JPH0134444B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus for continuously producing a polymer.

Emulsion polymerization, suspension polymerization, solution polymerization, and bulk polymerization are known methods for producing polymers, but these polymerization methods have slightly different properties of the resulting polymers, so they are difficult to manufacture. They are selected and adopted as appropriate depending on the target polymer. When viewed as a polymerization reaction process, a continuous bulk polymerization method is pointed out as a preferable method because it saves resources and energy, and can solve the problem of pollution by making it a closed process. However, at present, in continuous bulk polymerization, instability of the polymerization system,
There remains a need to solve various problems related to the viscosity, which increases with the progress of polymerization, and the heat removal area, which decreases relative to the reaction volume as the scale increases.

Generally, in bulk polymerization, the viscosity within the reaction system increases exponentially as the polymerization reaction progresses. In such a case, a so-called abnormal stagnation part, which does not move forever, tends to grow in a certain part of the reaction system. Since this abnormal retention area remains at high temperature for a long time, the polymer produced in this area is likely to deteriorate or gel, and if this is mixed into normal polymer, the quality of the produced polymer will be significantly impaired.

Various methods have been proposed in the past to eliminate such abnormal retention areas. One of these methods is to terminate the polymerization in a state where the viscosity of the polymerization solution is low without increasing the final polymerization rate, or to carry out the polymerization by mixing a certain amount of solvent. According to this method, the viscosity of the polymerization liquid to be handled becomes low, so that abnormal stagnation areas are less likely to occur, but there is a drawback that the operating rate of the apparatus decreases.

Another method is to use a screw-type stirring blade or the like that can apply shear to the polymerization liquid and increase the shear rate of the liquid near the wall of the reaction vessel as much as possible. However, in this case, not only is a significant amount of power consumed, but the heat of stirring results in an increase in the temperature within the system. Further, depending on the polymer, the physical properties of the product obtained may deteriorate when subjected to strong shearing.

Generally, continuous polymerization apparatuses include a complete mixing tank reactor, which is a differential reactor, and a tube or tower reactor, which is an integral reactor. When carrying out continuous bulk polymerization using a complete mixing tank reactor, it is necessary to make the inside of the reaction system uniform, so vigorous stirring is required in a highly viscous liquid, and the above-mentioned power consumption is required. As the amount increases, the polymerization liquid becomes more susceptible to shear, and the residence time distribution of the liquid within the reaction system becomes wider. On the other hand, when carrying out continuous bulk polymerization using a tubular or tower reactor, if measures can be taken to prevent abnormal stagnation, it is not necessary to make the entire reaction system homogeneous, so there is no need to stir as vigorously. , and the residence time distribution of the liquid in the system is extremely narrow and close to piston flow, so
Such a tube-type or column-type reactor can be said to be a reactor suitable for continuous bulk polymerization.

However, conventionally used tubular or tower reactors have problems such as the presence of abnormal stagnation, piston flow characteristics, and equipment manufacturing. For example, in the case of using a tower reactor as described in JP-A-53-99290, there are no problems in terms of the existence of abnormal stagnation parts and equipment fabrication, but the piston flow is poor and the residence time distribution is narrow. It can not be said.

In view of this situation, the present inventors conducted intensive research to develop a column-type reactor suitable for continuous bulk polymerization that does not produce abnormal retention areas, has a narrow residence time distribution, and is easy to manufacture, and as a result, the present invention was achieved. This is what I did.

That is, the present invention provides a cylindrical reaction vessel having a structure elongated in the flow direction of the liquid and provided with a liquid inlet and a liquid outlet, a rotating shaft attached to the inside of the reaction vessel, and a
or more side feed nozzles, and a plurality of double helical band type stirring blades are arranged on the rotating shaft so that most of them face the same direction, and the stirring blades are connected to each other. One or more baffle plates having a partitioning effect are provided between the side feed nozzles, and the side feed nozzle is partitioned by the baffle plates, and the mixing chamber does not have the double-helix type stirring blades therein. This continuous bulk polymerization apparatus is characterized in that it is attached facing the.

