JPS58147332A - Devolatilization extruding method and device thereof - Google Patents

Abstract

PURPOSE:To efficiently separate and remove a volatile component from a polymerization reaction product, by using a devolatilization extruder which is constituted such that a rotor is built in a stator, and a gap formed with the two parts is brought to a vacuum or a pressurized condition. CONSTITUTION:A polymer composition containing a volatile component, such as unreacted monomers, solvents, is introduced in a gap part 6, which is formed by an inner surface 3 of a stator and an outer surface 7 of a rotor 8 and is held under a vacuum state of about 5 Torr or a pressurizing state of about 2 atmosphere, in a devolatilization extruder through an inlet 1 and a pore 5 (a numeral 4 is a needle valve, and 2 is a stator). A volatile matter separated by a gap part 6 is led out for collection through an outlet 12 for volatile matter formed in an outer peripheral direction of a rotation surface, meanwhile, a polymer composition is conveyed to the right upper of a drawing by a discharge force produced as a result of the rotation of the rotor 8, and is removed from an outlet 14 of an extruder die 13.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a method for continuously separating volatile components such as unreacted monomers, solvents, by-products, or impurities from a thermoplastic polymer composition containing these volatile components. related. The technique of continuously devolatilizing a polymer composition containing a large amount of volatile components (25% by weight or more), extruding the polymer composition, and recovering the volatile components is based on the lump heavy metal method or the one-component polymerization method. This technique is extremely important both in the production of thermoplastic polymer compositions in the form of thermoplastic or rubber-like substances, and in the case where the purpose is to recover volatile components themselves. - When producing a thermoplastic polymer composition by a bulk polymerization method or a solution polymerization method, if the polymer content in the liquid polymer composition is increased, the viscosity of the polymerization system becomes very high, and the polymerization Because the amount of heat generated by the reaction increases, in a regular continuous polymerization reactor and (in a stirred tank reactor), the polymer content is generally 70% by weight or more, although it depends on the polymerization degree of the polymer and the polymerization reaction temperature conditions. Therefore, K, which has a polymer content of 70% by weight or more, requires a reaction device with a special stirring function and a large heat transfer area, but these devices are expensive. Even if this is used, if the polymer content exceeds 75% by weight, the stirring power and shear calorific value due to stirring will increase, making it impractical.In other words, unreacted monomers in the polymer composition, Volatile acids such as solvents and by-products.

It is difficult to reduce the combined amount to 25% by weight or less. On the other hand, setting the polymer content to less than 10% by weight is advantageous in that the polymerization system has a low viscosity and the reaction can be easily controlled, but it also volatilizes unreacted polymers, solvents, by-products, etc. It is not normally carried out because the conditions for this process are harsh and at the same time the amount of circulation increases, requiring large equipment and increasing energy consumption, which is industrially disadvantageous. However, when producing diene polymers or copolymers that tend to form crosslinked structures and gel when polymerized to a high polymer content, or when the purpose is to recover solvents, etc.
The devolatilization of polymer compositions with a low polymer content of 10% by weight is also of great industrial value.

As a basic method for removing volatile components from a polymer composition, a method is known in which the polymer composition is heated to a high temperature and then introduced into a vacuum atmosphere to be volatilized and separated. If the volatile components are less than 10% by weight, they can be separated using a so-called pent extruder.

However, when removing volatile components from polymer compositions containing large amounts of unreacted monomer, solvent content, and/or by-products of 25 to 99.9 wt. There are some problems. The first is that it is difficult to heat the polymer composition to provide the necessary amount of heat for volatilization, and the second is that the apparent volume increases due to foaming when volatilized in a vacuum or atmospheric pressure. The increase in viscosity makes handling such as transfer and heating of the polymer composition difficult, and the surface solidifies upon cooling, inhibiting the progress of volatilization. Third, side reactions such as decomposition under high temperature, high pressure, or vacuum conditions may produce various by-products or color the resulting polymer composition and/or the volatile components recovered. This results in quality deterioration, which is directly affected by residence time.
It is necessary to avoid local stagnation, which can occur especially at high temperatures, and to shorten the processing time as much as possible.

