JP2005187506A - Method for producing vinylic polymer composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for producing a vinylic polymer composition with which adhesion of polymer scales to the inner wall of the vapor-phase part of a reactor can effectively be prevented and a high-quality product can be obtained with good productivity. <P>SOLUTION: The method for producing the vinylic polymer composition comprises continuously feeding a reaction raw material containing a vinylic monomer having one or more kinds of groups selected from the group consisting of an epoxy group, a hydroxy group and an acid group and a solvent to a tank type reactor and simultaneously and continuously taking out a reaction liquid. The method is characterized as follows. A liquid-phase part which is the reaction liquid containing the vinylic monomer and the solvent and the vapor-phase part are present in the reactor and a part or all of the solvent in which the polymer of the vinylic monomer is soluble in the reaction raw material is continuously fed while being sprayed from a feeding passage separate from the vinylic monomer toward the inner wall of the vapor-phase part of the reactor. Thereby, a polymerizing reaction is carried out. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a continuous solution polymerization method of a vinyl polymer containing a specific vinyl monomer and a solvent, and more specifically, when polymerizing a vinyl polymer, a polymer scale adheres to the inner wall of the gas phase part of the reactor. The present invention relates to a method for producing a vinyl polymer composition that is prevented.

  Conventionally, a method of continuous bulk polymerization or continuous solution polymerization of a vinyl monomer in a reactor equipped with a stirrer is known. In these polymerization methods, polymerization is rarely performed by filling the entire space in the reactor with the polymerization reaction solution for reasons such as removal of reaction heat, safety and operational problems, limitations on the polymerization apparatus, etc. Polymerization is carried out in the presence of a gas phase portion.

  However, when polymerization is performed in a state where the gas phase portion exists, the gaseous monomer present in the gas phase is polymerized in the gas phase portion of the reactor, and a large amount of polymer scale is formed on the inner wall of the gas phase portion of the reactor. May adhere. When such a polymer adheres, it may cause a mechanical abnormality such as blocking of the nozzle or failure of the function of the stirrer. In addition, a polymer scale release scale may be mixed in the product to generate an abnormal product. In addition, removal of the attached polymer scale may require a great deal of labor and time. Thus, when production is carried out on a factory scale, the adhesion of the polymer to the inner wall of the gas phase part of the reactor becomes a big problem.

As a method for preventing the adhesion of the polymer scale to the inner wall of the reactor gas phase part as described above, Patent Document 1 discloses that when a monomer mainly composed of methyl methacrylate is subjected to continuous bulk polymerization, a part of the monomer is removed from the reaction liquid surface. In addition, a method is disclosed in which polymerization is carried out by spraying and supplying uniformly to the reactor wall surface in contact with the reaction liquid surface and the stirring shaft in contact with the reaction liquid surface in a sprayed state. However, according to this method, the effect of suppressing the adhesion of the polymer scale to the reactor gas phase wall surface can be obtained, but when a highly reactive monomer is used as the spray medium, some polymer scale is used. May occur.
Japanese Patent Laid-Open No. 7-149803

  An object of the present invention is to provide a vinyl polymer composition by a continuous solution polymerization method that can effectively prevent the adhesion of polymer scale to the inner wall of the gas phase part of the reactor and obtain a high-quality product with high productivity. It is in providing the manufacturing method of.

  As a result of intensive studies focusing on supply by solvent spraying, the present inventors have found that the above-mentioned problems can be solved by a simple process, and have completed the present invention.

  That is, the present invention continuously supplies a reaction raw material containing a vinyl monomer having one or more groups selected from the group consisting of an epoxy group, a hydroxyl group and an acid group, and a solvent to a tank reactor, In the method for producing a vinyl polymer composition by continuously extracting a reaction liquid at the same time, the reactor includes a liquid phase part which is a reaction liquid containing the vinyl monomer and the solvent, a gas phase part, A part or all of the solvent in which the polymer of the vinyl monomer is soluble in the reaction raw material is sprayed from the supply path different from the vinyl monomer toward the inner wall of the gas phase part of the reactor. It is a method for producing a vinyl polymer composition, wherein the polymerization reaction is carried out while continuously supplying the polymer.

