JPH0495054A - Production of acrylic acid or methacrylic acid alkylaminoalkyl ester and quaternary salt thereof - Google Patents

Abstract

PURPOSE:To obtain a high-purity quaternary salt in high yield by adding an alkylamino alcohol to a reaction system with time, reacting the alkylaminoalcohol with (meth)acrylic acid alkyl, distilling and purifying the prepared reaction product and gradually adding the reaction product and water separately to a quaternizing agent. CONSTITUTION:In subjecting a compound shown by formula I (R<1> is H or methyl R<2> is 1-4C alkyl) and a compound shown by formula II (R<3> is H or 1-8C alkyl; R<4> is 1-8C alkyl; R<5> is 1-4C chain saturated hydrocarbon group) to trans-esterification reaction, the reaction is carried out while maintaining concentration of the compound shown by formula II in the reaction system <=25mol%, especially 0.1-10mol% and occurrence of polymers of by-products of reaction is suppressed to form a compound shown by formula III. The compound shown by formula III obtained by distilling the reaction mixture and water are separately added gradually to a quaternizing agent in such a way that the amount of water added (wt.% based on accumulated amount of the compound shown by formula III and water added) is 0-35wt.% until the accumulated amount of the compound shown by formula III added reaches 50 total amount added and the amount of water added is 5-35wt.% when the accumulated amount of the compound shown by formula III is >=50wt to give a quaternary salt of the compound shown by formula III.

Description

[Detailed description of the invention]

[0001]

[Industrial application field]

The present invention relates to a method for producing alkylaminoalkyl esters of acrylic acid or methacrylic acid and quaternary salts thereof by transesterification. [0002]

[Conventional technology]

