JP3197430B2 - Polymer scale adhesion inhibitor and method for producing polymer using the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polymer scale inhibitor 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 Conventionally, as a polymerization method of a monomer having an ethylenically unsaturated double bond, a suspension polymerization method, an emulsion polymerization method, a solution polymerization method, a gas phase polymerization method, a bulk polymerization method and the like are known. ing. In any of these polymerization methods, adhesion of the polymer scale easily occurs on the inner wall of the polymerization vessel, a stirrer, or the like at a site where the monomer comes into contact.

When the polymer scale adheres, the yield of the polymer, the cooling capacity of the polymerization vessel, etc. decrease, and the polymer scale peels off and mixes into the polymer. The disadvantage is that the quality of the resulting molded article is reduced. In addition, removing the adhered polymer scale not only requires excessive labor and time, but also has a very serious problem in recent years because unreacted monomers are contained in the polymer scale. There is a risk of human injury due to the monomer.

Conventionally, in order to prevent the adhesion of polymer scale to the inner wall of such a polymerization vessel, for example, as is practiced in the suspension polymerization of vinyl chloride, the polarity of amine compounds, quinone compounds, aldehyde compounds, etc. A method of applying a polymer scale adhesion inhibitor composed of an organic compound to the inner wall of a polymerization vessel to form a coating film, and a method of adding those compounds to an aqueous medium in which suspension polymerization is performed are known (Japanese Patent Publication No. Sho 45). -30343 publication).

[0005] However, these methods show an effect of preventing the adhesion of polymer scale when the polymerization is repeated up to about 5 to 6 batches. Inferior). This point has a remarkable effect particularly when a water-soluble catalyst is used in polymerization, and is not industrially satisfactory.

In order to overcome this disadvantage, for example, Japanese Unexamined Patent Publication No.
Japanese Patent Application No. -13689 proposes a method in which a polymer scale adhesion inhibitor containing a condensation product of an aromatic amine compound as an active ingredient is applied to the inner wall of a polymerization vessel or the like. Such a polymer scale adhesion inhibitor is applied to a portion where the monomer contacts, such as the inner wall of a polymerization vessel, and a coating film is formed.
Even if it is repeated about the batch, the polymer scale does not adhere to the liquid phase in the polymerization vessel. Also, when the water-soluble catalyst is used, the adhesion of the polymer scale in the liquid phase is similarly prevented.

[0007]

However, even if a coating film of a polymer scale adhesion inhibitor containing the above-mentioned condensation product of an aromatic amine compound as an active ingredient is formed, it is located in the upper layer in the polymerization vessel. There is a disadvantage that the polymer scale adheres near the interface between the gas phase and the liquid phase. Once the polymer scale adheres to the vicinity of the interface between the gas phase and the liquid phase, the polymer scale attached gradually grows as the polymerization is repeated, and eventually exfoliates and mixes into the polymer. Sometimes. When the polymer scale is mixed into the polymer in this way, when the polymer is processed into a molded product such as a sheet, many fish eyes are generated in the molded product, and the quality of the molded product is significantly reduced. become.

When the polymer obtained by polymerization is formed into a sheet or the like, the obtained molded product 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 resulting molded product is somewhat colored, but this coloring is called initial coloring, and it is desired that the coloring be as small as possible. However, when a coating film of a polymer scale adhesion inhibitor containing the condensation product of the aromatic amine compound as an active ingredient is formed, the coating film may be peeled or dissolved and mixed into the polymer. The whiteness of the molded product may be reduced, that is, the initial coloring property may be deteriorated.

Accordingly, an object of the present invention is to provide a method for polymerizing a monomer having an ethylenically unsaturated double bond, not only in the liquid phase portion in the polymerization vessel but also in the vicinity of the interface between the gas phase and the liquid phase. In addition to being able to effectively prevent the adhesion of the polymer scale, when molded into a sheet or the like, it is possible to produce a polymer from which a molded article having very few fish eyes and good initial coloring properties is obtained. An object of the present invention is to provide a polymer scale adhesion inhibitor that can be used and a method for producing a polymer using the same.

[0010]

In order to achieve the above object, the present invention provides (A) a condensation product having a molecular weight of 400 to 50,000 obtained by condensing a quinone compound;
Disclosed is a polymer scale adhesion inhibitor for polymerization of a monomer having an ethylenically unsaturated double bond, which comprises an aromatic amine compound.

The present invention also relates to a method for producing a polymer by polymerizing a monomer having an ethylenically unsaturated double bond in a polymerization vessel, comprising condensing (A) a quinone compound on the inner wall surface. A solution containing a condensation product having a molecular weight of 400 to 50,000 obtained by the method (A) and an aromatic amine compound (B), and performing the polymerization in a polymerization vessel having a coating film formed by drying. However, the present invention provides a production method in which the adhesion of the polymer scale in the polymerization vessel is prevented.