  According to the present invention, in addition to preventing adhesion of polymer scale in continuous solution polymerization, the solvent in the product in which the vinyl polymer is used is used as a spraying solvent, thereby separating and removing the spraying solvent. Without providing it separately, a high-quality vinyl polymer can be obtained with high productivity.

  That is, in the present invention, when continuous reaction polymerization is performed on a reaction raw material containing a vinyl monomer and a solvent, a part or all of the solvent in which the vinyl polymer contained in the reaction raw material is soluble is separated by a separate supply path. Continuously supplying the reactor in the vapor phase toward the inner wall of the gas phase part, and constantly washing away the inner wall of the gas phase of the reactor, effectively preventing the formation of polymer scale, and to the inner wall of the reactor gas phase part. The adhesion of the polymer scale can be suppressed. This makes it possible to obtain a polymer scale adhesion suppressing effect by a very simple method without separating the solvent used for washing.

  Here, the polymer scale is a solid or gel deposit observed in a general reaction apparatus. In the polymerizable monomer, it is considered that the reactive gas in the gas phase stays on the wall surface of the gas phase and aggregates while being polymerized. Therefore, it is important not to make the reactive substance stay on the wall surface. For this purpose, it is preferable that the material in contact with the wall surface is constantly updated. Furthermore, the concentration of the reactive substance in the solution in contact with the wall surface is preferably low. The present inventors have made the present invention in view of such a situation.

  In general, alkyl methacrylate and styrene do not have much polymer scale adhesion, but vinyl monomer having an epoxy group, hydroxyl group or acid group has a problem because the polymer scale adhesion increases. . Generally, since an epoxy group is easy to open a ring, a polymer scale is easily attached. Furthermore, when the polymer scale is attached, it is exposed to a high temperature, whereby the epoxy group is ring-opened to cause a cross-linking reaction, resulting in a solid polymer scale. In addition, regarding the monomer having a hydroxyl group or an acid group, the reason is not clear, but it is easy to form a polymer scale that may be caused by polymerizability with other monomers or interaction with the wall surface.

  According to the present invention, it is possible to prevent scale adhesion by spraying a solvent in which the vinyl polymer is soluble even to such a vinyl monomer to which the polymer scale easily adheres. .

  The solvent used in the present invention is not particularly limited as long as it is inert at the polymerization temperature. For example, aromatic hydrocarbons such as toluene, xylene, SS150 (manufactured by Nippon Petrochemical Co., Ltd.), SS100 (manufactured by Shin Nippon Petrochemical Co., Ltd.); ethyl acetate, ethyl-3-ethoxypropionate And esters such as n-butyl acetate; ketones such as methyl ethyl ketone and methyl isobutyl ketone; and alcohols such as isopropanol and n-butanol.

  Of the above solvents, aromatic hydrocarbons and esters are preferred. Furthermore, as the aromatic hydrocarbons, a mixture of aromatic hydrocarbons having 9 to 10 carbon atoms, and as the esters, propylene glycol monomethyl ether acetate and ethyl 3-ethoxypropionate are more preferable. When such a solvent is used, it becomes possible to more effectively prevent polymer scale adhesion.

  When a low-boiling solvent is used, the pressure in the tank reactor needs to be increased because the pressure in the system increases as the polymerization temperature increases. Such a problem can be solved by using a solvent having a high boiling point. In particular, vinyl monomers having an epoxy group, a hydroxyl group, and an acid group tend to increase the scale adhesion as the polymerization temperature increases, and the scale adheres remarkably when the polymerization temperature is 130 ° C. or higher. In order to avoid increasing the pressure resistance of the tank reactor even at high temperature polymerization, it is preferable to use a solvent having a boiling point of 130 ° C. or higher.

