JP2960460B2 - Method for producing polyethers - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for producing a polyether, and more particularly to a method for producing a polyether polyol.

[Prior art] Polyethers obtained by subjecting an initiator to a ring-opening reaction of a monoepoxide such as an alkylene oxide 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 AH) _n (A; a residue of the hydroxyl group-containing compound excluding the hydrogen atom of the hydroxyl group, n; an integer of 1 or more). As an initiator, for example, 1
There are polyhydric alcohol, polyhydric alcohol, monohydric phenol, polyhydric phenol and the like. Compounds having a hydroxyalkylamino group (alkanolamines, amines-alkylene oxide adducts, etc.) are also used as initiators. Further, polyethers obtained by reacting the above initiator with monoepoxide are also used as the initiator.

The polyethers are the following compounds obtained by subjecting the above initiator to multiple ring-opening addition reaction of monoepoxide.

AR-O _m H] _n RO: Monoepoxide ring-opened reaction unit m: integer Conventionally, as a method for producing polyethers, a method of reacting monoepoxide in the presence of an alkali catalyst has been widely used. As the alkali catalyst, an alkali metal compound such as potassium hydroxide or sodium hydroxide has been used. However, polyethers obtained using an alkali catalyst have the following problems. That is, monoepoxides, particularly unsaturated monols formed by isomerization of propylene oxide, serve as initiators, and unsaturated polyether monols (hereinafter also referred to as unsaturated monols) formed by ring-opening addition of monoepoxides thereto. I do.

As the molecular weight of polyethers increases, the ratio of isomerization increases, and this tendency becomes remarkable when the molecular weight is 6500 or more (in the case of trifunctionality). Therefore, when propylene oxide is used as the monoepoxide, the polyether with a molecular weight of 6500 or more is used. The synthesis of the class was virtually impossible.

On the other hand, it is known to produce polyethers using double metal cyanide complexes as catalysts (US 32784).
57, US 3278458, US 3278459, US 3427256, US 3427334, US
3427335). This catalyst generates little of the above-mentioned unsaturated monool, and can also produce very high molecular weight polyethers.

[Problems to be Solved by the Invention] However, the double metal cyanide complex catalyst has the following two problems. First, it was difficult to remove the catalyst from polyethers obtained by ring-opening a monoepoxide having 3 or more carbon atoms with an initiator using a double metal cyanide complex as a catalyst. Neither can the catalyst be separated by filtration, nor can it be separated by adsorption with an adsorbent such as activated carbon.

Therefore, in order to remove this catalyst from polyethers using a double metal cyanide complex, simply filtration or
In addition to treatment with an adsorbent or the like, it is necessary to decompose the catalyst with an alkali or acid and ionize it, and then remove these decomposed products, residual alkali and residual acid by adsorption or filtration.

Second, it was difficult to react ethylene oxide with a hydroxyl group using a double metal cyanide complex as a catalyst. When a double metal cyanide complex is used as a catalyst and ethylene oxide is fed to the initiator and then to a polyether obtained by ring-opening reaction of a monoepoxide having 3 or more carbon atoms, polyethylene glycol which is a homopolymer of ethylene oxide is obtained. Produced and does not uniformly add ethylene oxide to polyethers terminal hydroxyl groups.

There are known a method of treating a double metal cyanide complex catalyst with an alkali to deactivate the catalyst and remove the catalyst residue, and a method of adding an ethylene oxide after the alkali treatment and then removing the catalyst residue. As a method of treating with an alkali, there are alkali metals and alkali metal hydroxides (Japanese Patent Publication No.
A method using an alkali metal hydride (see Japanese Patent Application Laid-Open No. 1-229035) is known. The present inventors have found a method using an alkali metal alcoholate (see Japanese Patent Application No. 1-331158). However, after the treatment with an alkali metal (compound) (or after further reaction with ethylene oxide), the deactivated catalyst component or treating agent (ie, alkali metal or its compound) contained in the obtained polyethers It was not easy to remove the components from the polyethers. The above publication describes a method using an adsorbent or a method using an ion exchange resin as a removing method.

However, these methods are complicated in steps, cannot be said to have sufficient removal efficiency, and are economically disadvantageous. For example,
When an adsorbent such as synthetic magnesium silicate is used, a high-purity product requires a large amount of adsorbent, low filtration efficiency, and low product yield. Further, in the case of the ion exchange method or the solvent extraction method, the equipment cost and the operating cost are high and are not industrially practical.

