessary to reduce it to below m.

Purification methods for removing alkaline catalysts or their neutral salts from polyether polyols containing alkaline catalysts include: ■ A method using only an alkaline adsorbent (Japanese Patent Publication No. 38-2
No. 6158, Special Publication No. 33194, Special Publication No. 1973-
123499, etc.), ■Method using ion exchange resin (Special Publication No. 36-2214)
No. 8, JP-A No. 51-23211, etc.); ■ A method of neutralizing with carbon dioxide gas and filtering the resulting carbonate (Japanese Patent Publication No. 52-1982);
．． 33000), but all of these methods require a long time to sufficiently remove the alkali catalyst or its neutral salt, and require the use of large quantities of adsorbents, ion exchange resins, etc. Moreover, the quality of the filtrate deteriorates as the filtration time passes and the filtration pressure increases, so there are many difficulties in putting it into practical use.

Therefore, industrially, the particles of salt produced are relatively large,
For reasons such as ease of handling and filtration, a method of neutralizing with phosphoric acid water, adding an acid or alkali adsorbent before or after dehydration, and filtering after adsorbing excess acid or alkali (for example, Japanese Patent Application Laid-open No. No. 51-101098, Special Publication No. 62-36052
No., Special Publication No. 62-37048, etc.) are frequently implemented.

At this time, the amount of water added is 0.5 to 10% based on the polyether polyol containing an alkaline catalyst, and the amount of phosphoric acid added is the amount of alkaline catalyst in order to reduce the amount of acid or alkali adsorbent used. It is desirable to use the equivalent molar amount, but there is no problem even if it is used in an amount of about 0.5 to 10 times.

After neutralizing the polyether polyol in this way,
By dehydration and filtration, a polyether polyol containing a trace amount of an alkaline catalyst or its neutralized salt can be easily obtained.

[Problem to be solved by the invention]

However, in recent years, a double bond-containing monoepoxy compound is added to the above-mentioned ordinary polyether polyol using an alkali metal hydroxide as a catalyst, and a double bond is introduced at the end of the polymer molecule. Attempts have been made to induce graft polymerization mainly through addition polymerization through double bonds, and to use these graft polymers to improve the compatibility of different polymers, or to improve the strength, impact resistance, and heat resistance of molding materials. ing. (For example, patent application No. 62-31870
However, according to the studies of the present inventors, in order to remove the alkali metal hydroxide used as a catalyst or its neutralized salt from these terminal double bond-containing polyether polyols, However, when we adopted the above neutralization purification method using phosphoric acid water, unlike ordinary polyether polyols, clogging during filtration and leakage of alkali metal hydroxide or its neutralized salt occurred, resulting in a stable product. It has been difficult to obtain products with good physical properties.

[Means to solve the problem]

The present inventors have conducted extensive research in order to improve the drawbacks of the above-mentioned neutralization method, and as a result, have provided the present invention.

That is, in the present invention, a terminal double bond-containing polyether polyol produced by adding a double bond-containing monoepoxy compound to a polyether polyol having a molecular weight of N700 to 7,000 using an alkali metal hydroxide as a catalyst is dissolved in a phosphoric acid aqueous solution. (+) Use 0.95 to 1.05 times the mole of phosphoric acid to the alkali metal hydroxide content in the polyether polyol, (2) 1. 0-3.0
After neutralization by adding weight percent water, (3) at a temperature of 80-150℃, 100mm 11g/1
The present invention relates to a method for purifying a polyether polyol containing terminal double bonds, which comprises dehydrating under reduced pressure at a pressure rate of 0 minutes or less.

Allyl glycidyl ether and glycidyl methacrylate are suitable for the double-bonded gold-containing monoepoxy compound used in the present invention.

The amount of double bond-containing monoepoxy compound used is 0.5 to 5.0 mol per mol of polyether polyol,
Preferably, 1 to 3 mol is appropriate.

If the amount used is less than 0.5 mol, the resulting graft polymer will be insufficient to improve the compatibility of different polymers and the physical properties of the molding material, and if the amount is 5.0 mol or more, graft polymerization will occur rapidly and the graft polymer will Molecular weight control becomes difficult.

The polyether polyol of the present invention having a molecular weight of 700 to 7,000 is suitably an organic compound having at least one active hydrogen group in the molecule, such as monohydric alcohols such as methanol, ethanol, butanol, ethylene glycol, etc. , dihydric alcohols such as propylene glycol and dipropylene glycol, polyhydric alcohols such as glycerin, pentaerythritol, sorbitol, and sucrose, and amine compounds such as ethylenediamine, triethanolamine, and diethylenetriamine, and alkylene oxides such as ethylene oxide. Examples include compounds obtained by addition polymerization of propylene oxide, butylene oxide, and the like.

