JPH06192303A - Agent for preventing adhesion of polymer scale, polymerizer for effectively preventing adhesion of polymer scale and production of polymer by using them - Google Patents

Abstract

PURPOSE:To obtain an inhibitor synthesized by adding a terminator during condensation between hydrazine and a quinone, capable of effectively preventing adhesion of scale by addition into a polymerizer for polymerizing an ethylenic double bond-containing monomer, and as a result, capable of giving a product free from fish eye or initial color. CONSTITUTION:This inhibitor contains a condensed material synthesized by adding a reaction terminator during a condensation reaction between hydrazine and a quinone compound. A coating film containing this synthesized material is formed in a polymerizer for polymerizing an ethylenic double bond-containing monomer. Lawson, juglone, plumbagin, etc., is used as the quinone compound and sodium hydrosulfite, etc., is used as the terminator. The termination is carried out by adding the terminator at a point of time of 70 to 95wt.% conversion in the condensation reaction between these two components in a mixture solvent of an alcohol and water at pH 9.0 to 13.0.

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 for polymerizing a monomer having an ethylenic double bond, a polymerization vessel effective for preventing the adhesion of polymer scale, and a polymer using the same. Manufacturing method.

[0002]

2. Description of the Related Art Conventionally, as a method for polymerizing a monomer having an ethylenic double bond, a suspension polymerization method, an emulsion polymerization method, a solution polymerization method, a gas phase polymerization method or a bulk polymerization method is known. . In any of these polymerization methods, adhesion of the polymer scale is likely to occur on the inner wall of the polymerization vessel, the agitator, and the like where the monomer comes into contact.

When the polymer scale adheres, the yield of the polymer, the cooling ability of the polymerization vessel, etc. are lowered, and the polymer scale is peeled off and mixed in the product, which brings about a disadvantage of degrading the quality of the product. Be done. Further, in order to remove the adhered polymer scale, not only excessive labor and time are required, but also unreacted monomer is contained in this polymer scale, so that it has become a very serious problem in recent years. There is a risk of personal injury due to the existing monomer.

As for the prevention of adhesion of the polymer scale to the inner wall of the polymerization vessel, the polarities of amine compounds, quinone compounds, aldehyde compounds, etc. have been used, as has been carried out, for example, in suspension polymerization of vinyl chloride. A method of applying a polymer scale anti-adhesion agent comprising an organic compound,
Alternatively, a method of adding these compounds to an aqueous medium is known (Japanese Patent Publication No. 45-30343). However, these methods show an effect of preventing polymer scale from adhering to repeated polymerization of about 5 to 6 batches, but when the number of polymerization batches is larger than that, the preventive effect is lost (inferior in sustainability).
There is a disadvantage that. In this respect, the use of a water-soluble catalyst has a particularly remarkable effect and is not industrially satisfactory.

In order to overcome this disadvantage, in JP-A-60-30681, a condensation product of an aromatic amine compound and an aromatic nitro compound is applied to the inner wall of the polymerization vessel or the like where the monomer comes into contact. Is proposed. When a coating film of the condensation product of this aromatic amine compound and aromatic nitro compound is formed on the inner wall surface of the polymerization vessel, etc., even if the polymerization is repeated up to about 100 to 200 batches, the scale to the liquid phase part in the polymerization vessel No adhesion occurs. Also, when a water-soluble catalyst is used, polymer scale adhesion in the liquid phase part is also prevented.

[0006]

However, there is a drawback that polymer scale adheres to the vicinity of the interface between the gas phase portion and the liquid phase portion located in the upper layer portion in the polymerization vessel. Once the polymer scale adheres to the vicinity of the interface between the gas phase part and the liquid phase part, the adhered polymer scale gradually grows as the polymerization is repeated, and finally, the polymer scale adheres to the inside of the polymer. May be mixed. Thus, when the polymer scale is mixed in the polymer, when the polymer is processed into a molded article such as a sheet, many fish eyes are generated in the resulting molded article, and the quality of the molded article is significantly deteriorated. It will be.

When the polymer obtained by polymerization is processed into a molded article such as a sheet, the molded article obtained is required to have high whiteness. That is, even if the polymer is molded into a sheet or the like without adding any coloring agent, the molded product obtained is somewhat colored. This coloring is called initial coloring, and it is desired that the coloring be as small as possible. However, since the coating film composed of the condensation product of the aromatic amine compound may be peeled off or dissolved and mixed into the polymer, the whiteness of the molded article is lowered, that is, the initial colorability is deteriorated.

