JPH05178911A - Polymer scale deposition inhibitor and method for preventing polymer scale depositi0n using the same - Google Patents

Abstract

PURPOSE:To effectively prevent deposition of a polymer scale on the inner wall and other parts of a polymerizer by using a scale deposition inhibitor obtained by mixing an aromatic compound or dye having a specific group with an alkali metal salt and ammonium salt of poly(vinylsulfuric acid). CONSTITUTION:The title inhibitor comprises an aromatic compound and/or a dye each having at least one of a primary amino group, a secondary amino group, a tertiary amino group, a quaternary ammonium group, and an azo group and at least either of an alkali metal salt and ammonium salt of poly(vinylsulfuric acid). It is a useful polymer scale deposition inhibitor for use in the polymerization of ethylenic monomers including a haloethylene of the formula (where X is a halogen and R is H or a halogen).

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a polymer scale anti-adhesion agent and a polymer scale for polymerizing a monomer having an ethylenic double bond containing haloethylene such as vinyl halide and vinylidene halide as an essential component. The present invention relates to a method for preventing adherence.

[0002]

2. Description of the Related Art In a method for producing a polymer by polymerizing a monomer in a polymerization vessel, it is known that the polymer adheres to the inner wall surface of the polymerization vessel as a scale. When polymer scale adheres to the inner wall surface of the polymerization vessel, the yield of the polymer decreases, the cooling capacity of the polymerization vessel decreases, and the quality of the product polymer deteriorates due to the adhered polymer scale peeling and mixing into the product. And the like, and further disadvantageous in that much labor and time are required for removing the polymer scale. Moreover, since the polymer scale contains unreacted monomers,
Workers may be exposed to this and cause physical disability.

Heretofore, as a method for preventing the adhesion of the polymer scale to the inner wall surface of the polymerization vessel in the polymerization of the monomer having an ethylenic double bond, an appropriate substance is used as the polymer scale adhesion preventing agent. A method of applying to the inner wall surface is known. Examples of the substance suitable as the polymer scale adhesion preventive agent include, for example, a specific polar compound (Japanese Patent Publication No.
-30343), dyes or pigments (Japanese Examined Patent Publication No. 45-30835,
52-24953), aromatic amine compounds (JP-A-51-5088)
No. 7), a reaction product of a phenolic compound with an aromatic aldehyde, and the like (JP-A-55-54317).

[0004]

However, in the method using the above-mentioned conventional polymer scale anti-adhesion agent, a monomer having an ethylenic double bond containing haloethylene such as vinyl chloride and vinylidene chloride as an essential component is used. In polymerisation or copolymerisation it is hard to say that scale-stick prevention is always satisfactorily achieved. That is, in the polymerization of haloethylene or the polymerization of a monomer mixture containing it as a main component, the type of polymerization initiator, chain transfer agent, suspending agent, other additives, or the polymerization type, the material of the inner wall of the polymerization vessel The scale prevention effect varies depending on various conditions such as. Therefore, it is desired to develop a more excellent scale inhibitor that is not affected by the polymerization conditions.

[0005]

The object of the present invention is to polymerize or copolymerize a monomer having an ethylenic double bond containing haloethylene as an essential component such as vinyl chloride into the inner wall of a polymerization vessel or the like. It is an object of the present invention to provide a polymer scale anti-adhesion agent that can effectively prevent scale adhesion, and a method for preventing polymer scale adhesion.

[0006] That is, the present invention provides (A) a primary, secondary or tertiary amino group,
An aromatic compound having at least one group selected from the group consisting of quaternary ammonium groups and azo groups, and / or a dye having at least one group selected from the above group,
And (B) at least one selected from the alkali metal salts and ammonium salts of polyvinyl sulfate, represented by the general formula (I):

[Chemical 2] [Here, X represents a halogen atom such as fluorine and chlorine, and R represents a hydrogen atom or a halogen atom such as fluorine and chlorine. ] A polymer scale adhesion preventive agent for polymerizing a monomer having an ethylenic double bond containing haloethylene as an essential component.