In general, alkylaminoalkyl esters of acrylic acid or methacrylic acid, such as dimethylaminoethyl acrylate, dimethylaminoethyl methacrylate, and diethylaminoethyl methacrylate, are used as they are, or when the amino group is converted into a tertiary or quaternary ammonium salt. Fiber dyeing improvers, plastic antistatic agents, pigment dispersants in paints, UV curing aids, toner binders, paints, lubricating additives, paper strength enhancers, adhesives, ion exchange resins, and cationic polymer aggregation. It is used as an agent, etc., and is useful in a wide range of fields. Among these, its use as a polymer flocculant is attracting attention, and it is usually used in the form of a quaternary salt. Quaternary salts are generally produced in the following three steps. (A) Synthesis reaction of alkylaminoalkyl ester (B
) Distillation purification of alkylaminoalkyl ester (C) Quaternization of alkylaminoalkyl ester. [0003] Step (A): A method for producing an alkylaminoalkyl ester of acrylic acid or methacrylic acid by a transesterification reaction between an alkyl ester of acrylic acid or methacrylic acid and an alkylamino alcohol is already known. Also,
It is known that this transesterification reaction tends to generate side reaction products. [0004] The reason why this side reaction product is likely to occur is that the alkylamino alcohol as a raw material has strong basicity, so that the alkylamino alcohol as a raw material and the alkyl alcohol to be produced may be alkyl esters of acrylic acid or methacrylic acid as raw materials, Another reason is that it is easy to cause a so-called Michael type addition reaction in which it is added to the double bond of the alkylaminoalkyl ester of acrylic acid or methacrylic acid produced. [0005] Another reason is that raw material alkyl esters of acrylic acid or methacrylic acid and alkylaminoalkyl esters of acrylic acid or methacrylic acid that are produced tend to polymerize with each other or themselves, leading to reactions and The problem is that polymers are likely to be generated during purification operations such as distillation. [0006] Therefore, the following two methods are currently known as methods for obtaining the target alkylaminoalkyl ester of acrylic acid or methacrylic acid with relatively high yield. [0007] One of them is a method using a catalyst that has a high selectivity for alkylaminoalkyl ester of acrylic acid or methacrylic acid and can reduce the generation of side reaction products. It is known that titanium alcolade, aluminum alcolade/magnesium alcolade, organotin compounds, zirconium compounds, zinc compounds/lead compounds, thallium compounds, etc. are used as this catalyst, and among them, organotin compounds have good selectivity. It is said to indicate. [0008] However, even in this method, the generation of side reaction products and polymers due to Michael type addition reactions cannot be sufficiently suppressed, and a satisfactory yield cannot be obtained. [0009] Another question is, does the above Michael type addition reaction and polymerization involve alkylamino alcohol in the reaction system? The higher the degree of A, the more likely it is to occur, so in order to lower the concentration of alkylamino alcohol, this is a method in which an excess amount of alkyl ester of acrylic acid or methacrylic acid is added to the alkylamino alcohol when charging the raw materials. [0010] However, this method has the problem that the volume of the reactor used increases, and the productivity of the reactor deteriorates. [00113 Step (B): The reaction mixture obtained in the transesterification reaction contains unreacted substances and by-products, and if the next quaternization step (C) is carried out as it is, poor quality quaternary salts will be produced. Therefore, highly pure alkylaminoalkyl esters are usually obtained by distillation. However, since alkylaminoalkyl esters are unstable, losses due to polymerization and the like cannot be avoided. In order to minimize this loss and to shorten the distillation process, it is required that the reaction mixture obtained in step (A) has a small amount of unreacted substances and side reactants. [0012] Step (C): The fourth method for producing f&ammonium salt is as follows:
It is usually obtained by reacting an alkylaminoalkyl ester of acrylic acid or methacrylic acid with a quaternizing agent (Menschudkin reaction). At this time, a method using an organic solvent and a method using an aqueous solvent are known as the reaction solvent. [0013] Among these, the method of reacting in an organic solvent (JP-A-52-
27712, JP-A-52-148017, etc.), it is possible to extract the quaternary ammonium salt as high-quality crystals, but a filtration step is required after extraction from the reaction vessel, and Since the extracted crystals are extremely hygroscopic, sufficient care must be taken when handling them. Therefore, problems arise such as the complexity of the process and poor workability. Further, an organic solvent remains in the obtained quaternary ammonium salt, and when such a quaternary ammonium salt is used as a polymerization raw material, the residual organic solvent acts as a chain transfer agent and has an adverse effect. [0014] In addition, a method using a large excess of alkyl halide as a quaternizing agent instead of an organic solvent (Japanese Unexamined Patent Publication No. 63-2841
(see Publication No. 49) has also been proposed. However, in this case, the reaction product is viscous and cake-like, making it difficult to remove heat and stirring, and problems such as polymerization are likely to occur. Furthermore, since a large amount of alkyl halide is used, productivity is extremely reduced, resulting in a lack of practicality. [0015] On the other hand, in the case of a method of reacting in an aqueous solvent, the ester group of the alkylaminoalkyl ester is extremely susceptible to hydrolysis, and therefore the corresponding unsaturated acid ((
meth)acrylic acid) is produced as a by-product. This by-product unsaturated acid not only causes a significant decrease in the quality of the quaternized product, but also
It tends to accelerate the polymerization of the alkylaminoalkyl ester and its quaternary ammonium salt, causing unexpected polymerization during the quaternization reaction. [0016] In order to solve these problems, a method of conducting the reaction at a low temperature below room temperature and a method of reducing the amount of water solvent (see Japanese Patent Application Laid-Open No. 52-31017) have also been proposed. [0017] However, in the method of reacting at a low temperature, although the hydrolysis rate itself is significantly reduced, the quaternization rate is also significantly reduced, so it takes an extremely long time to complete the reaction, and it is not suitable for industrial use. This cannot be said to be a suitable method. In addition, the method of reducing the amount of water solvent also increases the viscosity of the reaction system as the reaction progresses, causing crystals of quaternary ammonium salt to precipitate.
The mixture becomes slurry-like or even cake-like, which increases the stirring load extremely and reduces the reaction rate, making it extremely difficult to complete the reaction. [0018] Furthermore, since mi-hydrolysis tends to occur at the early stage of the reaction,
A method has also been proposed in which a quaternary ammonium salt of an alkylaminoalkyl ester product is added at the initial stage of the reaction (see JP-A-52-31016). Although this method is effective in suppressing hydrolysis to some extent, it requires the addition of a large amount of quaternary ammonium salt, and the production efficiency is poor from an industrial perspective, so it cannot be said to be a suitable method. [0019] A method of carrying out the reaction while maintaining the pH at 6 to 9 (see Japanese Patent Laid-Open No. 127351/1983) has also been proposed. However, in this case as well, the amount of water solvent used is relatively large, and it cannot be said that the suppression of hydrolysis is sufficient. [0020] In any of the above-mentioned methods of reacting in an aqueous solvent, suppression of hydrolysis is insufficient, and a method for industrially obtaining a high-grade quaternary ammonium salt has not been found. is the current situation. [0021]

[Problem to be solved by the invention]