  The amount of the solvent used is preferably determined according to the application of the product in which the finally obtained vinyl polymer is used. It is preferably contained in the reaction raw material at a ratio of 200 parts by mass or less with respect to 100 parts by mass of the vinyl monomer, and further included in the reaction raw material at a ratio of 25 to 100 parts by mass with respect to 100 parts by mass of the vinyl monomer. preferable.

  In order to effectively prevent the adhesion of the polymer scale, it is important not to retain the reactive substance on the wall surface, but there is a method for reducing the reactivity of the reactive substance. As a method of reducing the reactivity of the reactive substance, for example, there is a method of adding a general polymerization inhibitor. In the present invention, such a method can also be taken. However, in the present invention, it is also possible to obtain an effect of effectively preventing adhesion of the polymer scale without taking such a method, that is, without using a substance other than the raw material.

  Furthermore, as a method of reducing the reactivity of the reactive substance, for example, there is a method of lowering the temperature. This method is very effective. That is, the effect of suppressing the polymer scale adhesion is further increased by lowering the temperature of the gas phase wall of the reactor. In addition to reducing the reactivity by lowering the temperature, the effect of positively condensing the gas in the gas phase on the wall surface can be expected. The cooling temperature is not particularly limited as long as it is lower than the polymerization temperature, but is preferably not higher than the boiling point of the spray solvent at the pressure in the gas phase part of the reactor in order to increase the condensation effect. The cooling method is not particularly limited, and includes a method in which a cooling medium is passed through the jacket using a jacket-type reactor, and a method in which the reactor wall surface is cooled with a pipe through which the cooling medium flows.

  In the present invention, for example, continuous solution polymerization can be performed using a general continuous tank reactor equipped with a stirring device, a raw material supply device, and a reaction product extraction device. In this continuous solution polymerization, a general method is to stop the supply of the reaction raw material and to extract the reaction product in the shutdown after the completion of the polymerization. In the case of this method, the solution evaporates on the wall surface after extracting the reaction product and the wall surface is dried, so that the polymer scale may adhere. Therefore, it is preferable to continue spraying the solvent at the time of shutdown because such drying can be prevented and the effect of suppressing the polymer scale adhesion is further increased.

  In the present invention, the method of spraying and supplying the solvent is not particularly limited as long as it wets the wall surface, such as spray, shower, or supply from a slit. However, since the effect of suppressing polymer scale adhesion is increased by reducing the number of portions that do not get wet, a method using a spray nozzle is particularly preferable. Examples of the spray nozzle include a flat spray nozzle, an oblong spray nozzle, an elliptical spray nozzle, a square spray nozzle, a holocorn nozzle, a full cone nozzle, a side spray nozzle, and a porous nozzle. Depending on the shape and size of the reactor, one or a combination of two or more spray nozzles may be used. The material of the spray nozzle is not particularly limited as long as it has corrosion resistance, and stainless steel is usually used.

  The vinyl monomer contained in the reaction raw material is not particularly limited as long as it is a vinyl monomer having one or more groups selected from the group consisting of an epoxy group, a hydroxyl group, and an acid group. What is necessary is just to select according to the use of a polymer. For example, vinyl monomers having an epoxy group, monomers having a hydroxyl group, monomers having an acid group, (meth) acrylic acid esters having a hydrocarbon substituent, styrene monomers, ethylenically unsaturated nitriles, vinyl Examples include esters, ethylenically unsaturated basic vinyl monomers, and α, β-unsaturated vinyl monomers having an N-alkoxyalkyl-substituted amide group. Among these, styrene monomers and acrylic monomers among the above-described monomers are preferably used. This is because a polymer obtained by polymerizing a styrene monomer and / or an acrylic monomer is preferable as a vinyl polymer used for a paint, an adhesive, a coating agent and the like.

  Examples of vinyl monomers having an epoxy group include glycidyl (meth) acrylate, methyl glycidyl (meth) acrylate, and allyl glycidyl ether. Among these, particularly preferable vinyl monomers having an epoxy group include glycidyl (meth) acrylate.

