KR101209763B1 - A catalyst system for ring-opening polymerizations of epoxy compounds - Google Patents

Abstract

The present invention relates to an epoxy ring-opening polymerization system consisting of an active component of a metal complex, an organic complexing agent, and a phosphorus compound. The catalyst system of the present invention uses ethylene oxide (EO), propylene oxide (PO), and cyclohexane oxide ( When the ring-opening polymerization reaction of epoxy monomers such as CHO), the polymerization activation is very high, the polymerization induction time is short, the polyol produced is very low unsaturation and has the effect of significantly reducing the production of alcohol by-products.

Description

A catalyst system for ring-opening polymerizations of epoxy compounds

The present invention relates to a catalyst system for epoxy ring-opening polymerization reaction consisting of a metal complex compound, an organic complexing agent, and a phosphorus compound selected from the group consisting of double metal cyan salts.

Polyol is an industrially useful raw material such as used as an intermediate material for manufacturing polyurethane, etc., and is produced in large quantities. As a manufacturing method of a polyol, the method of ring-opening-polymerizing epoxy-type monomers, such as ethylene oxide (EO), a propylene oxide (PO), and a cyclohexane oxide (CHO), is known.

As the epoxy ring-opening polymerization catalyst, soluble basic metal hydroxides including potassium hydroxide (KOH) are generally used. However, polyols prepared under alkali metal hydroxide catalysts increase the content of monofunctional polyethers with terminal double bonds, the so-called monols, which are very disadvantageous in polyurethane production.

Recently, metal complex compounds such as double metal cyan salt (DMC) or multi metal cyan salt (MMC) have been known as catalysts for epoxy ring-opening polymerization. The use of the metal complex as a catalyst can not only relatively reduce the content of monool, but also increase the reaction rate of the addition of epoxy-based monomers. The polyols thus obtained can be used as high-quality polyurethane products such as coatings and elastomers. ), Sealants, foaming agents, adhesives and the like.

In a general method for preparing a metal complex catalyst, a metal salt and a metal cyan salt are reacted in an aqueous solution to prepare a precipitate of the metal complex. In the formation of the complexing compound, a complexing agent may be added separately. As such complexing agents, compounds of low molecular weight, for example, ethers, alcohols, ketones, esters, amides and urea compounds are used.

The preparation method of the metal complex catalyst for epoxy ring-opening polymerization which has been announced so far is as follows.

U.S. Patent Nos. 4,477,589, 3,821,505, and 5,158,922 disclose examples of using 'glyme, or dimethoxyethane' as a complexing agent in the preparation of double or multi-metal cyanide catalysts. The metal complex catalyst thus prepared has an activity of about 0.1 to 0.5 kg _-monomer / g _-metal / min using 100 ppm of catalyst based on the amount of epoxy monomers finally used at the epoxy ring-opening polymerization temperature of 105 ° C. Is reported.

U.S. Patent No. 5,780,584 reports that catalysts prepared using water soluble aliphatic alcohols such as tert -butyl alcohol as complexing agents have improved activity. However, when used in the epoxy ring-opening polymerization reaction, the polymerization induction time for activating the catalyst takes more than 4 hours.

A metal complex manufacturing process tert - 500 or more polyether-butyl alcohol complexing agent and a unit complex number average molecular weight as agent (U.S. Patent No. 5,482,908), or 500 or less polyether (U.S. Patent No. 5789626 No.) for each 5 to 80 Some examples have reported that the metal complex catalyst prepared by containing about% by weight increases the activity in the epoxy ring-opening polymerization reaction. The metal complex catalyst prepared using tert -butyl alcohol complexing agent and polyether polyol complexing agent is 2 kg in the amount of catalyst of 100 ppm based on the amount of the epoxy monomer finally used at 105 ° C of the epoxy ring-opening polymerization reaction. _-Monomer / g _- Can be polymerized at a rate of _metal / min or more, took 3 hours or more induction time.

