JPH04214722A - Production of polyethers - Google Patents

Abstract

PURPOSE:To obtain terminal oxyethylated polyethers with a low impurity content such as a decomposed catalyst by synthesizing polyethers using a multiple metallic cyanide complex catalyst and reacting with terminals of the resultant polyethers with ethylene oxide. CONSTITUTION:An alkali metal or its compound is added to polyethers synthesized by using a multiple metallic cyanide complex catalyst and containing the catalyst to deactivate the catalyst. Adsorption treatment is then carried out in the presence of water and the resultant polyethers are filtered and subsequently dehydrated to afford the purified polyethers or ethylene oxide is further reacted therewith after deactivating the catalyst. The adsorption treatment is then performed in the presence of water and the obtained polyethers are filtered and then dehydrated to provide the purified terminal oxyethylated polyesters.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing polyethers, and more particularly to a method for producing polyether polyols.

0002

[Prior Art] Polyethers obtained by ring-opening reaction of monoepoxides such as alkylene oxides with initiators are widely used as raw materials for synthetic resins such as polyurethane, surfactants, lubricants, and other uses. . The initiator is a hydroxyl group-containing compound represented by A-(H)n, (A: a residue obtained by removing the hydrogen atom of the hydroxyl group of the hydroxyl group-containing compound, n: an integer of 1 or more). Examples of initiators include monohydric alcohols, polyhydric alcohols,
There are monohydric phenols and polyhydric phenols. Compounds having a hydroxyalkylamino group (alkanolamines, amines-alkylene oxide adducts, etc.) are also used as initiators. Furthermore, polyethers obtained by reacting the above-mentioned initiators with monoepoxides can also be used as initiators.

Polyethers are the following compounds obtained by subjecting the above-mentioned initiator to a ring-opening addition reaction of a large number of monoepoxides. A-[-(-R-O-)m -H]n where (-R-O-) represents a ring-opening unit of monoepoxide, and m represents an integer.

Conventionally, as a method for producing polyethers, a method in which monoepoxide is reacted in the presence of an alkali catalyst has been widely used. Alkali metal compounds such as potassium hydroxide and sodium hydroxide have been used as alkali catalysts. However, polyethers obtained using an alkali catalyst have the following problems. In other words, an unsaturated monool produced by isomerization of a monoepoxide, especially propylene oxide, serves as an initiator, and an unsaturated polyether monool (hereinafter also referred to as an unsaturated monool) is produced by ring-opening addition of a monoepoxide to this. do.

[0005] As the molecular weight of polyethers increases, the rate of isomerization increases, and this tendency becomes noticeable when the molecular weight is 6,500 or higher (in the case of trifunctional polyethers). Therefore, when propylene oxide is used as the monoepoxide,
Synthesis of the above polyethers was virtually impossible.

[0006]

On the other hand, it is known to produce polyethers using a multimetal cyanide complex as a catalyst (see, for example, the following US patent specifications, US 3278457, US 3278458, U.S.
3278459, US 3427256, US 34
27334, US 3427335). This catalyst produces less of the above-mentioned unsaturated monools and is also capable of producing extremely high molecular weight polyethers.

However, the above multimetal cyanide complex catalyst has the following two problems. First, it was difficult to remove the catalyst from polyethers obtained by ring-opening reaction of a monoepocide having 3 or more carbon atoms as an initiator using a multimetal cyanide complex as a catalyst. It is not possible to separate the catalyst by filtration or by adsorption with an adsorbent such as activated carbon.

Therefore, in order to remove this catalyst from polyethers using metal cyanide complexes, it is necessary not only to simply filter it or treat it with an adsorbent, but also to decompose the catalyst with an alkali or acid. It is necessary to ionize and then remove these decomposed products, residual alkalis, and residual acids by adsorption and filtration.

