JP2003064137A - Method for producing polycarboxylic acid-based copolymer for cement dispersant - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing an esterified product by which the esterified product having high quality is efficiently produced with preventing generation of gel-like products generated in distilling off a dewatering solvent after an esterification reaction. SOLUTION: This method for producing a polycarboxylic acid-based copolymer for cement dispersants is to obtain an alkoxypolyalkylene glycol mono(meth)acrylic acid-based monomer (a) by esterifying (meth)acrylic acid with the alkoxypolyalkylene glycol in the presence of the dewatering solvent and acting an antigelling agent to a distillate containing the dewatering solvent during distilling the dewatering solvent after the esterification is finished and copolymerize 5-98 mass% alkoxypolyalkylene glycol mono(meth)acrylic acid- based monomer (a), 95-2 mass% (meth)acrylic acid-based monomer (b) and 0-50 mass% other monomer copolymerizable with those monomers (c) [here, the sum total of (a), (b) and (c) is 100 mass%].

Description

Description: TECHNICAL FIELD [0001] The present invention relates to a method for producing an esterified product.
It relates to a manufacturing method. Specifically, in a dehydrated solvent,
Esterification reaction between alcohol and (meth) acrylic acid
After the esterification reaction, the dehydration solvent is distilled off.
High quality (meth) acrylates
(Also simply referred to as esterified product in this specification)
This is a good manufacturing method, especially when the manufacturing equipment is operated continuously.
When industrially mass-producing esterified products by
Production method for highly efficient esterified products
It is. [0002] The present invention also relates to a method for producing the same.
Of Polyester for Cement Dispersant Using Waste Ester
The present invention relates to a method for producing an acid copolymer. [0003] A cement dispersant, calcium carbonate, car
Pigment dispersants such as Bon Black and ink, scale prevention
Agent, gypsum / water slurry dispersant, CWM dispersant, thickening
(Meta) used as raw materials for polymer components used in chemicals
Acrylic ester-based monomer components are
(T) obtained by an esterification reaction with acrylic acid;
It is. In such an esterification reaction, the reaction product water
As a by-product, do not remove this reaction water from the reaction system.
(Ie, when the reaction water accumulates), the equilibrium reaction
The reaction does not proceed in the direction of esterification
You. Therefore, when synthesizing the esterified product, a dehydrating solvent
Is distilled off (azeotropically) with the reaction product water.
The reaction product water is separated and removed, and the dehydrating solvent is refluxed to remove
After the completion of the reaction, the dehydrated solvent is distilled off,
A method of removing from the reaction tank containing stealide is taken.
ing. Such a manufacturing method is disclosed in, for example,
In Comparative Examples 1 and 2 of JP-A-9-328346, a reactor
(Separable flask) with thermometer, stirrer and water separation
Reactor equipped with a reactor to separate the reaction water
In addition, methacrylic acid and methoxy polyethylene as raw materials
Glycol (average number of moles of added oxyethylene group: 10
Mol), sulfuric acid (Comparative Example 1) or
Enesulfonic acid (Comparative Example 2), pheno as a polymerization inhibitor
Charge thiazine, cyclohexane as dehydrating solvent and stir
And cyclohexane-water azeotrope under normal pressure.
Distillation and cyclohexane while removing the reaction product water with a water separator
The esterification reaction is carried out by refluxing hexane,
After completion of the reaction, the used cyclohexane was distilled off,
A method for synthesizing an esterified compound is described. However, it is disclosed in the above-mentioned publication.
Thus, in the esterification reaction using a dehydrating solvent,
Except for distilling off the dehydrating solvent after completion of the reaction,
There have been reports on the technical issues, etc.
At present there is no such thing. SUMMARY OF THE INVENTION [0006] The present inventors dewatered water.
Efficient production of high-quality esterified products using chemicals
Distilling out the dehydrated solvent after the reaction in the course of the intensive research
When condensed and liquefied, a gel-like substance is formed.
When mass-producing esterified products by industrialization, the gel
The condensed matter is condensed and liquefied.
Adhering to the inner wall of the
This can lead to a decrease in heat exchange efficiency,
When operating continuously (in other words, continuously)
And the flow of fluid in the pipes (mainly liquid after condensation)
Operate regularly as it may lead to blockage.
Stop and wash the inside of the condenser and piping to remove the gel.
(2) Add water after the reaction to remove water
When the agent is distilled off azeotropically, the amount of water produced during the reaction is reduced.
Dehydration solvent reflux system used for separation and removal
This is repeated when the solvent is also used for solvent distillation.
(Continuous) operation (in other words, industrially large
Mass production) and part of the formed gel
Circulates dehydrated solvent during the esterification reaction in the next batch
Is taken into the dehydrated solvent when
By flowing, it stays as an impurity in the reaction tank,
Incorporated into the final product, such as cement
Dispersant, pigment dispersant, scale inhibitor, gypsum / water slurry
Performance, dispersant for CWM, dispersant for CWM, thickener, etc.)
It may be caused by gel-like material, such as
It has been found that many technical challenges arise. Accordingly, an object of the present invention is to provide an esterification
Solve the technical problems that arise when distilling off the dehydrating solvent after the reaction.
It is intended to provide a method for producing an esterified product.
You. Another object of the present invention is to provide the above-described technology.
Of gel-like material, which can be said to be the source of problems
Products and efficiently produce high-quality esterified products.
Providing a process for producing an esterified compound
It is. A further object of the invention is to provide a method according to the invention.
Therefore, S with low content of impurities (gel-like substance) produced
Cement with excellent cement dispersing ability using telluride
A method for producing a polycarboxylic acid copolymer for a dispersant.
Is what you do. Means for Solving the Problems Accordingly, the present inventors have
To solve the above problems, high-quality esterified
Intensive study on methods that can be manufactured efficiently
As a result, most of the gel-like substances generated when the dehydrating solvent is distilled off are
Poly (meth) acrylic acid, such a gel,
The esterification reaction between alcohol and (meth) acrylic acid
In order for the process to proceed efficiently, usually one material is overused.
To speed up the esterification reaction,
Excess of low-boiling materials that are easily distilled off
The low boiling point after the esterification reaction
The raw material at the point remains unreacted, and some of it is dehydrated.
Distilled with solvent (or azeotrope of dehydrated solvent and water)
When condensed and liquefied (gelled by liquid phase reaction)
The generation mechanism (source of generation)
Factor), and based on this, the gel-like
Find a solution that can prevent the occurrence of
The present invention has been completed based on the findings. That is, the objects of the present invention are as follows:
Can be achieved by the method described in (8).
is there. (1) In the presence of a dehydrating solvent, the following formula
(1): embedded image (Where R ¹ Is a char having 1 to 30 carbon atoms
Represents a hydrogen group, R ^Two O is an ox having 2 to 18 carbon atoms
Represents a silalkylene group, wherein each R ^Two Repeat O
The units may be the same or different,
And R ^Two When O is in the form of a mixture of two or more,
R ^Two O repeating units may be added in blocks.
Or n may be added randomly, and n is
Represents the average number of moles of oxyalkylene group added,
Alcohol (meta)
Method for producing esterified products by esterification reaction with lylic acid
In the method, after the esterification reaction, a dehydrating solvent is distilled off.
In the process, an anti-gelling agent is applied to the distillate containing the dehydrated solvent.
Characterized by comprising a step of reacting
Manufacturing method. (2) The anti-gelling agent contains a dehydrating solvent.
To operate in the area where the distillate is condensed.
The described method. (3) The anti-gelling agent condenses distillate
Above (1) or
The method according to (2). (4) The anti-gelling agent condenses distillate.
To work near the top of the condenser described in (3) above.
The method described. (5) Dehydration solvent after completion of the esterification reaction
Of dehydrating solvent by distilling azeotropically with water
Inside, the anti-gelling agent for the distillate containing the dehydrated solvent
(1) to (4) including a step of mixing and acting with water.
The method according to any one of (4). (6) The gelling inhibitor is water-soluble.
The method according to the above (5). (7) In the above formula (1), n is
Represents the average number of moles of the added alkylene group;
Described in any one of the above (1) to (6), wherein
the method of. (8) In the presence of a dehydrating solvent, the following formula: (However, R ¹ Is a char having 1 to 30 carbon atoms
Represents a hydrogen group, R ^Two O is an ox having 2 to 18 carbon atoms
Represents a silalkylene group, wherein each R ^Two Repeat O
The units may be the same or different,
And R ^Two When O is in the form of a mixture of two or more,
R ^Two O repeating units may be added in blocks.
Or n may be added randomly, and n is
Represents the average number of moles of oxyalkylene group added, 1-3
An alkoxypolyalkylene represented by the following formula:
Glycol undergoes an esterification reaction with (meth) acrylic acid,
During the dehydration solvent distillation step after the esterification reaction is completed
Then, an anti-gelling agent is produced for the distillate containing the dehydrated solvent.
Can be used to obtain alkoxypolyalkylene glycos
To obtain a mono (meth) acrylic acid monomer (a).
Lucoxy polyalkylene glycol mono (meth) acryl
5 to 98% by mass of a luic acid monomer (a), represented by the following formula (2): (Where R ^Three Represents a hydrogen or methyl group
And M ¹ Is hydrogen, monovalent metal, divalent metal, ammonium
(Meta)
95 to 2% by mass of acrylic acid monomer (b), and this
Other monomers (c) copolymerizable with these monomers (0 to 50)
% (Provided that the sum of (a), (b) and (c) is 10
0% by mass).
A method for producing a polycarboxylic acid copolymer for powder. DETAILED DESCRIPTION OF THE INVENTION According to a first concept, the present invention provides
In the presence of a dehydrating solvent, the following formula (1): (However, R ¹ Is a char having 1 to 30 carbon atoms
Represents a hydrogen group, R ^Two O is an ox having 2 to 18 carbon atoms
Represents a silalkylene group, wherein each R ^Two Repeat O
The units may be the same or different,
And R ^Two When O is in the form of a mixture of two or more,
R ^Two O repeating units may be added in blocks.
Or n may be added randomly, and n is
Represents the average number of moles of oxyalkylene group added,
Alcohol (meta)
Method for producing esterified products by esterification reaction with lylic acid
In the method, after the esterification reaction, a dehydrating solvent is distilled off.
In the process, an anti-gelling agent is applied to the distillate containing the dehydrated solvent.
Characterized by comprising a step of reacting
Is provided. In the present specification, “distillate” refers to a reaction
It means what is distilled from the tank (mixture).
As explained in detail, during the esterification
After the completion of the tellurization reaction process,
Regardless of the type, all distillate from the reactor is
Include. Therefore, the distillate according to the present invention
The state is not particularly limited, and is either gaseous or liquid.
May exist in a state. That is, in this specification
"Distillate" refers to the esterification reaction step unless otherwise specified.
Reaction product water, which is sometimes produced and distilled out of the reaction tank,
Sources that are distilled together when distilling the generated water from the reaction tank
Ingredients, especially (meth) acrylic acid, and further react as needed
Dehydration solvent added to the reaction tank to azeotrope with the generated water
Distillate containing; and removal after the end of the esterification reaction step.
A dehydrating solvent distilled off from the reaction tank during the water solvent distilling step, and
And the dehydrated solvent are distilled together when distilling out of the reaction tank.
Raw materials, especially distillates containing (meth) acrylic acid
Include. The reaction tank referred to here is not
Reactor, reaction vessel and reactor, etc.
Is used with the same meaning as
Something to be done. Below, for convenience of explanation,
May be used appropriately, but each individual has a narrow meaning.
The present invention should not be limited to the taste content. As well
In addition, both the condenser (condenser) and the water separator described later
Not to be bound by name
It is. In the first concept, the beauty treatment
Reaction of the dehydrating solvent during the dehydration
Since it is necessary to distill from the tank,
"Distillate" usually contains this dehydrated solvent,
Raw materials, specially distilled when the agent is distilled from the reaction tank
Containing (meth) acrylic acid. The method for producing the esterified product of the present invention is described below.
A preferred embodiment will be described step by step. The method for producing the esterified product of the present invention
In particular, in the present invention, an acid catalyst and a polymerization inhibitor
The alcohol represented by the formula (1) in a dehydrated solvent in the presence of
(Hereinafter also simply referred to as “alcohol”) and (meth)
Perform esterification reaction with crylic acid (esterification process
After the esterification reaction, complete the acid catalyst or acid catalyst
Part and (meth) acrylic acid partly neutralized (partial neutralization
After that, when the dehydrating solvent is distilled off (solvent removal step)
Then, an anti-gelling agent is produced for the distillate containing the dehydrated solvent.
It is desirable to use In the present invention, the esterification in a dehydrating solvent is carried out.
A step of distilling off the dehydrating solvent after the reaction, i.e.,
That is, the solvent distillation step is essential, and other
Process, for example, the esterification reaction (S
(Tellation step) and partial neutralization step are not particularly limited.
A similar method can be used, but the preferred mode of each step is as follows.
This is described below. Hereinafter, the method for producing an esterified product of the present invention will be described.
Embodiment of Esterification Reaction (Esterification Step)
Is briefly described below. First, the reaction system (reaction tank)
Alcohol and (meth) acrylic acid as raw materials, dehydration
Charge the solvent, acid catalyst and polymerization inhibitor, and mix these
Esterification at a constant temperature until the desired esterification rate is reached
Perform the reaction. Used as a raw material in the ester reaction according to the present invention.
The alcohol used is a compound represented by the following formula (1)
It is. Embedded image In the above formula (1), R ¹ Is a carbon atom
Represents a hydrocarbon group of Formulas 1 to 30. R ¹ Has 3 carbon atoms
When it is a hydrocarbon group exceeding 0, the alkyl group of the formula (1)
Esterified product of coal and (meth) acrylic acid, for example
For example, a copolymer obtained by copolymerizing with (meth) acrylic acid
The water-solubility of the product decreases, and the application performance, for example, cement dispersibility
Performance etc. decrease. Suitable R ¹ Range depends on the intended use
More different, for example, raw materials for cement dispersants
When used as ¹ Is one having 1 to 18 carbon atoms
Linear or branched alkyl and aryl groups
Is preferred. R ¹ Specifically, for example,
Group, ethyl group, n-propyl group, isopropyl group, n
-Butyl group, tert-butyl group, pentyl group, hexyl
Octyl group, nonyl group, 2-ethylhexyl group,
Decyl group, dodecyl group, undecyl group, tridecyl group,
Tetradecyl, pentadecyl, hexadecyl, f
Butadecyl, octadecyl, nonadecyl, eico
Alkyl such as sil group, heneicosyl group and docosyl group
Group; aryl group such as phenyl group; benzyl group, nonyl
Alkylphenyl group such as phenyl group; cyclohexyl
Cycloalkyl groups such as groups; alkenyl groups; alkynyl
And the like. Of these, cement dispersants
When used as a raw material, as described above, methyl
Group, ethyl group, propyl group, butyl group and phenyl group are preferred.
It is good. Further, R ^Two O has 2 to 18 carbon atoms, preferably
Preferably, it is an oxyalkylene group having 2 to 8 carbon atoms.
You. R ^Two O is an oxyalkylene having more than 18 carbon atoms
When it is a group, the alcohol of the formula (1)
The esterified product with acrylic acid is, for example, (meth) acrylic
The water solubility of the copolymer obtained by copolymerization with
The application performance, for example, the cement dispersing performance and the like is reduced. R
^Two As O, for example, an oxyethylene group, an oxypro
Pyrene, oxybutylene, oxystyrene, etc.
Of these, oxyethylene groups, oxy
Preferably, it is a propylene or oxybutylene group.
No. Also, R ^Two O repeating units may be the same.
Or may be different. Of these, R ^Two O repeat
When the units are different, that is, two or more different repetitions
In the case of having a repeating unit, each R ^Two The repeating unit of O is
Even if added in block form or added in random form
It may be. Further, n is 0 to 300, preferably 2 to 300.
A number of 300 and R ^Two O (oxyalkylene group)
Represents the average number of moles of repeating units. n exceeds 300
If possible, the compound of formula (1) and (meth) acrylic acid
And the polymerizability of the esterified compound is reduced. This average additional mode
The ester number obtained by the esterification reaction
The optimum range varies depending on the intended use of the
For example, when used as a raw material for cement dispersants
Has an average number of added moles n of preferably 2 to 300,
More preferably from 5 to 200, most preferably from 8 to 150
Is a number. When used as a thickener, etc.,
The average number of added moles n is preferably from 10 to 250, more preferably
Or 50-200. Also, when n = 0,
From the viewpoint of solubility in water and boiling point, ¹ Is charcoal
It is preferably a hydrocarbon group having 4 or more elementary atoms. You
That is, when n = 0 in the formula (1), particularly when methanol or
Alcohols such as tanol have a low boiling point,
Evaporates and dissolves in the produced water.
Part of the coal raw material is distilled out of the system,
This is because the yield of the chloride decreases. In the production method of the present invention, the above formula (1)
Use one kind of alcohol raw material represented by
Or in the form of a mixture of two or more.
No. A mixture of two or more alcohol raw materials represented by the formula (1)
The form of use in the compound is not particularly limited.
¹ , R ^Two At least one of O and n is different 2
Any form of use in a mixture of more than one kind is preferable, but it is preferable.
Is R ¹ Is composed of two types, a methyl group and a butyl group
Case; R ^Two O is oxyethylene group and oxypropylene
A group consisting of two groups; n is 1 to 10
And two of those of 11-100;
And a combination of-and-as appropriate. Use in the ester reaction according to the invention
(Meth) acrylic acid that can be
And methacrylic acid, even when used alone,
Or may be used as a mixture.
Any range can be employed. Used in the esterification reaction according to the invention
The mixing ratio of the above raw materials is stoichiometrically 1: 1 (molar
Ratio), but actually, alcohol and (meth) acrylic
As long as the esterification reaction with luic acid proceeds efficiently
Although it is not particularly limited, usually, one raw material is
Use in excess to speed up the esterification reaction or
From the point of purification of telluride, the lower boiling point
Use raw materials in excess. In the present invention, the esterification
When the reaction product water and the dehydrating solvent are azeotroped during the reaction,
Part of the (meth) acrylic acid is also distilled off and left outside the reaction system.