Monomers that can be bulk polymerized in the continuous polymerization apparatus of the present invention include styrene, α-methylstyrene, styrene in which the benzene ring is substituted with alkyl,
For example, O-, m-, P-methylstyrene, O-,
m-, P-ethylvinylbenzene and styrene in which the benzene ring is halogenated, such as O-, m-,
Examples include alkenyl aromatic compounds such as p-chlor or bromstyrene. These can be used alone or in mixtures as monomers. Further, copolymerizable monomers such as acrylonitrile and methacrylic acid esters may be added to these alkenyl aromatic monomers. Furthermore, rubber-like polymers such as polybutadiene, copolymers of butadiene and styrene, acrylonitrile, methyl methacrylate, natural rubber, polychloroprene, ethylene-propylene copolymers, ethylene-propylene-diene monomer copolymers, etc. Solutions in one or more of the monomers can also be used.

Monomers that can be subjected to bulk polymerization reactions in the continuous polymerization apparatus of the present invention are as described above, but they can also be applied to those that cause addition polymerization reactions and those that cause condensation polymerization reactions such as nylon and polyester. obtain. The term "bulk polymerization" as used herein also includes solution polymerization using 30% by weight or less of a solvent.

Polymerization can be initiated thermally or by known initiators that release free radicals upon decomposition, such as azo compounds such as azobisisobutyronitrile or peroxides such as benzoyl peroxide. Then you can start.

An example of a continuous bulk polymerization apparatus according to the present invention is shown in FIGS. 1 and 3, and the effects of the present invention will be explained with reference to FIG.

In the figure, reference numeral 1 denotes a cylindrical polymerization reaction vessel that is long in the direction of flow of the liquid, and is equipped with a jacket 2, which allows heating, heat retention, or cooling as appropriate. The jacket may be one, or may be divided into several pieces. 12,13
are the inlet and outlet of the heating medium. Reference numeral 3 denotes a rotating shaft, and a double helical band type stirring blade 4, baffle plates 5, 8, and an auxiliary stirring blade 7 are attached to this rotating shaft.

The interior of the reaction vessel is partitioned by a baffle plate into a mixing chamber 6 for mixing the side feed liquid, each cell containing one double helical band type stirring blade and one auxiliary stirring blade. 9 and 10 are the main feed liquid inlet and outlet. A side feed nozzle 11 is attached facing the mixing chamber, and the side feed liquid coming out of the nozzle is mixed with the main feed liquid in the mixing chamber.

The stirring blades in each cell are all attached in the same direction, and the rotation of the blades makes the liquid flow state in each cell almost the same. Note that the circulation flow indicated by the arrow in the stirring blade portion in the figure is the partial flow direction of the liquid. The direction of rotation can be either direction, but preferably, as shown in Figure 1 or Figure 4, when the blades rotate, the flow of liquid near the wall of the reaction vessel is opposite to the direction of flow of liquid throughout the reaction vessel. It is better to rotate it accordingly. If the reaction vessel is rotated so that the flow of the liquid near the wall surface is the same as the flow direction of the liquid throughout the reaction vessel, short passes of the liquid are likely to occur even if a baffle plate is present, and the piston flow properties will deteriorate.

It is preferable that all stirring blades in each cell are oriented in the same direction, and it is desirable that at least 80% or more of the stirring blades are oriented in the same direction. For example, Tokukai Akira
53-99290, if the stirring blades are installed in alternating or irregular orientations, the movement of liquid between each cell will be hindered to some extent, resulting in uniformity throughout the reactor. Although this is not the case, the residence time distribution becomes wider than when they are attached in substantially the same direction, and this cannot be adopted from the perspective of the purpose of the present invention.

FIG. 2 shows a residence time distribution curve measured using the apparatus shown in FIG. 1 to examine the piston flow properties of fluid. θ is time, is average residence time, and ψ=θ/
θ is a dimensionless time, and E(ψ) is a residence time distribution function. In the figure, curve A is the residence time distribution curve when the stirring blades are all attached in the same direction, and curve B is the residence time distribution curve when the stirring blades are attached in alternate directions.
Compared to curve B, curve A has a narrower residence time distribution;
Improved piston flow. Curve C is 8
This is a residence time distribution curve when only one of the stirring blades is attached in a different direction, and is almost the same as curve A.

