JPH08231608A - Polymer scale inhibitor and production of polymer by using same - Google Patents

Abstract

PURPOSE: To obtain a polymer scale inhibitor effective in the polymerization of an ethylenically unsaturated monomer by using a reaction product of a condensate of an aminobenzene compound with p-benzoquinone. CONSTITUTION: A condensate is produced by condensing an amino-benzene compound such as aniline, p-phenylenediamine, p-amino-phenol, p-chloroaniline or p-methylaniline in the presence of a catalyst in a solvent This condensate is reacted with p-benzoquinone in a solvent to obtain a reaction product. The obtained reaction product as the principal component is mixed with desirably an inorganic colloid (e.g. colloidal aluminum hydroxide) to obtain a polymer scale inhibitor. When an ethylenically unsaturated monomer (e.g. vinyl chloride) is polymerized, this inhibitor is applied to the inside wall of the polymerizer to form a coating film having an effect of inhibiting the deposition of polymer scales thereon, and the polymerization is performed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polymer scale anti-adhesion agent used for polymerizing a monomer having an ethylenically unsaturated double bond and a method for producing a polymer using the same.

[0002]

2. Description of the Related Art It is known that when a monomer having an ethylenically unsaturated double bond is polymerized, a polymer scale tends to adhere to the inner wall surface of a polymerization vessel. If the polymer scale adheres, the yield of the polymer, the cooling capacity of the polymerization vessel, etc. will decrease, and as a result of the polymer scale peeling and mixing into the polymer, the molding obtained by molding such a polymer The disadvantage is that the quality of the product is reduced. Also,
The work of removing the adhered polymer scale requires not only an excessive amount of labor and time, but also unreacted monomers present in the polymer scale may cause damage to the human body.

Conventionally, for example, in a method of suspension polymerization of a vinyl halide monomer, in order to prevent the polymer scale from adhering to the inner wall surface of the polymerization vessel, the polymer scale is attached to the inner wall surface of the polymerization vessel. A method of forming a coating film comprising an inhibitor is known. Examples of the polymer scale adhesion preventive agent used in this method include a specific polar compound (Japanese Patent Publication No. 45-30343), a dye or a pigment (Japanese Patent Publication No. 45-308).
35, 52-24953), aromatic amine compounds (JP-A-51)
-50887), a reaction product of a phenol compound and an aromatic aldehyde (JP-A-55-54317), and the like. However, a coating film made of these polymer scale anti-adhesion agents has a drawback that it is easily dissolved in a monomer such as styrene, α-methylstyrene, acrylic acid ester, acrylonitrile or vinyl acetate. Therefore, when polymerizing a monomer mixture containing these monomers, the polymer scale is effectively prevented from adhering to the inner wall surface of the polymerization vessel or the like even if the above-mentioned polymer scale adhesion preventing agent is used. Can not do it. In particular, when the concentration of the above-mentioned monomer is high, or when the concentration is low and the polymerization time is long, the polymer scale tends to adhere.

[0004]

The object of the present invention, even when polymerizing a monomer mixture having an ethylenically unsaturated double bond mainly composed of the above-mentioned monomers such as styrene, An object of the present invention is to provide a polymer scale adhesion preventive agent capable of sufficiently preventing adhesion of polymer scale to the inner wall surface of a polymerization vessel and the like, and a method for producing a polymer using the same.

[0005]

The first aspect of the present invention is directed to the polymerization of a monomer having an ethylenically unsaturated double bond containing a reaction product of a condensate of an aminobenzene compound and p-benzoquinone. It is a polymer scale adhesion preventive agent.

The second aspect of the present invention is a polymerization process comprising the step of polymerizing a monomer having an ethylenically unsaturated double bond in a polymerization vessel having a coating film having a polymer scale adhesion preventing property on the inner wall of the polymerization vessel. In the method for producing a polymer, there is provided the method for producing a polymer, wherein the coating film having the polymer scale adhesion preventing property comprises the polymer scale adhesion preventing agent. Hereinafter, the present invention will be described in detail.