The object of the present invention is to be effective not only when polymerizing a monomer having an ethylenic double bond, not only in the liquid phase part in the polymerization vessel but also in the vicinity of the interface between the gas phase part and the liquid phase part. In addition to being able to prevent the adhesion of polymer scale to a sheet, when formed into a sheet or the like, it is possible to produce a polymer having a very small number of fish eyes, and a molded product having good initial colorability. An object of the present invention is to provide a coalescing scale anti-adhesion agent, a polymerization vessel using the inhibitor, and a method for producing a polymer.

[0009]

Means for Solving the Problems In order to achieve the above object, the present invention provides (C) a reaction terminator to the reaction system during the condensation reaction of (A) hydrazine and (B) a quinone compound. Provided is a polymer scale anti-adhesion agent for polymerization of a monomer having an ethylenic double bond, which contains a condensation product obtained by addition. Further, the present invention is a polymerization vessel for the polymerization of a monomer having an ethylenic double bond, on the inner wall surface, (A) hydrazine and (B) during the condensation reaction of the quinone compound, (C) Provided is a polymerization vessel having a coating film containing a condensation product obtained by adding a reaction terminator to the reaction system. Furthermore, the present invention is a method for producing a polymer by polymerizing a monomer having an ethylenic double bond in a polymerization vessel, wherein (A) hydrazine and (B) a quinone compound are provided on the inner wall surface. During the condensation reaction, (C) in a polymerization vessel having a coating film containing a condensation product obtained by adding a reaction terminator to the reaction system, a step of performing the polymerization,
This provides a manufacturing method in which adhesion of polymer scale in the polymerization vessel is prevented.

Condensation Product The above condensation product, which is an essential component of the polymer scale anti-adhesion agent of the present invention, undergoes a condensation reaction between hydrazine (A) and a quinone compound (B) in a suitable solvent. Sometimes, it is a substance obtained by adding a reaction terminator (C) to the reaction system. The raw materials and the manufacturing method will be described below. (B) quinone compound quinone compound, for example, the following general formula (1) ~ (4)
Is a compound represented by.

[0011]

[Chemical 1]

[0012]

[Chemical 2] (Here, R ¹ is -H, -NH ₂ , -Cl, -Br, -OH, -NO ₂ ,
-COCH ₃ , -OCH ₃ , -N (CH ₃ ) ₂ or 1 to 3 carbon atoms
Represents an alkyl group, and R ² is —H, —NH ₂ , —OH, —CH ₃ ,
-COOH or an -SO ₃ H. Specific examples thereof include o- or p-benzoquinone, oxy-p-benzoquinone, chloro-p-benzoquinone, bromo-p-benzoquinone, juroquinone and chloranil.

[0013]

[Chemical 3]

[0014]

[Chemical 4] (Here, R ¹ and R ² may be the same or different,
As described above. R ³ is -H, -OH, -CH ₃ ,
-Cl, -Br, -COCH _3, represents an -OCH _3, -COOH or -SO ₃ H. ) Specifically, 6-methyl-1,4-naphthoquinone, 2-methyl-
Examples include 1,4-naphthoquinone, lawson, juglone, plumbagin, α-naphthoquinone, β-naphthoquinone and the like.

Among the above quinone compounds, preferred are lawson, juglone, plumbagin and α-naphthoquinone. The above quinone compounds can be used either individually or in combination of two or more.

(C) Reaction Stopping Agent As the reaction stopping agent (C), for example, an inorganic reducing agent is used. Specifically, hydrogen, hydrogen iodide, hydrogen bromide, hydrogen sulfide, lithium aluminum hydride, sodium borohydride, calcium borohydride, zinc borohydride,
Borohydride tetraalkylammonium, trichlorosilane, hydrides such as triethylsilane, carbon monoxide,
Lower oxides and lower oxyacid salts such as sulfur dioxide, sodium thiosulfate, sodium thiosulfite, sodium sulfite, potassium sulfite, sodium bisulfite, sodium hydrosulfite, sulfur compounds such as Rongalit, sodium sulfide, sodium polysulfide, ammonium sulfide Alkali metals such as sodium, lithium, magnesium,
Large electropositive metals such as calcium, aluminum and zinc, or their amalgams, iron (II) sulfate, tin chloride
(II), Titanium (III) trichloride, and other low-valent metal salts, phosphorus trichloride, phosphorus triiodide, trimethylphosphine, triphenylphosphine, trimethylphosphite, hexamethylphosphorus triamide, and other phosphorus Examples thereof include compounds, hydrazine, and diboranes such as diborane, ethane-1,2-diaminoborane, dimethylamineborane and pyridineborane, and substituted boranes. Preferred among these are hydrogen iodide, hydrogen bromide, sodium borohydride, sulfur dioxide, sodium thiosulfate,
Sodium thiosulfite, sodium sulfite, potassium sulfite, sodium bisulfite, sodium hydrosulfite and Rongalit. The above reaction terminators may be used alone or in combination of two or more.

