JPH0388823A - Purification of polyethers - Google Patents

Abstract

PURPOSE:To purify a polyether by treating the polyether produced by ring opening of a monoepoxide and containing a complex metal cyanide catalyst with an alkaline metal, etc., subsequently carrying out treatment using water and an acidic pyrophosphate and effectively removing the treatment components and the catalyst component. CONSTITUTION:(A) A polyether produced by a ring opening reaction of >=3C monoepoxide due to an initiator in the presence of a complex metal cyanide as a complex catalyst is treated with (B) an alkaline metal or an alkaline earth metal compound to deactivate the above mentioned catalyst. To the resultant material, (C) 0.2-5wt.% water (based on polyether) and (D) an acidic pyrophosphate [e.g. one represented by MxHyP2O7 (M is alkaline metal; x and y are >=1 and x+y=4)] are added and the deactivated catalyst component and the treatment components are removed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a method for purifying polyethers.

[Prior art] Polyethers obtained by ring-opening reaction of monoepoxides such as alkylene oxides as 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-(-)1)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.

These include polyhydric alcohols, monohydric phenols, and polyhydric phenols. Compounds having a hydroxyalkylamine 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 initiator to a ring-opening reaction of monoepoxide.

A -[-(-R-0-)-, HIn R: Ring-opened unit of monoepoxide n, m: Integer of 1 or more Conventionally, after synthesizing polyethers using a multimetal cyanide complex as a catalyst This is treated with sodium, potassium metal, potassium hydroxide, or sodium hydroxide to deactivate the catalyst, and then the polyethers are treated with a mineral acid such as sulfuric acid or phosphoric acid, and the deactivated catalyst components are treated. A method has been proposed in which the agent is precipitated and the polyethers are filtered out (Japanese Patent Laid-Open No. 76028/1983).

[Problems to be Solved by the Invention] Multimetal cyano complexes are suitable as catalysts for producing polyols with a small amount of unsaturated monools and extremely high molecular weights. If present, during polyurethane production, it exhibits a catalytic effect such as the reaction between polyether and polyisocyanate and the formation of allophanate groups, reducing the physical properties of the polyurethane product, so it is necessary to remove the above catalyst component from polyethers. There is. Conventionally, this purification method involves decomposing the catalyst in the polyether into ionic species using an alkaline aqueous solution, etc., then capping the hydroxyl group end of the polyether with ethylene oxide, etc. as necessary, and neutralizing it with a mineral acid such as sulfuric acid. , a method of separating the precipitate by filtration has been adopted, but since the decomposition products of the above-mentioned composite metal cyano complex precipitate as metal hydroxides with extremely poor filterability, it is difficult to separate them using general methods. This method has disadvantages such as the need to add a large amount of filter aid for improvement, and fine precipitates leak through the filtration, significantly reducing the quality of polyethers.

[Means for Solving the Problems] The present invention has been made to solve the above-mentioned problems, and involves causing an initiator to undergo a ring-opening reaction with a monoepoxide having 3 or more carbon atoms in the presence of a multimetal cyanide complex catalyst. The polyethers containing the catalyst obtained by the process are treated with an alkali metal or alkaline earth metal compound to deactivate the catalyst, and then treated with an acidic pyrophosphate in the presence of water. A method for purifying polyethers characterized by removing deactivated catalyst components and processing agent components from a polyether, and a ring-opening reaction of a monoepoxide having 3 or more carbon atoms as an initiator in the presence of a multimetal cyanide complex catalyst. The obtained polyethers containing the catalyst are treated with an alkali metal or alkaline earth metal compound to deactivate the catalyst, and then ethylene oxide is subjected to a ring-opening reaction using the polyether as an initiator, and then in the presence of water. The present invention proposes a method for purifying polyethers, which is characterized by treating the polyethers with an acidic pyrophosphate and then removing deactivated catalyst components and processing agent components from the polyethers.

In purifying polyethers containing multi-metal cyanide complexes, first, an alkali metal or alkaline earth metal compound in an amount sufficient to deactivate the catalyst is added to the polyether containing the catalyst, and the mixture is heated from room temperature under stirring conditions. 150℃
The catalyst is deactivated by mixing at a temperature of . The amount of alkali component to be added varies depending on the amount of catalyst used and the type of alkali component, but for example, if the amount of catalyst in polyethers is about 500 PPM, the amount of alkali component to be added should be 0.1-0.6
It is appropriate to add in a range of wt%, preferably 0.2 to 0.3 wt%.

