JPH09241216A - Purification of acrylic ester derivative - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a purified acrylic ester derivative useful as a monomer for urethane crosslinking or melamine crosslinking. SOLUTION: This purified acrylic ester derivative, for example, methyl 2-(2- hydroxyethoxy)methyl acrylate, is obtained by washing an acrylic ester derivative which is expressed by the formula (R1 and R2 are each H of an organic residue; R3 is an organic residue; (n) is a positive number of 1-3; (m) is a positive number of 1-100) and is contaminated with nonpolymerizable alcohol(s) as impurities with a cleaning agent containing at least water (containing such an organic solvent as to be subject to two layer separation with water and >=7 in solubility parameter). In this case, it is preferable that the amounts of the water and organic solvent to be used are 0.001-100 and 0-100 in terms of weight ratio to the derivative.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a method for purifying an acrylic acid ester derivative.

[0002]

2. Description of the Related Art It is known that polyethylene glycol is present as an impurity in polyethylene glycol mono (meth) acrylate obtained by adding ethylene oxide to (meth) acrylic acid. The cause of the presence of the impurities in the polyethylene glycol mono (meth) acrylate is the raw material (meth).
Ethylene oxide added to water in acrylic acid,
When ethylene oxide is added to the (meth) acrylic acid ester, as a side reaction, a transesterification reaction occurs between the polyethylene glycol mono (meth) acrylates, and polyethylene glycol and polyethylene glycol di (meth) acrylate are produced. Can be mentioned.

[0003]

Therefore, as a result of various investigations by the inventors of the present invention, the above-mentioned (meta) was obtained even in the case of producing an acrylate derivative by adding a cyclic ether to an α-hydroxyalkyl acrylate. ) It was found that polyalkylene glycol such as polyethylene glycol was produced under the influence of water in the raw material as in the case of adding ethylene oxide to acrylic acid. Further, a transesterification reaction occurs between the hydroxyl group and the ester group of the α-hydroxyalkyl acrylic acid ester or acrylic acid ester derivative,
A dimer linked by an ester bond is obtained as a by-product, and an alcohol such as ethanol is removed from the α-hydroxyalkyl acrylic acid ester or acrylic acid ester derivative, and a reaction in which a cyclic ether is added to this alcohol occurs. I understood. Furthermore, the α-hydroxyalkyl acrylic acid ester causes a dehydration reaction between two molecules to generate an ether dimer and water. Cyclic ether is also added to this water to produce polyethylene glycol. The alcohol produced by these reactions is a non-polymerizable impurity.

Generally, a compound having a polymerizable vinyl group and a hydroxyl group in the same molecule is used as a urethane crosslinking monomer or a melamine crosslinking monomer. However, when the above compound is reacted with, for example, an isocyanate compound and the reaction product is used as a urethane acrylate oligomer, when a non-polymerizable alcohol is contained as an impurity, the non-polymerizable alcohol also reacts with the isocyanate compound. . Therefore, in order to increase the yield of the target product, it is necessary to increase the amount of the isocyanate compound added.

Therefore, even when the above acrylic ester derivative is used as a urethane acrylate oligomer, if non-polymerizable alcohol is present as an impurity, it is necessary to increase the amount of the isocyanate compound added.

Further, when the above acrylic acid ester derivative is polymerized and the obtained acrylic acid ester polymer is reacted with an isocyanate compound to crosslink, addition of an isocyanate compound is necessary in order to carry out sufficient crosslinking. It is desirable to increase the amount or to purify the acrylic ester polymer. This is because the hydroxyl group of the non-polymerizable alcohol, which is an impurity, is more reactive than the hydroxyl group of the side chain of the acrylic acid-based polymer. Therefore, if the acrylic acid derivative contains a non-polymerizable alcohol, there is a possibility that the crosslinking reaction cannot be carried out at a low cost. Therefore, in order to efficiently carry out urethane crosslinking and melamine crosslinking, it is desirable to remove the non-polymerizable alcohol from the acrylic acid derivative. That is, an object of the present invention is to provide a method for purifying an acrylic acid ester derivative containing a non-polymerizable alcohol as an impurity.

[0007]

Means for Solving the Problems The inventors of the present application have conducted extensive studies to achieve the above object, and as a result, there is a difference in solubility between water and a solvent between the non-polymerizable alcohol and the acrylic ester derivative. The acrylic ester derivative containing the non-polymerizable alcohol as an impurity is found to be able to remove the non-polymerizable alcohol from the acrylic ester derivative by washing with water or a mixed system of water and a specific solvent. The present invention has been completed.