The present invention aims to solve the problems associated with the prior art as described above. In the method for producing aminoalkyl esters, highly pure alkylaminoalkyl esters of acrylic acid or methacrylic acid can be obtained in high yields, and there are no restrictions on the catalysts used, allowing the use of inexpensive catalysts with high reaction rates. It has high productivity for the reactor used, and can be polymerized even in purification operations by reaction and distillation.
A production method that does not cause gelation, and a quaternary ammonium salt of good quality when producing a quaternary ammonium salt by reacting these alkylaminoalkyl esters of acrylic acid or methacrylic acid with a quaternizing agent. The objective is to provide a method for obtaining the reaction quickly and without any trouble during the reaction. [0022]

[Means to solve the problem]

As a result of extensive research into these problems, the inventors of the present invention discovered that by adding the raw material alkylamino alcohol to the reaction system over time, it was possible to achieve a stable reaction while suppressing the generation of side reaction products. In addition, in the quaternization step, an alkylaminoalkyl ester is added to the quaternization agent, and the resulting quaternary ammonium salt is purified with the minimum necessary amount of water. It was discovered that by quickly dissolving it, hydrolysis can be suppressed and a high-grade quaternary ammonium salt can be obtained.
The present invention has now been completed. [0023] That is, the present invention provides an alkyl ester of acrylic acid or methacrylic acid represented by the general formula (1), and an alkyl ester of acrylic acid or methacrylic acid represented by the general formula (1).
2) In the method for producing an alkylaminoalkyl ester of acrylic acid or methacrylic acid by a transesterification reaction with an alkylamino alcohol,
This is a method of reacting while adding the alkylamino alcohol to the reaction system. Furthermore, after distilling and purifying the reaction mixture obtained by this method, when reacting this alkylaminoalkyl ester with a quaternizing agent to produce a quaternary ammonium salt, acrylic acid is added to the quaternizing agent. A method in which an alkylaminoalkyl ester of acid or methacrylic acid and water are separately added and reacted, and when the alkylaminoalkyl ester and water are sequentially added to the quaternizing agent, the amount of water added is Until the cumulative addition amount of the aminoalkyl ester reaches 50% of the total addition amount of the alkylaminoalkyl ester, the cumulative addition amount of the alkylaminoalkyl ester and water is 0 to 50%.
35% by weight Alkylaminoalkyl ester of acrylic acid or methacrylic acid and its quaternary ammonium salt, characterized in that the amount of 50% or more is 5 to 35% by weight based on the cumulative addition amount of the alkylaminoalkyl ester and water. This is a manufacturing method. [0024] The method of the present invention will be explained in detail below. [0025] Step (A): In the method of the present invention, an alkylaminoalconyl is added to an alkyl ester of acrylic acid or methacrylic acid, and the reaction is advanced by heating and stirring to obtain the target alkyl ester of acrylic acid or methacrylic acid. This method produces aminoalkyl esters. [0026] Specific examples of alkylaminoalkyl esters of acrylic acid or methacrylic acid in the present invention include dimethylaminoethyl (meth)acrylate, diethylaminoethyl (meth)acrylate, dimethylaminopropyl (
Examples include tertiary amino group-containing (meth)acrylates such as meth)acrylate, dimethylaminobutyl (meth)acrylate, and dibutylaminoethyl (meth)acrylate. [0027] For example, the transesterification reaction when producing dimethylaminoethyl acrylate using methyl acrylate and dimethylaminoethanol as raw materials is shown by the following formula. CH=CHC00CH+ (CH')N(CH2)20
H←→ CM =CHC00(CH)N (CH)+
In the CH30H transesterification reaction, the raw material alkylamino alcohol and the generated alkyl alcohol are added to the double bond of the raw material acrylic acid or methacrylic acid alkyl ester or the generated acrylic acid or methacrylic acid alkylaminoalkyl ester. , a so-called Michael-type addition reaction occurs, and various side reaction products are generated. Typical side reaction products include methoxypropionate methyl ester, methoxypropionate dimethylaminoethyl ester, dimethylaminoethoxypropionate methyl ester, dimethylaminoethoxypropionate dimethylaminoethyl ester, and the like. [0028] This Michael type addition reaction occurs more easily as the alkylamino alcohol concentration in the reaction system increases. In addition, side reaction products generated when raw material alkyl esters of acrylic acid or methacrylic acid and alkylaminoalkyl esters of acrylic acid or methacrylic acid produced polymerize with each other or themselves are also generated in the reaction system. Species with high alkylamino alcohol concentration tend to occur. In order to solve such problems, the method of the present invention, in which alkylamino alcohol as a raw material is added to the reaction system, can suppress side reactions such as Michael type addition reactions and perform stable reactions. [0029] In order to suppress the above-mentioned side reactions, the concentration of alkylamino alcohol in the reaction system is preferably 0.01 to 25 mol%. More preferably 0.05 to 15 mol%
