JPH06145206A - Agent for preventing adhesion of polymer scale, polymerizer for preventing adhesion of polymer scale and method for producing polymer with the same - Google Patents

Abstract

(57) [Summary] [Structure] (A) (A-1) Condensation product of hydroxyl group-containing diphenylpropane compound and (A-2) aldehyde compound, (B) inorganic colloid and (C) highly water-soluble A polymer scale anti-adhesion agent comprising an alkaline solution containing a molecular compound. Apply the polymer scale adhesion preventive agent to the inner wall surface,
A polymerization vessel in which a coating film is formed by drying, and a method for producing a polymer using the polymerization vessel. [Effect] Since it is possible to effectively prevent the adhesion of the polymer scale 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, the present invention is applied to carry out polymerization. If so, the polymer scale removal operation need not be performed for each polymerization, thereby improving productivity.
Moreover, when the obtained polymer is molded into a sheet or the like, a molded product having very few fish eyes and good initial colorability can be obtained.

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, the polymer scale is likely to adhere to the inner wall of the polymerization vessel, the agitator, and the like where the monomer contacts.

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, although these methods show a polymer scale adhesion preventing effect when repeating polymerization up to about 5 to 6 batches, when the number of polymerization batches is larger than that, the preventing effect is lost (inferior in sustainability). There is a disadvantage. 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, for example, a condensation product of an aromatic amine compound and an aromatic nitro compound (Japanese Patent Publication No. 60-30681), a reaction product of a phenolic compound and an aromatic aldehyde (special (JP-A-57-192414), reaction products of polyhydric phenols and aliphatic aldehydes (JP-A-57-502169), reaction products of 1-naphthol and formaldehyde (JP-B-01-31523). ) And the like are known as polymer scale adhesion inhibitors. When a coating film is formed by applying these known polymer scale anti-adhesion agents to the area where the monomer contacts such as the inner wall surface of the polymerization vessel, even if the polymerization is repeated about 100 to 200 batches, the liquid phase in the polymerization vessel is No polymer scale adhesion to the part occurs. Also, when a water-soluble catalyst is used, polymer scale adhesion in the liquid phase part is also prevented.

[0006]

However, a coating film of a conventionally known polymer scale anti-adhesive agent containing the condensation product of the above-mentioned aromatic amine compound and aromatic nitro compound as an active ingredient is formed. 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. When the polymer scale is mixed with the polymer in this way, when the polymer is processed into a molded article such as a sheet,
Many fish eyes are generated in the molded product, and the quality of the molded product is significantly deteriorated.

When the polymer obtained by polymerization is molded into a sheet or the like, the molded product 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 of the above-mentioned conventionally known polymer scale anti-adhesive agent may be peeled off or dissolved and mixed into the polymer, the whiteness of the molded product is lowered, that is, the initial colorability is deteriorated.

The object of the present invention is effective not only when polymerizing a monomer having an ethylenic 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 portion and the liquid phase portion. 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 a condensation product of (A) (A-1) a hydroxyl group-containing diphenylpropane compound and (A-2) an aldehyde compound. Provided is a polymer scale anti-adhesion agent for polymerization of a monomer having an ethylenic double bond, which comprises an alkaline solution containing (B) an inorganic colloid and (C) a water-soluble polymer compound.

The present invention is also a polymerization vessel for polymerizing a monomer having an ethylenic double bond, wherein (A) (A-1) a hydroxyl group-containing diphenylpropane compound and (A) -2) To provide a polymerization vessel having a coating film formed by applying an alkaline solution containing a condensation product with an aldehyde compound, (B) an inorganic colloid, and (C) a water-soluble polymer compound and drying the solution. . 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) (A-1) hydroxyl group-containing diphenylpropane compound is provided on the inner wall surface. And (A-2) a condensation product of an aldehyde compound, (B) an inorganic colloid, and (C) an aqueous solution containing a water-soluble polymer compound are applied and dried to form a film having a coating film. There is provided a manufacturing method which includes a step of performing the polymerization in a vessel, whereby the adhesion of polymer scale in the polymerization vessel is prevented. Hereinafter, the present invention will be described in detail.