(A) Component quinone compound The quinone compound includes, for example, the following general formulas (1) and (2)
A benzoquinone compound represented by the following general formula (3)
And naphthoquinone compounds represented by (4).

[0013]

Embedded image

[0014]

Embedded image (In each formula, a plurality of R ^{1 s} may be the same or different;
_{H, -NH 2, -Cl, -Br} , -OH, -NO 2, -COCH 3, -O
CH ₃ , —N (CH ₃ ) ₂ , —COOH, —SO ₃ H, or an alkyl group having 1 to 3 carbon atoms. )

[0015]

Embedded image

[0016]

Embedded image (In each formula, a plurality of R ¹ may be the same or different, are as defined above also may, -H, -Cl, -Br, -OH, or different from the plurality of R ² in the same. - COCH ₃ , -OCH
_3, -CH _3, a -COOH or -SO ₃ H. )

Specific examples of the benzoquinone compounds represented by the general formulas (1) and (2) include o- and p-benzoquinone, hydroxy-p-benzoquinone, chloro-p-benzoquinone, and bromo-p- Benzoquinone, duloquinone, chloranil and the like are exemplified.

The naphthoquinone compounds represented by the general formulas (3) and (4) include, specifically, 6-methyl-1,4-naphthoquinone, 2-methyl-1,4-naphthoquinone, Lawson,
Examples include juglone, plumbagin, α-naphthoquinone, β-naphthoquinone, and the like.

Among the above quinone compounds, preferred are o- and p-benzoquinone, α-naphthoquinone, β-naphthoquinone and Lawson. The quinone compound,
One type may be used alone, or two or more types may be used in combination.

Preparation of Condensation Product of Quinone Compound An essential component of the polymer scale adhesion inhibitor of the present invention.
The component (A) is obtained by condensing the quinone compound and has a molecular weight in the range of 400 to 50000, preferably 6
It is a condensation product ranging from 00 to 20000. If the molecular weight of the condensation product is less than 400, the effect of preventing polymer scale adhesion is low, and if it exceeds 50,000, the solubility of the condensation product in water and organic solvents is reduced, so that a uniform polymer scale adhesion inhibitor is prepared. And the effect of preventing adhesion of the polymer scale is reduced.

The above condensation product is produced, for example, by reacting the above quinone compound in a suitable solvent, usually at 20 to 150 ° C., preferably at 25 to 100 ° C., and the reaction time is usually 2 to 200 hours. The concentration of the quinone compound in the solvent in the reaction is preferably 0.5
-25% by weight, more preferably 1-20% by weight
Range.

In order to accelerate the condensation reaction, the above reaction is preferably carried out in the presence of an alkaline compound. When the reaction is carried out in the presence of the alkaline compound, the reaction is carried out usually at 20 to 150 ° C, preferably at 25 to 100 ° C. The reaction time is usually about 1 to 100 hours, preferably 7 to 70 hours. The amount of the alkaline compound used is 0.01 to 100 per 100 parts by weight of the quinone compound.
The range of parts by weight is preferable, and the range of 0.1 to 40 parts by weight is more preferable. Examples of the alkaline compound include Li
Examples thereof include hydroxides of alkali metals such as OH, NaOH, and KOH.

Further, in the above condensation reaction, an oxidizing agent can be used as required. Examples of the oxidizing agent include elemental or molecular elemental halogens such as iodine, bromine, chlorine, and fluorine; and oxygen acids and oxygen acids of halogens such as iodic acid, periodic acid, potassium periodate, and sodium perchlorate. Salts; for example, inorganic peroxides such as hydrogen peroxide, sodium peroxide, potassium persulfate, and ammonium persulfate; for example, peracetic acid, benzoyl peroxide, cumene hydroperoxide, perbenzoic acid, p-menthane hydroperoxide and the like Organic peroxides; chlorides and sulfates of metals selected from iron and copper, such as, for example, ferrous chloride, ferric chloride, copper sulfate, cuprous chloride; and, for example, α, α'-azo Bisisobutyronitrile,
azo compounds such as α, α′-azobis-2,4-dimethylvaleronitrile; for example, nitrobenzene, o-, m- and p-oxynitrobenzene, o-, m- and p-nitroanisole;
Examples thereof include aromatic nitro compounds such as o-, m- and p-chloronitrobenzene, o-, m- and p-nitrobenzoic acid, and o-, m- and p-nitrobenzenesulfonic acid.

The solvent used in the above condensation reaction includes
For example, organic solvents such as alcohols, ketones and esters are used, and among them, it is preferable to use an organic solvent miscible with water. Examples of the organic solvent having miscibility with water include alcohols such as methanol, ethanol and propanol; ketones such as acetone and methyl ethyl ketone; and esters such as methyl acetate and ethyl acetate. Among them, alcohols are particularly preferable. It is also possible to use a mixed solvent of water and an organic solvent miscible with water.