(Polymer scale anti-adhesion agent) The polymer scale anti-adhesion agent of the present invention contains a reaction product of the aminobenzene compound condensate and p-benzoquinone. Examples of the condensate of the aminobenzene compound used in the reaction product include those represented by the following formula:

[0008]

Embedded image [In the formula, R ¹ and R ² are independently —H, —NH ₂ , —Cl, —
OH, condensates of aminobenzene compound represented by represents a -NO ₂ or -CH _3] and the like.

Specific examples of the aminobenzene compound represented by the above general formula include aniline, o-, m- or p-phenylenediamine, o-, m- or p-aminophenol, o-, m- or p-chloroaniline, o
-, M- or p-methylaniline, o-, m- or p-
Nitroaniline, 2,4-diaminotoluene, 2,4-
Diaminophenol, 1,2-diamino-4-nitrobenzene, 2,5-dichloroaniline, 1,2,4-triaminobenzene compound, 4-chloro-ortho-phenylenediamine, 2-amino-4-chlorophenol, etc. Can be mentioned. You may use these individually by 1 type or in combination of 2 or more type.

Examples of the method for condensing the aminobenzene compound include a solution condensation method in which the aminobenzene compound is condensed in a solvent in the presence of a catalyst.

Examples of the solvent include polar solvents such as dimethylformamide, N, N-dimethylacetamide, hexamethylphosphoric triamide, N-methylpyrrolidone, and nitrobenzene. These may be used alone or in combination of two or more. You may use in combination. Further, when a low molecular weight condensate is obtained, water, alcohol or the like may be used in combination with these solvents.

Examples of the catalyst include iron chloride (II
I), aluminum chloride, copper (II) chloride, metal salts such as potassium permanganate; persulfates such as ammonium persulfate;
Inorganic peroxides such as hydrogen peroxide, and oxidants such as organic peroxides such as benzoyl peroxide can be used.

The condensation reaction of the aminobenzene compound is carried out at a temperature not higher than the boiling point of the solvent, usually 10 to 150 ° C., preferably 30 to 1
Perform at 20 ° C. The reaction time is usually 1 to 30 hours, preferably 1 to 15 hours. After completion of the reaction, the reaction solution is poured into a poor solvent in an amount of 1 to 20 times by weight of the solution to precipitate a condensate, and the condensate is filtered and dried to obtain an aminobenzene compound condensate. Examples of the poor solvent for depositing the condensate include water, saline, ether, benzene, n-hexane, isopropanol and the like.

The reaction product of a condensate of an aminobenzene compound and p-benzoquinone includes, for example, a condensate of an aminobenzene compound and p-benzoquinone, a condensate of an aminobenzene compound, p-benzoquinone and a reaction product thereof. In a homogeneous system in which the reaction proceeds in a state where the product is completely dissolved in the reaction solvent, or a condensate of aminobenzene compound, p-
It can be obtained by reacting in a heterogeneous system in which the reaction proceeds in a state where benzoquinone and a reaction product thereof are dispersed in a reaction solvent. As the solvent, for example,
Polar solvents such as dimethylformamide, N, N-dimethylacetamide and acetonitrile; cyclic ethers such as tetrahydrofuran and dioxane; ketones such as acetone and methyl ethyl ketone; methanol, ethanol,
Alcohols such as isopropanol; water and the like,
These can be used alone or in combination of two or more.

The weight ratio of the condensate of aminobenzene compound / p-benzoquinone is usually 100/1 to 1/10, preferably 20/1 to 1/5. The total concentration of the aminobenzene compound condensate and p-benzoquinone in the solvent is preferably 1 to 50% by weight. The reaction temperature is not higher than the boiling point of the solvent, preferably 20 to 100 ° C. Reaction time is usually 1
Minutes to 30 hours may be used, preferably 1 to 10 hours. The reaction rate is, for example, mineral acid such as hydrochloric acid, sulfuric acid, phosphoric acid; NaO
It can be adjusted by adding a base such as H and KOH; preferably phosphoric acid to the reaction system. After completion of the reaction, the obtained reaction solution may be used as it is as a polymer scale adhesion preventing agent. In addition, the reaction solution is 1 for the solution.
~ 20 times the amount of poor solvent to deposit the reaction product,
A product obtained by filtering and drying the reaction product may be used as a polymer scale anti-adhesion agent. Examples of the poor solvent for precipitating a reaction product include water, saline, ether,
Benzene, n-hexane, isopropanol, etc. are mentioned.