Further, the present invention is a method for preventing adhesion of polymer scale in the polymerization of a monomer having an ethylenic double bond containing haloethylene represented by the general formula (I) as an essential component in a polymerization vessel. The inner wall surface of the polymerization vessel is previously coated with (A) the aromatic compound and / or dye, and (B) at least one selected from the alkali metal salts and ammonium salts of polyvinyl sulfate. Provided is a method for preventing adhesion of polymer scale, which comprises a step of performing the above-mentioned polymerization in a polymerization vessel in which a film is formed.

(A) Aromatic Compound and / or Dye The aromatic compound and / or dye which is the component (A) of the polymer scale adhesion preventive agent of the present invention is a primary, secondary, or tertiary compound. An aromatic compound having at least one group selected from the group consisting of an amino group, a quaternary ammonium group and an azo group, or a dye having this group. Examples of the aromatic compound having the above group include aromatic amines such as diaminodiphenylamine, ethylenedianiline, and diaminonaphthalene, acridines, acridines such as diaminoacridine, phenazines, phenazines such as aminophenazine, aminoazobenzene, and hydroxy. Examples thereof include azobenzenes such as azobenzene, hydrochlorides or sulfates thereof, and alkaloids such as berberine hydrochloride.

Examples of the dyes having the above groups include CI Solvent Yellow 2,4,5,6,14,15.
16, 19, 21, 33, 56, 61, 80; CI Solvent Orange 1, 2, 14, 37, 40, 44, 45; CI Solvent Red 1, 3, 8, 23, 24, 25, 27, 30, 49, 81, 82, 83, 8
4, 100, 121; CI Solvent Brown 3, 5, 20, 37;
CI Solvent Black 3, 5, 7, 22, 23; CI Acid Black 123; CI Disperse Yellow 1,
3, 4, 5, 7, 31, 33, 49, 50, 60, 61, 64, 66, 7
1, 72, 76, 78, 79; CI Disperse Orange 1, 3,
5, 11, 13, 20, 21, 30, 32, 41, 43, 45, 46, 49, 5
0, 51; CI Disperse Red 1, 4, 5, 7, 11, 1
2, 13, 15, 17, 43, 52, 53, 54, 55, 56, 58, 59, 60,
65, 72, 73, 74, 75, 76, 80, 82, 84, 88, 90, 91, 9
2, 97, 99, 101, 103, 113, 116, 117, 122, 125, 126,
127, 128, 129; CI Disperse Violet 1, 4,
8, 10, 18, 23, 24, 26, 28, 30, 33, 37, 38; CI Disperse Blue 1, 5, 6, 43, 44, 88, 96; CI Disperse Brown 3, 5; CI Di Spurs Black 1, 2, 10, 26, 27, 28, 29, 30, 31; CI Basic Red 2, 12; CI Basic Blue 1, 6, 7, 9,
12, 16, 24, 25; CI Basic Black 2; CI Basic Orange 2, 14, 15; CI Basic Violet 10, 14; CI Basic Yellow 1, 4, 6; CI Basic Green 5, 12; CI Basic Brown 1;
In addition, a condensate of an aromatic amine compound and an aromatic nitro compound, for example, an aromatic amine compound and an aromatic nitro compound described in JP-B-60-30681, in the presence of a specific condensation catalyst at 100 to 250 ° C. The condensate obtained by condensing in. These aromatic compounds and dyes can be used alone or in combination of two or more.

Among these, preferred as aromatic compounds are diaminodiphenylamine, diaminonaphthalene, diaminoacridine, aminoazobenzene and berberine hydrochloride. Preferred dyes are
CI Solvent Black 3, 5, 7, 22, CI Basic Black 2, CI Basic Orange 14, and Japanese Patent Sho
Among the condensates described in 60-30681, the general formula:

[Chemical 3] [Wherein R ¹ is -H, -NH ₂ , -Cl, or -NH -C ₆ H ₅ ,
Represents -NH -C ₆ H ₄ -OH, R ² is -H, -NH ₂ , OH or
-Represents CH ₃ . ] And an aromatic amine compound represented by the general formula:

[Chemical 4] (Here, R ³ is -H, -OH, -OCH ₃ , -OC ₂ H ₅ ,, -Cl,
Represents -COOH or -NH ₂ . ] A condensate obtained by reacting an aromatic nitro compound represented by the following at 100 to 250 ° C in the presence of a condensation catalyst, specifically the condensate described in the publication.
No. 1 to 21. Particularly preferred dyes are CI solvent black 3, 5, 7, 22 and condensate Nos. 1, 4, 11, 12, 14 and 17 described in JP-B-60-30681.