When a coating solution described below is prepared, a solution containing a condensation product obtained by subjecting the above quinone compound to a condensation reaction can be used as the component (A). Further, the condensation product precipitated by adding cold water to the condensation product-containing liquid may be filtered and dried.

(B) Component As the aromatic amine compound (B), for example, the following general formula:
Compounds represented by (5) to (7) are mentioned.

[0027]

Embedded image (Wherein R ³ is -H, -NH ₂ , -Cl, -OH, -NO ₂ ,-
COCH ₃ ,-OCH ₃ , -N (CH ₃ ) ₂ or 1 to 3 carbon atoms
R ⁴ is -H, -NH ₂ , -OH,-
CH ₃ , —COOH, or —SO ₃ H. )

[0028]

Embedded image (Wherein, two R ^{3 s} may be the same or different and are as described above, and two R ^{4 s} may be the same or different and are as described above.)

[0029]

Embedded image (Wherein, two R ^{3 s} may be the same or different and are as described above, and R ⁴ is also as described above.)

Specific examples of the compound represented by the above general formula (5) include aniline, o-, m- and p-phenylenediamine, o-, m- and p-aminophenol, o-, m -And p-
Chloroaniline, o-, m- and p-nitroaniline, o-, m-
And p-methylaniline, N, N-dimethyl-p-phenylenediamine, 4-chloro-o-phenylenediamine, 4-methoxy-o-phenylenediamine, 2-amino-4-chlorophenol, 2,3-diaminotoluene , 5-nitro-2-aminophenol, 2-nitro-4-aminophenol, 4-nitro-2
-Aminophenols, o-, m- and p-aminosalicylic acid,
o-, m- and p-aminobenzoic acid, 2,4- and 3,5-diaminobenzoic acid, o-, m- and p-aminobenzenesulfonic acid,
Examples thereof include 2,4-diaminobenzenesulfonic acid.

Specific examples of the compound represented by the above general formula (6) include 4-aminodiphenylamine, 2-aminodiphenylamine, 4,4'-diaminodiphenylamine,
4-amino-3'-methoxydiphenylamine, 4-amino-
4'-hydroxydiphenylamine and the like are exemplified.

Specific examples of the compound represented by the general formula (7) include α-naphthylamine, β-naphthylamine, 1,5-diaminonaphthalene, 1-amino-5-hydroxynaphthalene, and 1,8-naphthylamine. Examples thereof include diaminonaphthalene and 2,3-diaminonaphthalene.

Among the aromatic amine compounds (B), preferred are o-, m- and p-aminophenol, aniline, 4-methoxy-o-phenylenediamine, 5-nitro-2-aminophenol, 2-nitrophenol Nitro-4-aminophenol, o-, m- and
p-aminosalicylic acid, p-aminobenzenesulfonic acid, 2,
4-diaminobenzenesulfonic acid, 4-aminodiphenylamine, 2-aminodiphenylamine, 4,4′-diaminodiphenylamine, α-naphthylamine, 1,5-diaminonaphthalene and 1,8-diaminonaphthalene.

The above-mentioned aromatic amine compounds can be used alone or in combination of two or more.

In the polymer scale anti-adhesion agent of the present invention,
The amount of the component (B) is generally in the range of 0.1 to 1000 parts by weight, preferably 1 to 100 parts by weight per 100 parts by weight of the component (A).
It is in the range of 300 parts by weight.

The polymer scale adhesion inhibitor of the present invention containing the above-mentioned components (A) and (B) as essential components, for example, by being formed as a coating film on the inner wall surface of a polymerization vessel, etc.
The purpose is to prevent adhesion of the polymer scale to the inner wall surface of the polymerization vessel. Usually, when the coating film is formed on the inner wall surface of a polymerization vessel, the polymer scale adhesion inhibitor is used in the form of a solution or a dispersion, that is, a coating solution.

Preparation of Coating Solution The above-mentioned coating solution is prepared by adding the above components (A) and (B) to the following solvents and dissolving or dispersing them. May be adjusted.

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

Among the above solvents, preferred are water and a mixed solvent of water and an organic solvent miscible with water.
Among the above-mentioned organic solvents, examples of the organic solvent having miscibility with water include alcohols such as methanol, ethanol and propanol; ketones such as acetone and methyl ethyl ketone; esters such as methyl acetate and ethyl acetate And the like. When using a mixed solvent of water and an organic solvent that is miscible with water, the content of the organic solvent should be such that there is no danger of ignition, explosion, etc., and there is no problem in handling safety such as toxicity. Is preferred, specifically,
Preferably, the organic solvent is at most 50% by weight,
It is preferably at most 30% by weight.