The polymer scale adhesion preventive agent of the present invention preferably contains an inorganic colloid in addition to the reaction product. As the inorganic colloid, for example,
Gold colloid, silver colloid, sulfur colloid, ferric hydroxide colloid, stannic acid colloid, silicic acid colloid, manganese dioxide colloid, molybdenum oxide colloid, barium sulfate colloid, aluminum hydroxide colloid, vanadium pentoxide. And colloids of lithium silicate, and these can be used alone or in combination of two or more. Among them, silicic acid colloid, aluminum hydroxide colloid and the like are preferable. Particularly suitable silicic acid colloids are aqueous silica sols, methanol silica sols, butanol silica sols, ethylene glycol silica sols and DMF silica sols. The amount of the inorganic colloid is usually 100/1 to 1/100 in terms of the inorganic colloid / the reaction product weight ratio (solid content conversion).
, Preferably 10/1 to 1/10. If the amount of inorganic colloid is too small, the advantage of using it together may not be obtained.

The reaction product obtained by the reaction of such an aminobenzene compound condensate with p-benzoquinone has a low activity of the amino group contained therein as compared with a conventional aromatic amine condensate, and has a molecular weight. high. The polymer scale anti-adhesion agent of the present invention exerts remarkable scale anti-adhesiveness because it has a small effect on the polymerization system of the monomer because the activity of the amino group is low, and the amount dissolved by the monomer due to the high molecular weight. Is estimated to be small.

(Method for producing polymer using polymer scale anti-adhesion agent) In the method for producing a polymer of the present invention, a monomer having an ethylenically unsaturated double bond is added to the polymer scale anti-adhesion agent. Is a production method in which a coating film consisting of is polymerized in a polymerization vessel having an inner wall of the polymerization vessel.

For the coating film, for example, a reaction solution containing the reaction product of the above-mentioned aminobenzene compound condensate and p-benzoquinone is applied as it is, or a coating solution prepared as follows is applied to the inner wall of the polymerization vessel. It can be formed by drying.

Preparation of Coating Liquid The coating liquid can be obtained by dissolving or dispersing the reaction product of the aminobenzene compound condensate and p-benzoquinone or the reaction product and the inorganic colloid in a suitable solvent. .

The solvent for preparing the coating solution is, for example,
Water; alcohol solvents such as methanol and isobutyl alcohol; aromatic hydrocarbon solvents such as benzene, toluene, xylene; methylene chloride, dichloroethylene, 1,
Halogenated hydrocarbon solvents such as 1,2-trichloroethane; ketone solvents such as acetone and methyl ethyl ketone;
Ester solvents such as methyl formate and ethyl acetate; 1,4-
Examples include ether solvents such as dioxane and ethylene glycol monomethyl ether; polar solvents such as dimethylformamide, N, N-dimethylacetamide, and N-methylpyrrolidone. These can be used alone or in combination of two or more. Among these, water, methanol, isobutyl alcohol, acetone, dimethylformamide, or a mixed solvent thereof is preferable. The concentration of the reaction product of the aminobenzene compound condensate and p-benzoquinone in the coating solution may be usually 0.001 to 10% by weight, preferably 0.01 to 2% by weight. Further, the coating liquid further containing an inorganic colloid is 0.01 to 5% by weight in the total amount of the reaction product and the inorganic colloid (as solid content).
Those containing are preferable. In addition, as a method of adding an inorganic colloid to the reaction product, after dissolving or dispersing the reaction product in the solvent, water in advance in this solution or dispersion,
The inorganic colloid having a concentration of 1 to 10% by weight is mixed with the solvent used for this coating solution, the dispersion medium of the inorganic colloid (solid content conversion) and the like.