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

An alkali metal or alkali metal compound is added to a polyether containing the above catalyst obtained by subjecting an initiator having at least one hydroxyl group to a ring-opening addition reaction with a monoepoxide having 3 or more carbon atoms in the presence of a double metal cyanide complex catalyst. Wherein the catalyst is deactivated by adding a treating agent consisting of the following, and then an organic acid is added to precipitate an organic acid salt, which is removed from the polyether.

An alkali metal or alkali metal compound is added to a polyether containing the above catalyst obtained by subjecting an initiator having at least one hydroxyl group to a ring-opening addition reaction with a monoepoxide having 3 or more carbon atoms in the presence of a double metal cyanide complex catalyst. To deactivate the catalyst, then react the ethylene oxide with the polyether as an initiator, and then add an organic acid to the resulting polyether to form an organic acid salt. A method for producing polyethers, comprising precipitating and removing the same from the polyethers.

It is considered that the double metal cyanide complex in the present invention has the structure of the following general formula (1) as shown in the above-mentioned known examples.

M _a [M ′ _x (CN) _y ] _b (H ₂ O) _c (R) _d (1) where M is Zn (II), Fe (II), Fe (III), Co (I
I), Ni (II), Al (III), Sr (II), Mn (II), Cr
(III), Cu (II), Sn (II), Pb (II), Mo (IV), M
o (VI), W (IV), W (VI), etc., where M ′ is Fe (I
I), Fe (III), Co (II), Co (III), Cr (II), Cr
(III), Mn (II), Mn (III), Ni (II), V (IV),
V (V), etc., R is 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 the coordination of the metal. It is a positive number that changes depending on the number.

M in the general formula (1) is preferably Zn (II), and M ′ is
Fe (II), Fe (III), Co (II), Co (III) and the like are preferable. Examples of the organic ligand include ketone, ether, aldehyde, ester, alcohol, and amide.

As described above, the double metal cyanide complex represented by the general formula (1) is composed of a metal salt MXa (M, a is the same as described above, X is an anion forming a salt with M) and polycyanometallate (salt)
_Ze [ _M'x (CN) _y ] _f (M ', x, y is the same as above. Z is hydrogen, alkali metal, alkaline earth metal, etc., e, f is the valence and distribution of Z, M' Aqueous solution or a mixed solvent of water and an organic solvent, and contacting the resulting complex metal cyanide with the organic ligand R. Prepared by removing compound R.

For polycyanometallate (salt) _Ze [ _M'x (CN) _y ] _f , various metals such as hydrogen and alkali metals can be used for Z, and lithium, sodium, potassium, Magnesium salts and calcium salts are preferred. Particularly preferred are ordinary alkali metal salts, that is, sodium salts and potassium salts.

Polyethers are usually produced by reacting a mixture of a monoepoxide and an initiator in the presence of a catalyst. In addition, the reaction can be carried out while gradually adding monoepoxide to the reaction system. The reaction occurs at room temperature, but the reaction system can be heated or cooled if necessary. The amount of the catalyst used is not particularly limited, but is 1 to 5000 pp based on the initiator used.
m is appropriate, and 30 to 1000 ppm is more preferable. The catalyst may be introduced into the reaction system in a lump at first, or may be divided and introduced sequentially.

By using this double metal cyanide complex catalyst, it is possible to synthesize polyethers having a low unsaturated monool content or an extremely high molecular weight having a low unsaturated monool content.

As the alkali metal or alkali metal compound in the present invention (hereinafter also referred to as both alkali metal and the like),
The known compounds include, of course, alkali metal alcoholates. Preferably, a simple substance, hydride, hydroxide, and alcoholate of an alkali metal selected from sodium and potassium are used. An aqueous solution thereof can be used as the hydroxide. Alcoholates of monohydric or polyhydric alcohols are suitable as alcoholates. As the alcohol, a low-boiling alcohol is preferable. This is because it is very easy to remove by-produced alcohol after the reaction between the polyether and the alcoholate. Therefore, the alcohol is preferably a lower monol, especially methanol or ethanol. These metal methylates and ethylates are easy to handle and treat, and are industrially easy to use as treating agents.
The alcoholates of sodium and potassium used here are
A solution diluted as an alcohol solution or a powder alone can be used.