That is, the method for purifying an acrylic acid ester derivative according to claim 1 of the present invention is directed to the general formula (1) containing a non-polymerizable alcohol as an impurity.

[0009]

Embedded image

(In the formula, R ₁ and R ₂ each independently represent a hydrogen atom or an organic residue, R ₃ represents an organic residue,
n represents a positive number of 1 to 3 and m represents a positive number of 1 to 10), and the acrylic ester derivative represented by the formula is washed with a detergent containing at least water.

The method for purifying an acrylic acid ester derivative according to a second aspect of the present invention is the method for purifying an acrylic acid ester derivative according to the first aspect, wherein the amount of water used with respect to the acrylic acid ester derivative is a weight ratio. 0.001 ~
It is characterized by being in the range of 100.

The method for purifying an acrylic acid ester derivative according to a third aspect of the present invention is the method for purifying an acrylic acid ester derivative according to the first or second aspect, wherein the cleaning agent is an organic solvent that separates from water into two layers. It is further characterized in that the organic solvent further contains a solubility parameter of 7 or more.

The method for purifying an acrylic acid ester derivative according to a fourth aspect of the present invention is the method for purifying an acrylic acid ester derivative according to the third aspect, wherein the amount of the organic solvent used relative to the acrylic acid ester derivative is a weight ratio. 0
It is characterized by exceeding 100 and below 100.

As described above, according to the present invention, an acrylic acid ester derivative containing a non-polymerizable alcohol as an impurity is washed with a cleaning agent containing at least water to remove the acrylic acid ester derivative from the non-polymerizable alcohol. Can be extracted into the aqueous layer and removed. This makes it possible to obtain an acrylate derivative that can reduce impurities and can efficiently perform urethane crosslinking and melamine crosslinking.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below in detail. The acrylic ester derivative according to the present invention has the general formula (1)

[0016]

Embedded image

(In the formula, R ₁ and R ₂ each independently represent a hydrogen atom or an organic residue, R ₃ represents an organic residue,
n represents a positive number of 1 to 3 and m represents a positive number of 1 to 10). For example, a cyclic ether compound is added to a corresponding α-hydroxyalkyl acrylate ester by a known method. It is obtained by doing.

The above acrylic ester derivative is represented by the following formula:
The substituents represented by R ₁ and R ₂ are each independently composed of a hydrogen atom or an organic residue, the substituent represented by R ₃ is composed of an organic residue, and the repeating unit represented by n is 1 ~ Represents a positive number of 3 and the repeating unit represented by m is 1
A compound that represents a positive number of -10. And, a portion derived from the cyclic ether compound, that is, —CH ₂ (CH
Repeating structure of oxyalkylene groups represented by R _{2) n} O-has the following structure. That is, the substituent represented by R ₂ may be independently composed of a hydrogen atom or an organic residue for each oxyalkylene group, and these oxyalkylene groups are bonded to each other in a block or random manner. Good.

As the above-mentioned acrylic ester derivative,
Specifically, for example, methyl-2- (2-hydroxyethoxy) methyl acrylate, ethyl-2- (2-hydroxyethoxy) methyl acrylate, butyl-2- (2-hydroxyethoxy) methyl acrylate, methyl-2- 〔2- (2-
Hydroxyethoxy) ethoxy] methyl acrylate,
Ethyl-2- [2- (2-hydroxyethoxy) ethoxy] methyl acrylate, butyl-2- [2- (2-hydroxyethoxy) ethoxy] methyl acrylate, methyl-2- (ω
-Hydroxypolyethyleneglycoxy) methyl acrylate, ethyl-2- (ω-hydroxypolyethyleneglycoxy) methyl acrylate, butyl-2- (ω-hydroxypolyethyleneglycoxy) methylacrylate, 2-ethylhexyl-2- (ω-hydroxypolyethylene Glyoxy) methyl acrylate and other α-hydroxyalkyl acrylate ethylene oxide adducts; methyl-2- (2-hydroxypropoxy) methyl acrylate,
Ethyl-2- (2-hydroxypropoxy) methyl acrylate, butyl-2- (2-hydroxypropoxy) methyl acrylate, methyl-2- [2- (2-hydroxypropoxy) propoxy] methyl acrylate, ethyl-2- [2
-(2-Hydroxypropoxy) propoxy] methyl acrylate, butyl-2- [2- (2-hydroxypropoxy) propoxy] methyl acrylate, methyl-2- (ω-hydroxypolypropyleneglycoxy) methyl acrylate, ethyl-2- ( ω-hydroxypolypropyleneglycoxy) methyl acrylate, butyl-2- (ω-hydroxypolypropyleneglycoxy) methyl acrylate, 2-
Propylene oxide adducts such as ethylhexyl-2- (ω-hydroxypolypropyleneglycoxy) methyl acrylate; alkylene oxides such as butylene oxide to α-hydroxymethyl acrylate, tetrahydrofuran compounds, allyl glycidyl ether, phenyl glycidyl ether, Examples thereof include adducts of alkyl glycidyl ether compounds such as epichlorohydrin. Among these acrylic acid ester derivatives, ethylene oxide adducts and propylene oxide adducts are particularly preferably used.

