JP2002212280A - Method for producing polyether - Google Patents

Abstract

(57) [Problem] To efficiently produce a polyether having a small catalyst content. SOLUTION: A polyether containing a catalyst obtained by ring-opening polymerization of a monoepoxide having 3 or more carbon atoms in the presence of a double metal cyanide complex catalyst is treated with a treating agent containing magnesium oxide to deactivate the catalyst. After that, the deactivated catalyst and treating agent are removed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for producing a polyether, and more particularly, to a method for producing a polyether having a low catalyst content.

[0002]

2. Description of the Related Art Polyethers are used in large quantities in a wide range of applications such as raw materials for synthetic resins, raw materials for surfactants and raw materials for lubricating oils, and are produced on an industrial scale. The polyether can be produced by subjecting a monoepoxide such as an alkylene oxide to ring-opening polymerization with an initiator having at least one or more hydroxyl groups.

[0003] Conventionally, polyether production methods include:
A method of using an alkali catalyst such as an alkali metal hydroxide or an alkali metal alkoxide for the ring-opening polymerization of a monoepoxide has been generally used. However, the method for producing polyether using an alkali catalyst has some problems.

[0004] Specifically, when the molecular weight distribution of the polyether is widened and the monoepoxide is propylene oxide, a monol having an unsaturated group is generated by isomerization of propylene oxide, and the propylene oxide is opened. Cycloaddition leads to the formation of an unsaturated polyether monol having an unsaturated group at one end, and not only a target polyol cannot be obtained, but also a problem that a high molecular weight polyether cannot be practically obtained. Was.

[0005] In particular, when a polyether containing an unsaturated polyether monol at one end is used as a raw material for a resin, that is, a raw material for polyurethane, the presence of this unsaturated group causes the desired reaction to be incomplete, resulting in an unsatisfactory reaction. This is a very serious problem in that it has a bad influence on the physical properties of the obtained polyurethane resin.

As a catalyst for solving these problems, a double metal cyanide complex catalyst is known (US Pat. No. 3,278,387).
457, U.S. Pat. No. 3,278,458, U.S. Pat.
59, U.S. Pat. No. 3,427,256, U.S. Pat.
4, U.S. Pat. No. 3,327,335), which is very useful in that the content of unsaturated polyether monol can be significantly reduced and that a polyether having an extremely high molecular weight can be obtained.

However, it is very difficult to remove the catalyst from a crude polyether obtained by ring-opening polymerization of a monoepoxide having 3 or more carbon atoms using a double metal cyanide complex catalyst. The catalyst cannot be removed by the adsorption treatment.

[0008] The removal of the catalyst is very important in practical use because the residual catalyst in the polyether makes reaction control difficult when used as a raw material for polyurethane and adversely affects the physical properties of the obtained polyurethane resin. Technology.

As a method for removing the catalyst, there is known a method in which the catalyst is deactivated by treating with an alkali metal compound, a specific alkaline earth metal compound or a Lewis acid compound, and then treated with an adsorbent or the like. , The amount of catalyst cannot be reduced to the extent that it can be used practically;
Furthermore, there are many problems that need to be solved for practical use, such as complicated handling of treatment agents.

[0010]

SUMMARY OF THE INVENTION An object of the present invention is to provide a method for producing a polyether capable of efficiently producing a polyether having a very small catalyst content.

[0011]

SUMMARY OF THE INVENTION The present invention provides a method for solving the aforementioned various practical problems by using magnesium oxide as a treating agent for a catalyst.

That is, the present invention provides a polyether containing a catalyst obtained by subjecting a monoepoxide having 3 or more carbon atoms to ring-opening polymerization in the presence of a double metal cyanide complex catalyst with a treating agent containing magnesium oxide. A method for producing a polyether, comprising removing a deactivated catalyst (catalyst decomposed product) and a treating agent after treating to deactivate a catalyst, and the method for deactivating a catalyst in the presence of water. The present invention relates to a method for producing a polyether and a method for deactivating a catalyst in the presence of magnesium hydroxide.

[0013]

DETAILED DESCRIPTION OF THE INVENTION In the present invention, a polyether is produced by ring-opening polymerization of a monoepoxide having 3 or more carbon atoms. Examples of the monoepoxide having 3 or more carbon atoms include propylene oxide, 1,2-butylene oxide, 2,3-butylene oxide, epichlorohydrin, styrene oxide, glycidyl ethers and the like. Monoepoxides can be used alone or in combination of two or more.

The polyether is preferably a polyoxyalkylene polyol, and a compound having at least two or more active hydrogens is used as an initiator for the ring-opening polymerization of a monoepoxide.

