JP2011046625A - Method for producing epoxy group-containing acrylate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a production method stably producing an epoxy group-containing acrylate at a low cost with improved productivity achieved by greatly improving its yield upon producing the same. <P>SOLUTION: The method for producing an epoxy group-containing acrylate comprising an acryloyl group and an epoxy group in its molecule by using acrylic acid and an epoxy compound comprising a halogen element, including a process of causing an alkali metal acrylate prepared by neutralizing acrylic acid by an alkali metal carbonate to react with an epoxy compound comprising a halogen element, is characterized in that the alkali metal carbonate is particulate matter wherein the ratio of the particles passing through a standard sieve of a nominal opening of 500 μm stipulated in JIS Z8801-1 is from 60 to 100 mass%, and the ratio of the particles passing through a standard sieve of a nominal opening of 32 μm stipulated in JIS Z8801-1 is from 0 to 90 mass%. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

The present invention relates to a method for producing an epoxy group-containing acrylic ester. More specifically, the present invention relates to a method for producing an epoxy group-containing acrylate ester useful as a reactive monomer having an epoxy ring.

(Meth) acrylic acid ester containing an epoxy group such as glycidyl (meth) acrylate is useful as a reactive monomer having an epoxy ring, paint, adhesive, pressure-sensitive adhesive, fiber modifier, dispersant, resist It is used in a wide range of fields as a monomer raw material for materials. Conventionally, glycidyl methacrylate (GMA) whose (meth) acryloyl group portion is methacryloyl has been widely available as a general-purpose product, and there are many patent documents relating to its production and purification. However, glycidyl acrylate (GA), which is acryloyl, has the advantage of high reactivity, but is hardly industrially or reagent-wise. In addition, only glycidyl methacrylate (GMA) that has been converted to methacryloyl can be found in patent documents. The reason that glycidyl acrylate (GA) is not used is that it is very irritating to the skin and is difficult to handle, and the stability of the compound is low, making synthesis and purification difficult.

Conventionally, glycidyl (meth) acrylate is generally produced by the following three methods. That is, (meth) acrylic acid and epichlorohydrin were reacted in the presence of a quaternary ammonium salt to obtain 3-chloro-2-hydroxypropyl ester of (meth) acrylic acid. Dehydrochlorination method (first method); Transesterification reaction of methyl (meth) acrylate and glycidol in the presence of a basic catalyst (second method); (meth) acrylic acid and alkali metal This is a method (third method) in which an alkali metal salt of (meth) acrylic acid is obtained by reaction and then reacted with epichlorohydrin in the presence of a quaternary ammonium salt to cause dechlorination alkali.

Among these, specifically, as the third method, Patent Document 1 is blown with oxygen-containing gas of (meth) acrylic acid and alkali metal carbonate / bicarbonate in an excessive amount of epichlorohydrin. After neutralizing to produce an alkali metal salt of (meth) acrylic acid, this is reacted with epichlorohydrin to synthesize glycidyl ester of (meth) acrylic acid, and epichlorohydrin is recovered after the reaction After cooling, an aqueous alkali hydroxide solution is added to separate the aqueous layer and the organic layer, a catalyst deactivator is added to the resulting organic layer, and then distilled and separated while blowing an oxygen-containing gas. It is disclosed. Further, in Patent Document 2, when producing glycidyl methacrylate by reacting sodium methacrylate and epichlorohydrin, the reaction solution containing sodium chloride generated after the reaction is washed with water and separated into oil and water. In this method, a glycidyl methacrylate is obtained by removing the by-product glycidol by extraction with water and then distilling the oil layer. Furthermore, Patent Document 3 includes a reaction product solution when glycidyl (meth) acrylate is produced by reacting an alkali metal salt of (meth) acrylic acid with epichlorohydrin in the presence of a catalyst. A method is disclosed in which an alcoholic impurity is reacted with an acid anhydride in the presence of a basic catalyst and then the reaction product solution is purified by distillation.

Japanese Patent Laid-Open No. 9-59268 (pages 2, 5-6) JP 55-85575 A (first page) Japanese Patent Laid-Open No. 11-302269 (2nd, 5-7 pages)

As described above, various methods for producing glycidyl (meth) acrylate are disclosed. However, what is manufactured in the conventional methods such as Patent Documents 1 to 3 is substantially glycidyl methacrylate, and specifically describes the production of glycidyl acrylate in which the (meth) acryloyl group portion becomes acryloyl. There is nothing to consider. Moreover, in the conventional production method, an epoxy group-containing acrylate ester having higher reactivity and lower stability is produced, even if the methacryloyl epoxy group-containing methacrylate ester can be obtained in a sufficient yield. In such a case, a sufficient yield could not be obtained. For example, in the first method, a lot of by-products are produced, and the purity is poor and the yield is low. In the second method, since a compound having an expensive epoxy group such as glycidol is used, there is room for improvement in terms of production cost, and the yield is low. Furthermore, even when the third method is used, in the technique of producing an epoxy group-containing (meth) acrylic acid ester, the yield is not sufficient only when methacryloyl becomes acryloyl, and as an industrial production method, There was room for ingenuity.

