JP2016089030A - Manufacturing method of polymer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing a polymer by polymerizing monomers having a vinyl bond at high productivity, where the polymer has polymerization percentage of 60% or more which was difficult to discharge stably as high viscosity and is high molecular weight polymer.SOLUTION: There is provided a manufacturing method of a polymer by melting or dissolving monomers having a vinyl bond by contacting the monomer having the vinyl bond and compressive fluid with a mixing ratio satisfying a relationship of the following formula (1) by using a polymerization reaction machine, thereafter addition-polymerizing the monomers having the vinyl bond in a presence of an initiator and discharging the resulting polymer from the polymerization reaction machine. 0.5≤mass of raw material/(mass of raw material+mass of compressive fluid)≤0.9 (1)SELECTED DRAWING: None

Description

  The present invention relates to a method for producing a polymer in which a monomer having a vinyl bond is subjected to addition polymerization.

  Radical polymerization is a polymerization method in which radicals are generated by decomposition of an initiator and a monomer having a vinyl bond is addition-polymerized, and is widely used industrially.

  Examples of a method for continuously obtaining such a polymer include suspension polymerization, solution polymerization, and bulk polymerization. When a methacrylic polymer composition is produced by a multistage polymerization method of suspension polymerization, transparency is impaired because a dispersion stabilizer or an emulsifier is used. In the case of the solution polymerization method, generally, there arises a problem that the thermal decomposition resistance of the polymer is lowered by the solvent, and the method of recovering the solvent and the monomer becomes complicated.

  On the other hand, in the case of bulk polymerization, reaction control is difficult because the viscosity of the reaction mixture increases. As a system that does not contain a solvent and enables reaction control in bulk polymerization in bulk polymerization, a method of polymerizing to a polymerization rate of 1 to 50% and then adding a chain transfer agent to polymerize to a polymerization rate of 60% or more Is known (Patent Document 1). However, in this method, repolymerization is performed at 60 ° C. for 10 hours in the second stage, and the required time is long and the productivity is not sufficient.

  In order to increase productivity in bulk polymerization, it is desired to shorten the polymerization time and increase the polymerization rate. However, since the viscosity increases when the polymerization rate is increased, it is necessary to select an appropriate polymerization rate. When the polymerization rate is 70% or more, the viscosity of the reaction mixture increases, and the amount of heat generated by the polymerization also increases. Therefore, when removing heat to keep the temperature constant in the polymerization reaction of the reaction system, Or rapid cooling is likely to occur. As a result, the adhesion and growth of the gel on the inner wall surface of the reaction tank become more remarkable, and problems such as gelled products being mixed as impurities in the resulting polymer composition may occur.

In the continuous polymerization method by bulk polymerization, it is obvious that the higher the polymerization rate in the polymerization tank, the higher the productivity. However, in general, in bulk polymerization of PMMA, it is known that when the polymerization rate increases, a reaction rate acceleration phenomenon occurs due to the gel effect. Therefore, when continuous bulk polymerization is performed using a single tank reactor, there is a limit polymerization rate that allows operation while stably controlling the reaction with respect to the polymerization temperature. As a means for increasing the limiting polymerization rate, it is known that a stable operation is possible in a polymerization rate range of 45% to 70% by using a radical initiator having a half-life of 0.5 to 120 seconds ( For example, see Patent Document 2 and Patent Document 3).
Accordingly, there is a demand for polymerization conditions with a high polymerization rate that are short in polymerization time and less likely to cause gelation and growth.
However, when a monomer having a vinyl bond is polymerized at a low temperature as described above without using an organic solvent, the viscosity of the reaction product increases with the progress of the reaction, which makes it difficult for the polymerization reaction to proceed. Challenges arise.

The technique disclosed in Japanese Patent No. 5182439 performs the reaction in a batch polymerization apparatus in a state where the amount of compressive fluid is larger than the amount of monomer, and corresponds to so-called heterogeneous polymerization. In this case, the uneven distribution of particles is suppressed by adding a dispersant.
In a continuous polymerization process, it is not economically preferable to add compressed fluid to the extent that the contents are non-uniform, and short paths and abnormal stagnation are likely to occur in the piping, resulting in product flow as a result of long-term operation. Unspecificity may occur. Therefore, it is preferable that the contents are uniform.

  The present invention is a method for producing a polymer by polymerizing a monomer having a vinyl bond, and a high-molecular weight polymer having a polymerization rate of 60% or more, which has heretofore been difficult to stably discharge with a high viscosity. It aims at providing the method which can be manufactured with high productivity.

The present inventors contact a monomer having a vinyl bond and a compressive fluid at a predetermined mixing ratio to melt or dissolve the monomer having a vinyl bond, and then have the vinyl bond in the presence of an initiator. The present invention was completed by finding that the above-mentioned problems can be solved by addition polymerization of monomers.
That is, the present invention is a method for producing a polymer as described in (1) below.

(1) Using a polymerization reactor, a monomer having a vinyl bond and a compressive fluid were brought into contact with each other at a mixing ratio satisfying the relationship of the following formula (1) to melt or dissolve the monomer having a vinyl bond. A method for producing a polymer, wherein the monomer having a vinyl bond is subjected to addition polymerization in the presence of an initiator, and the obtained polymer is discharged from a polymerization reaction apparatus.

According to the production method of the present invention, a polymer having a polymerization rate of 60% or more can be produced with high productivity without using an organic solvent.
In addition, it becomes easy to increase the molecular weight by selecting a compressed fluid such as carbon dioxide that hardly undergoes radical chain transfer.
Further, a polymer having high stereoregularity, that is, high heat resistance can be obtained by polymerizing a monomer having a vinyl bond at a low temperature below the melting point or softening point of the polymer to be produced.

It is a general phase diagram showing the state of a substance with respect to temperature and pressure. It is a phase diagram for defining the range of compressive fluid in this embodiment. It is a systematic diagram which shows an example of a superposition | polymerization process. It is a systematic diagram showing an example of a continuous polymerization process.

Hereinafter, embodiments of the present invention will be described in detail.
Note that it is easy for a person skilled in the art to make other embodiments by changing or correcting the present invention within the scope of the claims, and these changes and modifications are included in the scope of the claims. The following description exemplifies an embodiment of the present invention, and does not limit the scope of the claims.

In the method for producing a polymer according to this embodiment, a monomer having an addition-polymerizable vinyl bond and a compressive fluid are brought into contact with each other to melt or dissolve the monomer having a vinyl bond, and then in the presence of an initiator, It is characterized by addition polymerization of a monomer having a bond.
Hereinafter, a monomer having a vinyl bond capable of addition polymerization may be simply referred to as a monomer, and the addition polymerization may be simply referred to as polymerization.