The active hydrogen compound is particularly preferably a polyhydroxy compound having two or more hydroxyl groups. Examples of the polyhydroxy compound include dihydric alcohols such as ethylene glycol and propylene glycol;
Examples include trihydric alcohols such as glycerin and trimethylolpropane, and tetrahydric or higher alcohols such as pentaerythryl, dextrose, sorbitol, and sucrose.

An alkylene oxide is added to a compound having a phenolic hydroxyl group or a methylol group such as bisphenol A, a compound having a hydroxyl group and another active hydrogen such as ethanolamine or diethanolamine, a polyhydroxy compound or another active hydrogen compound. A polyhydroxy compound such as a compound obtained by the above method can also be used.

The molecular weight of the initiator is not particularly limited as long as it is lower in molecular weight than the target polyether. However, in commercial production, it is preferably 2 in terms of the reaction rate and the quality of the initiator. Functional or trifunctional polyethers having a number average molecular weight of 200 to 2000 can be used as initiators.

In the present invention, a double metal cyanide complex is used as a catalyst in the ring-opening polymerization of a monoepoxide. The double metal cyanide complex can be represented, for example, by the formula (1). _{M a [M 'x (CN} ) y] b (H 2 O) c · (R) d (1) formula (1), M and M' are metal, R represents an organic ligand,
a, b, x and y are positive integers depending on the valence and coordination number of the metal, and c and d are positive integers depending on the coordination number of the metal.

As the metal M, Zn (II), Fe (I
I), Fe (III), Co (II), Ni (II), Al (II
I), Sr (II), Mn (II), Cr (III), Cu (I
I), Sn (II), Pb (II), Mo (IV), Mo (V
I), W (IV), W (VI), etc.
n (II) is preferably used.

As the metal M ′, Fe (II), Fe (II)
I), Co (II), Co (III), Cr (II), Cr (II
I), Mn (II), Mn (III), Ni (II), V (I
V) and V (V), among which Fe (II),
Fe (III), Co (II) and Co (III) are preferably used.

Examples of the organic ligand R include ketones, ethers, aldehydes, esters, alcohols, amides, nitriles, sulfides and the like, among which ethers, esters, alcohols and amides are preferable.
Specifically, examples of the ether include ethylene glycol dimethyl ether and ethylene glycol diethyl ether, examples of the alcohol include t-butanol, and examples of the amide include N, N-dimethylacetamide.

The double metal cyanide complex is usually used in an amount of from 0.005 to 5.0%, preferably from 0.02 to 2.0%, based on the reaction raw material (total amount of monoepoxide and initiator).
Can be used. If the amount of the double metal cyanide complex is too small, the reaction rate decreases and the reaction step requires a long time, which is not suitable for commercial production. Furthermore, there is a possibility that the quality of the product may be deteriorated due to the high temperature condition for a long time. Conversely, if the amount is too large, not only a large amount of catalyst treating agent is required, but also a long time is required for filtration in the purification step. In addition, the quality of the resulting product may be significantly reduced. Specifically, there is a possibility that a product having a desired molecular weight distribution cannot be obtained, an amount of a by-product increases, a product viscosity increases, and a hue becomes poor.

Monoepoxides are, for example, 80 to 180
C., preferably 90-150.degree. If the polymerization temperature is too low, the reaction rate decreases and the reaction step requires a long time, which is unsuitable for commercial production. Conversely, if the polymerization temperature is too high, the quality of the resulting product may be significantly reduced. Specifically, there is a possibility that a product having a target molecular weight distribution cannot be obtained, an amount of a by-product increases, and a hue becomes poor. Also,
The double metal cyanide complex catalyst may be thermally decomposed and the catalytic activity may be significantly reduced during the reaction.

In the present invention, for example, a polyether having a number average molecular weight of 500 to 20,000 can be obtained as a reaction crude product.

In the present invention, the catalyst contained in the crude reaction product is decomposed and deactivated using a treating agent containing magnesium oxide.

The treating agent is, for example, 0.02 to 100 parts by weight of the reaction crude product in terms of magnesium oxide.
30 parts by weight, preferably 0.1 to 10 parts by weight can be used. If the amount of the treating agent is too small, the decomposition of the catalyst becomes incomplete, not only the filterability is significantly reduced by the remaining catalyst, but also a problem that a transparent product is not obtained.If the amount is too large, the filterability is adversely affected. In addition to the above, there are problems such as a decrease in product yield and an increase in the amount of filter cake.

In the present invention, it is possible to achieve the decomposition of the target catalyst in the absence of water, but it is preferable to treat the crude reaction product in the presence of water. By treating in the presence of water, the decomposition rate of the catalyst is increased, and the decomposition of the catalyst can be achieved in a shorter time. Occurrence can be prevented.