The above acrylic ester derivative can be easily homopolymerized or copolymerized with other polymerizable monomers in the presence of heat, ultraviolet rays, ionizing radiation, radical polymerization initiators and the like. Then, the acrylic acid ester derivative and the polymer thereof, like other compounds having a polymerizable vinyl group and a hydroxyl group in the same molecule, adhesion improver of the paint, urethane crosslinking monomer, melamine crosslinking monomer, paint,
Adhesives, surfactants, detergent builders, plasticizers, solid electrolytes, antistatic monomers, antifog agents, flocculants, dyeability improvers,
It can be suitably used as a fiber modifier, a fiber processing agent, a wood size stabilizer, and the like.

However, the amount of the above-mentioned acrylic ester derivative is small due to the side reaction during the reaction.
Contains multiple impurities. Among the above impurities, the non-polymerizable alcohol causes a side reaction different from the intended reaction when the hydroxyl group of the acrylic ester derivative or its polymer is reacted with isocyanate or the like.

According to the purification method of the present invention, the acrylic acid ester derivative containing the non-polymerizable alcohol, that is, the acrylic acid ester derivative before purification (hereinafter referred to as a crude acrylic acid ester derivative) contains at least water. By washing with a detergent, the non-polymerizable alcohol can be extracted and removed from the acrylic ester derivative in the aqueous layer.

The non-polymerizable alcohol removed in the present invention is a non-polymerizable hydroxyl group-containing compound such as polyalkylene glycol or polyalkylene glycol monoalkyl ether. Specific examples of the polyalkylene glycol include glycols such as polyethylene glycol, polypropylene glycol, and polybutylene glycol; and compounds in which an alkyl glycidyl ether is added to water.

The polyalkylene glycol monoalkyl ether is a reaction product of an alkyl monoglycol ether of an alkyl alcohol and a glycol, or an alkyl alcohol and an alkyl glycidyl ether, and specifically, for example, polyethylene glycol. Monomethyl ether, polyethylene glycol monoethyl ether, polyethylene glycol monobutyl ether,
Polyethylene glycol monoalkyl ethers such as polyethylene glycol mono-2-ethylhexyl ether;
Polypropylene glycol monomethyl ether, polypropylene glycol monoethyl ether, polypropylene glycol monobutyl ether, polypropylene glycol mono-2-ethylhexyl ether and other polypropylene glycol monoalkyl ethers; polybutylene glycol monomethyl ether, polybutylene glycol monoethyl ether, polybutylene glycol monobutyl ether , Polybutylene glycol mono-2-ethylhexyl ethers and the like.

In the present invention, the cleaning agent used for cleaning the crude acrylic acid ester derivative is a cleaning agent containing at least water, and is water or a mixed solution of water and an organic solvent which separates water into two layers. Can be used.

The amount of water used for washing the crude acrylic ester derivative, that is, the amount of water contained in the detergent, is the same as that of the detergent even when only water is used as the detergent. Even in the case of using water and a mixed solution of water and an organic solvent that separates into two layers, the weight ratio to the crude acrylic ester derivative is preferably in the range of 0.001 to 100, and more preferably in the range of 0.01 to 10. . If the amount of water used relative to the crude acrylic acid ester derivative is less than 0.001 in weight ratio, the removal efficiency of the non-polymerizable alcohol becomes poor, which is not preferable. On the other hand, the amount of water used in the crude acrylic ester derivative is 1 by weight.
If it is more than 00, the yield and productivity of the acrylic acid ester derivative after purification are lowered, which is not preferable.

