JPH0717577B2 - Process for producing methacrylic acid ester of ether group-containing alcohol - Google Patents

Description

The present invention relates to a method for producing a methacrylic acid ester of an ether group-containing alcohol.

(Prior Art) Methacrylic acid ester of ether group-containing alcohol is
It is known to be a compound that is easily oxidized due to the presence of an ether group, is easily polymerized during the synthesis and purification of the ester, and is difficult to manufacture. Even if it can be synthesized without polymerization, it is extremely difficult to avoid problems such as marked coloring and poor storage stability.

For example, in Japanese Patent Publication No. 52-49449 and Japanese Patent Laid-Open No. 50-50313, the reaction liquid obtained by the esterification reaction is neutralized with an aqueous alkaline solution, and then the oil layer is separated and distilled to cause coloring. A method for obtaining an ether group-containing methacrylic acid ester having a small amount and good storage stability is described.

In JP-A-62-106057, methacrylic acid, a polyether polyol and an acidic catalyst are heated, and a phenolic polymerization inhibitor is added at a temperature of 70 ° C. The method of obtaining is described.

(Problems to be solved by the invention) However, these Japanese Patent Publication No. 52-49449 and Japanese Patent Laid-Open No. 50-5
In both 0313 and JP-A-62-106057, there is no description of polymerization prevention during the synthesis, especially, the above-mentioned method at the time of synthesis of other general methacrylic acid esters. Therefore, it is inevitable that polymerization often occurs.

Further, Japanese Patent Publication No. 52-49449 and Japanese Patent Laid-Open No. 50-50313 disclose that the methacrylic acid ester, which can be purified by distillation, can be improved in coloring and storage stability, but the methacrylic acid ester is Therefore, the number of methacrylic acid esters that are easily polymerized with methacrylic acid and that can be purified by distillation is very limited, and thus the coloration and storage stability of many ether group-containing methacrylic acid esters cannot be improved.

Further, JP-A-62-106057 discloses a method of post-adding a polymerization inhibitor as a method for dimming methacrylic acid esters that cannot be purified by distillation. However, this method does not sufficiently prevent polymerization. Moreover, it is not possible to obtain a sufficient effect for lightening.

The present invention provides a method for producing a methacrylic acid ester of an ether group-containing alcohol which prevents polymerization during synthesis and purification, has little coloration and is excellent in storage stability.

(Means for Solving Problems) That is, the present invention is characterized in that an ether group-containing alcohol is treated with an alkaline substance and then transesterified with methyl methacrylate in the presence of the alkaline substance. To a method for producing a methacrylic acid ester.

In the present invention, the ether group-containing alcohol is an alcohol having a polyalkylene glycol type ether bond in the molecule, and the alkylene oxide is added to a ring-opening polymer of alkylene oxide such as ethylene oxide or propylene oxide, alcohol, or phenol. Form of compound and the like.

As the ether group-containing alcohol, the following general formula (I),
It is preferable to use the compound represented by (II) or (III).

HOR ¹ OkH (I) (in the formula, R ¹ represents an alkylene group, k represents an integer), R ² —OR ¹ OlH (II) (in the formula, R ¹ represents an alkylene group, R ² represents a carbon atom) Represents a hydrogen group, l represents an integer) or HOR ¹ mO-R ³ -OR ¹ OnH (III) (wherein R ¹ represents an alkylene group, R ³ represents a divalent group, m
And n represents an integer).

The compound represented by the general formula (I) is preferably a compound in which R ¹ is an alkylene group having 2 to 5 carbon atoms and k is an integer of 2 to 30.

Examples of the compound represented by the general formula (I) include diethylene glycol, triethylene glycol, tetraethylene glycol, polyethylene glycol, dipropylene glycol, tripropylene glycol, tetrapropylene glycol and polypropylene glycol.

As the compound represented by the general formula (II), R ¹ is an alkylene group having 2 to 5 carbon atoms, R ² is a saturated or unsaturated aliphatic hydrocarbon group having 20 or less carbon atoms, and 20 or less carbon atoms Compounds which are saturated or unsaturated alicyclic hydrocarbon groups or aromatic hydrocarbon groups having 20 or less carbon atoms and in which l is an integer of 1 to 30 are preferable.