The coating solution is preferably alkaline, and more preferably has a pH in the range of 7.5 to 13.5.
A range of pH 8.0 to 13.0 is preferred. Examples of the alkaline compound used for pH adjustment include LiOH, NaOH, KOH, and Na.
Alkali metal compounds such as ₂ CO ₃ and Na ₂ HPO ₄ ;
Ammonium compounds such as NH ₄ OH; and organic amine compounds such as ethylenediamine, monoethanolamine, diethanolamine, and triethanolamine.

Other Components In order to further improve the effect of preventing the adhesion of polymer scale, the above coating solution contains (C) a water-soluble polymer compound, (D) an inorganic colloid and (E) an alkali metal silicate. It is preferable to add at least one member selected from the group consisting of
These additives (C) to (E) probably interact with condensation products to increase the hydrophilicity of the coated surface ((C) water-soluble polymer compound), It is presumed to have the effect of increasing the adhesion to the inner wall of the polymerization vessel ((D) inorganic colloid and (E) alkali metal silicate).

(C) Water-Soluble Polymer Compound Examples of the water-soluble polymer compound (C) include gelatin,
Nonionic polymer compounds such as casein; anionic polymer compounds such as polyacrylic acid, polystyrenesulfonic acid, carboxymethylcellulose, and alginic acid;
For example, cationic nitrogen-containing polymer compounds such as polyvinylpyrrolidone, chitosan, and polyacrylamide;
Polyvinyl alcohol, hydroxyethyl cellulose,
Examples thereof include hydroxyl group-containing polymer compounds such as hydroxypropyl cellulose and pectin. Preferred among the above-mentioned water-soluble polymer compounds are gelatin, casein, polyacrylic acid, carboxymethylcellulose, polyvinylpyrrolidone and pectin.

The water-soluble polymer compound (C) can be used alone or in combination of two or more. The amount of the component (C) added is usually 1 to 1000 per 100 parts by weight of the component (A).
Parts by weight, preferably from 5 to 200 parts by weight.

(D) Inorganic Colloid The inorganic colloid (D) is a particle colloid produced by a dispersion method using water as a dispersion medium or a condensation method, and the size of the colloid particles is 1 to 500 μm. Specific examples of the inorganic colloid include metal oxide and hydroxide colloids selected from the group consisting of aluminum, thorium, titanium, zirconium, antimony, tin, iron and the like; tungstate, vanadium pentoxide, gold And silver colloid; silver iodide sol; colloids of selenium, sulfur, silica and the like.

Preferred among the above-mentioned inorganic colloids are aluminum, titanium, zirconium, tin and iron oxide and hydroxide colloids, and colloidal silica.

The inorganic colloid (D) can be used alone or in combination of two or more. Component (D) is added in an amount of usually 1 to 1000 parts by weight, preferably 5 to 500 parts by weight, per 100 parts by weight of component (A).

(E) Alkali Metal Silicate Examples of the alkali metal silicate (E) include metasilicates (M ₂ SiO ₃ ) of alkali metals such as lithium, sodium and potassium, and orthosilicates ( M ₄ SiO ₄ ),
Disilicates _{(M 2 Si 2 O 3)} , trisilicate (M ₃ Si ₃ O
₇ ), sesquisilicic acid (M ₄ Si ₃ O ₁₀ ) and the like (where M represents an alkali metal such as lithium, sodium and potassium), and water glass. The alkali metal silicate (E) can be used alone or in combination of two or more. The content of component (E) is the same as component (A)
It is usually 1 to 1000 parts by weight, preferably 5 to 500 parts by weight, per 100 parts by weight.

When the components (D) and (E) are used in combination, the total amount of the components (D) and (E) is 1 to 1000 parts by weight per 100 parts by weight of the component (A). And more preferably 5 to 500 parts by weight.

In order to maximize the effect of preventing polymer scale adhesion, the water-soluble polymer compound (C) and the inorganic colloid should be used.
It is preferably used in combination with (D) or a combination of a water-soluble polymer compound (C) and a silicate (E) of an alkali metal. When used in combination with the component (C) and the component (D), the component (D) is preferably used in an amount of 5 to 3000 parts by weight, more preferably 50 to 1000 parts by weight, per 100 parts by weight of the component (C). It is preferable to use parts. When used in combination with the component (C) and the component (E), it is preferable to use 5 to 3000 parts by weight of the component (E) per 100 parts by weight of the component (C), and more preferably 50 to 10 parts.
It is preferable to use 00 parts by weight.

The total concentration of the component (A) and the component (B) in the coating solution is not particularly limited as long as the total coating amount described below can be obtained, but is usually about 0.01 to 10% by weight, preferably 0 to 10% by weight. .
It is about 1 to 3% by weight. When the components (C) to (E) are added, the total concentration of the components (A) to (E) is preferably about 0.1 to 20% by weight, and more preferably about 0.2 to 6% by weight. Is preferred.