Water is, for example, magnesium oxide 100
20 to 1000 parts by weight, preferably 50
５００500 parts by weight can be present. If the amount of water is too small, the treatment time of the catalyst will be long, or a high treatment temperature will be required. If the added amount of water is too large, a great deal of labor is required to dehydrate the added water, which is unsuitable for commercial production.

In the present invention, the crude reaction product can be treated in the presence of magnesium hydroxide.
For example, it is preferable to add water to magnesium oxide and hydrolyze it, so that magnesium hydroxide coexists with magnesium oxide. The degree of hydrolysis of magnesium oxide is not particularly limited.

Magnesium oxide or magnesium oxide and water are added to the crude reaction product,
The catalyst can be deactivated by stirring at -180 ° C, preferably 80-140 ° C. If the treatment temperature is too low, the decomposition of the catalyst becomes incomplete, not only does the filterability significantly decrease due to the remaining catalyst, but also there is a problem that a transparent product cannot be obtained. It causes increase of impurities, coloring and odor generation due to thermal decomposition of the product. The stirring time can be, for example, 0.5 to 5 hours, preferably 1 to 3 hours. If the stirring time is too short, the decomposition of the catalyst becomes incomplete, and not only does the filterability significantly decrease due to the remaining catalyst, but also there is a problem that a transparent product cannot be obtained. .

By removing the deactivated catalyst, magnesium oxide and coexisting magnesium hydroxide, a polyether having a low catalyst content, for example, a polyether having a catalyst-constituting metal content of 10 ppm or less, preferably 5 ppm or less, can be obtained. Obtainable. M of polyether
The content of g is, for example, 5 ppm or less, preferably 3 ppm or less.
ppm or less.

If the content of the catalyst metal or the Mg content of the polyether is too high, not only does the filterability significantly decrease, but a transparent product cannot be obtained, and the obtained polyale is used as a raw material for urethane resin. However, they have a problem that they adversely affect the urethane-forming reaction and adversely affect the physical properties of the resulting urethane resin.

The deactivated catalyst, magnesium oxide and coexisting magnesium hydroxide can be removed, for example, by using an adsorbent. For example, an adsorbent, preferably an adsorbent and water are added to the catalyst-containing polyether and stirred, so that the deactivated catalyst can be adsorbed to the adsorbent. By using the mixture, the adsorbent and the treating agent that have absorbed the deactivated catalyst can be removed.

As the adsorbent, for example, known ones such as synthetic magnesium silicate, synthetic aluminum silicate and activated clay can be used. The amount of adsorbent used is
For example, 0.1 to 3 parts per 100 parts by weight of the reaction crude product
It can be 0 parts by weight. If the amount of the adsorbent is too small, adsorption of the deactivated catalyst becomes incomplete, and not only does the filterability significantly decrease, but there is a problem that a transparent product cannot be obtained.If the amount is too large, the filterability is adversely affected. In addition, there are problems such as a decrease in product yield, an increase in the amount of filter cake, and contamination of the product by the use of a large amount of adsorbent.

[0035]

EXAMPLES <Production of reaction crude product> According to a known method,
Propylene glycol having a molecular weight of 750 was used as an initiator, and zinc hexacyanocobaltate (III) was used as a catalyst in an amount of 0.15% per reaction crude product (total amount of polypropylene glycol and propylene oxide). Oxide is introduced to a predetermined amount, reacted and aged to obtain a molecular weight of 44.
A reaction crude A of 00 was obtained. The reaction crude product A contained 330 ppm of Zn and 206 ppm of Co, which are the constituent metals of the catalyst.

In addition, in place of polypropylene glycol having a molecular weight of 750, polyoxypropylene glyceryl ether having a molecular weight of 900 using glycerin as a starting material was used as the initiator in the same manner as described above.
A reaction crude B of 00 was obtained. The reaction crude B contained 330 ppm of Zn, which is a metal constituting the catalyst, and 206 ppm of Co.

<Production (Purification) of Polyether> Example 1 20 g of magnesium oxide and 20 g of water as a catalyst treating agent were added to 1000 g of the crude reaction product A at a temperature of 70 ° C., and the temperature was raised to 120 ° C. with stirring. C. for 2 hours. After cooling to 80 ° C., 20 g of synthetic magnesium silicate and 30 g of water were added as adsorbents, and the mixture was stirred at 80 ° C. for 1 hour. The temperature of the reaction crude product was increased by raising the temperature to 105 ° C. while dehydrating under reduced pressure to remove water in the reaction crude product. After filtration, 980 g of a colorless and transparent purified product (polyether) was obtained. Filtration is performed while keeping the temperature of the treatment liquid at 60 ° C., and a Kiriyama type filter as a filter and a Kiriyama filter paper No. as a filter paper. 5B (95 mm diameter) was used.