Alkaline components include Na, K, Ca, Li
. Around 0.1 to 5 wt% water, preferably 0
．． It is appropriate to carry out the heat treatment under conditions in which water is used in an amount of 5 to 2 wt%. Preferred alkaline components are Na or K hydroxide, carbonate, and alcoholade.

The heat treatment time varies depending on the polyethers used, the form of the alkali component, and the temperature conditions, but for example, when treating polyether with a molecular weight of 10,000 containing the above catalyst amount at a temperature of 100 to 140 °C, -3.0 hours, preferably 0.8-1.0 hours is suitable. After the heat treatment is completed, to remove volatile components generated during the above period or water if water has been added in advance.

The volatile components are removed by reducing the pressure to below several 10 Torr at a temperature of 100 to 150°C. This time is 1
~4 hours, preferably 1.5 to 3.0 hours is appropriate. Then, if necessary, the hydroxyl end of the polyether described above is capped with ethylene oxide, and then an acidic pyrophosphate and water are added to perform a purification treatment, or the following predetermined amount of water is present in the polyether in advance. (such as water left over from the above-mentioned dehydration), there is no need to add water.

In the present invention, acid pyrophosphates are Ichimonana M, H, P
, O, (M=K or Na), but if X is less than 1, the aforementioned acidic pyrophosphate will significantly decompose during treatment, forming a phosphate highly soluble in polyethers. If X exceeds 3, it will be necessary to add a large amount of acidic pyrophosphate to neutralize the alkali component. It is appropriate to use something around =y=2.

The amount of acidic pyrophosphate added depends on the polyether to be treated,
Although it varies depending on the type of acidic pyrophosphate, it is usually preferable to add a molar ratio of 0.5 to 1.5, preferably 0.75 to 1.0 to the alkaline component, and the amount added is 0.
．． If the amount is less than 5, the alkali component cannot be sufficiently neutralized, and if the amount is more than 1.5, the acidic pyrophosphate is wasted, which is not appropriate.

The amount of water used in the present invention varies depending on the type and molecular weight of the polyether, but it is usually 0.2 to 5 wt%, particularly 0.2 to 4 wt%, based on the polyether, for example, when the molecular weight is 10 When processing .000 polyether, 0.2-3 wt% based on polyether
, preferably 1 to 2 wt%. Water is 0.
If the amount is less than 2 wt%, the acidic pyrophosphate will not dissolve sufficiently in the polyether and the neutralization reaction with the alkaline component will not proceed sufficiently, and if the amount of water added exceeds the above range, the decomposition of the acidic pyrophosphate will accelerate. This is not preferable because it progresses over time and forms a phosphate salt that is highly soluble in polyether.

In the present invention, the treatment with acid pyrophosphate is preferably carried out in two stages. In the first step, 173 to 115 amounts of pyrophosphate, preferably around 1/4 amount, and the entire amount or close to the total amount of water are added, and the temperature is 90 to 150°C.
and preferably 0.5 to 3 at a temperature of 100 to 130°C.
．． It is advisable to mix with the polyether for 0 hours, preferably 1 to 2 hours. If the temperature is too low, it will take a long time for the neutralization reaction between the acidic picrate and the alkaline component;
If the temperature is 0°C or higher, some of the polyethers will change in quality, so it is necessary to maintain the temperature within the above range.

If the treatment time is too short, neutralization of the acidic pyrophosphate and the alkaline component will be insufficient, and if the treatment time is not too long, the decomposition of the acidic pyrophosphate will proceed, so the treatment must be carried out within the above-mentioned time.

In the present invention, the second stage addition of acid pyrophosphate is
This is performed after the above-mentioned -th stage processing is completed.

In the second stage, the remaining acid pyrophosphate is added in the form of a powder or suspended in a portion of the polyether, but in some cases it may be mixed with a small portion of the water used. Immediately after adding the acidic pyrophosphate, the moisture in the system is degassed under reduced pressure, and the reaction product of the acidic pyrophosphate and the alkaline component and the deactivated catalyst component are incorporated into the acidic pyrophosphate crystals and precipitated. .