The amount of alcohol used (prepared amount)
Stoichiometric amount of (meth) acrylic acid
More than the theoretically calculated amount
No. Specifically, the amount of (meth) acrylic acid
Usually, 1.0 to 30 moles, preferably 1 mole, per mole of alcohol
Preferably 1.2 to 10 mol, more preferably 1.5 to 1
0 mol, most preferably 2 to 10 mol. (Meta)
The amount of acrylic acid used is 1.0 per mole of alcohol.
If it is less than the mole, the esterification reaction does not proceed smoothly,
The yield of the desired esterified product was insufficient,
If the amount exceeds 0 mol, the improvement in yield corresponding to the addition is observed.
Uneconomical and unfavorable. In the esterification reaction of the present invention,
May be performed by adding an acid catalyst to the reaction system, if necessary.
However, since the reaction can proceed promptly,
It is desirable to carry out the reaction in the presence of a catalyst. Use this time
Acid catalysts that can be used include, for example, sulfuric acid, meta
Sulfonic acid, p-toluenesulfonic acid, p-toluene
Sulfonic acid hydrate, xylene sulfonic acid, xylene
Sulfonic acid hydrate, naphthalenesulfonic acid, naphthalenesul
Sulfonic acid hydrate, trifluoromethanesulfonic acid, "Na
"fion" resin, "Amberlyst 15" cash register
, Phosphotungstic acid, phosphotungstic acid hydrate,
Hydrochloric acid and the like. At this time, the acid catalyst is used alone.
Used in the form of a mixture of two or more
Good. Of these, a dehydrating solvent described in detail below
Consider azeotropic temperature with water, esterification reaction temperature, etc.
And that the acid catalyst has a high boiling point at normal pressure
Is preferred. Specifically, it is preferably used in the present invention.
The boiling point of the acid catalyst at normal pressure is 150 ° C. or more, more preferably.
Or 200 ° C. or more. Therefore, sulfuric acid (at normal pressure
Boiling point: 317 ° C.), paratoluenesulfonic acid (boiling point:
185-187 ° C / 13.3Pa (0.1mmH
g)), paratoluenesulfonic acid hydrate and methanesulfur
Honic acid (boiling point: 167 ° C./1333.2 Pa (10 mm
Hg)) and the like are preferably used. Furthermore, the present inventor
Are responsible for the degradation of ester quality and performance.
One of the causes of the formation of diesters of impurities
By cleavage of the polyalkylene glycol,
Know that the cleavage could also be caused by an acid catalyst.
did. Based on such knowledge, the acid catalyst that is difficult to be cleaved
Is more desirable. Consider the above points
Then, an acid catalyst particularly preferably used in the present invention
Para-toluenesulfonic acid, paratoluenesulfonic acid
An example is folate hydrate. In the above embodiment, the amount of the acid catalyst used is
As long as the desired catalytic action can be exhibited effectively
Is not particularly limited, but is preferably 0.4
Reequivalent / g or less, more preferably 0.36 to 0.1 g / g.
01 meq / g, particularly preferably 0.32 to 0.05
Within the range of meq / g. 0.4 of acid catalyst used
When the amount exceeds milliequivalents / g, the reaction system
The amount of diester formed in
[Alkoxypolyalkylene]
Glycol mono (meth) acrylic acid]
The cement dispersing ability of the cement dispersant used is reduced. here
The amount of acid catalyst used (milli-equivalent / g)
Acid catalyst H ⁺ The equivalent number (milli-equivalent) of
Total charge of alcohol and (meth) acrylic acid (g)
It is expressed by the value divided by. More specifically, by the following formula
This is a calculated value. ## EQU1 ## In the present invention, the addition of an acid catalyst to the reaction system
The operation may be performed all at once, continuously, or sequentially.
From the viewpoint of workability, it is recommended to charge
Is preferred. Alternatively, in the present invention, in the presence of an acid catalyst
When the esterification reaction is carried out, the hydrate and / or
Alternatively, it may be used in the form of an aqueous solution. Acids that can be used in the above embodiment
As the catalyst, for example, sulfuric acid, methanesulfonic acid, para
Toluenesulfonic acid, xylenesulfonic acid, naphthalene
Sulfonic acid, trifluoromethanesulfonic acid, “Naf
ion "resin," Amberlyst 15 "cash register
Hydrate and / or phosphotungstic acid, hydrochloric acid, etc.
Or those used in the form of an aqueous solution.
Sulfuric acid, p-toluenesulfonic acid, methanesulfonic acid
Are used in the form of hydrates and / or aqueous solutions
Is preferably used. These can be used alone
Or two or more of them may be used in combination. Further
Meanwhile, the present inventors, as described above, the product of the esterified product
Of impurities diesters that cause degradation in quality and performance
One of the causes is due to the cutting of alcohol raw materials.
That the cleavage could also be caused by an acid catalyst.
And based on such knowledge, it is difficult to cut
It has been found that acid catalysts are more desirable. The acid
As the catalyst, specifically, paratoluenesulfonic acid is used.
Used in the form of hydrates and / or aqueous solutions
You. The amount of the acid catalyst used according to the above-described embodiment may be a desired amount.
As long as the catalytic action can be exhibited effectively,
Although not limited to
Control, various uses such as cement dispersant,
Pigment dispersion of lucium, carbon black, ink, etc.
Agent, scale inhibitor, gypsum / water slurry dispersant, CW
The raw materials of the polymer component used for the dispersant for M, the thickener, etc.
Usefulness as esterified products, such uses
Adversely affect the basic performance required for
High molecular weight crosslinked polymer with poor dispersing performance causing crushing
Consideration of prevention / suppression of gel formation which causes gelation
Then, the amount of the acid catalyst used and the alcohol used as the raw material (
(T) the quality of the acid in the acid catalyst relative to the total mass of acrylic acid
The ratio of the amounts is X (% by mass), and the hydrate and
And / or the mass ratio of water present as an aqueous solution
%), It is preferable to satisfy the following relationship: 0 <Y <1.81X-1.62. There is no misunderstanding
To explain with specific examples, for example, paratoluene
Take sulfonic acid monohydrate as an example.
X (mass%)
And exists as a monohydrate with respect to the total mass of the raw materials.
The ratio of the weight of the water to water is Y (% by mass).
And acid components other than the acid catalyst (for example,
Acrylic acid, etc.) and water (eg, by esterification reaction)
Generated water, etc.) are the X and Y objects referred to herein.
Can't be. At this time, the amount of the acid catalyst used is determined according to the above equation.
If not, the following problems occur. sand
That is, when Y = 0, the hydrate and / or
Or that there is no water present as an aqueous solution.
The amount of gel formed in the reaction system during the esterification reaction
Increases and the esterified product obtained by the esterification reaction
Performance of cement dispersant, etc., synthesized using
If this is the case, the cement dispersibility and the like will decrease. Also, Y ≧ 1.81
When it is X-1.62, a reaction occurs during the esterification reaction.
The amount of gel formed in the system increases,
Synthesized using the esterified product obtained
Deterioration of application performance of dispersant etc., for example, cement dispersibility etc.
I do. In the above embodiment, the addition of the acid catalyst to the reaction system
The addition may be performed all at once, continuously, or sequentially,
From the viewpoint of workability, charge all together with the raw materials into the reaction tank
Is preferred. The esterification reaction according to the present invention is indispensable.
If necessary, the reaction may be performed in the presence of a polymerization inhibitor. This
At this time, by using a polymerization inhibitor,
Of alcohol, (meth) acrylic acid or mixtures thereof
The esters according to the invention can be prevented from polymerizing
It is desirable to carry out the reaction in the presence of a polymerization inhibitor.
No. As the polymerization inhibitor that can be used in the present invention,
Known polymerization inhibitors can be used.
Phenothiazine, tri-p-
Nitrophenylmethyl, di-p-fluorophenylamido
, Diphenylpicrylhydrazyl, N- (3-N-O
Xyanilino-1,3-dimethylbutylidene) aniline
Oxide, benzoquinone, hydroquinone, metoquino
, Butyl catechol, nitrosobenzene, picrine
Acid, dithiobenzoyl disulfide, cuperon, copper chloride
(II) and the like. Of these, dehydrated solvents and raw
Phenothiazine, hydroxy,
Non and methoquinone are preferably used. These heavy
Inhibitors may be used alone or in combination of two or more.
It can also be used in combination. Further, as described above, the acid catalyst is
Phenothiazine when used in aqueous solution form
Reacts with the gel-forming substance in the aqueous solution present in the reaction system.
Can function effectively, as described later.
After the esterification reaction, the dehydration solvent is azeotropically mixed with water.
When distilling off more, a weak but high polymerization active
Do not use water-soluble polymerization inhibitors such as droquinone and methoquinone.
Can very effectively exhibit polymerization inhibiting ability,
Is it possible to effectively suppress the formation of high molecular weight substances?
It is extremely useful. According to the method of the present invention, a polymerization inhibitor is used.
The amount of polymerization inhibitor used in
To the total charged amount of phenyl and (meth) acrylic acid.
001 to 1% by mass, preferably 0.001 to 0.1% by mass
%. 0.001 quality of polymerization inhibitor used
If the amount is less than 10%, the polymerization inhibiting ability is not sufficiently expressed, and
Alcohol, (meth) acrylic acid, product and
Effective polymerization of esterified compounds or their mixtures
The use of polymerization inhibitors is undesirable because it is difficult to prevent
If the dose exceeds 1% by mass, the product esterified
Quality and performance due to increased amount of polymerization inhibitor remaining in
Unfavorable and excessive addition
It has no further effect and is preferred from an economical point of view.
I don't. Further, in the esterification reaction according to the present invention,
Therefore, it is necessary to carry out the esterification reaction in a dehydrating solvent.
And In the present specification, the term "dehydration solvent" refers to
It is defined as a boiling solvent. That is,
Generated by esterification reaction using water solvent
That can efficiently azeotropically generate reaction water
It is. Examples of dehydrating solvents include benzene and toluene.
, Xylene, cyclohexane, dioxane, pentane
, Hexane, heptane, chlorobenzene, isopropyl
And the like, alone or
Two or more can be used as a mixed solvent
You. Of these, the azeotropic temperature with water is 150 ° C. or less,
It is preferably in the range of 60 to 90 ° C.,
Specifically, cyclohexane, toluene, dioxane,
Benzene, isopropyl ether, hexane, heptane
And the like. Azeotropic temperature with water exceeds 150 ° C
In the case of handling, temperature control in the reaction tank during the reaction
And control of azeotropic condensate liquefaction, etc.)
Not preferred. The above-mentioned dehydrating solvent is combined with water produced by the reaction outside the reaction system.
Azeotropically, while condensing and liquefying the reaction water to separate and remove
It is desirable to reflux, and in this case, the amount of dehydrating solvent used
Of alcohol and (meth) acrylic acid as raw materials
1 to 100% by mass, preferably 2
５０50% by mass. Uses only one dehydrating solvent
If the amount is less than 10%, reaction products generated during the esterification reaction
The formed water cannot be sufficiently removed from the reaction system by azeotropic distillation,
It is not preferable because the equilibrium reaction of
If the used amount of the dehydrating solvent exceeds 100% by mass,
Effect cannot be obtained, and the reaction temperature
A large amount of heat is required to maintain a constant,
It is not preferable from a viewpoint. Further, in the esterification reaction according to the present invention,
Therefore, when a dehydrating solvent is used,
The reaction temperature is 30 to 130 ° C, more preferably 60 to 130.
° C, and the solvent circulation rate during the esterification reaction was 0.5
Cycle or more / hour, more preferably 1 to 100 cycles
It is desirable to set it to at least 1 hour / hour. This makes the reaction
Temperature is raised to the impurity formation temperature region (region over 130 ° C)
No need to react, impurities are formed in the reaction tank
Can be suppressed. Also, increase the solvent circulation speed.
The reaction water in the reaction tank for a long time
Azeotropic distillation from the reactor efficiently
Since the reaction proceeds in the direction of esterification, the reaction time is short.
It can be. In the present specification, the solubility during the esterification reaction
The agent circulation speed is defined as follows. You
In other words, the total amount (volume) of the dehydrated solvent charged in the reaction tank
On the other hand, during the esterification reaction, the dehydrating solvent in the
Recirculate from the reaction tank to the reaction tank again through the circulation path
As a result, it corresponds to the total amount of the dehydrated solvent charged in the reaction tank.
When the volume (volume) circulated is defined as one cycle
However, the circulation rate of the solvent during the esterification reaction is a unit time (1
Per hour), and
Is "cycle / time". So, for example
For example, in 5 hours, the total amount of the dehydrated solvent
Then, when the equivalent amount of 15 times is circulated,
Means that the solvent circulation rate is 3 cycles / hour. Similarly,
In 2 hours, based on the total amount of the dehydrated solvent charged in the reaction system,
Half of the equivalent amount (0.5 times) was circulated
Sometimes the solvent circulation rate is 0.25 cycles / hour.
You. Here, the dehydrating solvent in the reaction system is distilled from the reaction system.
Is circulated when it is condensed and liquefied and returned to the reaction system for circulation.
Objects (circulated objects) include, in addition to dehydrated solvents,
In some embodiments, a small but low boiling point
Raw materials (mainly (meth) acrylic acid raw materials)
Prevents raw materials from forming gels and becoming harmful impurities
Anti-gelling agent (polymerization inhibitor or
Various additives such as solvents containing polymerization inhibitors)
It is possible. Therefore, additives such as anti-gelling agents
If used, this will increase the solvent circulation rate
Conditions that take into account that it changes as the
Is preferably adjusted appropriately. The above reaction temperature and solvent circulation rate
Using the method (means) for heating the reaction tank and its apparatus
Temperature (calorific value) added to reaction tank and source to be charged into reaction tank
To the desired range depending on the amount of dehydrating solvent used, etc.
Can be adjusted. The reaction temperature is set in the reaction tank.
Is the maximum (MAX) temperature. That is, as heating means
Equipment used (eg, outer jacket, inner heater)
Temperature in the reaction vessel (reaction temperature)
Varies depending on the position, and the esterification reaction progresses.
Rise over time and fluctuate over time
However, an increase in the reaction temperature caused formation of impurities.
Regardless of location and time conditions,
And the time must not exceed the upper limit temperature specified above.
Is required here, so here
It has been decided. In the present invention, the esterification reaction is carried out in batch
Or in a continuous manner, but in a batch
Is preferred. The reaction conditions for the esterification reaction
Is a condition under which the esterification reaction proceeds smoothly.
The reaction temperature is 30 to 140 ° C, preferably 60 to 13 ° C.
0 ° C, more preferably 90 to 125 ° C, particularly preferably
Is 100 to 120 ° C. The above reaction temperature is
The conditions of the general esterification reaction of the present invention,
Azeotropically with the reaction water outside the reaction system, condensing the reaction water
When refluxing while liquefying and separating and removing, one example is
And falls within these ranges, but matches exactly
Not something. If the reaction temperature is lower than 30 ° C.,
The reaction does not proceed easily, and the reaction product water is dehydrated (distilled).
It takes time, and the reflux of the dehydrating solvent is slow, so
Therefore, the esterification reaction takes a long time.
It is not preferable. Conversely, the reaction temperature exceeds 140 ° C
And excessive amount of diester due to the cutting of alcohol raw material
Is generated to disperse cement,
Dispersion performance and thickening properties decrease. In addition, polymerization of raw materials
And the amount of raw materials mixed into the distillate increases.
Deterioration of performance and quality of certain esterified products,
After all it is not desirable. The reaction time is as described below.
At least 70%, preferably low esterification
Until it reaches 80%, but usually 1-50 hours
And preferably for 3 to 40 hours. Furthermore, the present invention
The esterification reaction is carried out under normal pressure or reduced pressure.
However, from the viewpoint of facilities, it is desirable to perform at normal pressure.
No. In the esterification reaction according to the present invention,
The tellurization rate is 70% or more, more preferably 70 to 99.
%, Most preferably 80-98%
No. If the esterification rate is less than 70%, the
The yield of sterilized compound was insufficient, and
Performance of cement dispersant, etc.
Dispersibility and the like decrease. Note that, as used in this specification,
Is the esterification measurement condition shown below.
To reduce the amount of alcohol, which is the starting material for esterification,
By measuring, the value calculated by the following formula
Is defined as ## EQU2 ## <Esterification Ratio Measurement Conditions> Analyzer: Waters Millennium Chromatography Manager Detector Detector: Waters 410 RI Detector Column: GL Science Inertsil ODS-2 3 Columns Temperature; 40 ° C. Eluent; 8946 g of water 6000 g of acetonitrile, 54 g of acetic acid were mixed and adjusted to pH 4.0 with a 30% by mass aqueous solution of sodium hydroxide. Flow rate: 0.6 ml / min The esterification rate was determined by the above formula.
Therefore, the esterification rate does not exceed 100%. Follow
Therefore, in the present invention, when the esterification rate exceeds
It is assumed that the esterification reaction has been completed at this point. As described above, the esterification step according to the present invention will be described.
The present inventors have explained that during the esterification reaction,
Distills off the generated water of reaction and contains the water of reaction
An anti-gelling agent is allowed to act on the distillate (here,
Is also referred to as the first embodiment).
I found it. As a result, the reaction product water in the reaction system is
While distilling out and condensing and liquefying, separating and removing,
Low boiling raw material that is distilled out of the reaction system with the water
Gels (poly) produced by certain (meth) acrylic acid, etc.
Effective prevention of (meth) acrylic acid, etc.
In other words, it is a source of product quality deterioration and equipment blockage, etc.
Can prevent the formation of contaminating gels
You. In a first embodiment, the esterification reaction
To act on the distillate such as water of reaction generated
The anti-gelling agent used for
Of low-boiling raw materials,
The polymerization reaction during the contraction stage can be suppressed,
Of gel generated at the riser flange, etc.
In other words, the condenser tube and the reaction tank and condenser
Especially if it can suppress the blockage of the connecting pipe between
It is not limited and has a similar purpose in the reaction system
It is not different from the polymerization inhibitor used.
Can be used in the same manner as described above,
Can be used by appropriately selecting from gelation inhibitors
You. Specific examples of the gelation preventing agent include, for example,
Enothiazine, tri-p-nitrophenylmethyl, di-
p-Fluorophenylamine, diphenylpicryl hydride
Razyl, N- (3-N-oxyanilino-1,3-dimethyl)
Tylbutylidene) aniline oxide, benzoquinone, ha
Idroquinone, methoquinone, butylcatechol, nitro
Sobenzene, picric acid, dithiobenzoyl disulfi
, Cuperon, copper (II) chloride and the like. these
Of these, phenolic
Thiazine, hydroquinone and methoquinone are preferably used
Is done. These anti-gelling agents may be used alone.