An object of the present invention is to provide an excellent method for solving these technical problems all at once.

Stirring tanks, kneading machines, and submerged thin film towers, which are commonly used as methods for evaporating and separating volatile components from mixed solutions containing volatile components, are critical when used for devolatilization of liquid polymer compositions. However, studies have focused on the fludge evaporation method, and various improved methods have been proposed. However, Japanese Patent Publications No. 38-120, Japanese Patent Publication No. 44-20097, and Japanese Patent Publication No. 45-3 show that the water is allowed to flow down in a strand shape into an evaporation tank under vacuum.
1678, etc., or JP-A-47 using a rotating body to assist in transferring the polymer composition after devolatilization.
Although the methods described in Japanese Patent No. 27872 partially improve the problems of heating, transfer, surface renewal, and prevention of stagnation, none of them can be said to provide a fundamental solution. In these improved methods, the polymer composition under pressure and temperature is directly fed into the blowing shed of the screier extruder maintained under vacuum or atmospheric pressure.
Publication No. 52-17555, Hour 1 @ 51-29914
Although the method described in the publication generally solves the above problems, there is a surface renewal rate in the evaporation space, and devolatilization in the vent section is essential to obtain a sufficiently low residual volatile component content. At first glance, I am not completely satisfied.

In the present invention, a polymer composition containing a large amount of volatile components is heated to a predetermined pressure and temperature, and then devolatilized by directly blowing it into the gap between the inner surface of the stator and the outer surface of the rotor through the pores. This is a method and apparatus for removing the volatile components and the polymer composition after devolatilization from opposite directions with respect to the pore position, and thereby the above-mentioned heating, transfer,
The present invention is characterized by providing a method that solves the problems of surface renewal or stoppage prevention all at once, and also enables continuous operation for a long period of time.

That is, the present invention provides a thermoplastic polymer composition 4 containing volatile components such as unreacted monomers, solvents and/or by-products,
In separating volatile components from the composition, sufficient pressure is applied to maintain the composition in a substantially liquid phase state, and all or part of the amount of heat necessary to volatilize the volatile components in the composition is applied to the composition. After applying this to the rotor, it is arranged in the order of the volatile component outlet, the pore, and the outlet for the devolatilized polymer composition from the drive part side to the tip side of the rotor, and the inside is vacuumed at 5 Torr. Penetrating the stator of the devolatilizing extruder under pressure conditions of 2 to 2 atmospheres.
Most of the volatile components are separated by supplying the volatile components through the pores provided in the devolatilizing extruder and blowing directly into the gap formed by the inner surface of the stator and the outer surface of the rotor. The polymer composition is taken out from the outlet and collected, and the rotation of the rotor generates shearing force and discharge force to rapidly transfer and heat the polymer composition toward the tip of the rotor, while completing the separation of the remaining volatile components. This is a devolatilizing extrusion method that consists of taking out this from an outlet provided on the stator at the tip end of the rotor.

The present invention also provides a rotor and a stator that are arranged to form a certain gap, and a pore portion that passes through the stator and is arranged to face the outer surface of the rotor for supplying a polymer composition. a mechanism for adjusting the pore gap to maintain the pressure of the supplied polymer composition; a drive mechanism for rotating the rotor;
a mechanism provided on the rotor for generating a discharge force; a shaft sealing mechanism for maintaining the space within the device under a predetermined pressure;
A volatile component extraction port placed in the direction of the drive unit to take out volatile components, an outlet placed in the direction of the rotor tip to take out the devolatilized polymer composition, and a discharge port placed in the direction of the rotor tip to generate # and discharge pressure. This is a devolatilization extrusion device consisting of a mechanism for adjusting the opening degree of the outlet port.

The present invention will be explained below with reference to the drawings.

FIG. 1 shows a front sectional view of an example of a devolatilizing extruder suitable for carrying out the method of the present invention.