(B) Polyvinyl Sulfate Polyvinyl sulfate, which is the component (B) of the polymer scale adhesion preventive agent of the present invention, has a polymerization degree of 500 or more, and further 1,000 or more in that a more excellent scale adhesion preventing effect can be obtained. ~ 5,000
It is desirable to use the one. As this polyvinyl sulfate, for example, those having a sulfonation rate of 90 to 95%, which are represented by the following structural formulas, can be used.

[Chemical 5] (Here, M represents an alkali metal such as K or Na or an ammonium ion).

(C) Naphthoquinone Natural Dye In one preferred embodiment of the present invention, the polymer scale inhibitor or the coating film formed on the inner wall surface of the polymerization vessel further contains (C) a naphthoquinone natural dye. To be done. The (C)
The addition of the components improves the effect of preventing scale adhesion and its durability.

The polymer scale adhesion preventive agent (C) of the present invention
As the naphthoquinone-based natural pigments, naphthoquinones such as Lawson, Yugulon, and Plumbagin; naphthazarin, 2,3-dihydroxynaphthazarine, 2-methylnaphthazarin, naphthopurpurin, 2-hydroxy-3-methylnaphtha Zarin, 2-hydroxy-3-ethylnaphthazarine, 2-hydroxy-3-acetylnaphthazarine, 2,7-dimethylnaphthazarine, alkannan, echinochrome A,
Naphthazarins such as spinochrome A; alkannin,
Shikonin, acetyl shikonin, isobutyl shikonin,
Examples include shikonins such as β, β′-dimethylacryl shikonin, β-hydroxyisovaleryl shikonin, and teracryl shikonin; and derivatives thereof. These can be used alone or in combination of two or more.

Of these, preferred are naphthopurpurin, alkannan, 2,3-dihydroxynaphthazarine, shikonin, and all shikonin derivatives, and particularly preferred are shikonin and its derivatives. Since shikonins and their derivatives are contained in a natural extract from purple root, the extract can be used. Some of the shikonins have recently been mass produced and marketed using biotechnology. This polymer scale adhesion inhibitor is
For example, by being formed as a coating film on the inner wall surface of the polymerization vessel, etc., it is used to prevent scale adhesion to the inner wall surface of the polymerization vessel.

The polymer scale anti-adhesion agent of the present invention is effective for preventing scale adhesion (A), (B) and (C).
In addition to the components, if necessary, a solvent, a surfactant, a water-soluble polymer compound, an organic or inorganic pH adjusting agent, etc. can be included. Usually, when the coating film is formed on the inner wall surface of the polymerization vessel, it is used in a solution state, that is, as a coating liquid.

In the polymer scale adhesion preventive agent of the present invention,
The content ratio of (B) component to (A) component is 100% of (A) component.
It is usually 1 to 100,000 parts by weight, preferably 10 to 10,000 parts by weight, per part by weight. Also, for the (A) component
The content ratio of the component (C) is usually 100 parts by weight of the component (A).
It is 0.1 to 5000 parts by weight, preferably 1 to 500 parts by weight. If the content ratio of the component (B) or the component (C) with respect to the component (A) is outside the above-mentioned normal range, it is difficult to obtain a good scale preventing effect by the combined use. On the other hand, if the ratio of the component (B) is out of the above range, the component (A) may form a precipitate in the coating liquid, resulting in instability of the coating liquid. It is difficult to form a simple coating film.