(A) Production of Condensation Product (A-1) Diphenylpropane Compound Containing Hydroxyl Group Diphenylpropane Compound Containing Hydroxyl Group (A-1)
Is a compound represented by the following general formula (1).

[Chemical 1] (In the formula, i is an integer of 1 to 5 and j is an integer of 1 to 5.) Specifically, 2,2-bis (2,3-dihydroxyphenyl) propane, 2,2-bis (2,4-dihydroxyphenyl) propane, 2,2-bis (2,3,4-trihydroxyphenyl) propane, 2,2-bis (2,4,6-trihydroxyphenyl) propane, etc. are exemplified. .

(A-2) Aldehyde Compound The aldehyde compound (A-2) is an organic compound having at least one aldehyde group (—CHO group), preferably 1 to 2. The aldehyde compound is, for example, a compound represented by the following general formulas (2) to (4). R ¹ -CHO (2) (In the formula, R ¹ is a group represented by -H, -COOH, -CHO or a substituted or unsubstituted alkyl group having 1 to 5 carbon atoms.) Specifically, , Formaldehyde, acetaldehyde, glyoxylic acid, glyoxal and the like.

[0013]

[Chemical 2] (In the formula, when a plurality of R ^2's are present, they may be the same or different and each is a group represented by —H or —0H, and m is an integer of 1 to 6.) , Benzaldehyde, salicylaldehyde,
Examples include phthalaldehyde.

[Chemical 3] (In the formula, n is an integer of 1 to 4.) Specific examples include heterocyclic aldehydes such as furfural. Preferred among these are formaldehyde, glyoxylic acid, benzaldehyde, salicylaldehyde, and furfural. The aldehyde compounds (A-2) are used alone or in combination of two or more.

Production of Condensation Product (A) The condensation product (A) is obtained by condensing the diphenylpropane compound (A-1) and the aldehyde compound (A-2). The condensation of the diphenylpropane compound (A-1) and the aldehyde compound (A-2) is usually performed in water in the presence of a catalyst at 50 to 50%.
1 to 20 hours at 150 ° C, preferably 2 to 12 at 60 to 110 ° C
It is carried out by reacting for a time. Examples of the catalyst include acid catalysts such as phosphoric acid, sulfuric acid and hydrochloric acid, and NaO.
Base catalysts such as H, KOH, LiOH and NH ₃ can be mentioned.

The ratio of the diphenylpropane compound (A-1) and the aldehyde compound (A-2) used for the production of the condensation product (A) is such that the diphenylpropane compound (A-1) and the aldehyde compound (A- 2) and type of catalyst, composition, reaction temperature,
Diphenylpropane compound, which is affected by reaction time, etc.
(A-1) The aldehyde compound (A-2) is used in an amount of 0.1 to 10 per mol.
It is preferably in a molar amount, more preferably 0.3 to 3 mol. If the amount of the aldehyde compound (A-2) component is too large or too small, the polymer scale adhesion preventing effect will be reduced. The amount of the catalyst used is not particularly limited, but is usually 0.1 to 10 per 1 mol of the diphenylpropane compound (A-1).
Molar, preferably 0.5 to 5 mol.

(B) Inorganic Colloid Inorganic colloid (B) is a particle colloid obtained by dispersing or condensing water as a dispersion medium, and the size of the colloid particles is 1 to 500 mμ. As the inorganic colloid, specifically, aluminum, thorium, titanium,
Colloids of oxides or hydroxides of metals such as zirconium, antimony, tin, iron, tungstic acid, vanadium pentoxide, colloids of gold and silver, silver iodide sol, selenium,
Examples thereof include colloids such as sulfur and silica. Preferred among these are colloids of oxides or hydroxides of aluminum, titanium, zirconium, tin and iron, and silica colloids. The above inorganic colloid (C)
Can be used alone or in combination of two or more.