Condensation Reaction The condensation product, which is an essential component of the polymer scale anti-adhesion agent of the present invention, is produced when the condensation reaction of (A) hydrazine and (B) quinone compound is proceeding in a suitable solvent. In addition, (C) a reaction terminator is added to the reaction system. Examples of the solvent for the condensation reaction include water, organic solvents such as alcohol solvents, ketone solvents, ester solvents, and mixed solvents thereof. Of these, preferred are water, an organic solvent miscible with water, and a mixed solvent of an organic solvent miscible with water and water. As the organic solvent miscible with water, methanol, ethanol, alcohol solvents such as propanol,
Acetone, ketone type solvents such as methyl ethyl ketone, ester type solvents such as methyl acetate and ethyl acetate, and the like,
Among these, alcohols are preferable. When a mixed solvent of water and an organic solvent miscible with water is used as the organic solvent, the amount of the organic solvent is preferably 50% by weight or less, more preferably 30% by weight or less.

The pH of the reaction system for carrying out the condensation reaction is usually 1 to 13. The pH adjuster can be used without particular restrictions. Further, the pH when using an aqueous medium such as water or a mixed solvent of water and an organic solvent miscible with water as a solvent for the condensation reaction is preferably
It is 7.5 to 13.5, and more preferably 9.0 to 13.0.
In that case, since hydrazine (A) exhibits alkalinity, it is not necessary to adjust the pH in most cases. pH
Examples of the alkaline compound used for the adjustment of LiOH, NaOH, KOH, Na ₂ CO ₃ , Na ₂ SiO
₃ , alkali metal compounds such as Na ₂ HPO ₄ , NH ₄ OH, and ammonium compounds.

By adding the reaction terminator (C) at an appropriate time during the condensation reaction between the component (A) and the component (B), the condensation product of the component (A) and the component (B) is condensed. The degree can be adjusted. If the condensation degree of the condensation product of the component (A) and the component (B) is too high, when the condensation product is used as the coating liquid described below, the condensation product precipitates and the coating liquid becomes non-uniform. , The effect of preventing polymer scale adhesion is reduced.

The reaction terminator (C) may be added as it is or after being dissolved in an appropriate solvent such as the solvent used in the above condensation reaction. The reaction terminator (C) is
It may be added after starting the condensation reaction with the component (B), and preferably immediately before precipitation of the condensation product of the component (A) and the component (B), that is, of the component (A) and the component (B). 70 to 95% by weight, especially when the conversion rate of the condensation reaction of the components (A) and (B) reaches 50 to 99% by weight, depending on the type and reaction rate.
Add when reached. Also, when the reaction terminator (C) is added, the condensation reaction almost stops at the time of addition,
After the addition of the component (C), the stirring is usually continued for 0 to 50 hours while maintaining the temperature at which the condensation reaction is performed.

Here, the conversion rate of the condensation reaction refers to the total charged amount of the component (A) and the component (B) (as a monomer),
This is the ratio of the amount of the components (A) and (B) that have been charged and that have disappeared due to the condensation reaction. That is, (A) component and (B) component
The total amount of (as a monomer) is a part by weight, and (A)
If the total amount of the unreacted components (A) and (B) after the start of the condensation reaction between the component and the component (B) is b parts by weight, the amount lost by the condensation reaction is (ab) parts by weight. Therefore, the conversion rate of the condensation reaction is determined by the following formula. Condensation reaction conversion rate (wt%) = {(a−b) / a} × 100

The conversion rate of the condensation reaction between the component (A) and the component (B) is
The time required to reach 50 to 99% by weight depends on the (A) component and
Although it depends on the type of the component (B) and the like, it is usually 0.1 to 80 hours from the start of the condensation reaction. In addition, the time required for the entire production of the condensation product from the start of the condensation reaction between the component (A) and the component (B) through the addition of the reaction terminator (C) to the end of the stirring is (B) component and (C) Depending on the type of components, reaction temperature, timing of addition of reaction terminator, etc., usually 0.5 to 200 at room temperature to 200 ° C
Time, preferably 5 to 100 hours at room temperature to 150 ° C.

The proportions of hydrazine (A), quinone compound (B) and reaction terminator (C) used are influenced by the types of hydrazine, quinone compound and reaction terminator, reaction temperature, reaction time and the like. The proportion of quinone compound (B) used is hydrazine (A)
The amount is preferably 0.05 to 20 parts by weight, more preferably 0.1 to 5 parts by weight, per 1 part by weight. Quinone compound (B)
If the amount is too large or too small, the effect of preventing adhesion of polymer scale of the obtained condensation product decreases. Also, a reaction terminator
The proportion of (C) used is hydrazine (A) and quinone compound.
It is preferably 0.05 to 5 parts by weight, and more preferably 0.01 to 2 parts by weight, based on 1 part by weight of the total of (B).