Formation of Coating Film To form a coating film on the inner wall surface of the polymerization vessel using the prepared coating solution, first, the coating solution is applied to the inner wall surface of the polymerization vessel, and then
For example, after sufficiently drying in the temperature range from room temperature to 100 ° C., the inner wall surface of the polymerization vessel is further washed with water if necessary. Further, the coating film is preferably formed not only on the inner wall surface of the polymerization vessel, but also on other portions where the monomer contacts during the polymerization,
Examples of such parts include stirring blades, stirring shafts, baffles, condensers, headers, search coils, bolts, nuts, and the like. Further, even at a site other than the site where the monomer comes into contact during the polymerization, the site where the polymer scale may be attached, for example, the inner surface of the equipment and piping of the recovery system of the unreacted monomer, etc. It is preferable to form a film. Examples of such a part include inner surfaces of a monomer distillation column, a condenser, a monomer storage tank, a valve, and the like. The coating film may be formed in the same manner as when it is formed on the inner wall surface of the polymerization vessel.

In this way, when a coating film is formed on the site where the monomer contacts during the polymerization and the site where other polymer scale may adhere, the adherence of the polymer scale to those sites. Is prevented. The method of applying the coating liquid to the inner wall surface of the polymerization vessel is not particularly limited, and includes, for example, brush coating, spray coating, a method of withdrawing after filling the polymerization vessel with the coating solution, and others.
It is also possible to use the automatic coating methods described in JP-B No. 55-36288, JP-B No. 56-501116, JP-B No. 56-501117, JP-A No. 59-11303, and the like.

The method of drying after coating is not limited, and for example, a method of applying hot air having an appropriately elevated temperature to the coated surface after coating; the inner wall surface of the polymerization vessel to be coated with the coating liquid and other A method may be used in which the surface is heated in advance to, for example, 30 to 80 ° C. and the coating solution is directly applied to the heated surface. When the boiling point of the solvent or dispersion medium of the coating liquid exceeds 80 ° C, it may be dried under reduced pressure if necessary. After drying, the coated surface can be washed with water if necessary. The coating thus obtained has a total coating amount after drying of usually 0.001 to 5 g / m ^2.
It is sufficient that it is 0.01 to 3 g / m ² .

The above coating operation may be carried out for every one to several batches of polymerization. The coating film formed has high durability,
Since the action of preventing the polymer scale from adhering continues, it is usually sufficient to perform the coating operation once every several batches. Thereby, the polymerization vessel can be repeatedly used without adhering the polymer scale to the inner wall of the polymerization vessel or the like.

Polymerization As described above, a coating film is formed by applying a coating treatment to the inner wall of the polymerization vessel and other portions where the monomer comes into contact during the polymerization, and then polymerization is carried out in the polymerization vessel by a conventional method. To do. That is, in addition to a monomer having an ethylenically unsaturated double bond and a polymerization initiator (catalyst), if necessary, a polymerization medium such as water, and a suspending agent, a solid dispersant, a nonionic or anionic emulsifier. Then, a dispersant and the like are charged, and then polymerization is performed by a conventional method.

Examples of the monomer having an ethylenically unsaturated double bond which is polymerized by applying the method of the present invention include:
Vinyl halides such as vinyl chloride; vinyl esters such as vinyl acetate and vinyl propionate; acrylic acid, methacrylic acid, and their esters or salts; maleic acid, fumaric acid, and their esters or anhydrides; butadiene, chloroprene, Diene monomers such as isoprene; styrene; acrylonitrile; vinylidene halide; vinyl ether; isobutene and the like.

The type of polymerization to which the method of the present invention is applied is not particularly limited, and suspension polymerization, emulsion polymerization, solution polymerization,
It is effective in both bulk polymerization and vapor phase polymerization, and is particularly suitable for polymerization in an aqueous medium such as suspension polymerization and emulsion polymerization. The method of the present invention can be particularly preferably applied to a suspension polymerization method or an emulsion polymerization method of a monomer mixture mainly containing vinyl chloride; beads of polystyrene, polymethylmethacrylate, polyacrylonitrile and the like, and a method of producing latex; SBR, NBR, CR, IR, II
A synthetic rubber production method by emulsion polymerization such as R; an ABS resin production method; an AS resin production method by suspension polymerization using a solid dispersant. Hereinafter, the general polymerization method will be specifically described by taking the cases of suspension polymerization and emulsion polymerization as examples.