(C) Water-soluble polymer compound As the water-soluble polymer compound (C), for example, gelatin,
Amphoteric polymer compounds such as casein, polyacrylic acid, polystyrene sulfonic acid, carboxymethyl cellulose, anionic polymer compounds such as alginic acid, polyvinylpyrrolidone, chitosan, cationic nitrogen-containing polymer compounds such as polyacrylamide, polyvinyl alcohol, hydroxyethyl cellulose , Hydroxypropyl cellulose,
Examples thereof include hydroxyl group-containing polymer compounds such as pectin. Among the above water-soluble polymer compounds (C), preferred are gelatin, casein, polyacrylic acid, carboxymethylcellulose, polyvinylpyrrolidone and pectin. The water-soluble polymer compound (C) may be used alone or in combination of two or more.

Preparation of Polymer Scale Anti-Adhesive Agent The polymer scale anti-adhesive agent of the present invention comprises the condensation product (A), inorganic colloid (B) and water-soluble polymer compound described above.
It consists of an alkaline solution containing (C). The polymer scale adhesion preventive agent is applied to the inner wall surface of the polymerization vessel or the like, and dried to form a coating film, whereby the polymer scale adhesion to the inner wall of the polymerization vessel or the like can be prevented.

The polymer scale anti-adhesive agent was obtained, for example, by adding an aqueous medium to the above condensation product (A), inorganic colloid (B) and water-soluble polymer (C) and mixing them. It is prepared by adjusting the pH of the mixed solution to be alkaline.

When the condensation product (A) used for the preparation of the polymer scale anti-adhesion agent is produced by using a base catalyst, the condensation product (A) after completion of the condensation reaction is included. Since the condensation reaction liquid is alkaline, the reaction liquid can be used as it is for the preparation of the polymer scale deposition inhibitor. On the other hand, when the condensation product (A) is produced using an acid catalyst, the solvent of the obtained condensation reaction solution is removed, the condensation product (A) is washed, and the pressure is reduced at a low temperature. The dried product is used for preparing a polymer scale anti-adhesion agent.

Water is usually used as the aqueous medium for preparing the polymer scale anti-adhesion agent, but a mixed solvent of water and an organic solvent miscible with water can also be used. The mixed solvent is a mixed solvent mainly composed of water, and the content of the organic solvent in the mixed solvent is low in the risk of ignition, explosion, etc.,
The amount which does not cause a safety problem in handling such as toxicity is preferably 50% by weight or less, more preferably 30% by weight or less. Examples of the organic solvent miscible with water include alcohols such as methanol, ethanol and propanol, ketones such as acetone and methyl ethyl ketone, and esters such as methyl acetate. The polymer scale anti-adhesion agent is alkaline, preferably having a pH of 9 to 14, and more preferably pH.
11 to 13. Further, examples of the alkaline compound used for adjusting the pH include NaOH, KOH, LiOH, NH _{3 and the} like.

The content ratio of the component (B) in the polymer scale adhesion preventive agent is usually 0.1 to 10 per 100 parts by weight of the component (A).
The amount is 00 parts by weight, preferably 1 to 600 parts by weight. Further, the content ratio of the component (C) is usually 0.1 to 1000 parts by weight, preferably 1 to 300 parts by weight, per 100 parts by weight of the component (A).
Parts by weight. If the amount of the component (B) and / or the component (C) is too large or too small as compared with the amount of the component (A), the effect of preventing adhesion of polymer scale may not be obtained. The total concentration of the component (A), the component (B) and the component (C) in the polymer scale anti-adhesion agent is not particularly limited as long as the total coating amount described below can be obtained, but it is usually about 0.005 to 10% by weight. , Preferably 0.03 to 2.0% by weight.

Formation of Coating Film To form a coating film on the inner wall surface of the polymerization vessel using the polymer scale adhesion preventing agent prepared as described above, first, the polymer scale adhesion prevention agent is added to the inner wall surface of the polymerization vessel. Then, after being sufficiently dried in a temperature range from room temperature to 100 ° C., it is further washed with water if necessary.