, more preferably within the range of 0.1 to 10 mol %. The concentration of alkylamino alcohol in the reaction system refers to the concentration of alkylamino alcohol, alkyl ester of acrylic acid or methacrylic acid, alkylaminoalkyl ester of acrylic acid or methacrylic acid, alkyl alcohol, and various other substances in the reaction system. It is the percentage of the number of moles of alkylamino alcohol to the total number of moles of side reaction products. [0030] Alkylamino alcohol as a raw material does not need to be charged at the start of the reaction, but a portion may be charged at the start of the reaction. In this case, the concentration of alkylamino alcohol in the reaction system is 25 mol% or less, preferably 15 mol% or less,
More preferably, it is in the range of 10 mol% or less. [0031] The addition time of the alkylamino alcohol depends on the raw materials used, their amounts, and the pressure 1. Varies depending on temperature, catalyst, etc. The addition can usually be started at the same time as the reaction starts, and the concentration of alkylamino alcohol in the reaction system can be adjusted to 0.01 to 25%.
It is added so as to maintain the amount by mol%, preferably from 0.05 to 15 mol%, more preferably from 0.1 to 10 mol%. [0032] Examples of the alkylamino alcohol used in the present invention include dimethylaminoethanol, diethylaminoethanol, dipropylaminoethanol, dibutylaminoethanol, diethylaminoethanol, dihexylaminoethanol, dioctylaminoethanol, methylethylaminoethanol, and methylpropyl. Aminoethanol, methylbutylaminoethanol, methylhexylaminoethanol, ethylpropylaminoethanol, ethylbutylaminoethanol, ethylpentylaminoethanol, ethyl octylaminoethanol, propylbutylaminoethanol, dimethylamitubrobanol, diethylaminopropanol, dipropyl Examples include aminopropanol, dibutylaminopropanol, butylpentylaminopropanol, and L-butylaminoethanol. [0033] In the method of the present invention, the amount of the alkyl ester of acrylic acid or methacrylic acid used is preferably 1.2 to 10 mol per mol of the alkylamino alcohol used.
More preferably, it is in the range of 1.5 to 5 mol. [0034] The alkyl ester of acrylic acid or methacrylic acid may be added all at once at the start of the reaction, or may be added in portions, for example, may be added to the reaction system together with the alkylamino alcohol. can. [0035] Examples of the alkyl ester of acrylic acid or methacrylic acid used in the present invention include methyl acrylate,
Examples include methyl methacrylate, ethyl acrylate, ethyl methacrylate, normal propyl acrylate, normal propyl acrylate, normal butyl acrylate, and normal butyl methacrylate. In particular, it is preferable to use methyl ester or ethyl ester of acrylic acid or methacrylic acid. [0036] As the catalyst used in the method of the present invention, various commonly used catalysts can be used, such as titanium alcoholade, aluminum alcoholade, magnesium alcoholade, organotin compound, zirconium compound, zinc compound, Examples include lead compounds and thallium compounds. In particular, organic tin compounds such as dibutyltin oxide and dioctyltin oxide are preferred from the viewpoint of selectivity. [0037] Further, the amount of the catalyst used is in the range of 0.01 to 10% by weight, more preferably 0.02 to 5% by weight based on the total amount of the alkyl ester of acrylic acid or methacrylic acid and the alkylamino alcohol. % range. [0038] During the reaction, a polymerization inhibitor is usually added to prevent polymerization of the raw materials and products. Commonly used polymerization inhibitors include phenothiazine, hydroquinone, hydroquinone monomethyl ether, di(L-butyl)catechol, phenyl-β-naphthylamine, and paraphenylenediamine. One or more of these compounds are used in the reaction, and the amount used is in the range of 0.005 to 2% by weight, preferably 0.01 to 1% by weight, based on the total weight of the compound. [0039] In the method of the present invention, the reaction temperature is 40 to 150°C,
Preferably, the reaction can be carried out at a temperature in the range of 60 to 140°C. Further, the reaction may normally be carried out under normal pressure, but it can also be carried out under reduced pressure or increased pressure if necessary. [0040] Further, in the method of the present invention, it is also possible to use a solvent without using a solvent. When a solvent is used, an inert solvent that forms an azeotrope with the alkyl alcohol produced in the transesterification reaction is used, such as hexane, benzene, toluene, cyclohexane, and the like. [0041] In order to obtain the target alkylaminoalkyl ester of acrylic acid or methacrylic acid in high yield, it is desirable to exclude the alkyl alcohol produced in the transesterification reaction from the reaction system. Specifically, the alkyl alcohol can be removed from the reaction system by azeotropic distillation with the unreacted alkyl ester of acrylic acid or methacrylic acid, or if a solvent is used, by azeotropic distillation with the addition of a solvent. can. [0042] Step (B): After the reaction of step (A) is completed, the reaction solution is first distilled off under reduced pressure to distill off unreacted alkyl ester of acrylic acid or methacrylic acid to obtain the target product, acrylic acid or methacrylic acid. The alkylaminoalkyl ester of the acid is obtained. This target product is further purified by distillation. [0043] Step (C): The alkylaminoalkyl ester of acrylic acid or methacrylic acid obtained from step (B) is reacted with a quaternizing agent. [0044] Specific examples of the quaternizing agent in the present invention include methyl chloride,