The present invention has been made in view of the above situation, and in producing an epoxy group-containing acrylic ester, productivity can be improved by greatly improving the yield, and the production can be stably performed at low cost. It is an object of the present invention to provide a manufacturing method that can be used.

The inventors of the present invention have made various studies on a method for producing an epoxy group-containing acrylic acid ester for which no effective method has been established so far, and reacts an alkali metal salt of acrylic acid with an epoxy compound having a halogen element. If it is a production method, it is an effective production method from the viewpoint of yield and cost reduction. On the other hand, when the reaction is carried out in the same manner as the conventional method for producing an epoxy group-containing methacrylic acid ester, acrylic acid reacts more than methacrylic acid. It was found that a sufficient yield could not be obtained because the reaction between acrylic acids proceeded or the product was decomposed due to its high properties. Thus, the epoxy group-containing acrylic acid ester has a specific problem that is not seen when obtaining an epoxy group-containing methacrylate ester in terms of the reaction yield. By newly determining that the particle size of the alkali metal carbonate used as the neutralizing agent in obtaining the product greatly contributes to the reaction yield of the epoxy group-containing acrylate ester as the target product, by defining the particle size It has been found that the reaction yield is significantly improved. That is, in the production of an epoxy group-containing acrylic acid ester, reacting an alkali metal salt of acrylic acid neutralized with an alkali metal carbonate having an average particle diameter in a specific range with an epoxy compound having a halogen element; As a result, it was conceived that an epoxy group-containing acrylic ester can be obtained in a high yield, and a problem in terms of yield peculiar to obtaining an epoxy group-containing acrylic ester is solved.

Further, in such a production method, the production of by-products is small, the purification process can be simplified and the number of processes involving removal of impurities can be reduced, and the raw materials are stable, so that the cost is low. We have found that it can be stably manufactured, and have come up with the idea that the above problems can be solved brilliantly. Furthermore, the present inventors have found that when the equivalent ratio of the epoxy compound having a halogen element used in the reaction is specified, the influence of the particle size of the neutralizing agent on the reaction yield appears more prominently. Has reached

As described above, the present invention makes it possible to improve the reaction yield by defining the particle size of the alkali metal carbonate used as the neutralizing agent. For example, the following may be presumed as factors affecting the above. That is, if the particle size of the alkali metal carbonate used as the neutralizing agent is set within a certain range, the acrylic acid is sufficiently neutralized, and the amount of acrylic acid remaining without being neutralized can be reduced. This is considered to be because the side reaction that seems to be caused by the sum of acrylic acid can be sufficiently suppressed.

That is, the present invention is a method for producing an epoxy group-containing acrylic ester having an acryloyl group and an epoxy group in one molecule using acrylic acid and an epoxy compound having a halogen element, and the production method comprises: A step of reacting an alkali metal salt of acrylic acid neutralized with an alkali metal carbonate with an epoxy compound having a halogen element, wherein the alkali metal carbonate has a nominal opening defined in JIS Z8801-1. A granular material in which the proportion of particles passing through a 500 μm standard sieve is 60 to 100% by mass and the proportion of particles passing through a standard sieve having a nominal aperture of 32 μm specified in JIS Z8801-1 is 0 to 90% by mass. This is a method for producing an epoxy group-containing acrylic ester.
The present invention is described in detail below.

The epoxy group-containing acrylic ester obtained by the production method of the present invention may be a compound having one or more acryloyl groups and one or more epoxy groups in one molecule, and one acryloyl group and one epoxy group are included. Each of these compounds may be a compound having two or more acryloyl groups and two or more epoxy groups. For example, it may be a diacrylate compound having two acryloyl groups or a diepoxy compound having two epoxy groups, and is not particularly limited. In addition, the compound which has one acryloyl group and one epoxy group can be used suitably for a coating material, an adhesive agent, an adhesive, a fiber modifier, a dispersing agent, a resist material use, for example, diacrylate, The diepoxy compound can be preferably used, for example, as a paint, a resist material or various coating agents.

The above production method includes a step of reacting an alkali metal salt of acrylic acid obtained by neutralizing acrylic acid with an alkali metal carbonate and an epoxy compound having a halogen element. Is not particularly limited. For example, after the above reaction step, the product is cooled as necessary, and then the target product and other components are removed by performing distillation or rectification step after removing the solvent after removing the precipitated salt. It is preferred to separate.