In addition, as the alkali metal hydroxide used when adding the double bond-containing monoepoxy compound to this polyether polyol, sodium hydroxide, potassium hydroxide, etc. are suitable, and the amount used is particularly limited. Although it is not done,
It is usually used in an amount of 0.1 to 1.0% by weight based on the polyether polyol.

If the amount is less than 0.1 t%, the alkylene oxide addition rate will decrease significantly, and if it is 1.0 wt% or more, the alkylene oxide addition rate will reach a plateau, and at the same time the phosphoric acid used for neutralization purification and the adsorbent will decrease. It is economically unfavorable because the amount used increases.

The amount of phosphoric acid used during neutralization and purification is 0.9% relative to the alkali metal hydroxide contained in the polyether polyol.
A suitable amount is 5 to 1.05 moles.

If it is less than 0.95 mole times, the neutralization reaction will be insufficient, and even if an alkali adsorbent is used after neutralization and purification, a considerable amount of unreacted alkali metal hydroxide will be mixed into the product, which will adversely affect the physical properties. effect.

If the amount exceeds 1.05 moles, it becomes extremely difficult to filter the phosphate after neutralization and dehydration, and phosphate crystals leak into the product, resulting in a cloudy product.

Add water during neutralization! ! k (phosphoric acid-entrained water + added water) is 1.0 to 3.0% by weight based on the polyether polyol.

If it is less than 1.0% by weight, the neutralization reaction will not proceed smoothly and a considerable amount of unreacted alkali metal hydroxide will be mixed into the product.
．． If it is more than 0% by weight, phosphate crystals will leak into the product, making the product cloudy and having an adverse effect on the physical properties.

The dehydration conditions after neutralization are a temperature of 80 to 150'', a C1 pressure reduction rate of 10On++mlG, and 710 minutes or less.

If the temperature is below 80°C, sufficient dehydration will not be possible.
Moreover, if it is higher than +50'C, it is not preferable because the product will be colored and odor will be generated.

Furthermore, if the pressure reduction rate is faster than 100 mm 1 lG/10 minutes, phosphate crystals will leak into the product and at the same time the filterability of phosphate will deteriorate.

The acid or alkali adsorbent used during neutralization and purification may be added at any step, such as during phosphoric acid neutralization, vacuum dehydration, or filtration, but it is recommended to It is preferable to add the liquid, followed by dehydration under reduced pressure and filtration.

In addition, examples of this acid or alkali adsorbent include Kyoward 100.200.300.500.600.7
00 (manufactured by Kyowa Chemical Industry), Tomix AD-200,3
Commercially available adsorbents such as 00,500,600,700 (manufactured by Tomita Pharmaceutical Industries) were used at 0.0% for polyether polyol.
1 to 0.1% by weight is used.

The polyether polyol obtained from Keyaki, which has a double bond at the end, induces graft polymerization through addition polymerization through the double bond, and these graft polymers can be used to improve the compatibility of different polymers. Or, it has excellent properties such as promoting the improvement of physical properties of molding materials. In addition, by applying the phosphoric acid neutralization method of the present invention, products with stable quality can be easily and efficiently produced, so that the method has high industrial utility value.

〔Example〕

EXAMPLES Hereinafter, in order to explain the present invention more specifically, Examples and Comparative Examples will be given and explained, but the present invention is not limited to these Examples.

Example 1 OHH value 337 (molecular ff
i5000) polyether polyol 1500g
(0.3 mol), allyl glycidyl ether 41.0
g (0.36 mol), and potassium hydroxide 7.5 g (
0.13 mol) was charged into a 32 autoclave at once and reacted at 120''C for 6 hours after purging with nitrogen.

After the reaction was completed, it was confirmed by gas chromatography that unreacted allyl glycidyl ether in the reaction solution was traced, the internal temperature was lowered to 90°C, and 15.0 g of 85% phosphoric acid was added.
(0.13 mol) and 27.8 g of water to give 30
Stir for 1 minute (↑).The amount of water added at this time (water added with phosphoric acid and water molecules) was 6.5%, which corresponds to 2.0% of the polyether polyol.7.
After adding 5 g and further stirring for 30 minutes, dehydration was gradually performed using a vacuum pump at a pressure reduction rate of 50 mm 1 G/10 minutes. After reaching an absolute pressure of 30+nm 11G, dehydration and drying was continued at 90°C for 3 hours.

After the dehydration is completed, put the A4
Place a filter paper and add 1 part of Radiolight 900 as a filter aid.
0.0 g was precoated, the reaction solution was charged, and the nitrogen pressure was set to 2.
．． Pressure filtration was performed at 0 kg/dG.

It took 5 minutes to complete the filtration, and the obtained product was yellow and transparent, and elemental analysis showed that the K content was 4 ppw1, the P content was 5 ppm,
Moreover, the water content was 0.015%.