It contains 25 to 99.9% by weight of volatile components such as unreacted monomers, solvents and/or by-products, preferably 40 to 99% by weight, and is equipped with a needle valve 4 for predetermined pressure and temperature control. A rotor 8 having a zero-rotation surface 7 introduced into a gap 6 in the devolatilizing extruder through a hole 5 is rotated by a rotating shaft 10 supported by a shaft seal 9 . The stator inner surface 3 and the rotor outer surface 7 face each other with a predetermined gap therebetween, and the gap 6 formed therebetween is maintained under a vacuum of 5 Torr or a pressure of 2 atmospheres. The stator 2 and/or the rotor 8 are provided with a heat medium circuit 11 for heating the polymer composition in the gap 6 . The volatile components separated in the gap 6 are led out and collected from a volatile component outlet 12 provided in the direction of the outer circumference of the rotating surface. The polymer composition from which most of the volatile components have been separated is transferred toward the tip of the rotor 8 by the discharge force generated by the rotation of the rotor 8, but during this time it is also transferred from the stator inner surface 3 and/or the rotor outer surface. Devolatilization continues to be accelerated by thermal conduction heating, shear heat generation, and surface renewal due to shear. After the devolatilization, the polymer composition is densified by the action of a rotor 8, preferably a screw, and then passed through an extrusion die 1 near the tip of the rotor.
The polymer composition is taken out from the outlet port 14 provided at 3. Under steady operating conditions, the gap 6 in the devolatilizing extruder is kept substantially empty except for the vicinity of the extrusion die 13 by the discharge force of the rotor 8, so devolatilization is completed in a short period of several seconds. Therefore, the residence time of the polymer composition in the machine from when it is supplied from the pores 5 to when it is discharged from the outlet 14 can be extremely shortened.

As is clear from its operating principle, the arrangement of the devolatilizing extruder used in the method of the present invention may be such that the axis of rotation is vertical, horizontal, or somewhere in between; however, it is usually as shown in Figure 1. The rotation axis is placed in the horizontal direction.

When continuously manufacturing resinous or rubbery thermoplastic composite compositions used for manufacturing molding materials or extruded plates, etc. by bulk polymerization or solution polymerization, heat balance, prevention of by-product acids, and polymerization stability are important. Generally 130-1 due to restrictions such as gender.
Polymerization conditions of 70°C and a liquid viscosity of 10-10 to several thousand poise are considered suitable, but conventional methods, such as Japanese Patent Publication No. 52-17
In the method described in Japanese Patent Publication No. 555 and Japanese Patent Publication No. 51-29914, the polymer composition is heated at a sufficiently high temperature before devolatilization, for example, 210°C in the case of a methyl methacrylate resin composition.
It was essential to provide almost the entire amount of heat necessary for volatile separation by heating to a temperature of 250 to 270° C. or higher. In contrast, in the method of the present invention,
Stator inner surface 3 and/or rotor outer surface 7 of a devolatilizing extruder
The amount of heat supplied by heat transfer from the outside through the wafer and the amount of heat generated by shearing of the polymer composition between the two surfaces both effectively increase the temperature of the polymer composition, so special heating is not necessarily required in the previous stage. The amount of heat required to separate volatile components is provided without requiring the installation of equipment. Therefore, there is an advantage that polymer compositions containing a large amount of volatile components can also be treated suitably. Moreover, an apparatus for heating the polymer composition to raise its temperature may be additionally used. Due to the high viscosity and thermal deterioration properties of the polymer composition, the equipment used at this time has as high an overall heat transfer coefficient as possible (has self-cleaning properties,
A scraper or heat exchanger that can shorten the residence time, such as an extruder type in which a screw with a small flight gap is rotated at high speed, is suitable.

In the method of the present invention, the polymer composition supplied through the polymerization step and/or the heat exchanger is provided with a portion of the heat necessary for volatilizing the volatile components contained therein. It is sufficient if the volatile components are 60~
Even in the case of a polymer composition containing as much as 99.9% by weight, it has the advantage that it can be suitably processed without raising the temperature in a heat exchanger to a high temperature that would cause quality deterioration. The thermoplastic polymer composition to be treated may be produced by the above-mentioned continuous production method, or may be produced batchwise. Process liquids or waste liquids containing thermoplastic polymers obtained from other manufacturing processes such as condensation polymerization, addition polymerization, and ring-opening polymerization may also be used. It should be noted that if the volatile component exceeds 99.9% by weight, it is not suitable because it becomes difficult to effectively develop the ejection force.