  As a result of extensive research, the inventors of the present invention, for example, contacted a compressive fluid without radical chain transfer with an addition-polymerizable monomer having a vinyl group and a polymer product composed thereof, to thereby obtain a mixture of these mixtures. We found that the viscosity decreased. As a result, since the reaction product is in a molten state even at a reaction temperature below the melting point or softening point of the polymer, the reaction proceeds even in the reaction below the above temperature, and the polymer after the reaction can be easily taken out. In addition, the manufacturing method of the polymer of this embodiment can be applied suitably in manufacture of the polymer from which a viscosity falls with a compressed fluid. Furthermore, according to the manufacturing method of the present embodiment, the reaction temperature can be set low and the viscosity can be reduced without using an organic solvent, so that the reaction heat can be easily controlled.

<< Raw materials >>
First, components such as a monomer having a vinyl bond used as a raw material in the above production method and an initiator used will be described. In the present embodiment, the raw material is a material that is a constituent component of the polymer, includes a monomer, and further includes optional components such as an initiator and an additive appropriately selected as necessary.

<Monomer>
In the production method of this embodiment, examples of the applicable monomer include monomers having a vinyl bond to which radical polymerization is generally applicable. Monomers to which radical polymerization can be applied include various monomers having a vinyl bond that can be radically polymerized by a known method.

  The monomer to which radical polymerization can be applied depends on the type, position and number of substituents directly bonded to the double bond, but mono-substituted ethylene such as polystyrene, 1,1-disubstituted ethylene such as polymethacrylate, etc. Can be given. Examples of monomers include styrene monomers such as styrene derivatives, acrylic monomers such as acrylate, methacrylate, acrylic acid and methacrylic acid, acrylamide monomers such as acrylonitrile and acrylamide, diene monomers such as chloroprene, vinyl acetate, and methyl vinyl. Although ketone is mentioned, it is not limited to this.

  Examples of the styrene derivative include styrene and 4-methylstyrene. Examples of the acrylate include methyl acrylate. Examples of the methacrylate include dimethylaminoethyl methacrylate and methyl methacrylate. These polymerizations can be performed alone, but a copolymer may be obtained by combining two or more.

<Initiator (polymerization initiator)>
The radical initiator used in the present invention is not particularly limited as long as the half-life at the polymerization temperature is within 1 minute. Those having a half-life of more than 1 minute are undesirable because the reaction rate is slow. The relationship between the temperature and half-life of the radical initiator is described in various literatures and technical data of manufacturers for each type of radical initiator.

  Specific examples of the radical initiator include azobisisobutyronitrile, azobisdimethylvaleronitrile, azobiscyclohexanenitrile, 1,1′-azobis (1-acetoxy-1-phenylethane), dimethyl 2,2 ′. -Azo compounds such as azobisisobutyrate and 4,4'-azobis-4-cyanovaleric acid; benzoyl peroxide, lauroyl peroxide, acetyl peroxide, caprylyl peroxide, 2,4-dichlorobenzoyl peroxide , Isobutyl peroxide, acetylcyclohexylsulfonyl peroxide, tbutyl peroxypivalate, t-butylperoxyneodecanoate, t-butylperoxyneoheptanoate, t-butylperoxy-2-ethylhexanoate 1,1-di t-butylperoxy) cyclohexane, 1,1-di (t-butylperoxy) -3,3,5-trimethylcyclohexane, 1,1-di (t-hexylperoxy) -3,3,5-trimethyl Cyclohexane, isopropyl peroxydicarbonate, isobutyl peroxydicarbonate, s-butyl peroxydicarbonate, n-butyl peroxydicarbonate, 2-ethylhexyl peroxydicarbonate, bis (4-t-butylcyclohexyl) peroxydi Carbonate, t-amylperoxy-2-ethylhexanoate, 1,1,3,3-tetramethylbutylperoxy-ethylhexanoate, 1,1,2-trimethylpropylperoxy-2-ethylhexanoate Ate, t-butylperoxyisopropyl monocar Nate, t-amyl peroxyisopropyl monocarbonate, t-butyl peroxy-2-ethylhexyl carbonate, t-butyl peroxyallyl carbonate, t-butyl peroxyisopropyl carbonate, 1,1,3,3-tetramethylbutylper Oxyisopropyl monocarbonate, 1,1,2-trimethylpropyl peroxyisopropyl monocarbonate, 1,1,3,3-tetramethylbutyl peroxyisononate, 1,1,2-trimethylpropyl peroxyisononate, t -Organic peroxides such as butyl peroxybenzoate. These polymerization initiators may be used alone or in a combination of two or more.

  The supply amount of the polymerization initiator (radical initiator) is not particularly limited, but is adjusted according to the molecular weight to be obtained. Usually, it is 0.001-1 mass% with respect to a raw material monomer. The radical initiator may be dissolved in the monomer in advance and supplied to the polymerization reaction tank.

  In addition to the above raw material monomers and polymerization initiator, any appropriate other components such as chain transfer agents, release agents, rubbery polymers such as butadiene and styrene butadiene rubber (SBR), heat stabilizers, ultraviolet rays Absorbents may be used. Chain transfer agents are used to adjust the molecular weight of the polymer produced. A mold release agent is used in order to improve the moldability of the resin composition obtained from a polymer composition. A heat stabilizer is used in order to suppress thermal decomposition of the produced polymer. An ultraviolet absorber is used in order to suppress deterioration by the ultraviolet-ray of the polymer to produce | generate.

  The chain transfer agent may be a monofunctional or polyfunctional chain transfer agent. Specifically, for example, n-propyl mercaptan, isopropyl mercaptan, n-butyl mercaptan, t-butyl mercaptan, n-hexyl mercaptan, n-octyl mercaptan, 2-ethylhexyl mercaptan, n-dodecyl mercaptan, t-dodecyl mercaptan, etc. Alkyl mercaptans such as phenyl mercaptan and thiocresol; mercaptans having 18 or less carbon atoms such as ethylene thioglycol; ethylene glycol, neopentyl glycol, trimethylolpropane, pentaerythritol, dipentaerythritol, tripentaerythritol, Polyhydric alcohols such as sorbitol; hydroxyl group esterified with thioglycolic acid or 3-mercaptopropionic acid, 1,4- Tetrahydronaphthalene, 1,4,5,8-tetrahydronaphthalene, beta-terpinene, terpinolene, 1,4-cyclohexadiene, and the like hydrogen sulfide. These may be used alone or in combination of two or more.

  The release agent is not particularly limited, and examples thereof include higher fatty acid esters, higher aliphatic alcohols, higher fatty acids, higher fatty acid amides, and higher fatty acid metal salts. In addition, only 1 type may be sufficient as a mold release agent, and 2 or more types may be sufficient as it.

