KR100249269B1 - Method of producing for 2-hydrocyethylmetacrylate - Google Patents

Abstract

In the present invention, a method of producing 2-hydroxyethyl methacrylate (2-hydroxyethy methacrylate) in order to solve the problems such as the color of the brown system, or a hard condensation material in the purification process, etc. The addition of methacrylic acid and ethylene oxide in the presence of a compound catalyst provides a method for preparing 2-hydroxyethyl methacrylate.

The present invention solves the problem of using a conventional iron (III) and chromium (III) compound as a catalyst by using a magnesium compound, in particular, magnesium chloride compound as a catalyst, to produce a high-purity product in high yield It becomes possible.

Description

Method for preparing 2-hydroxyethyl methacrylate

The present invention relates to a method for preparing 2-hydroxyethyl methacrylate, and more particularly, to methacrylic acid represented by general formula [I] and general formula [II] in the presence of a magnesium compound catalyst. It is related with the method of making 2-hydroxyethyl methacrylate represented by general formula [III] by making ethylene oxide represented by addition reaction.

2-hydroxyethyl methacrylate of the general formula [III] is widely used as an additive in adhesives, thermosetting paints, paper processing agents and the like.

Conventionally, when 2-hydroxyethyl methacrylate is synthesized, in addition to 2-hydroxyethyl methacrylate, which is a product, ethylene glycol monoester represented by the following general formula [VII] and diester represented by general formula [VII] It is known that ethylene glycol dimethacrylate and a polymer of 2-hydroxyethyl methacrylate represented by the general formula [VII] are produced as a by-product, which affects the yield and purity of the product. This is known to be due to the general reaction characteristics when carboxylic acids are ethoxylated, the ethoxylation reaction of the carboxylic acid occurs step by step as follows.

Conventional processes for preparing 2-hydroxyethyl methacrylate are the addition of ethylene oxide to methacrylic acid in the presence of a suitable catalyst and polymerization inhibitor.

When the reaction proceeds with the iron (III) and chromium (III) compounds, which are catalysts used in US Patent Nos. 3, 441, 599 and 3, 399, 229, etc., the reaction proceeds well. Due to the effect, the reaction mixture becomes colored and decolorization process is required for commercialization. In addition, methacrylic acid and 2-hydroxyethyl methacrylate are unstable at high temperature and easily form a polymer. Using Ⅲ) and chromium (III) compounds, high molecular weight rigid polymers are easily produced, and the polymers thus formed are attached to the inner wall of the reactor, making it difficult to remove them, and the waste generated after purifying the reaction mixture. There is a problem in the treatment of the catalyst, so a large purification cost is required.

In the conventional method, 1 mole of methacrylic acid is placed in a suitable reaction container together with a catalyst and a polymerization inhibitor, and then 1.1 to 1.3 moles of ethylene oxide are injected into the liquid state while maintaining a constant temperature, followed by reaction. The high purity 2-hydroxyethyl methacrylate was obtained by removing a catalyst component.

The present invention is to solve the above problems, the object of the present invention by using a magnesium-based compound as a catalyst when using a conventional iron (III) and chromium (III) compound as a catalyst of the brown system The present invention provides a method for preparing 2-hydroxyethyl methacrylate that can remove hard polymers generated during color or purification.

Characterization of the method for producing 2-hydroxyethyl methacrylate according to the present invention for achieving the above object is 0.1 to 10% by weight of chloride based on methacrylic acid in the addition reaction of methacrylic acid and ethylene oxide Magnesium is used as a catalyst.

Hereinafter, the present invention will be described in more detail.

The catalyst used in the present invention not only shows high activity in the synthesis of 2-hydroxyethyl methacrylate as a magnesium compound, but also does not have a special color even when reacted at a considerably high temperature, thereby simplifying the refinery. In addition, even when a polymer polymer is formed due to the failure of the reaction temperature control, it is relatively easy to remove because it does not form a hard resinous film.