The polymer scale anti-adhesion agent is
It is preferable to apply 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, a stirring blade,
Examples include stirring shafts, baffles, condensers, headers, search coils, bolts and nuts. More preferably,
The polymer scale anti-adhesive agent is a site other than the site where the monomer contacts during the polymerization, but the site where the polymer scale may adhere, for example, the inner surface of the equipment and piping of the recovery system of the unreacted monomer. For example, it is better to form the coating film. Specific examples include inner surfaces of a monomer distillation column, a condenser, a monomer storage tank, a valve, and the like.

In this way, when a coating film is formed on the site where the monomer contacts during the polymerization and the site where the other polymer scale may adhere, the adherence of the polymer scale to those sites is formed. Is prevented. The method for applying the polymer scale anti-adhesion agent 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 a coating solution. No. 57-61001, No. 55-36288, Special Publication No. 56-
The automatic coating methods described in JP-A-501116, JP-A-56-501117 and JP-A-59-11303 can also be used.

There is no limitation on the method for drying the wet surface due to the application of the polymer scale anti-adhesive agent. For example, the following method can be used. That is, after the application of the polymer scale anti-adhesive agent, a method of applying an appropriately heated hot air to the application surface, or the inner wall surface of the polymerization vessel and the other surface to which the polymer scale anti-adhesion agent is applied are preliminarily set to, for example, 30 It is possible to use a method in which the polymer scale adhesion preventive agent is directly applied to the heated surface by heating to -80 ° C. 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 g / m ² or more, particularly 0.05 to ²
It is preferably g / m ² . The coating operation described above does not necessarily have to be performed for each batch of polymerization, because the formed coating film has high durability and the polymer scale adhesion preventing action continues. Therefore, the productivity of the product polymer is improved.

The polymer scale adhesion preventive agent of the present invention can also be added to the polymerization medium. In that case, for example, a polymer scale adhesion inhibitor may be used in the coating treatment, and then the inhibitor may be added in a small amount to the polymerization medium. In this case, the scale prevention effect is improved as compared with the case where only the coating process is performed. When such a polymer scale anti-adhesion agent in a solution state is added to the polymerization medium, the addition amount is in the range of 5 to 1000 ppm based on the total weight of the charged monomers having an ethylenic double bond. It should be done.

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. 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 halides such as vinyl chloride; vinyl esters such as vinyl acetate and vinyl propionate; acrylic acid. , Methacrylic acid, and their esters or salts; maleic acid, fumaric acid, and their esters or anhydrides; diene-based monomers such as butadiene, chloroprene, isoprene; styrene, acrylonitrile, vinylidene halide, vinyl ether, etc. To be

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.

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, 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
When it falls to kgf / 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 as a polymerization medium instead of water. A dispersant is used as needed. Other polymerization conditions are generally the same as those for suspension polymerization and emulsion polymerization.

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

When polymerization is carried out by applying the polymer scale adhesion preventing method of the present invention, it is possible to prevent the adhesion of polymer scale regardless of the material of the inner wall surface of the polymerization vessel. The adhesion of polymer scale can be prevented even when the polymerization is carried out in a steel or other steel-made polymerization vessel, a glass-lined polymerization vessel, or the like.

What is added to the polymerization system can be used without any restrictions. That is, for example, t-butyl peroxy neodecanoate, bis (2-ethylhexyl) peroxydicarbonate, 3,5,5-trimethylhexanoyl peroxide, α-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,
Polymerization initiators such as α'-azobisisobutyronitrile, α, α'-azobis-2,4-dimethylvaleronitrile, potassium peroxodisulfate, ammonium peroxodisulfate and p-menthane hydroperoxide; partially saponified polyvinyl alcohol Suspension agents such as polyacrylic acid, copolymers of vinyl acetate and maleic anhydride, cellulose derivatives such as hydroxypropylmethyl cellulose, natural or synthetic polymer compounds such as pyrogallol-acetone resin, and the like;
Solid dispersants such as calcium phosphate and hydroxyapatite; nonionic emulsifiers such as sorbitan monolaurate, sorbitan trioleate and polyoxyethylene alkyl ether; sodium alkylbenzenesulfonates such as sodium lauryl sulfate and sodium dodecylbenzenesulfonate; sodium dioctylsulfosuccinate. Anionic emulsifiers such as; Fillers such as calcium carbonate, titanium oxide; Stabilizers such as tribasic lead sulfate, calcium stearate, dibutyltin dilaurate, dioctyltin methylcaptide; Lubricants such as rice wax, stearic acid, cetyl alcohol; DOP , 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 is present, the method of the present invention Adhesion of polymer scale can be effectively prevented.