The polymer composition leaving the polymerization process and/or heat treatment device is heated to a temperature 50°C or more higher than the boiling point of the volatile components normally contained therein to volatilize the volatile components contained therein, and the amount of heat required for volatilization is Since all or part of the volatile components are given, the temperature is preferably 120 to 330°C, and in the case of methyl methacrylate resin, preferably 150 to 250°C, and the vapor pressure of the volatile components is high. ,
Usually 2 to 100 I/M, preferably 10 to 50 to suppress the generation of bubbles in the polymer composition and maintain the liquid phase state up to the pores installed just before the devolatilizing extruder.
Immediately pressurized to high pressure of ♂G. Although the pressure in the polymerization step and the heat exchanger may be the same, a pressure booster may be added to the heat exchanger.

When the temperature of the polymer composition supplied to the devolatilizing extruder is lower than this range, it becomes difficult to sufficiently reduce the content of residual volatile components in the devolatilized polymer composition;
When the temperature is higher than 30°C, the polymer composition itself is thermally altered and deteriorated, which is not preferable. Furthermore, when the pressure applied to the polymer composition is lower than 2 KP/nG, bubbles are generated due to boiling of the volatile components, making it difficult to maintain the liquid phase state; This method not only does not have the following characteristics, but also increases the burden on manufacturing and operating the device, both of which are undesirable.

The polymer composition under high temperature and high pressure is passed from the outside of the stator side through the pores 5 into the gap 6 provided in a vacuum of 5 Torr to 2 atmospheres, preferably a vacuum of 5 Q Torr to atmospheric pressure. Directly emitted. At this time, if the pressure inside the devolatilizing extruder is higher than 2 atm, the separation of volatile components will be insufficient, while if it is lower than 5 Torr, the residual volatile content in the polymer composition can be reduced, but the pores The apparent specific gravity after ejection from the rotor 5 becomes low and bulky, resulting in a reduction in processing capacity, the condensation device for volatile components becomes excessively large, and leakage prevention from the shaft seal 9 of the rotor 8 becomes complicated, etc. Both are undesirable.

The functions of the pores 5 include creating the necessary pressure drop as a boundary between the high pressure section and the low pressure section, and increasing the flow rate of the discharged polymer composition to aid in the separation of volatile components.

As long as the polymer composition maintains a liquid phase state, the pressure drop essentially depends on its viscosity, but in reality, the pressure loss is maintained as a result of foaming in the middle of the pores 5. . However, if the pressure loss is too small, or if the pressure loss in the E flow in the pores 5 is relatively large, volatile components may blow through, making the flow unstable, or inside the heat exchanger etc. Localized increase due to foaming is undesirable as it may cause flow stagnation and cause alteration or deterioration. 5 pressure losses are adjusted. Also, since the above-mentioned blow-through and stagnation are undesirable in the connecting part from the pore part 5 to the inside of the devolatilizing extruder, the pore part 5 is installed as close as possible immediately before the devolatilizing space inside the extruder. It is preferably placed through the stator 2 and arranged so that the polymer composition is blown directly into the gap 6.

The number of pores 5 in the method of the present invention is usually one, but a plurality of pores may be provided.

The process by which volatile components are separated from the polymer composition within the devolatilizing extruder of the method of the present invention conceptually consists of two steps. First, volatile components corresponding to the amount of heat added to the polymer composition in the preceding polymerization step and/or heat exchanger instantaneously cause rapid volatilization and foaming near the exit of the pore section 5 and are separated. The second is heat transfer from the outside or shear heat generation of the polymer composition while the polymer composition is transferred toward the tip of the rotor 8 by the discharge force generated by the rotation of the rotor 8. Therefore, the additional heat supplied and the effect of renewing the volatilization interface due to shear combine to substantially complete most of the devolatilization. However, these two processes actually proceed concurrently, and a high level of devolatilization can be easily achieved in substantially one step.