Alternatively, two or more kinds may be used in combination. The amount of the gelling inhibitor added is
Telling reaction conditions, especially the amount of heat added to the reaction system and
Depending on the amount of dehydrating solvent to be charged, etc.,
Equalization from the beginning, i.e. at the beginning of the distillation of the azeotrope
For low-boiling raw materials that are sequentially distilled until the end of the reaction,
The amount that can effectively prevent gel formation
Alcohol and (meth) as raw materials
0.1 to 1000 mass p based on the charged amount of acrylic acid
pm, preferably in the range of 1 to 500 ppm by mass.
By doing so, the above object can be achieved. Raw material preparation
If the amount is less than 0.1 mass ppm, the gel
May be formed, and es
For low-boiling raw materials that are distilled continuously until the end of the tellurization reaction,
Insufficient to always express polymerization inhibition effectively
It can be called quantity. On the other hand, 1000 mass based on the charged amount of raw materials
If the amount exceeds ppm, gel formation prevention (polymerization inhibition) ability
Is too much to effectively express
It is uneconomical because no further effects can be expected to match.
It should be noted that if all of the added amount is added at a time, the distillation of azeotropic
From the start of distillation to the end of the esterification reaction.
The formation of gels for low boiling raw materials
Because it is difficult to produce azeotropes,
Sequential from the start of azeotropic distillation to the end of the esterification reaction
(Continuously) Add a fixed amount at a time, and add
It is desirable to adjust the total to be within the above range. The action (action) of the above gelling inhibitor
Distilling out of the reaction system
Works effectively on the low-boiling raw materials (fluids)
As long as it can be touched)
For example, (a) gas before condensed and liquefied
And (b) a flocculant
May act on liquid distillates liquefied by
No. Also, both (a) and (b) may be used.
No. The preferred mode of action of the above gelling inhibitor is described below.
The method will be described with examples for each mode of operation.
Can combine these appropriately,
Other known methods of operation can be used as appropriate. What
In addition, the method of operation exemplified below will facilitate the present invention by those skilled in the art.
The typical ones can be
The present invention is not limited to these.
Needless to say, there is no. In a state where the gelling inhibitor is liquefied (dissolved),
How to make it work; charge in a suitable solvent, preferably in the reaction system
The anti-gelling agent is dissolved in the same type of solvent as the dewatering solvent.
The distillate containing water produced by the reaction (preferably
Agent-water azeotrope), specifically, the reaction product
Inside the condenser where the distillate containing water is condensed and liquefied
Of the condenser, preferably above the condenser (especially the tower)
(Near the top) so that it comes into parallel contact with the distillate
To be dripped or sprayed. In addition, the capacitor
Depending on the type, etc., a solution containing an anti-gelling agent
Gaseous distillate.
Contact with liquefied distillate
You may make it touch (compatibility or dispersion). further
In the above embodiment, the action site of the gelling inhibitor is located inside the capacitor.
Section, but in addition to the above parts,
Joint between flange and par line (flange)
And the flange between the vapor line and the top of the condenser tower
Thermometers and nozzles installed in the flanges of reactors, reactors, etc.
A part where gel is easily formed, such as a protrusion provided on the window
Position. Of these, the condensation inside the capacitor
Shrinking section (especially near the top of tower), standing of reaction tank and vapor
The flange line between the rising line and the vapor line
The flange between the top of the capacitor and the top
This is the site of action of the inhibitor. In addition, the above-mentioned action site is one place
It is not necessary to provide multiple places at the same time if necessary
You may. The gelling inhibitor is allowed to act in a solidified state.
Method: using a powder containing a gel containing an
A region for condensing effluent, specifically, water containing reaction product
Condenser inside the condenser where the distillate is condensed and liquefied
At the top of the condenser, especially near the top
Side) and into the condenser in parallel with the distillate
They are dropped or sprayed on the ground. In addition,
Prevents gelation of a certain particle size depending on the type of denser
Charge and load the agent inside the capacitor in advance
The contact may be made in advance. Further above
In some cases, the action site of the gelling inhibitor is
Although it was a contraction part, in addition to the above parts, the reaction tank and vapor
The joint (flange) between the rising line and the base
The flange between the perline and the condenser tower
For thermometers and viewing windows installed in flanges, reaction tanks, etc.
In areas where gel is likely to be formed, such as provided protrusions
You may. Of these, the condenser inside the condenser
(Especially near the top of the tower),
Flange and the vapor line and
Gelling inhibitor with a preferable flange portion between the top of the sensor tower
Is the site of action. In addition, the above-mentioned action site is one place.
May be provided, and if necessary, a plurality of locations may be provided at the same time.
Good. The gelling inhibitor is allowed to act in a vaporized state.
Method; vaporization (including sublimation) of the gelling inhibitor
Distillate containing gaseous reaction product water (low boiling point raw material
Before condensing and liquefying the reaction system (reactor)
For example, in the piping path communicating with the capacitor,
Internal condensing section (especially near the top), reactor and vapor
-The joint (flange) between the rising line and
Flange between vapor line and condenser tower top
Thermometers and peepers installed in flanges, reaction vessels, etc.
Areas where gel is easily formed, such as protrusions provided on windows
The condensing part inside the condenser (especially the top
Section), between the reaction tank and the vapor rise line
Between the flange and vapor line of the condenser and the top of the condenser tower
It is supplied to and mixed with the flange portion between them. In the present invention, the reaction tank and the vapor
Of the gel at the flange between the
If the purpose is to suppress the formation, prevent gelation
Supply only the dehydrating solvent to the flange without containing any
By doing so, the above object may be achieved. In addition,
In this case, specific examples of the dehydrating solvent are the same as those of the dehydrating solvent.
It is. In the above embodiment, the compound is used during the esterification reaction.
Use the same type of dehydrating solvent or
Supply some kind of dehydrating solvent to the flange, or
As detailed below, circulate the condensate (or part of it)
May be used. Also, in the absence of a dehydrating solvent,
When performing the oxidation reaction, a separate dehydration solvent supply mechanism is preferred.
Or near the flange to remove the dehydrating solvent
You only need to supply them. Further, among the above, the following will be described.
For reasons, it is better to adopt the above, especially for solvents
It can be said that it is better to work in a dissolved state. Sandals
In other words, when distilling reaction product water out of the reaction system,
In view of the above, it is desirable to be able to distill at a lower temperature. So
For this reason, a dehydrating solvent that azeotropes with the reaction water is charged to the reaction system.
During the reaction, the azeotrope of the dehydrating solvent and
Below, also referred to simply as a solvent-water azeotrope)
This is a common method. From this, low boiling raw materials
Acts quickly on the contained solvent-water azeotrope (ie,
Solvent-water azeotrope containing low-boiling materials condensed and liquefied
Low-boiling point that quickly contacts this liquefied substance and gels
Or compatible with the dehydrating solvent containing the raw material
So that the polymerization inhibitor can be appropriately dissolved.
Agents, especially those dissolved in solvents of the same type as the dehydrating solvent.
Is desirable. The above liquefaction, here in the dissolved state
When the anti-gelling agent is actuated in the
Solvents that can dissolve the agent include, for example, benzene
Zen, toluene, xylene, cyclohexane, aceto
, Methyl ethyl ketone, n-hexane, heptane, etc.
Preferably, as described above, the reaction system is charged.
It is preferable to use the same type as the dehydrating solvent to be charged. solvent
If a different solvent is used when returning the
If you collect them separately or return them to reflux
Means that the heat transfer coefficient of the mixed solvent is
If it becomes a coefficient, adjust the amount of heat added to the reaction system, etc.
The amount of distilled water (distillation rate) does not fluctuate significantly
Control management of the reaction system becomes complicated.
Use the same type of solvent used.
Is good. Further, the above-mentioned gelling inhibitor is added to a solvent (preferably
Or dehydration solvent) to prevent gelation
As the agent can suppress the generation of gel-like material,
Low boiling material (gas or liquefied) passing through the condenser
Product), there is always an anti-gelling agent and it works effectively
The gelling agent and the solvent may be
The mixing ratio is not particularly limited.
The antioxidant is usually added in an amount of 0.1 to 100 parts by mass of the solvent.
001 to 10 parts by mass, preferably 0.01 to 5 parts by mass
The ratio is such that it is added in the range. Mixing ratio is solvent 1
0.001 part by mass of the anti-gelling agent per 100 parts by mass
If full, the amount of anti-gelling agent used
A fixed amount based on the raw materials charged as specified
As a result, the amount of solvent used (total amount added) is large.
And the first dehydrated solvent is charged
The amount of solvent increases due to the
Adjust the calorific value, etc., and distill off the reaction product water (distillation rate)
It is necessary to ensure that the
Control management becomes complicated, and dehydration solvent and
If different solvents are used and separated and recovered,
Recovery costs increase and manufacturing costs increase. one
On the other hand, the mixing ratio prevents gelation with respect to 100 parts by mass of the solvent.
When the amount of the agent exceeds 10 parts by mass,
Since the amount (total amount added) is reduced,
And the frequency of contact with low-boiling materials is relatively low.
Drops and liquefies without contact to form a gel
It is difficult to effectively suppress this. Therefore, the unit
To ensure the required amount of addition per hour,
A large amount of anti-gelling agent more than specified above
Required, increasing manufacturing costs. In the present invention, the esterification reaction
Since the reaction is performed in a dehydrating solvent, the action of the gelling inhibitor
The reaction formation that occurs during the esterification reaction
Distilling water together with the dehydrating solvent, and distilling containing the reaction product water
Is condensed and liquefied, and the reaction product water is separated from the condensed liquefied condensate.
Is separated and removed.
Esterification while returning the condensed residue containing the agent to the reaction tank
When performing the reaction, a part of the condensed residue and the gelling inhibitor
The contained anti-gelling agent solution is allowed to act on the distillate.
(This embodiment is hereinafter referred to as “second embodiment”.)
Also referred to). This increases the amount of condensate remaining in the reactor
As much as possible and for distillate (especially for distillate
Wall of the condenser where the distillate condenses and liquefies, especially
Enough to wet the top wall well
Always supply an adequate amount of anti-gelling solution (capacitor
Down from the top of the tower). Therefore, the reaction tank
The reaction product water in the reactor is distilled from the reaction tank and then condensed and liquefied.
During the separation, low boiling water distilled off with the water of reaction
Always effectively prevent the formation of gel-like substances due to
And efficiently produce high-quality esulated compounds at low cost
It can be manufactured with. In the second embodiment, the
The effluent is usually the reaction product formed by the esterification reaction.
In addition to containing water, when distilling the reaction product water from the reaction tank
Raw materials distilled together, especially (meth) acrylic acid,
To the reaction tank for the purpose of azeotropic distillation with the reaction water as necessary
It contains the added dehydrating solvent. Needless to say, the present invention
In the description, the essential constituents of the present invention, the ester
The dehydration solvent is included during the dehydration solvent distillation step after the
The requirement for an anti-gelling agent to act on
The second embodiment, that is, formed during the esterification reaction
The reaction product water is distilled off together with the dehydrating solvent.
Is condensed and liquefied, and the reaction product water is separated from the condensate.
Solvent after separating and removing the reaction product water
While returning the condensed residue containing
When performing the reaction, a part of this condensed residue and the gelling inhibitor
A state in which the contained anti-gelling agent solution acts on the distillate
And / or the first embodiment, ie the ester
Of the reaction water generated during the
Including an embodiment in which an anti-gelling agent is allowed to act on the distilled distillate
It may be. Hereinafter, the second embodiment will be described. Gelling inhibitor used in the second embodiment
The solution is the solution acting on the distillate, more specifically the distillate
Low-boiling materials in the medium to prevent gelation
Solution containing part of the condensate and an anti-gelling agent
In this case, the anti-gelling agent is in the same form
Or in the form of a solution,
Preferably a part of the condensed residue and an anti-gelling agent in solution form
Is included. In this specification, the term “condensate”
"B" means the one coming out of the condenser outlet.
Further, according to the second embodiment, the gelling inhibitor solution is
For distillates such as reaction water generated during the sterilization reaction,
In such cases, the gel
An antioxidant solution is included in the condensate. And then moisture
The condensate is separated into condensate and separated water by a separator.
Both water and separated water are included in the definition of condensate,
They can be used independently of each other. Also, this specification
In the book, "part of the condensate" means simply the condensate
Apart from the partially separated ones, the condensate is obtained by separation
Condensate residue and part of the condensate residue. The “condensed residue” is separated by a water separator.
Refers to the component on the solvent side, and "separated water"
The component on the water side separated by a certain water separator. Components on the solvent side
As an anti-gelling agent solution, use as needed
Solvent and the like to be used. As a component on the water side
Include reaction product water and raw materials. The above capacitor
And a water separator according to the method for producing an esterified product of the present invention.
And is used as follows. That is, the book
In the method for producing an esterified product of the invention, the esterification reaction
Water generated in the reactor must be distilled from the reaction tank
However, the distillate contains components other than the reaction product water as described above.
Emissions into the atmosphere directly,
Because of the problems such as
After distilling from
It is necessary to make it. Then, it was distilled from the reaction tank
To the condenser (condenser) to condense and liquefy
Used to Further came out of the condenser outlet
What is sent to a water separator
Separated into layers, separated water consisting of components on the water side of one layer,
Separate into a condensed residue consisting of components on the solvent side of the other layer
Used to The above-mentioned condensate is added to the gelling inhibitor solution.
In addition to the above, the gelling agent described below (solution form
The same applies hereinafter), and other additives, for example,
Contains acid catalyst etc. which is added as appropriate for the purpose of replenishment in the reaction tank
It may be. As mentioned above, the anti-gelling agent may be any suitable
Dissolved in a solvent, preferably a solvent of the same type as the dehydrating solvent (or
Mixing, for example, dissolution of some anti-gelling agents in supersaturated state
If not included, use two or more anti-gelling agents
Some of the anti-gelling agent does not dissolve in the solvent
If it is contained, furthermore, the gelling agent is mixed
Is included). The anti-gelling agent used in the present invention
Low boiling point source that is distilled together with the reaction product water, etc.
Can suppress the polymerization reaction that occurs when the material is condensed.
There is no particular limitation as long as it can be done.
Appropriately selected from various known gelling inhibitors
The specific examples and preferable examples are described above.
This is the same as that for the anti-gelling agent. The amount of the gelling inhibitor used depends on the amount of distillate
From the start of distillation to the end of the esterification reaction.
Always effectively prevent gel formation for low boiling point raw materials
(Esterification from the start of distillate distillation)
(Integrated amount until the end of the reaction). Further
In the esterification reaction, using a dehydrating solvent, the dehydrating solvent
In the case of distilling and refluxing, the gelling inhibitor contains a distillate.
After achieving the purpose of preventing polymerization for
It is returned to the reaction tank in a state of being dissolved on the side of the condensed residue after removal,
It is gradually accumulated in the reaction tank. As a result,
Polymerization using the esterified product as a raw material and cement dispersion
Polymerization is difficult when manufacturing various products such as agents. Yo
Therefore, it is desirable to minimize the amount of gelling inhibitor used.
No. In view of the above, the amount of the anti-gelling agent used is
Total amount of alcohol and (meth) acrylic acid used
0.1 to 1000 mass ppm, preferably 1
５００500 ppm by mass. Use of anti-gelling agent
The amount is less than 0.1 ppm by mass based on the total amount of the raw materials used.
In this case, from the start of distillation of distillate containing reaction product water, etc.
Low-boiling raw materials that are distilled continuously until the end of the esterification reaction
Inadequate for always expressing the polymerization inhibiting ability effectively
Since the amount is insufficient, a gel-like substance may be generated. one
On the other hand, the total amount of raw materials exceeds 1000 ppm by mass
In this case, the excess
Is too small to produce additional effects commensurate with excessive addition.
In addition to being uneconomical due to lack of prospect, the resulting ester
Polymerized to produce various products such as cement dispersants.
Polymerization becomes difficult when manufacturing. Note that the use of gelling inhibitors
If the entire dose was added at one time, the fraction containing
Distillation from start of distillate to end of esterification reaction
Effective formation of gel-like material for incoming low-boiling materials
It is difficult to prevent this, so the amount of anti-gelling agent used
Should be added continuously within the range specified above.
No. At this time, gel is applied to low-boiling raw materials that are sequentially distilled.
The anti-gelling agent concentration in the anti-gelling agent solution is always specified as follows.
It is more desirable to adjust so that it is within the range and add it continuously.
New When the anti-gelling agent is used in the form of a solution,
Solvents that can be used are particularly limited
Instead, for example, benzene, toluene, xylene,
Chlohexane, acetone, methyl ethyl ketone, n-f
Xane, heptane and the like. Also, esterification
Use a dehydrating solvent and distill off the dehydrating solvent to reflux.
In this case, the solvent component used in the gelling agent
Since it is contained in the liquid side and returned to the reaction tank,
It must be able to function effectively as a dehydrating solvent in the reaction tank.
Is desirable. In particular, the dehydrated solvent charged in the reaction tank
If a different solvent is used, the amount of
(Concentration) is gradually increased, and the dehydrating solvent containing the solvent reacts with
The azeotropic point with the formed water (and the resulting distillation rate) with time
Control and control the amount of heat applied inside the reactor
In addition, as the number of raw materials increases,
Complicated or complicated overall quality control and inventory control
From the point of the same, the same type of dehydration solvent charged in the reaction tank
Solvents are more preferred. The main purpose of using the solvent here is to prevent gelation.
In the solution of the blocking agent, mixing with a part of the condensate becomes easy.
And a stirrer when mixing with a part of the condensate
(For example, a stirring tank) need not be provided.
It is to be. Then, a dehydrated solvent is used for the esterification reaction.
When the solvent is distilled off and refluxed,
To minimize the increase in the amount of condensed residue returned to the
Of the condensate (preferably condensate) used in the inhibitor solution
The higher the mixing ratio, the better.
It is desirable to minimize the amount used. From this perspective,
The concentration of the anti-gelling agent in the solution is determined based on the entire solution.
10 mass ppm to saturation concentration, preferably 100 mass
ppm to saturation concentration, more preferably 200 mass ppm to
Saturation concentration, particularly preferably 200 mass ppm to saturation concentration
(Corresponding to the gelled concentration)
May vary depending on the type of inhibitor and solvent, temperature, pressure, etc.