The stirring blades of the apparatus of the present invention are preferably half-pitch double helical band blades, but other double helical band blades such as one-pitch double helical band blades may also be used. Alternatively, a screw or the like may be combined with the double helical band blade.

FIG. 3 shows a schematic diagram of the double helical band stirring blade and the mixing chamber for mixing the side feed liquid used in the continuous bulk polymerization apparatus of the present invention.

Regarding the blade width b of the double helical band stirring blade, its ratio to the inner diameter D of the reaction vessel is 0.05≦b/D≦
It is preferable to use one that satisfies the relationship of 0.3. If b/D is smaller than 0.05, the amount of liquid sent out by the blades is small, which causes abnormal stagnation. On the other hand, if b/D is larger than 0.3, the amount of liquid sent out by the blades is too large and each cell This is undesirable because the movement of the liquid between the stirring blades increases, making it impossible to obtain a narrow residence time distribution, and at the same time, the power required to rotate the stirring blades increases.

The outer diameter d of the double helical band type stirring blade is preferably set so that the clearance (δ=D−d/2) with the inner wall of the reaction vessel satisfies 1 mm<δ<30 mm. δ
If δ is less than 1 mm, it is undesirable because it is extremely difficult to manufacture the device and contact between the stirring blade and the reaction vessel may occur, and if δ is more than 30 mm, abnormal stagnation may occur near the walls of the reaction vessel. This is not desirable because it causes

The axial length h of the double helical band stirring blade is h/L relative to the axial length L of the cell with each stirring blade.
It is preferable that it is ≧0.5. If h/L is less than 0.5, the space between the stirring blade and the baffle plate becomes wide, which is not preferable because it causes an abnormal stagnation part to occur there.

There is no particular restriction on the rotation speed of the stirring blade when producing a polymer using the apparatus of the present invention, and it is 1 rpm.
If it is above, there is an effect of preventing abnormal retention near the inner wall of the reaction vessel. However, if the rpm is higher than 30 rpm, the movement of liquid between each cell will be rapid, making it impossible to obtain a narrow residence time distribution, and the power required for stirring will increase.
Generally undesirable.

In the device of the present invention, free movement of liquid between each cell is prevented only by the presence of a baffle plate having a partitioning effect between the stirring blades.
A narrow residence time distribution similar to that of a piston flow can be obtained, and if there is no baffle plate that has a partitioning effect, the flow of liquid in the reaction vessel will not be separated in each cell and will be uniform throughout the reaction vessel, resulting in an extremely short residence time distribution. The distribution is wide. Curve D in Figure 2 shows the residence time distribution curve in the apparatus shown in Figure 1 when all the stirring blades are installed in the same direction but no baffle plates are attached. An extremely wide distribution of similar residence times was obtained.

Regarding the baffle plate having a partitioning effect and provided between the stirring blades, the opening area ratio thereof is preferably in the range of 5 to 40%, preferably 7 to 30%. If an opening area ratio of less than 5% is used, it is undesirable because the polymer will adhere to the baffle plate as the viscosity of the polymerization solution increases;
If more than 200 ml of liquid is used, the movement of liquid between adjacent cells will increase and the partitioning effect will be lost.

The opening area ratio here refers to the sum of the area of the openings on the baffle plate and the area of the clearance between the baffle plate and the inner wall of the reaction vessel, relative to the cross-sectional area of the polymerization reaction vessel perpendicular to the rotation axis. It is a value expressed as a ratio. However, when using a multi-tubular heat exchanger as a baffle plate, the opening area ratio is the sum of the area of the opening on the baffle plate and the area of the clearance between the baffle plate and the rotating shaft. It is expressed as a ratio to the cross-sectional area of the reaction vessel perpendicular to .