The polymerization induction time is the time at which the catalyst is activated and no polymerization takes place at this time. Therefore, a long induction time has a disadvantage of low productivity. In addition, in the process of manufacturing double or multi-metal cyanide catalysts, main complexing agents and complexing agents are used to improve the catalytic activity. The synthesis process is cumbersome and takes a long time due to the use of the main complexing agent and the complexing agent. Not only does this deteriorate, but the organic complexing agent used is toxic and also has an adverse effect on the environment due to the excessive use of the catalyst during manufacture. In addition, the double or multi-metal cyanide catalyst prepared using the conventional organic complexing agent takes about 3 hours of induction time, and the epoxy ring-opening polymerization reaction is accompanied by exothermic reaction due to the high activity of the catalyst to increase the reaction temperature. Increasingly, there are risks to commercial use.

Therefore, in addition to the development of highly active metal complex catalysts, researches on additives to increase polymerization activity are also being actively conducted.

An object of the present invention is to provide a catalyst system for epoxy ring-opening polymerization reaction containing a metal complex as an active ingredient.

In order to achieve the object of the invention as described above, the present invention is a metal complex compound selected from the group consisting of ⅰ) a double metal cyan salt (DMC); Ii) an organic complexing agent selected from the group consisting of alcohols having 1 to 10 carbon atoms, glycols having a number average molecular weight of 500 to 5000, alkyl lactates having 1 to 6 carbon atoms, and mixtures thereof; And iii) phosphorus compounds; It characterized by the catalyst system for epoxy ring-opening polymerization reaction comprising a.

The epoxy ring-opening polymerization reaction using the catalyst system of the present invention produces a polyol having a very low unsaturation and has an effect of significantly reducing the production of primary alcohol by-products.

Epoxy ring-opening polymerization reaction using the catalyst system of the present invention has a high activity of the catalyst, the polymerization induction time is relatively short, there is an effect of shortening the reaction time.

1 is a graph showing the consumption of propylene oxide (PO) compound versus polymerization time according to the addition amount of triphenylphosphine (PPh ₃ ) as a phosphorus compound.

The present invention is characterized by a catalyst system for epoxy ring-opening polymerization. The catalyst system for epoxy ring-opening polymerization of the present invention includes a metal complex compound, an organic complexing agent, and a phosphorus compound.

Iii) The metal complex compound is a catalyst compound for ordinary epoxy ring-opening polymerization reaction as an active component constituting the catalyst system for epoxy ring-opening polymerization reaction of the present invention. Therefore, the present invention does not place any particular limitation on the selection of the metal complex, and all of the usual double metal cyanide salts (DMC) and the like which have been used in the epoxy ring-opening polymerization reaction can be applied.

As a representative example of such a metal complex compound, the water-soluble metal salt compound represented by the following formula (1) and the water-soluble metal cyan salt compound represented by the following formula (2) can be obtained by complexing reaction.

[Formula 1]

M (X) n

In Formula 1, M is Zn (II), Fe (II), Ni (II), Mn (II), Co (II), Sn (II), Pb (II), Fe (III), Mo (Ⅳ) ), Mo (VI), Al (II), V (V), V (IV), Sr (II), W (IV), W (VI), Cu (II), Cr (III), Preferably a 4 cycle metal element selected from the group consisting of Zn (II), Fe (II), Co (II), and Ni (II); X is an anion selected from the group consisting of halides, cyanide, hydroxides, carboxylates, nitrates, sulfates, carbonates, oxalates, isocyanates, thiocyanates; n is an integer of 1 to 3 to satisfy the valence of the metal element (M).

[Formula 2]

(Y) _a M'C (N) _b (A) _c

In Formula 2, M 'is Fe (II), Fe (III), Co (II), Co (III), Cr (II), Cr (III), Mn (II), Mn (III), Ir ( III), Ni (II), Rh (III), Ru (II), V (V), and V (IV), and are metal elements selected from the group consisting of Co (II), Co (III), A metal element selected from the group consisting of Fe (II), Fe (III), Cr (III), Ir (III), and Ni (II); Y is an alkali metal ion or alkaline earth metal ion; A is an anion selected from the group consisting of halides, cyanide, hydroxides, carboxylates, nitrates, sulfates, carbonates, oxalates, isocyanates, thiocyanates, and thioisocyanates; a and b are integers greater than 1, and the sum of the charges of a, b, and c satisfies the valence of the metal element (M ').