Because it is not determined in a specific way, specific numerical values are specified.
Not). By using a saturated solution, the solvent
Can be reduced as much as possible. In addition,
To keep the concentration of anti-gelling agent dropped from the densa
Is higher than the saturation concentration that changes with temperature.
Equivalent to 95% of the saturation concentration
It is preferable to use at a concentration below the required concentration. The above gelling inhibitor
When the concentration is less than 10 mass ppm with respect to the whole solution
Contains some of the condensate used in the gelling agent solution.
The ratio decreases, and a dehydrating solvent is used in the esterification reaction.
If the dehydrated solvent is distilled off and refluxed, it is returned to the reaction tank.
The amount of condensed residual liquid increases. Or the gradually increasing condensate residue
A large storage area that can be stored until the end of the esterification reaction,
A device for taking out part of the condensate from the system over time
Means are required. In addition, the amount of solvent used increases and costs increase
Be up. Further, the gel used in the gelling inhibitor solution
About flow rate (flow velocity) of antioxidant and condensate
Of the anti-gelling agent in the anti-gelling agent solution
Size and distillation of reaction equipment (reaction tank, piping, condenser, etc.)
Because it depends on the quantity of goods, etc.
No, but reduce the amount of anti-gelling agent
By using a sufficient amount of condensate, a sufficient amount of gelation can be prevented.
An inhibitor solution can be applied to the distillate,
Use a dehydrated solvent in the tellurization reaction and distill off the dehydrated solvent.
When flowing, minimize the increase in the amount of solvent in the reaction tank
Is determined appropriately according to the mode of use (regulation).
Fixed). For 1m diameter (inner diameter) of condenser
The flow rate per minute of the gelling inhibitor is 0.01 to 40.
Liter / min m, preferably 0.1-15 liter / min
m, more preferably 0.1 to 5 l / min m,
In addition, the condensed liquid per 1 m of the diameter (inner diameter) of the condenser
Some per minute flow rate is 1-1000 liter /
M, preferably 5 to 500 l / min m, more preferably
Or 10 to 200 liters / minute m. Gelling prevention
If the flow rate of the agent is less than 0.01 liter / min.
The concentration of the anti-gelling agent in the solution decreases, and sufficient polymerization is always prohibited.
It is difficult to develop the ability. On the other hand, gelation prevention
If the flow rate of the agent exceeds 30 l / min.
As the amount of solvent added increases the amount of anti-gelling agent
And using a sufficient amount of condensate instead
It is difficult to achieve the gist of the present invention. Also, the condensate
If some flow rate is less than 1 liter / min m, distillate
Can always supply a sufficient amount of condensate
It is not preferable because it may cause the generation of a gel-like material.
No. On the other hand, the flow rate of a part of the condensate is 1000 l / min.
If it exceeds m, supply at a higher flow rate than this
It is not possible to obtain a further effect corresponding to this large amount of condensate
Equipment to supply at high flow rates (large pumps and large diameter
It is necessary to provide
You. As described above, depending on the use mode, gelation prevention
Determine (prescribe) the flow rate of the agent and a portion of the condensate, preferably
After determining (prescribed) the flow rate of a part of the condensate residue,
The combination must be within the specified flow rate range.
It is possible to do everything, but to fully demonstrate the gist of the present invention
Is condensed with the anti-gelling solution used for the anti-gelling agent
The mixing ratio with a part of the liquid is preferably the following combination. One part by weight of the condensate is
Parts by mass from 0.5 to 10,000 parts by mass, preferably from 1 to 100 parts by mass.
0 parts by mass, more preferably 10 to 1000 parts by mass, especially
Preferably it is in the range of 10 to 100 parts by mass. Gelling prevention
Part of the condensate is less than 0.5 part by mass per 1 part by mass of the blocking agent
In the case of, the above-mentioned gist of the present invention should be sufficiently satisfied.
Is not preferred. On the other hand, 1 part by mass of the gelling inhibitor
On the other hand, when part of the condensate exceeds 10,000 parts by mass
Is because it is difficult to mix both stably.
You. In addition, even if these mixing ratios are constant or
It may be variable so as to satisfy the above-described gist of the present invention.
The mixing ratio may be appropriately determined. In the present invention, the action of the gelling inhibitor solution
Distillates, especially distillate low boiling point
That can effectively act on the fee
For example, the method is not particularly limited.
Step) can be performed as appropriate. Preferably gaseous
A region where the distillate of the above is condensed and liquefied, specifically, a gaseous
There are heat exchangers and coolers, which are areas where the distillate is condensed and liquefied
Or a condenser or the like (in this specification, these are collectively referred to simply as
Condensation and liquefaction of gaseous distillate
At the gas inlet at the top of the condenser,
To enable the anti-gelling agent solution to work effectively
desirable. For that, an anti-gelling solution is present
The area is not limited to the inside of the condenser, near the top of the condenser
Beside, that is, the top of the condenser or immediately before the condenser
The anti-gelling agent solution in the distilling route of
In doing so, the inner wall of the capacitor is always wet
It is desirable to be able to keep As a specific example,
Nozzle installed upward at the center of the top of the condenser tower
From the inner wall of the gas inlet at the top of the condenser (here
First condensed and liquefied, and at the same time gelled low-boiling raw materials
Was sprayed with an anti-gelling agent solution.
Blow, blow, spray, discharge, blow
Raise or lower the inner wall of the capacitor
To keep it wet, or
The previous distilling route (a process formed by a pipe 503 in FIG. 2 described later)
(Nozzle section) in the overhead line)
3), where the anti-gelling agent solution is sprayed (or sprayed).
Start) Conden along the overhead line wall
The inner wall of the capacitor is always wet by reaching
Method to keep the condition, but are not limited to these.
It is not done. In addition, dewatering of the esterification reaction
When an agent is used and the dehydrating solvent is distilled off and refluxed,
When distillate is condensed and liquefied, it quickly contacts this liquefied material
Dehydrating solvent containing low-boiling raw materials
Gel so that it can be compatible or dispersed in
The anti-gelling agent dissolves the anti-gelling agent in the same type of solvent as the dehydrating solvent.
Preferably, it is used in unraveled form. Further, a part of the condensate is converted into a gelling agent solution.
The method of refluxing for use is not particularly limited.
Instead of using a conventionally known method (means) as appropriate.
be able to. Specific examples are shown below. (1) Use of a dehydrating solvent for the esterification reaction
When the dehydrated solvent is distilled off and refluxed, the condensed residue
When returning to the reaction tank, a part of the condensed residue
It is directly supplied to the nozzle portion, and the gelling agent is
Solution or during supply to the nozzle
And mixed with an anti-gelling agent to form an anti-gelling agent solution
You can do things. A specific example is shown in FIG.
As described above, the condensed residue is removed from the reaction tank (preferably,
Back to the flange between the upper riser line)
If necessary, temporarily store residual condensate on the path.
Storage part (tank, etc.) is provided, and
Part was extracted and extracted to the anti-gelling agent supply path
Gestures that are easily mixed just by joining a part of the condensate
Antioxidant solution. Because of that
A device for mixing and stirring the two is unnecessary. here
The merit of providing a storage part is that
Increase the amount of condensate remaining
Condensation is convenient when adjusting and returning to the reaction tank
The amount of residual liquid is not always constant from the start to the end of the reaction
It is easy to adjust the recirculation while minimizing the increase
It is possible. In addition, new storage units such as storage tanks
For example, in a water separator,
The condensed liquid condensed and liquefied by the air is stored in one chamber,
And the solvent phase are separated into two layers.
The solvent phase in the upper layer is separated
Overflow the board and store it in the other room next to it
However, if the chamber where only this solvent phase is stored is enlarged,
The separator itself can also serve as a storage unit (see FIG. 4).
See). However, the storage is not always necessary.
When compared to the conventional gelling inhibitor alone,
If an anti-gelling solution containing condensed residue is used
Therefore, the amount of anti-gelling agent is the same as or less than conventional
A large amount of gelation can be effectively prevented by the amount.
For this reason, the increase in the amount of solvent in the reaction tank is about the same as before.
Or a small amount. Especially the esterification time
When the reaction time is short, the decrease in the reaction temperature is small and
It is more economical not to have a storage unit because it has less impact.
This is also advantageous. It is also returned to the reactor
When the amount of solvent increases and increases,
The agent may be taken out of the system without returning. Also in this case,
The amount of solvent drawn out of the system is not large,
Is less economical than providing a storage unit.
Because it does not affect the performance of the product
It is. In this way, performance impact and cost effectiveness
Considering the results, it may be appropriate to decide whether to provide a storage unit
It can be said that it is essential. (2) Esterification reaction without using dehydrating solvent
When distilling is carried out, the distillate is essentially the reaction water (slightly
(Including low-boiling materials), and some of the distillate
Does not reflux. Therefore, gelation of distillate is prevented.
Reaction water (low boiling point)
Total amount of condensed residue separated and removed
And supply it directly to the nozzle section.
And, at the nozzle portion, a gelling agent solution, or
Mixing with the anti-gelling agent during the supply to the nozzle
To form a gelling inhibitor solution. In addition,
If a part of the condensed residue is used, the remaining condensed residue
It can be extracted. Note that the above-described method for operating
The method of refluxing is only a typical example.
However, the present invention is not limited to these. In the above, the esterification process according to the present invention
The esterification reaction according to the present invention has been described in detail.
When the reaction is performed in the presence of an acid catalyst and in a dehydrating solvent,
After the completion of the sterilization reaction, the acid catalyst described below or
Neutralizes all of the acid catalyst and some of the (meth) acrylic acid
It is desirable to perform a partial neutralization step. That is, the present inventor
Are used in the step of removing the dehydrating solvent after the esterification reaction.
Azeotropy with the addition of
After the ester reaction, conditioned water is added for further polymerization.
When producing an aqueous solution of the esterified product
Hydrolysis by the acid catalyst occurs, and the quality of the esterified product and
In addition to the degradation of performance,
Below, also simply referred to as hydrolysis products)
Remaining, using the esterified product such as cement dispersant
A place to synthesize polymers used for various dispersants, thickeners, etc.
In this case, the hydrolysis product is an impurity not participating in the polymerization.
And the polymerization rate (and thus productivity) decreases,
This will lead to deterioration of coalescence quality and performance.
In order to solve the problem, the esterification process
After completion of the oxidation reaction, neutralize the acid catalyst with alkali at 90 ° C or less.
It has been found that it is desirable to do so. to this
In the process after the esterification reaction,
High purity and high quality esterified product without
Obtainable. Here, a preferred embodiment of the partial neutralization step
This will be described below. In the partial neutralization step of the present invention, the esterification reaction
After completion of the reaction, the temperature is 90 ° C or less, preferably in the range of 50 to 0 ° C.
The acid catalyst is neutralized with an alkali. The neutralization temperature (in the reaction system)
(Liquid temperature) exceeds 90 ° C,
Acts as a catalyst for hydrolysis, increasing the amount of hydrolysis products.
It is not preferable because it is generated in an amount. In addition, 5
Below 0 ° C, alkali acts as a catalyst for hydrolysis.
And the generation of hydrolysis products is completely suppressed.
Can be. On the other hand, when the temperature is lower than 0 ° C.,
The reaction solution becomes viscous, making stirring during neutralization difficult.
It takes a long time to cool down to the specified temperature after the esterification reaction.
And to lower the temperature below room temperature,
It is necessary to provide a new cooling means (equipment).
Not so desirable In addition, the above-mentioned partial neutralization step
Possible alkalis (neutralizing agents) are particularly limited
Instead of hydroxide M (OH) _n In the form of water
Any substance that dissolves and shows basicity may be used.
Is an alkali metal, alkaline earth metal or ammonium group
To In addition, alkali metal carbonates and phosphates,
Monia, amine, and the like are also included in the alkali. Yo
As the alkali, specifically, for example, hydroxylated
Hydroxidation of alkali metals such as sodium and potassium hydroxide
Materials, magnesium hydroxide, and alkali hydroxides such as calcium hydroxide
Hydroxides of lithium earth metals, ammonia, amines, etc.
However, when it is mixed with cement,
For reasons of alkali metal or alkaline earth gold
Hydroxides, carbonates, phosphates and the like. In addition, the present invention
In the above, one or more of these alkalis may be appropriately used.
You may mix and use by ratio. The acid to be neutralized with the above alkali is an acid catalyst
Medium, preferably all of the acid catalyst and one of the (meth) acrylic acid
Department. Here, the neutralized (meth) acrylic acid is
Ten properties of (meth) acrylic acid used in the esterification reaction
% Or less, preferably in the range of 0.01 to 5% by mass.
You. Therefore, the addition amount of the alkali (neutralizing agent) is
1.0 to 100 equivalents, preferably 1.0 to 100 equivalents
It is 10 equivalents, more preferably 1.01 to 2 equivalents.
The reason why the acid to be neutralized is an acid catalyst is as described above.
The catalyst reacts strongly with water added after the esterification reaction
And deactivate the acid catalyst to produce hydrolysis products
This is because it is necessary to In addition, as the acid component,
(Meth) acrylic acid may be present in addition to the acid catalyst.
Since the catalyst has a higher acid strength, it is neutralized from the acid catalyst
No problem. Therefore, if the acid catalyst can be neutralized,
Can be achieved, but the difference in the type of acid catalyst actually used
(= Difference in acid strength)
In this case, the (meth)
Because some of the lylic acid may be neutralized,
From the viewpoint of eliminating danger (risk), the total amount of acid catalyst
Part of the (meth) acrylic acid may be neutralized. However,
The neutralized (meth) acrylic acid is used in the esterification reaction.
When it exceeds 10% by mass of (meth) acrylic acid used
Probably indicates that the polymerization rate of (meth) acrylate
Ta) The ester obtained is slower than acrylic acid.
Is preferred because the polymerization rate when polymerizing with
I don't. The amount of alkali (neutralizing agent) added depends on the amount of acid catalyst.
When the amount is less than 1.0 equivalent to 1 equivalent, the acid catalyst is completed.
Not fully neutralized, producing a large amount of hydrolysis products
Is not preferred. Conversely, addition of alkali (neutralizing agent)
When the amount exceeds 100 equivalents per equivalent of the acid catalyst,
Also neutralized a large amount of (meth) acrylic acid,
Polymerization rate of (meth) acrylate is (meth) acrylic acid
Is slower than
It is not preferable because the polymerization rate at the time of combining decreases. The form of the added alkali is
Is not particularly limited, but the
The form prevents hydrolysis of the esterified product
It can be said that it is preferable from a viewpoint. Particularly, the esterification reaction is carried out in a dehydrating solvent.
Therefore, a large amount of water is added to the reaction system together with the alkali.
However, it is preferable to prevent hydrolysis of the esterified product.
is there. That is, in a reaction system without a large amount of water, alkali
Is suspended in the system in a dense state because it is hardly soluble in dehydrating solvents
And the suspension of this highly concentrated alkali until it is consumed for neutralization.
Hydrolysis of the esterified product does not disappear over the long-term
cause. The amount of water added depends on the form of use of the alkali.
Although it depends, for example, a 40-60% aqueous alkaline solution is
When added as a wetting agent, separate from the aqueous alkali solution
In general, 5 to 10 parts by mass of the aqueous alkali solution is used.
00 parts by mass, preferably 10 to 100 parts by mass. This
If the amount of water added is less than 5 parts by mass,
For this reason, the alkali becomes non-uniform in the reaction system,
The alkali causes hydrolysis of the esterified product, and
When the amount exceeds 00 parts by mass, to secure the productivity
Higher costs, such as the need for a separate neutralization tank
I don't. Next, the solvent distillation step which is a characteristic part of the present invention is described.
The process will be described below. That is, in the present invention,
Since the esterification reaction is performed in a dehydrated solvent,
After performing the oxidation process, the dehydrating solvent is distilled off from the reaction solution.
Things. Further, the above esterification reaction is carried out in the presence of an acid catalyst
When performed under the above esterification step
After performing the oxidation reaction, acid catalyst by the partial neutralization step,
Furthermore, neutralize a part of (meth) acrylic acid,
The dehydrating solvent is distilled off from the reaction solution. According to a preferred embodiment of the solvent distillation step,
This will be described below. In the solvent distillation step of the present invention, the esterification reaction
After completion of the reaction (partial neutralization as necessary), dehydration
When distilling off the solvent, the distillate containing the dehydrated solvent
The present invention is characterized in that a polymerization inhibitor is caused to act.
Thereby, after the esterification reaction, the dehydrating solvent is distilled off.
Low boiling point mixed in the distillate containing the dehydrating solvent
Gel-like material produced by raw material (meth) acrylic acid
(Poly (meth) acrylic acid, etc.)
High purity and high quality esterification
You can get things. In this case,
The product usually contains a dehydrated solvent,
Raw materials that are distilled together when distilling, especially (meth)
It contains crylic acid. In the present invention, after completion of the esterification reaction,
The dehydrating solvent is distilled off, and the distillate containing the dehydrating solvent is
The anti-gelling agent used for the action
Unreacted low-boiling raw materials contained in the effluent are condensed and liquefied
If it can suppress the polymerization reaction that occurs at the stage
Is not particularly limited, and various gellings conventionally known
It can be used by appropriately selecting from the inhibitors. Book
Specific examples of the anti-gelling agent that can be used in the invention include:
Include, for example, phenothiazine, tri-p-nitrophen
Nilmethyl, di-p-fluorophenylamine, dife
Nilpicrylhydrazyl, N- (3-N-oxyanily
No-1,3-dimethylbutylidene) aniline oxide,
Benzoquinone, hydroquinone, methoquinone, butylca
Tecol, nitrosobenzene, picric acid, dithioben
Zoyl disulfide, cuperon, copper (II) chloride, etc.
I can do it. Due to its solubility in dehydrating solvents and water, pheno
Thiazine, hydroquinone and methoquinone are preferably used
Is done. These polymerization inhibitors may be used alone
In addition, two or more kinds can be used as a mixture. In this case, the amount of the gelling inhibitor used (addition amount)
Addition) as the distillation temperature (calorific value) and the esterification reaction.