First, water and a dispersant are charged into a polymerization vessel, and then a polymerization initiator is charged. Next, exhaust the inside of the polymerization vessel.
After reducing the pressure to 0.1 to 760 mmHg, the monomers are charged (at this time, the internal pressure of the polymerization vessel is usually 0.5 to 30 kgf / cm ² · G), and then the polymerization is carried out at a reaction temperature of 30 to 150 ° C. During the polymerization, one or more kinds of water, a dispersant and a polymerization initiator are added, if necessary. The reaction temperature during polymerization is
Depending on the type of monomer to be polymerized, for example, in the case of vinyl chloride polymerization, the polymerization is performed at 30 to 80 ° C, and in the case of styrene polymerization, the polymerization is performed at 50 to 150 ° C. As for polymerization, when the internal pressure of the polymerization vessel dropped to 0 to 7 kgf / cm ² · G, or there was almost no difference between the inlet temperature and the outlet temperature of the cooling water flowing in and out of the jacket equipped on the outer periphery of the polymerization vessel. When (that is, when the heat generated by the polymerization reaction disappears)
It is judged that it is completed. Water charged during polymerization,
The dispersant and the polymerization initiator are usually 20 to 500 parts by weight of water, 0.01 to 30 parts by weight of the dispersant, and 0.01 to 5 parts by weight of the polymerization initiator with respect to 100 parts by weight of the monomer.

In the case of solution polymerization, an organic solvent such as toluene, xylene or pyridine is used as a polymerization medium instead of water. A dispersant is used as needed. Other polymerization conditions are generally the same as those for suspension polymerization and emulsion polymerization.

In the case of bulk polymerization, the inside of the polymerization vessel is
After evacuation to a pressure of 0.01 to 760 mmHg, a monomer and a polymerization initiator are charged in the polymerization vessel, and polymerization is carried out at a reaction temperature of -10 to 250 ° C. For example, in the case of vinyl chloride polymerization,
It is carried out at 80 ° C. and, in the case of styrene polymerization, at 50 to 150 ° C.

When polymerization is carried out by applying the polymer scale adhesion preventing method of the present invention, it is possible to prevent the adhesion of polymer scale regardless of the material of the inner wall surface of the polymerization vessel. The adhesion of polymer scale can be prevented even when the polymerization is carried out in a steel or other steel-made polymerization vessel, a glass-lined polymerization vessel, or the like. What is added to the polymerization system can be used without any restrictions. That is, for example, t-butyl peroxy neodecanoate, bis (2-ethylhexyl) peroxydicarbonate, 3,5,5-trimethylhexanoyl peroxide, α-cumyl peroxy neodecanoate,
Cumene hydroperoxide, cyclohexanone peroxide, t-butyl peroxypivalate, bis (2-ethoxyethyl) peroxydicarbonate, benzoyl peroxide, lauroyl peroxide,
2,4-dichlorobenzoyl peroxide, diisopropyl peroxydicarbonate, α, α′-azobisisobutyronitrile, α, α′-azobis-2,4-dimethylvaleronitrile, potassium persulfate, ammonium persulfate, Polymerization initiators such as p-menthane hydroperoxide; partially saponified polyvinyl alcohol, polyacrylic acid, copolymers of vinyl acetate and maleic anhydride, cellulose derivatives such as hydroxypropylmethyl cellulose, natural or synthetic polymer compounds such as gelatin. Suspension agents such as; solid dispersants such as calcium phosphate and hydroxyapatite;
Sorbitan monolaurate, sorbitan trioleate,
Nonionic emulsifiers such as polyoxyethylene alkyl ether; anionic emulsifiers such as sodium alkylbenzenesulfonate such as sodium lauryl sulfate and sodium dodecylbenzenesulfonate; sodium dioctylsulfosuccinate; fillers such as calcium carbonate and titanium oxide; tribasic Stabilizers such as lead sulfate, calcium stearate, dibutyltin dilaurate and dioctyltin mercaptide; lubricants such as rice wax, stearic acid and cetyl alcohol; plasticizers such as DOP and DBP; mercaptans such as t-dodecylmercaptan; trichloroethylene and the like. Even in a polymerization system in which a chain transfer agent, a pH adjuster, a reducing agent such as Rongalit, iron sulfate and the like are present, the method of the present invention can effectively prevent the adhesion of polymer scale.