In the above production method, the alkali metal carbonate has a particle ratio of 60 to 100% by mass passing through a standard sieve having a nominal opening of 500 μm as defined in JIS Z8801-1 (2006), and JIS Z8801-1 (2006). The ratio of particles passing through a standard sieve having a nominal aperture of 32 μm specified in (year) is 0 to 90% by mass. If the ratio of particles passing through the standard sieve having a nominal aperture of 500 μm (that is, particles of 500 μm or less) is less than 60% by mass, the yield of the epoxy group-containing acrylate ester may not be increased. When the ratio of particles passing through the standard sieve having a nominal aperture of 32 μm (that is, particles of 32 μm or less) exceeds 90% by mass, the generated salt of acrylic acid absorbs water in the system, Since fluidity | liquidity falls, stirring becomes difficult and there exists a possibility that it cannot progress to the reaction process with the epoxy compound which has a halogen element. The ratio of the particles of 500 μm or less is preferably 65% by mass or more, and more preferably 70% by mass or more. Further, the ratio of the particles of 32 μm or less is preferably 80% by mass or less, more preferably 70% by mass or less, still more preferably 60% by mass or less, and particularly preferably 50% by mass or less.
The ratio of the particles is the ratio of particles passing when all of the alkali metal carbonates used for the neutralization reaction are passed through the standard sieves, that is, the total amount of the alkali metal carbonates is 100% by mass. It means the ratio of the above particles.

It does not specifically limit as an alkali metal which comprises the said alkali metal carbonate, For example, sodium, potassium, lithium etc. are mentioned, These 1 type (s) or 2 or more types can be used.

The alkali metal carbonate may be used in an amount sufficient to neutralize acrylic acid. For example, 0.5 mol or more is preferable with respect to 1 mol of acrylic acid. More preferably, it is 0.52 mol or more. Moreover, when there are many carbonates which are not used for neutralization reaction, since the removal process may become complicated, it is preferable to set it as 0.7 mol or less, for example, More preferably, it is 0.6 mol or less.

Although the specific form is not specifically limited as a neutralization process of acrylic acid by the said alkali metal carbonate, When the reactivity of acrylic acid is considered, acrylic acid is dripped with respect to alkali metal carbonate. It is suitable that it is the process of performing a neutralization reaction. By this, a side reaction can be suppressed more and the yield of an epoxy-group-containing acrylic acid ester can further be improved. Moreover, it is preferable to change a dripping speed | rate suitably according to a scale.

In the neutralization reaction, the reaction conditions are not particularly limited. For example, it is preferable to perform the neutralization reaction by setting the system temperature to 110 ° C. or lower. More preferably, it is 90 degrees C or less, More preferably, it is 70 degrees C or less. The lower limit of the temperature is preferably set to 20 ° C. or higher. More preferably, it is 25 degreeC or more, More preferably, it is 30 degreeC or more. The neutralization time is preferably 0.1 hour or longer, and preferably within 5 hours. The neutralization time is more preferably 0.5 hours or longer. Moreover, within 3 hours is preferable. By setting to such conditions, it becomes possible to neutralize acrylic acid more sufficiently while suppressing side reactions. The neutralization reaction may be performed under normal pressure, or may be performed under pressure or reduced pressure, and is not particularly limited.

The alkali metal salt of acrylic acid neutralized in this way is reacted with an epoxy compound having a halogen element. In this reaction step, one of these reaction raw materials may be used. Two or more kinds may be used in combination.
The epoxy compound having a halogen element is not particularly limited as long as the halogen group is substituted for a compound having an epoxy group. For example, a compound such as epihalohydrin, a substituent such as a methyl group or a phenyl group is included in these compounds. Are bonded, and epihalohydrin is more preferable.
Examples of the epihalohydrin include, for example, epichlorohydrin, epibromhydrin, epiiodohydrin, methyl epichlorohydrin, methyl epibromhydrin, methyl epiiohydrin, and the like, as well as a methyl group, Those having a substituent such as a phenyl group bonded thereto are preferred.

The amount of the epoxy compound having a halogen element used in the above reaction is preferably 12 mol or less with respect to 1 mol of the alkali metal salt of acrylic acid. By setting it within this range, the effect of the particle size of the neutralizing agent (alkali metal carbonate) used in the neutralization step on the reaction yield is remarkably exhibited. A group-containing acrylic ester can be obtained. In addition, the production method is also suitable in terms of reaction efficiency. Moreover, 3 mol or more is preferable from a viewpoint which advances reaction more fully, More preferably, it is 4 mol or more.

The above reaction is preferably carried out in the presence of a catalyst. By using a catalyst, reaction can be performed efficiently and the yield of the produced | generated epoxy-group-containing acrylic acid ester can be improved. Thus, the form in which the reaction step is performed in the presence of a catalyst is one of the preferred forms of the present invention.
The catalyst is not particularly limited, but is preferably a basic catalyst. In addition, it is preferable that an epoxy compound such as epichlorohydrin does not cause ring opening or polymerization, and examples of the organic base that is a basic catalyst include trimethylamine, triethylamine, tributylamine, triethanolamine, dimethylethanol. Amine, diethylethanolamine, tetramethylammonium chloride, trimethylethylammonium chloride, dimethyldiethylammonium chloride, methyltriethylammonium chloride, tetraethylammonium chloride, trimethylbenzylammonium chloride, triethylbenzylammonium chloride, tetramethylammonium hydroxide, tetraethylammonium = Quaternary ammonia such as hydroxide, tetrapropylammonium hydroxide Salt and the like. These catalysts may be used alone or in combination with a plurality of catalysts.

Among the above basic catalysts, quaternary ammonium salts are particularly preferable. Specific examples include tetramethylammonium chloride, trimethylethylammonium chloride, dimethyldiethylammonium chloride, methyltriethylammonium chloride, tetraethylammonium chloride, trimethylbenzylammonium chloride, triethylbenzylammonium chloride and the like. Of these, tetramethylammonium chloride, tetraethylammonium chloride, triethylbenzylammonium chloride, and trimethylbenzylammonium chloride are preferred. In addition, a quaternary ammonium salt may be used independently and may be used in combination of arbitrary 2 or more types.

The amount of the catalyst used is preferably 0.0001 part by weight or more with respect to 100 parts by weight of the total amount of the alkali metal salt of acrylic acid as the reaction raw material and the epoxy compound having a halogen element. More preferably, it is 0.0005 weight part or more, More preferably, it is 0.001 weight part or more, Most preferably, it is 0.002 weight part or more. Moreover, 3 weight part or less is suitable, More preferably, it is 1 weight part or less, More preferably, it is 0.5 weight part or less, Most preferably, it is 0.1 weight part or less.

The above reaction is also preferably performed in the presence of a stabilizer such as an antioxidant or a polymerization inhibitor. Thereby, decomposition | disassembly of the produced | generated epoxy-group-containing acrylic acid ester can be suppressed more, and the improvement of a yield can be aimed at further.
It does not specifically limit as said stabilizer, Usually, what is used as antioxidant, a polymerization inhibitor, etc. can be used. For example, phosphorus-based, N-oxyl-based, phenol-based, amine-based, sulfur-based, transition metal-based, and the like are preferable, and among them, phosphorus-based, N-oxyl-based, and phenol-based are preferable. In particular, the embodiment in which the reaction step is performed in the presence of an alkylphenol-based compound (polymerization inhibitor), or in the presence of a phosphorus-based antioxidant and / or an N-oxyl-based antioxidant is the present invention. It is a suitable form. In addition, these compounds may be used independently and may use 2 or more types together.

The alkylphenol compound is a compound having one or a plurality of aromatic rings, having only one hydroxyl group in one aromatic ring, and having an alkyl group in the aromatic ring. By carrying out the above reaction step in the presence of such an alkylphenol compound, the epoxy group-containing acrylate ester can be synthesized in a high yield, and the productivity can be greatly improved. Moreover, since productivity improves, cost reduction can also be achieved. This is considered to be due to the fact that the alkylphenolic compound can suppress the reaction between acrylic acids by temporarily trapping the radicals possessed by the alkali metal salt of acrylic acid. Here, for example, when an alkyldiphenol compound having two or more hydroxyl groups in one aromatic ring is used, there is a possibility that a sufficient yield cannot be obtained. Thus, the form in which the reaction step is performed in the presence of an alkylphenol compound is one of the preferred forms of the present invention. That is, it is preferable to react an alkali metal salt of acrylic acid with an epoxy compound using an alkylphenol compound as a polymerization inhibitor.
In addition, “having only one hydroxyl group in one aromatic ring” means that only one hydroxyl group is bonded to any carbon atom forming one aromatic ring.

In the alkylphenol compound, the aromatic ring having only one hydroxyl group preferably does not have an alkoxy group. In the case of an alkylphenol-based compound in which an alkoxy group is further bonded to an aromatic ring to which a hydroxyl group is bonded, there is a possibility that the effect of inhibiting polymerization is not sufficient. Examples of the alkoxy group include a methoxy group and an ethoxy group. If it is such a form, the yield of the epoxy-group-containing acrylic ester obtained by this invention can be improved more, and the effect of this invention can be acquired more fully.

The structure of the alkylphenol compound is not particularly limited as long as one or more alkyl groups are bonded to one aromatic ring. The alkyl group is not particularly limited, but is preferably an alkyl group having 1 to 10 carbon atoms, and may have a substituent.
Specific examples of the alkyl group include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, an octyl group, and the like, but in a chain form in which carbon atoms are linearly linked. Alternatively, it may be in a branched form. Moreover, cyclic | annular form (For example, cycloalkyl groups, such as a cyclohexyl group), may be sufficient. More preferably, it is an alkyl group having 1 to 5 carbon atoms such as a methyl group, an ethyl group, a propyl group, or a butyl group, and more preferably a methyl group or a butyl group.
The substituent bonded to the side chain of the alkyl group is preferably other than those having two or more hydroxyl groups in one aromatic ring, and may be an aromatic substituent such as a phenyl group.

The alkylphenol compound is particularly preferably one having one or a plurality of aromatic rings and having only one hydroxyl group in one aromatic ring, and having a substituent at the ortho position of the aromatic ring having a hydroxyl group. It is the form which has C1-C10 alkyl group which may be carried out. The alkylphenol-based compound in such a form can exhibit the effects of the present invention more sufficiently and can improve the yield. Moreover, it is preferable because it is easily available and has high stability.

Specific examples of the alkylphenol compounds include the following compounds.
2,2′-methylene-bis (4-methyl-6-tert-butylphenol) (for example, “ANTAGE W-400”, manufactured by Kawaguchi Chemical Co., Ltd.), 2,2′-methylene-bis (4-ethyl- 6-tert-butylphenol) (for example, “ANTAGE W-500”, manufactured by Kawaguchi Chemical Co., Ltd.), 1,3,5-tris- (3 ′, 5′-di-tert-butyl-4-hydroxybenzyl) Isocyanuric acid (for example, “Adekastab AO20”, manufactured by ADEKA Corporation), 1,1,3-tris- (2-methyl-4-hydroxy-5-tert-butylphenyl) butane (for example, “Adekastab AO30”, stock) Manufactured by ADEKA), 4,4-butylidene-bis- (3-methyl-6-tert-butylphenol) (for example, “ADK STAB AO40”, ADEKA Co., Ltd.), n-octadecyl-3- (3 ′, 5′-di-tert-butyl-4′-hydroxyphenyl) propionate (for example, “Adeka Stub AO50”, manufactured by ADEKA Corporation), tetrakis- (methylene -3- (3 ′, 5′-di-tert-butyl-4′-hydroxyphenyl) propionate) methane (for example, “ADK STAB AO60”, manufactured by ADEKA Corporation), tri-ethylene glycol-bis- [3- ( 3-tert-butyl-5-methyl-4-hydroxyphenyl) propionate (for example, “ADK STAB AO70” manufactured by ADEKA Corporation), 3,9-bis [1,1-di-methyl-2- {β- ( 3-tert-butyl-4-hydroxy-5-methylphenyl) propionyloxy} ethyl] -2,4,8,1 -Tetraoxaspiro [5,5] undecane (for example, “Adeka Stab AO80”, manufactured by ADEKA Corporation), 1,3,5-trimethyl-2,4,6-tris- (3,5-di-tert-butyl -4-hydroxybenzyl) benzene (for example, “ADK STAB AO330”, manufactured by ADEKA Corporation), 2,6-di-tert-butyl-4-methylphenol (for example, “SUMILIZER BHT”, manufactured by Sumitomo Chemical Co., Ltd.), Di (α-methylbenzyl) phenol (for example, “SUMILIZER S”, manufactured by Sumitomo Chemical Co., Ltd.), N, N′-bis-3- (3 ′, 5′-di-tert-butyl-4-hydroxyphenyl) Propionyl hexamethylenediamine (for example, “IRGANOX 1098”, manufactured by Toyota Tsusho Corporation), 1,3,5-trimethyl- , 4,6-tris - (3,5-di -tert- butyl-4-hydroxybenzyl) benzene (e.g., "IRGANOX 1330", manufactured by Toyota Tsusho Corporation) and the like.

In the above reaction, the amount of the alkylphenol compound present in the reaction system is 0.001 part by weight or more with respect to 100 parts by weight of the total amount of the alkali metal salt of acrylic acid and the epoxy compound having a halogen element. preferable. By including the alkylphenol compound in such a range, the reaction can be more sufficiently progressed, and the yield can be further improved. More preferably, it is 0.01 weight part or more, More preferably, it is 0.05 weight part or more. Moreover, 5 weight part or less is preferable, More preferably, it is 3 weight part or less, More preferably, it is 2 weight part or less.

The phosphorus-based antioxidant is not particularly limited, and a commonly used one may be used. For example, the following compounds can be used.
Triphenylphosphine; triphenylphosphite, diphenylisodecylphosphite, phenyldiisodecylphosphite, tris (nonylphenyl) phosphite, tris (dinonylphenyl) phosphite, tris (2,4-di-tert-butylphenyl) Phosphite, tris (2-tert-butyl-4-methylphenyl) phosphite, tris (cyclohexylphenyl) phosphite, 2,2-methylenebis (4,6-di-tert-butylphenyl) octyl phosphite, 9, 10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide, 10- (3,5-di-tert-butyl-4-hydroxybenzyl) -9,10-dihydro-9-oxa-10-phos Faphenanthrene-10-oxa Mono-phosphite compounds such as 10-decyloxy-9,10-dihydro-9-oxa-10-phosphaphenanthrene; 4,4′-butylidene-bis (3-methyl-6-tert-butylphenyl-di -Tridecyl phosphite), 4,4'-isopropylidene-bis (phenyl-di-alkyl (C12-C15) phosphite), 4,4'-isopropylidene-bis (diphenylmonoalkyl (C12-C15) phos Phyto), 1,1,3-tris (2-methyl-4-di-tridecylphosphite-5-tert-butylphenyl) butane, tetrakis (2,4-di-tert-butylphenyl) -4,4 '-Biphenylenediphosphite, cyclic neopentanetetraylbis (octadecyl phosphite), cyclic neope Tantetrayl bis (isodecyl phosphite), cyclic neopentane tetrayl bis (nonylphenyl phosphite), cyclic neopentane tetrayl bis (2,4-di-tert-butylphenyl phosphite), cyclic neopentane Diphosphite compounds such as tetraylbis (2,4-dimethylphenylphosphite) and cyclic neopentanetetraylbis (2,6-di-tert-butylphenylphosphite).
Among these, triphenylphosphine and monophosphite compounds are suitable. . As the monophosphite compound, tris (nonylphenyl) phosphite, tris (dinonylphenyl) phosphite, tris (2,4-di-tert-butylphenyl) phosphite and the like are particularly preferable.

It does not specifically limit as said N-oxyl type antioxidant, What is necessary is just to use what is used normally. For example, the following compounds can be used.
2,2,6,6-tetramethyl-4-hydroxypiperidine-N-oxyl (4H-TEMPO), 2,2,6,6-tetramethyl-4-benzoyloxypiperidine-N-oxyl, 4-acetylamino -2,2,6,6-tetramethylpiperidine-N-oxyl, bis (2,2,6,6-tetramethyl-N-oxylpiperidyl) succinate, 1-oxyl-2,2,6,6-tetra Methyl-4- (2,3-dihydroxypropoxy) piperidine, 1-oxyl-2,2,6,6-tetramethyl-4-glycidyloxypiperidine, bis (2,2,6,6-tetramethylpiperidine sebacate) Peridinoxy) (trade name: EC3314A, manufactured by Nalco Japan Co., Ltd.), compounds having an ester bond, and the like.

The reaction conditions in the above reaction may be appropriately selected depending on the type and amount of raw materials, stabilizers, products, etc., but for example, the reaction temperature is preferably set to 120 ° C. or lower. Thereby, side reactions, such as decomposition | disassembly of the produced | generated epoxy-group-containing acrylic acid ester, are fully suppressed, and it becomes possible to obtain a higher yield. More preferably, it is 110 degrees C or less, More preferably, it is 95 degrees C or less. Moreover, it is suitable to set it as 40 degreeC or more from a viewpoint of making reaction progress more fully. More preferably, it is 45 degreeC or more, More preferably, it is 50 degreeC or more.

The reaction time may be appropriately selected depending on the type and amount of raw materials, stabilizers, products and the like, but is preferably 0.1 hours or longer, for example, and preferably within 10 hours. If the reaction time is too short, the reaction may not proceed and a sufficient yield may not be obtained. If the reaction time is too long, decomposition of the produced epoxy group-containing acrylate ester may be sufficient. There is a risk that a high yield cannot be obtained. The reaction time is more preferably 0.5 hours or more, and still more preferably 1 hour or more. Moreover, within 7 hours is more preferable, and within 5 hours is still more preferable.

The above reaction may be performed under normal pressure, may be performed under pressure, or under reduced pressure, and is not particularly limited, but is performed under normal pressure from the viewpoint of simplifying the production method. It is preferable. In the above reaction, it is preferable that the water concentration in the reaction system is low in order to sufficiently suppress the formation of by-products. However, in order to sufficiently remove the water present in the reaction system, the reaction is performed under reduced pressure. It is also preferable to do this.
The atmosphere in which the above reaction is performed is not particularly limited. For example, the polymerization inhibitor exhibits its effectiveness when oxygen molecules are present. In addition, since too many oxygen molecules belong to the explosion range, it is preferable to set the molecular oxygen concentration to an appropriate concentration. From this viewpoint, it is preferable to set the molecular oxygen concentration in the reaction gas phase part to 0.01% by volume (volume%) or more and 10% by volume or less. This range of molecular oxygen concentration is effective from the viewpoints of yield, polymerization inhibition, explosion avoidance, and economy. More preferably, it is 0.02 volume% or more, More preferably, it is 0.05 volume% or more, More preferably, it is 9 volume% or less, More preferably, it is 8 volume% or less. The molecular oxygen concentration is set by supplying a gas containing molecular oxygen such as molecular oxygen or air and an inert gas such as nitrogen or argon separately to the reactor or by mixing them in advance. It is done by doing.

In the present invention, as described above, by specifying the particle size of the alkali metal carbonate as the neutralizing agent, acrylic acid cannot be obtained in a sufficient yield by the same method as that for producing a conventional methacrylic ester. Even in the case of using, it is possible to increase the yield of the target epoxy group-containing acrylic ester. Therefore, the yield of the epoxy group-containing acrylic ester obtained by the reaction step can be set to 40 mol% or more, for example, with respect to 100 mol% of acrylic acid used in the reaction. Preferably it is 45 mol% or more, More preferably, it is 50 mol% or more, More preferably, it is 55 mol% or more.

The method for producing an epoxy group-containing acrylate ester of the present invention has the above-described structure, and greatly improves the yield which was extremely low when produced in the same manner as the conventional methacrylic ester production methods. This is an industrially extremely useful technique. According to such a manufacturing method, productivity can be improved, and cost can be reduced. In addition, the epoxy group-containing acrylic ester obtained in the present invention is more reactive than the epoxy group-containing methacrylic ester, and is particularly useful as a reactive monomer when synthesizing a polymer. It can be suitably used for agent raw materials, paint raw materials, for molding resin copolymerization, acrylic fibers, acrylic rubber and the like.

The present invention will be described in more detail with reference to the following examples. However, the present invention is not limited to these examples. Unless otherwise specified, “part” means “part by weight” and “%” means “% by mass”.

Example 1
Table 5 shows epichlorohydrin (ECH) 353 g (3.8 mol) in a five-necked flask with an internal volume of 500 ml equipped with a gas inlet tube, thermometer, stirrer and cooler having a decanter for oil-water separation. Potassium carbonate B 63.3 g (0.46 mol), triphenylphosphine 0.4 g, 2,6-di-tert-butyl-4-methylphenol 0.4 g, 1,3,5-tris- (3 ′ , 5′-di-tert-butyl-4-hydroxybenzyl) isocyanuric acid 0.4 g and bis (2,2,6,6-tetramethylpiperidinoxy) sebacic acid 0.4 g were added to the reaction solution. While blowing an oxygen / nitrogen mixed gas, the pressure was reduced to 60 Torr (1 Torr = 133.322 Pa), and the temperature was raised to 50 ° C. at which ECH boils. The distillate was separated into an aqueous phase and an ECH phase with a decanter, and 55 g (0.76 mol) of acrylic acid was added dropwise over about 1 hour while the lower ECH phase was refluxed into the flask. After completion of the dropwise addition, the mixture was further refluxed for 20 minutes. Then, 0.25 g of tetramethylammonium chloride was added, the temperature was raised to an internal pressure of 300 Torr and 92 ° C., and the reaction was performed for 4 hours while refluxing the lower ECH phase. After cooling to room temperature, filtration was performed to remove the slurry composed of potassium chloride and the like. About the obtained glycidyl acrylate (this is called "crude GA"), the reaction yield was calculated | required on the basis of acrylic acid (The charging amount of acrylic acid shall be 100 mol%.). The results are shown in Table 2.
The obtained reaction solution (crude GA) was washed with water of 1/3 the amount of crude GA, and then epichlorohydrin was distilled off at 150 to 30 Torr, and further distilled at 15 Torr to obtain a crude GA solution. It was. Further, the crude GA solution was rectified to obtain an initial distillation and a main distillation.

Examples 2, 5-6, Comparative Example 1
Except for replacing potassium carbonate with potassium carbonate A (Comparative Example 1), potassium carbonate C (Example 2), potassium carbonate D (Example 5) and potassium carbonate E (Example 6) shown in Table 1, respectively. In the same manner as in Example 1, glycidyl acrylate (crude GA) was obtained. The reaction yield of crude GA based on acrylic acid is shown in Table 2. Thereafter, a crude GA solution was obtained in the same manner as in Example 1, and then the crude GA solution was further rectified to obtain an initial distillation and a main distillation.

Examples 3 and 4
Acrylic acid was used in the same manner as in Example 2 except that the amount of epichlorohydrin used was 8 mol (Example 3) and 10 mol (Example 4) per mol of acrylic acid. Glycidyl (crude GA) was obtained. The reaction yield of crude GA based on acrylic acid is shown in Table 2. Thereafter, a crude GA solution was obtained in the same manner as in Example 2, and then the crude GA solution was further rectified to obtain an initial distillation and a main distillation.

Example 7
Example 1 except that potassium carbonate was replaced with potassium carbonate F shown in Table 1 and that 3 mol of epichlorohydrin was further added to 1 mol of acrylic acid after the addition of acrylic acid. Thus, glycidyl acrylate (crude GA) was obtained. The reaction yield of crude GA based on acrylic acid is shown in Table 2. Thereafter, a crude GA solution was obtained in the same manner as in Example 1, and then the crude GA solution was further rectified to obtain an initial distillation and a main distillation.
In addition, epichlorohydrin (3 mol amount with respect to 1 mol of acrylic acid) was further added in Example 7 because the fluidity of the bottom liquid was lost by the potassium acrylate produced in the neutralization step, and stirring was difficult. It is because it became. Therefore, the total amount of epichlorohydrin used in Example 7 is 8 moles (= 5 moles + 3 moles) per mole of acrylic acid.

Comparative Example 2
In the same manner as in Example 1, except that potassium carbonate was replaced with potassium carbonate G shown in Table 1 and that the amount of epichlorohydrin used was 9 mol relative to 1 mol of acrylic acid, acrylic was used. An attempt was made to obtain glycidyl acid (crude GA), but at the end of the neutralization process, the fluidity of the bottom was lowered and the reaction could not be carried out.

Comparative Example 3
Glycidyl methacrylate (crude GMA) was obtained in the same manner as in Example 1 except that potassium carbonate was replaced with potassium carbonate A shown in Table 1, and 55 g of acrylic acid was replaced with 65.7 g of methacrylic acid. It was. Table 2 shows the reaction yield of crude GMA based on methacrylic acid.

Comparative Example 4
Glycidyl methacrylate (crude GMA) was obtained in the same manner as in Example 1 except that potassium carbonate was replaced with potassium carbonate E shown in Table 1, and 55 g of acrylic acid was replaced with 65.7 g of methacrylic acid. It was. Table 2 shows the reaction yield of crude GMA based on methacrylic acid.

Reference example 1
0.4 g of triphenylphosphine, 0.4 g of 2,6-di-tert-butyl-4-methylphenol, 1,3,5-tris- (3 ′, 5′-di-tert-butyl-4-hydroxybenzyl ) Same as Example 3 except that 0.4 g of phenothiazine was used instead of 0.4 g of isocyanuric acid and 0.4 g of bis (2,2,6,6-tetramethylpiperidinoxy) sebacate Thus, glycidyl acrylate (crude GA) was obtained. The reaction yield of crude GA based on acrylic acid is shown in Table 2.

The charge ratio (mol) in Table 2 means the amount (mol) of epichlorohydrin (ECH) and potassium carbonate when acrylic acid or methacrylic acid is 1 mol.
In Table 2, AA means acrylic acid, and MAA means methacrylic acid.

From the examples and comparative examples described above, it was found that the significance of specifying the particle size of the alkali metal carbonate used for neutralization of acrylic acid can be said as follows. That is, as the alkali metal carbonate, by using a granular material in which the proportion of particles of 500 μm or less is 60 to 100% by mass and the proportion of particles of 32 μm or less is 0 to 90% by mass, It has been found that it has an advantageous effect on the yield and is significant.

Regarding the technical significance that the ratio of particles of 500 μm or less (particles passing through a nominal opening of 500 μm as defined in JIS Z8801-1 (2006)) is 60% by mass or more, Example 1 (potassium carbonate B) Then, it is an example which is slightly higher than the lower limit (60% by mass) at 67.7% by mass, and it is clear when compared with Comparative Example 1 (potassium carbonate A, 58.9% by mass) which is lower than the lower limit. In Example 1, the yield was 58.1 mol%, while in Comparative Example 1, it was remarkably low at 38.7 mol%. Moreover, about the technical significance that the ratio of particles of 32 μm or less (particles passing through a nominal opening of 32 μm defined in JIS Z8801-1 (2006)) is 90% by mass or less, Examples 1 to 7 In contrast to the fact that the reaction could be carried out, in Comparative Example 2 (potassium carbonate G, 100% by mass), the fluidity of the bottom was low and it was apparent that the reaction could not be carried out.

Further, from the results of Comparative Examples 3 and 4, when trying to obtain an epoxy group-containing methacrylic acid ester using methacrylic acid and an epoxy compound having a halogen element instead of acrylic acid, the alkali metal that is a neutralizing agent is used. It can be seen that high yields are obtained regardless of the particle size of the carbonate. From this, it can be said that the problem that a high yield cannot be obtained in the first place is a problem peculiar to the case of using acrylic acid, and that a high yield can be achieved by specifying the particle size of the alkali metal carbonate. It turned out that the effect of this invention is an effect peculiar when obtaining an epoxy-group-containing acrylate ester using acrylic acid.
Furthermore, from the comparison result between Example 3 and Reference Example 1, it was found that the synthesis of the epoxy group-containing acrylate ester can be performed in a higher yield by carrying out the reaction in the presence of the alkylphenol compound.

Claims (3)

A method for producing an epoxy group-containing acrylic ester having an acryloyl group and an epoxy group in one molecule using acrylic acid and an epoxy compound having a halogen element,
The production method includes a step of reacting an alkali metal salt of acrylic acid neutralized with an alkali metal carbonate and an epoxy compound having a halogen element,
The alkali metal carbonate is a standard sieve having a particle size of 60 to 100% by mass passing through a standard sieve having a nominal opening of 500 μm specified in JIS Z8801-1 and a nominal opening of 32 μm specified in JIS Z8801-1. A method for producing an epoxy group-containing acrylate ester, characterized in that the proportion of particles passing through is a granular material having a ratio of 0 to 90% by mass. The method for producing an epoxy group-containing acrylic ester according to claim 1, wherein the reaction step is performed in the presence of an alkylphenol compound. The method for producing an epoxy group-containing acrylic ester according to claim 1 or 2, wherein the reaction step is performed in the presence of a catalyst.