Example 2 Instead of 20 g of magnesium oxide and 20 g of water, only 40 g of magnesium oxide was used.
970 g of a colorless and transparent purified product (polyether) was obtained in the same manner as in Example 1 except that the treatment time was changed to 4 hours.

Comparative Example 1 The procedure of Example 1 was repeated except that magnesium oxide and water were not added and the treatment time was changed to 4 hours. However, the filterability is very poor, and a cloudy viscous liquid (polyether) 100
It took 10 hours to obtain g.

Comparative Example 2 Water 2 was replaced with 20 g of magnesium oxide and 20 g of water.
Example 1 was repeated except that only 0 g was added. However, the filterability was very poor, and it took 7 hours to obtain 100 g of a cloudy viscous liquid (polyether).

Comparative Example 3 The procedure of Example 1 was repeated, except that calcium oxide was used instead of magnesium oxide. However, the filterability is very poor, and a turbid brown viscous liquid (polyether) 10
It took 8 hours to obtain 0 g.

Comparative Example 4 In place of 20 g of magnesium oxide and 20 g of water, 21 g of a 48% aqueous solution of potassium hydroxide was added. In place of 20 g of synthetic magnesium silicate, synthetic aluminum silicate 3 was used.
970 g of a cloudy viscous liquid (polyether) was obtained in the same manner as in Example 1 except that 0 g was added.

Comparative Example 5 A catalyst was treated by adding 21 g of a 48% aqueous solution of potassium hydroxide in place of 20 g of magnesium oxide and 20 g of water.
Then, at a temperature of 80 ° C., 40 g of sodium acid pyrophosphate
The mixture was heated to 120 ° C. while stirring, treated at 120 ° C. for 1 hour, and then water was removed from the reaction crude product under reduced pressure, and the precipitate was filtered with a filter aid (Showa Chemical Industry Co., Ltd. )
Made by Topco No. 31). Continued
10 g of synthetic magnesium silicate and water 1 as adsorbent
A turbid brown viscous liquid (polyether) 940 was prepared in the same manner as in Example 1 except that 0 g was added and adsorption treatment was performed.
g was obtained.

Comparative Example 6 Example 1 was repeated except that 20 g of aluminum chloride was used as a 30% tetrahydrofuran solution in place of 20 g of magnesium oxide and 30 g of water, and 30 g of synthetic magnesium silicate was added in place of 20 g of synthetic magnesium silicate.
980 g of a turbid brown viscous liquid (polyether) was obtained in the same manner as described above.

Example 3 A reaction crude B was used in place of the reaction crude A,
In the same manner as in Example 1, 970 g of a colorless and transparent purified product (polyether) was obtained.

Comparative Example 7 The procedure of Example 3 was repeated, except that barium oxide was used instead of magnesium oxide. However, the filterability is very poor, and a turbid brown viscous liquid (polyether) 10
It took 10 hours to obtain 0 g.

Comparative Example 8 980 g of a cloudy viscous liquid (polyether) was obtained in the same manner as in Example 3 except that magnesium hydroxide was used instead of magnesium oxide.

<Results> A catalyst component metal in a sample prepared by dissolving a predetermined amount of the purified polyether obtained in each of the Examples and Comparative Examples using a platinum crucible and dissolving the same in dilute hydrochloric acid. (Zn, Co) and metal (M
g, Ca, K, Al, Ba) contents were quantified using an ICP emission spectrometer. The results are shown in Table 1. Table 1 shows the results of visually evaluating the appearance of the obtained polyether and the results of evaluating the filterability. The filterability was evaluated from the filtration rate V (g / cm ² · hr) of the crude reaction product in four steps according to the following indices. ◎ V ≧ 4.7 ○ 4.7> V ≧ 2.4 Δ2.4> V ≧ 1.2 × 1.2> V

[0049]

[Table 1]

[0050]

According to the present invention, the content of the catalyst residue can be greatly reduced as compared with the conventional method, and a transparent polyether having a good hue can be produced.

According to the present invention, the handling of the processing agent and the processing method thereof do not involve complicated operations.

According to the present invention, the adsorption treatment after the catalyst treatment,
In the filtration step, conventional techniques can be applied.

Claims (3)

[Claims] 1. A catalyst obtained by treating a polyether containing a catalyst obtained by ring-opening polymerization of a monoepoxide having 3 or more carbon atoms in the presence of a double metal cyanide complex catalyst with a treating agent containing magnesium oxide. A method for producing a polyether, comprising deactivating the catalyst and removing the deactivated catalyst and treating agent. 2. The method according to claim 1, wherein the catalyst is deactivated in the presence of water. 3. The method for producing a polyether according to claim 2, wherein the catalyst is deactivated in the presence of magnesium hydroxide.