Ethyl chloride, butyl chloride, methyl bromide, octyl bromide,
Examples include alkyl halides such as methyl iodide, aralkyl halides such as benzyl chloride and methylbenzyl chloride, and alkyl sulfates such as dimethyl sulfate and diethyl sulfate. Among these, methyl chloride is particularly preferred from an industrial standpoint. [0045] If the amount of the quaternizing agent used is less than 1.0 mol based on the alkylaminoalkyl ester to be reacted, the alkylaminoalkyl ester may remain unreacted, resulting in a decrease in the yield of the product or If it remains, it can be a factor in deteriorating quality, but on the other hand, if it is too much, productivity will deteriorate. Therefore, the amount of the quaternizing agent used is preferably 1.0 to 3.0 mol, more preferably 1.01 to 1.10 mol, based on the alkylaminoalkyl ester to be reacted. [0046] In the quaternization reaction in the present invention, an alkylaminoalkyl ester of acrylic acid or methacrylic acid and water are separately added to a quaternization agent and reacted. For example, after charging the quaternizing agent into an autoclave and bringing it to a predetermined temperature, the alkylaminoalkyl ester is added continuously or intermittently. As the reaction progresses, the quaternary ammonium salt precipitates, so the minimum amount of water necessary to dissolve it is added continuously or intermittently to dissolve it. At this time, if water is added too quickly, hydrolysis tends to proceed and impurities in the quaternary ammonium salt of the product increase. On the other hand, if the addition of water is too slow, the quaternary ammonium salt will precipitate and form a slurry, making it difficult to remove heat and stir. Furthermore, the alkylaminoalkyl ester is incorporated into the precipitate and the reaction is not completed, becoming an impurity and reducing the purity of the product. Therefore, the input amount of alkylaminoalkyl ester is 5
Water must be added before reaching 0%. In other words, the amount of water added is 0% relative to the cumulative amount of alkylaminoalkyl ester and water until the cumulative amount of alkylaminoalkyl ester added reaches 50% of the total amount added.
~35% by weight, and when the cumulative addition amount of alkylaminoalkyl ester is 50% or more, 5 to 35% by weight, preferably 10 to 30% by weight, more preferably 15 to 25% by weight.
is set to [0047] When the reaction temperature is 10° C. or lower, the reaction takes a long time, while when it is 70° C. or higher, the polymerization stability of the product decreases and gelation may occur. Therefore, 10 to 70°C is preferable,
From an industrial point of view, the temperature is particularly preferably 25 to 50°C. The method of the present invention has a higher reaction rate than other conventional methods and has fewer side reactions such as hydrolysis, so the reaction can be carried out even at low temperatures. [0048] In order to prevent the raw material alkylaminoalkyl ester and the produced quaternary ammonium salt from polymerizing, it is preferable to use a polymerization inhibitor. As the polymerization inhibitor, hydroquinone, hydroquinone monomethyl ether (hereinafter referred to as MEHQ), phenothiazine, t-butylcatechol, diethylhydroxylamine, etc. can be used, and usually 500 to 3000 ppm is used. [0049] By adding water, the reaction liquid becomes a uniform transparent liquid as the reaction progresses, usually resulting in a liquid-liquid suspension. After the reaction is completed, water is added so that the concentration of the quaternary ammonium salt becomes 60 to 85% by weight, and the quaternary ammonium salt aqueous solution is taken out. [0050] The obtained quaternary ammonium salt aqueous solution can be further purified, if necessary, by adsorption treatment using an ion exchange resin or activated carbon, or extraction treatment using an organic solvent. Additionally, chelating agents such as EDTA, pH adjusters, or other additives may be added. [0051] The quaternary ammonium salt obtained by the present invention can be polymerized by a conventional method. For example, it can be carried out by methods such as aqueous solution polymerization, emulsion polymerization, suspension polymerization, and precipitation polymerization. In this case, the quaternary ammonium salt can be polymerized alone or can be copolymerized with other alkylaminoalkyl esters. In particular, the free amine exceeds O and is 0.1% or less, and the acid value exceeds 0 and is 1.0 m
In the case of a quaternary salt of dimethylaminoethyl acrylate having a concentration of gKOH/g or less, a polymer or copolymer having a larger molecular weight than conventional quaternary salts can be obtained. [0052] The method of the present invention will be specifically explained below using Examples. [0053] The conversion rate, selectivity, and yield used in this example are defined as: Conversion rate (%) = (Reacted alkylamino alcohol (mol)/Used alkylamino alcohol (mol)) x 100 selection Rate (%) = (produced alkylaminoalkyl ester of acrylic acid or methacrylic acid (mol)/reacted alkylamino alcohol (mol)) x loo Yield (%) = conversion rate x selectivity/100. [0054]