[0037]

EXAMPLES The present invention will be described in detail below with reference to examples and comparative examples. In addition, in each of the following tables, the experiment numbers marked with * are comparative examples, and the other experiment numbers are examples of the present invention. Production of condensation product No. 1 A 2-liter three-neck separable flask equipped with a reflux condenser, a thermometer, and a stirrer was charged with water (1 liter) and diphenylpropane compound (A-1) as 2,2-bis. (2,3,4-Trihydroxyphenyl) propane (1 mol), formaldehyde (1.2 mol) as the aldehyde compound (A-2), and phosphoric acid (1 mol) as the catalyst were added. While the flask was heated to 85 ° C. in an oil bath, the reaction mixture in the flask was stirred under a nitrogen stream for 5 hours to carry out a reaction, and then cooled. Next, the solvent of the cooled reaction mixture was removed, the residue was washed, and dried under reduced pressure at 50 ° C. Thus, condensation product No. 1 was obtained.

Production of Condensation Products Nos. 2 to 7 In each production, water was used as a solvent, 2,2-bis (2,3,4-trihydroxyphenyl) propane was used as the diphenylpropane compound (A-1), and Aldehyde compound shown in 1
(A-2), using the catalyst and solvent, the conditions ((A
-1) + (A-2) + catalyst total concentration, (A-1) :( A-2): catalyst ratio, reaction temperature and reaction time) under the same production operation as condensation product No. 1 I went. Thus, condensation products Nos. 2 to 7 were obtained.

[0039]

[Table 1]

Example 1 (Experiment Nos. 101 to 110) Polymerization was carried out in the following manner using a stainless steel polymerization vessel equipped with a stirrer and having an internal volume of 2000 liters. In each experiment, the condensation product (A) shown in Table 2 was used under the conditions shown in Table 2 (solvent composition, total concentration, (A) :( B) :( C) ratio and pH).
A polymer scale adhesion preventive agent was prepared using the inorganic colloid (B), the water-soluble polymer compound (C), the solvent and the alkaline compound. The inorganic colloids used in Example 1 and Example 2 below are as shown in Table 4. In each experiment, the prepared polymer scale anti-adhesion agent was applied to the inner wall of the polymerization vessel, the stirring shaft, the stirring blade and other portions where the monomer contacts during the polymerization, and heated at 50 ° C for 15 minutes and dried to form a coating film. After forming, it was washed with water.

Then, in each experiment, 800 kg of water, 400 kg of vinyl chloride, and 500 parts of partially saponified polyvinyl alcohol were placed in the polymerization vessel where the coating film was formed by the coating treatment as described above.
g, hydroxypropyl methylcellulose 50 g and 3,5,
140 g of 5-trimethylhexanoyl peroxide was charged and polymerized at 66 ° 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 to remove the residual resin.

The operation from the formation of the coating film through the polymerization to the washing of the inner wall of the polymerization vessel as described above is regarded as one batch, and the same operation is repeated for the number of batches shown in Table 3, and after the final batch is completed, the liquid in the polymerization vessel is finished. The amount of polymer scale attached to the phase portion and the amount of polymer scale attached near 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 3. -Measurement of amount of adhered polymer scale: A scale was scraped off with a spatula, and the scale adhered to a 10 x 10 cm area on the inner wall of the polymerization vessel was weighed. The measured value was multiplied by 100 to obtain the scale adhesion amount per 1 m ² .

In addition, the fish eye when the polymer obtained in each experiment was molded into a sheet was measured by the following method. The results are shown in Table 3.・Fish eye measurement 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 in 100 cm ^{2 of the} obtained sheet was examined by a light transmission method.