The polymer scale adhesion preventive agent of the present invention containing the above condensation product as an essential component is formed as a coating film, for example, on the inner wall surface of the polymerization vessel to give a polymer on the inner wall surface of the polymerization vessel. It prevents the scale from adhering.
Usually, when the coating film is formed on the inner wall surface of the polymerization vessel, it is used in the state of a solution or a dispersion liquid, that is, as a coating liquid.

Preparation of Coating Liquid The coating liquid as described above may be prepared , for example, by adding the following solvent to the solution containing the condensation product obtained by the above condensation reaction, if necessary. Further, after removing the solvent of the condensation product-containing solution, it is pulverized and the following solvent is added, or the condensation product-containing solution is poured into cold water to precipitate the condensation product, and then the precipitate is filtered. Alternatively, it may be prepared by adding the following solvent to the dried product.

The solvent used for preparing the coating solution is, for example, water; methanol, ethanol, propanol, butanol, 2-butanol, 2-methyl-1-propanol, 2-methyl-2-propanol, 3-methyl- 1
-Alcoholic solvents such as butanol, 2-methyl-2-butanol, 2-pentanol; ketone solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone;
Ester solvents such as methyl formate, ethyl formate, methyl acetate, ethyl acetate and methyl acetoacetate; ether solvents such as 4-methyldioxolane and ethylene glycol diethyl ether; furans; aprotons such as dimethylformamide, dimethylsulfoxide and acetonitrile Examples include system solvents. These are appropriately used alone or as a mixed solvent of two or more kinds.

Among the above solvents, water and a mixed solvent of water and an organic solvent miscible with water are preferable.
Examples of the organic solvent that is miscible with water among the above-mentioned organic solvents include alcohol solvents such as methanol, ethanol and propanol; ketone solvents such as acetone and methyl ethyl ketone; ester solvents such as methyl acetate and ethyl acetate. To be The content of the organic solvent when using a mixed solvent of water and an organic solvent miscible with water is flammable,
It is preferable that the amount is such that there is no danger of explosion and there is no safety problem in handling such as toxicity. Specifically, it is preferable that the organic solvent is 50% by weight or less, and further 30% by weight or less. Preferably there is.

The pH of the coating solution is preferably 3.0 to 13.0, particularly preferably 8.0 to 12.5. The pH adjuster can be used without particular limitation, and examples thereof include phosphoric acid, perchloric acid, sulfuric acid, hydrochloric acid, nitric acid, phytic acid, acetic acid, p-toluenesulfonic acid, acidic compounds such as tannic acid, lithium hydroxide, and water. Alkaline compounds such as sodium oxide, potassium hydroxide, sodium carbonate, disodium hydrogen phosphate, sodium silicate, ammonia, ethylenediamine, tetramethylenediamine, ethanolamine, diethanolamine, triethanolamine, guanidine, diethylenetriamine and triethylenetetramine. To be

The concentration of the condensation product in the coating solution is not particularly limited as long as the total coating amount described later can be obtained, but it is usually
It is 0.005 to 10% by weight, preferably 0.03 to 1% by weight.

Further, for example, cationic, nonionic and anionic surfactants can be added to this coating solution as long as the scale preventing effect is not impaired. Further, if necessary, a water-soluble polymer compound such as a cationic polymer compound, an anionic polymer compound, an amphoteric polymer compound may be added.

Examples of the cationic polymer compound include polyvinylamine, polyethyleneamine, polyethyleneimine, polyacrylamide, N-vinyl-2-pyrrolidone-acrylamide copolymer, dimethyl diamyl ammonium chloride cyclized polymer, and dimethyl. Cyclic polymer of diethylammonium bromide, Cyclic polymer of diallylamine hydrochloride, Cyclic copolymer of dimethyldiallylammonium chloride and sulfur dioxide, Polyvinylpyridine, Polyvinylpyrrolidone, Polyvinylcarbazole, Polyvinylimidazoline, Polydimethylaminoethyl acrylate , Polydimethylaminoethylmethacrylate, polydiethylaminoethylacrylate, polydiethylaminoethylmethacrylate, etc. have a nitrogen atom in the side chain and Atoms cationic polyelectrolyte bearing a charged positively, and the like.