Since magnesium chloride compound, which is a representative magnesium compound used in the present invention, has high activity, the reaction is terminated within 1-10 hours when the reaction temperature is maintained at 90 ° C. at normal pressure even with 0.1 to 7% by weight of the total amount of the reactants. The magnesium chloride compound is selected from broth magnesium chloride or anhydrous magnesium chloride.

In this case, the obtained material showed a purity of 99% or more (HPLC analysis) and a yield of 98% (based on the weight of methacrylic acid).

In addition, in the present invention, heat treated magnesium chloride may be used as a catalyst, which is selected from broth magnesium chloride, tetrahydrated magnesium chloride or anhydrous magnesium chloride, and heat treated at 100 to 500 ° C. for 10 minutes to 48 hours.

Magnesium chloride or heat-treated magnesium chloride used as a catalyst in the present invention can greatly increase the reaction conversion rate, facilitate the removal of the polymerization material during polymerization, and because the reaction mixture does not have color, unreacted methacrylic acid and The catalyst component can be removed. Therefore, according to the present invention, it is possible not only to obtain a high-purity product in high yield, but also to synthesize the best 2-hydroxyethyl methacrylate having a color and transparency almost similar to that of distilled water.

Hereinafter, the present invention will be described in more detail with reference to Examples.

Example 1

3 g of broth magnesium chloride and 0.2 g of a polymerization inhibitor p-methoxyphenol were added to 100 g (1.2 mol) of methacrylic acid, and the mixture was stirred well while gradually heating. When the temperature reached 85 ° C., 60 g of ethylene oxide was slowly injected into the liquid and gaseous state. The reaction mixture was maintained at 85 ° C. while ethylene oxide was injected to obtain a colorless reaction mixture. 2-hydroxyethyl methacrylate obtained by purifying the reaction mixture has a purity of 98% or more, a total acid value of 2 or less, a halogen number 5 or less, and a yield of 90%.

Example 2

To the 100 g (1.2 mol) of methacrylic acid, 3 g of anhydrous magnesium chloride and 0.2 g of a polymerization inhibitor p-methoxyphenol were added, and the mixture was stirred well while gradually heating. When the temperature reached 55 ° C., 60 g of ethylene oxide was injected into the reactor. While injecting ethylene oxide, the reaction temperature was maintained at 55 ° C. to obtain a colorless reaction mixture. The 2-hydroxyethyl methacrylate obtained by purifying the reaction mixture has a purity of 98% or more, an acid value of 2 or less, a Hazen number of 5 or less, and a yield of 90%.

Example 3

100 g (1.2 mole) of methacrylic acid, 3 g of anhydrous magnesium chloride and 0.2 g of a polymerization inhibitor p-methoxyphenol were added to the reaction vessel, and the mixture was stirred well with a magnetic bar while gradually heating. When the reaction vessel was heated in a water bath and the temperature reached 70 ° C, 60 g of ethylene oxide was slowly injected into the liquid and gaseous state. The reaction temperature during the injection of ethylene oxide was maintained at the same temperature as the injection temperature of ethylene oxide to give a colorless reaction mixture. 2-hydroxyethyl methacrylate obtained by purifying the reaction mixture has a purity of 98% or more, a total acid value of 2 or less, a Hazen number 5 or less, and a yield of 95%.

Example 4

To 150 g (1.7 mol) of methacrylic acid, 5% by weight of broth magnesium chloride (based on weight of methacrylic acid) and 0.2% by weight of p-methoxyphenol polymerization inhibitor (based on weight of methacrylic acid) are added to the reaction vessel, and the mixture is heated slowly. Stirred. When the temperature reached 55 ℃ ethylene oxide was injected into the reaction vessel at a rate of 10g per hour. The reaction temperature during the injection of ethylene oxide was maintained at 55 ° C. to obtain a colorless reaction mixture. 2-hydroxyethyl methacrylate obtained by purifying the reaction mixture has a purity of 98% or more, a total acid value of 2 or less, a Hazen number 5 or less, and a yield of 92%.