Further, in order to evaluate the initial colorability when the polymer obtained in each experiment was molded into a sheet, a lightness index was used.
(L value) was measured by the following method. The results are shown in Table 3. -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 × 1.5 cm, heat at 160 ° C and 65-70 kgf / cm ² and press-mold 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. The L value is obtained as follows. Standard light C, photoelectric colorimeter (Nippon Denshoku Industries Co., Ltd., Z-1001DP) as described in JIS Z 8722
Type colorimetric color difference meter) to obtain the stimulus value Y of the XYZ color system by the direct reading method of the stimulus value. 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, the L value is calculated according to the formula: L = 10Y ^1/2 described in JIS Z 8730 (1980).

[0045]

[Table 2]

[0046]

[Table 3]

[0047]

[Table 4]

Example 2 (Experiment Nos. 201 to 207) 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, Table 5
Conditions (solvent composition, (A) + (B) + (C) total concentration, (A):
(B) :( C) ratio and pH) so that the condensation product (A), inorganic colloid (B) and water-soluble polymer compound (C) shown in Table 5
A polymer scale anti-adhesion agent was prepared using a solvent and an alkaline compound. These polymer scale anti-adhesion agents are applied to the inner wall of the polymerization vessel, the stirring shaft, the stirring blade and other parts where the monomers come into contact with each other during polymerization, heated at 50 ° C for 15 minutes and dried to form a coating film, and then washed with water did.

Next, in each experiment, 9 kg of water, 225 g of sodium dodecylbenzenesulfonate, 12 g of t-dodecyl mercaptan and 13 g of potassium peroxodisulfate were placed in a polymerization vessel in which a coating film was formed by applying the coating 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. The operation from the formation of the coating film to the washing in the polymerization vessel through the polymerization as described above is defined as one batch, and the same operation is repeated for the number of batches shown in Table 6, and after the end of the final batch, The polymer scale deposition amount and the polymer scale deposition amount in the vicinity of the interface between the gas phase portion and the liquid phase portion were determined in the same manner as in Example 1 for each experiment. The results are shown in Table 6.

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 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 and heated at 195 ° C. and 50-60 kgf / cm ² to a final pressure of 80 kgf.
A sample for measurement was prepared by pressure molding at / cm ² . The lightness index L of this sample was determined in the same manner as in Example 1.

[0051]

[Table 5]

[0052]

[Table 6]

[0053]

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 polymerization is carried out by applying the present invention, it is not necessary to carry out the work of removing the polymer scale each time the polymerization is carried out, thereby improving the productivity. Further, according to the present invention, since the coating liquid used for forming the coating film contains water as a main component, there is little risk of ignition, explosion, etc. of the organic solvent, and the range is such that toxicity is not a problem. can do. Furthermore, when the polymer obtained by applying the present invention to perform polymerization 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 colorability, and specifically, when the lightness index (L value) in the Hunter color difference formula described in JIS Z 8730 (1980) is, for example, a vinyl chloride polymer. Is 70 or more, and in the case of SBR, 80 or more.

Claims (3)

[Claims] 1. A condensation product of (A) (A-1) a hydroxyl group-containing diphenylpropane compound and (A-2) an aldehyde compound, (B) an inorganic colloid, and (C) a water-soluble polymer compound. A polymer scale anti-adhesion agent for polymerization of a monomer having an ethylenic double bond, which comprises an alkaline solution containing the agent. 2. A polymerization vessel for polymerizing a monomer having an ethylenic double bond, wherein (A) (A-1) a hydroxyl group-containing diphenylpropane compound and (A-2) an aldehyde are provided on the inner wall surface. A polymerization vessel having a coating film formed by coating an alkaline solution containing a condensation product with a compound, (B) an inorganic colloid, and (C) a water-soluble polymer compound, and drying the solution. 3. A method for producing a polymer by polymerizing a monomer having an ethylenic double bond in a polymerization vessel, wherein (A) (A-1) a hydroxyl group-containing diphenylpropane compound is provided on the inner wall surface. , (A-2) Condensation product with aldehyde compound, (B) Inorganic colloid, and (C) Water-soluble polymer compound And a step of carrying out the above-mentioned polymerization, whereby the adhesion of polymer scale in the polymerization vessel is prevented.