KR20090090154A - Method for recovering catalysts from a copolymerization process - Google Patents

Abstract

A method for recovering catalysts from copolymers is provided to lower costs of a catalyst by reusing the catalyst used for the manufacture of the copolymers, and to prepare the copolymers with high purity. A method for recovering catalysts from the solution in which copolymer and catalyst are dissolved comprises the steps of: contacting the solution in which a copolymer and a catalyst are dissolved, with a solid-phase inorganic material, a polymer material or their mixture which are not dissolved in the solution, forming complexes of the solid-phase inorganic material or polymer material with the catalyst, and separating the copolymer; and treating the complexes of the solid-phase inorganic material or polymer material with the catalyst with acid or metal salt of non-reactive anions in a medium which cannot dissolve the solid-phase inorganic material or polymer material, and dissolving the catalyst in the medium and collecting separately the catalyst.

Description

METHODS FOR RECOVERING CATALYSTS FROM A COPOLYMERIZATION PROCESS}

The present invention relates to a method for separating and recovering a catalyst from a solution in which a copolymer and a catalyst are dissolved after performing a polymerization reaction using a catalyst.

Method for preparing a polycarbonate by copolymerizing epoxide and carbon dioxide using a complex containing an onium salt as a catalyst has been filed in the Republic of Korea Patent Application 10-2007-0043417 by the same inventor (application date: 2007.05.04, Name of the Invention: A complex compound having two components in one molecule and a method for producing polycarbonate by copolymerization of carbon dioxide and epoxide using the same as a catalyst). When a complex compound containing an onium salt is used as a catalyst, the catalyst is maintained in the polymerization medium in which the epoxide and carbon dioxide are copolymerized, regardless of their concentration, so that the catalyst has a high polymerization activity at a high monomer / catalyst condition and at high temperature. Since the selectivity is reduced, the amount of the catalyst used can be reduced, and there is an economic benefit, and a high molecular weight polycarbonate can be provided, which is advantageous in that it is introduced into a commercial process.

The present invention relates to a method of separating and recovering a catalyst from a mixed solution of a copolymer and a catalyst obtained when a polycarbonate is prepared by copolymerizing epoxide and carbon dioxide using a complex containing an onium salt as a catalyst. .

The biggest disadvantage of homogeneous catalysts is that they are not easy to recover and reuse. In order to overcome the shortcomings of the homogeneous catalyst, efforts have been made to make the catalyst insoluble in a solvent by attaching the catalyst to an inorganic material support such as silica or a polymer support. In this case, since the catalyst is placed in the pores of the support, it is difficult to smoothly access the reaction material, and thus many reactions have been found in which the reaction rate or selectivity is lower than that of the homogeneous catalyst.

Another method of recovering and reusing a catalyst is to prepare a catalyst dissolved in water, a catalyst dissolved in a fluorine-containing solvent, or a catalyst dissolved in an ionic liquid and reacted in a medium or a mixed medium with an organic material. Methods of separating and recycling the catalyst from the product using a property in which organic matter does not dissolve in water, a fluorine-containing solvent, or an ionic liquid have been developed and used in some commercial applications.

The simplest method is to separate and recover the catalyst from the product and reuse it by various compound purification methods such as distillation, vacuum distillation, precipitation and chromatography after the reaction.

When preparing a polymer using a metal compound, recovering or removing the catalyst from the polymer material is more difficult than recovering or removing the catalyst after preparing the monomolecular organic material. If the metal itself is expensive and the ligand is not simple, the synthesis of the ligand is expensive, and most of the metal compounds are expensive to manufacture, and thus, the cost of the resin increases if the product is not recovered and reused. In addition to these catalyst costs, if a polymer is prepared using a metal compound catalyst, if the catalyst is not completely removed, most of the metal compounds have a toxicity and cause problems in application development. In addition, most of the metal compounds have a color, and if the transition metal compound is not completely removed, the copolymer becomes colored and causes a problem. The presence of trace amounts of metal compounds can be fatal for use as electronic materials. For this reason, many methods have been studied in academia for producing polymers using metals, but there are not many commercially available examples.

Representative polymerization methods using metal as a catalyst are the production of polyethylene and polypropylene using Ziegler-Natta catalysts. Currently, Ziegler-Natta catalysts are highly active, producing resins without recovering or removing the catalyst, but when the initial activity was not high, there was a deashing process to remove the catalyst. In a process requiring initial deliming, the Ziegler-Natta catalyst was quite unstable and was not expensive to manufacture the catalyst, so it was recovered and removed without reuse.

The catalyst showing the highest activity among the copolymerization catalysts of carbon dioxide / epoxide is a complex compound comprising an onium salt provided in Korean Patent Application No. 10-2007-0043417 (filed date: 2007.05.04) of the present inventors. However, its activity is significantly lower, about 1/100 of that of Ziegler-Natta catalysts. The highest activity level of the presently implemented catalyst is that the polymer becomes pale red unless it is polymerized to about 1.5 Kg-polymer / g-catalyst level and the catalyst is not recovered or removed. Since the catalyst is manufactured through the catalyst, if the catalyst is not recovered and reused, the cost of the catalyst is high, which impedes commercialization.