The compound represented by the general formula (II) is methanol,
Ethanol, propanol, allyl alcohol, butanol, pentanol, cyclopentanol, hexanol, cyclohexanol, norborneol, norbornenyl alcohol, norbornyl methyl alcohol, norbornenyl methyl alcohol, adamantanol, tricyclo [5.2.1.0 ^{2 , 6} ] Deca-3-en-8-ol,
Tricyclo [5.2.1.0 ^2,6 ] deca-3-en-9-ol, tricyclo [5.2.1.0 ^2,6 ] decan-8-ol, tricyclo [5.2.1.0 ^2,6 ] decan-3-ylmethanol,
Tricyclo [5.2.1.0 ^2,6 ] decan-4-yl methanol, borneol, isoborneol and other monohydric alcohols, phenols, alkylphenols and other monohydric phenols, and other compounds in which ethylene oxide, propylene oxide, etc. are addition-polymerized, Tricyclo [5.2.1.0 ^2,6 ] deca-3,8-diene (conventional name: dicyclopentadiene) added with ethylene glycol, propylene glycol, etc., and addition polymerization of ethylene oxide, propylene oxide, etc. Is mentioned.

As the compound represented by the general formula (III), R ¹ is an alkylene group having 2 to 5 carbon atoms, and R ³ is a saturated or unsaturated divalent hydrocarbon group having 20 or less carbon atoms, and 20 carbon atoms. containing divalent alicyclic hydrocarbon group, or of 20 or less aromatic hydrocarbon group having a carbon of the following saturated or unsaturated, -O- or -SO ₂ - may have a structural unit of 2 Is the basis of valence,
A compound in which m and n are integers of 2 to 30 in which the sum of m and n is preferable.

Examples of the compound represented by the general formula (III) include 1,4-butanediol, 1,3-butanediol, 1,6-hexanediol, cyclohexanedimethylol, 3,8-bis (hydroxymethyl) tricyclo [5.2 .1.0 ^2,6 ] decane, 3,9-bis (hydroxymethyl) tricyclo [5.2.1.0 ^2,6 ] decane, 4,8-bis (hydroxymethyl) tricyclo [5.2.1.
0 ^2,6] polyalcohols decane, and the like bisphenol A, bisphenol S, bis (p- hydroxyphenyl) ethylene oxide and polyhydric phenols such as ether, compounds propylene oxide or the like by addition polymerization .

Further, among ether group-containing alcohols, alcohols having a double bond or an alicyclic structure in the molecule are compounds that are particularly easily oxidized.

When such an ether group-containing alcohol is used, it is often already oxidized, and when left in the air, it is further oxidized, and when it inhales air, the amount thereof is remarkably increased. it is conceivable that. When such an ether group-containing alcohol is esterified with methyl methacrylate while itself being oxidized, it causes polymerization of the double bond of the methacryloyl group during synthesis and purification, the product is colored, Storage stability will be adversely affected.

By treating such an oxidized ether group-containing alcohol with an alkaline substance, the oxide can be decomposed and an undesirable polymerization reaction or coloration can be suppressed.

As the alkaline substance, sodium, potassium, lithium, magnesium, calcium, sodium hydride, potassium hydride, lithium hydride, butyl lithium, phenyl lithium, sodium hydroxide, potassium hydroxide, lithium hydroxide, sodium, potassium or lithium. Methoxide, ethoxide, propoxide or butoxide of
Examples thereof include alkoxides of the ether group-containing alcohol.

Alcalic substances are sodium, potassium, lithium,
At least one compound of these hydroxides and these alkoxides is preferable. Hydroxides and alkoxides of sodium, potassium and lithium are more preferable from the viewpoint of handling such as low corrosiveness and generation of hydrogen during the reaction. Particularly preferred are lithium hydroxide, lithium methoxide, lithium ethoxide, lithium propoxide and lithium butoxide.

These may be used after being dissolved or dispersed in a solvent such as alcohol such as methanol or ethanol.

The amount of the alkaline substance used is preferably 0.01 to 5.0% by weight, more preferably 0.05 to 2.0% by weight, based on the ether group-containing alcohol. If the amount of the alkaline substance is small, the effect of decomposing the oxide cannot be sufficiently obtained, and if the amount is too large, there is no particular improvement in this effect.

These alkaline substances may be treated and reacted by first adding the total amount to the ether group-containing alcohol, but it is also possible to divide the required amount of alkaline substances during treatment or transesterification and add additional substances. good.

The treatment of the ether group-containing alcohol with the alkaline substance is preferably carried out in a reaction vessel equipped with an ordinary stirring device. Alternatively, an alkaline substance can be added to the storage container of the ether group-containing alcohol, but many alkaline substances are solid and moreover not easily dissolved in the ether group-containing alcohol. For example, it is more efficient that the liquid is in a fluid state to some extent.