【Example】

Add 53.5 g of dimethylaminoethanol to a 1-liter flask equipped with a stirrer, thermometer, and fractionator.
(0,6 mol) Methyl acrylate 516.5 g (6,
0 mol), 6.3 g of dibutyltin oxide as catalyst
, 2.9 g of phenothiazine was added as a polymerization inhibitor, and heated while stirring. After the start of retention, the reaction solution was analyzed at regular intervals to ensure that the concentration of dimethylaminoethanol in the reaction system was constantly between 0.1 and 20% relative to the total amount of dimethylaminoethanol, methyl acrylate, and their reaction products. 213.9 (2.4 mol) of dimethylaminoethanol was added to be within 10 mol%. The dimethylaminoethanol addition time was 4 hours. The relationship between the reaction time and the dimethylaminoethanol concentration in the reaction system is shown by the curve ■ in the graph of FIG. The produced methanol was distilled out as a methanol-methyl acrylate azeotrope at a reflux ratio of 5 to 5.0 while maintaining the top temperature of the fractionating column at 62 to 66°C. The reaction was completed in 5 hours, and analysis of the reaction solution revealed that the conversion rate of dimethylaminoethanol was 95% and the selectivity was 98%. Then,
The pressure was reduced to 100 mmHg to distill out methyl acrylate, and the pressure was further reduced to 25 mmHg, and the target product, dimethylaminoethyl acrylate, was distilled out at a top temperature of 76 to 77°C. The amount of acrylic acid dimethylaminoethyl ester obtained was 400.2 g, and the purity was 99.8%. Moreover, the yield is 93%. The residue in the reaction vessel after expelling the acrylic acid dimethylaminoethyl ester had a low viscosity, and no polymer could be confirmed by gel permeation chromatography analysis. [0055] Implementation Example A transesterification reaction was carried out in the same manner as in Example 1, using the same apparatus as in Example 1 and changing the amount of dimethylaminoethanol charged and added as shown in Table 1. The relationship between the reaction time and the concentration of dimethylaminoethanol in the reaction system is shown by curve II in the graph of FIG. The results are also shown in Table 1. [0056] Implementation 2 ↓ Using the same apparatus as in Example 1, as shown in Table 1, the charged amount and addition amount of methyl acrylate were changed to adjust the concentration of dimethylaminoethanol in the reaction system. A transesterification reaction was carried out in the same manner as in Example 1, except that dimethylaminoethanol was added at a concentration of 25 mol % or less. The results are also shown in Table 1. [0057] As is clear from the results of Example 3, the higher the alkylamino alcohol concentration in the reaction system, the lower the selectivity. [0058] Comparison system ↓Using the same equipment as in Example 1, as shown in Table 2, the amounts of dimethylaminoethanol and methyl acrylate and the amount of methyl acrylate added were changed to produce the same results as in Example 1. A comparison study with this example was made in which a transesterification reaction was carried out in a similar manner, and the entire amount of dimethylaminoethanol was charged at the start of the reaction, but no dimethylaminoethanol was added during the reaction. The results are shown in Table 2. [0059] In Comparative Examples 1 and 3, since the molar ratio of methyl acrylate to dimethylaminoethanol was low, many side reaction products resulting from Michael type addition reaction were generated, resulting in low selectivity. Furthermore, the viscosity of the residue in the reaction vessel after distillation was high, and gel permeation chromatography analysis also revealed that a large amount of polymer was present. In Comparative Example 2, the yield of acrylic acid dimethylaminoethyl ester was low for the reaction vessel, and the productivity was poor. Moreover, the selectivity is also not satisfactory. [00601 Example Σ Using the same apparatus as in Example 1, a transesterification