JPH0517569A - Production of polyethers - Google Patents

Abstract

PURPOSE:To produce a polyether having a high ratio of primary hydroxy group. CONSTITUTION:Propylene oxide is subjected to ring opening addition to a polyoxypropylene triol having 1,000 molecular weight in the presence of a compounded metal cyanide complex catalyst and N,N-dimethylacetamide and then the reactional product is allowed to react with ethylene oxide to produce a polyether. Conversion of a terminal hydroxyl group of polyether into primary hydroxy group, which has been substantially impossible, can be carried out.

Description

Detailed Description of the Invention

[0001]

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]

Polyethers such as polyoxyalkylene polyols obtained by subjecting an initiator to a ring-opening reaction of monoepoxides such as alkylene oxides are used as raw materials for synthetic resins such as polyurethane, surfactants, lubricants and other applications. Widely used in. The initiator is A-
(H) _n is a hydroxyl group-containing compound represented by (A: a residue of a hydroxyl group-containing compound from which a hydrogen atom is removed, n: an integer of 1 or more).

Examples of the initiator include monohydric alcohols, polyhydric alcohols, monohydric phenols and polyhydric phenols. Further, compounds having a hydroxyalkylamino group (alkanolamines, amines-alkylene oxide adducts, etc.) are also used as the initiator. Further, polyethers obtained by reacting the above initiator with a monoepoxide are also used as the initiator.

Polyethers are the following compounds obtained by subjecting the above initiators to a ring-opening addition reaction of a monoepoxide. A [-(R-O) _m -H] _n R-O: monoepoxide ring-opening unit m, n: an integer of 1 or more

Conventionally, a method of reacting a monoepoxide in the presence of an alkali catalyst has been widely used as a method for producing polyethers. Alkali metal compounds such as potassium hydroxide and sodium hydroxide have been used as alkali catalysts. Further, the purification of polyethers using them as a catalyst has been carried out by neutralization with a neutralizing agent such as phosphoric acid or carbon dioxide, or adsorption treatment with an adsorbent such as magnesium silicate or aluminum silicate.

However, when producing polyethers using an alkali catalyst, unsaturated epoxides, particularly unsaturated monools produced by isomerization of propylene oxide, become initiators, and unsaturated monoethers to which monoepoxides are added. (Hereinafter, this is called unsaturated monool) tends to be generated.

Particularly, the proportion of isomerization increases as the molecular weight of polyethers increases, and this tendency becomes remarkable when the molecular weight is 6500 or more (in the case of trifunctional). Therefore, when propylene oxide is used as the monoepoxide, the molecular weight is The synthesis of more than 6500 polyethers was virtually impossible.

It is known to produce polyethers using complex metal cyanide complexes as catalysts (US 32
78457, US 3278458, US 3278459), but this catalyst produces less unsaturated monool and is also capable of producing extremely high molecular weight polyethers.

[0009]

However, it has been difficult to carry out an addition reaction of ethylene oxide with a hydroxyl group at the terminal of a polyether group using the above-mentioned complex metal cyanide complex catalyst. When a mixed metal cyanide complex is used as a catalyst and ethylene oxide is continuously supplied to polyethers obtained by ring-opening reaction of a monoepoxide having 3 or more carbon atoms to an initiator, polyethylene glycol which is a homopolymer of ethylene oxide is produced, Polyethylenes No uniform addition of ethylene oxide to the terminal hydroxyl groups.

On the other hand, there is known a method of treating a complex metal cyanide complex catalyst with an alkali to deactivate the catalyst, then adding ethylene oxide, and then removing the catalyst residue. In this case, ethylene oxide is added to the hydroxyl group at the end of the polyether by the action of the alkali catalyst. As a method of treating with alkali, alkali metal or alkali metal hydroxide (US 4355188), alkali metal hydride (U
S 4721818) is known.

However, this method is a complicated method because it requires the use of two different catalysts. Moreover, when using an alkali metal simple substance or an alkali metal hydride, there is a danger in handling, and when using an alkali metal hydroxide, especially when the polyethers have a high molecular weight, the dehydration treatment takes time. There are problems such as this.