  Specific examples of higher fatty acid esters include, for example, methyl laurate, ethyl laurate, propyl laurate, butyl laurate, octyl laurate, methyl palmitate, ethyl palmitate, propyl palmitate, butyl palmitate, palmitic acid. Octyl, methyl stearate, ethyl stearate, propyl stearate, butyl stearate, octyl stearate, stearyl stearate, myristyl myristate, methyl behenate, ethyl behenate, propyl behenate, butyl behenate, octyl behenate, etc. Saturated fatty acid alkyl: methyl oleate, ethyl oleate, propyl oleate, butyl oleate, octyl oleate, methyl linoleate, ethyl linoleate, propyl linoleate, butyl linoleate And unsaturated fatty acid alkyls such as octyl linoleate; lauric acid monoglyceride, lauric acid diglyceride, lauric acid triglyceride, palmitic acid monoglyceride, palmitic acid diglyceride, palmitic acid triglyceride, stearic acid monoglyceride, stearic acid diglyceride, stearic acid triglyceride, behenic acid Saturated fatty acid glycerides such as monoglyceride, behenic acid diglyceride and behenic acid triglyceride; and unsaturated fatty acid glycerides such as oleic acid monoglyceride, oleic acid diglyceride, oleic acid triglyceride, linoleic acid diglyceride and linoleic acid triglyceride. Among these, methyl stearate, ethyl stearate, butyl stearate, octyl stearate, stearic acid monoglyceride, stearic acid diglyceride, stearic acid triglyceride and the like are preferable.

  Specific examples of the higher aliphatic alcohol include saturated aliphatic alcohols such as lauryl alcohol, palmityl alcohol, stearyl alcohol, isostearyl alcohol, behenyl alcohol, myristyl alcohol, cetyl alcohol; oleyl alcohol, linolyl alcohol, and the like. Examples include unsaturated fatty alcohols. Of these, stearyl alcohol is preferred.

  Specific examples of higher fatty acids include, for example, caproic acid, caprylic acid, capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, arachidic acid, behenic acid, lignoceric acid, and 12-hydroxyoctadecanoic acid. Fatty acids; unsaturated fatty acids such as palmitoleic acid, oleic acid, linoleic acid, linolenic acid, cetreic acid, erucic acid, ricinoleic acid and the like.

  Specific examples of the higher fatty acid amide include saturated fatty acid amides such as lauric acid amide, palmitic acid amide, stearic acid amide, and behenic acid amide; unsaturated fatty acid amides such as oleic acid amide, linoleic acid amide, and erucic acid amide. Amides; Amides such as ethylene bislauric acid amide, ethylene bispalmitic acid amide, ethylene bisstearic acid amide, and N-oleyl stearamide. Of these, stearic acid amide and ethylenebisstearic acid amide are preferable.

  Examples of the higher fatty acid metal salt include sodium salts, potassium salts, calcium salts and barium salts of the higher fatty acids described above.

  It is preferable to adjust the usage-amount of a mold release agent so that it may become 0.01-1.0 mass part with respect to 100 mass parts of polymers (polymer) contained in the polymer composition obtained. It is more preferable to adjust so that it may become 01-0.50 mass part.

  The heat stabilizer is not particularly limited, and examples thereof include phosphorus heat stabilizers and organic disulfide compounds. Of these, organic disulfide compounds are preferred. In addition, only 1 type may be sufficient as a heat stabilizer, and 2 or more types may be sufficient as it.

  Examples of the phosphorus-based heat stabilizer include tris (2,4-di-t-butylphenyl) phosphite, 2-[[2,4,8,10-tetrakis (1,1-dimethylethyl) dibenzo [d. , F] [1,3,2] dioxaphosphin-6-yl] oxy] -N, N-bis [2-[[2,4,8,10-tetrakis (1,1-dimethylethyl) Dibenzo [d, f] [1,3,2] dioxaphosphin-6-yl] oxy] -ethyl] ethanamine, diphenyltridecyl phosphite, triphenyl phosphite, 2,2-methylenebis (4,6 -Di-tert-butylphenyl) octyl phosphite, bis (2,6-di-tert-butyl-4-methylphenyl) pentaerythritol diphosphite, and the like. Among these, 2,2-methylenebis (4,6-di-tert-butylphenyl) octyl phosphite is preferable.

  Examples of organic disulfide compounds include dimethyl disulfide, diethyl disulfide, di-n-propyl disulfide, di-n-butyl disulfide, di-sec-butyl disulfide, di-tert-butyl disulfide, di-tert-amyl disulfide, dicyclohexyl. Examples thereof include disulfide, di-tert-octyl disulfide, di-n-dodecyl disulfide, di-tert-dodecyl disulfide and the like. Among these, di-tert-alkyl disulfide is preferable, and di-tert-dodecyl disulfide is more preferable.

  It is preferable that the usage-amount of a heat stabilizer is 1-2000 mass ppm with respect to the polymer (polymer) contained in the polymer composition obtained. When molding a polymer composition (more specifically, a resin composition after devolatilization) in order to obtain a molded body from the polymer composition of the present invention, the molding temperature is set high for the purpose of increasing molding efficiency. In such a case, it is more effective to add a heat stabilizer.

  Examples of the ultraviolet absorber include benzophenone ultraviolet absorbers, cyanoacrylate ultraviolet absorbers, benzotriazole ultraviolet absorbers, malonic ester ultraviolet absorbers, and oxalanilide ultraviolet absorbers. An ultraviolet absorber may be used independently and may be used in combination of 2 or more type. Among these, benzotriazole type ultraviolet absorbers, malonic acid ester type ultraviolet absorbers, and oxalanilide type ultraviolet absorbers are preferable.

  Examples of the benzophenone-based UV absorber include 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-methoxybenzophenone-5-sulfonic acid, 2-hydroxy-4-octyloxybenzophenone, Examples include 4-dodecyloxy-2-hydroxybenzophenone, 4-benzyloxy-2-hydroxybenzophenone, 2,2′-dihydroxy-4,4′-dimethoxybenzophenone.

  Examples of the cyanoacrylate ultraviolet absorber include ethyl 2-cyano-3,3-diphenylacrylate, 2-ethylhexyl 2-cyano-3,3-diphenylacrylate, and the like.

  Examples of the benzotriazole ultraviolet absorber include 2- (2-hydroxy-5-methylphenyl) -2H-benzotriazole and 5-chloro-2- (3,5-di-t-butyl-2-hydroxyphenyl). ) -2H-benzotriazole, 2- (3-t-butyl-2-hydroxy-5-methylphenyl) -5-chloro-2H-benzotriazole, 2- (3,5-di-t-pentyl-2- Hydroxyphenyl) -2H-benzotriazole, 2- (3,5-di-tert-butyl-2-hydroxyphenyl) -2H-benzotriazole, 2- (2H-benzotriazol-2-yl) -4-methyl- 6- (3,4,5,6-tetrahydrophthalimidylmethyl) phenol, 2- (2-hydroxy-5-t-octylphenyl) -2H-benzoto Azoles and the like.