Preparation of coating liquid The coating liquid as described above contains the above-mentioned component (A), component (B) and
It is prepared by adding the component (C) to a suitable solvent. As a solvent used for the preparation of such a coating liquid,
For example, water; methanol, ethanol, propanol,
Butanol, 2-butanol, 2-methyl-1-propanol, 2-methyl-2-propanol, 3-methyl-
Alcohols such as 1-butanol, 2-methyl-2-butanol and 2-pentanol; ketones such as acetone, methyl ethyl ketone and methyl isobutyl ketone; ethers such as 4-methyldioxolane and ethylene glycol diethyl ether; methyl formate, Esters such as ethyl formate, methyl acetate, and methyl acetoacetate; furans such as tetrahydrofuran, furfural, furfuryl alcohol, and tetrahydrofurfuryl alcohol; aliphatic hydrocarbons such as n-hexane and n-heptane; toluene, benzene, Aromatic hydrocarbons such as xylene; methylene chloride, 1-chlorobutane, amyl chloride, ethylene dichloride,
Halogenated hydrocarbons such as 1,1,2-trichloroethane; aprotic organic solvents such as acetonitrile, formamide, dimethylformamide, dimethyl sulfoxide, N-methylpyrrolidone and the like. These are appropriately used alone or as a mixed solvent of two or more kinds.

Among these solvents, particularly preferable ones are
Water; alcohol solvents such as methanol and ethanol; and mixed solvents thereof. Component (A) in coating liquid, (B)
The total concentration of the components and, in some cases, the component (C) is not particularly limited as long as the total coating amount after drying described below can be obtained, but is usually 0.0001 to 5% by weight, preferably about 0.001 to 2% by weight. .. The concentration of component (C) in the coating solution is
Usually, it is 0.0001 to 5% by weight, preferably 0.001 to
0.5% by weight. If the concentration of the component (C) is out of this range, for example, if it is too large, the component (C) may form a precipitate in the coating solution, and a good coating film should be formed on the inner wall surface of the polymerization vessel. Is difficult. On the other hand, when the amount is too small, it is difficult to obtain a good effect of the combined use of the component (C) in preventing scale. The above-mentioned coating solution preferably contains a water-soluble polymer compound as the component (D), and further contains p as the component (E).
The H adjuster is added so that the pH is 7 or less, more preferably 6 or less.

Examples of the water-soluble polymer compound (D) include a hydroxyl group-containing polymer compound, an amphoteric polymer compound, an anionic polymer compound, a cationic polymer compound, and the like. Among them, a hydroxyl group-containing polymer compound is preferable. Examples include polymer compounds and cationic polymer compounds.

Examples of the hydroxyl group-containing polymer compound include starches such as amylose, amylopectin, dextrin, oxidized starch, acetyl starch, nitrostarch, methyl starch, carboxymethyl starch and derivatives thereof; pectic acid, protopectin, Hydroxyl group-containing vegetable slime polysaccharides such as pectinic acid, alginic acid, laminarin, fucoidin, agar and carrageenin; hydroxyl group-containing animal slime polysaccharides such as hyaluronic acid, chondroitin sulfate, heparin, keratosulfate, chitin, caronine and limacoitin sulfate Nucleic acids such as ribonucleic acid and deoxyribonucleic acid; methyl cellulose;
Ethyl cellulose, carboxymethyl cellulose, glycol cellulose, benzyl cellulose, cyanoethyl cellulose, methylene ether of cellulose, triphenylmethyl cellulose, formyl cellulose, cellulose acetate, cellulose propionate, cellulose butyrate, cellulose acetate propionate, cellulose sulfonate, cellulose carbamate. , Cellulose derivatives such as nitrocellulose, cellulose phosphate, and cellulose xanthate; hemicelluloses such as xylan, mannan, alabogalactan, and araban; alcohol lignin, dioxane lignin, phenol lignin,
Lignins such as hydrotrovic lignin, mercaptolignin, thioglycolic acid lignin, lignin sulfonic acid, alkali lignin, thioalkali lignin, acid lignin, copper oxide-ammonia lignin, periodate lignin; phenol-formaldehyde resin, partially saponified polyvinyl Examples thereof include alcohol and polyvinyl alcohol.

Examples of the amphoteric polymer compound include glue, gelatin, casein, albumin and the like.

Examples of the anionic polymer compound include sulfomethylated polyacrylamide; polyacrylic acid; alginic acid, acrylamide-vinyl sulfonic acid copolymer, polymethacrylic acid, polystyrene sulfonic acid, polyvinyl sulfonic acid, and alkali metals thereof. Salts or ammonium salts; polymer compounds having a carboxyl group or a sulfonic acid group in the side chain such as carboxymethyl cellulose and the like can be mentioned.