  Examples of the monomer having a hydroxyl group include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 4-hydroxybutyl ( (Meth) acrylate, (meth) acrylic acid ester having a hydroxyalkyl group such as 6-hydroxyhexyl (meth) acrylate, β-butyrolactone ring-opening adduct to 2-hydroxyethyl (meth) acrylate, 2-hydroxyethyl ( Ε-caprolactone ring-opening adduct to (meth) acrylate, ring-opening adduct of ethylene oxide to (meth) acrylic acid, ring-opening adduct of propylene oxide to (meth) acrylic acid, 2-hydroxyethyl (meth) acrylate Or 2-hydroxy Other hydroxyl group-containing vinyl monomers such as (meth) acrylic acid esters having 4-hydroxybutyl vinyl ether, p-hydroxystyrene, etc. having a hydroxyl group at the terminal, such as dimers and trimers of propyl (meth) acrylate It is done. Particularly preferable examples of the monomer having a hydroxyl group include 2-hydroxyethyl (meth) acrylate and 4-hydroxybutyl (meth) acrylate.

  Examples of the monomer having an acid group include monobasic or dibasic vinyl monomers such as methacrylic acid, acrylic acid, crotonic acid, vinyl benzoic acid, fumaric acid, itaconic acid, maleic acid, citraconic acid, maleic anhydride, and the like. Dibasic acid anhydride vinyl monomers such as β-carboxyethyl (meth) acrylate, β-carboxypropyl (meth) acrylate, β- (meth) acryloxyethyl acid succinate, β- (meth) acryloxyethyl acid Maleate, β- (meth) acryloxyethyl acid phthalate, β- (meth) acryloxyethyl acid hexahydrophthalate, β- (meth) acryloxyethyl acid methyl hexahydrophthalate, Y- (meth) acryloxypropyl acid Succinate, 2-hydroxy The terminal hydroxyl group of the ring-opening adduct of ε-caprolactone or Y-butyrolactone to til (meth) acrylate (eg, Plaxel F monomer manufactured by Daicel Chemical Industries, Inc., tone M monomer manufactured by UCC) is succinic anhydride. Caprolactone-modified hydroxyl group-containing (meth) acrylic ester such as succinic acid monoester, phthalic acid monoester or hexahydrophthalic anhydride monoester esterified with phthalic anhydride or hexahydrophthalic anhydride and introduced with a carboxyl group at the terminal Long chain carboxyl group-containing vinyl monomers such as monoester reaction products of acid ester and dibasic acid anhydride, monomethyl maleate, monoethyl maleate, monobutyl maleate, monooctyl maleate, monomethyl itaconate, monoethyl itaconate, Monobutyl itaconate, ita Monoesters of dibasic acid or dibasic anhydride vinyl monomers such as monooctyl acrylate, mono-2-ethylhexyl itaconate, monomethyl fumarate, monoethyl fumarate, monobutyl fumarate, monooctyl fumarate, monoethyl citraconic acid Etc. A particularly preferable monomer having an acid group includes maleic anhydride.

  Examples of (meth) acrylic acid esters having a hydrocarbon substituent include methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, n-butyl (meth) acrylate, i-butyl ( (Meth) acrylate, t-butyl (meth) acrylate, sec-butyl (meth) acrylate, n-pentyl (meth) acrylate, n-octyl (meth) acrylate, lauryl (meth) acrylate, stearyl (meth) acrylate, tridecyl ( Examples include meth) acrylate, 2-ethylhexyl (meth) acrylate, cyclohexyl (meth) acrylate, phenyl (meth) acrylate, benzyl (meth) acrylate, and isobornyl (meth) acrylate.

  Examples of the styrene monomer include styrene, o-methyl styrene, m-methyl styrene, p-methyl styrene, α-methyl styrene, p-ethyl styrene, 2,4-dimethyl styrene, pn-butyl styrene, p. -Tert-butyl styrene, pn-hexyl styrene, pn-octyl styrene, pn-nonyl styrene, pn-decyl styrene, pn-dodecyl styrene, p-phenyl styrene, 3,4- Examples thereof include styrene derivatives such as dichlorosyl styrene and vinyl toluene.