The treatment conditions differ depending on the type and amount of the alkaline substance used, but it is preferable to perform the treatment at a temperature of 0 to 120 ° C. The treatment time may be appropriately determined, but a range of 5 hours or less is sufficient. For example, when a metal alkali is used, the temperature is preferably low, and the treatment can be completed at a low temperature in a substantially short time. On the other hand, when an alkaline substance such as an alkali hydroxide that is difficult to dissolve in an ether group-containing alcohol is used, solid-liquid contact is used, and therefore it may be preferable to heat or treat for a long time. However, in any case, the object can be achieved by gently stirring at room temperature (without special heating or cooling) for 1 minute to 1 hour. In addition, in an actual manufacturing facility, after adding an alkaline substance to the ether group-containing alcohol,
When methyl methacrylate is added, it takes some time to charge methyl methacrylate. Therefore, even if methyl methacrylate is charged immediately after the addition of the alkaline substance to the ether group-containing alcohol and the transesterification reaction described below is performed, The process can also be substantially completed. If the ether group-containing alcohol is treated with an alkaline substance and the substance is not separated, the treatment liquid thus obtained can suppress the formation of oxides even after being stored for several days. Therefore, after the treatment, the treated liquid can be stored and then subjected to transesterification reaction with methyl methacrylate.

Since the alkaline substance functions as a catalyst for the transesterification reaction, it is possible to add methyl methacrylate to the treatment liquid to cause the transesterification reaction without separation from the treatment liquid after the treatment. If it is necessary to remove alkaline substances from the processing solution, neutralize with acid, wash with water,
The alkaline substance can be removed due to excess or the like.

In the transesterification reaction between the ether group-containing alcohol and methyl methacrylate, the alkaline substance is preferably present in an amount of 0.01 to 10.0% by weight, more preferably 0.05 to 5.0% by weight, based on the ether group-containing alcohol. If the amount is too small, the transesterification reaction becomes slow, and if the amount is too large, there is no particular advantage, and a complicated operation is required to remove the alkaline substance after the reaction is completed.

When the alkaline substance is not separated from the treatment liquid, it is not necessary to newly add the alkaline substance during the transesterification reaction, and the alkaline substance is appropriately added so that the alkaline substance is present in the transesterification reaction. You may add.

The above-mentioned alkaline substance can be used as the alkaline substance to be present in the transesterification reaction, and this alkaline substance has a function of suppressing the formation of an oxide during the transesterification reaction.

In the transesterification reaction, methyl methacrylate is preferably used in the range of 2 to 10 mol per 1 equivalent of the hydroxyl group of the ether group-containing alcohol. If the amount of methyl methacrylate is too small, the reaction becomes slow and unreacted ether group-containing alcohol tends to remain. On the other hand, if the amount of methyl methacrylate is too large, the productivity will be poor, and it will take a long time to recover the excess methyl methacrylate after the reaction.

In the present invention, it is preferable that a polymerization inhibitor is present during the transesterification reaction. As the polymerization inhibitor, use known polymerization inhibitors such as hydroquinone, hydroquinone monomethyl ether, t-butylcatechol, parabenzoquinone, 2,5-diphenylparabenzoquinone, phenothiazine, diphenylamine, phenyl-β-naphthylamine and methylene blue. You can The amount of these polymerization inhibitors used is 15 with respect to the ether group-containing alcohol.
It is preferably up to 10,000 ppm, particularly preferably 50 to 1,000 ppm. If it is too small, the effect of preventing polymerization by using a polymerization inhibitor may not always be sufficient.
If the amount is too large, it may have an adverse effect such as inhibiting the polymerization when the product in which the polymerization inhibitor is not removed is polymerized. Hydroquinone monomethyl ether and phenothiazine are particularly preferable in that the obtained reaction liquid is less colored. In the present invention, it is preferable to blow a small amount of molecular oxygen during the reaction to prevent polymerization of the reaction solution. The molecular enzyme is preferably used in a diluted form such as air. The blowing of the molecular enzyme is also preferable for preventing the polymerization of methyl methacrylate existing as a gas or a liquid in the rectification column when the rectification column is used as described later. The amount of molecular oxygen used depends on the reactor shape and stirring power, but it is 5 to 500 ml / min (25 to 2,500 ml / air as air) for 1 mol of the alcohol containing ether group. min)
Blow at the speed of.

The transesterification reaction is preferably carried out at 60 to 130 ° C under normal pressure or reduced pressure.

Further, as a reaction mode of the transesterification reaction, a method generally known by those skilled in the art for producing a methacrylic acid ester by transesterification of methyl methacrylate and alcohol can be adopted. In this method, in order to increase the conversion rate of the raw material alcohol, it is preferable to carry out the synthesis while distilling methanol out of the system by azeotropic distillation of by-produced methanol and methyl methanocrylate.