According to the method of the present invention, rapid volatilization and foaming occur instantaneously near the exit of the pore portion 5, but before the explosive force causes very large foaming, the opposing stator inner surface 3 and/or Since it is sprayed onto the outer surface of the rotor and a shearing force is applied between both surfaces to immediately form open bubbles, the volatile components are smoothly recovered from the direction of the drive section of the rotor 8, and the increase in volume due to foaming is minimized. , and while the separated polymer composition is being transferred toward the tip of the rotor 8 by the discharge force generated by the rotation of the rotor 8, it is constantly kneaded by a large shearing force acting in the direction of rotation, thereby causing evaporation. Since the surface is renewed, the time for having a bulky and large evaporation area can be extremely shortened, and during this time, the heat transfer from the stator inner surface 3t and/or the rotor outer surface 7 due to the high overall heat transfer coefficient or the shear force The heating of the polymer composition due to the accompanying heat generation is carried out uniformly in a short period of time, so the separation of volatile components is accelerated and continued, and the content of residual volatile components in the polymer composition is extremely efficiently reduced. can be done. In addition, the polymer composition from which most of the volatile components have been separated is immediately densified by the discharge force and taken out from the outlet 14 provided in the extrusion die 13 near the tip of the stator. The residence time can be made extremely short, and it also has the advantage that deterioration and deterioration are unlikely to occur even in the treatment of polymer compositions containing thermally unstable components.

In the present invention, the rotor outer surface 7 and the stator inner surface 3 cooperate with each other by the rotation of the rotor 8 to generate a shearing force and a discharge force, which moves the polymer composition toward the tip of the rotor 8 and unreacts the polymer composition. The Krieux groove can be provided in any shape as long as it has the function of taking out volatile components such as monomers, solvents, and/or by-products in the opposite direction. FIG. 2 shows a front sectional view of one example, and parts with the same numbers have the same names as in FIG. 1. The screw grooves have appropriate groove depths, for example, a deep groove section 8, a groove depth changing section 8', and an initial and shallow groove section 8'', as in a conventional vent extruder.

In addition, although a smooth surface is generally used for the stator inner surface 3,
For the purpose of increasing the heat transfer area or increasing the shearing force, a special uneven shape such as a helical groove may be provided.

The pore portion 5 provided on the stator side is arranged at an intermediate position between the tip of the rotor 8 and the volatile component outlet 12 on the drive unit side, and preferably the pore portion 5 and the volatile component outlet 12 are located on the rotor side. When the 80-axis diameter is D, they are arranged at a distance of 2D or more, preferably 3D or more in the axial direction. If the pores 5 are too close to the tip of the rotor 8, the volatile components will reach the extrusion die 13 and be discharged from the outlet 14 without being sufficiently separated. If the polymer composition is too close to the volatile component outlet 12 of the polymer composition, the polymer composition reaches the volatile component outlet 12 before sufficient shearing force and ejection force are developed, and tends to foam, and the non-volatile components are mixed with the recovered volatile components and discharged. As a result, continuous operation becomes impossible, which is undesirable.

In order to supply the polymer composition with the necessary and sufficient amount of heat for volatilization by heat transfer from the rotor outer surface 7 and/or the stator inner surface 3), the rotor 8 and/or the stator 2 are The heated heat medium and steam are also circulated. Temperature of heat medium: Normally 180-350℃, preferably 200-3
You can choose between 30℃. When it is lower than this range, the separation of volatile components is insufficient, while when it is higher than this range, 1
The number ζ and the number ζ cause deterioration and deterioration of the polymer composition, so any deviation is undesirable. In addition, the temperature of the polymer composition and the devolatilization extrusion are adjusted so that the temperature when the air is blown into the gap 6 through the pore 5 is 20°C or more higher than the glass transition temperature of the polymer composition after devolatilization. The degree of vacuum inside the aircraft is selected. At this time, since the discharge force can be quickly developed, the device efficiency of the devolatilizing extruder can be particularly increased, and therefore, there is an advantage that the device can be made smaller.

In the method of the present invention, the residual volatile component content in the polymer composition after devolatilization is usually 0.3 to 10% by weight, and the apparent specific gravity is 0.
．． It is between 5 and 1.3. Under preferred operating conditions, one-step devolatilization results in a residual volatile content of 0.3 to 1.
．． It was an unexpected discovery that a polymer composition with an apparent specific gravity of 0% by weight and an apparent specific gravity of 1.05 to 1.25 and substantially free of air bubbles could be obtained.

