JP2006104168A - Method for producing (meth)acrylic acid ester - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for producing a high-purity (meth)acrylic acid ester in good yield by using an alcohol having an ether group by efficiently reducing the content of a peroxide which has a possibility of polymerizing the alcohol having the ether group. <P>SOLUTION: The method for producing the (meth)acrylic acid ester involves heating the alcohol having the ether group in the presence of a catalyst and an antioxidant to 50-150°C to decompose the peroxide, and using the resultant alcohol having the ether group as a raw material for producing the (meth)acrylic acid ester. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a method for producing a (meth) acrylic acid ester. More specifically, for example, a (meth) acrylic acid ester that can be suitably used as a reactive diluent for a curable resin that is cured by light such as ultraviolet rays or the like, such as a raw material such as a paint, an adhesive, a pressure-sensitive adhesive, a synthetic resin, or a fiber. Relates to the manufacturing method.

  Alcohols having ether groups, such as cyclic ether group-containing alcohols and polyether group-containing alcohols, are chemically unstable and, for example, are easily oxidized in the air to produce peroxides. Therefore, an alcohol having an ether group usually contains a peroxide as an impurity. When an alcohol having an ether group containing this peroxide is reacted with an unsaturated carboxylic acid, Since this peroxide acts as a polymerization initiator, the produced ester may be polymerized.

  Therefore, in recent years, methods for preventing polymerization in the production of (meth) acrylic acid esters using an alcohol having an ether group have been studied. As an example, when an unsaturated carboxylic acid and a cyclic alcohol are subjected to an esterification reaction, an organic sulfonic acid is added to the cyclic alcohol, followed by heat treatment, and then an unsaturated carboxylic acid is added to perform an esterification reaction. (For example, refer to Patent Document 1).

  According to this method, the amount of peroxide produced when the cyclic alcohol is esterified while blowing air in the presence of an acid catalyst and a polymerization inhibitor can be reduced. However, when an alcohol having an ether group is used instead of a cyclic alcohol, a large amount of peroxide is generated, and the generated peroxide acts as a polymerization initiator, so that the alcohol having an ether group is polymerized. There is a risk.

JP 58-217333 A

  The present invention has been made in view of the prior art, and efficiently reduces the content of peroxide that may polymerize an alcohol having an ether group, and is highly purified using the alcohol having an ether group. It is an object of the present invention to provide a method capable of producing the (meth) acrylic acid ester in a high yield.

  In the present invention, an alcohol having an ether group is heated to 50 to 150 ° C. in the presence of a catalyst and an antioxidant to decompose a peroxide, and then the alcohol having an ether group is converted to a (meth) acrylic ester. The present invention relates to a method for producing a (meth) acrylic acid ester, which is used as a raw material in production.

  In this specification, “(meth) acrylic acid” means “acrylic acid” and / or “methacrylic acid”.

  According to the production method of the present invention, it is possible to efficiently reduce the content of a peroxide that may polymerize an alcohol having an ether group, and a high-purity (meth) can be obtained using the alcohol having an ether group. The effect that the acrylic ester can be produced with high yield is exhibited.

  The present invention has one major feature in that an alcohol having an ether group is heated to 50 to 150 ° C. in the presence of a catalyst and an antioxidant. In the present invention, since the alcohol having an ether group is heated in the state where the catalyst and the antioxidant coexist in this way, as a synergistic effect due to the coexistence of both, the peroxide contained in the alcohol having the ether group An excellent effect that the content can be reduced in a short time is exhibited.

  Furthermore, accompanying the synergistic effect, it effectively suppresses the amount of peroxide produced when the alcohol having an ether group with reduced peroxide content is reacted with acrylic acid or methyl acrylate. The excellent effect of being able to do is also expressed.

  In this specification, the alcohol having an ether group is an alcohol having an alcoholic hydroxyl group and an ether group. The alcohol having an ether group may be linear or cyclic, and may have a branched chain.