As the baffle plate having a partitioning effect, a baffle plate of a disc-shaped perforated plate having the above-mentioned opening area ratio that rotates with the shaft is suitable, but the baffle plate is not particularly limited thereto. For example, other baffles include shell-and-tube heat exchangers or other heat exchangers having the above-mentioned opening area ratio. When using these heat exchangers, if the opening area ratio is kept within the above range, it is possible to have a partitioning effect, and at the same time, a large amount of polymerization heat generated when monomers are polymerized can be removed, and the polymerization equipment This also solves the problem of removing polymerization heat when scaled up.

FIG. 4 shows an example of a continuous bulk polymerization apparatus in which a disk-shaped perforated plate rotating with the aforementioned shaft and a multi-tubular heat exchanger are simultaneously used as baffles having a partitioning effect. Reference numeral 1 denotes a cylindrical polymerization reaction vessel that is long in the flow direction of the liquid, and two of them are stacked on top of each other at a flange 18 for use. In this device, a rotating disc-shaped perforated plate 5 and a multi-tubular heat exchanger 17 are used as baffle plates having a partitioning effect. The multi-tubular heat exchanger 17 has a partitioning effect and at the same time,
Polymerization heat can also be removed by flowing a heat medium from 12 to 13. That is, in this apparatus, the jacket 2 and the shell-and-tube heat exchanger 17 can remove the polymerization heat. When the equipment is scaled up, jacket 2 alone will not be sufficient to remove the polymerization heat, but
The insufficient polymerization heat removal area can be solved by appropriately adjusting the size of the multi-tubular heat exchanger 17.

The mixing chamber 6 in which the side feed liquid is mixed with the main feed liquid is separated from other cells by a baffle plate having a partitioning effect, and includes a side feed nozzle 11 and one or two auxiliary stirring blades 7.
is attached.

Since the primary role of the side feed nozzle is as a supply port for the side feed liquid, its shape is not particularly limited. For example, it may be a simple circular tube, but the tip of the nozzle is lower than the inner wall of the reaction vessel. Preferably, it protrudes inward. When the tip of the side feed nozzle is at the same position as or near the inner wall of the reaction vessel, if the viscosity or density of the side feed liquid and the main feed liquid are different, the side feed liquid may be mixed with the main feed liquid in the mixing chamber before the reaction vessel This is undesirable because it exits the mixing chamber along the inner wall. As the baffle plate that separates the mixing chamber for mixing the side feed liquid from other cells, a baffle plate similar to the baffle plate described above is used.

Regarding the size of the mixing chamber in which the side feed liquid is mixed, the ratio of its axial length l to the axial length L of the cell with double helical band stirring blades is l/L≦0.5. It is preferable to have one. l/L>
In the case of 0.5, there is no problem if the side feed liquid is sufficiently mixed in the mixing chamber and the liquid in the mixing chamber is uniform.
As the mixing chamber becomes larger, it is necessary to use strong stirring to achieve uniformity, which requires more power for stirring.
Undesirable.

It is preferable to install an auxiliary stirring blade in the mixing chamber where the side feed liquid is mixed, and as the auxiliary stirring blade, it is necessary to improve the mixing in the direction perpendicular to the axis, so it is necessary to use a plurality of blades, for example, four blades. Alternatively, eight patru wings are suitable. As shown in Figure 4, it is best to install the auxiliary stirring blades immediately downstream of the main feed liquid in the flow direction of the side feed nozzle, but it is also possible to install them at two locations across the side feed nozzle. . There is no particular restriction on the size of the auxiliary stirring blade, but in the case of paddle blades, the blade length d′ is preferably such that the blade tip is closer to the inner wall of the reaction vessel than the tip of the side feed nozzle. The clearance between the stirring blade and the inner wall of the reaction vessel is preferably set to be approximately the same as the above-mentioned clearance δ between the double helical band stirring blade and the inner wall of the reaction vessel. In addition, the larger the blade width b' of the auxiliary stirring blade is, the better; b'/l ≥
1/3 is preferable.

A side feed liquid such as a monomer, a solvent, or various additives can be continuously injected from the side feed nozzle, but it is not necessarily necessary to inject the side feed liquid from there. Even if no side feed liquid is injected, the presence of the side feed nozzle and the mixing chamber does not impair the features of the polymerization apparatus according to the invention.