By the method of the present invention, the desired resinous or rubbery thermoplastic iris polymer can be easily and efficiently separated from a liquid polymer composition with a relatively high polymer content obtained by a bulk type method or a solution polymerization method. A method is provided. Furthermore, when polymerized to a high polymer content, a crosslinked structure is formed and the liquid polymer composition has a low polymer content of about 10% by weight, such as diene polymers or copolymers, which tend to gel. However, this method provides a suitable separation method even for compositions that are difficult to devolatilize using conventional devolatilization methods.
Suitable separation methods are also provided for polymer compositions such as polyhydroxy polyethers.

Furthermore, a method is provided for easily recovering expensive monomers or solvents from waste liquids containing thermoplastic polymers with high purity and high yield. That is, the method of the present invention has the feature that it can be applied over a wide range of polymer content ranging from 0.1 to 75% by weight, preferably from 4 to 60% by weight.

If the purpose is to obtain a polymer composition, the polymer composition obtained here can be cooled, cut, and packaged using a conventional method to be used as a molding material, paint resin, film resin, etc. can be provided. In addition, when the purpose is to recover monomers or solvents, the recovered liquid obtained here can be reused as is or purified by conventional methods before use.

The content of residual volatile components decreases as the temperature increases, the degree of vacuum increases, and the shear force increases. On the other hand, the lower the temperature and the weaker the shearing force, the smaller the apparent specific gravity and the higher the bulk. After careful consideration of the best option for reducing the residual volatile content and increasing the apparent specific gravity, we determined that the temperature of the polymer composition and the degree of vacuum in the devolatilizing extruder were within the ranges mentioned above. Select,
and the gap between the rotor outer surface 7 and the stator inner surface 3 and the rotor 8
It was recognized that it is effective to select the optimum conditions for shear force by adjusting the rotation speed of the shear force. This surface gap is usually 0.0
2~lQm*, preferably 0.05~2111+111
If it is narrower than this range, the power will be excessive and it will be difficult to increase the volume due to foaming, making it difficult to discharge volatile components smoothly. On the other hand, if it is wider than this range, the shear force will be weak. Neither of these are desirable. The rotation speed is usually 50 to 1,000 rpm, preferably 100 to s.
oo rpm, and if it is smaller than this range, the necessary shearing force and/or ejection force cannot be obtained, and if it is larger, structural problems such as axial vibration of the rotor 8 will occur, both of which are undesirable.

The devolatilizing extruder used in the process of the present invention can usually be used in stages to sufficiently reduce the content of residual volatile components in the polymer composition to a desired level, but if necessary, two or more units can be used in series. Alternatively, a conventionally known vent extruder may be used in series as the second stage devolatilization section. FIG. 3 shows a front sectional view of one example. In the figure, 1 to 1
Each number 4 has the same name as the first edict and figure 2, 15 is a ring slit, 16 is a ventro, 17.17', 17'
indicate a part of the deep groove screw, a part of the groove depth change part $, and a part of the shallow groove screw, respectively.

Thermoplastic polymers according to the method number ζ# of the present invention include methyl methacrylate, alkyl methacrylate (wherein the alkyl group has 2 to 8 carbon atoms), alkyl acrylate (where the alkyl group has 1 to 8 carbon atoms), (having an alkyl group of Homopolymers of unsaturated monomers such as or copolymers containing 60 weight or more of one or more of these, ethylene/vinyl acetate copolymers, ethylene/alkyl acrylate copolymers (However, the alkyl group has 1 to 8 carbon atoms), E
Derived from PDM and bisphenol A, the following formula (I)
It means one or more selected from condensation, addition, or ring-opening polymers such as substantially linear polyhydroxypolyether compounds having repeating structural units represented by the following.

(In the formula, n is 80 to 300) In addition, in the method of the present invention, the solvent is not particularly limited as long as it can be mixed substantially uniformly with the thermoplastic polymer, but when the thermoplastic polymer is polystyrene, Examples of solvents used in the polymerization process include ethylbenzene, n-hexane in the case of polybutadiene and EPDM, and methyl ethyl ketone in the case of polyhydroxypolyether.