reaction was carried out in the same manner as in Example 1, except that the raw material methyl acrylate was replaced with ethyl acrylate. The results are shown in Table 3. [0061] Transesterification was carried out in the same manner as in Example 1, except that the same equipment as in Example 1 was used, the raw material dimethylaminoethanol was replaced with diethylaminoethanol, and the target product was acrylic acid diethylaminoethyl ester. The reaction was carried out. The results are shown in Table 3. [0062] Implementation J- Transesterification was carried out in the same manner as in Example 1, except that the same apparatus as in Example 1 was used, methyl acrylate was replaced with methyl methacrylate, and the target product was dimethylaminoethyl methacrylate. The reaction was carried out. The results are shown in Table 3. [0063] In a flask with an internal volume of 1 liter equipped with a stirrer, a thermometer and a fractionator, 53.5 g of dimethylaminoethanol was added.
(0,6 mol) Methyl acrylate 516.5 g (6,
0 mol) 6.3 g of dibutyltin oxide as catalyst
, 2.9 g of phenothiazine was added as a polymerization inhibitor, and heated while stirring. After the start of retention, the reaction solution was analyzed at regular intervals to ensure that the concentration of dimethylaminoethanol in the reaction system was constantly between 0.1 and 20% relative to the total amount of dimethylaminoethanol, methyl acrylate, and their reaction products. 213.9 (2.4 mol) of dimethylaminoethanol was added to be within 10 mol%. The dimethylaminoethanol addition time was 4 hours. The generated methanol has a temperature at the top of the fractionation column of 62 to 66.
It was maintained at a temperature of 0.degree. C. and distilled out as a methanol-methyl acrylate azeotrope at a residual ratio of 0.5 to 5.0. The reaction was completed in 5 hours, and analysis of the reaction solution revealed that the conversion rate of dimethylaminoethanol was 95% and the selectivity was 98%. Then, the pressure was reduced to 100 mmHg to distill off methyl acrylate, and the pressure was further reduced to 25 mmHg.
The target product, acrylic acid dimethylaminoethyl ester, was distilled out at a top temperature of 76 to 77°C. [0064] The obtained acrylic acid dimethylaminoethyl ester is 4
00.2 g, and the purity was 99.8%. Moreover, the yield is 93%. The residue in the reaction vessel after expelling the acrylic acid dimethylaminoethyl ester had a low viscosity, and no polymer could be confirmed by gel permeation chromatography analysis. [0065] Next, add 150 ml of methyl chloride to 1 liter of autoclave.
g (2.97 mol) was charged, stirring was started, and the internal temperature was maintained at 35°C, and the pressure was 7.1 kg/cm2.
It became. Then, 387 g of acrylic acid dimethylaminoethyl ester containing 2000 ppm of MEHo (2,
7 mol) was added dropwise at a rate of 64 g/hr. In parallel, 97 g of water was added at a rate of 16 g/hr. During this time, the reaction temperature was maintained at 35° C. and the reaction was allowed to proceed for 8 hours, and the pressure became 2.0 kg/cm 2 and the reaction solution became transparent. After the reaction was completed, 34 g of water was added to make an 80% by weight aqueous solution of quaternary ammonium salt. [0066] When the contents were taken out and analyzed, free amine 0.0
7%, acid value 0.5. [0067] Further, no polymerization was observed during the quaternization reaction. [0068] The free amine is ethylene glycol (EG)-isopropyl alcohol (IPA) (50:50 vol.
) Medium, 0. This value is calculated from the inflection point of the neutralization curve by titration with INKOH and is converted into the amount of alkylaminoalkyl ester, and the unit is weight %. Also, the acid value is E
In G-IPA (50:50 vol1%), 0.
The value is determined from the inflection point of the neutralization curve after titration with 1N HCl, and the unit is mgKOH/g. [0069] Note that the present invention is not limited to these above-mentioned embodiments. [00701

[Table 1]