  As the malonic acid ester ultraviolet absorber, 2- (1-arylalkylidene) malonic acid esters are usually used, and examples thereof include 2- (paramethoxybenzylidene) malonic acid dimethyl.

  As the oxalanilide ultraviolet absorber, 2-alkoxy-2'-alkyloxalanilides are usually used, and examples thereof include 2-ethoxy-2'-ethyloxalanilide.

  The used amount of the ultraviolet absorber is 5 to 1000 mass ppm with respect to the polymer (polymer) contained in the obtained polymer composition. Preferably there is.

<< Compressive fluid >>
Next, the compressive fluid used in the manufacturing method of this embodiment will be described with reference to FIGS. 1 and 2. FIG. 1 is a phase diagram showing the state of a substance with respect to temperature and pressure. FIG. 2 is a phase diagram for defining the range of the compressible fluid in the present embodiment. In the present embodiment, the “compressible fluid” means that a substance exists in any of the regions (1), (2), and (3) shown in FIG. 2 in the phase diagram shown in FIG. It means the state of time.

  In such a region, it is known that the substance has a very high density and behaves differently from that at normal temperature and pressure. In addition, when a substance exists in the area | region of (1), it becomes a supercritical fluid. A supercritical fluid is a fluid that exists as a non-condensable high-density fluid in a temperature and pressure region that exceeds the limit (critical point) at which gas and liquid can coexist, and does not condense even when compressed. Since the supercritical fluid has transport properties intermediate between liquid and gas and has excellent mass transfer and heat transfer characteristics, the polymerization reaction in the supercritical fluid is also effective for removing the polymerization heat. Further, when the substance is present in the region (2), it becomes a liquid, but in this embodiment, it is obtained by compressing a substance that is in a gaseous state at normal temperature (25 ° C.) and normal pressure (1 atm). Represents liquefied gas. Further, when the substance is present in the region (3), it is in a gaseous state, but in the present embodiment, it represents a high pressure gas whose pressure is 1/2 (1/2 Pc) or more of the critical pressure (Pc).

  As the substance that can be used as the compressive fluid, a substance that plasticizes the polymer to be produced without impairing the activity of the material to be used is preferable. The compressible fluid that can plasticize the polymer to be produced is not particularly limited. For example, in the case of an acrylate or methacrylate having an ester group in the side chain, carbon monoxide; carbon dioxide is suitable. Other examples of the compressed fluid include dinitrogen monoxide; nitrogen; hydrocarbons such as methane, ethane, propane, 2,3-dimethylbutane, ethylene, and ethers such as dimethyl ether and methyl ethyl ether. Among these, carbon dioxide has a critical pressure of about 7.4 MPa, a critical temperature of about 31 ° C., can easily create a supercritical state, is nonflammable and easy to handle, and radical chain transfer is unlikely to occur. This is preferable. These compressive fluids may be used alone or in combination of two or more.

  According to this embodiment, the monomer can be melted or dissolved by contacting the compressive fluid and the monomer without using an organic solvent. In the present embodiment, “melting” means a state in which a raw material or a produced polymer comes into contact with a compressive fluid and is plasticized or liquefied while swelling. Further, “dissolving” means that the raw material is dissolved in the compressive fluid. Even a monomer that is liquid at normal pressure is considered to be dissolved by forming a homogeneous phase with the compressed fluid.

<< Polymerization reactor >>
Subsequently, a polymerization reaction apparatus used for polymer production in the present embodiment will be described with reference to FIGS. 3 and 4.
FIG. 3 is a view showing a batch polymerization reaction apparatus, and FIG. 4 is a view showing a continuous polymerization reaction apparatus.

<Batch polymerization reactor>
First, the batch polymerization reaction apparatus 200 will be described with reference to FIG. FIG. 3 is a system diagram showing an example of a polymerization process. In the system diagram of FIG. 3, the polymerization reaction apparatus 200 has a tank 21, a metering pump 22, an addition pot 25, a reaction vessel 27, and valves (23, 24, 26, 28, 29). . Each of the above devices is connected as shown in FIG. Further, the pipe 30 is provided with joints (30a, 30b).

  The tank 21 stores a compressible fluid. The tank 21 may store a gas (gas) or a solid that becomes a compressible fluid by being heated and pressurized in a supply path supplied to the reaction container 27 or in the reaction container 27. In this case, the gas or solid stored in the tank 21 is heated or pressurized to be in the state (1), (2), or (3) in the phase diagram of FIG. .

  The metering pump 22 supplies the compressive fluid stored in the tank 21 to the reaction vessel 27 at a constant pressure and flow rate. The addition pot 25 stores a catalyst added to the raw material in the reaction vessel 27. The valves (23, 24, 26, 29) open and close each of them, thereby supplying the compressive fluid stored in the tank 21 to the reaction vessel 27 via the addition pot 25 and the addition pot 25. The route for supplying the reaction vessel 27 without going through is switched.

  The reaction vessel 27 contains a monomer and an initiator in advance before starting the polymerization. The reaction vessel 27 is a pressure-resistant vessel for polymerizing the monomer by bringing the monomer and initiator stored in advance, the compressive fluid supplied from the tank 21 and the catalyst supplied from the addition pot 25 into contact with each other. It is. The reaction vessel 27 may be provided with a gas outlet for removing the evaporated material. The reaction vessel 27 has a heater for heating the raw materials and the compressive fluid. Furthermore, the reaction vessel 27 has a stirring device for stirring the raw materials and the compressive fluid. When the density difference between the raw material and the generated polymer occurs, the settling of the generated polymer can be suppressed by adding the stirring of the stirring device, so that the polymerization reaction can proceed more uniformly and quantitatively. The valve 28 is opened after completion of the polymerization reaction to discharge the polymer product P in the reaction vessel 27.

<Continuous polymerization reactor>
Next, the continuous polymerization reaction apparatus 100 will be described with reference to FIG. FIG. 4 is a system diagram showing an example of the polymerization process. In the case where an addition polymerizable monomer having a vinyl group is subjected to living polymerization by a conventional production method, the polymer product is solidified during the reaction, so that the polymer cannot be produced continuously. According to the manufacturing method of this embodiment, for example, a polymer can be continuously manufactured by using the polymerization reaction apparatus 100 shown in FIG.

  In the system diagram of FIG. 4, a polymerization reaction apparatus 100 includes a supply unit 100a that supplies raw materials such as monomers and a compressive fluid, and a polymerization reaction apparatus as an example of a continuous polymerization apparatus that polymerizes the monomer supplied by the supply unit 100a. And a main body 100b. The supply unit 100a has a tank (1, 3, 5, 7, 11), a measuring feeder (2, 4), and a measuring pump (6, 8, 12). The polymerization reaction device main body 100b is connected to the mixing device 9, the liquid feed pump 10, the reaction vessel 13, the metering pump 14, and the other end of the polymerization reaction device main body 100b provided at one end of the polymerization reaction device main body 100b. And an extrusion die 15 provided.