  Among these, particularly preferable styrenic monomers include styrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, α-methylstyrene, p-ethylstyrene, 2,4-dimethylstyrene, and pn-. Butyl styrene, p-tert-butyl styrene, pn-hexyl styrene, pn-octyl styrene, pn-nonyl styrene, pn-decyl styrene, pn-dodecyl styrene, p-phenyl styrene, 3,4-Dichlorosyl styrene, vinyl toluene, etc. are mentioned.

  Examples of the ethylenically unsaturated nitriles include acrylonitrile and methacrylonitrile.

  Examples of vinyl esters include vinyl acetate.

  Examples of the ethylenically unsaturated basic vinyl monomers include dimethylaminoethyl (meth) acrylate and diethylaminoethyl (meth) acrylate.

  Examples of α, β-unsaturated vinyl monomers having an N-alkoxyalkyl-substituted amide group include N-methoxymethyl acrylamide, N-methoxymethyl methacrylamide, N-ethoxymethyl acrylamide, N-propoxymethyl acrylamide, N -Butoxymethyl acrylamide etc. are mentioned. These may be used alone or in combination of two or more as required.

  Particularly preferable acrylic monomers among the above-mentioned vinyl monomers include methyl (meth) acrylate, ethyl (meth) acrylate, n-butyl (meth) acrylate, t-butyl (meth) acrylate, i-butyl ( (Meth) acrylic acid having a hydrocarbon substituent such as (meth) acrylate, n-octyl (meth) acrylate, lauryl (meth) acrylate, stearyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, isobornyl (meth) acrylate, etc. (Meth) acrylic acid ester which has hydroxyalkyl groups, such as ester, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, is mentioned.

  In the polymerization step, a polymerization initiator as a polymerization accelerator can be contained in the reaction raw material and supplied to the reactor.

  The polymerization initiator is not particularly limited as long as it can be decomposed at the polymerization temperature to generate radicals. For example, 2,2-bis (4,4-di-t-butylperoxycyclohexyl) propane, t-butylperoxy 2 -Ethyl hexanoate, t-butyl peroxylaurate, t-butyl peroxy 3,5,5-trimethylhexanoate, cyclohexanone peroxide, t-butyl peroxyisopropyl carbonate, t-butyl peroxyacetate, t -Butylperoxybenzoate, t-hexylperoxy 2-ethylhexanoate, dicumyl peroxide, t-butylcumyl peroxide, diisopropylbenzene hydroperoxide, di-t-butyl peroxide, di-t-amylper Oxide, di-t-hexyl par Organic peroxides such as oxide, p-methane hydroperoxide, cumene hydroperoxide, t-butyl hydroperoxide, azobisisobutylnitrile, azobisvaleronitrile, 2- (carbamoylazo) isobutyronitrile, 2, Azo compounds such as 2-azobis (2,4,4-trimethylpentane) and 2-phenylazo-2,4-dimethyl-4-methoxyvaleronitrile, persulfates such as potassium persulfate, redox polymerization initiators, etc. The amount of such a polymerization initiator used is not particularly limited and is appropriately determined depending on the polymerization temperature and the target polymer addition rate, but is usually 0.001 with respect to 100 parts by mass of the vinyl monomer. What is contained in the ratio of -12 mass parts is preferable.

  In the present invention, since the product using the finally obtained vinyl polymer contains a solvent, it is not necessary to separate and remove the solvent from the vinyl polymer after obtaining the vinyl polymer. By doing so, it is not necessary to remove a solvent that requires a lot of labor and a large amount of energy, and the cost required for the production of the vinyl polymer is further reduced.

  Hereinafter, the present invention will be described in more detail with reference to examples. In the following description, “part” means “part by mass”.