The amount of dehydrating solvent used (and
Of unreacted low-boiling raw materials depending on the amount of water obtained)
Amount corresponding to the output amount, that is, distillation of distillate containing dehydrated solvent
Distillation from start of dispensing until dehydration solvent is sufficiently distilled off
Gel-like material for unreacted low-boiling raw materials
Act in an amount that can effectively prevent the formation of
The alcohols of formula (1) and (meth)
(T) The amount of acrylic acid is usually 0.1 to the used amount (prepared amount).
1 to 1000 mass ppm, preferably 1 to 500 mass p
pm. 0.1 mass p based on the amount of raw materials used
If it is less than pm, a gel may be formed,
Sufficient dehydration solvent from the start of distilling of distillate containing dehydration solvent
Unreacted low-boiling source, which is distilled sequentially until distilled off
In order to always exhibit the polymerization inhibition ability effectively,
That's enough. On the other hand, 100
When the amount exceeds 0 mass ppm, polymerization inhibition ability is effectively generated.
It is too much to show and is worth the excess
It is uneconomical because further effects cannot be expected. In addition, use
If the entire amount of the anti-gelling agent is added at once,
Dehydration solvent is sufficiently distilled from the start of distillation of distillate containing chemicals
To unreacted low-boiling raw materials that are sequentially distilled until
And it is difficult to effectively prevent gel formation
Of the amount of dehydrating solvent contained in the distillate over time
At the beginning of distillation of distillate containing dehydrated solvent
Until the dehydrating solvent is sufficiently distilled off.
Add the required amount, and the total final addition amount is within the above range.
It is desirable to make adjustments. Making the above-mentioned gelling inhibitor act on distillate
As for the method (the mode of action and the area to be acted on)
For unreacted low boiling raw materials (fluids) distilled out
If it can be effectively acted on (contact),
However, for example, (a ′) condensed liquefaction
May act on gaseous distillates prior to
And (b ′) reacting with the liquid distillate liquefied by the coagulation liquefaction.
You may make it act. In addition, (a ′) and
Both of (b ′) may be used. Hereinafter, the preferred action of the above gelling inhibitor will be described.
How to do this will be described with examples for each mode of operation.
In the present invention, it is possible to appropriately combine these.
Or any other known method of operation can be used as appropriate.
You. It should be noted that a person skilled in the art can perform the operations exemplified below.
Representative examples so that the present invention can be easily understood.
The present invention is not limited to these.
It goes without saying that it is not done. (1 ′) A gelation inhibitor is mixed with a liquid (solvent).
Solution), a method of acting in a state where it has been dissolved;
Solvent, preferably a solvent of the same type as the dehydrating solvent used in the reaction
Or water) mixed with an anti-gelling agent to make it liquid
(Although they may be simply dispersed,
Is preferable), and distillate containing dehydrated solvent (preferred)
Or the azeotropic distillate of dehydrating solvent and water)
Condensed and liquefied distillate containing dehydrated solvent
Where condensation takes place, for example inside a condenser
The upper part of the device, preferably a condenser,
(Near the top) so that it comes into parallel contact with the distillate
To be dripped or sprayed. Also, condensing and liquefaction equipment
Depending on the type and type of storage,
Keep the liquid inside a device such as a condenser.
Gaseous distillate or liquefied distillate
Pour in and contact (compatible or dispersed)
It may be. Further, in the above embodiment, the production of the gelling inhibitor is controlled.
Although the part for use was inside the capacitor, in addition to the above part,
Junction between reactor and vapor rise line
(Flange) or vapor line and condenser tower top
Installed in the reaction tank, etc.
Gels such as thermometers and projections provided on viewing windows
It may be a site that is easily formed. Of these,
Upper part of DENSA (especially near the tower top), reactor and vapor
Flange and vapor line between the
The flange between the component and the top of the condenser is preferably
This is the site of action of the antioxidant. In addition, the action site is
It does not have to be a single location.
May be provided. (2 ') The gelation inhibitor is prepared in a solidified state.
Method: use a powdery anti-gelling agent
The area where the distillate is condensed and liquefied, specifically, a dehydrating solvent
For condensing and liquefying distillate containing distillate, eg,
For example, the inside of a capacitor
The distillate from the top of the unit (especially the top)
Dropping or spraying so that they come into parallel contact with
It is. Also, depending on the type and type of equipment such as capacitors
Therefore, the anti-gelling agent of the specified particle size is
Load or load inside the equipment such as
May be brought into contact. Further in the above embodiment
Even the action site of the anti-gelling agent was inside the capacitor
However, in addition to the above parts, the reaction tank and vapor rise
Joints (flanges) between lines and vapor lines
Such as the flange between the capacitor and the top of the condenser
Thermometers and viewing windows installed in sections, reaction vessels, etc.
It may be a part where gel is easily formed, such as
No. Of these, the upper part of the condenser (especially near the tower top)
Side), the flow between the reactor and the vapor rise line
Between the flange or vapor line and the top of the condenser tower
The flange is the preferred site of action of the gelling inhibitor.
In addition, the above-mentioned action site does not have to be one place,
Accordingly, a plurality of locations may be provided at the same time. (3 ') The gelation inhibitor is prepared in a vaporized state.
Method of vaporizing the anti-gelling agent (including sublimation)
And a distillate containing gaseous condensed and liquefied
(Including low-boiling materials)
Equipment used for distilling (eg, for esterification reactions)
It is desirable to use the reactor used as it is).
In a piping path that communicates with a condensing and liquefying device such as a condenser.
It is supplied and mixed. Note that, among the above (1 ') to (3'),
For the reason explained below, it is better to adopt the above (1 ').
I can say that. In other words, from an economic perspective and handling
It is necessary to distill and remove the dehydrating solvent from the surface at a lower temperature.
Desirable methods for this include, for example,
(Particularly, in the partial neutralization step,
If treated with an aqueous solution, a large amount of water is
(This water may be used)
Is an effective means. Dehydration using appropriate amount of water
When distilling off with a solvent (azeotropic), the aqueous phase also has a low boiling point
Ingredients are transferred and distilled along with water,
In the distillate that gradually evaporates as the
The proportion of water solvent decreases, and eventually almost water (low boiling point)
(Including raw materials) will be distilled, resulting in gelation
Insufficient effect cannot be obtained even if the inhibitor is dissolved in the solvent
From the above, according to the method (1 ′), the gelling inhibitor is
It is desirable to work with water, especially water-soluble
Water-soluble anti-gelling agent using water
It is more desirable to dissolve and act. Sa
Are effective for distillates containing unreacted low-boiling raw materials.
(Ie distillate containing low-boiling raw materials)
When this is condensed (liquefied), it quickly contacts this liquefied material
Liquefied material containing low-boiling raw materials
(Compatible with or dispersible in (water and organic solvents))
To obtain distillate by the method of (1 ') above.
Water and / or solvent according to the component composition
It is desirable to act on what is dissolved in the. For example,
Do not monitor changes in the composition of distillate over time with sensors, etc.
In addition, the gelling inhibitor composition to be acted on (for example,
Dissolve in a solvent, preferably a dehydrating solvent
Of a gelling inhibitor composition that dissolves in water
(Mixing ratio) may be changed, and
The antioxidant is dissolved in a dehydrated solvent and dissolved in water.
The anti-gelling agent can be dissolved in water by different routes.
Each spray installed in the equipment such as condenser
Dropping or spraying from nozzle
Is desirable. Also, the above (1 ') is adopted.
The reason is that the anti-gelling agent per unit mass
The more liquid used, the more this gelation will be prevented
Liquid mixed with an agent is liquefied and condensed by one of means (= heat exchange medium)
There is also the advantage that it can act as a body). Here, an anti-gelling agent dissolved in water
Water-soluble gelation that can be used when
Examples of the inhibitor include hydroquinone, methoquinone
Etc. are preferably used. On the other hand, an anti-gelling agent dissolved in a solvent
Dissolve the above gelling inhibitor when acting
Solvents that can be used, for example, benzene, toluene,
Xylene, cyclohexane, acetone, methyl ethyl ke
Ton, n-hexane, heptane and the like.
Or the same type of dehydration solvent used in the esterification reaction
It is better to use That is, if different solvents are used,
In order to collect and reuse these mixed solvents separately,
Separation and purification must be performed in multiple stages, which is necessary for reuse
Costs are higher, and disposable
You. However, such disposable mixed solvent disposal
Wastewater after incineration or dilution to below environmental standards
Processing, etc.) requires a certain cost
Air pollution, water pollution, etc.
Going back to creating a well-known earth-friendly environment
Will be. On the other hand, when using the same type of dehydrating solvent
Can be reused at low cost through simple processing.
Therefore, it can be said that it is excellent in cost and environment. In the present invention, the gelling inhibitor is a liquid (water
And / or solvent)
In order to suppress the generation of gel,
Low-boiling material (gas or liquefied
Product), there is always an anti-gelling agent and it works effectively
The gelling agent and the liquid may be
The mixing ratio is not particularly limited,
(A) In the case of dissolving in water to act, 100 mass of water
0.001 to 10 water-soluble gelling inhibitors per part
Parts by mass, preferably in the range of 0.01 to 5 parts by mass,
When dissolved in a solvent to act, 100 parts by mass of the solvent
0.001 to 10 parts by mass of an anti-gelling agent
Or in the range of 0.01 to 5 parts by mass. Water 100
0.001 mass of a water-soluble gelling inhibitor based on mass parts
Less than 100 parts by weight or gelation prevention for 100 parts by weight of solvent
If the amount of the agent is less than 0.001 parts by mass, low boiling in the distillate
Efficiently uses a suitable concentration of anti-gelling agent for point raw materials
As a result, it may be difficult to make contact. Also,
The amount of liquid per unit mass of anti-gelling agent increases,
Processing costs such as disposal after distilling out of the system together with the dehydrating solvent
Increases, which is economically disadvantageous. On the other hand, water 100
More than 10 parts by weight of a water-soluble gelling inhibitor based on parts by weight
Or an anti-gelling agent per 100 parts by mass of the solvent
Exceeds 10 parts by mass, the amount of liquid used (
The total amount added during the evaporation of the water solvent)
Low boiling point with limited amount of addition per unit time and unit volume
The frequency of contact with raw materials is relatively reduced, and liquid
It is difficult to effectively suppress the formation of gels
become. Therefore, it is necessary to
In order to secure the added amount, a large amount of
The necessity of an anti-oxidation agent increases the production cost. What
In the case where water and solvent are used together
In the case of (a) and (b) above,
These sums are large without being bound by the specified range.
It is around the range specified in (a) to (b) above
Thus, it may be adjusted appropriately. In the solvent distillation step, the esterification in the system is
Solvent from solution containing debris and dehydrated solvent
To the equipment mechanism from the condensate liquefaction to removal outside the system
In this regard, a method for allowing the gelling inhibitor to act during this time
Any restrictions provided that a step (device mechanism) is provided
Instead, combine appropriately known device mechanisms.
Can be. For example, in the esterification step described above,
During the esterification reaction, the dehydrating solvent in the reaction system
Used to distill and condense and liquefy the water
Part of the equipment mechanism (simply called a solvent circulation device)
Can be used, and the equipment can be simplified and downsized.
Therefore, it can be said that this is one of the desirable embodiments. Specifically,
Is a device for condensing and liquefying distillate
For solvent etc., the previous solvent circulation device can be used as it is,
Liquid-liquid separation, a device for separating and removing condensed and liquefied distillate
For the water separator, etc., which is an
It can be used by changing the usage form. That is, the distillate
Liquid transported to the water separator according to the component composition
Route and transport device for removing distillate of water out of the system
Using a pump, etc.
Not only can all of the excretion be removed from the system,
Attach a vacuum pump (ejector) to the water separator, etc.
By suction, select components with relatively high volatility
Or remove all liquid distillate out of the system.
It may be. Alternatively, distillate condensed and liquefied
A separate transportation route is provided from the
To waste treatment equipment and recycling equipment)
And can be disposed of appropriately (discarded or reused)
You. These devices also have appropriate control mechanisms.
It is desirable that In addition, the device exemplified above
Instead of the mechanism, the dehydrating solvent in the system is distilled and
Unless it deviates from its original purpose of being removed outside,
Combination with other means and devices known in the art
Or by other means and alternatives to the device
It is needless to say that can be appropriately adopted. In the solvent distilling step, esterification is performed.
After the completion of the reaction (if necessary,
Solvent) containing esterified products and dehydrating solvent in the system.
There are no particular restrictions on the method used to remove the dehydrating solvent from the liquid.
Not dehydrated using water as described above.
May be distilled off by azeotropic distillation with other suitable additives
May be added to effectively remove the dehydrating solvent.
Without using any additives (including water),
Can be removed by removing
Therefore, it is extremely useful to use an acid catalyst (that is,
Even if you consider that you have to partially neutralize
It can be said that the utility is extremely high.)
And it is preferable to distill and remove by azeotropic distillation with a dehydrating solvent.
It can be said that this is one of the embodiments. Note that the process up to the solvent
When partial neutralization of acid catalyst is performed,
In a solution containing esterified products and dehydrating solvent
Has no active acid catalyst or alkali (neutralization to salt)
The hydrolysis reaction occurs even when water is added and the temperature is raised.
To avoid this, azeotrope with water when distilling off the dehydrating solvent.
Can be In addition, it is lower than azeotropic with water
It can remove dehydration solvent efficiently at temperature.
is there. In the solvent distillation step according to the present invention, the system
Conditions for distilling the dehydrated solvent from the solution of
Can distill (evaporate) the dehydrating solvent in the system
There is no particular limitation as long as it is possible.
As the temperature in the system during the removal of the agent (the temperature of the liquid in the system (under normal pressure))
For example, when (1 ″) water is used, it is usually 80 to
120 ° C., preferably 90-110 ° C., (2 ″)
When not using water, usually 80-160 ℃, preferably
Is 90 to 150 ° C. The above (1 ") or (2")
In any case, a temperature lower than the temperature specified above
Temperature, a temperature (heat) sufficient to evaporate the dehydrating solvent
Amount), but it takes a long time to evaporate the dehydrating solvent.
On the other hand, if the temperature is higher than the temperature specified above,
In some cases, there is a risk of polymerization and a large amount of heat
Is not preferred because it is consumed in the evaporation of the low boiling point raw material. Ma
The pressure in the system (inside the equipment) is either normal pressure or reduced pressure.
Although it may be performed at normal pressure, it is desirable to perform
Good. In addition, the solvent is distilled from the solution containing the dehydrated solvent.
The equipment used for the esterification reaction
It is better to use the installation system (reaction tank) as it is. Sandals
After the ester ester reaction, the contents were separately transferred to another device and changed.
Equipment and management costs will increase,
Esterification etc. are external factors (heat, light, transport temperature, transport
Pressure, active atmosphere gas), etc.
Or stick to the transportation route, or
It is necessary to prevent elution or contamination of impurities
This is not preferred because extra costs are incurred. In the esterification step, (meth)
In the presence of a polymerization inhibitor to prevent the polymerization of acrylic acid,
If an esterification reaction is performed, the polymerization inhibitor
Is after the esterification reaction (and after the partial neutralization)
Function effectively, the system
There is no need to replenish the polymerization inhibitor in the solution inside
However, a partial neutralization treatment was performed using a weak alkaline aqueous solution.
If so, relatively much water will be in the solution in the system.
Existing. Therefore, for example, an esterification reaction
The polymerization inhibitor used is slightly soluble or insoluble in water
Only in such a case, the (meth) acrylic acid
To prevent polymerization in the solution inside
From a viewpoint, after adding a water-soluble polymerization inhibitor to the solution in the system,
It is desirable to raise the temperature to the temperature specified above.
is there. Further, as the water-soluble polymerization inhibitor,
Is not limited to, for example, hydroquinone,
Metoquinone, catechol and derivatives thereof (for example,
pt-butylcatechol), hydroquinone monomer
Tyl ether and the like. Above all, hydroquino
And methquinone are preferred. In addition, these water-soluble polymerization
The inhibitor may be used alone or in combination of two or more.
Good. The addition amount of the water-soluble polymerization inhibitor is
Total of alcohol and (meth) acrylic acid as raw materials
0.001 to 1% by mass, preferably 0.1 to 1% by mass of the amount used.
001 to 0.1% by mass. Addition of water-soluble polymerization inhibitor
When the amount is less than 0.001% by mass, the polymerization inhibiting ability
Expression may be insufficient, and the amount of water-soluble polymerization inhibitor added
However, if it exceeds 1% by mass, excessive addition
It is uneconomical because it does not provide the appropriate polymerization inhibition ability,
Absent. Further, the production of the esterified product according to the present invention
The method will be described with reference to FIG. FIG. 1 shows the production of the esterified product according to the present invention.
FIG. 2 is a schematic diagram of a typical apparatus configuration used in the method. FIG. 1 shows that the apparatus configuration of this embodiment is
The esterification reaction is carried out by raising the temperature to a predetermined temperature.
After the neutralization reaction, the temperature is lowered to a predetermined temperature to neutralize
Heat exchange means for raising the temperature to remove the dehydrating solvent
(For example, direct heating method such as internal heater, external jacket
Heat pressurized steam, etc.
A reaction vessel 101 having an outer jacket 102 that can be used on the body
Is provided. At this time, the material inside the reaction tank is particularly restricted.
Any known materials can be used without limitation.
If it is made of SUS, preferably SUS30 in terms of corrosion resistance
4, SUS316 and SUS316L, more preferably
SUS316 and SUS316L. Also
Is glass-lined inside the reaction tank.
It may be inert to materials and products. The anti
The tank 101 is made of stainless steel for alcohol
(For example, SUS316) raw material storage tank 103 and
Raw material storage tank 105 for acid and (meth) acrylic acid raw materials, acid
Catalyst storage tank 107 for catalyst, reaction during esterification reaction
Polymerization inhibitor to prevent polymerization in the system (reaction tank 101)
Polymerization inhibitor storage tank 109, esterification reaction
Solution in the system (reaction tank 101) when the dehydrating solvent is distilled off after completion
Store a water-soluble polymerization inhibitor to prevent polymerization in the
Water-soluble polymerization inhibitor storage tank 110 and esterification reaction
A neutralizing agent (neutralizing agent water) for neutralizing the catalyst after the reaction.
Solution) stored carbon steel (eg, high carbon
Steel) storage tanks 111
5, 117, 119, 120 and 121 are linked. Ma
In addition, (meth) acrylic acid is easy to polymerize, for example,
In the case of tacrylic acid, it is polymerized by long-term storage or heat
Trace polymerization inhibitor (0.1% hydroquinone, etc.)