Formation of Coating Film In order 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, After thoroughly drying in the temperature range from room temperature to 100 ° C, wash with water if necessary.

It is preferable that the coating liquid is applied not only to the inner wall surface of the polymerization vessel but also to other parts with which the monomer comes into contact during the polymerization. For example, stirring blades, stirring shafts, baffles,
Examples include a capacitor, a header, a search coil, a bolt, and a nut.

More preferably, even if the coating liquid is other than the part where the monomer comes into contact during the polymerization, the part where the polymer scale may adhere, for example, a device for recovering unreacted monomer and It is better to form the coating film on the inner surface of the pipe. Specifically, the inner surfaces of a monomer distillation column, a condenser, a monomer storage tank, a valve and the like can be mentioned.

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

The method of drying the wet surface by applying the coating liquid is not limited, and for example, the following method can be used. That is, after the application of the coating solution, a method in which warm air of an appropriate temperature is applied to the application surface, or the inner wall surface of the polymerization vessel to which the coating solution is to be applied and other surfaces are previously heated to, for example, 30 to 80 ° C. For example, a method of directly applying a coating solution to the heated surface can be used. After the application surface is dried, the application 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 ,
It is preferably 0.05 to ² g / m ² .

The above coating operation may be carried out for every one to several tens of batches of polymerization. Since the formed coating film has high durability and the action of preventing adhesion of the polymer scale is maintained, it is not always necessary to perform the coating 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 a portion where the monomer comes into contact during polymerization, and the like, followed by a conventional method in the polymerization vessel. Perform polymerization. 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, a suspending agent, a solid dispersant, a nonionic, anionic emulsifier And then polymerization is carried out by a conventional method.

The monomer having an ethylenically unsaturated double bond to be polymerized by applying the method of the present invention includes, for example,
Vinyl halides such as vinyl chloride; vinyl esters such as vinyl acetate and vinyl propionate; acrylic acid, methacrylic acid, and their esters and salts; maleic acid, fumaric acid, and their esters and anhydrides; Diene monomers such as butadiene, chloroprene and isoprene; styrene; acrylonitrile; vinylidene halide; and vinyl ether. These are used alone or in combination of two or more.

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 any polymerization mode of bulk polymerization and gas phase polymerization, and is particularly suitable for polymerization in an aqueous medium such as suspension polymerization and emulsion polymerization.

Hereinafter, a general polymerization method will be specifically described with reference to suspension polymerization and emulsion polymerization as examples. First,
Charge water and dispersant into the polymerization vessel. Next, the inside of the polymerization vessel is evacuated to reduce the pressure to 0.1 to 760 mmHg, and then the monomer is charged. At this time, the internal pressure of the polymerization vessel is usually 0.5 to 30 kgf / cm ² · G. Further, the polymerization initiator is charged before and / or after charging the monomer. Thereafter, polymerization is carried out at a reaction temperature of 30 to 150 ° C. During polymerization, one or more of water, a dispersant, and a polymerization initiator are added as necessary. The reaction temperature during the polymerization differs depending on the type 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, and in the case of styrene, the reaction temperature is 50 to 150 ° C. To carry out polymerization. In the polymerization, the difference between the inlet temperature and the outlet temperature of the cooling water flowing into and out of the jacket provided around the polymerization vessel when the internal pressure of the polymerization vessel was reduced to 0 to 7 kgf / cm ² · G was almost eliminated. At that time (that is, when the heat generated by the polymerization reaction has disappeared), it is determined to be completed. Water, dispersant, and polymerization initiator charged during the polymerization are usually 20 to 500 parts by weight of water, 0.01 part by weight of dispersant per 100 parts by weight of monomer.
To 30 parts by weight, and 0.01 to 5 parts by weight of a polymerization initiator.

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

In the case of bulk polymerization, about 0.01 to
After evacuating to a pressure of 760 mmHg, a monomer and a polymerization initiator are charged into the polymerization vessel, and polymerization is performed at a reaction temperature of -10 to 250 ° C. For example, in the case of vinyl chloride polymerization, 30 to 80 ° C
In the case of styrene polymerization, the reaction is carried out at 50 to 150 ° C.

When polymerization is carried out by applying the method of the present invention, adhesion of the polymer scale can be prevented regardless of the material of the inner wall surface of the polymerization vessel. Needless to say, the adhesion of the polymer scale can be prevented even when the polymerization is carried out in a polymerization vessel made of stainless steel or other steel.