Secondly, it has been difficult to react ethylene oxide to hydroxyl groups using a multimetal cyanide complex as a catalyst. Using a multimetal cyanide complex as a catalyst,
When ethylene oxide is subsequently fed to polyethers obtained by ring-opening reaction of monoepoxides having 3 or more carbon atoms to an initiator, polyethylene glycol, which is a homopolymer of ethylene oxide, is produced, and the terminal hydroxyl groups of polyethers are Uniform addition of ethylene oxide does not occur.

[0010] A method is known in which a multimetal cyanide complex catalyst is treated with an alkali to deactivate the catalyst and remove the catalyst residue, and a method in which ethylene oxide is added after the alkali treatment and then the catalyst residue is removed. As a method of treatment with an alkali, a method using an alkali metal, an alkali metal hydroxide (US 4,355,188), or an alkali metal hydride (US 4,721,818) is known. It is also known to perform treatment with an adsorbent after these treatments. However, this method requires a large amount of adsorbent to sufficiently remove the decomposition products and alkaline components of the multimetal cyanide complex, and it is necessary to develop a technology that can remove them more completely with a smaller amount of adsorbent. It was wanted.

[0011]

[Means for Solving the Problems] The present invention provides the following invention which has been made to solve the above-mentioned problems.

In the presence of a multimetal cyanide complex catalyst, the initiator having at least one hydroxyl group has 3 carbon atoms.
Polyethers containing the catalyst obtained by ring-opening addition reaction of the monoepoxide described above are treated with a treatment agent made of an alkali metal or its compound to deactivate the catalyst, and then water and an adsorbent are added. A method for producing polyethers, which comprises performing adsorption treatment in the presence of water, followed by filtration to remove the adsorbent, and then dehydration treatment.

In the presence of a multimetal cyanide complex catalyst, the initiator having at least one hydroxyl group has 3 carbon atoms.
Polyethers containing the catalyst obtained by ring-opening addition reaction of the monoepoxides described above are treated with a treatment agent made of an alkali metal or its compound to deactivate the catalyst, and then the polyether is A method for producing polyethers, which comprises reacting ethylene oxide with ether, then adding water and an adsorbent, performing an adsorption treatment in the presence of water, filtering to remove the adsorbent, and then dehydrating.

[0014] The double metal cyanide complex in the present invention is
As shown in the above-mentioned known examples, it is thought to have the structure of the following general formula (1). M1a[M2x(CN)y]b(H2O)c(R)d
... (1) However, M1 is Zn(II), Fe
(II), Fe(III), Co(II), Ni(II)
), Al(III), Sr(II), Mn(II), C
r(III), Cu(II), Sn(II), Pb(I
I), Mo(IV), Mo(VI), W(IV), W(
VI), and M2 is Fe(II), Fe(II
I), Co(II), Co(III), Cr(II),
Cr(III), Mn(II), Mn(III), Ni
(II), V (IV), V (V), etc., where R is an organic ligand, and a, b, x and y are positive integers that vary depending on the valence and coordination number of the metal. , c and d are positive numbers that vary depending on the coordination number of the metal.

M1 in general formula (1) is Zn(II
) is preferable, and M2 is Fe(II), Fe(III),
Co(II), Co(III), etc. are preferred. Examples of organic ligands include ketones, ethers, aldehydes, esters, alcohols, amides, and the like.

As mentioned above, the double metal cyanide complex represented by the general formula (1) is composed of the metal salt M1Xa (M1,
a is the same as above, X is an anion that forms a salt with M1) and polycyanometalate (salt) Ze[M2x(C
N)y]f(M2, x, y are the same as above. Z is hydrogen,
Alkali metals, alkaline earth metals, etc., e, f are Z,
A positive integer determined by the valence and coordination number of M2) or a solution of a mixed solvent of water and an organic solvent are mixed together, and the resulting double metal cyanide is brought into contact with the organic ligand R. , is produced by removing excess solvent and organic compound R.

Polycyanometalate (salt) Ze [M2
x(CN)y]f, various metals including hydrogen and alkali metals can be used for Z, but lithium salts, sodium salts, potassium salts, magnesium salts, and calcium salts are preferable. Particularly preferably ordinary alkali metal salts,
namely sodium salt and potassium salt.