The organic solvent used when the cleaning agent contains an organic solvent is not particularly limited as long as it is an organic solvent that is insoluble in water, but a solvent having a solubility parameter of 7 or more is preferable, and the solubility parameter is A solvent having a solubility parameter of 8.5 or more is more preferable, and a solvent having a solubility parameter of 8.5 or more is particularly preferable. If the dissolution parameter is less than 7, the flammability is high and the handling becomes complicated, which is not preferable.

The above dissolution parameter [δ] (unit: (cal / c
m ³ ) ^1/2 ) is a measure of solubility,

[0029]

[Equation 1]

(Wherein V represents a molar volume (cm ³ / mol),
ΔH represents the heat of vaporization (cal / mol), R represents the gas constant,
T represents absolute temperature (K)).

The organic solvent having a solubility parameter of 7 or more is not particularly limited, but specifically,
For example, hexane (solubility parameter 7.3: in the following compounds, the values in the parentheses () indicate solubility parameter values), aliphatic hydrocarbons such as cyclohexane (8.2) and methylcyclohexane (7.8); benzene (9.2), Aromatic hydrocarbons such as toluene (8.9) and xylene (8.8); Acetates such as ethyl acetate (9.1) and butyl acetate (8.5); Propionates such as ethyl propionate (8.4), methyl ethyl ketone (9.3), methyl Examples include ketones such as propyl ketone (8.7) and methyl isobutyl ketone (8.4); higher alcohols such as n-heptanol (10.6) and n-octanol (10.3). Among these organic solvents, solvents having a solubility parameter of 8.5 or more, for example, aromatic hydrocarbons such as benzene, toluene, xylene, and acetic acid esters such as ethyl acetate and butyl acetate have good solubility of the acrylic ester derivative, Particularly preferred. When the cleaning agent contains the organic solvent in addition to water, there is an advantage that the liquid separating property is improved and the productivity is improved.

The amount of the organic solvent used in washing the crude acrylic acid ester derivative, that is, in the case of using water and a mixed solution of water and an organic solvent for separating two layers as the detergent, The amount of the organic solvent contained is preferably more than 0 and 100 or less, and more preferably more than 0 and 10 or less by weight ratio with respect to the crude acrylic ester derivative. If the amount of the organic solvent used with respect to the crude acrylic acid ester derivative exceeds 100 by weight, the productivity is lowered, which is not preferable.

The washing method for washing the crude acrylic acid ester derivative is not particularly limited, and various conventionally known methods can be used. As the washing method, for example, an effective method such as stirring or line mixing may be used, and after standing to separate the two layers, water containing an organic solvent layer which is an acrylic ester derivative layer and a non-polymerizable alcohol is used. By separating the layer, the non-polymerizable alcohol can be extracted and removed from the crude acrylic acid ester derivative.

When the removal of the non-polymerizable alcohol is not sufficient, a cleaning agent may be further added for cleaning. The number of times of washing is not particularly limited and may be repeated until the effect is sufficiently exhibited.

After removing the non-polymerizable alcohol, the obtained acrylic acid ester derivative can be directly used for various purposes. However, the acrylic ester derivative may contain a small amount of an organic solvent or water used for washing. Therefore, the residual organic solvent or water may be removed after washing depending on the application.

The removal method for removing the organic solvent and water is not particularly limited, and various conventionally known methods can be used. Examples of the removal method include a method by evaporation and distillation, and a method of blowing a gas that has no risk of explosion. The used organic solvent can be recovered and reused.

Further, the above acrylic ester derivative is
Since it contains a vinyl group in the molecule, it has the property of being easily polymerized. Therefore, it is preferable to add a polymerization inhibitor or molecular oxygen in order to suppress the polymerization of the vinyl group in the acrylic ester derivative at the time of washing or concentration for taking out the acrylic ester derivative.

Examples of the above polymerization inhibitor include, but are not limited to, hydroquinone, hydroquinone monomethyl ether, p-benzoquinone, t-butylcatechol, phenothiazine and the like. Only one kind of these polymerization inhibitors may be used, or two or more kinds thereof may be appropriately mixed and used. The amount of the polymerization inhibitor added is not particularly limited, but it is preferably used within the range of 0.001% by weight to 5% by weight with respect to the acrylic ester derivative.

As the molecular oxygen, for example, air can be used. In this case, concentration may be performed while blowing air during the removal of the organic solvent or water, that is, while performing so-called bubbling. In order to sufficiently suppress the above polymerization, it is preferable to use a polymerization inhibitor in combination with molecular oxygen.