  The tank 1 of the supply unit 100a stores the monomer. The monomer to be stored may be a powder or a molten state. The tank 3 stores solid (powder or granular) of the initiator and the additive. The tank 5 stores a liquid one of the initiator and the additive. The tank 7 stores a compressible fluid. The tank 7 may store a gas (gas) or a solid that becomes a compressible fluid in the course of being supplied to the mixing device 9 or heated or pressurized in the mixing device 9. In this case, the gas or solid stored in the tank 7 is heated or pressurized to be in the state (1), (2), or (3) in the phase diagram of FIG. .

  The metering feeder 2 measures the monomer stored in the tank 1 and continuously supplies it to the mixing device 9. The weighing feeder 4 measures the solid stored in the tank 3 and continuously supplies it to the mixing device 9. The metering pump 6 measures the liquid stored in the tank 5 and continuously supplies it to the mixing device 9. The metering pump 8 continuously supplies the compressive fluid stored in the tank 7 to the mixing device 9 at a constant pressure and flow rate.

  In addition, in this embodiment, supplying continuously is a concept with respect to the method of supplying for every batch, and means supplying so that a polymer may be obtained continuously. That is, as long as a polymer is continuously obtained, each material may be supplied intermittently or intermittently. In addition, when both the initiator and the additive are solid, the polymerization reaction apparatus 100 may not include the tank 5 and the metering pump 6. Similarly, when both the initiator and the additive are liquid, the polymerization reaction apparatus 100 may not include the tank 3 and the metering feeder 4.

  In this embodiment, each apparatus of the polymerization reaction apparatus main body 100b is connected as shown in FIG. 4 by a pressure-resistant piping 30 that transports raw materials, a compressive fluid, or a generated polymer. Moreover, each apparatus of the mixing apparatus 9 of the polymerization reaction apparatus, the liquid feeding pump 10, and the reaction vessel 13 has a tubular member through which the above raw materials and the like pass.

  The mixing device 9 of the polymerization reaction device main body 100b continuously feeds raw materials such as monomers, initiators and additives supplied from the tanks (1, 3, 5) and the compressive fluid supplied from the tank 7. It is an apparatus having a pressure-resistant container for contacting and melting or melting raw materials. In the mixing device 9, the raw material is dissolved or melted by contacting the raw material and the compressive fluid. In the present embodiment, “melting” means a state in which a raw material or a produced polymer comes into contact with a compressive fluid and is plasticized or liquefied while swelling. Further, “dissolving” means that the raw material is dissolved in the compressive fluid.

  When the monomer is dissolved, a fluid phase is formed. When the monomer is melted, a molten phase is formed. In order to proceed the reaction uniformly, either one of the molten phase or the fluid phase is formed in the mixing device 9. It is preferable. Further, in order to advance the reaction in a state where the ratio of raw materials to the compressive fluid is high, it is preferable that the monomer is melted in the mixing device 9. In the present embodiment, by continuously supplying the raw material and the compressive fluid, the raw material such as the monomer and the compressive fluid can be continuously contacted at a constant concentration ratio in the mixing device 9. . Thereby, the raw material can be efficiently dissolved or melted.

  In the present embodiment, since the raw material such as a monomer and the compressive fluid can be continuously contacted at a constant concentration ratio, the raw material can be efficiently melted in the compressive fluid. The shape of the container of the mixing device 9 may be a tank type or a cylindrical shape, but a cylindrical shape in which raw materials are supplied from one end and the mixture is taken out from the other end is preferable. In the container of the mixing device 9, an inlet 9 a for introducing the compressive fluid supplied from the tank 7 by the metering pump 8, an inlet 9 b for introducing the monomer supplied from the tank 1 by the metering feeder 2, and a metering feeder 4 is provided with an inlet 9c for introducing the powder supplied from the tank 3 by 4 and an inlet 9d for introducing the liquid supplied from the tank 5 by the metering pump 6.

  In this embodiment, each introduction port (9a, 9b, 9c, 9d) is comprised by the coupling which connects the container of the mixing apparatus 9, and each piping which conveys each raw material or compressive fluid. This joint is not particularly limited, and known joints such as reducers, couplings, Y, T, and outlets are used. Moreover, the mixing apparatus 9 has a heater for heating each supplied raw material and compressive fluid.

  Furthermore, the mixing device 9 may have a stirring device that stirs the raw materials, the compressive fluid, and the like. When the mixing device 9 has a stirrer, the stirrer includes a uniaxial screw, a biaxial screw meshing with each other, a biaxial mixer having a large number of meshing elements meshing with each other or overlapping each other, and a helical stirring element meshing with each other. A kneader having a static mixer, a static mixer or the like is preferably used. In particular, a biaxial or multiaxial agitation device that meshes with each other is preferable because there is little adhesion of reactants to the agitation device or the container and there is a self-cleaning action.

In the case where the mixing device 9 does not have a stirring device, a pressure-resistant pipe is preferably used as the mixing device 9. In this case, it is possible to reduce the installation space of the polymerization reaction apparatus 100 or improve the layout flexibility by arranging the pressure-resistant piping in a spiral shape or by bending it. In addition, when the mixing apparatus 9 does not have a stirring apparatus, in order to mix each material in the mixing apparatus 9 reliably, it is preferable that the monomer supplied to the mixing apparatus 9 is liquefied beforehand. In addition, when the mixing apparatus 9 does not have a stirring apparatus, in order to mix each material in the mixing apparatus 9 reliably, it is preferable that the monomer supplied to the mixing apparatus 9 is a molten state.

  The liquid feed pump 10 sends each raw material melted by the mixing device 9 to the reaction vessel 13. The tank 11 stores a catalyst. The metering pump 12 measures the catalyst stored in the tank 11 and supplies it to the reaction vessel 13.

  The reaction vessel 13 is a pressure-resistant vessel for polymerizing monomers by mixing each molten raw material fed by the feed pump 10 and the catalyst supplied by the metering pump 12. The shape of the reaction vessel 13 may be a tank type or a cylindrical type, but a cylindrical type with little dead space is preferable. The reaction vessel 13 has an introduction port 13a for introducing each material mixed by the mixing device 9 into the vessel, and an introduction port 13b for introducing the catalyst supplied from the tank 11 by the metering pump 12 into the vessel. Is provided. In this embodiment, each inlet (13a, 13b) is comprised by the coupling which connects the reaction container 13 and each piping which conveys each raw material. This joint is not particularly limited, and known joints such as reducers, couplings, Y, T, and outlets are used.