Examples of the amphoteric polymer compound include amphoteric polymer compounds such as glue, gelatin, casein and albumin. As the anionic polymer compound,
For example, sulfomethylated polyacrylamide; polyacrylic acid; alginic acid, acrylamide-vinyl sulfonic acid copolymer, polymethacrylic acid, polystyrene sulfonic acid, or the like, or alkali metal salts or ammonium salts thereof; for side chains such as carboxymethyl cellulose. Examples thereof include anionic polymer compounds having a carboxyl group or a sulfonic acid group.

Further, an inorganic compound may be appropriately added to the coating solution, if necessary, as long as it does not impair the scale preventing action. Examples of inorganic compounds that can be added include orthosilicic acid, metasilicic acid, mesodisilicate, mesotrisilicic acid, mesotetrasilicic acid, sodium metasilicate, sodium orthosilicate, sodium disilicate, sodium tetrasilicate, and water glass. Silicic acids and silicates; oxyacid salts of metals selected from alkaline earth metals such as magnesium, calcium and barium, zinc group metals such as zinc, aluminum group metals such as aluminum, platinum group metals such as platinum, and acetic acid. Examples thereof include metal salts such as salts, nitrates, hydroxides and halides; inorganic colloids such as ferric hydroxide colloid, silicic acid colloid, barium sulfate colloid and aluminum hydroxide colloid. The above-mentioned inorganic colloid may be prepared by, for example, mechanical grinding, irradiation with ultrasonic waves, electrical dispersion and chemical method.

Formation of coating film To form a coating film on the inner wall surface of the polymerization vessel using the coating solution prepared as described above, first, the coating solution is applied to the inner wall surface of the polymerization vessel, and then, for example, at room temperature. After thoroughly drying in the temperature range from 1 to 100 ° C, further wash with water if necessary.

Further, it is preferable that the coating film is applied not only to the inner wall surface of the polymerization vessel, but also to other portions where the monomer contacts during the polymerization. For example, stirring blades, stirring shafts, baffles, condensers, headers, search coils, bolts, nuts, etc. may be mentioned. More preferably, the coating solution is a site other than the site where the monomer contacts during the polymerization, but a site where the polymer scale may adhere, for example, the inner surface of the device and piping of the recovery system for the unreacted monomer. For example, it is better to form the coating film. Specifically, a monomer distillation column, a condenser,
Inner surfaces such as a monomer storage tank and a valve are included.

The method of applying the coating solution to the inner wall surface of the polymerization vessel is not particularly limited, and examples thereof include brush coating, spray coating, and the method of withdrawing after filling the polymerization vessel with the coating solution. 57-61001, 55-36288
No. 56-501116, No. 56-501117, JP-A-59-
The automatic coating method described in No. 11303 can also be used.

There is no limitation on the method of drying the wet surface due to the application of the coating solution, and the following method can be used, for example. That is, after applying the coating liquid, a method of applying an appropriately heated warm air to the coating surface, or the inner wall surface of the polymerization vessel and the other surface to be coated with the coating liquid are heated in advance to, for example, 30 to 80 ° C. Alternatively, a method of directly applying the coating liquid to the heated surface can be used. After drying the coated surface, the coated surface is washed with water as needed.

The coating film thus obtained has a total coating amount after drying of usually 0.001 to 5 g / m ² , particularly 0.05 to ² g / m ^2.
Is preferred.

The above coating operation may be carried out every 1 to 10 or more batches of polymerization. Since the formed coating film has high durability and the action of preventing the polymer scale from adhering continues, it is not always necessary to perform it for each batch of polymerization, so that the productivity is improved.

Polymerization As described above, a coating film is formed by applying a coating treatment to the inner wall of the polymerization vessel, and preferably to other portions where the monomer contacts during the polymerization, and then, in a usual manner in the polymerization vessel. Polymerize. That is, in addition to a monomer having an ethylenic 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, etc. A dispersant and the like are charged, and then polymerization is performed by a conventional method.

Examples of the monomer having an ethylenic double bond to be polymerized by applying the method of the present invention include vinyl halide such as vinyl chloride; vinyl ester 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; diene-based monomers such as butadiene, chloroprene, isoprene; styrene, acrylonitrile, vinylidene halide, vinyl ether, etc. To be These are one kind alone or 2
Used in combination of two or more species.