Polyethers are usually produced by reacting a mixture of a monoepoxide and an initiator in the presence of a catalyst. Alternatively, the reaction can be carried out while gradually adding monoepoxide to the reaction system. Although the reaction occurs at room temperature, the reaction system can be heated or cooled if necessary. The amount of the catalyst used is not particularly limited, but it is appropriate to be about 1 to 5000 ppm, and 30 to 100 ppm, based on the initiator used.
0 ppm is more preferable. Introducing the catalyst into the reaction system is
It may be introduced all at once at the beginning, or it may be introduced in parts sequentially.

By using this double metal cyanide catalyst, it is possible to synthesize polyethers with a low content of unsaturated monols, or with a low content of unsaturated monols and an extremely high molecular weight. .

As the alkali metal or its compound in the present invention, in addition to strong alkalis such as the above-mentioned known simple alkali metals, alkali metal hydrides, and alkali metal hydroxides, alkali metal alcoholates can be used. As the alkali metal of these alkali metals and their compounds, sodium or potassium is preferable. As the alcoholate, alcoholates of monohydric or polyhydric alcohols are suitable. As the alcohol, an alcohol with a low boiling point is preferable. This is because, after reacting polyethers with alcoholates, it is extremely easy to remove the alcohol produced as a by-product. Therefore, as the alcohol, lower monools, particularly methanol or ethanol are preferred. Methylates and ethylates of these metals are easy to handle and process, and are easy to use industrially as processing agents.

[0021] The alcoholate of sodium or potassium used here is diluted as an alcohol solution;
Alternatively, a single powder can be used. As a method for treating polyethers containing a multimetal cyanide complex, an alkali metal or a compound thereof (hereinafter referred to as alkali metal, etc.) is added, preferably at 80 to 180 °C,
Particularly preferred is a method in which the material is heated to 100 to 150°C, subjected to reduced pressure treatment if necessary, and then purified.

When reacting ethylene oxide,
A preferred method is to add an alkali metal or the like, heat in the same manner, and then perform a vacuum treatment to remove by-product alcohol, then react with ethylene oxide, and then purify.

[0023] In the purification process, water and an adsorbent are first added in the first stage, and adsorption treatment is carried out in the presence of water. The adsorption treatment is usually performed by stirring at a predetermined temperature for a predetermined time. The adsorption treatment temperature used is about 40° C. to the boiling point of water, and the treatment time depends on the amount to be treated, but is suitably 30 minutes or more.

As the adsorbent, metal oxides such as synthetic magnesium silicate, aluminosilicate, silica, and zeolite are preferred, and synthetic magnesium silicate is particularly preferred. The amount of water is 0.1 per polyether.
-20% by weight is suitable, especially 0.5 - 10% by weight
is preferred. If the amount of water is too small, the alkali metal bonded to the polyether (presumably in the form of an alkoxide) will not be sufficiently removed, and purification will likely be insufficient. In addition, if the amount of water is too large, the dehydration process described later requires a lot of time and energy, which tends to reduce economic efficiency.

[0025] The amount of adsorbent varies depending on the amount of the catalyst, its decomposition products, or alkali present.
Usually, 0.5 to 20% by weight based on the polyether is suitable, and 1 to 10% by weight is particularly preferable. Adsorption treatment in the presence of water has the effect of increasing the adsorption of the catalyst, its decomposition products, or alkali, and also improving the filtration performance in the next step. That is, the filtration rate is high and the filtration yield is also increased.

After the adsorption treatment, filtration is performed to remove the adsorbent from the polyether, followed by dehydration to remove water. If dehydration is performed first as described above, filtration efficiency will decrease. Filtration can be carried out using filters having a variety of filters. Dehydration is usually carried out by heating under reduced pressure.