Therefore, as the reaction apparatus, it is preferable to use a batch reaction tank equipped with a rectification column. In this case, the transesterification reaction is performed as follows, for example. That is, when the reaction is carried out at normal pressure, the methanol and methyl methacrylate that are produced will boil when the temperature of the reaction solution rises to about 100 ° C. In the rectification column, the reflux ratio is controlled (range of about 1 to 20) so that the overhead temperature is in the range of 64 ° C to 70 ° C, which is the azeotropic point of methanol and methylmethacrylate, and the methylmethacrylate system The transesterification reaction is completed while removing methanol outside the system as an azeotrope with methyl methacrylate while minimizing the amount of distillation outside. In this case, the temperature of the reaction solution is 110 near the end of the reaction.
The temperature rises to ~ 125 ° C and the top temperature approaches 100 ° C. That is, it is preferable to increase the reflux ratio (10 or more) to reduce the deviation from the azeotropic composition of methanol and methyl methacrylate to reduce the loss of methyl methacrylate.

On the other hand, when methanol stays in the reaction system at a high concentration for a long time, a by-product in which methanol is added to the unsaturated bond of methacrylic acid ester is generated. It is also necessary to promptly distill out of the system.

Here, a large amount of methyl methacrylate liquid and gas vaporized from the reaction tank exist in the rectification column. However, even if the polymerization inhibitor is charged in the reaction tank, it does not easily vaporize, and thus there is almost no polymerization inhibitor in the rectification column, and methyl methacrylate may polymerize. Therefore, as described above, a method of introducing molecular oxygen (for example, air) into the reaction vessel so that molecular oxygen coexists in the rectification column, or a polymerization inhibitor in the reflux liquid returned from the column of the rectification column to the column Is preferably added.

The reaction solution obtained by the transesterification reaction is often composed of a solution containing methyl methacrylate, a methacrylic acid ester of the product, a small amount of the starting alcohol and a polymerization inhibitor, and an insoluble material such as an alkaline substance. .

To obtain the product by substantially isolating the product methacrylic acid ester from this reaction solution, a method widely used in the art can be used. That is, methyl methacrylate may be distilled off as it is from the reaction solution, and subsequently the methacrylic acid ester of the desired product may be obtained by distillation (usually by vacuum distillation). Alternatively, the reaction solution may be washed with water or washed with water to remove alkaline substances (catalysts) and the like, and then methyl methacrylate may be distilled off to obtain a product. In some cases, the product may be further purified by distillation. Good. Also,
The product may be obtained by removing the methyl methacrylate from the reaction solution and then removing the alkaline substance (catalyst) or the like by washing with water or washing with water, and in this case also, the product may be further purified by distillation. In addition, it is convenient to use an alkaline substance such as lithium hydroxide or lithium methoxide because it is easy to remove due to excess.

Moreover, the preferable aspect in this invention is shown below.

That is, the reactor equipped with rectification (actual number of stages 2 to 15; more stages may be used, but 2 to 15 is sufficient) is replaced with nitrogen, and ether group-containing alcohol is first charged. Next, an alkaline substance is added and stirring is performed. Then, a polymerization inhibitor is added and methyl methacrylate is charged. The temperature is raised with stirring under normal pressure or reduced pressure, and when the temperature of the reaction solution reaches 50 ° C, air or oxygen is blown in. The air or oxygen blown at this time is preferably dry, and the water content is 1% by weight or less, more preferably 1,000 ppm.
It is the following. The compressed air can be adsorbed and removed with sulfuric acid, molecular sieve, calcium chloride, silica gel or the like, or can be cooled to condense and remove the contained water. Further, liquefied and purified oxygen can be used as it is or diluted with nitrogen or the like.

Since the alkaline substance may deactivate the function as a catalyst during the reaction due to the influence of moisture in water or air,
It is also effective to continuously add a small amount of the alkaline substance during the reaction, or to divide the required amount of the alkaline substance every 10 to 30 minutes and additionally add the alkaline substance.

When the liquid temperature rises (approx. 100 ° C at atmospheric pressure) and the vapor begins to rise, the rectification column is first brought to full reflux and the top temperature is the azeotropic temperature of methanol and methyl methacrylate (at atmospheric pressure). In the case of the temperature of 64 to 66 ° C), then set the reflux ratio to 1 to 10
The methanol produced as a by-product is extracted together with azeotropic methyl methacrylate. The reflux ratio during the reaction is as described above.

As a method of adding the polymerization inhibitor to the reflux liquid returned to the rectification column during the reaction, the same polymerization inhibitor as the one charged in the reaction liquid was dissolved in methyl methacrylate in advance, and this was added. A method of continuously adding to the reflux liquid using a pump or the like is preferable.

In addition, when passing the reaction solution after the reaction,
A method of mixing about 2.0% by weight of a super-auxiliary agent (usually diatomaceous earth or the like) in the reaction solution or pre-coating on the over-surface is advantageous.

(Function) Ether group-containing alcohols are easily oxidizable, and when they are used, they are often already oxidized, and when left in the air, they are further oxidized, and when molecular oxygen is blown, they are oxidized. It is considered that the amount to be treated increases significantly.

Oxides can be decomposed by treating this alcohol with an alkaline substance, and even if air is blown in under the temperature conditions of the transesterification reaction in the presence of the alkaline substance and the polymerization inhibitor, it is not oxidized. No oxide is formed in the system.