Examples 2 to 9, Comparative Examples 1 to 16 Example 1 except that the amount of water added and the amount of 85% phosphoric acid added were changed.
Neutralization and purification was performed using the same method as above.

The neutralization conditions and results are shown in Table-1.

Examples 10 to 18, Comparative Examples 17 to 32 O H value obtained by adding propylene oxide and ethylene oxide to propylene glycol 56.1
(molecule 12000) polyether polyol 1500
g (0.75 mol), allyl glycidyl ether 16
Using 0.0 g (1.4 mol), neutralization and purification were performed in the same manner as in Examples 1 to 16.

Table 2 shows the neutralization conditions and results.

Example! 9-27, Comparative Examples 33-48 Glycidyl meccrylate 85.2g (0.6 mol)
Neutralization and purification was performed in the same manner as in Examples 1 to 16 except that .

Table 3 shows the neutralization conditions and results.

Examples 28 to 28, Comparative Examples 49 to 51 Example - except for changing the pressure reduction rate and temperature during vacuum dehydration
Medium Fa purification was performed in the same manner as in 1.

The dehydration conditions and results are shown in Table 4.

Examples 30-31. Comparative Examples 52 to 54 Example except for changing the pressure lowering rate and temperature during vacuum dehydration
Neutralization and purification was performed in the same manner as for 1O.

The dehydration conditions and results are shown in Table-5.

Examples 32 to 33, Comparative Examples 55 to 58 Example - except for changing the pressure lowering rate and temperature during vacuum dehydration
Neutralize using the same method as 27? # Made.

The dehydration conditions and results are shown in Table-6.

Reference Example 5 parts of di-tert-butyl peroxide was added as a radical initiator to 1000 parts of the polyether polyol having an allyl group at the end obtained in Example 1.
The reaction was carried out at 50°C for 6 hours.

After the reaction was completed, decompression treatment was carried out at 150° C. and 20 smHG for 1 hour to remove decomposition products of the radical initiator.

Viscosity 15.000CP/25℃, molecule 1i30.000
~70,000 distribution. (Polystyrene equivalent)
A high molecular weight polyether polyol was obtained.

Tobi 11 Yode (U 2-stop thermometer, 08 value 56.1 obtained by addition polymerization of propylene oxide to glycerin in a pressure-resistant container equipped with a stirrer)
(molecular weight 3000) polyether polyol (A)
The flask was filled with 200 parts and replaced with 11 nitrogen gas several times.

Raise the internal temperature to 100℃ while stirring for 1'A, and after reaching the temperature,
A mixture of 50 parts of high molecular weight polyether polyol, 279 parts of styrene, 120 parts of acrylonitrile, and 8 parts of azobisisobutyronitrile was continuously charged using a pump over a period of 4 hours.

After further stirring at the same temperature for 30 minutes, vacuum treatment was performed at 2t) mdg for 3 hours to obtain 33.8mgKOl of 08 value.
l/g, viscosity 4, 900CP/25℃, K min 0.3
A white emulsion-like polymer polyol with good dispersion stability and a P content of 0.4 ppm was obtained.

For comparison, a similar test was conducted without the addition of the above-mentioned high molecular weight polyether polyol, and the stirrer stopped due to overload immediately after the continuous charging of raw materials was completed. When the pressure container was opened, a large amount of solid matter was found adhering to the stirring blades and the ceiling of the container.

〔Effect of the invention〕

The method of the present invention can be produced more efficiently (shorter filtration time) than conventional methods, and the polyether polyol obtained by the present invention has less coloring (,
It is clear from Tables 1 to 6 and the reference examples that products with stable quality and low K and P content can be easily obtained.

Claims (1)

[Claims] 1. A terminal double bond-containing polyether polyol produced by adding a double bond-containing monoepoxy compound to a polyether polyol having a molecular weight of 700 to 7,000 using an alkali metal hydroxide as a catalyst. When neutralizing and purifying with a phosphoric acid aqueous solution, (1) using phosphoric acid in an amount of 0.95 to 1.05 times the mole of alkali metal hydroxide in the polyether polyol, (2) polyether polyol 1.0-3.0 for
After neutralization by adding weight percent water, (3) 100mmHg/10 at a temperature of 80-150℃.
1. A method for purifying a polyether polyol containing terminal double bonds, the method comprising dehydrating under reduced pressure at a pressure reduction rate of less than 1 minute. 2. The method for purifying a polyether polyol containing terminal double bonds according to claim 1, wherein the double bond-containing monoepoxy compound is allyl glycidyl ether or glycidyl methacrylate. 3. Purification of polyether polyol containing terminal double bonds according to claim 1, wherein the amount of the double bond-containing monoepoxy compound used is 0.5 to 5.0 mol per 1 mol of polyether polyol. Method.