  Representative examples of alcohols having ether groups include ring-opened polymers of alkylene oxides, alcohols having ether groups obtained by adding alkylene oxides to alcohols and phenols, etc. It is not limited to illustration only.

  Examples of the ring-opening polymer of alkylene oxide include diethylene glycol, triethylene glycol, tetraethylene glycol, polyethylene glycol, dipropylene glycol, tripropylene glycol, tetrapropylene glycol, and polypropylene glycol. It is not limited to only.

  Specific examples of the alcohol used as a raw material for the alcohol having an ether group include monovalent aliphatic alcohols having 1 to 22 carbon atoms such as methanol, ethanol, propanol, butanol, pentanol, and hexanol; 1,3-butanediol Divalent aliphatic alcohols having 4 to 12 carbon atoms such as 1,4-butanediol, 1,6-hexanediol, 1,9-nonanediol; cyclopropanol, cyclobutanol, cyclopentanol, cyclohexanol, cyclohexane Examples thereof include alicyclic alcohols having 3 to 22 carbon atoms such as dimethylol, adamantanol and norbornol, but the present invention is not limited to such examples.

  Examples of the alcohol having an ether group obtained by adding an alkylene oxide to an alcohol or phenol include an ether group obtained by adding an alkylene oxide such as ethylene oxide or propylene oxide to the alcohol or phenol. However, the present invention is not limited to such examples.

  Examples of the cyclic alcohol having an ether group include cyclic alcohols having a skeleton such as an epoxy skeleton, an oxetane skeleton, a tetrahydrofuran skeleton, a tetrahydropyran skeleton, a dioxane skeleton, and a dioxolane skeleton. It is not limited.

  Among alcohols having an ether group, alcohols having an ether group having an unsaturated double bond in the molecule and alicyclic alcohols having an unsaturated double bond in the molecule are left in the air. However, the production method of the present invention can be suitably applied to the case of using these alcohols.

  As a catalyst, when an alcohol having an ether group is reacted with (meth) acrylic acid, a dehydrated ester catalyst can be used, and an alcohol having an ether group is reacted with an alkyl ester of (meth) acrylic acid. In this case, a transesterification catalyst can be used.

  Examples of the dehydrating ester catalyst include sulfuric acid, p-toluenesulfonic acid, benzenesulfonic acid, xylenesulfonic acid, methanesulfonic acid and the like, and these can be used alone or in admixture of two or more. Of these, p-toluenesulfonic acid is preferred.

  Examples of the transesterification catalyst include tin compounds such as tin octylate, dibutyltin dilaurate, monobutyltin oxide, dibutyltin oxide, dioctyltin oxide, stannous chloride, tetraethyl titanate, tetraisopropyl titanate, tetrabutyl titanate, tetramethoxy Transition metal compounds such as titanium compounds such as titanate, tetraethoxy titanate, tetrabutoxy titanate, thallium compounds, lead compounds, chromium compounds; alkali metal alcoholates such as sodium methylate, sodium ethylate, lithium methylate, lithium ethylate; calcium Alkaline earth metal alcoholates such as methylate, calcium ethylate, magnesium methylate, magnesium ethylate; aluminum methylate, Aluminum alcoholate such as Rumi um ethylate; and lithium hydroxide. Among these, tin compounds such as dibutyltin oxide and dioctyltin oxide, and titanium compounds such as tetramethoxy titanate, tetraethoxy titanate, and tetrabutoxy titanate are preferable.

  The amount of the catalyst increases the reaction rate, and in view of the fact that even if it is used in a large amount, a significant improvement in the reaction rate cannot be expected and is not economical, 0.001 to 0 per mol of the alcohol having an ether group .1 mole, preferably 0.01 to 0.05 mole.