By treating with an alkaline substance, polymerization during synthesis and purification can be prevented, and it becomes possible to produce an ether group-containing methacrylic acid ester with little coloration and excellent storage stability.

(Example) An example of the present invention will be described.

In addition, in the following examples, the presence or absence of a polymer was determined by the following method.

Judgment of presence or absence of formation of polymer A methanol solubility test was conducted. That is, 5 g of a sample and 15 g of methanol were placed in a test tube, and the presence or absence of insoluble matter (whether or not cloudy) was observed with the naked eye when thoroughly mixed by shaking to determine the presence or absence of a polymer.

Example 1 A 14-necked flask equipped with a stirrer, a thermometer, an air introduction tube and a rectification column (10 stages; Sneader type) was placed in a polyethylene glycol monodicyclopentenyl ether. (Obtained by adding ethylene glycol to tricyclo [5.2.1.0 ^2,6 ] deca-3,8-diene in the presence of an acid catalyst and then addition-polymerizing ethylene oxide to this product.) 206 g (0.5 mol) were charged. Then, 1.0 g of granular lithium hydroxide (0.5% by weight of alcohol) was added thereto, and the mixture was gently stirred at 40 ° C for 30 minutes. Potassium hydroxide was dispersed in the solution. Next, 200 g of methyl methacrylate
(20 mol) and hydroquinone monomethyl ether 0.12 g
Was charged and the temperature was raised while introducing air (water content 150 ppm) into the reaction solution at a rate of 50 ml / min. Initially the reaction liquid temperature is about 10
When the temperature rose to 0 ° C, the azeotropic mixture of methanol and methyl methacrylate began to distill from the top of the rectification column.
The reflux ratio was about 2, and the reaction was carried out while distilling off methanol as an azeotrope with methyl methacrylate so that the temperature at the top of the column was in the range of 64-66 ° C.

Incidentally, 0.5 g of granular lithium hydroxide was added 30 minutes and 1 hour after the start of distillation of the azeotropic mixture of methanol and methyl methacrylate (hereinafter, simply referred to as “reaction start”) (in the pretreatment, 1.0% by weight of alcohol, including those added).

The reaction was carried out for 3 hours from the start of the reaction. Since the temperature at the top of the column began to rise and rose to about 90 ° C., the reflux ratio was gradually increased accordingly, and finally it was adjusted to 10, and the reaction was continued for 1 hour. At this point, that is, after 4 hours from the start of the reaction, the reaction solution was analyzed by gas chromatography, and the total amount of polyethylene glycol monodicyclopentenyl ether was 0.5% (area%) with respect to the total amount of the methacrylic acid ester of the product alcohol. The reaction was terminated. No polymer was formed during the reaction and in the reaction solution after the reaction was completed.

Then, the reaction solution temperature was set to 100 ° C, methyl methacrylate was distilled off while gradually lowering the pressure, and finally set to 40 mmHg, and when the methyl methacrylate content rate reached 0.3% by gas chromatography analysis. The removal of excess methyl methacrylate was stopped. After this, at 70 ℃, overpressure 1kg / cm
^In Step ² , using Toyo Paper 5B (over 70 cm ² ) paper (over 13 minutes), 230 g of a pale yellow transparent liquid (hue: Hazen colorimeter 150) was obtained. Gas chromatographic analysis of this liquid showed that the total methacrylic acid ester of polyethylene glycol monodicyclopentenyl ether had a purity of 98.3% (area). No polymer was detected.

Comparative Example 1 206 g of polyethylene glycol monodicyclopentenyl ether (same as in Example 1) was placed in the same apparatus as in Example 1.
(0.5 mol), titanium tetraisopropoxide, 4.0 g, hydroquinone monomethyl ether 0.12 g and methyl methacrylate 200 g (2.0 mol) were charged, and the reaction was carried out while introducing air at a rate of 50 ml / min.

Immediately after the start of the reaction, formation of a polymer was observed (a small amount of the reaction solution was sampled, titanium tetraisopropoxide was removed, and then a methanol solubility test was conducted.) When heating was continued as it was, about 1 hour later A remarkable formation of a polymer was observed, and the reaction solution became thick and stirring became impossible.

Comparative Example 2 Polyethylene glycol monodicyclopentenyl ether (same as in Example 1) was added with potassium hydroxide in the same manner as in Example 1 and stirred, and then the excess lithium hydroxide was removed. Dried. After treatment with this alkaline substance, 206 g of polyethylene glycol monodicyclopentenyl ether excluding the alkaline substance, 4.0 g of titanium tetraisopropoxide, 0.12 g of hydroquinone monomethyl ether and 200 g (2.0 mol) of methyl methacrylate were charged, and air was supplied. The reaction was carried out in the same manner as in Example 1 while introducing at a rate of 50 ml / min. Formation of a polymer was observed 1 hour after the start of the reaction, and when heating was continued as it was, viscosity increased after about 1 hour and stirring became impossible.