[0012]

The present invention provides the following inventions to solve the above-mentioned problems.

That is, ethylene oxide is reacted with polyethers having at least one hydroxyl group in the presence of a complex metal cyanide complex catalyst and a solvent having a solubility parameter δ represented by the formula 3 of 10 or more. And a method for producing polyethers having a high proportion of primary hydroxyl groups.

[0014]

[Equation 3]

In Equation 3, Δe _i and Δv _i represent the evaporation energy and the molar volume of the atom or atomic group, respectively.

In the present invention, particularly when polyethers produced by using a complex metal cyanide complex catalyst are used as the polyethers before reacting with the above-mentioned ethylene oxide, the polyethers are directly purified without purification. It is advantageous because the invention can be implemented.

Therefore, the present invention also provides a polyether obtained by subjecting an initiator having at least one hydroxyl group to a ring-opening addition reaction of a monoepoxide having 3 or more carbon atoms in the presence of a double metal cyanide complex catalyst. A complex metal cyanide complex catalyst and a solvent having a solubility parameter δ represented by Formula 3 of 10 or more in the presence of a solvent, ethylene oxide is reacted with a polyether having a high proportion of primary hydroxyl groups. It is a manufacturing method.

When using a polyol produced in advance, a monoepoxide having 3 or more carbon atoms is introduced into the reaction system before the reaction with ethylene oxide, and then ethylene oxide is reacted.

Further, the above-mentioned polyethers in the present invention are not limited to those produced in advance, and are produced by using a double metal cyanide complex catalyst in a reaction system containing a solvent in the present invention, Then ethylene oxide may be reacted. That is, an initiator having at least one hydroxyl group is reacted with a monoepoxide having 3 or more carbon atoms in the presence of a complex metal cyanide complex catalyst and a solvent having a solubility parameter δ represented by the formula 3 of 10 or more, and then , A method for producing polyethers having a high proportion of primary hydroxyl groups, which comprises reacting ethylene oxide.

It has been widely practiced to produce polyethers by reacting an initiator with a mixture of ethylene oxide and a monoepoxide such as propylene oxide using an alkali catalyst.

It has also been widely practiced to react polyethers having a low proportion of primary hydroxyl groups with ethylene oxide in the presence of an alkali catalyst to increase the proportion of primary hydroxyl groups.

Since ethylene oxide is more reactive than other monoepoxides, in the former case ethylene oxide tends to react faster than other monoepoxides, so that the end groups of the resulting polyethers are different from those of other monoepoxides. The proportion of epoxide residues is high, and thus the proportion of primary hydroxyl groups is low.

Also in the latter case, when other monoepoxide is mixed with ethylene oxide and reacted, the proportion of primary hydroxyl groups becomes much lower than in the case where both are assumed to react uniformly.

On the other hand, as described above, even when an attempt is made to react ethylene oxide with polyethers using a complex metal cyanide complex as a catalyst, polyethylene glycol, which is a homopolymer of ethylene oxide, is produced, and polyethers end hydroxyl groups are formed. There is no uniform addition of ethylene oxide to the.

According to the method of the present invention, a homopolymer of ethylene oxide is not produced, and ethylene oxide uniformly reacts with the end groups of the polyethers to obtain polyethers having a high primary hydroxyl group ratio. .

The present invention will be described in more detail below. The complex metal cyanide complex in the present invention is considered to have the structure of the following general formula (1) as shown in the above-mentioned known examples.

M ¹ _a [M ² _x (CN) _y ] _b (H ₂ O) _c R _d (1) where M ¹ is Zn (II), Fe (II), Fe (III), Co
(II), 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., M ² is Fe (II),
Fe (III), Co (II), Co (III), Cr (II), Cr (I
II), Mn (II), Mn (III), Ni (II), V (IV), V
(V) etc., R is an organic ligand, a, b, x and y are positive integers that vary depending on the valence and coordination number of the metal, and c and d are coordination numbers to the metal. Is a positive number that depends on.