In the present invention, the alkaline component may be neutralized and the neutralized salt produced thereby may be removed before the adsorption treatment. For neutralization and removal of neutralized salts, methods conventionally used in purification after producing polyethers using an alkali catalyst can be employed. Neutralization is performed using an acid or an aqueous acid solution, and the purified neutralized salt can be removed by filtration. The adsorption filtration removes impurities such as fine salts, dissolved salts, and metal ions that could not be removed. The water used at this time may be removed once, or may be used as it is as water in the next adsorption treatment. Examples of acids include inorganic acids, such as hydrochloric acid, sulfuric acid, sulfurous acid, phosphoric acid, nitric acid, and/or their acid salts; examples of organic acids include carboxylic acids, polycarboxylic acids,
Sulfonic acid etc. are used. The amount of acid used is 1.0 to 3.0, preferably 1.0 to 2, relative to the alkali metal.
．． 0 equivalent is suitable.

The polyethers obtained by the method of the present invention are preferably polyoxyalkylene polyols. A polyoxyalkylene polyol is obtained by subjecting an initiator having at least two hydroxyl groups to a monoepoxide such as an alkylene oxide through a sequential ring-opening addition reaction.

As the initiator, polyhydroxy compounds having 2 to 8 hydroxyl groups are particularly preferred. Examples of polyhydroxy compounds include dihydric alcohols such as ethylene glycol and propylene glycol, trihydric alcohols such as glycerin, trimethylolpropane, and hexanetriol, and tetrahydric or higher alcohols such as pentaerythritol, diglycerin, dextrose, sorbitol, and sucrose. There are polyethers that have a lower molecular weight than alcohols and the target products obtained by reacting these alcohols with monoepoxides such as alkylene oxides.

[0030] In addition, compounds having a phenolic hydroxyl group or methylol group such as bisphenol A, resol, and novolac, compounds having a hydroxyl group and other active hydrogen such as ethanolamine and diethanolamine, and monoepoxides such as alkylene oxides are reacted with these compounds. There are polyethers that have a lower molecular weight than the target product obtained by

Furthermore, there are polyethers having a lower molecular weight than the target product obtained by reacting a monoamine or polyamine having at least two hydrogen atoms bonded to a nitrogen atom with a monoepoxide such as alkylene oxide. In addition, phosphoric acid, its derivatives, and other polyhydroxy compounds can also be used. Two or more types of these polyhydroxy compounds can also be used in combination.

The present invention can also be applied to a method for producing a polyether monool by subjecting a monovalent initiator to a ring-opening reaction of a monoepoxide. Examples of monovalent initiators include methanol, ethanol, butanol, hexanol, other monools, phenol, phenol derivatives such as alkyl-substituted phenols, and target products obtained by reacting these with monoepoxides such as alkylene oxides. There are also low molecular weight polyethers. Furthermore, there are polyethers having a lower molecular weight than the target product obtained by reacting a monoamine or polyamine having one hydrogen atom bonded to a nitrogen atom with a monoepoxide such as alkylene oxide.

The monoepoxide used in the present invention is a monoepoxide having 3 or more carbon atoms, and alkylene oxide having 3 or more carbon atoms is particularly preferred. More preferred are alkylene oxides having 3 to 4 carbon atoms, such as propylene oxide, 1,2-butylene oxide, 2,3-butylene oxide, and epichlorohydrin, and most preferred is propylene oxide. They can be used alone, two or more of them, or in combination with other monoepoxides such as styrene oxide, glycidyl ether, and glycidyl ester. In the case of using two or more alkylene oxides or alkylene oxide and other monoepoxides, they can be added as a mixture or added sequentially to form a random polymer chain or a block polymer chain.

However, even if it is attempted to directly react ethylene oxide with an initiator or polyether using a composite metal cyanide as a catalyst, polyethylene glycol, which is a homopolymer of ethylene oxide, is produced. For this reason, for example, this catalyst can be used to copolymerize ethylene oxide with other monoepoxides, or polyethers obtained using composite metal cyanide as a catalyst can be subsequently reacted with ethylene oxide to form primary hydroxyl groups. It is difficult to obtain high proportions of polyethers. However, a hydroxy compound having an oxyethylene group, such as a polyoxyalkylene polyol having an oxyethylene group, can be used as an initiator.