Those added to the polymerization system can be used without any restrictions. That is, for example, t-
Butyl peroxy neodecanoate, bis (2-ethylhexyl) peroxy dicarbonate, 3,5,5-trimethylhexanoyl peroxide, α-cumyl peroxy neodecanoate, cumene hydroperoxide,
Cyclohexanone peroxide, t-butylperoxypivalate, bis (2-ethoxyethyl) peroxydicarbonate, benzoyl peroxide, lauroyl peroxide, 2,4-dichlorobenzoyl peroxide, diisopropylperoxydicarbonate,
polymerization initiators such as α, α′-azobisisobutyronitrile, α, α′-azobis-2,4-dimethylvaleronitrile, potassium peroxodisulfate, ammonium peroxodisulfate, and p-menthane hydroperoxide; Suspending agents such as partially saponified polyvinyl alcohol, polyacrylic acid, copolymers of vinyl acetate and maleic anhydride, cellulose derivatives such as hydroxypropylmethylcellulose, natural and synthetic high molecular compounds such as gelatin; for example, calcium phosphate, hydroxyapatite Nonionic emulsifiers such as sorbitan monolaurate, sorbitan triolate, and polyoxyethylene alkyl ether; and sodium alkyl benzene sulfonate such as sodium lauryl sulfate and sodium dodecylbenzene sulfonate Anionic emulsifiers such as sodium and sodium dioctyl sulfosuccinate; fillers such as calcium carbonate and titanium oxide; stabilizers such as tribasic lead sulfate, calcium stearate, dibutyltin dilaurate, dioctyltin mercaptide; Lubricants such as wax, stearic acid and cetyl alcohol; plasticizers such as DOP and DBP; mercaptans such as t-dodecyl mercaptan; chain transfer agents such as trichloroethylene; The method of the present invention can effectively prevent the adhesion of the polymer scale.

The polymer scale adhesion inhibitor of the present invention may be used for forming a coating film on the inner wall surface of the polymerization vessel and then added directly to the polymerization system, thereby improving the scale prevention effect. It can also be done. In this case, the amount of the polymer scale adhesion inhibitor is suitably about 10 to 1000 ppm based on the total weight of the monomers to be charged. At the time of addition, care is taken so as not to affect the quality of the polymer such as fish eye, bulk specific gravity, particle size distribution and the like.

[0067]

The present invention will be described below in detail with reference to examples and comparative examples. In each of the following tables, an experiment number marked with * is a comparative example, and other experiment numbers are examples of the present invention.

Production Example 1 Production of Condensation Product of Quinone Compound Production of Condensation Product No. 1 A mixed solvent of 450 g of methanol and 450 g of water was added to a 2-liter reactor equipped with a reflux condenser. Subsequently, 100 g of α-naphthoquinone as a quinone compound and 10 g of sodium hydroxide were added. Next, 65
C., the mixture in the reactor was reacted at 65.degree. C. for 10 hours, and then cooled to room temperature. Thus, a solution of the condensation product No. 1 was obtained. The molecular weight of the condensation product No. 1 obtained above was measured by the following method and was found to be 3,000.

Measurement of molecular weight Measured by gel permeation chromatography (GPC). The molecular weight is represented by a number average molecular weight in terms of polystyrene. The measurement conditions are as follows. Column: Guard column Product name shim-pack GPC-800DP, Shimadzu Corporation Analytical column Product name shim-pack GPC-803D, 802D, Shimadzu Corporation Mobile phase: 10 mM LiBr / DMF Flow rate: 1.0 ml / min Detector: RI temperature: 60 ℃

Production of Condensation Product Nos. 2 to 9 In each production, using the solvent, quinone compound and alkaline compound shown in Table 1, the condensation product No. 1 was produced in the same manner as in the production of condensation product No. 1. .2-9 were prepared. In Table 1,
The concentration of the quinone compound in the solution (% by weight), the ratio of the alkaline compound to the quinone compound (% by weight), the reaction temperature and the reaction time are shown. The molecular weight of each condensation product was measured in the same manner as for condensation product No. 1. Table 1 shows the results.

[0071]

[Table 1]

Example 1 (Experiment Nos. 101 to 110) In each experiment, a polymerization vessel made of a stainless steel with a stirrer and having an internal volume of 1000 liters was used as a polymerization vessel. In each experiment,
Conditions shown in Table 3 (solvent composition, condensation product (A) + (B) + (C) +
(D) + (E) total concentration, (A) :( B) :( C) :( D) :( E) weight ratio and p
H), the condensation product (A), the aromatic amine compound (B), the water-soluble polymer compound (C), the inorganic colloid (D) and the alkali metal silicate (E ) And a solvent and an alkaline compound shown in Table 3 to prepare a coating solution. In addition, the inorganic colloid of the component (D) used in this example and Example 2 shown below (a to a in Tables 2 and 6)
g) is as shown in Table 5.