Example 5

Ethylene oxide was injected into a reactor in which 150 g of methacrylic acid, 7.5 g of shooter magnesium chloride, and 0.3 g of p-methoxyphenol were mixed at a rate of 10 g per hour. The temperature at which ethylene oxide was injected was 70 ° C., while the reaction temperature was maintained at 70 ° C. while ethylene oxide was injected, a colorless reaction mixture was obtained. 2-hydroxyethyl methacrylate obtained by purifying the reaction mixture has a purity of 98% or more, a total acid value of 2 or less, a Hazen number 5 or less, and a yield of 95%.

Example 6

After 150 g of methacrylic acid was added to the reactor, 0.08 mol of anhydrous magnesium chloride and 0.002 mol of p-methoxyphenol were added thereto, and the mixture was stirred well while slowly heating for 30 minutes. When the reactor temperature reached 85 ° C, 1.8 mol of ethylene oxide was slowly injected. The reaction temperature during the injection of ethylene oxide was maintained at 85 ℃ to obtain a colorless reaction mixture. 2-hydroxyethyl methacrylate obtained by purifying the reaction mixture has a purity of 98% or more, a total acid value of 2 or less, a Hazen number 5 or less, and a yield of 97%.

Example 7

90 g of ethylene oxide was slowly injected into a reactor containing 150 g of methacrylic acid, 10 g of broth magnesium chloride, and 0.3 g of p-methoxyphenol. The temperature at which ethylene oxide was injected was 70 ° C., and the reaction temperature while ethylene oxide was injected was maintained at the same temperature as the ethylene oxide injection temperature. The reaction was terminated within 10 hours, yielding a colorless reaction mixture. The 2-hydroxyethyl methacrylate obtained by purifying the synthesized reaction mixture has a purity of 98% or more, an acid value of 2 or less, a Hazen number 5 or less, and a yield of 93%.

Example 8

After adding 200 g (2.3 mol) of methacrylic acid, 14 g of anhydrous magnesium chloride, and 0.4 g of p-methoxyphenol, the mixture was stirred well while slowly heating for about 30 minutes. When the reactor temperature reached 85 ° C, 2.4 mol of ethylene oxide was slowly injected into the reactor. While the ethylene oxide was injected, the reaction temperature was the same as the injection temperature of ethylene oxide to give a colorless reaction mixture. 2-hydroxyethyl methacrylate obtained by purifying the reaction mixture has a purity of 98% or more, a total acid value of 2 or less, a halogen number 5 or less, and a yield of 97%.

Example 9

200 g (2.3 mol) of methacrylic acid, 14 g of anhydrous magnesium chloride and 0.4 g of a polymerization inhibitor p-methoxyphenol were added to the well-dried reactor, and nitrogen was flowed into the reactor for about 5 minutes. The reactor containing the mixture was stirred well while heating slowly in a water bath. The temperature inside the reactor was maintained at 55 ° C. At the end of the reaction, the reactor was removed from the water bath and cooled slowly at room temperature. At this time, a colorless reaction mixture was obtained. The 2-hydroxyethyl methacrylate obtained by purifying the reaction mixture has a purity of 98% or more, an acid value of 2 or less, a Hazen number of 5 or less, and meat of 97%.

Example 10

5 g of anhydrous magnesium chloride and 0.2 g of a polymerization inhibitor p-methoxyphenol were added to 100 g (1.2 mol) of methacrylic acid, and the mixture was stirred well while gradually heating. When the temperature reached 55 ℃ 60g ethylene oxide was slowly injected into the reaction vessel in the liquid and gaseous state. While injecting ethylene oxide, the reaction temperature was maintained at 55 ° C. to obtain a colorless reaction mixture.

2-hydroxyethyl methacrylate obtained by purifying the reaction mixture has a purity of 98% or more, a total acid value of 2 or less, a halogen number 5 or less, and a yield of 98%.