The pressure at the time of washing and at the time of removing the organic solvent and water is not particularly limited and may be normal pressure (atmospheric pressure), reduced pressure or increased pressure.

As described above, according to the purification method of the present invention, the crude acrylic acid ester derivative containing the non-polymerizable alcohol is washed with the detergent containing at least water to remove the crude acrylic acid ester derivative from the crude acrylic acid ester derivative. The polymerizable alcohol can be extracted into the aqueous layer and removed. As a result, impurities in the acrylic acid ester derivative can be reduced, and an acrylic acid ester derivative that can efficiently perform urethane crosslinking and melamine crosslinking can be obtained.

By the way, in the acrylic acid ester derivative after the above-mentioned purification treatment, as an impurity other than the non-polymerizable alcohol, an ether dimer, an acetal dimer or an α-dimer having two or more double bonds in the molecule is used. There exists a dimer (hereinafter, referred to as an ester-type dimer) or the like which is transesterified between a hydroxyl group of a hydroxyalkyl acrylic acid or an acrylic ester derivative and an ester group, and which is linked by an ester bond. Each of these impurities is composed of a crosslinkable component, and when an acrylic acid ester derivative containing these crosslinkable components as impurities is polymerized, a crosslinking reaction may occur and gelation may occur.

Therefore, by removing these crosslinkable components, a higher-purity acrylic acid ester derivative can be obtained and the crosslinking reaction can be prevented.
The crosslinkable component, rather than the solubility of the acrylic ester derivative, washed with an organic solvent having a higher solubility of the crosslinkable component, or by washing with a detergent containing at least water, easily separated, Can be removed.

As the organic solvent in which the solubility of the crosslinkable component is higher than that of the acrylic ester derivative, compounds having a solubility parameter of 8.5 or less are preferable, and compounds having a solubility parameter in the range of 7 to 8.3 are preferable. More preferable. If the above dissolution parameter is greater than 8.5,
It is not preferable because only the crosslinkable component cannot be selectively dissolved. By washing the acrylic ester derivative containing the crosslinkable component with an organic solvent having a solubility parameter of 8.5 or less, the crosslinkable component can be selectively extracted and removed into the organic solvent layer.

Specific examples of the organic solvent having a solubility parameter of 8.5 or less include, for example, hexane (solubility parameter 7.3: hereinafter, in the exemplified compounds, the values in parentheses () indicate the solubility parameter) and cyclohexane ( 8.2),
Examples thereof include aliphatic hydrocarbons such as methylcyclohexane (7.8), but are not particularly limited.

The amount of the organic solvent having a solubility parameter of 8.5 or less is preferably 0.01 to 100, and more preferably 0.1 to 10 by weight ratio with respect to the acrylic ester derivative containing the crosslinkable component. More preferable. If the amount of the organic solvent used with respect to the acrylic ester derivative is less than 0.01 in weight ratio, the crosslinkable impurities cannot be sufficiently removed, which is not preferable. On the other hand, if the amount of the organic solvent used with respect to the acrylic ester derivative is more than 100 by weight, the productivity is lowered, which is not preferable.

The detergent used for removing the crosslinkable components is a detergent containing at least water,
It is possible to use water or a mixed solution of water and an organic solvent that separates water into two layers. By washing the acrylic acid ester derivative containing the crosslinkable component with a detergent containing at least water, the acrylic acid ester derivative can be extracted into a water layer to remove the crosslinkable component from the acrylic acid ester derivative.

The amount of water used for removing the above-mentioned crosslinkable component, that is, the amount of water contained in the above-mentioned detergent is such that even if only water is used as the detergent, water is used as the detergent. Also, when a mixed solution of water and an organic solvent that separates into two layers is used, the weight ratio with respect to the acrylic ester derivative containing the crosslinkable component is preferably within a range of 0.01 to 100, and a range of 0.1 to 50. Is more preferable.
If the amount of water used with respect to the acrylic acid ester derivative is less than 0.01 by weight, the yield of the finally obtained acrylic acid ester derivative decreases, which is not preferable.
On the other hand, if the amount of water used with respect to the acrylic ester derivative is more than 100 by weight, the productivity is lowered, which is not preferable.