According to the method of the present invention, the hydroxyl groups of polyethers are converted into alcoholates by treatment with an alkali metal, etc., and then oxyethylene groups are introduced into the molecular terminals by reacting with ethylene oxide, and the catalyst components are further separated. This makes it possible to obtain polyethers with a high proportion of primary hydroxyl groups.

The molecular weight of the polyethers obtained is not particularly limited. However, products that are liquid at room temperature are preferred from the viewpoint of their use. The reaction amount of monoepoxide per mole of initiator is preferably at least about 10 moles, more preferably at least about 50 moles. More preferably, polyethers are obtained by reacting an average of at least about 10 molecules, especially at least about 30 molecules per hydroxyl group of the initiator. Moreover, when expressed in terms of hydroxyl value, a value of 200 or less, particularly 100 or less is suitable. For example, as a raw material for polyurethane, a liquid polyether polyol having a hydroxyl value of about 5 to 200, particularly 5 to 60 is preferred. For other uses, such as raw materials for oil such as hydraulic oil, polyether poly(or mono)ols within the above range are preferred.

The polyether polyol obtained by the present invention is most useful as a polyol for polyurethane raw materials, used alone or in combination with other polyols. Furthermore, the polyether poly(or mono)ol obtained by the present invention can also be used as a raw material or additive for synthetic resins other than polyurethane. Furthermore, it can be used as a lubricating oil, an insulating oil, a hydraulic oil, and other oils, or as a raw material thereof. Furthermore, the polyethers obtained according to the present invention can be converted into other compounds such as alkyl ether compounds and acylated compounds and used for various purposes.

[0038] The present invention will be specifically explained below with reference to Examples and Comparative Examples, but the present invention is not limited only to these Examples.

[0039]

[Example] The following polyoxypropylene polyol used in the examples etc. was prepared by using a polyoxypropylene polyol with a molecular weight of about 500 as an initiator, adding a zinc hexacyanocobaltate complex catalyst to it, and supplying propylene oxide. This is a polyoxypropylene polyol obtained by reacting at 120°C until it reaches a predetermined molecular weight. This polyoxypropylene polyol produced contained the following amount of metal component as a catalyst.

Polyol A: Contains zinc hexacyanocobaltate complex catalyst (Zn 40ppm, Co2
1 ppm), polyoxypropylene diol polyol B with a molecular weight of 4000; containing a zinc hexacyano iron complex catalyst (Zn 60 ppm, Fe 32 ppm),
Polyoxypropylene triol polyol C with a molecular weight of 6000; containing a zinc hexacyanocobaltate complex catalyst (Zn 80ppm, Co 38ppm)
, polyoxypropylene triol with a molecular weight of 10,000

[Example 1] Potassium methylate (30%
22.2 g of methanol solution) was added, and the methanol removal reaction was carried out at 90° C. and 20 Torr for 2 hours. Next, add 30 g of water and 50 g of synthetic magnesium silicate, and heat to 90°C.
The mixture was stirred at normal pressure for 2 hours for adsorption treatment, and then filtered using filter paper. After filtration, 120℃, 20Torr
Dehydration was performed under reduced pressure for 2 hours to obtain a purified polyol. Its properties and filtration rate are shown in Table 1.

[Comparative Example 1] A demethanol reaction was carried out using potassium methylate to 1000 g of polyol A under the same conditions as in Example 1. Then, 50 g of synthetic magnesium silicate was added, and the mixture was heated at 90°C.
The mixture was stirred at normal pressure for 2 hours for adsorption treatment, and then filtered using filter paper. The filter paper became clogged during filtration, and only 40% by weight of the total polyol could be filtered. Table 1 shows the properties and filtration rate of the obtained polyol.