When performing continuous polymerization using the continuous bulk polymerization apparatus according to the present invention, the viscosity of the polymerization solution is 1 poise to 1 poise.
30000 poise is appropriate. There is no need to use this device for low-viscosity polymerization liquids of 1 poise or less, but for high-viscosity polymerization liquids of 30,000 poise or more, there are problems such as increased stirring power and the occurrence of abnormal stagnation. Even when using this device, measures other than those according to the present invention are required.

By using the device of the present invention as described above, for the first time, no abnormal stagnation occurs and with less power,
A continuous bulk polymerization with a very narrow residence time distribution close to the piston flow is carried out. At the same time, this device is extremely simple to manufacture in that double helical band blades and the like used in general industrial equipment can be used as they are.

In addition, compared to a complete mixing tank type continuous bulk polymerization device, this device requires less rotation speed of the stirring blade, so it does not require as much power, and it can be operated in a state where the polymerization liquid has a high viscosity. This makes it possible to reduce the amount of polymerization or increase the final polymerization rate, resulting in an efficient polymer production process.

Furthermore, the device can be used either horizontally or vertically.

From these points, the present invention is extremely versatile and is not limited to the limited illustrations in the specification, and any device that satisfies the contents described in the claims is included in the present invention. It is.

Examples are shown below.

Example 1 95% by weight styrene monomer, 5% by weight commercially available polybutadiene (e.g. Diene 55 from Asahi Kasei)
After mixing and dissolving the monomer composition, the mixture was continuously fed at 3.0/Hr into a 3.0 complete mixing tank reactor equipped with a screw and a draft tube, and prepolymerization was carried out at 135°C. . This polymerization liquid was continuously taken out from the reactor and continuously supplied to the main polymerization reactor for subsequent polymerization.

As the main polymerization reactor, the cylindrical reactor of the present invention shown in FIG. 1 was used. This reactor has an inner diameter of 10
A cylindrical reactor with a length of 40 cm and a jacket and a liquid inlet and outlet. This reaction vessel has a rotating shaft in the center, and on the rotating shaft are eight half-pitch double helical band stirring blades, and between the stirring blades are disc-shaped porous holes that rotate with the shaft. A plate is attached to divide the inside of the reaction vessel into eight cells. Further, this reaction vessel is provided with a mixing chamber for mixing the side feed liquid between the fourth cell and the fifth cell, and a side feed nozzle is installed facing the mixing chamber. The double helical band stirring blade has a blade width of 2cm, a blade shaft length of 4cm, and an outer diameter of the blade.
A 9.5 cm one was used, and the clearance between the inner wall of the reaction vessel and the stirring blade was 2.5 mm. The direction of the stirring blade is
All are in the same direction, and the direction of rotation is such that the liquid flows as shown in FIG. The disc-shaped perforated plate has a diameter
The size is 9.5 cm and 2 mm thick, and a total of 24 holes with a diameter of 4 mm are opened in 8 directions radially around the shaft (opening area ratio 14%).The mixing chamber for mixing the side feed liquid is the aforementioned disk. It is separated from other cells by a baffle plate that rotates with a shaft of the same type as the perforated plate.
Its length in the rotation axis direction is 2 cm. Inside the mixing chamber, a side feed nozzle with an outer diameter of 6 mm and its tip protruding 2 cm inward from the inner wall of the polymerization reaction vessel, and one auxiliary stirring blade consisting of four pawl blades with a blade length of 9.5 cm and a blade width of 8 mm are installed. has been done. Three such reactors were connected in series to carry out the main polymerization reaction.