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 general polymerization method will be specifically described below 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, the inside of the polymerization vessel was evacuated and the pressure was reduced to 0.1 to 760 mmHg, and then monomers were charged (at this time, the internal pressure of the polymerization vessel was
Usually 0.5 to 30 kgf / cm ² · G), then 30 to 150
Polymerize at reaction temperature of ° C. During the polymerization, if necessary,
One or more of water, a dispersant and a polymerization initiator are added. Further, the reaction temperature at the time of polymerization varies depending on the type of monomer to be polymerized, for example, in the case of vinyl chloride polymerization, the polymerization is carried out at 30 to 80 ° C., and in the case of styrene polymerization, it is 50
Polymerize at ~ 150 ° C. For polymerization, the internal pressure of the polymerization vessel is 0 to 7 kg.
When it decreases to f / cm ² · G or when there is almost no difference between the inlet temperature and the outlet temperature of the cooling water that flows in and out of the jacket installed on the outer periphery of the polymerization vessel (that is, the heat generated by the polymerization reaction disappears). It is judged that it has been completed. Water, a dispersant, and a polymerization initiator charged during polymerization are usually 20 to 500 parts by weight of water, 0.01 to 30 parts by weight of a dispersant, and 0.01 to 5 parts by weight of a polymerization initiator with respect to 100 parts by weight of a monomer. It is a department.

In the case of solution polymerization, an organic solvent such as toluene, xylene or pyridine is used instead of water as a polymerization medium. 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 evacuated to a pressure of about 0.01 to 760 mmHg, then the monomer and the polymerization initiator are charged into the polymerization vessel, and the temperature is -10 to 250 ° C.
Polymerize at the reaction temperature of. For example, in the case of vinyl chloride polymerization at 30-80 ° C, in the case of styrene polymerization 50-150 ° C.
It is carried out at ° C.

When polymerization is carried out by applying the polymer scale adhesion prevention method of the present invention, the adhesion of polymer scale can be prevented 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.

The additives 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-cumylperoxy neodecanoate, cumene hydroperoxide,
Cyclohexanone peroxide, t-butyl peroxypivalate, bis (2-ethoxyethyl) peroxydicarbonate, benzoyl peroxide, lauroyl peroxide, 2,4-dichlorobenzoyl peroxide, diisopropyl peroxydicarbonate,
Polymerization initiators such as α, α′-azobisisobutyronitrile, α, α′-azobis-2,4-dimethylvaleronitrile, potassium peroxodisulfate, ammonium peroxodisulfate and p-menthane hydroperoxide; partial ken Suspending agents for 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; solid dispersions of calcium phosphate, hydroxyapatite, etc. Agents; nonionic emulsifiers such as sorbitan monolaurate, sorbitan trioleate and polyoxyethylene alkyl ethers; sodium alkylbenzene sulfonates such as sodium lauryl sulfate and sodium dodecylbenzene sulfonate; dioctyl sulfosuccinic acid Anionic emulsifiers such as thorium; fillers such as calcium carbonate and titanium oxide; stabilizers such as tribasic lead sulfate, calcium stearate, dibutyltin dilaurate, dioctyltin mercaptide; lubricants such as rice wax, stearic acid and cetyl alcohol; DDP: a plasticizer such as DBP; a mercaptan such as t-dodecyl mercaptan; a chain transfer agent such as trichlorethylene; and a polymerization system in which a pH adjusting agent and the like are present, the method of the present invention effectively adheres the polymer scale Can be prevented.

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, whereby the scale prevention effect is improved. You can also let it. In this case, the amount of the polymer scale anti-adhesion agent added is appropriately 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.

[0048]

EXAMPLES Production Example 1 Production of Condensation Product No. 1 A pressure resistant reactor was charged with 800 g of water, 200 g of methanol and 5 g of hydrazine and stirred at room temperature to dissolve hydrazine in a water-methanol mixed solvent. 5 g of α-naphthoquinone as a quinone compound (B) was added to the water-methanol solution thus obtained, and the reaction mixture obtained was heated to 25 ° C. After the reaction mixture was reacted at 25 ° C for 10 hours, 1 g of sodium hydrosulfite was added as a reaction terminator (C) to 99 g of water.
The solution dissolved in was added to the reaction mixture. The condensation reaction conversion rate of the hydrazine and the quinone compound when the addition of the component (C) was started was measured by the following method and was found to be 98% by weight. The solution to which the reaction terminator (C) had been added as described above was stirred for another 30 hours, and then the solution was cooled. In this way, a solution of the condensation product No. 1 was obtained.

Measurement of the conversion rate of condensation reaction Using liquid chromatography, unreacted hydrazine and quinone compounds in the condensation reaction solution (condensation product No. 1,
α-naphthoquinone) was quantified. The condensation reaction conversion rate was determined as follows. The total amount of hydrazine and quinone compound charged is ag. Further, the total amount of unreacted hydrazine and quinone compound quantified as described above is represented by bg. The condensation reaction conversion rate is calculated by the formula: Condensation reaction conversion rate (% by weight) = {(ab) / a} × 100.