  Examples of the antioxidant include hydroquinone, methoquinone (hydroquinone monomethyl ether), 2,6-di-tert-butyl-4-methylphenol, and 4,4′-butylidene-bis (3-methyl-6-tert-butylphenol). ), 2,2′-methylene-bis (4-methyl-6-tert-butylphenol), 2,2′-methylene-bis (4-ethyl-6-tert-butylphenol), 2,4′-thio-bis (3-methyl-6-tert-butylphenol), 3- (4′-hydroxy-3 ′, 5′-di-tert-butylphenyl) propionic acid-n-octadecyl, 1,3,5-tris (3 ′ , 5′-di-t-butyl-4-hydroxybenzyl) isocyanuric acid, 1,1,3-tris (2-methyl-4-hydroxy-5-tert-butylphenyl) butane, butyryl (Methyl-butylphenol), tetrabis [methylene-3- (3 ′, 5′-di-t-butyl-4′-hydroxyphenyl) propionate] methane, 3,6-dioxaoctamethylene-bis [3- ( 3-tert-butyl-4-hydroxy-5-methylphenyl) propionate], 1,3,5-trimethyl-2,4,6-tris (3,5-di-tert-butyl-4-hydroxybenzyl) benzene Phenolic compounds such as 4-hydroxy-2,2,6,6-tetramethylpiperidine-N-oxyl, N-oxyl such as 4-benzoyloxy-2,2,6,6-tetramethylpiperidine-N-oxyl Oxyl compounds; copper compounds such as cuprous chloride; phenothiazine, 4-hydroxy-2,2,6,6-tetramethylpiperidine, 4-benzoyloxy Amino compounds such as 2,2,6,6-tetramethylpiperidine; 1,4-dihydroxy-2,2,6,6-tetramethylpiperidine, 1-hydroxy-4-benzoyloxy-2,2,6 Examples thereof include hydroxylamine such as 6-tetramethylpiperidine, and these can be used alone or in admixture of two or more.

  Among the antioxidants, methoquinone and phenolic compounds are preferable, and methoquinone and 2,6-di-t-butyl-4-methylphenol are more preferable.

  The amount of the antioxidant efficiently reduces the content of the peroxide contained in the alcohol having an ether group, and a large amount of the antioxidant remains in the (meth) acrylic acid ester to be generated. From the viewpoint of suppressing the inhibition of the polymerizability of the (meth) acrylic acid ester, it is desired to be 10 to 10000 ppm, preferably 50 to 1000 ppm with respect to the mass of the alcohol having an ether group.

  When the alcohol having an ether group is heated in the presence of a catalyst and an antioxidant, an organic solvent can be used.

  As the organic solvent, those which do not easily generate peroxide are preferable. Examples of the organic solvent include aliphatic hydrocarbon compounds such as n-pentane, i-pentane, n-hexane, 2-methylpentane, n-heptane, i-heptane, n-octane, and i-octane, cyclohexane, and the like. The alicyclic hydrocarbon compounds and aromatic hydrocarbon compounds such as benzene, toluene and xylene are exemplified, but the present invention is not limited to such examples. Of these, cyclohexane is preferred.

  The amount of the organic solvent varies depending on the type of the organic solvent and cannot be determined unconditionally. However, water or alkyl alcohol generated during the esterification reaction or transesterification reaction is efficiently removed out of the system, and the ether group is removed. From the viewpoint of efficiently reducing the peroxide contained in the alcohol having, it is usually desired to be 5 to 200 parts by weight, preferably 20 to 100 parts by weight per 100 parts by weight of the alcohol having an ether group.

  Examples of the method of heating an alcohol having an ether group in the presence of a catalyst and an antioxidant include, for example, a method of heating an alcohol having an ether group, a catalyst, an antioxidant and an organic solvent and heating the resulting mixture. Is mentioned.