The prepolymerized polymer solution described above was continuously supplied to the first main polymerization reactor and heated to 130°C through a jacket.
Polymerization was carried out by heating at 10 rpm and stirring at 10 rpm. Further, a mixture of ethylbenzene and white mineral oil in a ratio of 2:1 as a solvent and an additive was continuously fed at a rate of 0.2/hr from the side feed nozzle of the first main polymerization reactor and mixed in the mixing chamber. The polymerization liquid polymerized in the first main polymerization reactor was then supplied to the second main polymerization reactor. In the second main polymerization reactor, the jacket was heated to 135°C and stirred at 10 rpm, and at the same time, a 2:1 mixture of ethylbenzene and white mineral oil was continuously fed from a side feed nozzle as a solvent and an additive at a rate of 0.1/hr. The mixture was mixed in a mixing chamber to carry out polymerization. Furthermore, the polymerization liquid was continuously supplied to the third main polymerization reactor. In the third main polymerization reactor, the jacket was heated to 155°C and the polymerization was completed with stirring at 5 rpm. No side feed was performed from the side feed nozzle of the third main polymerization reactor.

The monomer conversion rate in the polymerization liquid exiting the third main polymerization reactor was 86% by weight. The temperature of the polymerization solution was 165°C.

The polymerization liquid continuously discharged from the third main polymerization reactor is subjected to a conventionally known devolatilization method to remove unreacted monomers and solvents, and then pelletized using an extruder to improve impact resistance. A polystyrene product was obtained.

The final product thus obtained exhibits the following properties.

Rubber content 5.8% by weight Intrinsic viscosity of the soft phase 0.74 (measured in toluene at 30°C) Melt flow index (190°C)
0.91g/10min Izot impact strength 9.5Kg・cm/cm (with notch) Tensile strength 240Kg/cm Tensile elongation 64% Example 2 This example uses the shell-and-tube heat exchanger shown in Figure 4 as the main polymerization reactor. The experiment was carried out using the reactor of the present invention equipped with a reactor, and the experiment was carried out under the same conditions as in Example 1 except for the following points.

a. Use 20 complete mixing tank reactors for prepolymerization.

b. A monomer composition in which polybutadiene rubber is dissolved is supplied at a rate of 20/Hr.

c. Flow a 120°C heat medium through the jacket and heat exchanger of the first main polymerization reactor. (Rotation speed: 10 rpm) d. Flow a heat medium at 130°C through the jacket and heat exchanger of the second main polymerization reactor. (Rotation speed is 10 rpm) e. Flow a heat medium at 150°C through the jacket and heat exchanger of the third main polymerization reactor. (Rotation speed: 5 rpm) f A 2:1 mixture of ethylbenzene and white mineral oil was added at a rate of 2.0/2 from the side feed nozzles of the first and second main polymerization reactors, respectively.
Supply and mix at a rate of 1.0/Hr.

The following main polymerization reactor was used.

The total length of the reaction vessel is 80 cm, and the inner wall is 20 cm in cell section.
cm, and are divided into two parts that are stacked on top of each other. This reaction vessel had a rotating shaft in the center, and six half-pitch double helical band stirring blades were attached to the rotating shaft. The entire reactor is divided into six cells and one mixing chamber by a disk-shaped perforated plate rotating with four shafts and two shell-and-tube heat exchangers. The mixing chamber is provided in front of the third cell. The double helical band stirring blade used had a blade width of 2 cm, a blade axis length of 7 cm, and an outer diameter of 19.5 cm, and the clearance with the inner wall of the reaction vessel was 2.5 mm. The stirring blades are all oriented in the same direction, and the direction of rotation is such that the liquid flows as shown in FIG. The disc-shaped perforated plate has a diameter of 19.5 cm and a thickness of 2 mm.
There are 18 1.4cm holes in an equilateral triangular arrangement (opening area ratio: 14%). For shell-and-tube heat exchangers, 18 tubes with an inner diameter of 1.4 cm and a length of 10 cm are arranged in an equilateral triangle.
Use a shell-and-tube type with a book and a tube with an inner diameter of 4 cm and a length of 10 cm in the center (opening area ratio: 11%). The length of the mixing chamber in the direction of the rotation axis is
It is 3.5 cm in size, and there is one side feed nozzle with an outer diameter of 6 mm and whose tip protrudes 5 cm inward from the inner wall of the reaction vessel, and one auxiliary stirring blade of four paddle blades with a blade length of 19.5 cm and a blade width of 2 cm. is set up.

When carried out under these conditions, the final product obtained was almost the same as in Example 1.