  Note that the reaction vessel 13 may be provided with a gas outlet for removing evaporated substances. The reaction vessel 13 has a heater for heating the fed raw material. Furthermore, the reaction vessel 13 may have a stirring device that stirs the raw materials, the compressive fluid, and the like. When the reaction vessel 13 has a stirrer, the polymer particles can be prevented from settling due to the difference in density between the raw material and the produced polymer, so that the polymerization reaction can proceed more uniformly and quantitatively. As a stirring device for the reaction vessel 13, a twin screw having a screw that meshes with each other, a stirring element such as a 2-flight (oval) or a 3-flight (triangle-like), a disc or a multi-lobed (clover-shaped) stirring blade. Or the thing of a multi-axis is preferable from a viewpoint of self-cleaning. When the raw material containing the catalyst is sufficiently mixed in advance, a static mixer that performs multi-stage splitting and combining (merging) of the flow with a guide device can also be applied to the stirring device. Examples of the static mixer include those disclosed in Japanese Patent Publication Nos. 47-15526, 47-15527, 47-15528, 47-15533, etc. (multilayered mixer), and the like. Examples disclosed in Japanese Utility Model Laid-Open No. 47-33166 (Kenix type) and similar mixing devices without moving parts can be mentioned and can be included here by reference.

  When the reaction vessel 13 does not have a stirrer, pressure-resistant piping is preferably used as the reaction vessel 13.

  Although FIG. 4 shows an example in which one reaction vessel 13 is provided, two or more reaction vessels 13 can also be used. When a plurality of reaction vessels 13 are used, the reaction (polymerization) conditions for each reaction vessel 13, that is, temperature, catalyst concentration, pressure, average residence time, stirring speed, etc. may be the same. It is preferable to select the optimum conditions. In order to increase the reaction time and complicate the apparatus, it is not a good idea to combine too many containers in multiple stages, and the number of stages is preferably 1 or more and 4 or less, particularly preferably 1 or more and 3 or less.

  The metering pump 14 sends the polymer compound as the polymer product P in the reaction vessel 13 out of the reaction vessel 13 from an extrusion die 15 as an example of a polymer discharge port. In addition, the polymer product P can be sent out from the reaction vessel 13 without using the metering pump 14 by utilizing the pressure difference between the inside and outside of the reaction vessel 13. In this case, in order to adjust the pressure in the reaction vessel 13 and the delivery amount of the polymer product P, a pressure adjusting valve can be used instead of the metering pump 14.

<< Polymerization method >>
Then, the raw material, the compressive fluid, and the polymerization method using the continuous polymerization reactor 100 or the batch polymerization reactor 200 will be described. According to the polymerization method of this embodiment, after the raw material containing an addition polymerizable monomer having a vinyl group applicable to addition polymerization is brought into contact with a compressive fluid, the addition polymerizable monomer having a vinyl group is melted or dissolved. The addition polymerizable monomer having a vinyl group is melt polymerized in the presence of an initiator. As a result, the polymer product does not solidify with the progress of the reaction even if the polymerization is carried out under the reaction conditions below the melting point and softening point of the polymer product, and the shape of the polymer product and the polymer product are removed from the reaction vessel. The advantage is that the degree of freedom is not limited.

  The polymerization reaction temperature (set temperature of the reaction vessel (13, 27)) is not particularly limited, but is usually 120 ° C. or higher and 180 ° C. or lower. Polymerization is preferably carried out without solvent since it is not necessary to remove the solvent.

In the present embodiment, the polymerization reaction time (average residence time in the reaction vessel (13, 27)) is set according to the target molecular weight. When the target molecular weight is 5000 to 1000000, the polymerization reaction time can be, for example, 20 minutes or more and 180 minutes or less.
The average residence time in the present invention refers to the average time required for the reaction product to enter and exit from the polymerization apparatus. In particular, in the case of continuous polymerization, the reaction product is fed to the reaction vessel volume. It is expressed as a ratio of quantities.

In the production method of the present embodiment, the polymerization rate is preferably 60% or more and 95% or less. By being 60% or more, the subsequent demonomer process is not overloaded and the production efficiency is not lowered.
In the present invention, when the viscosity is lowered by the compressed fluid, there is an effect of reducing the apparatus load and increasing the polymerization rate. However, when the polymerization rate is 95% or less, the reaction time does not become too long.
More preferably, the polymerization rate is 70% or more and 90% or less, and more preferably 80% or more and 90% or less for the same reason.

In the production method of the present embodiment, the polymer composition does not limit the present embodiment, but it is preferable to subject the raw material monomer to separation and recovery by subjecting it to a devolatilization treatment or the like.
The amount of residual monomer in the polymer is preferably 2% by mass or less, and preferably 1% by mass or less. If it exceeds 2%, the durability as a polymer material may be insufficient.

<Mixing ratio of monomer and compressive fluid>
The mixing ratio of the monomer and the compressive fluid defined in the present invention is defined by the following formula.
Mixing ratio = mass of raw material / (mass of raw material + mass of compressible fluid)
And in this invention, the value of the said mixing ratio shall be 0.5 or more and 0.9 or less.
If it is less than 0.5, it is not economical due to an increase in the amount of compressive fluid used, and the polymerization rate may decrease because the monomer density decreases. If the mixing ratio is less than 0.5, the mass of the compressive fluid becomes larger than the mass of the raw material, so that the molten phase in which the monomer is melted and the fluid phase in which the monomer is dissolved in the compressive fluid coexist. In some cases, the reaction is difficult to proceed uniformly.
By setting the mixing ratio to 0.5 or more, the reaction proceeds in a state where the concentration of the raw material and the generated polymer (so-called solid content concentration) is high. The solid content concentration in the polymerization system at this time is greatly different from the solid content concentration in the polymerization system when a small amount of monomer is dissolved in an overwhelming amount of compressive fluid in the conventional production method. The production method of this embodiment is characterized in that the polymerization reaction proceeds efficiently and stably even in a polymerization system having a high solid content concentration.
On the other hand, when the mixing ratio exceeds 0.9, the ability of the compressive fluid to melt the monomer may be insufficient, and the intended reaction may not proceed uniformly.

<Reaction pressure>
A preferable reaction pressure of the polymerization reaction in the present invention is preferably 3.7 MPa or more, more preferably 5 MPa or more, and further preferably a critical pressure of 7.4 PMa or more.
Moreover, although there is no restriction | limiting in particular about an upper limit, In order to hold down apparatus cost, Preferably it is 30 Mpa or less, More preferably, it is 20 Mpa or less.

  The weight average molecular weight of the polymer obtained by this embodiment can be adjusted by the amount of the initiator. Although not particularly limited, the weight average molecular weight is generally 30000 or more and can be 300,000 or more. When the weight average molecular weight is less than 30000, the strength as a polymer may be insufficient, which may not be preferable.