[0043]

[Table 1]

[Example 2] Sodium methylate (95 g) was added to 1000 g of polyol B.
% powder) was added and the demethanol reaction was carried out at 90%.
After conducting the reaction at 15 Torr for 1.5 hours, 200 g of ethylene oxide was introduced and the reaction was carried out at 90°C for 2 hours. Next, 12 g of water and 36 g of synthetic magnesium silicate were added, and the mixture was stirred at 90° C. and normal pressure for 2 hours for adsorption treatment, and then filtered using filter paper. After filtration, 12
Dehydration was performed under reduced pressure at 0° C. and 20 Torr for 2 hours to obtain a purified polyol. Its properties and filtration rate are shown in Table 2.

[Comparative Example 2] Using 1000 g of polyol B, ethylene oxide was reacted in the same manner as in Example 2. Next, 36 g of synthetic magnesium silicate was added, and the mixture was stirred at 90° C. and normal pressure for 2 hours for adsorption treatment. Thereafter, filtration was performed using filter paper, but the filtration performance was extremely low. Table 2 shows the properties and filtration rate of the obtained polyol.

[0046]

[Table 2]

[Example 3] Sodium methylate (95 g) was added to 2000 g of polyol C.
% powder) was added and the demethanol reaction was carried out at 11
After carrying out the reaction at 0°C and 10 Torr for 2 hours, 300 g of ethylene oxide was introduced and the reaction was carried out at 110°C for 2 hours. Next, add 23 g of water and 1 portion of acidic sodium pyrophosphate.
Add 9.6 g (1.2 equivalents to sodium),
After neutralization treatment was performed at 110° C. and normal pressure for 1 hour, dehydration treatment was performed at the same temperature and 10 Torr for 2 hours. After that, 115g of water and 115g of synthetic magnesium silicate.
was added and stirred for 2 hours at 90° C. and normal pressure for adsorption treatment, and then filtered using filter paper. After filtration, 120 °C, 2
Dehydration was performed under reduced pressure at 0 Torr for 2 hours to obtain a purified polyol. Its properties and filtration rate are shown in Table 3.

[Comparative Example 3] Ethylene oxide was reacted in the same manner as in Example 3 using 2000 g of polyol C, and then neutralization treatment and dehydration treatment were performed under the same conditions as in Example 3. Thereafter, adsorption treatment and filtration were performed in the same manner as in Example 3 using only synthetic magnesium silicate without using water to obtain a purified polyol. Its properties and filtration rate are shown in Table 3.

[0049]

[Table 3]

[0050]

According to the present invention, polyethers containing fewer impurities such as catalyst decomposition products can be obtained from polyethers synthesized using a multimetal cyanide complex catalyst. Moreover, since it is a method with high filterability, the purification efficiency is high and the product yield is also good. This method is particularly suitable for producing polyethers having oxyethylene groups at the ends.

Claims (4)

[Claims] Claim 1: In the presence of a multimetal cyanide complex catalyst, an initiator having at least one hydroxyl group has 3 carbon atoms.
Polyethers containing the catalyst obtained by ring-opening addition reaction of the monoepoxide described above are treated with a treatment agent made of an alkali metal or its compound to deactivate the catalyst, and then water and an adsorbent are added. A method for producing polyethers, which comprises performing adsorption treatment in the presence of water, followed by filtration to remove the adsorbent, and then dehydration treatment. 2. The method according to claim 1, wherein the alkali metal or its compound is at least one compound selected from an alkali metal element, an alkali metal hydride, an alkali metal alcoholate, and an alkali metal hydroxide. 3. In the presence of a multimetal cyanide complex catalyst, the initiator having at least one hydroxyl group has 3 carbon atoms.
Polyethers containing the catalyst obtained by ring-opening addition reaction of the monoepoxides described above are treated with a treatment agent made of an alkali metal or its compound to deactivate the catalyst, and then the polyether is A method for producing polyethers, which comprises reacting ethylene oxide with ether, then adding water and an adsorbent, performing an adsorption treatment in the presence of water, filtering to remove the adsorbent, and then dehydrating. 4. The method according to claim 3, wherein the alkali metal or its compound is at least one compound selected from an alkali metal element, an alkali metal hydride, an alkali metal alcoholate, and an alkali metal hydroxide.