[Example 1]
Using a continuous tank reactor equipped with a stirring blade, a raw material supply line, a polymer discharge line, a nitrogen pressure line, and a temperature control device, 10 parts of styrene, 35 parts of i-butyl methacrylate, 35 parts of glycidyl methacrylate, 2- To 20 parts of hydroxyethyl methacrylate, 10 parts of SS150 (Shin Nippon Petrochemical Co., Ltd.) as a solvent and 5 parts of ditertiary butyl peroxide (Nippon Yushi Co., Ltd., trade name Perbutyl D) as a polymerization initiator are added. The reaction raw material was continuously supplied to a reactor maintained at 220 ° C. and 1.0 MPa so that the residence time was 10 minutes, and polymerization was performed. At the same time, one spray nozzle was used as a spraying solvent for SS150 in a 20-part supply path, and was supplied to the reactor gas-phase wall surface in a spray form. Moreover, the reaction polymer was continuously extracted from the reactor with a gear pump. When steady operation was carried out for 3 hours, there was some film-like contamination in the reactor, but no polymer scale was observed.

[Example 2]
The polymerization reaction was performed in the same manner as in Example 1 except that the reactor gas phase was cooled by the cooling jacket. When steady operation was carried out for 3 hours, there was some film-like contamination in the reactor, but no polymer scale was observed.

[Example 3]
Using a continuous tank reactor equipped with a stirring blade, a raw material supply line, a polymer discharge line, a nitrogen pressurization line, a temperature control device, and a cooling jacket for the gas phase part, 75 parts of styrene, 20 parts of n-butyl acrylate, Residence time of a reaction raw material obtained by adding 10 parts of SS150 as a solvent and 4 parts of ditertiary butyl peroxide as a polymerization initiator to 5 parts of 4-hydroxybutyl acrylate in a reactor maintained at 220 ° C. and 1.0 MPa Was continuously fed and polymerized so as to be 10 minutes. At the same time, SS150 was sprayed as a spray solvent in a 10-part supply path, and was sprayed to the reactor gas phase wall surface cooled by the cooling jacket. Moreover, the reaction polymer was continuously extracted from the reactor with a gear pump. When steady operation was performed for 3 hours, no polymer scale was observed in the reactor.

[Example 4]
Using the same continuous tank reactor as in Example 3, 35 parts of styrene, 35 parts of methyl methacrylate, 30 parts of maleic anhydride, 20 parts of propylene glycol monomethyl ether acetate as a solvent, and ditertiary butyl peroxide 6 as a polymerization initiator The reaction raw material to which the part was added was continuously fed to a reactor maintained at 200 ° C. and 1.0 MPa so that the residence time was 10 minutes, and polymerization was performed. At the same time, 20 parts of propylene glycol monomethyl ether acetate as a spraying solvent was supplied to the reactor gas phase part wall surface cooled by the cooling jacket in a spray form using one spray nozzle in a separate supply path. Moreover, the reaction polymer was continuously extracted from the reactor with a gear pump. When steady operation was performed for 4 hours, no polymer scale was observed in the reactor.

[Comparative Example 1]
The polymerization reaction was carried out in the same manner as in Example 1 except that the solvent was not sprayed and the amount of the solvent (SS150) in the reaction raw material was increased to 30 parts. As a result of observing the inside of the reactor after steady operation for 3 hours, adhesion of a reactor gas phase wall and a hard layered polymer scale was observed. Moreover, adhesion of a solid polymer scale was seen in the stirring shaft part. Although 2 g of this polymer scale was immersed in 15 g of acetone, toluene, and SS150, and held at 25 ° C. for 5 hours, it did not dissolve in any solvent.

[Comparative Example 2]
The polymerization reaction was carried out in the same manner as in Example 2 except that the solvent was not supplied in a spray form and the amount of the solvent (SS150) in the reaction raw material was increased to 30 parts. As a result of observing the inside of the reactor after steady operation for 3 hours, some film-like polymer scale was attached to the cooling jacket portion of the gas phase portion. In addition, adhesion of a hard film-like polymer scale was observed in an uncooled portion of the gas phase portion. Furthermore, adhesion of a solid polymer scale was observed on the stirring shaft.