Is added, and it is easy to polymerize even if it crystallizes.
When storing in the raw material storage tank 105, benzene
In addition to preventing crystallization, as shown in FIG.
Pump 116 to keep the temperature at 30-40 ° C
Circulation path 1 with the outer jacket 150 (heat insulation means)
51 are formed, and (meth) acrylic acid raw material is always 3
It is kept at 0 to 40 ° C and circulated so as not to polymerize.
Raw material storage tank 105 for (meth) acrylic acid, piping 115 and
The inside of the pump 116 and the circulation path 151 are corrosive.
(Meth) acrylic acid to prevent corrosion
Lining with corrosion resistant material such as fat
Things are used. Similarly, catalyst storage tank 107 and
Inside the pipe 117, to prevent corrosion by acid catalyst,
Lining with acid-resistant material such as synthetic resin
Is used. Also, beneath the reaction tank 101
In the part, it is synthesized inside the reaction tank 101 by the esterification reaction.
Esterified product (or cement dispersant, etc.)
The esterified product is further used as a monomer component in the reaction vessel 101.
To collect the polymer obtained by polymerization
3 are connected. Further, the reaction tank 101 contains
Appropriate temperature sensor (not shown) for measuring response temperature
(Some places). The temperature sensor
Is the equipment mechanism necessary to maintain the reaction temperature at the specified temperature.
(For example, the jacket 102 attached to the reaction vessel 101
Control unit (not shown) for controlling temperature, etc.
It is electrically connected. Further, in the apparatus configuration of the present embodiment, the reaction
Generated during esterification reaction in the system (in reaction tank 101)
Distillate containing reaction water is distilled out to prevent the formation of gel
After condensed and liquefied while stopping, the reaction water is separated and removed.
Machine to return the remaining distillate at the specified solvent circulation speed
The reaction product water is combined with a dehydrating solvent.
The azeotropic distillate is condensed by the action of an anti-gelling agent
The reaction product water (aqueous phase) is obtained from the liquefied and condensed liquefied distillate.
Is separated and removed, and the remaining condensate (solvent containing mainly dehydrating solvent)
Phase) is refluxed at the above-mentioned solvent circulation rate and returned to the reaction vessel 101.
A circulatory system is formed. For details,
Counter-current (or co-current) contact type vertical multi-tube type circular tube type
The top of the denser 125 is connected by a pipe 123.
Also, the lower bottom of the condenser 125 and the SUS water separator 127
The upper part is connected by a pipe 129. The water separator 127
Is provided with a partition plate 131, and the partition plate 131
Two partitioned chambers 133 and 134 are formed. This
The distillate condensed and liquefied by the condenser 125 is stored.
The lower part of the chamber 133 on the side of
They are connected by a pipe 137. In addition, the processing tank 135
Is connected to a pipe 139 for wastewater. In addition, water separator 1
The lower part of the other chamber 134 of 27 and the reaction tank 101
Are linked. In addition, this pipe 141 is
Solvent storage to store dehydration solvent azeotroping with the reaction product water
The piping 145 connected to the storage tank 143 is joined (connected)
I have. The pipe 141 before the junction (on the water separator 127 side)
A circulation pump 142 is installed on the path. Also,
On the path of the pipe 141 behind the junction (on the side of the reaction tank 101)
Is provided with a flow meter 144. Then, the flowmeter 144
Calculates the solvent circulation speed by integrating the measured flow rates
Electrical connection with the flow measurement system body (not shown)
Has been continued. Furthermore, the top of the condenser 125
A mist nozzle 126 is provided.
Gelation with storage of anti-gelling agent for preventing gelation of distillate
It is connected to the inhibitor storage tank 147 by a pipe 149. In the present invention, the capacitor is S
SU such as US304, SUS316 and SUS316L
Known materials such as S and carbon steel (CS) can be used,
Preferably, the inner surface is reduced to further reduce gel formation.
Use mirror-finished or glass-lined capacitors
Although it can be used, consider the cost of processing and maintenance.
Considering, SUS304, SUS316 and SUS31
6L, preferably SUS316 and SUS316L etc.
SUS capacitors can be preferably used.
Effectively prevents gel formation even when using a capacitor
it can. In addition, the preferably used
The heat transfer area of the densa varies depending on the volume of the reaction tank, etc.
However, for example, the reaction tank 30m ^Three Then 50-500m ^Two , Good
Preferably 100-200m ^Two It is. In the present invention,
Water or oil can be used as a cooling medium for the condenser.
And the like. In addition, the above-mentioned circulating mechanism
Configuration), that is, in the reaction system (in the reaction tank 101),
Distillate containing water produced during the reaction
Then, after condensing and liquefying the gel-like material while preventing its generation,
The reaction product water is separated and removed, and the remaining distillate is refluxed.
Of the mechanism (for the device configuration) after the esterification reaction
The esterified product, which is a product in the system (in the reaction vessel 101)
The distillate containing the dehydrated solvent is distilled from the solution containing
After condensed and liquefied while preventing the formation of
Mechanism for removing distillate containing solvent out of the system
The dehydration solvent is used together with water.
The water-soluble polymerization inhibitor is allowed to act on the distillate
The condensed and liquefied distillate is separated into an aqueous phase and a solvent phase.
And remove them separately by an appropriate method
(Extraction path) is formed. See above for details
The new circulation mechanism (device configuration) has a new condenser 125
Spray nozzle 126 provided at the top of
Prohibition of water-soluble polymerization used to prevent gelation of contained distillate
Aqueous solution (hereinafter simply referred to as a water-soluble gelling inhibitor)
Water-soluble anti-gelling agent storage tank 159
Are connected by a pipe 161. In addition, a water separator 127
Solvent is removed by suction under reduced pressure through pipe 157
Vacuum pump (ejector) 155 is installed
ing. In the method for producing an esterified product according to the present invention,
Is an apparatus for producing an esterified product having the above-described apparatus configuration.
This is performed as follows. First, each raw material storage tank is placed inside the reaction tank 101.
103, 105, catalyst storage tank 107, polymerization inhibitor storage tank
109, piping 113, 115, 11 from the dehydrated solvent storage tank 143
7 and 119 and raw material through pipe 141 through pipe 145.
Alcohol and (meth) acrylic acid, acid catalyst, polymerization inhibition
The specified amount of the agent and the dehydrating solvent as specified above, respectively
Feeding (preparation), esterification conditions specified above
(Reaction temperature, jacket temperature, pressure)
I do. Reaction water generated successively by esterification
Is azeotropic with the dehydrated solvent charged in the reaction vessel 101, and the pipe 1
Distilled through 23. With the gas fluid distilled
Some solvent-water azeotropes pass through condenser 125 and condensate
Be converted to Low boiling point contained in the azeotrope during condensation and liquefaction
In order to prevent the raw material from gelling, store the anti-gelling agent.
The head of the condenser 125 through the piping 149 from the storage tank 147
The amount specified above from the spray nozzle 126 provided at the top
A gelling inhibitor is continuously dropped to form an azeotrope (gas fluid
And both condensed and liquefied products).
Condensed and liquefied azeotrope (including dripped anti-gelling agent)
) Is water from the lower part of the condenser 125 through a pipe 129.
It is stored in the chamber 133 of the separator 127, and separated into two layers of an aqueous phase and a solvent phase.
Separated. Of this, the reaction product water in the lower layer is
Pulled out from the bottom through pipe 137,
It is stored in the processing tank 135. And inside the processing tank 135
Satisfy environmental standards (wastewater standards) as required
Plumbing 139 after being treated chemically or biologically
Through the system. On the other hand, the upper layer
Agent phase (including dripping anti-gelling agent and low boiling material)
) Overflows the partition 131 and stores it in the adjacent room 134
Can be Then, the solvent phase is pumped from the lower part of the chamber 134.
Solvent circulation rate specified above through pipe 141
The temperature is returned to the reaction tank 101 at a time. In the present invention, a gelling inhibitor is provided.
Gel is formed at the site where the anti-gelling agent storage tank is supplied.
Although the site that is likely to be performed is preferable, it is not particularly limited,
For example, the embodiment in FIG. 1, that is, spraying an anti-gelling agent
Spray nozzle 126 installed at the top of the condenser 125
In addition to the piping 12 between the reaction vessel 101 and the condenser 125.
(3) Spray for spraying anti-gelling agent on at least one place on
A mode in which a nozzle is provided, and the like are given. In the latter aspect
Spray nozzle that sprays an anti-gelling agent on the pipe 123
For example, the condensation inside the condenser
(Especially near the top of the tower), start up of the reaction tank and vapor
The joint (flange) between the beam line and the vaporizer
Of the flange between the inlet and the top of the condenser tower
Thermometers and viewing windows installed in the
There are sites where gels are likely to be formed, such as
Of these, the condenser inside the condenser (especially
Near the top of the tower), the reactor and vapor rise line
Between the flange or vapor line and the condenser tower top
Is preferable. End of esterification reaction (esterification rate is specified
After that, the temperature is lowered and the temperature is lowered.
The internal temperature (liquid temperature) is below the specified temperature (90 ° C)
Pass the refrigerant through the outer jacket 102 of the reaction vessel 101 until
Temperature, and then maintain the temperature at or below the specified level.
While adjusting as necessary, pass the pipe 121 from the neutralizer storage tank 111
In the reaction tank 101, the concentration specified above is
Add an aqueous alkali solution (neutralizing agent) diluted to a degree
Partially neutralizes acid catalyst (and part of (meth) acrylic acid)
You. After partial neutralization, the water-soluble polymerization inhibitor was
Inhibitor tank 110 through reaction tube 101 through piping 120
Add to the solution and mix. At normal pressure, the external
Specified above through heat medium (pressurized steam) to the ket 102
The temperature in the reaction vessel 101 is increased by raising the temperature to
Solvent and a large amount of water added during partial neutralization
Other unreacted low-boiling materials (for example, (meth) acrylic
Acid) is also azeotropically distilled out through the pipe 123. Distilling
The solvent-water azeotrope that has been
The liquid is condensed and liquefied through the filter 125. In this case also unreacted
Gel with low boiling point raw materials (for example, (meth) acrylic acid)
Although debris is generated, the dehydrating solvent is removed here
So that only water and low-boiling materials gradually evaporate
Therefore, it is desirable to act a water-soluble polymerization inhibitor.
No. Unreacted low boiling contained in the distillate at the time of this condensation and liquefaction.
In order to prevent the raw material from gelling,
The condenser from the inhibitor storage tank 159 through piping 161
The above is specified from the spray nozzle 126 provided at the top of 125.
Amount of water-soluble gelling agent continuously
Co-current with material (both gas fluid and condensed liquid)
Make contact. Condensed and liquefied distillate (dropped water-soluble
(Including a polymerization inhibitor) is provided from the bottom of the condenser 125.
It is stored in the chamber 133 of the water separator 127 through the pipe 129, and the aqueous phase
(Including dripped water-soluble polymerization inhibitors and low-boiling raw materials
And a solvent phase. Of these,
If the water is to be removed without circulation,
Drained through the drainage pipe 137 and stored in the water treatment tank 135.
Can be Then, in the processing tank 135, if necessary
Chemicals to meet environmental standards (wastewater standards)
After being treated biologically, the body
Wastewater outside the system
In this case, a pipe connected to the reaction tank 101 from the lower part of the chamber 133
(Not shown) and reflux through this pipe
No. ). On the other hand, the solvent phase in the upper layer is charged without reflux.
Since it is necessary to remove it outside the installation, it is attached to the water separator 127.
Using a vacuum pump (ejector) 155
Will be issued. These are either disposed of or
Chemical treatment may be performed using a device outside the system, and the material may be reused. Finally, the dehydrating solvent was distilled off from the solution in the system.
After that, it is connected to the inside of the reaction tank 101 by a pipe (not shown).
Water storage tank (not shown) or water pipe (shown
Water) of the desired esterified product
Obtain a liquid. The obtained aqueous solution of the esterified product is supplied to the pipe 153
It is recovered (stored). In addition, the obtained esterified compound
When using this for the synthesis of cement dispersants, etc.
In the reaction vessel 101 as one of the monomer components.
Performs polymerization and can be a major component of cement dispersants
A polymer may be synthesized. In this case,
The remaining unreacted (meth) acrylic acid added in excess
As it is without separation / removal as the other monomer component
It is preferred to use. The above is the method for producing the esterified product of the present invention.
One embodiment of the present invention has been described with reference to FIG.
The method for producing an esterified product according to the present invention relates to the embodiment.
It is not limited, and after the completion of the esterification reaction, dehydration is performed.
When distilling off the solvent, the distillate containing the dehydrated solvent
If the polymerization inhibitor can be acted on,
There are no restrictions on the manufacturing method (means), device configuration, etc.
It is not a matter of course.
Can be used in combination. According to a second concept, the present invention provides
In the presence of, the following formula: (However, R ¹ Is a char having 1 to 30 carbon atoms
Represents a hydrogen group, R ^Two O is an ox having 2 to 18 carbon atoms
Represents a silalkylene group, wherein each R ^Two Repeat O
The units may be the same or different,
And R ^Two When O is in the form of a mixture of two or more,
R ^Two O repeating units may be added in blocks.
Or n may be added randomly, and n is
Represents the average number of moles of oxyalkylene group added, 1-3
An alkoxypolyalkylene represented by the following formula:
Glycol (herein simply referred to as “alkoxypolyal
"Kylene glycol") with (meth) acrylic acid
Esterification reaction and removal after completion of the esterification reaction
During the water solvent distillation step, the distillate containing the dehydrated solvent
By acting an anti-gelling agent,
Alkylene glycol mono (meth) acrylic acid monomer
(A), the alkoxypolyalkylene glycol
No (meth) acrylic acid-based monomer (a) 5 to 98% by mass,
The following formula (2): (However, R ^Three Represents a hydrogen or methyl group
And M ¹ Is hydrogen, monovalent metal, divalent metal, ammonium
(Meta)
95 to 2% by mass of acrylic acid monomer (b), and this
Other monomers (c) copolymerizable with these monomers (0 to 50)
% (Provided that the sum of (a), (b) and (c) is 10
0% by mass).
Polycarboxylic acid copolymer for powder (in the present specification, simply
The method for producing the “copolymer” or “polymer”)
To provide. In the above concept, the alkoxy polyalkyl
The lenglycol is the first compound described above except that n does not contain 0.
Defined in the same way as alcohol in the concept. Also,
(Meth) acrylic acid and esterification reaction
Similar terms are used for terms used in the concepts
Meaningful. Incidentally, the esterification reaction according to the second concept described above.
In response, an alkoxypolyalkylene glycol and
The amount of (meth) acrylic acid used is
The amount of lenglycol used is defined as p parts by mass and
When the used amount of the lylic acid is q parts by mass, the following formula: 40 ≦ [(p / n ^1/2 ) / Q] × 100 ≦ 200. This
And (meth) acrylic acid to alkoxypolyalkylene
The esterification reaction was carried out in excess of
And the obtained alkoxy polyalkylene glycol
Mono (meth) acrylic acid monomer is (meth) acrylic acid
Is isolated in the form of a mixture containing
As is or without necessity (meth) acrylic acid
(Salt) monomers and monomers copolymerizable with these monomers
In addition, copolymerization is preferably performed without isolation of the mixture.
By subjecting to the reaction, the polycarboxylic acid copolymer is
Manufacturable and preferred. That is, the alkoxypolyalk
Above amounts of lenglycol and (meth) acrylic acid
Adjustment within the range described above,
Isolation of alkylene glycol mono (meth) acrylic acid
Suitable for mass production.
And is preferable from an industrial viewpoint. In the above preferred embodiment, the alkoxy
P parts by mass, which is the amount of
Q) The q parts by mass, which is the amount of acrylic acid, is represented by the following formula: 40 ≦ [(p / n ^1/2 ) / Q] × 100 ≦ 200 (where n is the average number of added moles of the oxyalkylene group)
Which is a number from 1 to 300)
Is required. As used herein, the formula: [(p / n
^1/2 ) / Q] × 100 is also referred to as “K value”, and the K value
Is polyalkylene glycol per mass of carboxylic acid
It is a measure of the average number of chains. In the present invention, K
The value is preferably 42 to 190 (42 ≦ K value ≦ 19
0), more preferably 45 to 160 (45 ≦ K value ≦ 16
0), where the K value is less than 40,
Cement dispersing ability of cement dispersant is not sufficient. Reverse
When the K value exceeds 200, the obtained cement dispersant
The cement dispersing performance of the
Response time is significantly increased and productivity is greatly reduced.
Not good. The polycarboxylic acid based on the second concept
A method for producing a copolymer (including a salt thereof; hereinafter the same) is as follows.
Alkoxy polyalkylene glycol mono (meth) ac
A polymerization reaction is carried out using a lylic acid monomer as a monomer component.
With the above, the polymer of the present invention according to the intended use is obtained.
Is not particularly limited as long as it can
Include those polymerized according to the intended use
Should be understood. For example, Japanese Patent Publication No. 59-1833
No. 8, JP-A-9-86990 and JP-A-9-2
As well as known methods such as the method described in
And (meth) acrylic acid (salt), and if necessary
Polymerization reaction with monomers copolymerizable with these monomers
The cement provides excellent cement dispersibility
But can be, but are not limited to,
Rather than in the detailed description of the polymer of the present invention
That the polymerization methods described in the respective publications can be applied
Needless to say, in addition to these, various conventionally known polymerizations
It goes without saying that the method can be applied. Also, the above
In addition to the method, calcium carbonate, carbon black, ink
Pigment dispersant, scale inhibitor, gypsum / water slurry
Can be used as a dispersant for CWM, a dispersant for CWM, a thickener, etc.
is there. More specifically, for example, the polycarbonate of the present invention
In the method for producing a rubonic acid-based copolymer, an alkoxypolyether is used.
Luylene glycol mono (meth) acrylic acid monomer
With (meth) acrylic acid (salt) monomer and if necessary
Polymerization reaction with monomers copolymerizable with these monomers
I do. Here, the desired polycarboxylic acid copolymer
Can be obtained by using an alkoxy polyalkyl
Lenglycol mono (meth) acrylic acid monomer component, etc.
May be copolymerized. Copolymerization involves polymerization in a solvent or lumps.
It can be performed by a method such as shape polymerization. Polymerization in a solvent may be performed batchwise or continuously.