It is an object of the present invention to provide a method for recovering and reusing a catalyst from a mixed solution of a copolymer and a catalyst obtained after preparing a copolymer by using a complex containing an onium salt as a catalyst.

In order to achieve the above object, the present invention provides a method for separating and recovering a catalyst from a copolymer from a solution in which a copolymer and a catalyst are dissolved by the following steps:

Separating the copolymer by contacting the solution in which the copolymer and the catalyst are dissolved with a solid inorganic material, a high molecular material or a mixture thereof, which does not dissolve in the solution to form a complex of the solid inorganic material or the polymer material and the catalyst ; And

In a medium in which the solid inorganic material or the polymer material cannot be dissolved, the complex of the solid inorganic material or the polymer material and the catalyst is treated with a metal salt of an acid or a non-reactive anion so that the catalyst is dissolved out of the medium. Separating and recovering the catalyst.

The method according to the present invention can reduce the cost of the catalyst by separating and recovering and reusing the catalyst used in the preparation of the copolymer to implement economics in the production of the copolymer, and by removing the catalyst which is a metal compound from the copolymer, It is possible to prepare the copolymer to expand the range of use of the copolymer.

In one embodiment of the present invention, the contact between the solution in which the copolymer and the catalyst are dissolved and the solid inorganic material, the polymer material, or a mixture thereof is used to dissolve the copolymer and the catalyst in the solid inorganic material, the polymer material or a mixture thereof. This is done by adding to the solution followed by filtration or by passing the solution in which the copolymer and catalyst are dissolved through a column packed with a solid inorganic material, a polymeric material or a mixture thereof.

In another embodiment of the present invention, the solid phase inorganic material is surface modified or unmodified silica or alumina, and the solid phase polymeric material is a polymeric material having a functional group capable of deprotonation reaction by an alkoxy anion.

In another embodiment of the present invention, the functional group from which the deprotonation reaction can take place with an alkoxy anion is a sulfonic acid group, a carboxylic acid group, a phenol group or an alcohol group.

In another embodiment of the present invention, the catalyst contained in the solution in which the copolymer and the catalyst are dissolved comprises as onium salt at least one of the functional groups represented by the following formulas (1), (2) and (3) and the central metal has a Lewis acid group. to be:

Where

Z is nitrogen or phosphorus;

X is halogen; Aryloxy of 6 to 20 carbon atoms, carboxyl of 1 to 20 carbon atoms, alkoxy of 1 to 20 carbon atoms, alkylsulfonyl of 1 to 20 carbon atoms, with or without halogen, nitrogen, oxygen, silicon, sulfur and phosphorus Earth, or amido having 1 to 20 carbon atoms, wherein X may be coordinated with a central metal having Lewis acid groups;

R ¹¹ , R ¹² , R ¹³ , R ²¹ , R ²² , R ²³ , R ²⁴ and R ²⁵ are each independently or simultaneously hydrogen; C1-C20 alkyl, C2-C20 alkenyl, C7-C20 alkylaryl, or C7-C20 aryl, with or without halogen, nitrogen, oxygen, silicon, sulfur and phosphorus Alkyl radicals; Or a metalloid radical of a Group 14 metal substituted with hydrocarbyl, wherein two of R ¹¹ , R ¹² and R ¹³ or two of R ²¹ , R ²² , R ²³ , R ²⁴ and R ²⁵ are connected to each other to form a ring Can form;

R ³¹ , R ³² and R ³³ are each independently or simultaneously hydrogen; C1-C20 alkyl, C2-C20 alkenyl, C7-C20 alkylaryl, or C7-C20 aryl, with or without halogen, nitrogen, oxygen, silicon, sulfur and phosphorus Alkyl radicals; Or a metalloid radical of a Group 14 metal substituted with hydrocarbyl, wherein two of R ³¹ , R ³² and R ³³ can be linked to each other to form a ring;

X 'is oxygen, sulfur or NR, wherein R is hydrogen; alkyl having 1 to 20 carbon atoms with or without at least one of halogen, nitrogen, oxygen, silicon, sulfur and phosphorus, alkenyl having 2 to 20 carbon atoms, Alkylaryl having 7 to 20 carbon atoms or arylalkyl radical having 7 to 20 carbon atoms.