The organic solvent contained in the cleaning agent for removing the crosslinkable component is not particularly limited as long as it is an organic solvent which is insoluble in water, but the solubility parameter is preferably 10 The following solvents, which have a solubility parameter in the range of 7.0 to 9.5, are more preferable.
When the solubility parameter exceeds 10, it takes time to separate the two layers from water and productivity is lowered, which is not preferable.

The organic solvent having a solubility parameter of 10 or less is not particularly limited, but specifically,
For example, benzene (solubility parameter 9.2: in the following compounds, the values in the parentheses () indicate the solubility parameter), aromatic hydrocarbons such as toluene (8.9), xylene (8.8): ethyl acetate (9.1), Acetate esters such as butyl acetate (8.5); propionate esters such as ethyl propionate (8.4); ketones such as methyl ethyl ketone (9.3), methyl propyl ketone (8.7) and methyl isobutyl ketone (8.4). When the above cleaning agent contains the above organic solvent in addition to water, there is an advantage that the liquid separating property is improved and the productivity is improved.

The amount of the organic solvent used for removing the above-mentioned crosslinkable component, that is, when the mixed solution of water and an organic solvent that separates water into two layers is used as the cleaning agent, it is contained in the cleaning agent. The amount of the organic solvent to be used is preferably more than 0 and 100 or less, and more preferably more than 0 and 10 or less in weight ratio with respect to the acrylic ester derivative containing the above-mentioned crosslinkable component. If the amount of the organic solvent used with respect to the acrylic acid ester derivative containing the above-mentioned crosslinkable component exceeds 100 by weight, the productivity is lowered, which is not preferable.

The washing method for washing the acrylic ester derivative containing the crosslinkable component is not particularly limited, and the same washing method as described above can be used. However, in this case, since the crosslinkable component is transferred to the organic solvent layer and the acrylic ester derivative is transferred to the water layer, for example, after stirring or line mixing, the mixture is allowed to stand and separated into two layers to remove impurities. By separating the layer (organic solvent layer) and the acrylate derivative layer (water layer), the crosslinkable component can be removed from the acrylate derivative.

Also in this case, the number of times of cleaning is not particularly limited, and the cleaning may be repeated until the effect is sufficiently exerted. Moreover, the acrylic acid ester derivative finally obtained after removing the crosslinkable component can be directly used for various purposes. However, the acrylic acid ester derivative may contain a small amount of the organic solvent used for cleaning. Therefore, the remaining organic solvent may be removed after washing depending on the application. The method for removing the organic solvent is not particularly limited, and the same methods as those described above can be used. The used organic solvent can be recovered and reused.

Further, water can be removed when an acrylic ester derivative which is not an aqueous solution is desired.
The method for removing water is not particularly limited,
For example, a method of evaporating water or adding an organic solvent that azeotropes with water to lower the boiling point and evaporates can be used.

The order of removing the impurities is not particularly limited, and the non-polymerizable alcohol may be removed first, and then the crosslinkable component may be removed, or after the crosslinkable component is first removed, The non-polymerizable alcohol may be removed. Further, if the organic solvent and water can be used in common in each cleaning step, the organic solvent and water can be continuously removed to the next step without being removed after each step.

The acrylic acid ester derivative purified by the above-mentioned purification method has high quality and can be suitably used for the various uses mentioned above.

[0057]

The present invention will be described in more detail with reference to the following Examples and Comparative Examples, but the present invention is not limited thereto.

First, a production example of the acrylic ester derivative represented by the general formula (1) is shown below.

[Production Example 1] A 1000 ml pressure resistant reaction vessel equipped with a thermometer, a gas blowing tube, and a stirrer,
Ethyl-α-hydroxymethyl acrylate as acrylic acid ester 130 g, toluene as solvent 100
g, boron trifluoride ethyl ether complex as a catalyst
1.4g and hydroquinone as polymerization inhibitor 0.06
5 g was charged and stirred. Next, after blowing nitrogen gas as an inert gas into the above reaction vessel so as to have a pressure of 2.5 kg / cm ² , while maintaining the temperature in the reaction vessel within the range of 35 ° C to 45 ° C, a cyclic 242 g of ethylene oxide as an ether compound was gradually pressed into the reaction solution.