The water-soluble metal salt compound represented by Chemical Formula 1 is typically zinc chloride, zinc bromide, zinc acetate, acetone monoacetic acid (zinc acetonylacetonate), zinc benzoate, zinc nitrate, iron bromide (II), cobalt chloride (II), thiooxy Cobalt (II), nickel (II) formate, nickel (II) nitrate, and the like.

The water-soluble metal cyan salt compound represented by the formula (2) is typically potassium hexacyanocobalt (III), potassium hexacyanoferrate (II), potassium hexacyanoferrate (III), and hexacyanocobalt (III Calcium acid), lithium hexacyanoferrate (II) acid, and the like.

As a catalyst for epoxy ring-opening polymerization reaction applied to the catalyst system of the present invention, a representative metal complex compound of a double metal cyan salt (DMC) is prepared by reacting an aqueous zinc chloride solution with an aqueous solution of potassium hexacyanocobalt (III) acid. zinc chloride-zinc hexacyanocobalt (II) complexes represented by a).

Zn ₃ [Co (CN) ₆ ] ₂ ZnCl ₂ (a)

Ii) The organic complexing agent is a component which is added during or after complex formation to activate the complexing process for the preparation of the metal complex, which must be water soluble and well mixed with the metal complex. In the present invention, the organic complexing agent is selected from the group consisting of alcohols, glycols, alkyl lactates and mixtures thereof. The amount of the organic complexing agent is used in the range of 0.1 to 20 parts by weight, preferably in the range of 1 to 5 parts by weight based on 1 part by weight of the metal complex compound included as the active ingredient, and is used in an excessive amount. If the content of the organic complexing agent is too small, there is a problem that the activity of the catalyst is lowered, and if the content is too large, there may be a problem of drying and economical efficiency during the catalyst manufacturing process.

The alcohol used as the organic complexing agent in the present invention is an alcohol compound having 1 to 10 carbon atoms, specifically, water-soluble aliphatic alcohols such as ethanol, isopropanol, normal butanol, isobutanol, sec -butanol and tert -butanol. , Preferably tert -butanol. The glycols used as the organic complexing agent are glycols having a number average molecular weight in the range of 500 to 5000, and hyper-branched glycerols and copolymers thereof may be used. Specifically, polytetramethylene glycol (PTMEG) may be used. have. The lactate used as the organic complexing agent is an alkyl lactate compound having 1 to 6 carbon atoms, and methyl lactate, ethyl lactate, propyl lactate, isopropyl lactate, butyl lactate and the like can be used.

I) Phosphorus-based compounds significantly shorten the induction time for epoxy ring-opening polymerization, synthesize high molecular weight polyols with low unsaturation, and significantly reduce the production of by-product primary alcohols during ring-opening polymerization. In the prior art, a catalyst system including a double metal cyanide salt (DMC), an organic complexing agent, and a polyether additive took 3 hours or more to induce a polymerization time, whereas the catalyst complex compound proposed by the present invention. The catalyst system including the organic complexing agent, and the phosphorus compound additive has an advantage that the polymerization induction time is greatly shortened to 70 minutes or less.

The phosphorus compound included in the catalyst system of the present invention is selected from the group consisting of triphenylphosphine (PPh ₃ ), tricyclohexylphosphine (PCy ₃ ), and hexaphenyldiphosphazenium chloride (PPNCl).

The phosphorus compound is used in the range of 0.1 to 20 parts by weight based on 1 part by weight of the metal complex compound, preferably in the range of 0.3 to 15 parts by weight, and particularly preferably in the range of 3 to 10 parts by weight. When the content of the phosphorus compound is less than the above range, it is not possible to obtain an effect of shortening the polymerization induction time as an addition effect thereof, and when excessively used, the polymerization induction time may be increased.