Examples of the cationic polymer compound include polyvinylamine, polyethyleneamine, polyethyleneimine, polyacrylamide, N-vinyl-2-pyrrolidone-acrylamide copolymer, polyvinylpyridine, polyvinylpyrrolidone, polyvinylcarbazole, and the like.
Examples thereof include nitrogen-containing polymer electrolytes such as polyvinyl imidazoline, polydimethylaminoethyl acrylate, and polydimethylaminoethyl methacrylate.

These may be used alone or in combination of two or more.

Among these (D) water-soluble polymer compounds, preferred are carboxymethylcellulose, methylcellulose, polyethyleneimine, polyvinylpyrrolidone, polyvinylalcohol and gelatin, and particularly preferred is polyvinylalcohol. When polyvinyl alcohol is used as the component (D), the scale-inhibiting effect varies depending on the degree of polymerization, and when a polymer having a polymerization degree of 1000 or more is used, a particularly good scale-inhibiting effect is obtained.

The preferred concentration of the component (D) in the coating solution is 0.
It is 0001 to 5% by weight, especially 0.001 to 0.5% by weight. Examples of (E) pH adjusters include sulfuric acid, hydrochloric acid, phosphoric acid, nitric acid, carbonic acid, perchloric acid, molybdic acid, tungstic acid, phosphomolybdic acid, phosphotungstic acid, silicomolybdic acid, silicotungstic acid, Examples include formic acid, acetic acid, oxalic acid, lactic acid, maleic acid, glycolic acid, thioglycolic acid, p-toluenesulfonic acid, tannic acid and phytic acid, and their acid salts.
These can be used alone or in combination of two or more. Particularly preferred among these are phosphoric acid, perchloric acid, molybdic acid, tungstic acid, phosphomolybdic acid, phosphotungstic acid, silicomolybdic acid,
They are silicotungstic acid, p-toluenesulfonic acid, phytic acid, and their acid salts. When adjusting the pH of the coating liquid, it is desirable that these pH adjusting agents be prepared beforehand as an aqueous solution having an appropriate concentration.

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 liquid is applied not only to the inner wall surface of the polymerization vessel but also to other portions with which the monomer comes into contact during the polymerization, thereby forming a coating film. For example, it is better to form a coating film on the stirring blade, stirring shaft, condenser, header, search coil, bolt, nut, etc. by applying the coating liquid.

[0028] More preferably, the coating liquid is a site other than the site where the monomer comes into contact during the polymerization, where polymer scale may adhere, for example, an unreacted monomer recovery system is not recovered. It is better to form a coating film by applying the above-mentioned coating solution on the site where the reactive monomer comes into contact, that is, the inner surface of the equipment and piping of the system. Specific examples of such a portion include inner surfaces of a monomer distillation column, a condenser, a monomer storage tank, a valve, and the like.

The method of applying the coating liquid to the inner wall surface of the polymerization vessel is not particularly limited, and examples thereof include brush coating, spray coating, and a method of withdrawing after filling the polymerization vessel with the coating solution. No. 57-61001, No. 55-3628
No. 8, Special Publication No. 56-501116, No. 56-501117, JP
The automatic coating method described in No. 59-11303 can also be used. Further, the method of drying the wet surface due to the application of the coating solution is not limited, and the following method can be used, for example. That is,
After applying the coating solution, a method of applying an appropriately heated hot air to the coating surface, or heating the inner wall surface of the polymerization vessel and the other surface to which the coating solution is applied, for example, to 30 to 80 ° C in advance and heating It is possible to use a method in which the coating liquid is directly applied to the formed surface. After the coated surface is dried, 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.
The degree is preferably 0.01 to ² g / m ² .

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 a coating film is formed in the polymerization vessel by a conventional method. Polymerize. That is, in addition to a haloethylene-containing monomer and a polymerization initiator (catalyst), if necessary, a polymerization medium such as water, and a dispersant such as a suspending agent, a solid dispersant, a nonionic or anionic emulsifier, and the like. After charging, polymerization is carried out by a conventional method.