Comparative Example 3 Polyethylene glycol monodicyclopentenyl ether (the same as in Example 1) was placed in a 14-necked flask equipped with a stirrer, a thermometer, an air inlet tube, and a reflux condenser with a water separator.
Charge 206 g (0.5 mol), methacrylic acid 52 g (0.6 mol), toluene 200 g, paratoluene sulfonic acid 20 g, hydroquinone monomethyl ether 0.12 g, and raise the temperature while introducing air at a rate of 50 ml / min to generate water. The mixture was heated to reflux while removing (100 to 120 ° C). Formation of a polymer was observed immediately after the start of the reaction, and when heating was continued as it was, the viscosity increased after about 2 hours and stirring became impossible.

Comparative Example 4 206 g of polyethylene glycol monodicyclopentenyl ether (same as in Example 1) was used in the same apparatus as in Example 1.
5 mol), hydroquinone monomethyl ether 0.12 g and methyl methacrylate 200 g (2.0 mol) were charged, and the air was 50 m.
The temperature was raised while introducing at a rate of 1 / min. Liquid temperature is 10 after 15 minutes
The temperature rose to 0 ° C and the methyl methacrylate started to reflux. After maintaining at this temperature for 30 minutes, 1.0 g of lithium hydroxide was added and the reaction was carried out, but at this point a polymer had already formed in the reaction solution. However, since the viscosity did not increase any further, the reaction was continued and during this period, 0.5 g of lithium hydroxide was added at 30 minutes and 1 hour after the start of the reaction. After reacting for 4 hours, methyl methacrylate was distilled off and passed in the same manner as in Example 1. Since the obtained liquid contains a polymer and is colored brown (Hazen color meter 600), it cannot be used as a product as it is.

Comparative Example 5 In the same apparatus as in Example 1, 206 g of polyethylene glycol monodicyclopentenyl ether (same as in Example 1) was used.
(0.5 mol) was charged, 0.01 g of lithium hydroxide (0.005% of alcohol) was charged therein, and the mixture was stirred at 40 ° C. for 1 hour, then 200 g (2.0 mol) of methacrylic acid and 0.12 g of hydroquinone monomethyl ether were charged into the air (water content). Amount 150ppm)
The temperature was raised while blowing 50 ml / min. No further addition of lithium hydroxide was carried out during the reaction, and the reaction stopped at a reaction rate of 40% one hour after the start of the reaction, and when heating was continued for another hour, a polymer was formed.

Example 2 206 g of polyethylene glycol monodicyclopentenyl ether (same as in Example 1) was added to a device similar to that of Example 1.
(5 mol), charged with 16 g of lithium hydroxide (7.8% by weight of alcohol), stirred for 1 hour at 40 ° C., charged with 200 g (2.0 mol) of methyl methacrylate and 0.12 g of hydroquinone monomethyl ether, and air (water content). Amount 150pp
m) was blown at 50 ml / min and the temperature was raised. After 30 minutes and 1 hour from the start of the reaction, 10 g of lithium hydroxide was added (17.5% by weight of alcohol in total including those added in the pretreatment). Methyl methacrylate was distilled off in the same manner as in Example 1, and the excess time was 54
The yield of the obtained methacrylic acid ester (hue: Hazen colorimeter 150) was 180 g.

Example 3 206 g of polyethylene glycol monodicyclopentenyl ether (same as in Example 1) was added to the same apparatus as in Example 1.
(5 mol) was charged and 28% sodium methoxide-
1.0 g of a methanol solution (0.14% by weight of alcohol as sodium methoxide) was added, and the mixture was stirred at 25 ° C for 30 minutes.

To this, 200 g (2.0 mol) of methyl methacrylate and 0.12 g of hydroquinone monomethyl ether were charged, and the temperature was raised in the same manner as in Example 1 while introducing air (water content 150 ppm) into the reaction solution at a rate of 50 ml / min. To react. From 15 minutes to 3 hours after starting the reaction, 0.5 g of 28% sodium methoxide-methanol solution was added every 15 minutes (total 12 times 6.0.
g, total 7.0 g including those added in the pretreatment as 0.95% by weight of alcohol as sodium methoxide).

After completion of the reaction, methyl methacrylate was distilled off in the same manner as in Example 1 to try again. However, the paper clogged and it was difficult to pass the whole amount. The powder was removed and then dried with Glauber's salt. As a result, hue: Hazen colorimeter 160, total purity of methacrylate of polyethylene glycol monodicyclopentenyl ether 98.1% (area%)
195 g were obtained. No polymer was detected.