In the general formula (1), M ¹ is preferably Zn (II), and M ² is Fe (II), Fe (III), Co (II), Co (II).
I) and the like are preferable. Examples of the organic ligand include ketone, ether, aldehyde, ester, alcohol and amide.

The complex metal cyanide complex represented by the general formula (1) includes a metal salt M ¹ X _a (M ¹ _, a is the same as described above, X is an anion forming a salt with M ¹ ) and polycyanometallate. (Salt) Z _e [M ² _x (CN) _y ] _f (M ² , x and y are the same as above. Z is hydrogen, an alkali metal, an alkaline earth metal or the like, and e and f are Z and M ² (A positive integer determined by the valence and coordination number of) or a mixed solvent solution of water and an organic solvent is mixed, and the obtained complex metal cyanide is brought into contact with the organic ligand R, It is prepared by removing excess solvent and organic ligand R.

Polycyanometallate (salt) Z _e [M ² _x (C
In N) _y ] _f , various metals including hydrogen and alkali metals can be used as Z, but lithium salt, sodium salt, potassium salt, magnesium salt, and calcium salt are preferable. Particularly preferred are conventional 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. Further, the reaction can be carried out while gradually adding the monoepoxide to the reaction system. The reaction occurs even 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 the initiator used.
About 5000 ppm is suitable, and 30 to 1000 ppm is more preferable. Regarding the introduction of the catalyst into the reaction system, it may be introduced all at once, or may be introduced sequentially in a divided manner.

As the polyether before the reaction with ethylene oxide in the present invention, the polyoxyalkylene polyol produced by using the above catalyst is preferable. The polyoxyalkylene polyol is obtained by sequentially subjecting an initiator having at least two hydroxyl groups to a monoepoxide such as alkylene oxide to undergo ring-opening addition reaction.

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 tetrahydric or higher alcohols 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 alkylene oxide.

Further, a compound having a phenolic hydroxyl group or a methylol group such as bisphenol A, resole or novolac, a compound having a hydroxyl group such as ethanolamine or diethanolamine and another active hydrogen, and a monoepoxide such as an alkylene oxide are reacted therewith. There are polyethers having a lower molecular weight than the target product obtained by the above process.

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 nitrogen atoms with a monoepoxide such as alkylene oxide. In addition, phosphoric acid and its derivatives, and other polyhydroxy compounds can also be used. Two or more of these polyhydroxy compounds can 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 an alkylene oxide ring-opening reaction. Examples of monovalent initiators include methanol, ethanol, butanol, hexanol, other monools, phenols, phenol derivatives such as alkyl-substituted phenols,
Further, there are polyethers having a lower molecular weight than the intended product obtained by reacting these with a monoepoxide such as alkylene oxide.

Further, 1 hydrogen atom bonded to the nitrogen atom
There are polyethers having a lower molecular weight than a target product obtained by reacting a monoamine or a polyamine having a unit with a monoepoxide such as an alkylene oxide.

As the monoepoxide having 3 or more carbon atoms for producing polyethers before reacting with ethylene oxide, an alkylene oxide having 3 to 4 carbon atoms is preferable, and propylene oxide is particularly preferable. When two or more kinds of alkylene oxides are used, they can be mixed and added or sequentially added to form a random polymer chain or a block polymer chain.

In the present invention, the polyethers before reacting with ethylene oxide are not necessarily limited to the polyethers obtained by using the complex metal cyanide complex as a catalyst, but other catalysts such as alkali can be used. Polyethers produced using a catalyst can be used.

In the present invention, polyethers produced and purified in advance can also be used. In this case, the monoepoxide having 3 or more carbon atoms is reacted before the ethylene oxide is reacted, and then the ethylene oxide is reacted.

However, the polyethers obtained by using the double metal cyanide complex as a catalyst are advantageous because they can be subsequently reacted with ethylene oxide.

Further, in the reaction system containing the solvent in the present invention, at least 1 is used by using the double metal cyanide complex catalyst.
It is also possible to react an initiator having one hydroxyl group with a monoepoxide having 3 or more carbon atoms to produce polyethers, and subsequently react with ethylene oxide.