July 00 [Table 2] [0072]

[Table 3] [0073] In the table, alkylamino alcohols are those of Examples 5 and 7.
In Example 6, it is dimethylaminoethanol, and in Example 6, it is diethylaminoethanol. Alkyl esters of acrylic acid or methacrylic acid are
Example 5 uses ethyl acrylate, Example 6 uses methyl acrylate, and Example 7 uses methyl methacrylate. The alkylaminoalkyl ester of acrylic acid or methacrylic acid is acrylic acid dimethylaminoethyl ester in Example 5, acrylic acid diethylaminoethyl ester in Example 6, and methacrylic acid dimethylaminoethyl ester in Example 7. [0074]

Effects of the Invention According to the method of the present invention, highly pure alkylaminoalkyl esters of acrylic acid or methacrylic acid can be obtained in high yield. Furthermore, there are no restrictions on the catalyst used, and any catalyst that is inexpensive and has a high reaction rate can be used. Furthermore, the productivity of the reactor used is high, and there is no fear of polymerization or gelation during purification operations such as reaction and distillation. In addition, when quaternizing alkylaminoalkyl esters of acrylic acid or methacrylic acid, it can effectively suppress undesirable side reactions such as hydrolysis and polymerization, and produce high-quality quaternary ammonium salts with extremely few impurities in high yields. You can get it at

[Brief explanation of drawings]

FIG. 1 is a graph showing the relationship between the reaction time and the concentration of alkylamino alcohol in the reaction system in Examples 1 and 2 of the present invention.

【Document name】

[Time drawing

Claims (3)

[Claims] [Claim 1] General formula (1) ▲Mathematical formulas, chemical formulas, tables, etc.▼(1) (In the formula, R^1 is a hydrogen atom or a methyl group, and R^2 is an alkyl group having 1 to 4 carbon atoms. acrylic acid or methacrylic acid alkyl ester represented by the general formula (2) ▲ Numerical formula, chemical formula, table, etc. ▼ (2) (In the formula, R^3 is a hydrogen atom or a carbon number of 1 to 8 , R^4 is an alkyl group having 1 to 8 carbon atoms, and R^5 is a chain saturated hydrocarbon group having 1 to 4 carbon atoms). A method for producing an alkylaminoalkyl ester of acrylic acid or methacrylic acid, characterized in that the reaction is carried out while adding the above alkylamino alcohol to the reaction system. 2. The concentration of the amino alcohol in the reaction system during the transesterification reaction is constantly 25 mol% or less based on the total amount of the ester of acrylic acid or methacrylic acid, the alkylamino alcohol, and the reaction products thereof. 2. The method for producing an alkylaminoalkyl ester of acrylic acid or methacrylic acid according to claim 1. [Claim 3] (A) General formula (1) ▲ Contains mathematical formulas, chemical formulas, tables, etc. ▼ (1) (In the formula, R^1 is a hydrogen atom or a methyl group, and R^2 is a carbon number of 1 to 4. esters of acrylic acid or methacrylic acid represented by the general formula (2) ▲ ▲ Numerical formulas, chemical formulas, tables, etc. ▼ (2) (in the formula, R^1 is a hydrogen atom or a carbon number of 1 to 1) 8 alkyl group, R^4 is an alkyl group having 1 to 8 carbon atoms, and R^5 is a chain saturated hydrocarbon group having 1 to 4 carbon atoms). General formula (3) ▲ Numerical formulas, chemical formulas, tables, etc. are available ▼ (3) When obtaining the alkylaminoalkyl ester of acrylic acid or methacrylic acid, the reaction is carried out while adding alkylamino alcohol to the reaction system. Step (A) of obtaining a mixture, (B) Step (B) of distilling the reaction mixture obtained in step (A) to obtain an alkylaminoalkyl ester represented by general formula (3), Step (C) The general formula obtained in B) (
The alkylaminoalkyl ester represented by 3) and water are separately added sequentially to the quaternizing agent, and when adding sequentially, the amount of water added is the upper limit of the cumulative amount of the alkylaminoalkyl ester and water. The lower limit is 35% by weight of the total amount of alkylaminoalkyl ester added.
A process of obtaining a quaternary ammonium salt of an alkylaminoalkyl ester by sequentially adding within the range of 0% until reaching 50%, and 5% by weight based on the cumulative addition amount of the alkylaminoalkyl ester and water. (C) A method for producing a quaternary salt of an alkylaminoalkyl ester of acrylic acid or methacrylic acid, the method comprising: