JP2743454B2 - 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 A (H) _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.

Polyethers are the following compounds obtained by subjecting the initiator to a ring-opening reaction of monoepoxide.

AR-O _m H] _n (RO): ring-opened unit of monoepoxide n, m: an integer of 1 or more Conventionally, as a method for producing polyethers, a method of reacting monoepoxide in the presence of an alkali catalyst is known. 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, an unsaturated monool generated by isomerization of monoepoxide, particularly propylene oxide, serves as an initiator, and an unsaturated monoether having monoepoxide added thereto is formed.

As the molecular weight of polyethers increases, the ratio of isomerization increases, and this tendency becomes remarkable when the molecular weight is 5000 or more (in the case of trifunctionality). Therefore, when propylene oxide is used as the monoepoxide, the polyether with a molecular weight of 6000 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). 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.

Second, it was difficult to add ethylene oxide 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 a polyether obtained by a ring-opening reaction of a monoepoxide having 3 or more carbon atoms with an initiator, polyoxyethylene, which is a high molecular weight ethylene oxide, is produced. In addition, uniform addition of ethylene oxide to the end of polyethers does not occur.

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

1. A polyether containing the above catalyst obtained by subjecting an initiator to a ring-opening reaction with a monoepoxide having 3 or more carbon atoms in the presence of a double metal cyanide complex catalyst is treated with a Lewis acid or a treating agent comprising a solution thereof. A process for deactivating the catalyst, and removing the deactivated catalyst component and treating agent component from the polyether.

2. A polyether containing the above catalyst obtained by subjecting an initiator to a ring opening reaction 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 comprising a Lewis acid or a solution thereof. To deactivate the catalyst, and then use the polyethers as an initiator to cause a ring-opening reaction of ethylene oxide, and then remove the deactivated catalyst components and treating agent components from the obtained polyethers. A method for producing a polyether, which comprises:

The double metal cyanide complex used here generally has the following structure, and it is known that polyethers can be obtained using the same.

M _a · M '(CN) _b (H ₂ O) _d · (R) _e (MX) _f [US Pat 3278457,3278458,3278459,3427256,3427334,3
427335] With this catalyst, it is also possible to produce very high molecular weight polyethers with a low content of unsaturated monols.

Polyoxyalkylene polyols have been used together with polyisocyanate compounds as raw materials for polyurethane production. The polyoxyalkylene polyol is produced by adding a monoepoxide, particularly an alkylene oxide, to a polyhydroxy compound, an amine compound, or another active hydrogen compound having at least one active hydrogen. In particular, ethylene oxide, propylene oxide, and polyhydroxy compounds such as ethylene glycol, propylene glycol, glycerin, trimethylolpropane, pentaerythritol, dextrose, and sucrose.
Polyoxyalkylene polyols produced by adding alkylene oxides such as butylene oxide and epichlorohydrin are widely used. In this addition reaction, alkali metal hydroxides such as potassium hydroxide and sodium hydroxide are most commonly used as catalysts, and the use of catalysts such as boron trifluoride and tertiary amine has also been proposed.

However, in polyethers obtained by polymerizing propylene oxide using an alkali catalyst, unsaturated monool is produced as a by-product, and the produced amount increases with the molecular weight of the polyether. There was a problem that the upper limit could be set.

On the other hand, the generation of unsaturated monool is small. As a method for producing polyethers having no or no metal ether, a method using a metal porphyrin (JP-A-61-197631) is known in addition to a method using a double metal cyanide complex. There is a problem and it is not realistic.

In a polyoxyalkylene polyol used as a raw material of polyurethane, it is known that the residual catalyst has an adverse effect on the reaction during the production of polyurethane or on the physical properties of the generated polyurethane. Therefore, in the production of polyoxyalkylene polyol, it is necessary to sufficiently purify the latter half of the production. Conventionally, purification of polyethers using an alkali metal as a catalyst has been performed by neutralization with phosphoric acid, carbon dioxide, or another neutralizing agent, or by adsorption treatment with an adsorbent such as magnesium silicate or aluminum silicate.

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

Alkali metal, alkali metal hydroxide (US Pat. No. 4,355,188) and alkali metal hydride (US Pat. No. 4,718,818) are known as methods for treating with alkali. However, handling of alkali metal alone or alkali metal hydride involves danger in handling. In addition, alkali metal hydroxides are not realistic because, in particular, when polyethers have a high molecular weight, it takes a long time for dehydration treatment.

The Lewis acid according to the present invention is easy to handle and process,
It can also be used industrially as a treating agent. As Lewis acids,
BF ₃ , AlCl ₃ , AlBr ₃ , FeCl ₃ , TiCl ₄ , SnCl ₄ , CrCl _{3 and} other metal and metalloid halides are preferred.

As a method of treating polyethers containing a complex cyanide complex, a Lewis acid or a solution thereof is added, and the mixture is heated to 100 to 150 ° C. to perform a reduced pressure treatment. When adding ethylene oxide, the addition is performed after this treatment, followed by purification. After treatment with a neutralizing agent and an adsorbent in the purification step, the catalyst residue and the acid residue can all be removed from the polyethers by filtration.

The polyethers obtained by the method of the present invention are preferably polyoxyalkylene polyols, which are obtained by adding an alkylene oxide to an active hydrogen compound having at least two active hydrogens. As the active hydrogen compound, a polyhydroxy compound having at least two 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 alcohol and the like. In addition, compounds having a phenolic hydroxyl group or a methylol group such as bisphenol A, resol, and novolak; compounds having a hydroxyl group and other active hydrogen such as ethanolamine and diethanolamine; polyhydroxy compounds and other active hydrogen compounds; Polyhydroxy compounds such as compounds obtained by adding the following alkylene oxides can also be used. In addition, phosphoric acid and its derivatives, amines, and other active hydrogen compounds can also be used. Two or more of these active hydrogen compounds can be used in combination.

As the alkylene oxide, a monoepoxide having 3 or more carbon atoms, that is, an alkylene oxide having 4 or less carbon atoms, such as propylene oxide, 1,2-butylene oxide, and epichlorohydrin, is preferably used alone or in combination of two or more thereof or styrene oxide. Other epoxy group-containing compounds such as glycidyl ether can be used in combination. In the case of using two or more alkylene oxides or using an alkylene oxide and another epoxy group-containing compound, they can be mixed and added or sequentially added to form a random polymerized chain or a block polymerized chain.

However, when ethylene oxide is directly added to the initiator using a composite metal cyanide as a catalyst, a high molecular weight substance, which is a homopolymer of ethylene oxide, is formed, and the ethylene oxide is uniformly added to the end of the initiator. It is impossible to obtain polyethers having a high proportion of OH groups. According to the method of the present invention, it is possible to add poly (ethylene oxide) to an initiator by treating with a Lewis acid to obtain a polyether having a high ratio of primary OH groups.

The present invention is also applicable to a method for producing a polyether monol by subjecting a monovalent initiator to a ring-opening reaction with the above monoepoxide. As the monovalent initiator, for example, phenol derivatives such as methanol, ethanol, butanol, hexanol, other monols, phenols and alkyl-substituted phenols are preferable.

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 a Lewis acid to add ethylene oxide (EO) and remove residues.

Polyol A, zinc hexacyanocobaltate Molecular weight 500 containing catalyst residue (Zn 35 ppm, Co 18 ppm)
Polyoxypropylene triol polyol B having a molecular weight of 700 containing zinc hexacyanocobaltate catalyst residue (Zn 60 ppm, Co 31 ppm)
Polyoxypropylene triol of 0 Polyol C Zinc hexacyanocobaltate Molecular weight 900 containing catalyst residue (Zn80ppm, Co39ppm)
0 Polyoxypropylene triol Example 1 25 g of BF ₃ (20% tetrahydrofuran solution) was added to 1000 g of polyol A, and the solution was removed at 90 ° C. and 20 Torr for 1 hour. Then, 300 g of ethylene oxide was introduced and the reaction was carried out at 100 ° C. for 3 hours. Was done.

After the reaction, the catalyst residue and the acid residue were treated with an adsorbent (synthetic magnesium silicate) and then filtered to obtain a transparent polyol. The property values of the obtained polyol are as follows.

Comparative Example 1 Potassium hydroxide (48% aqueous solution) 11
g was added, and then an EO addition reaction was performed in the same manner as in Example 1. In the dehydration operation, the water content could not be reduced below 0.3%. Further, a white precipitate was observed in the obtained polyol.

Example 2 20 g of AlCl ₃ (30% tetrahydrofuran solution) was added to 1000 g of polyol B, the solvent was removed at 80 ° C. and 20 Torr for 1 hour, and twice the amount of n-hexane was added to the reaction product to 150 ° C. , 3Hr, after the treatment, the supernatant was separated.
-The hexane was separated by distillation to recover the polyether.

Comparative Example 2 Polyol B 1000 g was added to potassium hydroxide (48% aqueous solution) 12
g, and the same processing as in Example 2 was performed. The water content could not be reduced to less than 0.4% by the dehydration operation.

Also, slight turbidity was observed in the obtained polyol.

Example 3 FeCl ₃ (20% methanol solution) 1 in 1000 g of polyol C
2 g was added, the methanol removal reaction was performed at 90 ° C. and 10 Torr for 1 hour, and then 100 g of ethylene oxide was introduced.
Allowed to react for hours.

The reaction product after the tetrahydrofuran 500 g, the H ₂ O 1
After the addition of 00 g, the solution was passed through a cation exchange resin and an anion exchange resin, and finally, tetrahydrofuran and H ₂ O were removed by heating and under vacuum to obtain a transparent product.

Comparative Example 3 Sodium metal (dispersed in mineral oil) was added to polyether C, and a reaction was carried out in the same manner.

 Coloring and turbidity were observed in the obtained polyol.

[Effect of the Invention] Polyethers containing the above-mentioned catalyst obtained by subjecting a monoepoxide having 3 or more carbon atoms to a ring-opening reaction with an initiator using a double metal cyanide complex as a catalyst are formed from a Lewis acid or a solution thereof. By treating with a treating agent to deactivate the catalyst and then removing the deactivated catalyst component and treating agent component by purification, the catalyst component and treating agent component are completely removed from the polyethers. It was also found that after treatment with a treating agent comprising a Lewis acid or a solution thereof, ethylene oxide was added to the terminals of polyethers by subjecting ethylene oxide to a ring opening reaction.

Claims (2)

(57) [Claims] 1. A treating agent comprising a Lewis acid or a solution thereof containing a polyether containing the catalyst obtained by subjecting an initiator to a ring opening reaction of a monoepoxide having 3 or more carbon atoms in the presence of a double metal cyanide complex catalyst. Wherein the catalyst component and the treating agent component are removed from the polyethers. 2. A polyether containing the above catalyst obtained by subjecting an initiator to a ring-opening reaction of a monoepoxide having 3 or more carbon atoms in the presence of a double metal cyanide complex catalyst,
The catalyst is deactivated by treating with a treating agent comprising a Lewis acid or a solution thereof, and then the above polyether is used as an initiator, and ethylene oxide is subjected to a ring-opening reaction, and then deactivated from the obtained polyether. A method for producing polyethers, comprising removing the above-mentioned catalyst component and treating agent component.