As a method of treating a polyether containing a double metal cyanide complex catalyst with an alkali metal or the like, an alkali metal or the like is added, and the mixture is preferably heated to 40 to 180 ° C., particularly 60 to 150 ° C., and dehydration or dealcoholation is performed as necessary. For this reason, a method of performing a reduced pressure treatment (this reduced pressure treatment may be performed after purification) and then performing a purification is preferable. In the case of reacting ethylene oxide, a method of adding an alkali metal or the like, heating the mixture in the same manner, performing a reduced pressure treatment to remove water and alcohol produced as a by-product, reacting the ethylene oxide, and then performing purification is preferable. The complex metal cyanide complex catalyst before the treatment with the alkali metal or the like is partially or wholly dissolved in the polyether. When this is treated with an alkali metal or the like, the complex metal cyanide complex is considered to be a complex salt insoluble in polyethers. This complex salt is dispersed in polyethers in the form of ultrafine particles, and it is difficult to separate the complex salt from the polyethers by filtration or the like.

The present invention is characterized in that an organic acid is used in the purification / separation step. The organic acid reacts with a reacted or unreacted component such as an alkali metal to form a salt. The present inventor has found that when this salt is formed, the double metal cyanide complex component (such as the above complex salt) is easily incorporated into this salt. In particular, when a small amount of water is added to the polyethers together with the organic acid, and heat treatment is performed, followed by dehydration, crystals of the organic acid salt precipitate, and the double metal cyanide complex component is almost completely incorporated into the salt. It is. The amount of this water is preferably 0.1 to 10% by weight, particularly preferably 1 to 5% by weight, based on the polyethers. The amount of the organic acid is sufficient if it is at least approximately equivalent to the alkali metal, but is preferably about 1-2.
Double equivalents, especially 1 to 13 equivalents are preferred. The temperature at the time of heat treatment by adding an organic acid is 40 to 200 ° C., particularly 60 ° C.
~ 150 ° C is preferred. As the organic acid, various organic acids capable of forming an alkali metal salt can be used, and carboxylic acid is particularly preferable. Among them, carboxylic acids having a low boiling point and carboxylic acids having a melting point in the above-mentioned processing temperature range are preferable. In the former, unreacted substances can be removed by a reduced pressure treatment, and in the latter, unreacted substances can be precipitated and removed. Examples of the carboxylic acid include formic acid, acetic acid, oxalic acid, succinic acid, adipic acid, maleic acid, and benzoic acid. Adipic acid is most preferred because it forms a salt that is particularly easy to incorporate the double metal cyanide complex component.

After the treatment with the organic acid, solids such as precipitated crystals are separated from the polyethers. Filtration is generally and preferably used as this separation method, but is not necessarily limited to this method.

The polyethers obtained by the method of the present invention are preferably polyoxyalkylene polyols. The polyoxyalkylene polyol is obtained by sequentially performing a ring-opening addition reaction of a monoepoxide such as an alkylene oxide to an initiator having at least two hydroxyl groups. As the initiator, a polyhydroxy compound having 2 to 8 hydroxyl groups is particularly preferable. Examples of the polyhydroxy compound include dihydric alcohols such as ethylene glycol and propylene glycol, trihydric alcohols such as glycerin, trimethylolpropane and hexanetriol, and tetravalent or higher valents such as pentaerythritol, diglycerin, dextrose, sorbitol and sucrose. There are alcohols and polyethers having a lower molecular weight than the target product obtained by reacting these alcohols with a monoepoxide such as an alkylene oxide. Compounds having a phenolic hydroxyl group or a methylol group such as bisphenol A, resole and novolak, compounds having a hydroxyl group such as ethanolamine and diethanolamine and other active hydrogens, and compounds obtained by reacting these with a monoepoxide such as an alkylene oxide. There are polyethers of lower molecular weight than the desired product. Further, 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 an alkylene oxide. In addition, phosphoric acid, its derivatives, and other polyhydroxy compounds can also be used. These polyhydroxy compounds may be used in combination of two or more.

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

The monoepoxide in the present invention is a monoepoxide having 3 or more carbon atoms, particularly preferably an alkylene oxide having 3 or more carbon atoms. More preferably, it has 3 to 4 carbon atoms such as propylene oxide, 1,2-butylene oxide, 2,3-butylene oxide and epichlorohydrin.
Are preferred, and propylene oxide is most preferred. They can be used alone or in combination of two or more thereof and other monoepoxides such as styrene oxide, glycidyl ether, and glycidyl ester. When two or more alkylene oxides are used or when an alkylene oxide and another monoepoxide are used, they can be mixed and added or sequentially added to form a random polymerized chain or a block polymerized chain.

However, even if an initiator or a polyether is allowed to react directly with ethylene oxide using a double metal cyanide complex as a catalyst, polyethylene glycol which is a homopolymer of ethylene oxide is generated. Therefore, for example, using this catalyst to copolymerize ethylene oxide with other monoepoxides, or reacting ethylene oxide with polyethers obtained using a double metal cyanide complex as a catalyst to react primary oxide It is usually not possible to obtain polyethers having a high proportion of However, a hydroxy compound having an oxyethylene group, for example, a polyoxyalkylene polyol having an oxyethylene group can be used as the initiator.

According to the method of the present invention, hydroxyl groups of polyethers are alcoholated by treating with an alkali metal or the like,
Next, an oxyethylene group is introduced into the molecular terminal by reacting with ethylene oxide, and the catalyst component is separated as described above to obtain a polyether having a high ratio of primary hydroxyl groups.

The molecular weight of the obtained polyethers is not particularly limited. However, products that are liquid at room temperature are preferred in terms of their use. The reaction amount of monoepoxide with respect to 1 mol of the initiator is preferably at least about 10 mol, and more preferably at least about 50 mol. Still more preferably, the average per initiator hydroxyl groups is at least about
Polyethers obtained by reacting 10 molecules, especially at least about 30 molecules, are preferred. In addition, if expressed in terms of hydroxyl value, 20
0 or less, especially 100 or less is appropriate. 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 preferable. For other uses, for example, oil raw materials such as hydraulic oil, polyether poly (or mono) ol in the above range is preferable.

The polyether polyol obtained by the present invention is most useful as a polyol for a polyurethane raw material used alone or in combination with other polyols. Further, the polyether poly (or mono) ol obtained according to the present invention is also used for raw materials and additives of synthetic resins other than polyurethane. In addition, lubricating oil,
It can be used as insulating oil, hydraulic oil, other oil, or as a raw material thereof. Further, the polyethers obtained according to the present invention can be converted into other compounds such as alkyl ether compounds and acyl compounds to be used for various applications.

Hereinafter, the present invention will be described specifically with reference to Examples and Comparative Examples, but the present invention is not limited to only these Examples.

[Example] The following polyoxypropylene polyol was treated with an alkali metal or the like (then, ethylene oxide was reacted), and then the residue was removed.

The following polyoxypropylene polyol has a molecular weight of about
A polyoxypropylene triol obtained by adding a zinc hexacyanocobaltate complex catalyst to a polyoxypropylene triol of 500 as an initiator, supplying propylene oxide and reacting at about 120 ° C. until a predetermined molecular weight is reached. . The produced polyoxypropylene triol contained the following amounts of metal components as a catalyst.

Polyol A; a polyoxypropylene triol with a molecular weight of 4000 containing zinc hexacyanocobaltate complex (Zn 40 ppm, Co 21 ppm) Polyol B; a polyoxypropylene triol with a molecular weight 6000 containing zinc hexacyanocobaltate complex (Zn 60 ppm, Co 32 ppm) Polyol C; polyoxypropylene triol having a molecular weight of 9000 containing zinc hexacyanocobaltate complex (Zn 80 ppm, Co 39 ppm) Example 1 22.2 g of potassium methylate (30% methanol solution) was added to 1000 g of polyol A, and the methanol removal reaction was carried out. 90 ℃, 2
0 Torr for 2 hours. Then, 10g of water and 7.63 of adipic acid
g (1.1 equivalents to potassium) was added, and the mixture was stirred at 90 ° C. and normal pressure for 1 hour, then degassed at 20 Torr for 2 hours, and then filtered using a filter paper to obtain a transparent polyol. The properties of the obtained polyol are shown in Table 1 below.

Comparative Example 1 In the same manner as in Example 1, 1000 g of polyol A was treated with potassium methylate, and then 50 g of synthetic magnesium silicate was added to remove potassium. After stirring at 90 ° C. and normal pressure for 2 hours, filtration was performed using a filter paper. Done. However, the filter paper was clogged, and only 40% of the polyol after filtration was obtained. The properties of the obtained polyol are shown in Table 1 below.
Shown in

Example 2 5.26 g of sodium methylate (95% powder) was added to 1000 g of polyol B, and the methanol removal reaction was conducted at 90 ° C. and 15 Torr.
r, after 1.5 hours, 200 g of ethylene oxide was added,
The reaction was performed at 90 ° C. for 2 hours. After completion of the reaction, add 10 g of water and 6.0 g of succinic acid (1.1 equivalents to sodium) and add 100 g.
After stirring at room temperature for 1 hour, degas at 20 Torr for 1 hour,
Thereafter, the mixture was filtered using filter paper to obtain a transparent polyol.
The property values of the obtained polyol are shown in Table 2 below.

Comparative Example 2 Ethylene oxide was added to polyol B1 in the same manner as in Example 2.
After reacting to 000 g, 400 g of n-hexane and 150 g of water were added, and the mixture was passed through a cation exchange resin and an anion exchange resin. Next, n-hexane and water were removed under heating vacuum. A slight turbidity was observed in the obtained polyol. The property values of the obtained polyol are shown in Table 2 below.

Example 3 To 2,000 g of polyol C, 8.4 g of sodium methylate (95% powder) was added, and the methanol removal reaction was conducted at 110 ° C. and 10 Torr.
r After 2 hours, add 300 g of ethylene oxide and add
The reaction was performed at 10 ° C. for 2 hours. After completion of the reaction, 10 g of water and 11.3 g of adipic acid (1.05 equivalents to sodium) were added, and the mixture was stirred at 110 ° C. and normal pressure for 1 hour, degassed at 10 Torr for 2 hours, and then filtered using filter paper. A clear polyol was obtained. The property values of the obtained polyol are shown in Table 3 below.

Comparative Example 3 Ethylene oxide was reacted in the same manner as in Example 3 using 2000 g of polyether C. Next, hydrochloric acid and synthetic magnesium silicate were added thereto for purification. The property values of the obtained polyol are shown in Table 3 below.

[Effects of the Invention] The present invention makes it possible to easily separate and remove a double metal cyanide complex catalyst in which an alkali metal or the like is inactivated as a processing agent and a processing agent component from polyethers.
Further, in the case of producing polyethers having a high ratio of primary hydroxyl groups by reacting ethylene oxide with hydroxyl groups of the polyethers after deactivating the double metal cyanide complex catalyst, similarly purified polyethers are used. Can be easily obtained. The method of the present invention is characterized by higher filtration efficiency and higher yield than the conventional method.

Continuation of front page (58) Field surveyed (Int.Cl. ⁶ , DB name) C08G 65/00-65/48

Claims (5)

(57) [Claims] 1. An initiator having at least one hydroxyl group in the presence of a double metal cyanide complex catalyst has 3 carbon atoms.
The above-mentioned monoepoxide is subjected to a ring-opening addition reaction to a polyether containing the above-described catalyst, a treating agent comprising an alkali metal or an alkali metal compound is added to deactivate the catalyst, and then an organic acid is added. A method for producing polyethers, comprising depositing an organic acid salt and removing the same from the polyethers. 2. An initiator having at least one hydroxyl group in the presence of a double metal cyanide complex catalyst has 3 carbon atoms.
The catalyst is deactivated by adding a treating agent comprising an alkali metal or an alkali metal compound to the polyether containing the catalyst obtained by the ring-opening addition reaction of the above monoepoxide, and then deactivating the catalyst, and then the polyether is A process for producing polyethers, comprising reacting ethylene oxide with the initiator as an initiator, adding an organic acid to the resulting polyethers to precipitate an organic acid salt, and removing the salt from the polyethers. 3. The method according to claim 2, wherein a treating agent comprising an alkali metal alcoholate is added to the polyether containing the catalyst and heated, followed by removing the by-produced alcohol, and thereafter reacting ethylene oxide. 4. The method according to claim 1, wherein water is added together with the organic acid.
2 or 3 methods. 5. The method according to claim 1, wherein water is added together with the organic acid and heated, and then the water is degassed under reduced pressure to precipitate an organic acid salt.
2 or 3 methods.