As the initiator having at least one hydroxyl group and the monoepoxide having 3 or more carbon atoms, those which can be used in producing the above-mentioned polyethers before reacting with ethylene oxide can also be used.

In the present invention, the solubility parameter δ is a characteristic value of the liquid, which is a measure of the miscibility of the liquid. Fe
The method of dors et al. [RFFedors: Polym.Eng.Sci., 14 [2], 147
(1974)], the solubility parameter is expressed by the following equation 4.

[0045]

[Equation 4]

In Equation 4, Δe _i and Δv _i represent the evaporation energy and the molar volume of the atom or atomic group, respectively.

The solvent in the present invention has a solubility parameter δ at 25 ° C. of 10 or more. Specific examples include N, N-dimethylacetamide (δ = 10.6
0), N, N-dimethylformamide (δ = 10.6
3) and the like, but not limited thereto. or,
For example, tetrahydrofuran (δ = 8.99) and ter-butanol (δ = 9.74) are used as the solvent of the present invention.
Not suitable.

The amount of the solvent used is preferably 0.1 to 50% by weight, more preferably 0.1 to 20% by weight, based on the polyethers that react with ethylene oxide. The most preferred amount used is 0.1 to 50% by weight.

The molecular weight of the polyethers before reacting with the ethylene oxide is not particularly limited, but is preferably about 80 or less in terms of hydroxyl value. The lower limit is preferably about 5. Particularly, polyoxyalkylene polyol having a hydroxyl value of 5 to 60 is preferable.

For the purpose of the present invention, it is necessary that the polyethers before the reaction with the above ethylene oxide have a low proportion of primary hydroxyl groups. Although not particularly limited, the proportion of primary hydroxyl groups is suitably 50% or less, and particularly preferably 30% or less. The proportion of primary hydroxyl groups in polyethers obtained by ring-opening addition polymerization of only propylene oxide using a complex metal cyanide complex is usually 15
% Or less.

After reacting with ethylene oxide, it is usually necessary to remove the complex metal cyanide complex used as catalyst from the obtained polyethers. As a method of removing the catalyst, for example, there is a method of deactivating the catalyst by adding an alkali, treating the deactivated catalyst component or alkali with an adsorbent or an ion exchange resin, and removing them by filtration or the like.
However, the method for removing the complex metal cyanide complex is not limited to these.

The molecular weight of the finally obtained polyethers is not particularly limited. However, a product that is liquid at room temperature is preferable from the viewpoint of its application. The hydroxyl value of the polyethers is preferably about 70 or less, more preferably 5 to 40. The number of hydroxyl groups is the same as the number of hydroxyl groups of the polyethers before the reaction of the ethylene oxide-containing mixture, and is 1 or more, preferably 2 to 8 and particularly preferably 2 to 6.

The polyethers obtained by the present invention are
It is most useful as a polyol for a polyurethane raw material used alone or in combination with other polyethers. The polyethers obtained by the present invention are also used as raw materials for synthetic resins other than polyurethane and as additives. Further, it can be used as a lubricating oil, an insulating oil, a hydraulic oil, other oils, or as a raw material thereof. Furthermore, the polyethers obtained by the present invention can be converted into other compounds such as alkyl ether compounds and acyl compounds to be used for various purposes.

[0054]

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

Example 1 40 g of polyoxypropylene triol having a molecular weight of 1000, 0.020 g of zinc hexacyanocobaltate catalyst (500 ppm with respect to the initiator triol) and 0.40 g of N, N-dimethylacetamide (1 with respect to the initiator). %) Was charged into the reactor, the nitrogen was sufficiently replaced, and then the temperature was raised to 120 ° C. After this, propylene oxide (hereinafter referred to as PO) 80
g was supplied and the reaction was carried out. After the molecular weight reached 3000, 10 g of ethylene oxide (hereinafter referred to as EO) was added and the reaction was carried out at 120 ° C. for 4 hours. The obtained polyol was slightly orange and transparent, and its primary hydroxyl group ratio was 42%.