Can be carried out, and as a solvent used at that time,
Water; methyl alcohol, ethyl alcohol, isopropyl
Alcohols and other lower alcohols; benzene, tolue
Fragrance such as xylene, xylene, cyclohexane, n-hexane
Aliphatic or aliphatic hydrocarbons; esterification of ethyl acetate, etc.
Compounds: ketone compounds such as acetone and methyl ethyl ketone
Object; and the like. Monomer component of esterified material of raw material
And the solubility of the obtained copolymer and the copolymer
From the stool during use, remove water and lower
Using at least one selected from the group consisting of
Preferably. In that case, lower one having 1 to 4 carbon atoms
Among alcohols, methyl alcohol and ethyl alcohol
And isopropyl alcohol are particularly effective. When performing polymerization in an aqueous medium, a polymerization initiator
As ammonium or alkali metal persulfate
Alternatively, a water-soluble polymerization initiator such as hydrogen peroxide is used.
At this time, an accelerator such as sodium bisulfite and Mohr salt is used.
They can be used together. Also, lower alcohol, aromatic
Hydrocarbons, aliphatic hydrocarbons, ester compounds or ketones
Benzoyl peroxy is used for polymerization using ton compounds as solvents.
Peroxides such as sid and lauroyl peroxide;
Hydroperoxides such as hydroperoxides;
When aromatic azo compounds such as zobisisobutyronitrile
Used as a coalescence initiator. At this time, the promotion of amine compounds
An enhancer can be used in combination. In addition, water-lower alcohol
In the case of using a mixed solvent, the above various polymerization initiation
From combinations of initiators or polymerization initiators and accelerators
It can be appropriately selected and used. The polymerization temperature is used
Although it is appropriately determined depending on the solvent and the polymerization initiator, it is usually 0 to 1
It is performed within the range of 20 ° C. In bulk polymerization, benzoyl is used as a polymerization initiator.
Peroxy such as peroxide and lauroyl peroxide
Hydroperoxy such as cumene hydroperoxide
Sid; aliphatic azo compound such as azobisisobutyronitrile
It is carried out within a temperature range of 50 to 200 ° C.
You. In order to control the molecular weight of the obtained polymer,
In addition, a thiol chain transfer agent can be used in combination. This
The thiol-based chain transfer agent used in the case of
-R ^Five -E _g (However, R in the formula ^Five Is a group having 1 to 2 carbon atoms.
Represents an alkyl group, E represents -OH, -COOM ^Two , -CO
OR ⁶ Or -SO _Three M ^Two Represents a group, M ^Two Is hydrogen, monovalent
Group, divalent metal, ammonium group or organic amine group
I, R ⁶ Represents an alkyl group having 1 to 10 carbon atoms.
And g represents an integer of 1 to 2. ),
For example, mercaptoethanol, thioglycerol, thiog
Relic acid, 2-mercaptopropionic acid, 3-merca
Putpropionic acid, thiomalic acid, thioglycolic acid
And octyl 3-mercaptopropionate.
And one or more of these can be used.
You. The polymer thus obtained was used as it was.
Even used as a main component of various applications such as cement dispersants
However, if necessary, further neutralize with an alkaline substance
The resulting polymer salt is used for various applications such as cement dispersants.
It may be used as a main component. Such alkaline substances
As hydroxides and chlorides of monovalent and divalent metals
And inorganic substances such as carbon salts; ammonia; organic amines and the like.
Preferred are mentioned. In the process for producing a polymer of the present invention,
Alkoxypolyalkylene glycol
Mono (meth) acrylic acid monomer component used alone
Or two or more of them may be used in combination. Special
If two or more types are used in combination,
Applicable characteristics (function, performance, etc.) can be expressed
As described above, different types of expression
And the following two combinations are advantageous.
is there. That is, the alkoxypolyalkylene glycol
In the coal mono (meth) acrylic acid monomer, the formula
The average number of added moles n in (1) is from 1 to 97, preferably
Is an integer of 1 to 10 of the first esterified compound (a ¹ )
And the average number of added moles n in the formula (1) is 4 to 100;
Second esterification, preferably an integer from 11 to 100
Object (a ^Two ) (But the second esterified compound)
(A ^Two ) Is the first esterified compound
(A ¹ 3) greater than the average number of moles added
Is advantageous. The first esterified product (a) ¹ )When
Second esterified compound (a ^Two Method for producing a mixture with
Is as described in the method for producing the esterified product.
And the first and second esterified compounds (a ¹ )
And (a ^Two ) Can be prepared separately by esterification
OK, or a mixture of the corresponding alcohols
Ta) It may be produced by an esterification reaction with acrylic acid.
In particular, the latter method provides an industrially inexpensive manufacturing method.
Wear. In this case, the first esterified compound (a ¹ )When
Second esterified compound (a ^Two ) Is 5: 95-9.
The ratio is 5: 5, preferably 10:90 to 90:10. The first esterified product (a ¹ ) As an example
For example, methoxy (poly) ethylene glycol mono (me
TA) acrylate, methoxy (poly) propylene glyco
Mono (meth) acrylate, methoxy (poly) buty
Len glycol mono (meth) acrylate, methoxy
(Poly) ethylene glycol (poly) propylene glycol
Mono (meth) acrylate, methoxy (poly) ethyl
Lenglycol (poly) butylene glycol mono (me
TA) acrylate, methoxy (poly) propylene glyco
(Poly) butylene glycol mono (meth) acryle
Methoxy (poly) ethylene glycol (poly) p
Propylene glycol (poly) butylene glycol mono
(Meth) acrylate, ethoxy (poly) ethylene glycol
Coal mono (meth) acrylate, ethoxy (poly) p
Propylene glycol mono (meth) acrylate, ethoxy
Si (poly) butylene glycol mono (meth) aclayer
G, ethoxy (poly) ethylene glycol (poly) pro
Pyrene glycol mono (meth) acrylate, ethoxy
(Poly) ethylene glycol (poly) butylene glycol
Lumono (meth) acrylate, ethoxy (poly) propyl
Lenglycol (poly) butylene glycol mono (me
TA) acrylate, ethoxy (poly) ethylene glycol
(Poly) propylene glycol (poly) butylene glycol
Examples thereof include coal mono (meth) acrylate. First
Esterified product (a ¹ ) Is the short-chain alcohol in its side chain
It is important to have hydrophobicity. From the viewpoint of easiness of copolymerization, the side chain is
Higher ethylene glycol units are preferred
No. Therefore, (a ¹ ) Means that the average number of moles added is
1 to 97, preferably 1 to 10 (alkoxy) (Po
Re) Ethylene glycol mono (meth) acrylate is preferred
Good. The second esterified compound (a ^Two ) As an example
For example, methoxypolyethylene glycol mono (meth) a
Acrylate, methoxypolyethylene glycol (poly)
Propylene glycol mono (meth) acrylate, meth
Xypolyethylene glycol (poly) butylene glycol
Lumono (meth) acrylate, methoxypolyethylene
Recall (poly) propylene glycol (poly) butyle
Glycol mono (meth) acrylate, ethoxy poly
Ethylene glycol mono (meth) acrylate, ethoxy
Polyethylene glycol (poly) propylene glycol
Lumono (meth) acrylate, ethoxy polyethylene
Recall (poly) butylene glycol mono (meth) ac
Relate, ethoxy polyethylene glycol (poly)
Propylene glycol (poly) butylene glycol mono
(Meth) acrylate and the like are exemplified. To obtain high water reduction, the second
(A ^Two ) Having an average addition mole number of 4 to 100
Disperse cement particles by steric repulsion and hydrophilicity
It is important that For that, polyalkylene
Many oxyethylene groups are introduced into the glycol chain.
Are preferred, and polyethylene glycol chains are most preferred.
No. Therefore, the second esterified compound (a ^Two ) Alkylene
The average number of added moles n of the glycol chain is 4 to 100, preferably
Or 11-100. In the method for producing the polymer of the present invention,
(Meth) acrylic acid (salt) simple substance
Examples of bodies include acrylic acid, methacrylic acid and
Monovalent metal salts, divalent metal salts, ammonium salts and the like of these acids
And organic amine salts.
Alternatively, two or more kinds can be used. In the method for producing a polymer of the present invention,
Esterified monomer and (meth) a
Monomeric copolymerizable with the monomer component of acrylate (salt) monomer
Examples of bodies are maleic acid, fumaric acid, citracone
Dicarboxylic acids such as acid, mesaconic acid and itaconic acid;
Dicarboxylic acids and HO (R ¹¹ O) _r R ¹² (However,
R ¹¹ O is one of oxyalkylene groups having 2 to 4 carbon atoms.
Or a mixture of two or more, and in the case of two or more,
Locked or random
Often, r is the average number of moles of oxyalkylene group added.
Represents an integer from 1 to 100, ¹² Is hydrogen or carbon source
Represents an alkyl group having from 1 to 22, preferably from 1 to 15,
You. Or a monoester with an alcohol represented by
Are diesters; (meth) acrylamide, (meth) a
Unsaturated amides such as krylalkylamide; vinyl acetate
And vinyl esters such as vinyl propionate; vinyl
Sulfonic acid, (meth) allylsulfonic acid, sulfoethyl
(Meth) acrylate, 2-methylpropanesulfonic acid
Unsaturation of (meth) acrylamide, styrenesulfonic acid, etc.
Sulfonic acids and their monovalent metal salts, divalent metals
Salts, aluminium salts, organic amine salts; styrene, α-
Aromatic vinyls such as methylstyrene; having 1 to 1 carbon atoms
8, preferably 1 to 15 aliphatic alcohols or
Phenyl group-containing alcohols such as
TA) Esters with acrylic acid; polyalkylene glycos
Mono (meth) acrylate; polyalkylene glyco
Mono (meth) allyl ether and the like.
One or more of these can be used. The copolymer thus obtained was used as a main component.
In the cement dispersant of the present invention, a good cement content
Dispersion performance and slump holding performance can be exhibited. Further, the cement dispersant of the present invention includes
In addition to the polymer component specified in, the conventionally known naphthalene-based
Cement dispersant, aminosulfonic acid cement dispersant,
Polycarboxylic acid cement dispersant and lignin cement
At least one species selected from the group consisting of
Mention dispersants may be included. That is, the security of the present invention
In the dispersant, the polymer may be used alone.
And, if necessary, to add more value
Various components shown below and below can also be blended.
Therefore, the composition of these
It differs greatly depending on the presence or absence of additional functions.
100% by mass (total amount) or the main component
Therefore, the above-mentioned polymer component was
To the mode of adding an appropriate amount to the cement dispersant of
It cannot be defined uniquely. However, the present invention
Of polycarboxylic acid copolymer in cement dispersants
The compounding amount is usually 5 to 100% by mass with respect to all components,
Preferably it is 50 to 100% by mass. Further, the cement dispersant of the present invention includes
In addition to known cement dispersants, air entrainers, cement wet
Lubricants, swelling agents, waterproofing agents, retarders, quick-setting agents, water-soluble polymers
Substances, thickeners, flocculants, drying shrinkage reducers, strength enhancers,
A curing accelerator, an antifoaming agent and the like can be blended. The polymer thus obtained is used as a main component.
The cement dispersant used should be at least cement and water.
By mixing with the cement composition
Promotes dispersion. [0171] The cement dispersant of the present invention comprises Portland
Cement, Belite-rich cement, Alumina cement
Hydraulic cement, such as mixed cement, mixed cement, or stone
It can be used for hydraulic materials other than cement such as plaster.
Wear. [0172] The cement dispersant of the present invention is as described above.
As it has an effect, compared to the conventional cement dispersant
The effect is excellent even when added in small amounts. For example, hydraulic
Used for mortar and concrete using cement
In the case, 0.001 to 5% of cement mass, preferably
Is added at the time of kneading at a ratio of 0.01 to 1%.
do it. High water reduction rate achieved by this addition, slump
Improved loss prevention performance, reduced unit water volume, increased strength,
Various favorable effects such as improvement of durability
You. If the amount is less than 0.001%, the performance is insufficient.
On the contrary, even if a large amount exceeding 5% is used, the effect is not actually obtained.
The quality leveled off and became disadvantageous in terms of economy. The cement dispersant of the present invention has a specific weight
Has a uniform molecular weight and peaks from the weight average molecular weight
Polymers with a specific value after subtracting the molecular weight are the main components
It is desirable that this is a cement dispersant. this
The weight average of the polycarboxylic acid copolymer according to the present invention
The molecular weight is determined in the optimum range as appropriate for the intended use.
For example, gel permeation chroma
50 in terms of polyethylene glycol by torography
0-500000, especially 5000-300000
It is preferable that Also, the weight average molecular weight of the polymer
From the value obtained by subtracting the peak top molecular weight from 0 to 800
0, preferably 0-7000
is there. If the weight average molecular weight is less than 500, cement dispersion
It is not preferable because the water reducing performance of the agent is reduced. 5
If the molecular weight exceeds 00000, water reduction of cement dispersant
Performance and slump loss prevention
No. Also, the peak top molecular weight is calculated from the weight average molecular weight.
If the subtracted value exceeds 8000, the obtained
Is preferred due to the reduced slump retention performance of
I don't. EXAMPLES The present invention will be described in more detail with reference to the following examples.
Will be described. In the examples, unless otherwise specified,
“%” Represents “% by mass” and “parts” represents “parts by mass”.
Example 1 A thermometer, a stirrer, a produced water separator and a reflux condenser (con
Glass reactor with an outer jacket equipped with
Methoxypoly (n = 25) ethyl
16500 parts of lenglycol, 4740 parts of methacrylic acid
(K value = 70), p-toluenesulfonic acid hydrate 235
Parts, phenothiazine 5 parts and cyclohexane 1060
And an esterification reaction was carried out at a reaction temperature of 115 ° C.
Was. Separately, from the start of cyclohexane reflux,
Phenothiazine 0.5
500.5 parts of a cyclohexane solution containing 1 part by weight was dropped.
Confirmed that the esterification rate reached 100% in about 20 hours
did. 49% to 22255 parts of the obtained esterification reaction solution
Add 135 parts of aqueous sodium hydroxide solution and 4890 parts of water
To neutralize paratoluenesulfonic acid and hydroquinone 8
The mixture was heated to 105 ° C, and cyclohexane was
And distilled off azeotropically. During the distillation of cyclohexane,
To the top of the sensor, add 301 parts of water containing 1 part of hydroquinone
It was dropped. Then, after the cyclohexane is distilled off, the adjusted water is added.
This gave an 80% aqueous solution of an esterified product (1). Less than
After repeating the above operation for several batches,
When the inside of the reflux condenser was inspected, no gel was found.
Was. The reaction composition in the esterification step of this example,
Reaction conditions and esterification rates, neutralization conditions in the neutralization step,
Is a condenser in the distillation process of cyclohexane and cyclohexane
The composition of the dripping into the flow cooling pipe and the operation of
Table 1 below shows the state of the capacitor after repetition.
You. Example 2 In Example 1, a thermometer, a stirrer, a produced water separator and
And multi-tube condenser [Body (shell): 750 mm inside diameter]
× 4000 mm length, heat transfer tube (tube): 24 m inside diameter
mx 485, heat transfer area: 150m ^Two External jig with
SUS316 reaction tank with racket (Contents: 30m ^Three )
8 was used in the same manner as in Example 1 except that
0% aqueous esterified product was obtained, and the obtained esterified product was obtained.
After the reaction of the aqueous solution, check the inside of the condenser
As a result, no gel was found. Example 3 In Example 1, a thermometer, a stirrer, a produced water separator and
And multi-tube condenser [Body (shell): 750 mm inside diameter]
× 4000 mm length, heat transfer tube (tube): 24 m inside diameter
mx 485, heat transfer area: 150m ^Two External jig with
Glass-lined reaction tank with racket (contents: 30
m ^Three ) As in Example 1 except that
To give an 80% aqueous solution of the esterified product.
After the reaction is completed,
As a result, no gel was found. Comparative Example 1 A thermometer, a stirrer, a produced water separator and a reflux condenser (con
Glass reactor with an outer jacket equipped with
Methoxypoly (n = 25) ethyl
16500 parts of lenglycol, 4740 methacrylic acid
Parts, paratoluenesulfonic acid hydrate 235 parts, phenothi
Charge 5 parts of azine and 1060 parts of cyclohexane,
The esterification reaction was performed at a reaction temperature of 115 ° C. Separately,
From the start of reflux of the chlorohexane to the end of the esterification reaction,
The top of the condenser contains 0.5 parts of phenothiazine
500.5 parts of a hexane solution was added dropwise. In about 20 hours
It was confirmed that the esterification rate had reached 100%. Next
Then, in 22255 parts of the obtained esterification reaction solution, 49% water was added.
Add 135 parts of sodium oxide solution and 4890 parts of water
Neutralize paratoluenesulfonic acid, hydroquinone 8 parts
And raise the temperature to 105 ° C.
Was removed by azeotropic distillation. During the distillation of cyclohexane,
Hydroquinone aqueous solution was not dropped on the top of the plant
Was. After distilling off cyclohexane, adjust water was added to make 8
An aqueous solution of 0% esterified product was obtained. Perform the above operations
After the switch is repeated, the inside of the reflux condenser which is the condenser
Upon inspection, a large amount of gel was observed. The reaction composition in the esterification step of this comparative example,
Reaction conditions and esterification rates, neutralization conditions in the neutralization step,
Is a condenser in the distillation process of cyclohexane and cyclohexane
The composition of the dripping into the flow cooling pipe and the operation of
Table 1 below shows the state of the capacitor after repetition.
You. [Table 1] Example 4 Thermometer, stirrer, produced water separator and multi-tube condenser
[Body (shell): 750 mm inside diameter x 4000 m length
m, heat transfer tube (tube): inner diameter 24 mm x 485, transfer
Thermal area: 150m ^Two Glass with external jacket
Lining reaction tank (Contents: 30m ^Three )
Li (n = 25) 16500 parts of ethylene glycol, meta
4740 parts of crylic acid, paratoluenesulfonic acid monohydrate
235 parts, phenothiazine 5 parts and cyclohexane 1
060 parts were charged, and the esterification reaction was performed at a reaction temperature of 115 ° C.