Epoxy ring-opening polymerization method will be described in detail using a catalyst system comprising (i) a metal complex compound described above, ii) an organic complexing agent, and (iv) a phosphorus compound.

Epoxy ring-opening polymerization method using the catalyst system of the present invention,

1) a water soluble metal salt compound; Water-soluble metal cyanide compounds; And an aqueous solution containing an organic complexing agent selected from the group consisting of alcohols having 1 to 10 organic carbon atoms, glycols having a number average molecular weight of 500 to 5000 carbon atoms, alkyl lactates having 1 to 6 carbon atoms, and mixtures thereof. Stirring to obtain a catalyst slurry,

2) separating the solids from the slurry,

3) The separated solid is washed with an aqueous solution containing an organic complexing agent selected from the group consisting of alcohols having 1 to 10 carbon atoms, glycols having a number average molecular weight of 500 to 5000, alkyl lactates having 1 to 6 carbon atoms, and mixtures thereof. Obtaining a catalyst, and

4) mixing the solid catalyst, the phosphorus compound, and the epoxide compound and epoxy ring-opening polymerization at a temperature of 100 ° C. to 150 ° C .; .

There is no particular limitation on the concentration of the metal compounds, organic complexing agents, phosphorus compounds used in the preparation of the catalyst and the order of mixing.

First, in the present invention, a catalyst slurry is obtained by mixing a metal complex aqueous solution and an organic complexing agent aqueous solution. To obtain a solid catalyst from the catalyst slurry, filtration or centrifugation is carried out. The filtration or centrifugation described above may remove unreacted metal complexes and organic complexing agents present in the catalyst system of the present invention. According to the experimental results of the present inventors, the catalyst system of the present invention contains a metal complex and an organic complexing agent in an amount of less than 5 ppm, respectively, it is possible to obtain a high purity catalyst system by performing a filtration or centrifugation process for producing a solid catalyst. In the catalyst system of the present invention, organic complexing agents or metal complexes used in excess may remain as impurities, but the presence of these excess compounds does not particularly affect the purity of the product in the epoxy ring-opening polymerization reaction. In the case of using potassium hydroxide (KOH) as a conventional catalyst, the purification process is included as an essential process before being applied to the ring-opening polymerization reaction, but the catalyst system of the present invention does not require a separate purification process, and thus has great economic benefits.

Then, the solid separated from the slurry is washed with an aqueous solution of a complexing agent at a concentration of 40 to 70% by weight to obtain a solid catalyst. By-products such as potassium chloride (KCl) may be produced during the complexation reaction, and by-products such as potassium chloride (KCl) may cause inactivation of the catalyst. The washing process with the above complexing agent aqueous solution may be repeated one or several times, and more preferably, it is sufficiently washed to completely remove the by-products. It is preferable to use only the complexing agent in the last washing process without using filtered water. When the washing process of the solid catalyst is completed, a drying process is performed. Drying is carried out in a vacuum of 10 to 50 Torr and at a temperature of 40 to 90 ° C., and the drying conditions are maintained until the weight of the solid catalyst is kept constant.

Then, the obtained solid catalyst, a phosphorus compound and an epoxide compound are mixed and polymerized. When the polymerization temperature is maintained at 100 ℃ to 150 ℃, the pressure is preferably maintained within 5 kg _f / cm ² for stability. The polyol obtained by the epoxy ring-opening polymerization of the present invention had a high number average molecular weight (Mn) in the range of 5,000 to 100,000, a very low unsaturation of less than 0.005 meq / g, and a low polymerization induction time of 67 minutes. In addition, the decrease in the degree of unsaturation could significantly reduce the yield of primary alcohol by-products.

The present invention as described above will be described in more detail based on the following examples, but the present invention is not limited by these examples.