[Comparative Example 3]
The polymerization reaction was carried out in the same manner as in Example 1 except that 20 parts in 130 parts of the reaction raw material not containing a polymerization initiator was supplied as a spraying medium instead of the solvent. As a result of observing the inside of the reactor, some film-like polymer scale was adhered to the wall surface of the gas phase part of the reactor. Further, a slight amount of solid polymer scale adhered to the stirring shaft.

[Evaluation results]
As is clear from the results described above, Example 1 uses a solvent as the spray medium, so the effect of washing away the wall surface of the gas phase in the reactor is large, and no adhesion of polymer scale was observed after operation. Some film-like dirt was confirmed. In Examples 2 to 4, in addition to Example 1, by combining jacket cooling of the gas phase part of the reactor, the effect of suppressing polymer scale is large on the wall surface of the gas phase part, and adhesion of polymer scale is observed. Although no film-like soiling was observed in the liquid phase part. Adhesion and contamination of the polymer scale were not confirmed.

  On the other hand, in Comparative Example 1, since there is no spraying medium, the reactor gas-phase part wall surface cannot be washed away, and since the gas-phase part is not cooled, the gaseous monomer present in the gas-phase part Condensation cannot be carried out effectively, and condensation continues on the wall surface of the gas phase in the reactor and the monomer continues to stay on the wall surface, causing abnormal polymerization, and a polymer scale that is insoluble in the solvent is formed on almost the entire wall surface of the gas phase. It has formed. In Comparative Example 2, the effect of suppressing the polymer scale at the cooling portion was observed due to the effect of the cooling jacket. However, it was confirmed that the polymer scale adhered to the uncooled portion of the gas phase portion and the stirring shaft portion. In Comparative Example 3, since the reaction raw material was used as the spraying medium, there was an effect of washing away the reactor gas phase wall surface. However, since the spray medium itself is a reactive liquid, a slight amount of weight is applied to the reactor gas phase wall surface and the stirring shaft. The adhesion of the coal scale was confirmed, and the adhesion of the polymer scale was not completely prevented.

  The evaluation results of Examples 1 to 4 and Comparative Examples 1 to 3 are collectively shown in Table 1 below.

Claims (9)

A reaction raw material containing a vinyl monomer having one or more groups selected from the group consisting of an epoxy group, a hydroxyl group and an acid group, and a solvent is continuously supplied to the tank reactor, and the reaction solution is continuously supplied. In the method of producing a vinyl polymer composition by extracting into
In the reactor, there are a liquid phase part which is a reaction liquid containing the vinyl monomer and the solvent, and a gas phase part, and the polymer of the vinyl monomer is soluble in the reaction raw material. A vinyl polymer characterized in that a polymerization reaction is carried out by continuously supplying a part or all of a solvent from a supply path separate from the vinyl monomer while spraying toward the gas phase inner wall of the reactor. A method for producing the composition. The method for producing a vinyl polymer according to claim 1, wherein the solvent is an aromatic hydrocarbon and / or an ester. The method for producing a vinyl polymer according to claim 2, wherein the solvent is an aromatic hydrocarbon and / or an ester having a boiling point of 130 ° C or higher. The method for producing a vinyl polymer according to claim 2 or 3, wherein the aromatic hydrocarbon is a mixture of an aromatic hydrocarbon having 9 to 10 carbon atoms. The method for producing a vinyl polymer according to any one of claims 2 to 4, wherein the esters are propylene glycol monomethyl ether acetate and / or ethyl 3-ethoxypropionate. The method for producing a vinyl polymer according to any one of claims 1 to 5, wherein the gas phase wall surface of the reactor is cooled below the boiling point of the spray solvent at the gas phase pressure. The method for producing a vinyl polymer according to any one of claims 1 to 6, wherein the vinyl monomer having an epoxy group is glycidyl (meth) acrylate. The method for producing a vinyl polymer according to any one of claims 1 to 7, wherein the vinyl monomer having a hydroxyl group is 2-hydroxyethyl (meth) acrylate and / or 4-hydroxybutyl (meth) acrylate. The method for producing a vinyl polymer according to any one of claims 1 to 8, wherein the vinyl monomer having an acid group is maleic anhydride.