Furthermore, the thermoplastic polymer composition referred to in the method of the present invention includes:
The above thermoplastic polymer, its unreacted monomer, solvent and/or
The composition also includes additives such as heat stabilizers, ultraviolet absorbers, colorants, plasticizers, mold release agents, lubricants, and surface active agents. fiber,
It includes those containing various fillers such as inorganic salts and metal oxides in an amount equal to or less than the weight of the thermoplastic polymer. These thermoplastic polymer compositions are not limited to reaction products obtained by bulk polymerization or solution polymerization, but may also be waste liquids containing thermoplastic polymers discharged from various processes.

Hereinafter, the method of the present invention will be explained by examples, but the present invention is not limited by these examples.

Example! The apparatus shown in Figure 1 was used. Screw diameter is D=30
myn, the deep groove portion 8 has a length of 4D and a groove depth of 6 mm.

The groove depth changing part 8' has a length of 2D, and the shallow groove part 8' has a length of 6D and a groove depth of 1.5 mm. Both are single screws with a pitch of D. During flight, the groove depth is 5 mm, n5vt, and the flight gap is 0.5 mm. 2-m
Met. Further, the pore portion 5 was arranged opposite to the groove depth changing portion of the screw, and had a distance of 4D from the volatile component outlet 12 in the axial direction of the screw. The polymer composition outlet nozzle 14 had an inner diameter of 3 mm.

Methyl methacrylate-ethyl acrylate copolymer 4 obtained by bulk polymerization of a monomer mixture consisting of 92 weight sb of methyl methacrylate and 8 weight of ethyl acrylate
17% by weight, 49% by weight of methyl methacrylate monomer, and 6% by weight of ethyl acrylate monomer.
The polymer composition under temperature and pressure conditions of 0° C. and 10 atm is pressure-regulated by a needle valve provided in the devolatilizing extruder barrel 2, and passed through the fine hole 5 to the outer surface of the screw 7 and the barrel rotating at 480 rpm. The air was blown directly into the gap 6 formed between the inner surface 3 and the inner surface 3. At this time, the inside of the devolatilizing extruder is 2
The temperature was maintained at 60 Torr, and a 250° C. heat medium was circulated in the heat medium circulation path 11 provided in the barrel 2.

The polymer composition from which the volatile components have been separated is passed through the polymer composition outlet 14 provided in the extrusion die 13 near the tip of the barrel.
It was extracted at a rate of 1 KP/hr. The final polymer composition contains almost no air bubbles and has a residual volatile content of 0.
It was 3% by weight. In addition, the separated volatile components are removed from the exhaust port 12.
It was taken out, condensed and recovered, and the recovery rate was higher than the theoretical value of 98%. As a result of continuous operation for 12 hours under these conditions, no adhesion of the polymer composition to the exhaust port 12 was observed.

Examples 2 to 7 Using the apparatus of Example 1, liquid polymer compositions having the compositions shown in Table 1 were subjected to devolatilization extrusion. The screw is ao in both cases.
o rpm. These liquid polymer compositions were heated and pressurized to the temperature and pressure shown in Table 1, and supplied at a flow rate of 51/hr through a needle valve 4 to a surface gap open to atmospheric pressure. A heating medium having a temperature shown in Table J11 is circulated in the heating medium circulation path 11, and the residual volatile component content in the polymer composition taken out from the outlet 14 is as shown in Table 1. All of them were extremely small and contained almost no air bubbles, and no increase in coloring, gelation, or hydrolysis was observed.