Example 4 The methacrylic acid of polyethylene glycol monodicyclopentenyl ether was subjected to the same pretreatment and reaction as in Example 1 except that the air blown during the reaction was undried air having a water content of 2.8% by weight. The ester was synthesized. Gas chromatographic analysis of the reaction solution 4 hours after the start of the reaction revealed that the total amount of polyethylene glycol monodicyclopentenyl ether was 2.4% (area%) with respect to the total amount of methacrylic acid ester of the alcohol as a product. However, after completion of the reaction, methyl methacrylate was distilled off in the same manner as in Example 1. It took 37 minutes to pass, and it was light yellow and transparent (hue: Hazen colorimeter
In 140), 210 g of a liquid containing no polymer was obtained. Gas chromatographic analysis of this liquid revealed that the total methacrylic acid ester of polyethylene glycol monodicyclopentenyl ether had a purity of 96.2% (area%).

Example 5 Polypropylene glycol monodicyclopentenyl ether was placed in the same apparatus as in Example 1. (Produced by addition polymerization of propylene oxide to tricyclo [5.2.1.0 ^2,6 ] deca-3-en-8 (or 9) -ol.) 291 g (0.4 mol) was charged, and 10% lithium methoxy was added to this. 2.0 g of de-methanol solution was added, and the mixture was stirred at 30 ° C for 30 minutes. To this, 160 g (1.6 mol) of methyl methacrylate and 0.16 g of hydroquinone monomethyl ether were charged, and the reaction was carried out in the same manner as in Example 1. After 30 minutes, 1 hour, and 2 hours from the start of the reaction, 10% lithium methoxide-
1.0 g of each methanol solution was added. After the reaction was completed, no polymer was detected in the reaction solution. The reaction solution was sucked through a glass Buchner funnel using Toyo Paper, 5B paper, and then methyl methacrylate was distilled off under the same conditions as in Example 1 to give a pale yellow transparent liquid 305 g.
Was obtained (hue: Hazen colorimeter 200). This liquid contained 98% methacrylic acid ester of polypropylene glycol monodicyclopentenyl ether (saponification value: 69 mgKOH / g), and contained no polymer.

Example 6 146 g (1.0 mol) of allyl alcohol ethylene oxide adduct in the same apparatus as in Example 1. (Obtained by addition-polymerizing ethylene oxide to allyl alcohol) was added, 1.0 g of 28% sodium methoxide-methanol solution was added, and the mixture was stirred at 25 ° C for 20 minutes.
To this was charged 350 g (3.5 mol) of methyl methacrylate and 0.11 g of hydroquinone monomethyl ether, and the reaction was carried out in the same manner as in Example 1. In addition, a 28% sodium methoxide-methanol solution was added to the solution every 30 minutes from the start of the reaction.
Added 5g each. After completion of the reaction (after 4 hours), no polymer was formed in the reaction solution.

The reaction solution was washed with water, sodium methoxide was removed, and methyl methacrylate was distilled off to obtain 210 g (yield: 98%) of a pale yellow transparent liquid (hue: Haase colorimeter 80). The purity of methacrylic acid ester of allyl alcohol ethylene oxide adduct was 98.7% by gas chromatography analysis.
No polymer was included.

10 g of the methacrylic acid ester of this allyl alcohol ethylene oxide adduct was placed in a 18 mmφ test tube and heated at 110 ° C. for 2 hours, but no change such as formation of a polymer was observed.

Comparative Example 6 Allyl alcohol ethylene oxide adduct (same as in Example 3) 146 g (1.0 mol), methacrylic acid 103 g (1.2 mol) and paratoluene sulfonic acid 20 g were placed in the same apparatus as in Comparative Example 3.
Charge 2.16 g of hydroquinone and 200 g of n-hexane, and add 5
The temperature was raised while introducing at a rate of 0 ml / min, and the mixture was heated to reflux while removing the produced water (reaction temperature 70 to 75 ° C). After starting the reaction,
From about 1 hour, the adhesion and coloring of the polymer on the flask wall became remarkable, but the reaction was continued as it was, and after 10 hours, almost no reaction water was produced, so heating was stopped. At this time, a considerable amount of polymer adhered to the flask wall,
Since no polymer was found in the hexane solution, only the hexane-dissolved portion was taken out and washed with a 5% aqueous sodium hydroxide solution to remove paratoluenesulfonic acid and excess methacrylic acid, hydroquinone, etc., and then washed with water. 0.1 g of hydroquinone monomethyl ether was added and hexane was distilled off. The liquid obtained did not contain any polymer, but it was colored brown (color number: Hazen colorimeter 1000 or more), and the purity by gas chromatography analysis was 97.2%.
(Area%). The yield is 80g, and the yield is 37%.
It was. 10 g of this allyl alcohol ethylene oxide adduct methacrylic acid ester was placed in an 18 mmφ test tube and
When it was heated to ℃, 30 minutes later it was solidified by polymerization.