  The value (molecular weight distribution: Mw / Mn) obtained by dividing the weight average molecular weight Mw of the polymer compound of the present embodiment by the number average molecular weight Mn is preferably 2 or more.

<< Application of polymer >>
The polymer product obtained by the production method of this embodiment is produced by a production method that does not use an organic solvent. The organic solvent refers to an organic compound that is liquid at normal temperature (25 ° C.) and normal pressure, and is different from a compressive fluid.

  The polymer obtained by the production method of the present embodiment is formed into, for example, particles, films, sheets, molded products, fibers, etc., for example, daily necessities, industrial materials, agricultural products, sanitary materials, pharmaceuticals, cosmetics, electronic Widely used in applications such as photographic toner, packaging materials, electrical equipment materials, home appliance housings, automotive materials.

<< Effects of Embodiment >>
In the conventional radical polymerization of monomers having a vinyl group, when solution polymerization is performed using a solvent, a process for removing the solvent is necessary, and in melt polymerization, a polymer obtained by increasing the viscosity as the reaction proceeds. Productivity is low because the degree of polymerization of the composition is limited. That is, in any conventional method, an increase in the process and an increase in cost due to a decrease in yield are inevitable. According to the polymerization method of this embodiment, by controlling the supply amount of the compressive fluid, it is excellent in terms of low cost, low environmental load, energy saving, resource saving, and excellent in processability and thermal stability. Provision is possible.

Moreover, according to the manufacturing method of this embodiment, there exist the following effects.
(1) The polymerization rate can be increased by reducing the viscosity in the system as compared with the case of polymerizing an addition polymerizable monomer having a vinyl group in a molten state above the melting point by a conventional production method, Production efficiency is increased.
Decreasing the viscosity makes it easier to control the heat generation, and selecting a compressed fluid with less chain movement makes it easy to increase the molecular weight.
(2) In radical polymerization of an addition polymerizable monomer having a vinyl group, the reaction at a relatively low temperature (below the melting point and / or softening point of the polymer to be formed) and at a high concentration (because it becomes a reaction in a bulk state). Therefore, a polymer can be obtained in a short time.
(3) By controlling the temperature and pressure in the polymerization system and controlling the supply amount of the compressive fluid, it is possible to achieve both the polymerization rate and the polymerization efficiency (the ratio of the polymer in the polymerization system).

［２］前記重合反応装置が連続式重合反応装置であり、前記ポリマーを前記連続式重合反応装置から連続的に排出することを特徴とする上記［１］に記載のポリマーの製造方法。
［３］前記圧縮性流体は、二酸化炭素、または炭化水素を含有することを特徴とする上記［１］または［２］に記載のポリマーの製造方法。
［４］前記重合反応装置における重合率が６０％以上９５％以下であり、前記ポリマーの重量平均分子量が３０万以上であることを特徴とする上記［１］乃至［３］のいずれか一項に記載のポリマーの製造方法。
［５］前記ビニル結合を有するモノマーが側鎖にエステル基を有するモノマーであることを特徴とする上記［１］乃至［４］のいずれか一項に記載のポリマーの製造方法。
［６］重合反応装置の反応容器内における平均滞留時間が１５分〜１８０分であることを特徴とする［１］乃至［５］のいずれか一項に記載のポリマーの製造方法。 Moreover, although this invention concerns on the manufacturing method of the polymer of following [1], following [2]-[6] is also included as embodiment.
[1] Using a polymerization reactor, the monomer having a vinyl bond and the compressive fluid were brought into contact with each other at a mixing ratio satisfying the relationship of the following formula (1) to melt or dissolve the monomer having the vinyl bond. A method for producing a polymer, wherein the monomer having a vinyl bond is subjected to addition polymerization in the presence of an initiator, and the obtained polymer is discharged from a polymerization reaction apparatus.

[2] The method for producing a polymer according to [1], wherein the polymerization reaction apparatus is a continuous polymerization reaction apparatus, and the polymer is continuously discharged from the continuous polymerization reaction apparatus.
[3] The method for producing a polymer according to the above [1] or [2], wherein the compressive fluid contains carbon dioxide or hydrocarbon.
[4] The polymerization rate in the polymerization reaction apparatus is 60% or more and 95% or less, and the weight average molecular weight of the polymer is 300,000 or more. A process for producing the polymer described in 1.
[5] The method for producing a polymer according to any one of [1] to [4], wherein the monomer having a vinyl bond is a monomer having an ester group in a side chain.
[6] The method for producing a polymer according to any one of [1] to [5], wherein an average residence time in the reaction vessel of the polymerization reaction apparatus is 15 minutes to 180 minutes.

  Hereinafter, the present embodiment will be described more specifically with reference to examples and comparative examples, but the present invention is not limited to these examples. The molecular weight, molecular weight distribution, and polymerization rate of the polymers obtained in Examples and Comparative Examples were determined as follows.

<Measurement of molecular weight of polymer>
Measurement was performed by GPC (Gel Permeation Chromatography) under the following conditions.
-Equipment: GPC-8020 (manufactured by Tosoh Corporation)
Column: TSK G2000HXL and G4000HXL (manufactured by Tosoh Corporation)
・ Temperature: 40 ℃
・ Solvent: THF (tetrahydrofuran)
Flow rate: 1.0 mL / min 1 mL of a polymer having a concentration of 0.5% by mass is injected, and the number of polymers is calculated using a molecular weight calibration curve prepared by a monodisperse polystyrene standard sample from the molecular weight distribution of the polymer measured under the above conditions. The average molecular weight Mn and the weight average molecular weight Mw were calculated. The molecular weight distribution is a value obtained by dividing Mw by Mn (Mw / Mn).
<Polymerization rate>
The amount of remaining monomer was calculated from the peak area ratio between the polymer and the monomer.
Polymerization rate (%) = polymer area ratio / (polymer area ratio + monomer area ratio) × 100

[Example 1]
Polymerization of methyl methacrylate (MMA) was performed using the polymerization reaction apparatus 200 of FIG.
A 1/4 inch SUS316 pipe was sandwiched between valves (24, 29) and used as the addition pot 25. The addition pot 25 was charged with 0.4 parts by mass of AIBN as a radical initiator and 0.4 parts by mass of n-octyl mercaptan as a chain transfer agent in 2 parts by mass of MMA from which the heavy inhibitor was previously removed.
To the reaction vessel 27, 98 parts by mass of MMA was added.