By employing the present invention, a precipitate mainly composed of acidic pyrophosphate with good filterability is formed, which contains most of the catalyst moiety and alkaline components in polyether, and the catalyst and alkali components can be removed by normal filtration operations. It becomes possible to produce highly transparent polyethers that do not contain any residue.

In the present invention, synthetic aluminum silicate, synthetic magnesium silicate, activated alumina, synthetic aluminum silicate, synthetic magnesium silicate, activated alumina, Treated with an inorganic adsorbent material such as activated clay or silica gel, the amount of which is contained in the polyether in the range of 0.05 to 3.0%, preferably 0.3 to 1% based on the polyether. Use as appropriate depending on the dissolved components.

As polyethers to which the method of the present invention can be applied, polyoxyalkylene polyols are preferred, and polyoxyalkylene polyols are obtained by adding alkylene oxide to an active hydrogen compound having at least two active hydrogens.

The active hydrogen compound is particularly preferably a polyhydroxy compound having at least two hydroxyl groups. Examples of the polyhydroxy compound include dihydric alcohols such as ethylene glycol and propylene glycol, glycerin,
3 such as trimethylolpropane, hexanetriol, etc.
alcohol, pentaerythritol, diglycerin,
Dextrose, sorbitol.

Examples include alcohols with a valence of four or higher, such as Shake Rose. In addition, compounds having phenolic hydroxyl groups and methylol groups such as bisphenol A, resol, and novolak,
Compounds with hydroxyl groups and other active hydrogen such as ethanolamine and jetanolamine, and polyhydroxy compounds such as compounds obtained by adding less than the desired final amount of alkylene oxide to polyhydroxy compounds and other active hydrogen compounds are also used. can.

In addition, phosphoric acid, its derivatives, amines, and other active hydrogen compounds can also be used. Two or more types of these active hydrogen compounds can also be used.

As the alkylene oxide, monoepoxides having 3 or more carbon atoms, i.e. alkylene oxides having 4 or less carbon atoms such as propylene oxide, 1,2-butylene oxide, and epichlorohydrin, are preferable, and these may be used alone, or in combination with styrene oxide or two or more thereof. Other epoxy group-containing compounds such as glycidyl ether can be used in combination. When using two or more alkylene oxides or alkylene oxide and another compound containing an evixi group, they can be added as a mixture or added sequentially to form a random polymer chain or a block polymer chain. After the multimetal cyanide complex catalyst is deactivated, ethylene oxide is reacted with polyethers using an alkali component as a catalyst.

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

Example 1 Multi-metal cyanide complex synthesized from zinc chloride and alkali metal cyanocobaltate (Zn80, Co40
1% of an aqueous solution of 30 wt% potassium hydroxide was added to polyoxypropylene triol with a molecular weight of 10.000 synthesized using
．． After mixing for 5 hours, the temperature was 120℃ and the pressure was 1 (1~15
It was dehydrated for about 1 hour under Torr conditions. Next, 0.75 times the molar ratio of Na, HxP*O to potassium hydroxide.
0.5 per t and polyol, L, Q, 2.
0.5. Add Owt% of water and 0.5 at a temperature of 120°C.
Stir and mix for an hour. Then 0.2 per sodium hydroxide
5 mol of Na*HsPaOt was added in powder form and dehydrated with stirring under the same temperature conditions and pressure of 10 to 20 Torr to obtain crystals of pyrophosphate containing potassium hydroxide and deactivated composite metal cyanide. The polyether containing these precipitates was separated by filtration using Na5C filter paper. Next, 1.0% by weight of synthetic magnesium silicate (Kyowa Chemical, KW-60O3) was added to the filtered polyether, and after degassing for about 1 hour at a temperature of 120°C, the polyether was filtered again to make it transparent. obtained a polyether with high The results of measuring the filtration rate, CPR, Zn, and Co amount of the polyether are shown in Table 1 of FIG. 1, respectively.

Example 2 Sodium methylate (30% aqueous solution) was added to polyoxypropylene triol with a molecular weight of io and ooo synthesized using the multimetal cyanide complex prepared in Example 1.
．． 2 wt% was added and the demethanol reaction was carried out at 80°C for 10
After 1 hour at Torr, ethylene oxide 200
After one reaction in which gr was introduced and the reaction was carried out at 100°C for 3 hours, the molar ratio of N to sodium methylate was 0.6 times.
axH*PxOt and 1.5 wt% water per polyol were added, and after stirring and mixing for 0.5 hours at a temperature of 110°C, 0.3 molar amount of Na was added to sodium methylate.
5H*PgOt powder was added, water was degassed under reduced pressure while stirring under the same temperature conditions as above, and crystals of pyrophosphate containing deactivated catalyst components were precipitated, and the polyether containing these precipitates was prepared as an example. Figure 1 shows the results of evaluating the filterability and properties of polyether treated by the method shown in 1.