In each experiment, the coating solution prepared as described above was applied to the inner wall of the polymerization vessel, a stirring shaft, a stirring blade, and other portions where the monomer was in contact with the polymerization, and heated and dried at 40 ° C. for 15 minutes. After forming the coating film by heating, the inside of the polymerization vessel was washed with water.

Thereafter, in each experiment, polymerization was carried out as follows. 400 kg of water, 200 kg of vinyl chloride, 250 g of partially saponified polyvinyl alcohol, 25 g of hydroxypropylmethylcellulose, and 70 g of 3,5,5-trimethylhexanoyl peroxide were placed in a polymerization vessel in which a coating film was formed as described above. The polymerization was conducted at 66 ° C. for 6 hours while charging and stirring. After completion of the polymerization, 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 same operation was repeated as the number of batches shown in Table 4 except that the above-mentioned operation of the polymerization and the washing with water in the polymerization vessel was regarded as one batch without performing the coating operation. For each experiment,
After the end of the final batch, the amount of polymer scale deposited in the liquid phase portion in the polymerization vessel and the amount of polymer scale deposited near the interface between the gas phase and the liquid phase were measured by the following methods. Table 4 shows the results. Measurement of Attached Amount of Polymer Scale The scale attached to a predetermined area of 10 × 10 cm on the inner wall of the polymerization vessel was scraped off with a stainless steel spatula as completely as possible with the naked eye, and weighed with a balance. The weighed value was multiplied by 100 to determine the amount of scale adhering per 1 m ² .

Further, the number of fish eyes when the polymer obtained in each experiment was formed into a sheet was measured by the following method. Table 4 shows the results. Measurement of fish eye 100 parts by weight of the obtained polymer, dioctyl phthalate (DO
P) A mixture prepared by mixing 50 parts by weight, 1 part by weight of dibutyltin dilaurate, 1 part by weight of cetyl alcohol, 0.25 part by weight of titanium oxide, and 0.05 part by weight of carbon black 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 per 100 cm ^{2 of the} obtained sheet was examined by a light transmission method.

Further, in order to evaluate the initial coloring property when the polymer obtained in each experiment was formed into a sheet, a lightness index was used.
(L value) was measured by the following method. Table 4 shows the results. Measurement of lightness index (L value) 100 parts by weight of obtained polymer, 1 part by weight of tin laurate-based stabilizer (TS-101, manufactured by Akishima Chemical Co., Ltd.), and cadmium-based stabilizer (C-Catalyst, C- 100J) 0.5 parts by weight and 50 parts by weight of dioctyl phthalate as a plasticizer are kneaded at 160 ° C. for 5 minutes using a two-roll mill, and then a sheet having a thickness of 1 mm is formed. Next, the molded sheet is placed in a 4 × 4 × 1.5 cm formwork, heated at 160 ° C. and 65 to 70 kgf / cm ² for 0.2 hours, and pressure molded to prepare a measurement sample. About this sample, JIS
The lightness index L in the color difference formula of Hunter described in Z 8730 (1980) was determined, and the larger the L value, the higher the whiteness, that is, the better the initial coloring property. The L value is obtained as follows. According to the description of JIS Z 8722, standard light C, photoelectric colorimeter (Z-1001DP colorimeter, manufactured by Nippon Denshoku Industries Co., Ltd.)
And the stimulus value Y in the XYZ color system
Ask for. The geometric conditions for illumination and light reception are JIS
The condition d described in section 4.3.1 of Z 8722 was adopted. From the obtained stimulus value Y, the equation described in JIS Z 8730 (1980): L = 10
The L value is calculated from Y ^1/2 .

[0078]

[Table 2]

[0079]

[Table 3]

[0080]

[Table 4]

[0081]

[Table 5]

Example 2 (Experiments Nos. 201 to 210) In each experiment, a stainless steel polymerization vessel equipped with a stirrer and having a capacity of 20 liters was used as the polymerization vessel. In each experiment,
Conditions shown in Table 7 (solvent composition, condensation product (A) + (B) + (C) +
(D) + (E) total concentration, (A) :( B) :( C) :( D) :( E) weight ratio and p
H), the condensation product (A), aromatic amine compound (B), water-soluble polymer compound (C), inorganic colloid (D) and alkali metal silicate (E) shown in Table 6 ), And
A coating solution was prepared using the solvent and the alkaline compound shown in Table 7. These coating solutions are applied to the inner wall of the polymerization vessel and the stirring shaft,
Apply to the parts where the monomer contacts during the polymerization, such as stirring blades,
After heating and drying at 40 ° C. for 15 minutes to form a coating film, the inside of the polymerization vessel was washed with water.