The monomer polymerized by the production method of the present invention is
The haloethylene represented by the general formula (I) may be used alone.
A monomer mixture with another monomer having an ethylenic double bond copolymerizable therewith (usually, the haloethylene content of 50
Weight% or more). Examples of the haloethylene represented by the general formula (I) include vinyl halides such as vinyl chloride and vinyl fluoride, and vinylidene halides such as vinylidene chloride and vinylidene fluoride, which may be used alone or in combination of two or more. It can also be used as a monomer mixture. Examples of the other monomer having an ethylenic double bond that can be used as a comonomer include, for example,
Vinyl esters such as vinyl acetate and vinyl propionate;
Acrylic acid, methacrylic acid, and their esters and salts; diene monomers such as butadiene, chloroprene, and isoprene; vinyl aromatic compounds such as styrene and α-methylstyrene; and vinyl ethers. These comonomers can be used alone or in combination of two or more. Further, the form of polymerization to which the method of the present invention is applied is not particularly limited, and is effective in any of the polymerization forms of suspension polymerization, emulsion polymerization, solution polymerization, bulk polymerization and gas phase polymerization, and particularly suspension. It is more suitable for polymerization in an aqueous medium such as polymerization and emulsion polymerization.

A general polymerization method will be specifically described below by taking 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, after exhausting the inside of the polymerization vessel to reduce the pressure to 0.1 to 760 mmHg, the monomer was 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. The reaction temperature during the polymerization depends on the kind of the monomer to be polymerized. For example, in the case of vinyl chloride polymerization, the polymerization is carried out at 30 to 80 ° C. Polymerization has almost no difference between the inlet temperature and the outlet temperature of the cooling water that flows in and out when the internal pressure of the polymerization vessel drops to 0 to 7 kgf / cm ² · G or into the jacket equipped around the polymerization vessel. Is completed (ie, when the heat generated by the polymerization reaction disappears), it is judged to be completed. Water, a dispersant and a polymerization initiator charged during the polymerization are usually 20 to 20 parts of water per 100 parts by weight of the monomer.
500 parts by weight, dispersant 0.01 to 30 parts by weight, polymerization initiator 0.01 to
5 parts by weight.

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. Further, in the case of bulk polymerization, the inside of the polymerization vessel is evacuated to a pressure of about 0.01 to 760 mmHg, and then the monomer and the polymerization initiator are charged into the polymerization vessel and the reaction temperature is adjusted to -10 ° C to 250 ° C. Polymerize. Specific polymerization methods by bulk polymerization include, for example, a liquid bulk polymerization method and a vapor phase polymerization method in the polymerization of vinyl chloride monomer.

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. It is possible to prevent the adhesion of the polymer scale 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-cumylperoxy neodecanoate, cumene hydroper Oxide, cyclohexanone peroxide, t-butyl peroxypivalate, bis (2-ethoxyethyl) peroxy dicarbonate, benzoyl peroxide, lauroyl peroxide, 2,4-dichlorobenzoyl peroxide, diisopropyl peroxydicarbonate,
α, α′-azobisisobutyronitrile, α, α′-azobis-2,4-dimethylvaleronitrile, potassium peroxodisulfate, ammonium peroxodisulfate, p-
Polymerization initiators such as menthane hydroperoxide; partially saponified polyvinyl alcohol, polyacrylic acid, copolymers of vinyl acetate and maleic anhydride, cellulose derivatives such as hydroxypropylmethyl cellulose, and natural or synthetic polymer compounds such as gelatin. Suspending agents; solid dispersants such as calcium phosphate and hydroxyapatite; nonionic emulsifiers such as sorbitan monolaurate, sorbitan trioleate and polyoxyethylene alkyl ethers; sodium alkylbenzenesulfonates such as sodium lauryl sulfate and sodium dodecylbenzenesulfonate; dioctyl. Anionic emulsifiers such as sodium sulfosuccinate; fillers such as calcium carbonate and titanium oxide; tribasic lead sulfate, calcium stearate, dibutyltin dilaurate Stabilizers such as dioctyltin methylcaptide; lubricants such as rice wax, stearic acid and cetyl alcohol; plasticizers such as DOP and DBP; mercaptans such as t-dodecyl mercaptan and chain transfer agents such as trichloroethylene; pH adjusters, etc. Also in the polymerization system, the method of the present invention can effectively prevent the adhesion of polymer scale.