[Comparative Example 1] The same procedure as in Example 1 was carried out except that N, N-dimethylacetamide was not used. The obtained polyol was cloudy and had a primary hydroxyl group ratio of 21.
%Met.

Example 2 50 g of polyoxypropylene triol having a molecular weight of 10,000, 0.015 g of zinc hexacyanocobaltate catalyst (300 ppm with respect to the initiator triol), 0.50 g of N, N-dimethylacetamide (1 with respect to the initiator). %) And 5.0 g
PO was charged into the reactor, the nitrogen was sufficiently replaced, and then the temperature was raised to 120 ° C. 5.0 g of EO was added to this, and it reacted at 120 degreeC for 4 hours. The obtained polyol was slightly orange and transparent, and its primary hydroxyl group ratio was 39%.

[Comparative Example 2] The same procedure as in Example 2 was carried out except that N, N-dimethylacetamide was not used. The polyol obtained was cloudy and had a primary hydroxyl group ratio of 12
%Met.

Example 3 100 g of polyoxypropylene triol having a molecular weight of 10,000, 0.050 g of zinc hexacyanocobaltate catalyst (500 ppm with respect to the initiator triol), 2.0 g of N, N-dimethylformamide (2 with respect to the initiator). %) And 8.0 g
PO was charged into the reactor, the nitrogen was sufficiently replaced, and then the temperature was raised to 120 ° C. 7.0 g of EO was added to this, and it reacted at 120 degreeC for 4 hours. The obtained polyol was slightly orange and transparent, and its primary hydroxyl group ratio was 27%.

Comparative Example 3 The procedure of Example 2 was repeated except that tetrahydrofuran was used instead of N, N-dimethylformamide. The obtained polyol was cloudy and its primary hydroxyl group ratio was 11.5%.

[0061]

INDUSTRIAL APPLICABILITY The present invention makes it possible to primaryize the terminal hydroxyl groups of polyethers, which has not been practically possible by using the conventional composite metal cyanide complex catalyst. Therefore, by applying the present invention when producing polyethers using a double metal cyanide complex catalyst, polyethers having a high proportion of primary hydroxyl groups can be easily produced.

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Shigeyuki Ozawa             1150 Hazawa-machi, Kanagawa-ku, Yokohama-shi, Kanagawa             Asahi Glass Co., Ltd. Central Research Laboratory

Claims (6)

[Claims] 1. A method of reacting ethylene oxide with a polyether having at least one hydroxyl group in the presence of a complex metal cyanide complex catalyst and a solvent having a solubility parameter δ represented by the formula 1 of 10 or more. Characteristic 1
A method for producing polyethers having a high proportion of primary hydroxyl groups. [Equation 1] In this formula 1, Δe _i and Δv _i represent the evaporation energy and the molar volume of the atom or atomic group, respectively. 2. Polyethers obtained by subjecting an initiator having at least one hydroxyl group to a ring-opening addition reaction of a monoepoxide having 3 or more carbon atoms in the presence of a complex metal cyanide complex catalyst. The manufacturing method according to claim 1. 3. The process according to claim 1, wherein a monoepoxide having 3 or more carbon atoms is introduced into the reaction system before the reaction with ethylene oxide, and then ethylene oxide is reacted. 4. An initiator having at least one hydroxyl group in the presence of a complex metal cyanide complex catalyst and a solvent having a solubility parameter δ represented by the formula 2 of 10 or more,
A method for producing polyethers having a high proportion of primary hydroxyl groups, which comprises reacting a monoepoxide having 3 or more carbon atoms and then reacting with ethylene oxide. [Equation 2] In Equation 2, Δe _i and Δv _i represent the evaporation energy and the molar volume of an atom or atomic group, respectively. 5. The method according to claim 1, wherein the solvent having a solubility parameter δ of 10 or more is N, N-dimethylformamide or N, N-dimethylacetamide. 6. The amount of the solvent used is 0.1% of the polyethers.
The manufacturing method according to claim 1 or 4, wherein the content is -50% by weight.