In another embodiment of the invention, the complex comprising at least one of the functional groups of Formula 1, Formula 2 and Formula 3, wherein the central metal has a Lewis acid group, has a structure of Formula 4:

Where

M is a transition metal or a typical metal;

X 'is a ligand of neutral or monovalent anion;

A is oxygen or sulfur;

Q is alkyl having 1 to 20 carbon atoms, cycloalkyl diradical having 3 to 20 carbon atoms, aryl diradical having 6 to 30 carbon atoms, or containing at least one of halogen, nitrogen, oxygen, silicon, sulfur and phosphorus Dioxy radical of 1 to 20;

R ¹ to Each R ¹⁰ is independently or simultaneously hydrogen; C1-C20 alkyl, C2-C20 alkenyl, C7-C20 alkylaryl, or C7-C20 aryl, with or without halogen, nitrogen, oxygen, silicon, sulfur and phosphorus Alkyl radicals; Or a metalloid radical of a Group 14 metal substituted with hydrocarbyl, wherein R ¹ to R ¹⁰ Two may be linked to each other to form a ring;

R ¹ to At least one or more of R ¹⁰ includes at least one of the functional groups of the formulas (1), (2) and (3), wherein X in formulas (1), (2) and (3) may be coordinated to the central metal having Lewis acid group.

Further, preferably, the complex according to the present invention has the structure of formula (5):

Where

M 'is cobalt;

X ″ is aryloxy having 6 to 20 carbon atoms, unsubstituted or substituted with a halogen, nitro group, or carboxy having 1 to 20 carbon atoms, unsubstituted or substituted with halogen;

A 'is oxygen;

Q 'is trans-1,2-cyclohexylene, ethylene or substituted ethylene;

R ' ¹ , R' ² , R ' ⁴ , R' ⁶ , R ' ⁷ and R' ⁹ are hydrogen;

R ' ⁵ and R' ¹⁰ are tert-butyl, methyl or isopropyl,

At least one of R ' ³ and R' ⁸ is-[YR ⁴¹ _3-m {(CR ⁴² R ⁴³ ) _n NR ⁴⁴ R ⁴⁵ R ⁴⁶ } _m ] X " _m or-[PR ⁵¹ R ⁵² = N = PR ⁵³ R ⁵⁴ R ⁵⁵ ] X ";

Y is carbon or silicon;

R ⁴¹ , R ⁴² , R ⁴³ , R ⁴⁴ , R ⁴⁵ , R ⁴⁶ , R ⁵¹ , R ⁵² , R ⁵³ , R ⁵⁴ and Each R ⁵⁵ is independently or simultaneously hydrogen; C1-C20 alkyl, C2-C20 alkenyl, C7-C20 alkylaryl or C7-C20 arylalkyl, with or without halogen, nitrogen, oxygen, silicon, sulfur and phosphorus Radicals; Or a metalloid radical of Group 14 metal substituted with hydrocarbyl, R ⁴⁴ , 2 of R ⁴⁵ and R ⁴⁶ or R ⁵¹ , R ⁵² , R ⁵³ , R ⁵⁴ and Two of R ⁵⁵ may be linked to one another to form a ring;

m is an integer of 1 to 3;

n is an integer of 1 to 20.

Further, more preferably, the complex according to the present invention has a structure of one of the following formulas 6 to 10:

Where

M is cobalt or chromium;

R ⁶¹ and R ⁶² are each independently or simultaneously hydrogen, methyl, isopropyl or tert-butyl;

X is halogen; Aryloxy of 6 to 20 carbon atoms, carboxyl of 1 to 20 carbon atoms, alkoxy of 1 to 20 carbon atoms, alkylsulfonyl of 1 to 20 carbon atoms, with or without halogen, nitrogen, oxygen, silicon, sulfur and phosphorus Earth, or amido having 1 to 20 carbon atoms, wherein X may be coordinated with a central metal having Lewis acid groups;

n is an integer of 1 to 20.

According to the present invention, "a solution in which a copolymer and a catalyst are dissolved" includes an alkylene oxide having 2 to 20 carbon atoms which may be substituted or unsubstituted with halogen or alkoxy using the catalyst; Cycloalkene oxides having 4 to 20 carbon atoms, optionally substituted with halogen or alkoxy; And it is prepared by copolymerizing epoxide and carbon dioxide selected from the group consisting of styrene oxide of 8 to 20 carbon atoms, optionally substituted with halogen, alkoxy or alkyl.

Specific examples of epoxides that can be used for copolymerization include ethylene oxide, propylene oxide, butene oxide, pentene oxide, hexene oxide, octene oxide, decene oxide, dodecene oxide, tetradecene oxide, hexadecene oxide, octadecene oxide, butadiene Monoxide, 1,2-epoxy-7-octene, epifluorohydrin, epichlorohydrin, epibromohydrin, isopropyl glycidyl ether, butyl glycidyl ether, t-butyl glycidyl ether , 2-ethylhexyl glycidyl ether, allyl glycidyl ether, cyclopentene oxide, cyclohexene oxide, cyclooctene oxide, cyclododecene oxide, alpha-pinene oxide, 2,3-epoxynorbornene, limonene oxide, Dieldrin, 2,3-epoxypropylbenzene, styrene oxide, phenylpropylene oxide, stilbene oxy De, chlorostilbene oxide, dichlorostilbene oxide, 1,2-epoxy-3-phenoxypropane, benzyloxymethyl oxirane, glycidyl-methylphenyl ether, chlorophenyl-2,3-epoxypropyl ether, epoxypropyl Methoxyphenyl ether, biphenyl glycidyl ether, glycidyl naphthyl ether and the like.

Epoxides can be used in polymerizations using organic solvents as reaction media, which include aliphatic hydrocarbons such as pentane, octane, decane and cyclohexane, aromatic hydrocarbons such as benzene, toluene and xylene, chloromethane, methylene chloride, chloroform , Carbon tetrachloride, 1,1-dichloroethane, 1,2-dichloroethane, ethylchloride, trichloroethane, 1-chloropropane, 2-chloropropane, 1-chlorobutane, 2-chlorobutane, 1-chloro- It can be used alone or in combination of two or more of halogenated hydrocarbons such as 2-methylpropane, chlorobenzene and bromobenzene. More preferably, bulk polymerization can be carried out using itself as a solvent.

The volume ratio of solvent used to the epoxide, ie the solvent: epoxide volume ratio, is from 0: 100 to 99: 1, preferably from 0: 100 to 90:10.

The molar ratio of epoxide to catalyst, ie epoxide: catalyst molar ratio, can be used at 1,000: 1 to 500,000: 1, preferably at 10,000: 1 to 100,000: 1.

The pressure of carbon dioxide can be up to 100 atm, preferably at 2 to 50 atm.

Polymerization temperature is possible from 20 degreeC to 120 degreeC, Preferably 50 degreeC-100 degreeC is suitable.

As a method of polymerizing a polycarbonate, there exist a batch polymerization method, a semi-batch polymerization method, or a continuous polymerization method. In the case of using a batch or semi-batch polymerization method, the reaction time can be 1 to 24 hours, preferably 1.5 to 6 hours. In the case of using the continuous polymerization method, the average residence time of the catalyst is also preferably set to 1 to 24 hours.

"Solution in which a copolymer and a catalyst are dissolved" is a solution obtained in a step in which carbon dioxide and epoxide which remain unreacted after performing the polymerization reaction described above, a solution obtained by removing only carbon dioxide, or a polymerization reaction It may be a solution obtained by removing all of carbon dioxide and epoxide and then re-adding another solvent for post-treatment. Methylene chloride, THF, etc. are preferable as a solvent that can be used for the workup.

The solid inorganic material which is not dissolved in the solution in which the copolymer and the catalyst are dissolved is silica or alumina which is surface-modified or not surface-modified, preferably silica.

Solid polymer material which is insoluble in a solution in which a copolymer and a catalyst are dissolved serves as a support having a "functional group capable of causing a deprotonation reaction by an alkoxy anion". Representative examples of "functional groups in which deprotonation can occur by alkoxy anions" include sulfonic acid groups, carboxylic acid groups, phenol groups or alcohol groups. The solid polymer is preferably crosslinked with a number average molecular weight of 500 to 10,000,000, but is not dissolved in a solution containing a copolymer and a catalyst even if not crosslinked.

More specific examples of "a solid polymer material having a functional group capable of deprotonation reaction by an alkoxy anion" include a copolymer including a monomer such as the following Chemical Formulas 11 to 15 in the polymer chain, or a homopolymer composed only of such monomers. (homopolymer). The polymeric material serving as this support may be uncrosslinked as long as it does not dissolve in the above-described solution, but is preferably crosslinked appropriately to reduce solubility:

In the process according to the invention, the solid inorganic material, the polymeric material or a mixture thereof is added to the solution in which the copolymer and the catalyst are dissolved and then filtered, or the solution in which the copolymer and the catalyst are dissolved is dissolved in the solid inorganic material, The copolymer can be separated by passing it through a column packed with a polymeric material or mixture thereof to form a complex of the solid inorganic material or polymeric material with a catalyst.

In this case, the complex containing at least one of the functional groups of Formula 1, Formula 2, and Formula 3 and having a Lewis acid group as the central metal is a compound of a complex salt composed of a cation and an anion. On the other hand, the copolymer can pass through the column so that the copolymer and the catalyst can be separated.

When copolymerizing epoxide and carbon dioxide using the complex as a catalyst, it is generally accepted that the reaction is initiated by nucleophilic attack of an activated epoxide coordinated with an anion of an onium salt on a central metal having a Lewis acid group. . The alkoxy anion formed upon nucleophilic attack reacts with carbon dioxide to become a carbonate anion, which is then coordinated to the central metal to nucleophile attack the activated epoxide to form a carbonate anion, and the reaction is repeated to form a polymer chain. . In this case, after the polymerization reaction, some or all of the anions of the onium salts contained in the catalyst are converted to carbonate anions or alkoxide anions containing the polymer chain. Removing carbon dioxide after the polymerization reaction converts the carbonate anion to an alkoxide anion.

When the solution in which the catalyst and the copolymer are dissolved after polymerization is brought into contact with the "polymer material having a functional group capable of deprotonation reaction by an alkoxy anion", the "functional group capable of deprotonation reaction" of the high molecular material is obtained. An acid-base reaction with an alkoxide anion containing a polymer chain, which is present as an anion of a salt, causes the polymer chain to be protonated, neutralized, dissolved in a solution, and a catalyst containing a polymer material and an onium salt forms a complex. This complex can be separated by filtration from the copolymer for reasons of insolubility. Scheme 1 below specifically illustrates the reaction of the catalyst removal process from the copolymers described above.

It is not necessary to remove all of the carbon dioxide before contacting the solution with the support. If the carbon dioxide is not removed, there is a high possibility that the Y anion is present as a carbonate anion in Scheme 1. The carbonate anion may react with the protons present in the support to release carbon dioxide, thereby achieving the same purpose.

The catalyst can be recovered and reused from the catalyst-inorganic material composite or catalyst-polymer composite separated and recovered by filtration. The catalyst-inorganic material complex or catalyst-polymer complex is not soluble in conventional solvents. However, when a metal salt of an acid or a non-reactive anion is treated to a recovered catalyst-inorganic material complex or catalyst-polymer complex in a medium that does not dissolve an inorganic material or a polymer material, the catalyst may be reacted by an acid-base reaction or a salt metathesis reaction. Is dissolved in the medium and filtered to separate the inorganic material or the polymer and the catalyst, and the inorganic material or the polymer and the catalyst can be recovered and reused. At this time, the PKa value of the treated acid should have a value less than or equal to the PKa value of the anion formed on the support. The preferred acid to be treated is advantageous in that it must be selected so that the counterbase of the acid exhibits excellent performance in realizing the activity in the polymerization reaction. Preferred as such acids are HCl and 2,4-dinitrophenol. Cl anions and 2,4-dinitrophenolate anions are known to exhibit high activity and high selectivity during polymerization. Preferred as salts of non-reactive anions are MBF ₄ or MClO ₄ , wherein M is Li, Na or K. When the salt of the non-reactive anion is treated, the compound containing the non-reactive anion is dissolved. This non-reactive anion can be converted by salt metathesis into a Cl anion and a 2,4-dinitrophenolate anion showing high activity and high selectivity. The process of recovering the catalyst is carried out under a suitable solvent in which the catalyst is dissolved and the inorganic or polymeric material is not dissolved. Preferred such solvents are methylene chloride, ethanol or methanol. Schemes 2 and 3 below specifically illustrate a scheme for recovering a catalyst from a complex of a polymer material and a catalyst or a complex of an inorganic material and a catalyst.

The present invention will be described in more detail with reference to the following examples. However, the following examples are only for illustrating the present invention and are not intended to limit the scope of the present invention.

Example

Example 1 Copolymer Preparation Process Including a Separation and Recovery Method of Catalysts Using a 50 mL Reactor

First step: copolymerization of carbon dioxide / propylene oxide

As a representative catalyst of the present invention, the compound of Formula 10, wherein X is 2,4-dinitrophenolate, R ⁶¹ and R ⁶² are methyl, and n is 3. The catalyst (7.0 mg) was dissolved in propylene oxide (9.0 g, 150 mmol) and then placed in a 50 mL bomb reactor to assemble the reactor. The reactor was immersed in an oil bath previously adjusted to 80 ° C. and stirred for about 15 minutes so that the reactor temperature was in equilibrium with the bath temperature. The reaction proceeded for 30 minutes while injecting carbon dioxide at a pressure of 20 bar. After removing the carbon dioxide gas, the reactor was opened to obtain a pale red highly viscous solution. The resulting solution was highly viscous, unable to stir and not easily filtered, so that 20 g of propylene oxide was further added to obtain a low-viscosity solution capable of stirring and filtration. For comparison, some polymers were taken from the untreated copolymer solution and processed to analyze the amount of cobalt contained in the copolymer with an ICP-mass spectrometer (Table 1). In addition, after removing all solvents, the copolymer was dissolved in 20 mL of methylene chloride, and the absorbance was measured by an ultraviolet-visible spectrometer (UV-Visible Spectrometer) (FIG. 2). In the copolymer solution thus prepared, propylene oxide was removed under vacuum reduced pressure to obtain 4.1 g of copolymer. This corresponds to an activity with a Turnover Number (TON) of 13,000 and a Turnover Frequency (TOF) of 26,000.

Second Step: Separation of Copolymer and Catalyst

(1) The acrylic acid polymer (PPA; Mv (viscosity average molecular weight) = 3,000,000; 0.5% crosslinking, 21 mg) purchased from Aldrich was added to the solution containing the copolymer and the catalyst prepared above, and at room temperature for 2 hours. Stirred. Celite was thinly coated on a glass filter and the stirred solution was filtered using a vacuum pump. Most catalysts were complexed with acrylic acid polymers, collected in solid form on the filter, and the filtered solution was significantly lighter in color than the unfiltered solution. Some copolymers were taken from the filtered solution and processed to analyze the amount of cobalt contained in the copolymers with an ICP-mass spectrometer (Table 1). In addition, after removing all solvents, the copolymer was dissolved in 20 mL of methylene chloride, and the absorbance thereof was measured by an ultraviolet-visible spectrophotometer (FIG. 2).

(2) The same treatment as in (1) was carried out using a small molecular weight acrylic acid polymer (Mv = 450,000; 0.5% crosslinking, 21 mg). Some copolymers were taken from the filtered solution and processed to analyze the amount of cobalt contained in the copolymers with an ICP-mass spectrometer (Table 1). In addition, all solvents were removed, the copolymer was dissolved in 20 mL of methylene chloride, and the absorbance was measured by ultraviolet-visible spectroscopy (FIG. 2).

(3) Thinly packed silica gel (400 mg, 0.040-0.063 mm particle size (230-400 mesh), manufactured by Merck Co., Ltd.) on a glass filter, and filtered through a copolymer solution obtained in the first step. It was found that the catalyst was collected on the upper part of the silica column, and some copolymers were taken from the filtered solution and treated to analyze the amount of cobalt contained in the copolymer by an ICP-mass spectrometer (Table 1). All solvents were removed and the copolymer was dissolved in 20 mL of methylene chloride, and then absorbance was measured by ultraviolet-visible spectroscopy (FIG. 2).

(4) The same treatment as in (3) was carried out using alumina (1.0 g, manufactured by Sigma-Aldrich, neutral, about 150 mesh). The filtered solution was almost colorless but observed that some insoluble suspended solids were in the filtered solution. Some copolymers were taken from the filtered solution and processed to analyze the amount of cobalt contained in the copolymers with an ICP-mass spectrometer (Table 1). In addition, all solvents were removed, the copolymer was dissolved in 20 mL of methylene chloride, and the absorbance was measured by ultraviolet-visible spectroscopy (FIG. 2).

Third Step: Catalyst Recovery Step

The solid compound filtered out without filtration by the second step (1) and (2) was collected and dispersed in a methylene chloride solvent. Nothing was dissolved when not treated, but when 14 mg of 2,4-dinitrophenol was added, it immediately became a red solution. The red solution was collected by filtration and the solvents were all removed under vacuum reduced pressure. 2,4-dinitrophenol remaining in diethyl ether was dissolved and removed to recover 5-6 mg of a powdery solid compound. When the compound was analyzed by 1 H NMR, it was confirmed to be the same as the catalyst compound and the same activity was confirmed in the copolymerization reaction.

For the second steps (3) and (4), the silica-catalyst or alumina-catalyst complex was dispersed in methanol solvent and then the catalyst was recovered in the same manner. When the recovered compound was subjected to 1 H NMR analysis, a compound further comprising 2 moles of 2,4-dinitrophenolate per mole of cobalt was obtained, which showed a polymerization activity of about 2/3 of the initial catalytic activity.

By the following method, the same compound as the initial catalyst compound was recovered in terms of NMR spectrum and copolymerization activity. When the silica-catalyst or alumina-catalyst complex separated and recovered in the second step was dispersed in a methanol solution saturated with NaBF ₄ , the red color solution was dissolved. It was filtered and washed once or twice with methanol solution saturated with NaBF ₄ until the solution and inorganic material became colorless. The solution was collected and the solvent was removed under vacuum reduced pressure. When methylene chloride was added to the obtained solid, the brown cobalt compound was dissolved in methylene chloride and NaBF ₄ was not dissolved as a white solid, which could be separated. Excessive solid sodium 2,4-dinitrophenolate was added to the methylene chloride solution, stirred overnight, filtered, and the methylene chloride solution was taken, and the solvent was removed to obtain a brown powder. This recovered compound was confirmed to be the same as the catalyst compound when the 1H NMR analysis and showed the same activity in the copolymerization reaction.

Example 2 Copolymer Preparation Process Including a Separation and Recovery Method of a Catalyst Using a 500 mL Reactor

186 mg of the compound of Formula 10 wherein X is 2,4-dinitrophenolate, R ⁶¹ and R ⁶² are methyl and n is 3, using a 500 mL reactor, and propylene oxide (240 g, The copolymerization was carried out in the same manner using 4.13 mol). The polymerization reaction was carried out for 1 hour 15 minutes. The resulting solution was not viscous and easy to filter due to its high viscosity. Thus, 500 g of propylene oxide was added to prepare a low-viscosity solution capable of stirring and filtration. The solution was passed through a 20 mL silica (0.040-0.063 mm particle diameter (230-400 mesh) column manufactured by Merck Co., Ltd. filter) to obtain a solution containing only the copolymer without the colorless transparent catalyst. vacuum transfer) was collected in the flask and reused to obtain 115 g of copolymer (TON = 13,500; TOF = 10,800). The red solid phase collected on the silica surface was collected, transferred to the flask, and methanol was dissolved. To this, methanol solution saturated with NaBF ₄ was immediately added to give a red solution, filtered and washed one or two more times with NaBF ₄ saturated methanol solution until the solution and inorganic material became colorless. The solution was collected and the solvent was removed under vacuum reduced pressure. Methylene chloride was added to the obtained solid, and the brown cobalt compound was dissolved in methylene chloride. NaBF ₄ was not dissolved as a white solid and could be separated by adding an excess of solid sodium 2,4-dinitrophenolate to the methylene chloride solution, stirring overnight, filtering to obtain a methylene chloride solution, and removing the solvent to give a brownish color. A powder was obtained (180 mg, 97% recovery) The recovered compound was confirmed to be the same as the catalyst compound by 1 H NMR analysis and showed the same activity and selectivity in the copolymerization reaction.

1 illustrates the separation recovery scheme of the catalyst.

2 shows the absorbance of the copolymer solution after the second step.

Claims (11)

A solution obtained by dissolving the copolymer and the catalyst in the copolymer manufacturing process is contacted with a solid inorganic material, a high molecular material, or a mixture thereof, insoluble in the solution to form a complex of the solid inorganic material or high molecular material and a catalyst Separating the copolymer; And In a medium in which the solid inorganic material or the polymer material cannot be dissolved, the complex of the solid inorganic material or the polymer material and the catalyst is treated with a metal salt of an acid or a non-reactive anion so that the catalyst is dissolved out of the medium. Separating and recovering the catalyst A method of separating and recovering a catalyst from a solution in which a copolymer and a catalyst are dissolved. The method of claim 1, The contact between the solution in which the copolymer and the catalyst are dissolved and a solid inorganic material, a polymer material, or a mixture thereof Adding a solid inorganic material, a high molecular material or a mixture thereof to a solution in which the copolymer and the catalyst are dissolved and then filtering, or The solution in which the copolymer and the catalyst are dissolved is passed through a column packed with a solid inorganic material, a high molecular material, or a mixture thereof. To be carried out. The method of claim 1, The solid phase inorganic material is surface-modified or unmodified silica or alumina, and the solid phase material is a high molecular material having a functional group capable of deprotonation reaction by an alkoxy anion. The method of claim 3, wherein Wherein the functional group by which the deprotonation reaction can take place by an alkoxy anion is a sulfonic acid group, a carboxylic acid group, a phenol group or an alcohol. The method of claim 1, Wherein the catalyst comprises at least one of the functional groups of the formulas (1), (2) and (3) and the central metal is a complex having a Lewis acid group: Formula 1

Formula 2

Formula 3

Where Z is nitrogen or phosphorus; X is halogen; Aryloxy of 6 to 20 carbon atoms, carboxyl of 1 to 20 carbon atoms, alkoxy of 1 to 20 carbon atoms, alkylsulfonyl of 1 to 20 carbon atoms, with or without halogen, nitrogen, oxygen, silicon, sulfur and phosphorus Earth, or amido having 1 to 20 carbon atoms, wherein X may be coordinated with a central metal having Lewis acid groups; R ¹¹ , R ¹² , R ¹³ , R ²¹ , R ²² , R ²³ , R ²⁴ and R ²⁵ are each independently or simultaneously hydrogen; C1-C20 alkyl, C2-C20 alkenyl, C7-C20 alkylaryl, or C7-C20 aryl, with or without halogen, nitrogen, oxygen, silicon, sulfur and phosphorus Alkyl radicals; Or a metalloid radical of a Group 14 metal substituted with hydrocarbyl, wherein two of R ¹¹ , R ¹² and R ¹³ or two of R ²¹ , R ²² , R ²³ , R ²⁴ and R ²⁵ are connected to each other to form a ring Can form; R ³¹ , R ³² and R ³³ are each independently or simultaneously hydrogen; C1-C20 alkyl, C2-C20 alkenyl, C7-C20 alkylaryl, or C7-C20 aryl, with or without halogen, nitrogen, oxygen, silicon, sulfur and phosphorus Alkyl radicals; Or a metalloid radical of a Group 14 metal substituted with hydrocarbyl, wherein two of R ³¹ , R ³² and R ³³ can be linked to each other to form a ring; X 'is oxygen, sulfur or NR, wherein R is hydrogen; alkyl having 1 to 20 carbon atoms with or without at least one of halogen, nitrogen, oxygen, silicon, sulfur and phosphorus, alkenyl having 2 to 20 carbon atoms, Alkylaryl having 7 to 20 carbon atoms or arylalkyl radical having 7 to 20 carbon atoms. The method of claim 1, Alkylene oxides having 2 to 20 carbon atoms with or without copolymers substituted with halogen or alkoxy; Cycloalkene oxides having 4 to 20 carbon atoms, optionally substituted with halogen or alkoxy; And an epoxide and carbon dioxide selected from the group consisting of styrene oxide having 8 to 20 carbon atoms, optionally substituted with halogen, alkoxy or alkyl. The method of claim 1, The catalyst is a complex of formula (4); The solid inorganic material is silica or alumina, the solid polymeric material is a high molecular material comprising sulfonic acid groups, carboxylic acid groups, phenol groups or alcohol groups, and the metal salt of the non-reactive anion is MBF ₄ or MClO ₄ (where , M is Li, Na or K) Formula 4

Where M is a transition metal or a typical metal; X 'is a ligand of neutral or monovalent anion; A is oxygen or sulfur; Q is alkyl having 1 to 20 carbon atoms, cycloalkyl diradical having 3 to 20 carbon atoms, aryl diradical having 6 to 30 carbon atoms, or containing at least one of halogen, nitrogen, oxygen, silicon, sulfur and phosphorus Dioxy radical of 1 to 20; R ¹ to Each R ¹⁰ is independently or simultaneously hydrogen; C1-C20 alkyl, C2-C20 alkenyl, C7-C20 alkylaryl, or C7-C20 aryl, with or without halogen, nitrogen, oxygen, silicon, sulfur and phosphorus Alkyl radicals; Or a metalloid radical of a Group 14 metal substituted with hydrocarbyl, wherein R ¹ to R ¹⁰ Two may be linked to each other to form a ring; R ¹ to At least one or more of R ¹⁰ includes at least one of the functional groups of the formulas (1), (2) and (3), wherein X in formulas (1), (2) and (3) may be coordinated to the central metal having Lewis acid group. The method of claim 1, The catalyst is a complex of formula (5); Wherein the solid inorganic material is silica, the solid polymeric material is a polymeric material comprising carboxylic acid groups, and the metal salt of the non-reactive anion is MBF ₄ , wherein M is Li, Na or K: Formula 5

Where M 'is cobalt; X ″ is aryloxy having 6 to 20 carbon atoms, unsubstituted or substituted with a halogen, nitro group, or carboxy having 1 to 20 carbon atoms, unsubstituted or substituted with halogen; A 'is oxygen; Q 'is trans-1,2-cyclohexylene, ethylene or substituted ethylene; R ' ¹ , R' ² , R ' ⁴ , R' ⁶ , R ' ⁷ and R' ⁹ are hydrogen; R ' ⁵ and R' ¹⁰ are tert-butyl, methyl or isopropyl, At least one of R ' ³ and R' ⁸ is-[YR ⁴¹ _3-m {(CR ⁴² R ⁴³ ) _n NR ⁴⁴ R ⁴⁵ R ⁴⁶ } _m ] X " _m or-[PR ⁵¹ R ⁵² = N = PR ⁵³ R ⁵⁴ R ⁵⁵ ] X "; Y is carbon or silicon; R ⁴¹ , R ⁴² , R ⁴³ , R ⁴⁴ , R ⁴⁵ , R ⁴⁶ , R ⁵¹ , R ⁵² , R ⁵³ , R ⁵⁴ and Each R ⁵⁵ is independently or simultaneously hydrogen; C1-C20 alkyl, C2-C20 alkenyl, C7-C20 alkylaryl or C7-C20 arylalkyl, with or without halogen, nitrogen, oxygen, silicon, sulfur and phosphorus Radicals; Or a metalloid radical of Group 14 metal substituted with hydrocarbyl, R ⁴⁴ , 2 of R ⁴⁵ and R ⁴⁶ or R ⁵¹ , R ⁵² , R ⁵³ , R ⁵⁴ and Two of R ⁵⁵ may be linked to one another to form a ring; m is an integer of 1 to 3; n is an integer of 1 to 20. The method of claim 1, The catalyst is a complex of one of formulas 6 to 10; Wherein the solid phase inorganic material is silica, the solid phase polymeric material is a copolymer comprising units such as the following Formulas 11 to 15 or homopolymers consisting solely of such units, and the metal salt of the non-reactive anion is NaBF ₄ : Formula 6

Formula 7

Formula 8

Formula 9

Formula 10

Formula 11

Formula 12

Formula 13

Formula 14

Formula 15

Where M is cobalt or chromium; R ⁶¹ and R ⁶² are each independently or simultaneously hydrogen, methyl, isopropyl or tert-butyl; X is halogen; Aryloxy of 6 to 20 carbon atoms, carboxyl of 1 to 20 carbon atoms, alkoxy of 1 to 20 carbon atoms, alkylsulfonyl of 1 to 20 carbon atoms, with or without halogen, nitrogen, oxygen, silicon, sulfur and phosphorus Earth, or amido having 1 to 20 carbon atoms, wherein X may be coordinated with a central metal having Lewis acid groups; n is an integer of 1 to 20. The method of claim 1, The catalyst is a complex of formula 10; The solid inorganic material is silica, and the solid polymeric material is crosslinked acrylic resin; The acid is 2,4-dinitrophenol and the metal salt of the non-reactive anion is NaBF ₄ : Formula 10

Where M is cobalt; R ⁶¹ and R ⁶² are methyl; X is 2,4-dinitrophenolate; n is 3. A copolymer having a metal content of 15 ppm or less separated from a solution in which the copolymer and the catalyst are dissolved by the method according to any one of claims 1 to 10.

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