[Example] Epoxy ring-opening polymerization reaction using a metal complex catalyst system

1) Preparation of Solid Catalyst

Solution 1 was prepared by mixing 30 g of zinc chloride, 69 mL of distilled water, and 115.5 mL of tert -butyl alcohol in a beaker. Another solution was prepared by dissolving 3.15 g of potassium hexacyanocobaltate in 42 mL of distilled water in another beaker. Another solution was prepared by mixing 3.5 g of polytetramethylene glycol (PTMEG, number average molecular weight 1800), 20 mL of tert -butyl alcohol, and 20 mL of distilled water in another beaker. Solution 2 was added dropwise to Solution 1 at 50 ° C. for 1 hour while mixing using a mechanical stirrer, then Solution 3 was added and reacted for 3 minutes. 46 mL of distilled water and 104 mL of tert -butyl alcohol were mixed in the catalyst slurry thus obtained, and reacted at 50 ° C. for 1 hour while mixing using a mechanical stirrer. After the reaction for 1 hour, 0.85 g of polytetramethylene glycol (PTMEG) was added to the reactor, followed by stirring for 3 minutes. Solids were separated using a high speed centrifuge. 77.75 mL of tert -butyl alcohol was mixed with the solid content thus separated and reacted at 50 ° C. for 1 hour while mixing using a mechanical stirrer. After the reaction for 1 hour, 0.45 g of PTMEG was added to the reactor, followed by stirring for 3 minutes. The obtained solid catalyst was removed by centrifugation three times using 100 mL of distilled water and 50 mL of tert -butyl alcohol. The solid catalyst obtained through the above manufacturing process was dried to a constant weight at 60 ° C. and 30 in. Hg vacuum to prepare a solid catalyst (DMC-1).

2) epoxy ring-opening polymerization

In this ring-opening polymerization reaction, the effect on the polymerization rate, activation induction time, unsaturation was confirmed while changing the amount of the phosphorus compound added to the solid catalyst prepared above.

Specifically, 70 g of polypropylene glycol (PPG) having a molecular weight of 400, 0.05 g of the solid catalyst (DMC-1) prepared above, and 0.075 g of triphenylphosphine (PPh ₃ ) were added to the 1 L high pressure reactor. . The mixture was raised to 115 ° C. with good stirring, and then kept in vacuum for about 2 hours to remove moisture remaining in the mixture. 15 g of propylene oxide (PO) was injected into the reactor. At this time the pressure of the reactor was increased from vacuum to 4 psig. After the polymerization induction time, the pressure drop appeared in the reactor, it can be seen from the activity of the catalyst. When the activity of the catalyst appeared 400 g of propylene oxide (PO) was continuously injected into the reactor to maintain a pressure of about 10 psig.

The activity of the catalyst was measured at the steepest point in the graph of propylene oxide (PO) consumption versus time. After injection of propylene oxide (PO) was maintained at 115 ℃ until the pressure was kept constant, that is, the polymerization of propylene oxide (PO) is complete. Vacuum was maintained at 60-80 ° C. for 30 minutes to remove unreacted propylene oxide (PO) in the reactor. The produced polymer was recovered by cooling.

Table 1 and the accompanying drawings in Figure 1 summarized the effects on the polymerization rate, activation induction time, unsaturation while varying the content of the phosphorus compound based on the amount of DMC catalyst used.

division Catalyst system Molecular Weight
(M _n ) Molecular Weight
Distribution
(PDI) Induction time
(min) Unsaturation
(meq / g) Solid catalyst ¹⁾ Phosphorus compound
(Weight part ²⁾ ) Example 1 DMC-1 PPh ₃ (1.5) 5500 1.13 178 0.00452 Example 2 DMC-1 PPh ₃ (3.0) 5200 1.12 104 ** ³⁾ Example 3 DMC-1 PPh ₃ (6.0) 6700 1.12 67 ** ³⁾ Example 4 DMC-1 PPh ₃ (10.0) 6000 1.10 74 ** ³⁾ Example 5 DMC-1 PPh ₃ (13.0) 5600 1.13 167 0.00289 Comparative Example 1 DMC-1 - 5700 1.13 207 0.00460 Comparative Example 2 KOH 2000 0.02608 Comparative Example 3 KOH 3000 0.03591 1) Solid catalyst: Zn ₃ [Co (CN) ₆ ] ₂ ZnCl ₂ Solid catalyst prepared in a representative example using a metal complex and an organic complexing agent t-BuOH, PTMEG
2) Phosphorus compound: The amount of phosphorus compound added based on 1 part by weight of DMC catalyst (DMC catalyst amount: 0.05g)
3) **: Indicates that the unsaturation level is too low to be measured (measured by ASTM D2847 method).

According to the results of Table 1 and Figure 1, the addition of the phosphorus-based compound significantly shortened the polymerization induction time, it was possible to prepare a high molecular weight polyol, the degree of unsaturation of the prepared polymer was very low and because of this the primary alcohol part The yield of the product could be significantly reduced.

Claims (9)

Iii) a metal complex selected from the group consisting of double metal cyan salts (DMC);
Ii) an organic complexing agent selected from the group consisting of alcohols having 1 to 10 carbon atoms, glycols having a number average molecular weight of 500 to 5000, alkyl lactates having 1 to 6 carbon atoms, and mixtures thereof; And
Iii) a phosphorous compound selected from the group consisting of triphenylphosphine (PPh ₃ ), tricyclohexylphosphine (PCy ₃ ), and hexaphenyldiphosphazenium chloride (PPNCl);
Epoxy ring-opening polymerization catalyst system comprising a.
The catalyst system for epoxy ring-opening polymerization according to claim 1, wherein the double metal cyanide salt (DMC) is zinc chloride-zinc hexacyanocobalt (II) acid represented by the following formula (a).
(A)
Zn ₃ [Co (CN) ₆ ] ₂ ZnCl ₂
The catalyst system for epoxy ring-opening polymerization of claim 1, wherein the organic complexing agent is included in an amount of 0.1 to 20 parts by weight based on 1 part by weight of the metal complex compound.
The catalyst system for epoxy ring-opening polymerization according to claim 1, wherein the alcohol as the organic complexing agent is selected from the group consisting of ethanol, isopropanol, normal butanol, isobutanol, sec-butanol, and tert-butanol.
The catalyst system for epoxy ring-opening polymerization according to claim 1, wherein the glycol as the organic complexing agent is polytetramethylene glycol (PTMEG) having a number average molecular weight in the range of 500 to 5000.
The catalyst system for epoxy ring-opening polymerization according to claim 1, wherein the alkyl lactate as the organic complexing agent is selected from the group consisting of methyl lactate, ethyl lactate, propyl lactate, and isopropyl lactate.
delete The catalyst system for epoxy ring-opening polymerization of claim 1, wherein the phosphorus compound is included in an amount of 0.1 to 20 parts by weight based on 1 part by weight of the metal complex compound.
1) a water soluble metal salt compound; Water-soluble metal cyanide compounds; And an aqueous solution containing an organic complexing agent selected from the group consisting of alcohols having 1 to 10 organic carbon atoms, glycols having a number average molecular weight of 500 to 5000 carbon atoms, alkyl lactates having 1 to 6 carbon atoms, and mixtures thereof. Stirring process,
2) separating the solids from the reaction solution,
3) The separated solid is washed with an aqueous solution containing an organic complexing agent selected from the group consisting of alcohols having 1 to 10 carbon atoms, glycols having a number average molecular weight of 500 to 5000, alkyl lactates having 1 to 6 carbon atoms, and mixtures thereof. Obtaining a catalyst, and
4) the solid catalyst; Phosphorus compounds selected from the group consisting of triphenylphosphine (PPh ₃ ), tricyclohexylphosphine (PCy ₃ ), and hexaphenyldiphosphazenium chloride (PPNCl); And the process of mixing the epoxide compound, the epoxy ring-opening polymerization reaction at a temperature of 100 ℃ to 150 ℃,
Epoxy ring-opening polymerization method comprising a.

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