By operating the metering pump 22 and opening the valves (23, 26), the carbon dioxide stored in the tank 21 was supplied to the reaction vessel 27 without going through the addition pot 25. The temperature in the reaction vessel 27 was 120 ° C., and carbon dioxide was charged until the pressure at that time was 15 MPa. Thereby, methyl methacrylate was brought into contact with carbon dioxide as a compressive fluid to plasticize methyl methacrylate.
Subsequently, the addition pot 25 is pressurized with carbon dioxide, and when reaching the pressure of the reaction vessel 27 (15 MPa) or more, the valves (24, 29) are opened, and the radical initiator and chain transfer agent in the addition pot 25 are opened. Was fed into the reaction vessel 27 to initiate polymerization. After the reaction for 2 hours, the valve 28 was opened, and the polymer product in the reaction vessel 27 was taken out. Table 1 shows the weight average molecular weight, molecular weight distribution, and residual monomer amount obtained by the above-described method for this polymer product (PMMA).

[Examples 2 and 3]
As shown in Table 1-1, the same operation as in Example 1 was performed except that the reaction temperature was changed.
[Examples 4 and 5]
As shown in Table 1-1, the same operation as in Example 1 was performed except that the reaction time was changed.
[Examples 6 and 7]
As shown in Table 1-1, the same operation as in Example 1 was performed except that the reaction pressure was changed.
[Examples 8 and 9]
As shown in Table 1-2, the same operation as in Example 1 was performed except that [monomer / radical initiator] was changed.
[Examples 10 and 11]
As shown in Table 1-2, the same operation as in Example 1 was performed except that the radical initiator type was changed.
[Examples 12 to 14]
As shown in Table 1-2, the same operation as in Example 1 was performed except that the monomer was changed.

Example 15
Polymerization of methyl methacrylate was performed using the polymerization reaction apparatus 100 of FIG. The structure of the polymerization reaction apparatus 100 is shown.
Tank 1, metering feeder 2: Plunger pump NP-S462 made by Nippon Seimitsu Co., Ltd.
The tank 1 was filled with methyl methacrylate (25 ° C.) from which the polymerization inhibitor had been removed in advance.
Tank 3, weighing feeder 4: Not used in this example.
Tank 5, metering pump 6: Not used in this example.
Tank 7: Compressible fluid cylinder
Filled with carbon dioxide.
Tank 11 and metering pump 12: Intelligent HPLC pump (PU-2080) manufactured by JASCO Corporation
The tank 11 was charged with 0.4 parts by mass of AIBN as a radical initiator and 0.4 parts by mass of n-octyl mercaptan as a chain transfer agent in 2 parts by mass of MMA from which the polymerization inhibitor had been removed.
Mixing device 9: Biaxial stirring device with screws that mesh with each other
Cylinder inner diameter 30mm
Cylinder set temperature 150 ℃
2-axis rotation in the same direction
Rotation speed 30rpm
Reaction vessel 13: biaxial kneader
Cylinder inner diameter 40mm
Cylinder set temperature Raw material supply part 150 ℃ Tip part 150 ℃
2-axis rotation in the same direction
Rotation speed 60rpm

  The biaxial agitator of the mixing device 9 and the biaxial kneader of the reaction vessel 13 are operated under the above set conditions. The metering feeder 2 quantitatively supplies the methacrylate in the tank 1 into the container of the biaxial stirring device. The metering pump 8 supplies carbon dioxide as a compressive fluid from the tank 7 so that the pressure in the container of the biaxial stirring device is 15 MPa. Thus, 10% by mass of compressible fluid is continuously brought into contact with and mixed with 100% by mass of methyl methacrylate supplied from each tank (1, 7) by the screw of the biaxial agitator, and each raw material Dissolve.

  The methyl methacrylate prepared in advance by the mixing device 9 is fed to the reaction vessel 13 by the liquid feed pump 10. The metering pump 12 supplied AIBN as a polymerization catalyst in the tank 11 to the raw material supply hole of the biaxial kneader as the reaction vessel 13 so as to be 0.50 mol% with respect to methyl methacrylate, and polymerized methyl methacrylate. In this case, the average residence time of each raw material in the twin-screw kneader was about 3600 seconds (60 minutes), and this was taken as the reaction time. A metering pump 14 and an extrusion cap 15 are attached to the tip of the biaxial kneader. The feed rate of the polymer (PMMA) as the product of the metering pump 14 is 70 g / min. The resulting polymer product solidifies after removal. The physical properties of the obtained polymer product were determined by the above method. The results are shown in Table 1-3.

[Examples 16-17]
The same operation as in Example 15 was performed except that the flow rate of CO ₂ was changed as shown in the table. The results are shown in Table 1-3.

Abbreviations in the monomers, radical initiators, and chain transfer agents in Table 1-1 to Table 1-3 are as follows.
OM: n-octyl mercaptan Luperox 575:
t-Amylperoxy-2-ethylhexanoate (Arkema Yoshitomi)
Luperox 531: 1,1-di (t-butylperoxy) cyclohexane
1,1-di (t-amylperoxy) cyclohexane
1,1-di (t-butylperoxy) cyclohexane 331
MMA: Methyl methacrylate MA: Methyl acrylate EA: Ethyl acrylate

1, 3, 5, 7, 11 Tank 2, 4 Metering feeder 6, 8, 12, 14 Metering pump 9 Mixing device 9a, 9b, 9c, 9d Inlet 10 Feed pump 13 Reaction vessel 13a, 13b Inlet 15 Push Outlet gold 21 Tank 22 Metering pump 25 Addition pot 27 Reaction vessel 23, 24, 26, 28, 29 Valve 30 Pipe 30a, 30b Joint 100 Polymerization reaction apparatus 100a Supply unit 100b Polymerization reaction apparatus body 200 Polymerization reaction apparatus

JP 54-149788 A Japanese Patent Laid-Open No. 3-111408 JP 2006-188612 A

Claims (6)

Using a polymerization reactor, the monomer having a vinyl bond and the compressive fluid are brought into contact at a mixing ratio satisfying the relationship of the following formula (1) to melt or dissolve the monomer having the vinyl bond. A method for producing a polymer, comprising subjecting a monomer having a vinyl bond to addition polymerization in the presence of an agent, and discharging the obtained polymer from a polymerization reactor.

  The method for producing a polymer according to claim 1, wherein the polymerization reaction apparatus is a continuous polymerization reaction apparatus, and the polymer is continuously discharged from the continuous polymerization reaction apparatus.   The method for producing a polymer according to claim 1, wherein the compressive fluid contains carbon dioxide or hydrocarbon.   The polymer production according to any one of claims 1 to 3, wherein a polymerization rate in the polymerization reaction apparatus is 60% or more and 95% or less, and a weight average molecular weight of the polymer is 300,000 or more. Method.   The method for producing a polymer according to any one of claims 1 to 4, wherein the monomer having a vinyl bond is a monomer having an ester group in a side chain.   The method for producing a polymer according to any one of claims 1 to 5, wherein an average residence time in the reaction vessel of the polymerization reactor is 15 minutes to 180 minutes.

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