It is shown in Table 1.

Comparative Example 1 Hll 10,000 polyether containing a deactivated catalyst synthesized under the same conditions as in Example 1 and treated with an aqueous potassium hydroxide solution was neutralized with various mineral acids in a stoichiometric or higher ratio to potassium hydroxide. After that, the precipitate was filtered under the same operating conditions as in Example 1.
Adsorption treatment with magnesium silicate was performed. The results are shown in Table 2.

Table Comparative Example 2 Polyether treated with sodium methylate under the same conditions as Example 2 was treated with NaJtPmOy at a molar ratio of 1.0 times that of sodium methylate per polyether.
．． Owt% of water was added, mixed for 1 hour at 120°C, degassed under reduced pressure while stirring under the same temperature conditions, and N
atH@P□0? and a reaction product of sodium methylate, and a complex containing a decomposition product of a multimetal cyanide complex is precipitated,
It was filtered.

The filtration rate was as low as 551/d·Hr, and some fine precipitates were filtered out, resulting in an opaque polyether. This polyether was treated with synthetic magnesium silicate under the same conditions as in Example 1, and Zn, Go,
As a result of measuring CPR, although Zn and Go were not detected, the CPR was as high as 12, and it was necessary to add 4.5% of synthetic magnesium silicate to reduce this value to ≦6.

[Effects of the Invention] As described above, the polyethers obtained by ring-opening a monoepoxide having 3 or more carbon atoms as an initiator using a multimetal cyanide complex as a catalyst can be used as a metal alkali or an alkali metal compound containing an organic compound. As a method for purifying polyethers, the polyether is treated with a treatment material selected from the above to deactivate the catalyst, and then, if necessary, ethylene oxide is subjected to a ring-opening reaction at the end of the polyether containing the deactivated catalyst.
- Monna M, H, P! 0. After treatment with a mixture of an acidic pyrophosphate appropriately selected from (M is Na or K) and water, the above-mentioned composite metal It has become clear that most of the decomposed products of the cyanide complex and the aforementioned processing agents can be separated from the polyethers, and that a cake with extremely good filterability is formed.

[Brief explanation of drawings]

FIG. 1 is a graph showing the relationship between the amount of water added and the filtration rate in Examples 1 and 2.

Claims (6)

[Claims] (1) Polyethers containing the above catalyst obtained by ring-opening a monoepoxide having 3 or more carbon atoms with an initiator in the presence of a multimetal cyanide complex catalyst are treated with an alkali metal or alkaline earth metal compound. Purification of polyethers, characterized by deactivating the catalyst, followed by treatment with acidic pyrophosphate in the presence of water, and then removing the deactivated catalyst component and treating agent component from the polyether. Method. (2) Acid pyrophosphate is M_xH_yP_2O_7(
2. The method according to claim 1, wherein M: alkali metal; x, y: each an integer of 1 or more; x+y=4). (3) Claim 1, wherein the amount of water in the treatment with acidic pyrophosphoric acid is 0.2 to 5 wt% based on the polyether.
The method described in section. (4) Polyethers containing the above catalyst obtained by ring-opening a monoepoxide having 3 or more carbon atoms with an initiator in the presence of a multimetal cyanide complex catalyst are treated with an alkali metal or alkaline earth metal compound. to deactivate the catalyst, then ring-opening reaction with ethylene oxide using polyethers as an initiator, then treatment with acidic pyrophosphate in the presence of water, and then treatment with the deactivated catalyst component from the polyethers. A method for purifying polyethers, characterized by removing agent components. (5) Acid pyrophosphate is M_xH_yP_2O_7(
M: alkali metal, x, y: each an integer of 1 or more x
5. The method according to claim 4, wherein +y=4). (6) The method according to claim 4, wherein the amount of water in the treatment with acidic pyrophosphoric acid is 0.2 to 5 wt% based on the polyether.