The polymer scale adhesion preventive agent of the present invention may be used for forming a coating film on the inner wall surface of the polymerization vessel or the like, and may be further added directly to the polymerization system. It can also be improved. In that case, it is appropriate that the addition amount of the polymer scale anti-adhesion agent is about 10 to 1000 ppm with respect to the total weight of the charged monomers. When adding, care should be taken not to affect the quality of the product polymer such as fish eye, bulk specific gravity and particle size distribution.

[0034]

EXAMPLES The present invention will be described more specifically below with reference to examples. (A) Preparation example of condensate ( preparation of condensate of aminobenzene compound)

Preparation Example 1 A 200 ml three-necked flask equipped with a stirring blade and a reflux condenser was charged with 9.3 g of aniline and 50 ml of nitrobenzene and the stirring was started. Next, a solution prepared by dissolving 2.7 g of FeCl ₃ .6H ₂ O in 50 ml of water was added, and the reaction was carried out at 80 ° C. for 5 hours. After the reaction,
The reaction solution was poured into 2000 ml of ether, and the condensate deposited was filtered under reduced pressure, washed thoroughly with water, and then dried at 50 ° C. The obtained condensate is called condensate (A) -1.

Preparation Example 2 10.8 g of m-phenylenediamine and 50 ml of DMF were charged into a three-neck flask similar to that used in Preparation Example 1 and stirring was started. Next, a solution prepared by dissolving 1.7 g of CuCl ₂ .2H ₂ O in 50 ml of water was added, and the reaction was carried out at 100 ° C. for 7 hours. After the reaction,
The reaction solution was poured into 2000 ml of 10% saline, the precipitated condensate was filtered under reduced pressure, and dried at 50 ° C. The resulting condensate is called condensate (A) -2.

Preparation Example 3 In a three-necked flask similar to that used in Preparation Example 1, 2, 4
-Diaminophenol 12.4g, N-methylpyrrolidone 50
ml was charged and stirring was started. Next, 25 ml of 30% H ₂ O ₂ was added and the reaction was carried out at 50 ° C. for 10 hours. After the completion of the reaction, the reaction solution was poured into 500 ml of 2% saline, and the precipitated condensate was filtered under reduced pressure and dried at 50 ° C. Condensate (A)-
3

Preparation Example 4 In a three-necked flask similar to that used in Preparation Example 1,
2,4-triaminobenzene 12.3g, nitrobenzene 10
ml and 40 ml of DMF were charged and stirring was started. Next, FeCl ₃ ·
2.7 g of 6H ₂ O was added, and the reaction was carried out at 100 ° C. for 5 hours. After the completion of the reaction, the reaction solution was put into 300 ml of benzene, and the precipitated condensate was filtered under reduced pressure, washed thoroughly with water, and then dried at 50 ° C. The obtained condensate is called condensate (A) -4.

Preparation Example 5 A three-necked flask similar to that used in Preparation Example 1 was charged with 10.8 g of m-phenylenediamine, 10.9 g of p-aminophenol, 20 ml of nitrobenzene, 2.6 g of anhydrous AlCl ₃ and DMF.
30 ml was charged and stirring was started. The reaction was carried out at 100 ° C for 10 hours. After the reaction is complete, add 300 ml of isopropanol to the reaction mixture.
The mixture was put into a flask, the precipitated condensate was filtered under reduced pressure, further washed thoroughly with water, and then dried at 50 ° C. Condensate obtained condensate
(A) -5.

(B) Preparation Example of Reaction Product ( Preparation of Reaction Product of Condensate of Aminobenzene Compound and p-Benzoquinone) Condensates obtained in Preparation Examples 1 to 5 in the amounts shown in Table 1
(A) -1 to (A) -5 are reacted with the amounts of p-benzoquinone also shown in Table 1 under the conditions (solvent, catalyst, reaction temperature and reaction time) shown in Table 1 to give a reaction product ( a) to (h) were produced. For comparison, the uncondensed aminobenzene compound is used instead of the condensate of the aminobenzene compound.
Reaction products (i) to (k) were prepared by reacting with benzoquinone. The reaction product was obtained in a solution state. Reaction product
The obtained solution state of (f) and (g) was used as it is in the examples described later. The reaction products (a) to (e) and (h) were prepared by pouring the reaction solution into 5% saline which was 10 times the volume of the reaction solution and stirring it sufficiently to precipitate a condensate. It was separated from the solution and made into a powder state, which was then used in the examples described later. In addition, Table 1
Among them, the reaction products marked with * do not satisfy the conditions of the present invention, and were used for Comparative Examples described later.