[0050] In the Preparation of the condensation product Nanba2～10, using a solvent as shown in the quinone compound (B) and a reaction terminating agent (C) and Table 2 shown in Table 1, the condensation product No. A condensation product was produced in the same manner as in the production of 1.
Table 2 shows (A) + (B) total concentration, (A) :( B) ratio, [(A) + (B)]:
(C) ratio, reaction temperature, elapsed time from the start of the condensation reaction between the (A) component and the (B) component until the addition of the (C) component ((C) component addition start time), (C) component (A) when the addition of
Conversion rate of the condensation reaction between the component and the component (B), the stirring time after addition of the component (C), from the start of the condensation reaction between the component (A) and the component (B)
Time required to complete stirring after adding component (C)
(Production time) is shown.

[0051]

[Table 1]

[0052]

[Table 2]

Example 1 (Experiment Nos. 101 to 110) Polymerization was carried out as follows using a stainless steel polymerization vessel equipped with a stirrer and having an internal volume of 1000 liters. In each experiment, a coating solution was prepared using the condensation product and the solvent shown in Table 3 so that the conditions (solvent composition, concentration of the condensation product) shown in Table 3 would be satisfied. The coating liquid is applied to the inner wall of the polymerization vessel and the stirring shaft,
Apply to the stirring blade and other parts where the monomer contacts during polymerization,
After heating at 40 ° C. for 15 minutes and drying to form a coating film, the inside of the polymerization vessel was washed with water.

Then, in each experiment, 400 kg of water, 200 kg of vinyl chloride, and 250 parts of partially saponified polyvinyl alcohol were placed in a polymerization vessel in which a coating film was formed by coating as described above.
g, hydroxypropyl methylcellulose 25 g and 3,
70 g of 5,5-trimethylhexanoyl peroxide was charged and polymerized at 66 ° C. for 6 hours while stirring. After the polymerization was completed, the produced polymer and unreacted monomer were recovered, and the inside of the polymerization vessel was washed with water to remove the residual resin.

Thereafter, the coating operation was not performed, and the above-mentioned polymerization and washing in the polymerization vessel were regarded as one batch, and the same operation was repeated for the number of batches shown in Table 4, and after the final batch was completed, the liquid phase part in the polymerization vessel was repeated. The amount of polymer scale attached and the amount of polymer scale attached in the vicinity of the interface between the gas phase portion and the liquid phase portion were measured by the following methods for each experiment. The results are shown in Table 4.

Measurement of polymer scale The scale adhering to a 10 × 10 cm area on the inner wall of the polymerization vessel was scraped off with a spatula and weighed with a balance. Weighing value 1
It was multiplied by 00 to obtain the scale adhesion amount per 1 m ² .

Further, the number of fish eyes when the polymer obtained in each experiment was molded into a sheet was measured by the following method. The results are shown in Table 4.・Fish eye measurement 100 parts by weight of the obtained polymer, dioctyl phthalate (DO
P) 50 parts by weight, dibutyltin dilaurate 1 part by weight, cetyl alcohol 1 part by weight, titanium oxide 0.25 parts by weight, carbon black 0.05 parts by weight A mixture prepared at a mixing ratio is kneaded at 150 ° C. for 7 minutes using a 6 inch roll. After that, the sheet was formed into a sheet having a thickness of 0.2 mm, and the number of fish eyes contained in 100 cm ^{2 of the} obtained sheet was examined by a light transmission method.

Further, the lightness index (L value) was measured by the following method in order to evaluate the initial colorability when the polymer obtained in each experiment was molded into a sheet. The results are shown in Table 4. -Measurement of lightness index (L value) 100 parts by weight of the obtained polymer, stabilizer (TS manufactured by Akishima Chemical Co., Ltd., TS
-101) 1 part by weight, stabilizer (C-100J, manufactured by Katsuta Kako Co., Ltd.) 0.5
After kneading 5 parts by weight and 50 parts by weight of dioctyl phthalate as a plasticizer with a two-roll mill at 160 ° C. for 5 minutes,
Form a sheet with a thickness of 1 mm. Next, the formed sheet is 4
Put in a mold of × 4 × 1.5cm, 160 ℃, 65 ~ 70kgf / cm ²
Heat and pressure mold for 0.2 hours to prepare a sample for measurement. For this sample, the lightness index L in the Hunter color difference formula described in JIS Z 8730 (1980) was determined, and the larger the L value, the higher the whiteness, that is, the better the initial colorability. L
The value is obtained as follows. Standard light C, photoelectric colorimeter (Nippon Denshoku Industries Co., Ltd., according to JIS Z 8722)
The stimulus value Y of the XYZ color system is obtained by the stimulus value direct reading method using a Z-1001DP colorimetric color difference meter. As the geometric condition of illumination and light reception, condition d described in JIS Z 8722, Section 4.3.1 was adopted. From the obtained stimulation value Y, JIS Z 8730
The L value is calculated by the formula: L = 10Y ^1/2 described in (1980).