  The heating temperature when heating an alcohol having an ether group in the presence of a catalyst and an antioxidant increases the decomposition rate of the peroxide contained in the alcohol having an ether group and stabilizes the alcohol having an ether group. From the viewpoint of enhancing the properties, it is 50 to 150 ° C, preferably 100 to 130 ° C.

  The heating is desirably performed until the amount of peroxide contained in the alcohol having an ether group is 20 ppm or less, preferably 10 ppm or less, from the viewpoint of suppressing polymerization of the (meth) acrylic acid ester to be generated. In addition, the amount of peroxide contained in the alcohol having an ether group is a value when measured by the “method for measuring the amount of peroxide” described in “Examples” described later.

  The atmosphere in the system at the time of heating is preferably an inert gas such as nitrogen gas, argon gas or helium gas from the viewpoint of preventing oxidation of alcohol having an ether group.

  Thus, when an alcohol having an ether group is heated in the presence of a catalyst and an antioxidant to decompose the peroxide, the peroxide contained in the alcohol having an ether group can be efficiently removed. it can. Therefore, a high-purity (meth) acrylic acid ester can be produced with high yield using an alcohol having an ether group from which the peroxide has been removed by decomposition.

  The target compound (meth) acrylic acid ester can be obtained by reacting an alcohol having an ether group after decomposing the peroxide with (meth) acrylic acid or an alkyl ester thereof.

  In addition, in order to distinguish clearly the alcohol which has an ether group used as a raw material, and the alcohol which has an ether group after decomposing a peroxide, the alcohol which has an ether group after decomposing a peroxide Is hereinafter referred to as “peroxide-decomposing alcohol”.

  When reacting the peroxide-decomposing alcohol with (meth) acrylic acid or its alkyl ester, the alcohol having the ether group is heated in the presence of a catalyst and an antioxidant to decompose the peroxide. The reaction mixture obtained by can be used.

  The reaction between the peroxide-decomposing alcohol and (meth) acrylic acid is a dehydration reaction, while the reaction between the peroxide-decomposing alcohol and (meth) acrylic acid alkyl ester is an ester exchange reaction.

  The amount of (meth) acrylic acid or its alkyl ester increases the reaction rate, and from the viewpoint of reducing the remaining amount of unreacted peroxide-decomposing alcohol or (meth) acrylic acid or its alkyl ester, peroxide decomposition It is desirable that the amount is 0.5 to 5 mol, preferably 1.5 to 3 mol, per mol of alcohol.

  The reaction temperature for reacting the peroxide-decomposing alcohol with (meth) acrylic acid or an alkyl ester thereof varies depending on the type of the peroxide-decomposing alcohol and cannot be determined unconditionally. The temperature can be adjusted within a temperature range of ˜150 ° C., preferably 80 to 130 ° C.

  In addition, when reacting the peroxide-decomposing alcohol with (meth) acrylic acid or an alkyl ester thereof, for example, a compressor is used from the viewpoint of preventing the polymerization of (meth) acrylic acid or the alkyl ester thereof. For example, an oxygen-containing gas such as air is preferably blown into the mixture of the two. For example, when air is used as the oxygen-containing gas, the amount of oxygen-containing gas blown in prevents (meth) acrylic acid or its alkyl ester from polymerizing and suppresses peroxide-decomposed alcohol from being oxidized again. From this viewpoint, it is preferably 0.01 to 1 L / hr per mole of peroxide-decomposing alcohol.

  Further, water or alkyl alcohol is by-produced by the reaction of the peroxide-decomposing alcohol with (meth) acrylic acid or an alkyl ester thereof. The by-produced water or alkyl alcohol is preferably reacted while removing it outside the system in order to increase the reaction efficiency between the peroxide-decomposing alcohol and (meth) acrylic acid or its alkyl ester.

  The inside of the system during the reaction of the peroxide-decomposing alcohol with (meth) acrylic acid or its alkyl ester may be at normal pressure or under reduced pressure.

  The reaction time between the peroxide-decomposing alcohol and (meth) acrylic acid or an alkyl ester thereof varies depending on the reaction conditions and cannot be determined unconditionally. The reaction can be carried out until no water or alkyl alcohol is produced by the reaction. The reaction time required at that time varies depending on the reaction conditions and is usually about 2 to 20 hours.

  Thus, according to the production method of the present invention, it is possible to efficiently reduce the peroxide content contained in the alcohol having an ether group. The (meth) acrylic acid ester can be produced with good yield.

  Next, the present invention will be described in more detail based on examples, but the present invention is not limited to such examples.

Example 1
After replacing the inside of a 1 L four-necked flask equipped with a stirrer with nitrogen gas, 224.4 g of tetrahydrofurfuryl alcohol, 0.9 g of methoquinone, 2,6-di-t-butyl-4-methylphenol were put into the flask. 0.3 g, 16.7 g of paratoluenesulfonic acid and 460.0 g of cyclohexane were mixed with a stirrer, and the amount of peroxide in the resulting mixture was examined based on the following method for measuring the amount of peroxide. there were.

  The obtained mixture was heated to 81 ° C. with stirring, and stirred at the same temperature for 1 hour to obtain a peroxide-decomposing alcohol.

  When the peroxide amount of the obtained peroxide decomposing alcohol was examined, the peroxide amount was 5 ppm.

  Next, 166.3 g of acrylic acid was added to the flask and mixed, and then the mixture was mixed with air at a flow rate of 0.11 L / hr under atmospheric pressure using a compressor (air per mole of acrylic acid). And the temperature was raised to 81 to 90 ° C., and the esterification reaction was carried out until no water was produced while removing by-produced water out of the system.

  The obtained reaction mixture was recovered, and the yield and purity of the produced tetrahydrofurfuryl acrylate were examined. The yield was 91% and the purity was 98.5%.

  In addition, when taking out a reaction mixture from a flask, adhesion of the polymer was not recognized in the flask.

[Measurement method of peroxide amount]
(1) Prepare two 300 mL Erlenmeyer flasks, and add 40 mL of isopropyl alcohol and 2 mL of glacial acetic acid into each Erlenmeyer flask.

(2) In one Erlenmeyer flask (hereinafter referred to as “flask A”), 25 g of a sample for measuring the amount of peroxide using a direct balance is precisely weighed and added. The other Erlenmeyer flask (hereinafter referred to as Flask B) is used as it is without adding anything, and is used for a blank test.

(3) 10 mL of saturated aqueous potassium iodide solution and 40 mL of isopropyl alcohol are mixed and allowed to stand, and then 10 mL of the supernatant is added to flasks A and B, respectively.

(4) After the flasks A and B were heated in an oil bath set at 80 ° C. for 5 minutes, 0.01 mol / L sodium thiosulfate aqueous solution was dropped into each Erlenmeyer flask until the yellow color of the solution disappeared, and the titration was performed. Measure the amount.

(5) Formula:
[Peroxide content (ppm)]
= [(PQ) × 0.01 × F × 34 × 1/2 × 1000] ÷ M
[Wherein, P is the titration amount in flask A (mL), Q is the titration amount in flask B (mL), F is the titer of 0.01 mol / l sodium thiosulfate solution, M is the amount of sample (g) Show
Based on the above, the peroxide amount (ppm) is obtained.

Example 2
After replacing the inside of a 1 L four-necked flask equipped with a stirrer connected to a 15-stage old show with nitrogen gas, 255.3 g of tetrahydrofurfuryl alcohol, 0.9 g of methoquinone, 2,6-di-t-butyl- When 0.9 g of 4-methylphenol, 2.5 g of dioctyltin oxide and 80.0 g of hexane were mixed and the amount of peroxide in the obtained mixture was measured in the same manner as in Example 1, it was 220 ppm.

  The obtained mixture was heated to 81 ° C. with stirring, and stirred at the same temperature for 1 hour to obtain a peroxide-decomposing alcohol.

  When the peroxide amount of the obtained peroxide-decomposing alcohol was examined, the peroxide amount was 8 ppm.

  Next, 494.0 g of methyl acrylate was added to the flask and mixed, and then the mixture was mixed with air at a flow rate of 0.11 L / hr under normal pressure using a compressor (per mole of methyl acrylate). The amount of air was 0.05 L / hr), the temperature was raised to 90 to 100 ° C., and the transesterification reaction was performed until water was not generated while removing by-produced methanol out of the system.

  The obtained reaction mixture was recovered, and the yield and purity of the produced tetrahydrofurfuryl acrylate were examined. The yield was 95% and the purity was 99.7%.

  In addition, when taking out a reaction mixture from a flask, adhesion of the polymer was not recognized in the flask.

Comparative Example 1
In a 1 L four-necked flask equipped with a stirrer connected to a 15-stage old show, 255.3 g of tetrahydrofurfuryl alcohol, 0.9 g of methoquinone, 2,6-di-t-butyl-4-methylphenol 0 0.9 g, dioctyltin oxide 2.5 g and hexane 80.0 g were mixed at room temperature (about 23 ° C.), and the amount of peroxide in the system was measured in the same manner as in Example 1. As a result, it was 220 ppm.

  Next, 494.0 g of methyl acrylate was added to the flask and mixed, and then the mixture was obtained under normal pressure, and air was supplied to the mixture at a flow rate of 0.11 L / hr (per mole of methyl acrylate). The amount of air was 0.05 L / hr), the temperature was raised to 90 to 100 ° C., and the transesterification reaction was performed until water was not generated while removing by-produced methanol out of the system.

  The obtained reaction mixture was recovered, and the yield and purity of the produced tetrahydrofurfuryl acrylate were examined. The yield was 88% and the purity was 99.3%.

  In addition, when taking out a reaction mixture from a flask, adhesion of the white polymer was recognized in the flask.

  From the above results, according to Examples 1 and 2, the operation of preparing a peroxide-decomposing alcohol was performed by heating an alcohol having an ether group in the presence of a catalyst and an antioxidant. The content of the peroxide contained in the alcohol having an ether group can be efficiently reduced. Compared with Comparative Example 1, high-purity (meth) acrylic is produced without by-producting the polymer. It turns out that an acid ester can be manufactured with a sufficient yield.

Experimental Example 1-1
In Example 1, the mixture of tetrahydrofurfuryl alcohol, methoquinone, 2,6-di-t-butyl-4-methylphenol, paratoluenesulfonic acid and cyclohexane was heated to 81 ° C. while stirring, and stirred at the same temperature. The change with time in the amount of peroxide was investigated. The result is shown in FIG.

Experimental Example 1-2
In Example 2, the mixture of tetrahydrofurfuryl alcohol, methoquinone, 2,6-di-tert-butyl-4-methylphenol, dioctyltin oxide and hexane was heated to 81 ° C. with stirring and stirred at the same temperature. Changes in the amount of peroxide over time were examined. The result is shown in FIG.

Experimental Example 1-3
In Experimental Example 1-2, the same operation as in Experimental Example 1-2 was performed, except that the antioxidants (methoquinone and 2,6-di-t-butyl-4-methylphenol) were not used. The change with time of the quantity was examined. The result is shown in FIG.

Experimental Example 1-4
In Experimental Example 1-2, the same operation as in Experimental Example 1-2 was performed except that the catalyst (dioctyltin oxide) was not used, and the change in the amount of peroxide with time was examined. The result is shown in FIG.

  From the results shown in FIG. 1, in Experiments 1-1 to 1-2, the catalyst and the antioxidant are used in combination, so the peroxide contained in the alcohol having an ether group in a very short time. It can be seen that the content of can be reduced.

  On the other hand, in Experimental Examples 1-3 to 1-4, no catalyst or antioxidant is used, so that the content of peroxide contained in the alcohol having an ether group is 20 ppm or less. It can be seen that it takes a long time.

  From the above, when a catalyst and an antioxidant are used in combination with an alcohol having an ether group, the content of peroxide contained in the alcohol having an ether group is shortened as a synergistic effect of the combined use of both. It can be seen that the time can be reduced.

Experimental Example 2-1
In Example 1, the time-dependent change in the amount of peroxide produced (peroxide amount) in the system when tetrahydrofurfuryl alcohol was reacted with acrylic acid was examined. The result is shown in E of FIG.

Experimental Example 2-2
In Example 2, the time-dependent change of the amount of peroxide produced (peroxide amount) in the system when tetrahydrofurfuryl alcohol was reacted with methyl acrylate was examined. The result is shown in FIG.

Experimental Example 2-3
In Experimental Example 2-2, except that 2,6-di-t-butyl-4-methylphenol was not used, the same operation as in Experimental Example 2-2 was performed, and tetrahydrofurfuryl alcohol, methyl acrylate, The time-dependent change in the amount of peroxide produced (peroxide amount) in the system when was reacted. The result is shown in FIG.

  From the results shown in FIG. 2, in Experiments 2-1 and 2-2, the catalyst (dioctyltin oxide) and the antioxidant (methoquinone) are used in combination, so that the peroxide-decomposing alcohol and acrylic acid are used. Or it turns out that the production | generation of a peroxide can be suppressed effectively when making it react with methyl acrylate.

  On the other hand, in Experimental Example 2-3, 2,6-di-t-butyl-4-methylphenol is not used. Therefore, when the peroxide-decomposing alcohol and methyl acrylate are reacted with each other, It turns out that generation | occurrence | production cannot fully be suppressed.

  From the above results, when alcohol having an ether group is used in combination with a catalyst and 2,6-di-t-butyl-4-methylphenol as an antioxidant, peroxide-decomposing alcohol and acrylic acid or acrylic It turns out that it can suppress effectively that a peroxide produces | generates when it reacts with methyl acid.

  The (meth) acrylic acid ester obtained by the production method of the present invention is, for example, a curable resin that can be cured by a raw material such as a paint, an adhesive, a pressure-sensitive adhesive, a synthetic resin, a fiber, or a light having active energy such as ultraviolet rays. It can be suitably used as a reactive diluent.

In Experimental Examples 1-1 to 1-4, it is a figure which shows the time-dependent change of the peroxide amount in the alcohol which has an ether group. In Experimental example 2-1 to 2-3, it is a figure which shows the time-dependent change of the peroxide amount in the reaction system when the alcohol which has an ether group, and acrylic acid or methyl acrylate are made to react.

Claims (5)

  The alcohol having an ether group is heated to 50 to 150 ° C. in the presence of a catalyst and an antioxidant to decompose the peroxide, and then the alcohol having the ether group is used to produce a (meth) acrylic acid ester. A method for producing a (meth) acrylic acid ester, characterized by being used as a raw material.   The process according to claim 1, wherein the alcohol having an ether group is heated until the amount of peroxide contained in the alcohol having an ether group is 20 ppm or less.   The method according to claim 1 or 2, wherein after decomposing the peroxide, an alcohol having an ether group is reacted with (meth) acrylic acid or an alkyl ester thereof.   The oxygen-containing gas is blown into a mixture of an alcohol having an ether group and (meth) acrylic acid or an alkyl ester thereof when reacting the alcohol having an ether group with (meth) acrylic acid or an alkyl ester thereof. Manufacturing method.   The process according to claim 4, wherein an oxygen-containing gas is blown into a mixture of an alcohol having an ether group and (meth) acrylic acid or an alkyl ester thereof at a rate of 0.01 to 1 L / hr per mole of the alcohol having an ether group. .

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