[Brief explanation of the drawing]

Fig. 1 is a front sectional view of an example of a devolatilization extrusion device suitable for carrying out the method of the present invention, and Fig. 2 is a front sectional view of an example in which the rotor is provided with screw grooves to increase the discharge force. The figures each show a front sectional view of an example in which a vent P is provided at the rear stage to reinforce the devolatilization ability. In FIGS. 1 to 8, l is the polymer composition inlet, 2 is the stator (barrel), 8 is the stator inner surface (barrel inner surface), 4 is the needle valve, 5 is the pore portion, 6 is the gap portion, and 7 is the rotor outer surface (
outside the screw, 8 is a rotor (screw), 9 is a shaft seal, 10 is a rotating shaft, 11 is a heat medium circulation path, 12 is a volatile component outlet, 18 is an extrusion die, and 14 is a heavy body composition. (Figures in parentheses correspond to Figures 2 and 8). Further, in FIGS. 2 and 8, r, 8.17 indicates a part of the shallow groove screw, 8' and 17' indicate groove depth changing parts, and 8' and 17' indicate a part of the deep groove screw, respectively. Written amendment to the procedure for drunkenness (instruction) - Indication of the case 1982 Patent review No. 30917 - Name of the invention Order for devolatilization extrusion device and its device, person making the amendment Relationship with the case Patent applicant address Daigan City Higashi 5-15 Kitahama, Ward Name (
209) Sumitomo Chemical Co., Ltd. Kinsha Representative Hijikata
Masato Takeyo

Claims (1)

[Claims] (11) In separating volatile components from an ink thermoplastic heavy metal composition containing volatile components of unreacted monomers, solvents and/or by-products, the composition is After applying sufficient pressure to maintain the composition in a substantially liquid state and all or part of the amount of heat necessary to volatilize the volatile components in the composition, the composition is transferred to the shaft of a rotor. The volatile component outlet, the pore section, and the outlet for the devolatilized polymer composition are arranged in this order from the drive part side to the tip side, and the inside is under a vacuum of 5'rorr or a pressure of 2 atmospheres. A cylindrical tube that penetrates the stator of a certain devolatilizing extruder and is supplied far from the pores, and is composed of the stator white area and the rotor outer area of the devolatilizing extruder. Volatizes by blowing directly into the gap. Most of the components are separated and taken out from the volatile component outlet and collected, and the rotation of the rotor generates shear force and discharge force to transfer the polymer composition to the rotor. A devolatilizing extrusion method characterized by separating the volatile components of the residual metal from the tip direction and heating it, and taking it out from an outlet provided in the rotor tip direction. (2) Devolatilizing extrusion The method according to claim 1, wherein the pores of the rotor and the volatile component outlet are arranged with a distance of 2D or more in the axial direction, where D is the shaft diameter of the rotor. (3) Claim <i> wherein the rotor of the devolatilizing extruder is a screw, and the stator is a barrel cooperating therewith.
The method described in section. (4) Thermoplastic polymers include alkyl methacrylate (however, the alkyl group has 1 to 8 carbon atoms), alkyl acrylate (however, the alkyl group has 1 to 8 carbon atoms), styrene, P- Chlorstyrene, P
-methylstyrene, α-methylstyrene, vinyl acetate,
Acrylonitrile, methacrylonitrile, butadiene,
Homopolymers of isoprene and imbutylene or copolymers containing 60 weight or more of one or more of these, ethylene/vinyl acetate copolymers, ethylene/alkyl acrylate copolymers (however, the alkyl group is ~
8 carbon atoms), EPDM, and a substantially linear polyhydroxy polyether compound derived from bisphenols and having a repeating structural unit represented by the following formula (I) or the method according to claim (1), which is two or more types. (In the formula, n is 80 to 300) (5) The volatile component content in the supplied polymer composition is 2
The method according to claim 1, wherein the weight is 5 to 99.9% by weight. (6) A rotor and a stator arranged to form a certain gap, a pore portion for supplying a polymer composition disposed through the stator and facing the outer surface of the rotor, and a supply. A mechanism for adjusting the gap between the pores to maintain the pressure of the polymer composition, a drive mechanism for rotating the rotor, and a mechanism and device provided on the rotor for generating discharge force. A shaft sealing mechanism to maintain the inner space at a predetermined pressure, a volatile component extraction port arranged in the direction of the drive unit to take out volatile components, and a rotor tip part to take out the devolatilized polymer composition. 1. A devolatilizing extrusion device comprising: a discharge port disposed on a stator in the direction of the direction of the discharge; and a mechanism for adjusting the degree of opening of the discharge port for generating discharge pressure. (7) The device according to claim (6), wherein the rotor is a screw and the stator is a barrel cooperating therewith.