[0059]

[Table 3]

[0060]

[Table 4]

Example 2 (Experiment Nos. 201 to 208) Polymerization was carried out as follows using a stainless steel polymerization vessel equipped with a stirrer and having an internal volume of 20 liters. In each experiment, a coating liquid was prepared using the condensation products and the solvents shown in Table 5 so that the conditions (solvent composition, concentration of the condensation products) shown in Table 5 were satisfied. The coating liquid is applied to the inner wall of the polymerization vessel and the stirring shaft,
Apply to the stirring blade and other parts where the monomer contacts during polymerization,
After heating at 40 ° C. for 15 minutes and drying to form a coating film, the inside of the polymerization vessel was washed with water.

Next, in each experiment, 9 kg of water, 225 g of sodium dodecylbenzene sulfonate, 12 g of t-dodecyl mercaptan and 13 g of potassium peroxodisulfate were placed in the polymerization vessel in which the coating film was formed by the coating treatment as described above. Was charged, and the inside of the polymerization vessel was replaced with nitrogen gas.
kg and 3.8 kg of butadiene were charged and polymerized at 50 ° C. for 20 hours. After the polymerization was completed, the produced polymer and unreacted monomer were recovered, and the inside of the polymerization vessel was washed with water to remove the residual resin.

Thereafter, the coating operation was not performed, and the above-mentioned polymerization and washing in the polymerization vessel were regarded as one batch, and the same operation was repeated for the number of batches shown in Table 6, and after the end of the final batch, the liquid phase portion in the polymerization vessel was repeated. The amount of polymer scale attached and the amount of polymer scale attached near the interface between the gas phase part and the liquid phase part were determined in the same manner as in Example 1 for each experiment. The results are shown in Table 6
Shown in. Further, in order to evaluate the initial colorability when the polymer obtained in each experiment is formed into a sheet, the lightness index (L
The value) was measured by the following method. The results are shown in Table 6.

Measurement of lightness index (L value) To 1 kg of the obtained polymer latex, 1 kg of a 2% magnesium sulfate solution was added to perform coagulation precipitation, and then the precipitate was filtered off. The precipitate separated by filtration was washed with hot water at 80 to 90 ° C. for 2 to 3 times and then dried at 40 ° C. for 25 hours using a vacuum dryer to obtain a resin. The obtained resin is put into a 9 × 9 cm, 0.1 cm thick mold, heated at 195 ° C. and 50-60 kgf / cm ² for 0.2 hours, and pressure molded at a final pressure of 80 kgf / cm ² to obtain a measurement sample. It was made.
The lightness index L of this sample was determined in the same manner as in Example 1.

[0065]

[Table 5]

[0066]

[Table 6]

[0067]

According to the present invention, it is possible to effectively prevent the adhesion of polymer scale not only in the liquid phase portion in the polymerization vessel but also in the vicinity of the interface between the gas phase portion and the liquid phase portion. Therefore, when the present invention is applied to carry out the polymerization, it is not necessary to carry out the work of removing the polymer scale for each polymerization, thereby improving the productivity. When a polymer obtained by applying the present invention for polymerization is molded into a sheet or the like, a molded product having extremely few fish eyes can be obtained. Furthermore, the molded product has good initial colorability. Specifically, the lightness index (L value) in the Hunter color difference formula described in JIS Z 8730 (1980) is, for example, 70 or more for vinyl chloride polymers and 80 or more for SBR.

Claims (3)

[Claims] 1. An ethylene comprising a condensation product obtained by adding (C) a reaction terminator to the reaction system during the condensation reaction between (A) hydrazine and (B) quinone compound. For preventing polymerization of a monomer having a polymerizable double bond. 2. A polymerization vessel for polymerizing a monomer having an ethylenic double bond, wherein the (C) reaction is carried out on the inner wall surface during the condensation reaction of (A) hydrazine and (B) quinone compound. A polymerization vessel having a coating film containing a condensation product obtained by adding a terminating agent to the reaction system. 3. A monomer having an ethylenic double bond,
A method for producing a polymer by polymerization in a polymerization vessel, wherein (C) a reaction terminator is added to the reaction system during the condensation reaction of (A) hydrazine and (B) a quinone compound on the inner wall surface. A production method comprising the step of carrying out the above-mentioned polymerization in a polymerization vessel having a coating film containing the condensation product thus obtained, whereby the adhesion of polymer scale in the polymerization vessel is prevented.