[0041]

[Table 1]

(C) Preparation of coating liquid As shown in Table 2, components selected from reaction products a to k
(I) is dissolved or dispersed in the solvent in the amount shown in the table, and optionally the inorganic colloid component (II) shown in the table is blended ratio (solid content conversion) and concentration (reaction product) shown in the table. And the total amount of the inorganic colloid) were added to the solvent and mixed to prepare coating solutions Nos. 1 to 25. However, coating liquid
In Nos. 4 and 8, the reaction product was not used, but the condensate (A) -1 was used instead. The coating liquids marked with * do not satisfy the conditions of the present invention, and were used in the comparative examples described later.

[0043]

[Table 2]

Examples 1 to 6 and Comparative Examples 1 to 4 (when a polymerization test was carried out only for one batch)] The inner wall of a stainless steel polymerization vessel equipped with a stirrer (internal volume of 1000 liters), stirring shaft, stirring blade, and other units. Apply the coating solution of the number (No.) shown in Table 3 (see Table 2) to the part where the polymer comes into contact,
After drying at 50 ° C. for 15 minutes, it was washed with water to form a coating film. 400 kg of water, 200 kg of vinyl chloride, 250 g of partially saponified polyvinyl alcohol, 25 g of hydroxypropylmethyl cellulose and 75 g of diisopropyl peroxydicarbonate were charged into this polymerization vessel and polymerization was carried out at 57 ° C. for 6 hours while stirring. After the completion of the polymerization, the scale adhesion amount (g / m ² ) per unit area of the inner wall surface of the polymerization vessel was measured as follows. The results are shown in Table 3.

Measurement method of polymer scale: After all scales attached to an area of 10 cm square can be visually confirmed, after scraping off with a spatula made of stainless steel and weighing,
The measured value was multiplied by 100 to obtain the scale adhesion amount per 1 m ² .

[0046]

[Table 3]

Examples 7 to 13 and Comparative Examples 5 to 7 Examples other than using a polymerization vessel having an internal volume of 20 liters and applying the coating liquid (No.) shown in Table 4 (see Table 2). 1
A coating film was formed on the polymerization vessel in the same manner as in. In the polymerization vessel, 8 kg of water, 5.2 kg of styrene monomer, 2.8 kg of methacrylic acid monomer, 8 g of partially saponified polyacrylamide and α,
24 g of α'-azobisisobutyronitrile was charged and polymerized at 90 ° C for 5 hours while stirring. After the polymerization, the amount of polymer scale attached was measured in the same manner as in Example 1. Table 4 shows the results
Shown in

[0048]

[Table 4]

Examples 14 to 19 and Comparative Examples 8 to 11 (1
Polymerization test was conducted only in batch) Example 1 was repeated except that a polymerization vessel having an internal volume of 22 liters was used and the coating solution (see Table 2) with the number (No.) shown in Table 5 was applied.
A coating film was formed on the polymerization vessel in the same manner as in. In this polymerization vessel, 10 kg of water, 2.5 kg of styrene, 1.0 kg of acrylonitrile
, SBR latex 2.4kg, Harima Kasei Kogyo Co., Ltd. synthetic rubber emulsifier (Bandis T-100P) 50g, NaOH
2.0 g, 30 g of t-dodecyl mercaptan and 5.0 g of ammonium persulfate were charged, and polymerization was carried out at 70 ° C. for 2 hours while stirring. After the polymerization was completed, the amount of polymer scale attached was measured in the same manner as in Example 1. The results are shown in Table 5.