Example 11

14 g of heat-treated magnesium chloride and 0.4 g of p-methoxyphenol were added to 2.3 moles of methacrylic acid, and the mixture was stirred well while gradually heating. When the temperature reached 85 ° C, 2.4 mol of ethylene oxide was slowly injected into the reactor. The reaction temperature was subsequently continued while maintaining the injection temperature of ethylene oxide to obtain a colorless reaction mixture. 2-hydroxyethyl methacrylate obtained by purifying the reaction mixture has a purity of 98% or more, a total acid value of 2 or less, a halogen number 5 or less, and a yield of 95%.

Example 12

3 g of broth magnesium chloride and 0.2 g of a polymerization inhibitor p-methoxyphenol which were heat-treated in 100 g (1.2 mol) of methacryl were added to a well-dried reactor, and the mixture was stirred well while gradually heating. When the temperature of the reactor reached 55 ° C., ethylene oxide was slowly injected into the reactor. The reaction temperature was maintained at 55 ° C. until the reaction was completed to react methacrylic acid with ethylene oxide to obtain a colorless reaction mixture. 2-hydroxyethyl methacrylate obtained by purifying the reaction mixture has a purity of 98% or more, a total acid value of 2 or less, a halogen number 5 or less, and a yield of 98%.

Example 13

Heat-treated anhydrous magnesium chloride was used as a catalyst and the polymerization inhibitor was p-methoxyphenol, and 1.7 mol of methacrylic acid was added to the reactor, and then 5% by weight of catalyst and 0.2% by weight of polymerization inhibitor were added in a weight ratio to methacrylic acid. Stir well. When the temperature inside the reactor was gradually raised to 70 ° C, 1.8 mol of ethylene oxide was slowly injected into the reaction vessel. The reaction was carried out while maintaining the reaction temperature at 70 ℃ to obtain a colorless reaction mixture. The 2-hydroxyethyl methacrylate obtained by purifying the reaction mixture after slowly cooling the reactor at room temperature after removing it from the water bath has a purity of 98% or more, an acid value of 2 or less, a halogen number 5 or less, and a yield of 99%.

Example 14

The mixture was added together with 0.008 moles of heat-treated magnesium chloride and 1.7 moles of methacrylic acid of 0.002 moles of p-methoxyphenol, and then the mixture was stirred well for 30 minutes while heating slowly. When the reactor temperature reached 55 ° C., 1.8 mol of ethylene oxide was slowly injected into the liquid and gaseous state. While injecting ethylene oxide, the reaction temperature was maintained at 55 ℃ to obtain a colorless reaction mixture. 2-hydroxyethyl methacrylate obtained by purifying the reaction mixture has a purity of 98% or more, a total acid value of 2 or less, a charge number of 5 or less, and a yield of 90%.

Example 15

1.7 mol of methacrylic acid was added to the reactor using heat-treated broth magnesium chloride as a catalyst and p-methoxyphenol as a polymerization inhibitor, and 7.3 g of a catalyst and 0.2% by weight of a polymerization inhibitor were added, followed by stirring the mixture well. When the reactor was heated to a temperature of 70 ° C., 1.8 mol of ethylene oxide was slowly injected into the reaction vessel in liquid and gaseous state. The reaction was carried out while maintaining the reaction temperature at 70 ℃ to obtain a colorless reaction mixture. 2-hydroxyethyl methacrylate obtained by purifying the reaction mixture has a purity of 98% or more, a total acid value of 2 or less, a halogen number 5 or less, and a yield of 95%.

Example 16

14 g of anhydrous magnesium chloride and 0.4 g of a polymerization inhibitor p-methoxyphenol were added to 200 g (2.3 mol) of methacrylic acid, and the mixture was stirred well while gradually heating. When the temperature reached 85 ° C., 102 g of ethylene oxide was slowly injected. The reaction mixture was maintained at 85 ° C. while ethylene oxide was injected to obtain a colorless reaction mixture. 2-hydroxyethyl methacrylate obtained by purifying the reaction mixture has a purity of 98% or more, a total acid value of 2 or less, a halogen number 5 or less, and a yield of 99%.