Particularly suitable polymerization when the present invention is applied is, for example, suspension polymerization or emulsion polymerization of vinyl halide such as vinyl chloride or vinylidene halide, or a monomer mixture mainly containing them. Be done. When using the polymer scale anti-adhesion agent of the present invention, the application operation of the coating solution may be appropriately carried out for each batch or several tens of batches of polymerization. Since the formed coating film has high durability and the anti-adhesion action of the polymer scale lasts, it is usually sufficient to carry out the coating treatment once every several batches or tens of batches. The polymerization vessel can be repeatedly used without attaching the polymer scale to the inner wall of the vessel.

[0037]

EXAMPLES The present invention will be described in detail below with reference to examples and comparative examples. In addition, in Tables 3, 4, and 5 described later, the experiment numbers marked with * are comparative examples, and the other experiment numbers are examples of the present invention.

Example 1 Preparation Example of Coating Liquid The component (A) (aromatic compound and / or dye) shown in Tables 1 and 2 is dissolved or dispersed in a solvent, and the degree of polymerization is 1500.
The component (B) consisting of polyvinyl potassium sulphate is added in the form of an aqueous solution.
The component (C) shown in 1) was added and mixed in a state of being a methanol solution to prepare coating liquid Nos. 1 to 45. The concentration of the component (A) in the coating solution was 0.1% by weight. Tables 1 and 2 show the type of component (A) used in each coating solution, the weight ratio of component (A) to component (B), the type of component (C), and the concentration of component (C) in the coating liquid. , And the type of solvent used. However, coating liquid Nos. 20 and 21
Is a comparative example not containing both the component (B) and the component (C).

[0039]

[Table 1]

[0040]

[Table 2]

Example 2 In each experiment, polymerization was carried out as follows using a stainless steel polymerization vessel with an internal volume of 20 l equipped with a stirrer. Experiment No.1
In Nos. 02 to 141, the coating solutions prepared in the examples shown in Tables 3, 4 and 5 were used for the inner wall of the polymerization vessel, the stirring shaft, the stirring blades, the baffles, and other portions where the monomer comes into contact during the polymerization. It was applied to the sample, dried by heating at 50 ° C. for 15 minutes, and washed with water to form a coating film. The coating film formed has a coating amount of 0.1 g / m after drying.
^{Was 2} .

The outline of the coating film in each experiment is as follows. -Experiment No. 101: No coating film is formed. -Experiment Nos. 102 to 120, 125 and 133: The coating liquid prepared in Example 1 was used for coating as it was. -Experiment Nos. 121 to 124, 126 to 132 and 134 to 141: In addition to the coating liquid prepared in Example 1, the component (D) (water-soluble polymer compound) shown in Tables 3, 4 and 5 and optionally
(E) A solution prepared by dissolving or dispersing a pH adjuster was used as a coating liquid. Of these experiments, Nos. 101 to 103 are comparative examples.

Tables 3, 4, and 5 show the No. of the coating solution used in each experiment, the type and concentration of the component (D) used, the type (E) of the pH adjusting agent added, and the coating liquid. Shows the pH of. Next, in the polymerization vessel in which the coating film was formed by the coating treatment as described above, 5.2 kg of vinyl chloride, 10 kg of pure water, 5.2 g of partially saponified polyvinyl alcohol and 2.6 g of bis (2-ethylhexyl) peroxydicarbonate. Was charged and polymerized at 58 ° C. for 6 hours while stirring. After completion of polymerization
The produced polymer and unreacted monomer were recovered, and the inside of the polymerization vessel was washed with water. Then, in the same manner, a total of 3 batches of polymerization are carried out by repeating the above-mentioned operation under the above-mentioned polymerization conditions,
The scale adhesion amount after 3 batches was examined. The results are shown in Table 3, Table 4 and Table 5.

[0044]

[Table 3]

[0045]

[Table 4]

[0046]

[Table 5]

Example 3 In each experiment, the coating solution was applied to a polymerization vessel made of stainless steel with a stirrer and having an internal volume of 20 l by a method similar to that in Example 2, dried,
It was washed with water to form a coating film. The formed coating film had a coating amount after drying of 0.1 g / m ² .