Next, in each experiment, polymerization was carried out as follows. 9 kg of water, 225 g of sodium dodecylbenzenesulfonate, 12 g of t-dodecylmercaptan and 13 g of potassium peroxodisulfate were charged into a polymerization vessel having a coating film formed by the above-mentioned coating treatment, and nitrogen gas was passed through the polymerization vessel. After replacement, 1.3 kg of styrene and 3.8 kg of butadiene
kg was charged and polymerized at 50 ° C. for 20 hours. After completion of the polymerization, 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 same operation was repeated as the number of batches shown in Table 8 except that the above-mentioned operation of the polymerization and the washing with water in the polymerization vessel was regarded as one batch without performing the coating operation. For each experiment,
After completion of the final batch, the amount of polymer scale deposited in the liquid phase portion in the polymerization vessel and the amount of polymer scale deposited near the interface between the gas phase and the liquid phase were measured in the same manner as in Example 1. Table 8 shows the results. Further, in order to evaluate the initial coloring property when the polymer obtained in each experiment was formed into a sheet, a lightness index (L) was used.
Value) was measured by the following method. Table 8 shows the results.

Measurement of lightness index (L value) To 1 kg of the obtained polymer latex, 1 kg of a 2% magnesium sulfate solution was added, and coagulated and precipitated, followed by filtering off the precipitate. The precipitate separated by filtration was washed with hot water at 80 to 90 ° C. two to three times, and then dried at 40 ° C. for 25 hours using a vacuum dryer to obtain a resin. The obtained resin was placed in a mold having a size of 9 × 9 cm and a depth of 0.1 cm, heated at 195 ° C. and 50 to 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. Produced.
The brightness index L of this sample was determined in the same manner as in Example 1.

[0086]

[Table 6]

[0087]

[Table 7]

[0088]

[Table 8]

Example 3 As a polymerization vessel, a stainless steel polymerization vessel with an internal volume of 20 liters and equipped with a stirrer was used. The coating solution used in Experiment No. 201 of Example 2 was applied to the inner wall of the polymerization vessel, a stirring shaft, a stirring blade, and other parts where the monomer was in contact during polymerization, and heated and dried at 50 ° C. for 15 minutes to form a coating film. After the formation, the inside of the polymerization vessel was washed with water.

Thereafter, 4.0 kg of water and 6 g of sodium dodecylbenzenesulfonate were charged into the polymerization vessel on which the coating treatment was performed, and the temperature was raised to 60 ° C. with stirring. Next, after replacing the gas phase in the polymerization vessel with nitrogen gas,
94 g of n-butyl acrylate, 220 g of methyl methacrylate, 5 g of acrylic acid and 5 g of methacrylic acid were charged, followed by 1 g of ammonium persulfate and 1 g of sodium hydrosulfite, followed by stirring at 60 ° C. for 20 minutes. Further, the mixed monomer (2.1 kg of n-butyl acrylate, methyl methacrylate)
4.8 kg, 100 g of acrylic acid and 100 g of methacrylic acid), 500 g of 1% by weight aqueous solution of ammonium persulfate,
500% by weight aqueous sodium hydrosulfite solution and 25% by weight
Polyoxyethylene nonyl phenyl ether aqueous solution 2.0k
g was added over 3 hours. After the addition was completed, the temperature of the polymerization vessel was raised to 70 ° C., and polymerization was performed for 2 hours. After completion of the polymerization, 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 operations from the formation of the coating film as described above, through the polymerization to the washing in the polymerization vessel, are defined as one batch.
Ninety batches were repeated, and the amount of polymer scale deposited on the liquid phase portion in the polymerization vessel and the amount of polymer scale deposited near the interface between the gas phase and the liquid phase were determined in the same manner as in Example 1. As a result, the attached amount of polymer scale in the liquid phase was 0 g / m ² , and the attached amount of polymer scale near the interface between the gas phase and the liquid phase was 15 g / m ² .

[0092]

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

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-5-112603 (JP, A) JP-A-5-59105 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) C08F 2/00

Claims (3)

(57) [Claims] 1. A monomer having an ethylenically unsaturated double bond, comprising: (A) a condensation product having a molecular weight of 400 to 50,000 obtained by condensing a quinone compound; and (B) an aromatic amine compound. Polymer scale adhesion inhibitor for polymerizing the body. 2. The polymer scale adhesion inhibitor according to claim 1, further comprising: (C) a water-soluble polymer compound, (D) an inorganic colloid, and (E) an alkali metal silicate. Those containing at least one member selected from the group. 3. A method for producing a polymer by polymerization of a monomer having an ethylenically unsaturated double bond in a polymerization vessel, wherein a molecular weight obtained by condensing (A) a quinone compound on the inner wall surface.
A step of applying a liquid containing a condensation product of 400 to 50000 and (B) an aromatic amine compound, and performing the polymerization in a polymerization vessel having a coating film formed by drying. A production method in which adhesion of a polymer scale in a polymerization vessel is prevented.