After completion of the press-fitting, the reaction solution was stirred at 50 ° C. for 2 hours to complete the reaction. After the completion of the reaction, the temperature in the vessel was raised to 40 ° C. and the pressure was reduced to 100 mmHg to remove unreacted ethylene oxide. Then, add 3 g of magnesium oxide as an adsorbent to the above reaction solution.
Was added and the mixture was stirred at 50 ° C. for 2 hours to adsorb the boron trifluoride ethyl ether complex in the solution in the magnesium oxide to form an insoluble matter. After that, the reaction solution was suction-filtered to remove the insoluble matter. Then, the obtained filtrate was transferred to a rotary evaporator,
Light yellow transparent liquid by removing toluene at 40mmHg and 70 ℃ 342
g was obtained as the reaction product, ie the crude acrylic acid ester derivative.

The hydroxyl value of the crude acrylic ester derivative measured by a predetermined method was 156.4 mg KOH / g, and from this result, 5.2 mol of ethylene oxide was added to 1 mol of ethyl-α-hydroxymethyl acrylate. I knew that.

[Production Example 2] Ethyl-α-hydroxymethyl acrylate 130 was placed in a 1000 ml reaction vessel equipped with a thermometer, a gas blowing tube, a dropping device and a stirring device.
g, 1.4 g of tungstophosphoric acid as a catalyst, and 0.065 g of hydroquinone were charged and stirred. On the other hand, propylene oxide 2 as a cyclic ether compound was added to the dropping device.
I put 03g. Next, air was blown into the above reaction solution and propylene oxide in the dropping apparatus was gradually added dropwise to the reaction solution while maintaining the temperature in the reaction vessel within the range of 45 ° C to 55 ° C.

After completion of the dropping, the reaction solution was stirred at 50 ° C. for 2 hours to complete the reaction. After the reaction was completed, the temperature inside the container was raised to 70 ° C and the temperature was 100 mmHg.
The pressure was reduced to 2, and unreacted propylene oxide was removed over 2 hours. Further, 3 g of magnesium oxide was added to the reaction solution, and the mixture was stirred at 50 ° C. for 2 hours to adsorb tungstophosphoric acid in the solution to the magnesium oxide to form an insoluble matter. Then, the reaction solution was suction filtered to remove the insoluble matter, and 298 g of a pale yellow transparent liquid was added as a reaction product,
That is, it was obtained as a crude acrylic acid ester derivative.

The hydroxyl value of the crude acrylic acid ester derivative measured by a predetermined method was 181.1 mg KOH / g, and from this result, 3.1 mol of propylene oxide was added per mol of ethyl-α-hydroxymethyl acrylate. I found out that

Example 1 A 500 ml separating funnel was charged with 100 g of the crude acrylic acid ester derivative obtained in Production Example 1 and 10 g of water. Next, the above separating funnel was shaken and mixed 10 times, and then allowed to stand at room temperature. After standing still, the solution in the separating funnel was immediately separated into two layers. Then, after a lapse of 30 minutes, the lower aqueous layer was extracted. Thereafter, the upper layer remaining in the separating funnel, that is, the acrylic ester derivative layer was transferred to a rotary evaporator, and water was removed at 40 mmHg and 50 ° C. to obtain 67 g of a pale yellow transparent liquid. The components of the obtained pale yellow transparent liquid were analyzed using liquid chromatography. The analytical values are shown in Table 1.

Example 2 In a 2000 ml separating funnel, 100 g of the crude acrylic acid ester derivative obtained in Production Example 1 and water were added.
100 g and 1000 g of toluene were added. Next, the above separating funnel was shaken and mixed 10 times, and then allowed to stand at room temperature. After standing still, the solution in the separating funnel was immediately separated into two layers. Then, after a lapse of 30 minutes, the lower aqueous layer was extracted. After that, the upper layer remaining in the separatory funnel, that is, the acrylic ester derivative layer was transferred to a rotary evaporator, and 40 mm
Hg, light yellow transparent liquid by removing water and toluene at 50 ℃
78 g are obtained. Regarding the components of the obtained pale yellow transparent liquid,
It was analyzed using liquid chromatography. The analytical values are shown in Table 1.

Example 3 In a 1000 ml separating funnel, 100 g of the crude acrylic acid ester derivative obtained in Production Example 1 and water were added.
200 g and 200 g of ethyl acetate were added. Next, the above separating funnel was shaken and mixed 10 times, and then allowed to stand at room temperature. After standing still, the solution in the separating funnel was immediately separated into two layers. Then, after a lapse of 30 minutes, the lower aqueous layer was extracted. After that, the upper layer remaining in the separating funnel, that is, the acrylic ester derivative layer was transferred to a rotary evaporator, and
Water and ethyl acetate were removed at mmHg and 50 ° C. to obtain 44 g of a pale yellow transparent liquid. The components of the obtained pale yellow transparent liquid were analyzed using liquid chromatography. The analytical values are shown in Table 1.