The outline of the coating film formed in each experiment is as follows. -Experiment No. 201: No coating film was formed. -Experiment Nos. 202 to 207: The coating liquid prepared in Example 1 was used for coating as it was. -Experiment Nos. 208 to 225: The coating liquid prepared in Example 1 was further dissolved or dispersed with the component (D) (water-soluble polymer compound) and / or (E) pH adjuster shown in Tables 6 and 7. Was used as a coating liquid. Among these experiments, the experiments of Nos. 201 to 203 are comparative examples. Tables 6 and 7 show N of the coating solution used in each experiment.
o., type of (D) used and its concentration, added (E)
The type of pH adjuster and the pH of the coating liquid are shown.

Next, 12 kg of water, 5.1 kg of vinyl chloride, 1.2 kg of vinyl acetate, 3.6 g of partially saponified polyvinyl alcohol, 1.2 g of hydroxypropylmethyl cellulose, trichloroethylene were placed in the polymerization vessel on which the coating film was formed by the coating treatment as described above. Charge 60 g and 1.5 g of α, α'-azobis-2,4-dimethylvaleronitrile, and stir for 6 at 58 ° C with stirring.
Polymerized for hours. After the polymerization was completed, the produced polymer and the unreacted monomer were recovered, and the inside of the polymerization vessel was washed with water. Thereafter, in the same manner, a total of 3 batches of polymerization were carried out by repeating the above-mentioned operation under the above-mentioned polymerization conditions, and the scale adhesion amount after 3 batches was examined. The results are shown in Tables 6 and 7.

[0050]

[Table 6]

[0051]

[Table 7]

[0052]

According to the present invention, in the polymerization of haloethylene or a monomer mixture containing the haloethylene as an essential component, the composition of the polymerization system, the type of additives such as a polymerization initiator, etc. Adhesion of the polymer scale to the inner wall surface of the polymerization vessel can be effectively prevented. This effect is also effective in any type of polymerization such as suspension polymerization, emulsion polymerization, bulk polymerization, solution polymerization and gas phase polymerization, and is not limited to a glass lined polymerization vessel,
It is also effective when the polymerization is carried out in a stainless steel or other steel polymerization vessel.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Mikio Watanabe No. 1 Towada, Kamisu-cho, Kashima-gun, Ibaraki Prefectural Shin-Etsu Chemical Co., Ltd. Wada No. 1 Shin-Etsu Chemical Co., Ltd.

Claims (5)

[Claims] 1. (A) a primary, secondary or tertiary amino group,
An aromatic compound having at least one group selected from the group consisting of quaternary ammonium groups and azo groups, and / or a dye having at least one group selected from the above group,
And (B) at least one selected from alkali metal salts and ammonium salts of polyvinyl sulfate, represented by the general formula (I): [Here, X represents a halogen atom, and R represents a hydrogen atom or a halogen atom. ] A polymer scale adhesion preventive agent for polymerizing a monomer having an ethylenic double bond, which contains haloethylene as an essential component. 2. The polymer scale anti-adhesion agent according to claim 1, which further comprises (C) a naphthoquinone natural dye. 3. The polymer scale anti-adhesion agent according to claim 1, which is a liquid dissolved or dispersed in a solvent,
(D) A compound containing a water-soluble polymer compound and having a pH adjusted to 7 or less. 4. A method for preventing adhesion of polymer scale during polymerization of a monomer having an ethylenic double bond containing haloethylene represented by the general formula (I) as an essential component in a polymerization vessel. , An aromatic compound having (A) at least one group selected from the group consisting of primary, secondary, and tertiary amino groups, quaternary ammonium groups, and azo groups on the inner wall surface of the polymerization vessel. And / or a dye having at least one group selected from the above group, and (B) a polymerization in which a coating film containing at least one selected from an alkali metal salt and an ammonium salt of polyvinyl sulfate is formed A method for preventing adhesion of a polymer scale, which comprises the step of performing the polymerization in a container. 5. The method according to claim 3, wherein the coating film further contains (C) a naphthoquinone natural dye.