Reference Example 1 Same conditions as Example 1, but continuous polymerization using a 9.0 cm diameter disc with 6 3 cm diameter holes (opening area ratio 73%) instead of the disc-shaped perforated plate in the main polymerization reactor. Polymerization was carried out.

As a result, the temperature distribution within the reaction vessel was disturbed, and the structure and physical properties of the resin were unstable and inferior to those of Example 1.

Comparative Example 1 Same conditions as Example 1, but with a blade width of 3 cm and a blade length instead of the double helical band type stirring blade in the main polymerization reactor.
Continuous polymerization was carried out using four 9.5 cm paddle-type stirring blades.

As a result, a high-temperature region was generated in the reaction tank, making it impossible to operate in a stable state.

[Brief explanation of drawings]

1 and 4 are schematic diagrams of a continuous bulk polymerization apparatus according to the present invention. 1: Polymerization reaction vessel, 2: Jacket, 3: Rotating shaft, 4: Stirring blade, 5: Baffle plate, 6: Mixing chamber for mixing side feed liquid, 7: Auxiliary stirring blade for mixing chamber,
8: Baffle plate, 9: Liquid inlet, 10: Liquid outlet, 1
1: Side feed nozzle, 12: Heat medium inlet, 1
3: Heat medium outlet, 14: Main feed liquid inflow direction, 15: Main feed liquid outflow direction, 16: Side feed liquid inflow direction, 17: Multi-tube heat exchanger, 18: Flange Figure 2 shows the device shown in Figure 1. These are residence time distribution curves measured with various specifications. FIG. 3 is a schematic diagram of a double helical band type stirring blade used in the continuous bulk polymerization apparatus of the present invention. D: inner wall of polymerization reaction vessel, b: blade width of stirring blade,
d: outer diameter of the stirring blade, δ: clearance between the inner wall of the polymerization reaction vessel and the outer periphery of the stirring blade, h: axial length of the stirring blade,
L: Length of the cell with stirring blades in the direction of the rotation axis, b′:
Blade width of the auxiliary stirring blade, d′: Blade length of the auxiliary stirring blade, l:
The length of the mixing chamber in the direction of the rotation axis.

Claims (1)

[Scope of Claims] 1. A cylindrical reaction vessel having a structure elongated in the flow direction of the liquid and having a liquid inlet and a liquid outlet, a rotating shaft attached to the inside of the reaction vessel, and one or more side walls. A plurality of double helical band type stirring blades are arranged on the rotating shaft so that most of them face the same direction, and a partition effect is created between the stirring blades. one or more baffle plates are attached thereto, and the side feed nozzle is attached facing a mixing chamber that is partitioned by the baffle plates and does not have the double helical stirring blades therein. A continuous bulk polymerization device characterized by: 2. The apparatus according to claim 1, wherein the ratio of the blade width b of the double helical band stirring blade to the inner diameter D of the reaction vessel is 0.05≦b/D≦0.3. 3 The clearance δ between the inner wall of the reaction vessel and the outer periphery of the double helical band stirring blade is 1 mm<δ<
3. The device according to claim 1 or 2, which has a diameter of 30 mm. 4 The ratio of the axial length h of the double helical band type stirring blade to the length L in the rotational axis direction of the cell divided by the baffle plate and having the double helical band type stirring blade inside thereof is h. The device according to claim 1, 2 or 3, wherein /L≧0.5. 5. The apparatus according to claim 1, 2, 3, or 4, wherein the opening area ratio of the baffle plate to the cross-sectional area of the reaction vessel is in the range of 5 to 40%. 6 Claims 1, 2, and 2, wherein one or two auxiliary stirring blades are attached to the rotating shaft in the mixing chamber.
The device according to item 3, 4 or 5. 7. Claim 1, wherein the tip of the side feed nozzle protrudes from the inner wall of the reaction vessel.
The device according to item 2, 3, 4, 5 or 6. 8. The device according to claim 4, 5, 6, or 7, wherein the length l of the mixing chamber in the direction of the rotational axis is l/L≦0.5 with respect to the length L. 9. The device according to claim 6, 7 or 8, wherein the auxiliary stirring blades are a plurality of paddle blades.