Example 7 A bisphenol A ethylene oxide adduct was placed in the same apparatus as in Example 1. (Obtained by addition-polymerizing ethylene oxide to bisphenol A.) 200.4 g (0.3 mol) and 0.3 g of lithium hydroxide were added, and the temperature was 40 ° C.
The mixture was gently stirred for 1 hour. To this, 240 g (2.4 mol) of methyl methacrylate and 0.06 g of hydroquinone monomethyl ether were added, and the reaction was carried out in the same manner as in Example 1 while introducing air at a rate of 50 ml / min (reaction temperature 100 to 115).
C). The reaction was traced by high performance liquid chromatography analysis.

As in Example 2, the excess methyl methacrylate was distilled off, and a pale yellow transparent liquid (hue: Hazen colorimeter 100) was added to the residue.
28 g was obtained. The purity of the bisphenol A ethylene oxide adduct dimethacrylic acid ester was 95.5%, and the rest was a monoester or the like. No polymer was detected. This was placed in a 10 g 18 mmφ test tube and heated at 110 ° C. for 2 hours, but there was no change.

Comparative Example 7 In the same apparatus as in Example 1, 200.4 g of bisphenol A ethylene oxide adduct, 4.0 g of titanium tetraisopropoxide,
240 g of methyl methacrylate and 0.06 g of hydroquinone monomethyl ether were charged, and the reaction was carried out in the same manner as in Example 1 while charging air at a rate of 50 ml / min. Formation of a polymer was observed 2 hours after the start of the reaction, and when heating was continued, the viscosity increased after about 2 hours and stirring became impossible.

Example 8 A device similar to that used in Example 1 was added with tetraethylene glycol (H
116.4 g (0.6 mol) of OCH ₂ CH _{2 4} OH molecular weight 194) was charged, and 1.0 g of granular sodium hydroxide was added to this, and the mixture was mixed at 80 ° C. for 2 hours.
The mixture was gently stirred for 0 minutes. Cool it to 40 ° C,
400 g (4.0 mol) of methyl methacrylate and 0.10 g of hydroquinone monomethyl ether were charged, and the reaction was carried out in the same manner as in Example 1 while blowing air at a rate of 50 ml / min. Every 30 minutes after the start of the reaction, 0.5 g of 28% sodium methoxide-methanol solution was added. After the completion of the reaction, the same treatment as in Example 3 was carried out to obtain 185 g of a pale yellow transparent liquid (hue: Hazen colorimeter 120) (purity of diester: 96.5%, no polymer). 10 g of this tetraethylene glycol dimethacrylic acid ester was placed in an 18 mmφ test tube and heated at 110 ° C. for 2 hours, but there was no change.

(Effects of the Invention) According to the present invention, it is possible to produce a methacrylic acid ester of an ether group-containing alcohol that prevents polymerization during synthesis and purification, is less colored, and has excellent storage stability.

Claims (6)

[Claims] 1. A process for producing a methacrylic acid ester of an ether group-containing alcohol, which comprises treating an ether group-containing alcohol with an alkaline substance and then performing a transesterification reaction with methyl methacrylate in the presence of the alkaline substance. 2. The process for producing a methacrylic acid ester of an ether group-containing alcohol according to claim 1, wherein an alkaline substance is added to the ether group-containing alcohol and the mixture is stirred, and then methyl methacrylate is further added to carry out a transesterification reaction. 3. The methacrylic acid of the ether group-containing alcohol according to claim 1 or 2, wherein the ether group-containing alcohol is a compound represented by the following general formula (I), (II) or (III). Method for producing ester. HOR ¹ OkH (I) (in the formula, R ¹ represents an alkylene group, k represents an integer), R ² —OR ¹ OlH (II) (in the formula, R ¹ represents an alkylene group, R ² represents a carbon atom) Represents a hydrogen group, l represents an integer) or HOR ¹ mO-R ³ -OR ¹ OnH (III) (wherein R ¹ represents an alkylene group, R ³ represents a divalent group, m
And n represents an integer) 4. A methacrylic acid ester of an ether group-containing alcohol according to claim 1 or 2, wherein the alkaline substance is at least one compound of sodium, potassium, lithium, hydroxides thereof and alkoxides thereof. Manufacturing method. 5. The method for producing a methacrylic acid ester of an ether group-containing alcohol according to claim 1, 2, 3 or 4, wherein the transesterification reaction is carried out in the presence of a polymerization inhibitor. 6. The methacrylic ester of an ether group-containing alcohol according to claim 1, 2, 3, 4 or 5, wherein the ester conversion reaction is carried out while blowing molecular oxygen. Manufacturing method.