[0050]

[Table 5]

Examples 20 to 25 (when a repeated polymerization test was carried out) A polymerization vessel having an internal volume of 20 liters was used, except that the coating solution of the number (No.) shown in Table 6 (see Table 2) was applied. Example 1
A coating film was formed on the polymerization vessel in the same manner as in. Water 9 kg, sodium dodecylbenzene sulfonate 225 in this polymerization vessel
g, t-dodecyl mercaptan 12g and potassium persulfate 1
After charging 3g and replacing with nitrogen gas, 1.3kg of styrene
, 3.8 kg of butadiene were charged and polymerized at 50 ° C. for 20 hours. After the completion of the polymerization, the polymer slurry was extracted and then the inside of the polymerization vessel was washed with water. After 15 batch polymerization, the steps from coating of the coating liquid, polymerization and washing with water are defined as 1 batch,
The polymer scale deposition amount was measured in the same manner as in Example 1. The results are shown in Table 6. In addition, in this example, the amount of scale deposition was measured for a portion located in the liquid phase portion during polymerization and a portion located near the gas-liquid interface.

Comparative Examples 12 to 15 (When Repeated Polymerization Test is Performed) The same procedure as in Example 1 is applied except that the coating solutions No. 26 to No. 29 prepared as described below are applied to the polymerization vessel. A film was formed. Then, using this polymerization vessel, styrene and butadiene were polymerized in the same manner as in Example 20, and after the completion of the polymerization, the amount of polymer scale adhesion was measured in the same manner as in Example 1.
The results are shown in Table 6.

Preparation of coating liquid No. 26 The weight ratio of m-phenylenediamine / nitrobenzene was 10
100 ml of a solution dissolved in methanol at 0/10 and a concentration of 1.0% by weight was stirred at 80 ° C. for 3 hours for reaction. To 20 ml of this reaction solution, 30 ml of methanol and 50 ml of water were added and mixed, and the pH was adjusted to 3.0 with HCl to obtain a coating solution.

Preparation of coating liquid No. 27 p-aminophenol / m-phenylenediamine / p-
Benzoquinone weight ratio 100/100/50 and concentration 2.0
100 ml of a solution prepared by dissolving 80 ml of methanol and 20 ml of water so as to have a weight percentage was stirred at 50 ° C. for 10 hours to cause a reaction. To 30 ml of this reaction solution, 60 ml of methanol and 10 ml of water were added and mixed, and NaOH was added.
The pH was adjusted to 11.0 with to prepare a coating solution.

Preparation of coating liquids No. 28 and No. 29 In the above coating liquids No. 26 and No. 27, an aqueous silica sol (20
%) Was added and mixed to obtain coating liquid No. 28,
The coating liquid was No. 29.

[0056]

[Table 6]

[0057]

EFFECTS OF THE INVENTION According to the polymer scale adhesion preventing method of the present invention, it is difficult to prevent the adhesion of the polymer scale due to its large solubility in the coating film formed of the polymer scale adhesion preventing agent. In polymerization or copolymerization of a monomer having an ethylenically unsaturated double bond, it is possible to effectively prevent the polymer scale from adhering to the inner wall surface of the polymerization vessel. In particular, even in a polymerization system containing a monomer such as styrene, α-methylstyrene, acrylic acid, acrylic acid ester, acrylonitrile, etc., which has a remarkably large solubility in the conventional coating film, it is possible to reliably prevent adhesion of polymer scale. it can. In addition, the formed coating film has high durability, and since the polymer scale adhesion preventing action lasts, it is possible to repeatedly use the polymerization vessel once the coating film has been formed, and thus the production It is possible to improve the sex. Further, in the conventional polymer scale anti-adhesion agent, the polymer scale of which the inner wall surface was glass lined was easier to attach the polymer scale than the stainless steel polymerization vessel, but the polymer scale anti-adhesion agent of the present invention By using, it is possible to effectively prevent the adhesion of the polymer scale regardless of the material of the inner wall of the polymerization vessel.

Claims (3)

[Claims] 1. A polymer scale anti-adhesion agent for polymerization of a monomer having an ethylenically unsaturated double bond, which contains a reaction product of a condensate of an aminobenzene compound and p-benzoquinone. 2. The polymer scale adhesion preventive agent according to claim 1, which further contains an inorganic colloid in addition to the reaction product. 3. A method for producing a polymer, comprising a step of polymerizing a monomer having an ethylenically unsaturated double bond in a polymerization vessel having a coating film having a polymer scale adhesion preventing property on the inner wall of the polymerization vessel. A method for producing a polymer, wherein the coating film having the polymer scale adhesion preventing property comprises the polymer scale adhesion preventing agent according to claim 1 or 2.