Example 17

60 g of ethylene oxide was slowly injected into a well-dried reactor in which liquid and gaseous phases were mixed with 100 g of methacrylic acid, 3 g of heat treated tetrachloride magnesium chloride and 0.2 g of a polymerization inhibitor p-methoxyphenol. The temperature inside the reactor at this time was 70 ℃, the reaction temperature while the ethylene oxide is injected was maintained at the same temperature as the ethylene oxide injection temperature. The reaction was terminated within 10 hours, yielding a colorless reaction mixture. The 2-hydroxyethyl methacrylate obtained by purifying the synthesized reaction mixture has a purity of 98% or more, a total acid value of 2 or less, a Hazen number 5 or less, and a yield of 98%.

Example 18

After heat-treating with 200 g of methacrylic acid into a well-dried reactor, 7% by weight of broth magnesium chloride and 0.4 g of p-methoxyphenol were added, and nitrogen was flowed into the reactor for about 5 minutes. The mixture was stirred well while the reactor was slowly heated in a water bath. The temperature inside the reactor was maintained at 85 ° C.

At the end of the reaction, the reactor was removed from the water bath and cooled slowly at room temperature. At this time, a colorless reaction mixture was obtained. 2-hydroxyethyl methacrylate obtained by purifying this reaction mixture has a purity of 98% or more, a acid value of 2 or less, a Hazen number 5 or less, and a yield of 97%.

Comparative Example 1

3 g of aluminum chloride and 0.2 g of a polymerization inhibitor p-methoxyphenol were added to 100 g (1.2 mol) of methacrylic acid, and the mixture was stirred well while gradually heating. When the temperature reached 85 ℃ 60g ethylene oxide was slowly injected into the reaction vessel in the liquid and gaseous state. The reaction mixture was obtained while maintaining the reaction temperature at 85 ° C while injecting ethylene oxide. The 2-hydroxyethyl methacrylate obtained by purifying the reaction mixture has a purity of 80% or more, an acid value of 400 or more, a Hazen number of 100 or more, and a yield of 65%.

Comparative Example 2

5 g of iron chloride and 0.2 g of p-methoxyphenol were added to 100 g (1.2 mol) of methacrylic acid, and the mixture was stirred well while gradually heating. When the temperature in the reactor reached 85 ℃ ethylene oxide was injected into the reaction vessel at a rate of 5g per hour. The reaction temperature was then continued while maintaining the reaction temperature at 85 ° C., which is an injection temperature of ethylene oxide, to obtain a brown reaction mixture. 2-hydroxyethyl methacrylate obtained by purifying the reaction mixture has a purity of 95% or more, a acid value of 200 or more, a Hazen number of 100 or more, and a yield of 80%.

Comparative Example 3

To the 50 ml methacrylic acid was added 0.002 mol of Cu (NO ₃ ) .2H ₂ O and 0.33% by weight of p-methoxyphenol (based on the weight of methacrylic acid), and the mixture was stirred well while gradually heating. When the temperature in the reactor reached 85 ℃ 30ml of ethylene oxide was injected into the reaction vessel. The reaction mixture was continuously maintained at 55 ° C., which is an injection temperature of ethylene oxide, to obtain a reaction mixture. 2-hydroxyethyl methacrylate obtained by purifying the reaction mixture has a purity of 95% or more, a total acid value of 100 or more, a Hazen number of 50 or more, and a yield of 85%.

Claims (4)

In the addition reaction of methacrylic acid and ethylene oxide, magnesium chloride is added as a catalyst at 0.1 to 10% by weight based on methacrylic acid. The method for preparing 2-hydroxyethyl methacrylate according to claim 1, wherein the magnesium chloride is selected from magnesium hexachloride, magnesium tetrachloride, and anhydrous magnesium chloride. The method for preparing 2-hydroxyethyl methacrylate according to claim 1, wherein the magnesium chloride is magnesium chloride heat-treated at a temperature of 100 to 500 ° C. for 10 minutes to 48 hours. The method for preparing 2-hydroxyethyl methacrylate according to claim 3, wherein the heat treated magnesium chloride is selected from magnesium hexachloride, magnesium tetrachloride and anhydrous magnesium chloride.