Was done. Separately from the start of cyclohexane reflux,
Cyclohexanyl containing phenothiazine
Solution (A) (concentration of phenothiazine in cyclohexane)
The degree was set to 1000 mass ppm. ) To 0.35 parts / mi
Condensed residue circulated from the water separator to the reactor at a speed of n
20 parts / min of part (B) of (mainly cyclohexane)
After mixing (A) and (B) at the speed of
Down to the top of the condenser through the
did. In about 20 hours, the esterification rate reaches 100%
I confirmed that. And 49% aqueous sodium hydroxide
Add 135 parts of liquid and 4890 parts of water and add paratoluene sulfo.
Acid, neutralized with 8 parts of hydroquinone and heated.
Chlohexane was distilled off azeotropically with water. Cyclohexane
During the distillation, 1 part of hydroquinone was added to the top of the condenser.
301 parts of water were dropped. Adjust after cyclohexane distillation
Water was added to obtain an 80% aqueous esterification solution. More than
After repeating the operation for 3 batches, visually check the inside of the capacitor.
Upon inspection, no gel was generated. Another year
While the above batch operation is continued, look inside the capacitor.
Visual inspection revealed that only a very small amount of gel was generated.
Not recognized. This is the same as that of Example 7 below for one year
Are very small when compared with each other.
It was reduced to 1/10 or less visually. The reaction composition, reaction conditions and condensation
Composition of anti-gelling agent solution to be dropped to the top of sa, partial neutralization strip
The conditions, solvent distillation conditions and experimental results are shown in Tables 2 to 4 below.
You. Example 5 In Example 4, a thermometer, a stirrer, a produced water separator and
And multi-tube condenser [Body (shell): 750 mm inside diameter]
× 4000 mm length, heat transfer tube (tube): 24 m inside diameter
mx 485, heat transfer area: 150m ^Two External jig with
SUS316 reaction tank with racket (Contents: 30m ^Three )
Was used in the same manner as in Example 4 except that
When the inside of the capacitor was visually inspected,
There was no. The batch operation was continued for another year.
Later, when the inside of the capacitor was visually inspected,
Only the formation of a gel-like substance was confirmed. Example 6 In Example 4, a thermometer, a stirrer, a produced water separator and
With external jacket with cooling and reflux condenser (condenser)
A glass reaction tank (contents: 30 liters) is used as the reaction tank.
Inside the capacitor in the same manner as in Example 4 except that
Was visually inspected, and no gel was found.
After continuing the above batch operation for another year,
Visual inspection of the inside of the reflux cooling pipe
Only a very small amount of gel was generated. Example 7 Thermometer, stirrer, product water separator and multi-tube condenser
[Body (shell): 750 mm inside diameter x 4000 m length
m, heat transfer tube (tube): inner diameter 24 mm x 485, transfer
Thermal area: 150m ^Two Glass with external jacket
Lining reaction tank (Contents: 30m ^Three )
Li (n = 25) 16500 parts of ethylene glycol, meta
4740 parts of crylic acid, paratoluenesulfonic acid monohydrate
235 parts, phenothiazine 5 parts and cyclohexane 1
060 parts were charged, and the esterification reaction was performed at a reaction temperature of 115 ° C.
Was done. Separately from the start of cyclohexane reflux,
Cyclohexanyl containing phenothiazine
Solution (A) (concentration of phenothiazine in cyclohexane)
The degree was set to 1000 mass ppm. ) To 0.35 parts / mi
Condensed residue circulated from the water separator to the reactor at a speed of n
20 parts / min of part (B) of (mainly cyclohexane)
After mixing (A) and (B) at the speed of
Down to the top of the condenser through the
did. In about 20 hours, the esterification rate reaches 100%
I confirmed that. And 49% aqueous sodium hydroxide
Add 135 parts of liquid and 4890 parts of water and add paratoluene sulfo.
Acid, neutralized with 8 parts of hydroquinone and heated.
Chlohexane was distilled off azeotropically with water. Cyclohexane
During the distillation, 1 part of hydroquinone was added to the top of the condenser.
301 parts of water were dropped. Adjust after cyclohexane distillation
Water was added to obtain an 80% aqueous esterification solution. More than
After repeating the operation for 3 batches, the inside of the condenser was inspected.
However, no gel was generated. For another year,
After continuing the batch operation, visually check the inside of the capacitor.
Inspection revealed that a very small amount of gel was generated.
It has been certified. This is compared with that of Example 4 above in one year.
In this case, a difference of 10 times or more was visually observed. The reaction composition, reaction conditions and condensation
Composition of anti-gelling agent solution to be dropped to the top of sa, partial neutralization strip
The conditions, solvent distillation conditions and experimental results are shown in Tables 2 to 4 below.
You. Example 8 In Example 7, a thermometer, a stirrer, a produced water separator and
And multi-tube condenser [Body (shell): 750 mm inside diameter]
× 4000 mm length, heat transfer tube (tube): 24 m inside diameter
mx 485, heat transfer area: 150m ^Two External jig with
SUS316 reaction tank with racket (Contents: 30m ^Three )
Was used in the same manner as in Example 7 except that
When the inside of the capacitor was visually inspected,
There was no. The batch operation was continued for another year.
Later, when the inside of the capacitor was visually inspected,
It was confirmed that a gel was generated. Example 9 In Example 7, a thermometer, a stirrer, a produced water separator and
With external jacket with cooling and reflux condenser (condenser)
A glass reaction tank (contents: 30 liters) is used as the reaction tank.
Inside the capacitor in the same manner as in Example 7 except that
Was visually inspected, and no gel was found.
After continuing the above batch operation for another year,
Visual inspection of the inside of the reflux cooling pipe
It was confirmed that an amount of gel was generated. Example 10 A thermometer, a stirrer, a water separator and a multi-tube condenser
Part (shell): inner diameter 750mm x length 4000mm, transmission
Heat tube (tube): Inside diameter 24mm x 485, heat transfer surface
Product: 150m ^Two Glass rye with external jacket
Reaction tank (contents: 30m) ^Three ), Methoxy poly
(N = 25) 16500 parts of ethylene glycol,
4740 parts of lylic acid, paratoluenesulfonic acid monohydrate 2
35 parts, phenothiazine 5 parts and cyclohexane 10
60 parts were charged and the esterification reaction was conducted at a reaction temperature of 115 ° C.
went. Separately, ester from the start of reflux of cyclohexane
Cyclohexane containing phenothiazine
Solution (A) (concentration of phenothiazine in cyclohexane
To 1000 ppm by mass. ) Only 0.35 parts / m
At the speed of in the downward nozzle provided in the condenser
To the top of the condenser. In about 20 hours, the esterification rate reaches 100%
I confirmed that. And 49% aqueous sodium hydroxide
Add 135 parts of liquid and 4890 parts of water and add paratoluene sulfo.
Acid, neutralized with 8 parts of hydroquinone and heated.
Chlohexane was distilled off azeotropically with water. Cyclohexane
During the distillation, 1 part of hydroquinone was added to the top of the condenser.
301 parts of water were dropped. Adjust after cyclohexane distillation
Water was added to obtain an 80% aqueous esterification solution. More than
After repeating the operation for 3 batches, the inside of the condenser was inspected.
However, no gel was generated. For another year,
After continuing the batch operation, visually check the inside of the capacitor.
Inspection revealed that gel was generated.
Was. This is a comparison with that of Example 4 above in one year.
In this case, a difference of 1000 times or more was visually observed. The reaction composition, reaction conditions and condensation
Composition of polymerization inhibitor solution dropped to the top of
The conditions, solvent distillation conditions and experimental results are shown in Tables 2 to 4 below.
You. Example 11 A thermometer, a stirrer, a produced water separator and a reflux condenser (con
Glass reactor with an outer jacket equipped with
Methoxy poly (n = 25)
16500 parts of Tylene glycol, 4740 methacrylic acid
Parts, p-toluenesulfonic acid monohydrate 235 parts, pheno
Charge 5 parts of thiazine and 1060 parts of cyclohexane
The esterification reaction was performed at a reaction temperature of 115 ° C. What
Note that the esterification reaction ends from the start of cyclohexane reflux.
Until the gelation prevention measures are taken,
Needless to say, no gelling agent solution was allowed to act. Esterification rate reaches 100% in about 20 hours
I confirmed that. And 49% aqueous sodium hydroxide
Add 135 parts of liquid and 4890 parts of water and add paratoluene sulfo.
Acid, neutralized with 8 parts of hydroquinone and heated.
Chlohexane was distilled off azeotropically with water. Cyclohexane
During the distillation, 1 part of hydroquinone was added to the top of the condenser.
301 parts of water were dropped. Adjust after cyclohexane distillation
Water was added to obtain an 80% aqueous esterification solution. More than
After repeating the operation for 3 batches, the inside of the condenser was inspected.
However, generation of a large amount of gel was observed. Reaction composition, reaction conditions and partial neutralization of this comparative example
The conditions, solvent distillation conditions and experimental results are shown in Tables 2 to 4 below.
You. In this example, the gel-like material can be easily observed.
Periodically observe the inside of the cooling reflux tube, which is a condenser.
It was observed that the formation of gel-like material was at the top of the condenser.
However, the gel-like substance produced here is
The gel-like material is confirmed on the entire capacitor because it flows down partly
did it. [Table 2] [Table 3] [Table 4] Example 12 Thermometer, stirrer, dropping funnel, nitrogen inlet tube, thermometer, stirring
Stirrer, generated water separator and reflux condenser (condenser)
Glass reaction tank with external jacket provided (content: 30
Liters), 8200 parts of water is charged and the above mixture is stirred under stirring.
The reactor was replaced with nitrogen, and the temperature was raised to 80 ° C in a nitrogen atmosphere.
Was. Next, the 80% obtained in Example 1 was placed in the reactor.
3-merca to 13100 parts of an aqueous solution of the esterified product (1)
Take a solution of 94 parts of pppropionic acid in 4 hours
And at the same time, add 125 parts of ammonium persulfate to water.
An aqueous solution dissolved in 1000 parts was dropped over 5 hours.
Was. After completion of the dropwise addition, the reaction mixture is maintained at 80 ° C. for 1 hour.
Was. Further, the pH of the reaction mixture was adjusted to sodium hydroxide.
Gel permeation by adjusting to 8
Polyethylene glycol by application chromatography
Of the present invention having a weight average molecular weight of 21,000 in terms of
Bonic acid (1) was obtained. The polycarboxylic acid thus obtained
Using (1) as a cement dispersant as it is,
Prepare cement composition (1) according to mortar test method
Then, the flow value was measured. The results are shown in Table 5 below. <Mortar test method>
240 containing a cement dispersant [polycarboxylic acid (1)]
Portland cement as part of cement (Pacific
Cement) and 800 parts of Toyoura standard sand
Knead with a rutar mixer to prepare cement composition (1).
Made. The amount of the cement dispersant added is shown in Table 5 below.
You. Next, this cement composition (1) was treated with
After filling into a 5 mm, 55 mm high hollow cylinder, the cylinder is
Vertically gently lifted and spread cement composition (1)
The major axis and the minor axis were measured, and the average was taken as the flow value. Example 13 In Example 1, methoxypoly (n = 25) ethylene
The amount of glycol used was 19430 parts and methacryl
After changing the amount of acid used to 1810 parts (K value = 215)
Outside, the same esterification reaction as in Example 1 was performed.
After about 90 hours, an esterification rate of about 99% was confirmed. Next
After the cyclohexane is distilled off azeotropically with water,
Was added to obtain an aqueous 80% esterified product solution (2). Next, a thermometer, a stirrer, a produced water separator and
With external jacket with cooling and reflux condenser (condenser)
Water 820 in a glass reactor (contents: 30 liters)
0 parts were charged, and the reactor was replaced with nitrogen under stirring.
The temperature was raised to 80 ° C. in an atmosphere. Then, in the reactor
The 80% aqueous solution of the esterified product obtained above (2)
Dissolve 58 parts of 3-mercaptopropionic acid in 13700 parts
The dissolved solution was added dropwise over 4 hours, and
Water solution of 122 parts of ammonium dissolved in 2300 parts of water
The solution was added dropwise over 5 hours. After the addition is completed, the reaction mixture is
Maintained at 80 ° C. for 1 hour. Furthermore, the p of the reaction mixture
To adjust H to 8 with sodium hydroxide
By gel permeation chromatography
Weight average molecular weight of 1970 in terms of polyethylene glycol
0 polycarboxylic acid (2) was obtained. The polycarboxylic acid thus obtained
Example 1 using (2) as a cement dispersant as it was
Cement group according to the mortar test method
Product (2) was prepared and the flow values were measured. The results below
It is shown in Table 5. [Table 5] From the results shown in Table 5, the K value is preferable.
Above the upper limit of the range (40 to 200), the flow value becomes
Markedly lower, thus reducing cement dispersibility.
It has been certified. (1) Method for producing esterified product of the present invention
The method comprises the steps of using an alcohol represented by the above formula (1) in a dehydrated solvent.
Esterification reaction between toluene and (meth) acrylic acid
When the dehydration solvent is distilled off after the completion of the sterilization reaction, the
Activating polymerization inhibitors on distillates containing solvents
Can effectively prevent the formation of gel-like material,
Can prevent blockage of equipment such as capacitors and piping paths.
When circulating a dehydrating solvent in the esterification reaction,
When the equipment used is also used for distilling off the dehydrating solvent
Is the gel-like substance formed when the dehydrating solvent is distilled off.
Repeating the equipment for producing sterilized products (continuously, so to speak)
In the case of operation, esterification reaction in the next batch
The distillate from which the water of reaction was separated and removed
When refluxing, there is a danger that the gel-like substance is brought into the reaction system.
There is no ruggedness, so the quality and performance of
I will not invite you. Therefore, production using the esterified product
Performance and quality of products such as cement dispersants
It does not drop due to objects. (2) In the present invention, the above (1)
The method for producing an esterified product according to the above, further comprising:
In the region where the distillate containing the dehydrating solvent is condensed.
The anti-gelling agent contained in the distillate contains
Excellent for gel-forming materials such as low-boiling materials
Can be used effectively and effectively.
The function and effect shown in (1) can be obtained very remarkably.
You. (3) Further, in the present invention, the above (1)
In the method for producing an esterified product according to
Gelling by applying the agent in the condenser
Inhibitors such as unreacted low boiling raw materials contained in the distillate
It is extremely effective and effective for raw materials
The effect shown in (2) above
The same operation and effect as those described above can be obtained. (4) Further, in the present invention,
(1) In the method for producing an esterified product according to (3),
The azeotropic distillation of the dehydrated solvent with water
To mix the anti-gelling agent with water
To achieve the effects described in (1) to (3) above.
As well as the removal and removal of dehydrated solvent
And is distilled (evaporated) azeotropically with water from the solution in the system.
Distillate composition, most of which is water,
Unreacted low boiling source dissolved in water which makes up the majority of distillate
It is very advantageous for acting on the material quickly. (5) Further, according to the present invention,
In the method for producing an esterified product according to (4),
If the anti-gelling agent is water-soluble,
Since the inhibitor can be dissolved in water and acted on,
The effects described in the above (1) to (4) can be obtained.
And easy to handle; distillate is condensate
Quickly by using contact methods such as parallel flow contact
And, for example, prevent gelation
Gaseous distillate into an aqueous solution of the agent dissolved in a solvent
If this is done, contact the anti-gelling agent simultaneously with liquefaction.
Various methods to make it work very efficiently
There is an advantage that it can be adopted.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic view of a typical apparatus configuration used in a method for producing an esterified product according to the present invention. FIG. 2 is a schematic explanatory view showing an embodiment of a manufacturing apparatus of the present invention including a device configuration of a typical anti-gelling agent supply mechanism according to a second embodiment of the present invention. FIG. 3 is a schematic explanatory view showing a state where a nozzle is installed in an overhead line immediately before a condenser. FIG. 4 is a schematic explanatory view of a water separator having a storage unit. [Description of Signs] 101: reaction tank, 102, 150 ... jacket, 103 ... raw material storage tank for alcohol, 105 ... raw material storage tank for (meth) acrylic acid, 107 ... catalyst storage tank, 109 ... storage of polymerization inhibitor Tank, 111 ... Neutralizer storage tank, 113, 115, 117, 119, 121, 123, 129, 137, 139, 141, 145, 149, 15
3,157… Piping, 116… Pump, 125… Condenser, 126… Spray nozzle, 127… Water separator, 131… Partition plate, 133, 134… Chamber inside water separator, 135… Treatment tank of reaction generated water, 142 ... circulation pump, 143 ... dehydration solvent storage tank, 147 ... anti-gelling agent storage tank, 151 ... circulation path, 155 ... vacuum pump, 159 ... water-soluble anti-gelling agent storage tank, 501 ... reaction tank, 502 ... jacket 503, 520-525 ... piping, 505 ... condenser, 506 ... nozzle part, 507 ... water separator, 508 ... storage tank, 509 ... polymerization inhibitor solution storage tank, 510-513 ... pump.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C08G 65/332 C08G 65/332 // C04B 103: 40 C04B 103: 40 F-term (Reference) 4J005 AA04 BC00 BD02 4J027 AC02 AC06 BA06 CD00 4J100 AJ02Q AK03Q AK08Q AK13Q AL08P BA04P BA08P CA04 CA05 FA03 JA67

Claims (1)

[Claim 1] In the presence of a dehydrating solvent, the following formula: (However, R ¹ represents a hydrocarbon group having 1 to 30 carbon atoms, R ² O represents an oxyalkylene group having 2 to 18 carbon atoms, and the repeating unit of each R ² O is the same.) And when R ² O is in the form of a mixture of two or more, the repeating units of each R ² O may be added in block form or added in random form. And n represents the average number of moles of the oxyalkylene group added and is a number from 1 to 300), and the esterification reaction of the alkoxypolyalkylene glycol with (meth) acrylic acid is completed. In the subsequent step of distilling off the dehydrated solvent, the anti-gelling agent is acted on the distillate containing the dehydrated solvent to obtain an alkoxypolyalkylene glycol mono (meth) acrylic acid-based monomer. The resulting body (a), said alkoxy polyalkylene glycol mono (meth) acrylic acid monomer (a) 5 to 98 wt%, the following formula (2): ## STR2 ## (Where R ³ represents hydrogen or a methyl group, and M ¹ represents hydrogen, a monovalent metal, a divalent metal, an ammonium group or an organic amine group) (b) a (meth) acrylic acid-based monomer (b) 95 to 2% by mass, and 0 to 50% by mass of another monomer (c) copolymerizable with these monomers (however,
A total of (a), (b) and (c) being 100% by mass).