Comparative Example 1 The components of the crude acrylic acid ester derivative obtained in Production Example 1 were analyzed by liquid chromatography. The analytical values are shown in Table 1.

Example 4 In a 1000 ml separating funnel, 100 g of the crude acrylic acid ester derivative obtained in Production Example 2 and water were added.
200 g and 500 g of toluene were added. Next, the above separating funnel was shaken and mixed 10 times, and then allowed to stand at room temperature. After standing still, the solution in the separating funnel was immediately separated into two layers. Then, after a lapse of 30 minutes, the lower aqueous layer was extracted. After that, the upper layer remaining in the separatory funnel, that is, the acrylic ester derivative layer was transferred to a rotary evaporator, and 40 mm
80g of light yellow transparent by removing water and toluene at Hg, 50 ℃
87 g of a weight% aqueous solution was obtained. The components of the obtained pale yellow transparent liquid were analyzed using liquid chromatography. The analytical values are shown in Table 1.

Comparative Example 2 The components of the crude acrylic acid ester derivative obtained in Production Example 2 were analyzed using liquid chromatography. The analytical values are shown in Table 1.

[0071]

[Table 1]

As is clear from the results shown in Table 1 above, the crude acrylic acid ester derivative was purified by the purification method according to this example, whereby the glycol or glycol monoester contained in the crude acrylic acid ester derivative was purified. Non-polymerizable alcohols such as ethyl ether can be removed.

[0073]

As described above, the method for purifying an acrylic acid ester derivative according to the first aspect of the present invention comprises the general formula (1) containing a non-polymerizable alcohol as an impurity.

[0074]

Embedded image

(In the formula, R ₁ and R ₂ each independently represent a hydrogen atom or an organic residue, R ₃ represents an organic residue,
n represents a positive number of 1 to 3 and m represents a positive number of 1 to 10), and the acrylic ester derivative represented by the formula is washed with a detergent containing at least water.

As described above, the method for purifying an acrylic acid ester derivative according to the second aspect of the present invention is the same as the method for purifying an acrylic acid ester derivative according to the first aspect. Is in the range of 0.001 to 100 by weight.

The method for purifying an acrylic acid ester derivative according to claim 3 of the present invention is, as described above, the method for purifying an acrylic acid ester derivative according to claim 1 or 2, wherein the cleaning agent is water and two layers. The organic solvent to be separated is further included, and the solubility parameter of the organic solvent is 7 or more.

As described above, the method for purifying an acrylic acid ester derivative according to the present invention is the method for purifying an acrylic acid ester derivative according to claim 3, wherein an organic solvent is used for the acrylic acid ester derivative. The amount is more than 0 and 100 or less by weight.

As described above, according to the present invention, an acrylic acid ester derivative containing a non-polymerizable alcohol as an impurity is washed with a detergent containing at least water to remove the acrylic acid ester derivative from the non-polymerizable alcohol. Can be extracted into the aqueous layer and removed. As a result, it is possible to reduce impurities and obtain an acrylic ester derivative capable of efficiently performing urethane crosslinking and melamine crosslinking.

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Yuichi Kita 992, Nishioki, Okihama-shi, Aboshi-ku, Himeji-shi, Hyogo

Claims (4)

[Claims] 1. A general formula (1) containing a non-polymerizable alcohol as an impurity: (In the formula, R ₁ and R ₂ each independently represent a hydrogen atom or an organic residue, R ₃ represents an organic residue, n represents a positive number of 1 to 3, and m represents a positive number of 1 to 10. The method for purifying an acrylic acid ester derivative is characterized in that the acrylic acid ester derivative represented by the formula (3) is washed with a detergent containing at least water. 2. The method for purifying an acrylic ester derivative according to claim 1, wherein the amount of water used with respect to the acrylic ester derivative is in the range of 0.001 to 100 in weight ratio. 3. The cleaning agent further contains an organic solvent that separates from water into two layers, and the solubility parameter of the organic solvent is 7
The above is the method for purifying an acrylic acid ester derivative according to claim 1 or 2. 4. The method for purifying an acrylic acid ester derivative according to claim 3, wherein the amount of the organic solvent used with respect to the acrylic acid ester derivative is more than 0 and 100 or less by weight.