JPH07138329A - Production of high-impact styrenic resin - Google Patents

Abstract

PURPOSE:To obtain a glossy high-impact styrenic resin by controlling the diameters of rubber particles. CONSTITUTION:This high-impact styrene resin is produced by the continuous polymn. process wherein a soln. contg. a styrenic monomer and a rubbery polymer is fed into a series of reactors of a complete mixing type, 2, 4, and 6, to elevate the conversion. In the first reactor 2, the soln. is polymerized under stirring at a Reynolds number of 100-2,500 to control the diameters of the resulting rubber particles. Pref. the first reactor 2 has a stirrer blade of a double helical ribbon type or of a screw type.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing an impact-resistant styrene resin whose rubber particle size can be easily controlled.

[0002]

2. Description of the Related Art In impact-resistant styrenic resins, the rubber particle size has a great influence on the gloss and impact strength of molded articles. Therefore, in the presence of a rubber-like polymer, in the case of producing a high-impact styrene-based resin by grafting a styrene-based single weight to a rubber-like polymer, the technique is how to make the rubber-like polymer uniform and finely dispersed Importantly.

Known factors for controlling the particle size of the rubber-like polymer are the shear rate, the graft ratio, the chemical structure and microstructure of the rubber-like polymer, and the viscosity of the rubber-like polymer. For example, in Japanese Patent Laid-Open No. 4-117447,
A method of changing the shear rate according to the number of rotations of stirring, and Japanese Patent Laid-Open Publication No.
Japanese Patent Laid-Open No. 0-233117 proposes a method in which the clearance between the blade and the reactor is limited to cause the reaction.
Further, JP-A-3-28210 and JP-A-3-712.
JP-A No. 60-233117 and JP-A No. 60-233117 propose to install a particle disperser in a line after rubber phase inversion in order to disperse rubber particles by rotating a stirring blade at high speed and high shear. .

Regarding the continuous bulk polymerization method of impact-resistant styrene type resin, Japanese Patent Laid-Open No. 5-1122 discloses a raw material supply line and a plurality of mixing elements subsequent to the raw material supply line and having no movable parts. An initial polymerization line consisting of an annular reactor fixed inside, a main polymerization line subsequent to this initial polymerization line consisting of an annular reactor inside which a plurality of mixing elements without moving parts are fixed, and said initial polymerization line In a polymerization line constituted by a reflux line branched between a line and a main polymerization line and returning to the initial polymerization line, a Reynolds number in a reactor installed between the raw material supply line and the initial polymerization line. 2800 ~
A method of prepolymerizing with mixing at 4500 is disclosed. According to this prior art document, the Reynolds number is about 100 to 250 on a scale of a pilot plant, but the Reynolds number is 2800 to 4500 on a commercial scale with one series of annual production of about 20,000 to 60,000 tons. Have been described. Further, it is described that the reflux ratio of the polymerization liquid in the circulation polymerization line and the polymerization conversion rate of the styrene-type monomer are important factors for the particles of the rubbery polymer, but the rubber-like material can be obtained depending on the stirring Reynolds number. It is not described that the particle size of the polymer can be controlled.

Regarding the graft ratio, it has been known that when an initiator is added in advance to a solution containing a styrene-based monopolymer and a rubber-like polymer for polymerization, the graft ratio is increased and the particle size is reduced as compared with the thermal polymerization method. Has been.

Furthermore, the chemical structure of the rubber-like polymer (such as the polyene or styrene-butadiene rubber content of the diene or styrene), the microstructure (such as the cis content) or the viscosity of the rubber-like polymer in the styrene solution also affects the rubber particle size. Are known, and many proposals have been made regarding the control of the rubber particle size from these viewpoints.

On the other hand, as a process for producing an impact resistant styrene resin, an economically advantageous continuous bulk polymerization method has become the mainstream process at present. In this continuous bulk polymerization method, from the viewpoint of quality design, productivity, etc., many processes mainly composed of a complete mixing type reactor, a plug flow type reactor and the like have been proposed. Of these, a complete mixing type reactor is often adopted as a reactor for inversion as rubber particles, which allows uniform stirring in a region where the conversion rate to a polymer is low.

However, in the above continuous polymerization method, particularly in the continuous bulk polymerization method, there is no suggestion about the process control related to the control of the rubber particle diameter in the reactor, and the particle diameter of the rubber particles is arbitrarily controlled. Can not. Particularly, in a complete mixing type reactor, complete mixing is performed when the feed rate is relatively slower than the mixing rate. Therefore, in the process in which the feed rate of the mixture is high and the rubber component is phase-inverted, it is difficult to arbitrarily control the rubber particle size in the complete mixing type reactor.

[0009]

SUMMARY OF THE INVENTION It is, therefore, an object of the present invention to provide a method for producing an impact-resistant styrenic resin capable of controlling the particle size of a rubber-like polymer.

Another object of the present invention is to provide a rubber-like polymer even in a complete mixing type reactor in which a mixed solution containing a styrene monomer and a rubber-like polymer is continuously supplied and uniformly mixed. An object of the present invention is to provide a method for producing an impact-resistant styrene-based resin capable of controlling the particle size of

Still another object of the present invention is to provide a method useful for obtaining a styrenic resin having a controlled rubber particle size and high gloss and impact resistance.

[0012]

Means for Solving the Problems As a result of earnest studies to achieve the above-mentioned object, the present inventor has found that in the process of phase inversion of a rubber-like polymer in a perfect mixing type reactor, the stirring Reynolds number is equal to the rubber particle diameter It was found that the rubber particle size can be accurately controlled by making a great contribution to it and adjusting the Reynolds number to complete the present invention.

That is, in the method of the present invention, a mixed solution containing a styrene-based monomer and a rubber-like polymer is polymerized in the first reactor, and polymerization conversion is performed in a reactor subsequent to the first reactor. A method for producing an impact-resistant styrenic resin by increasing the rate, and polymerizing while mixing the mixed solution at a Reynolds number of 100 to 2500 in the first reactor to produce an impact-resistant styrene resin. .

Hereinafter, the present invention will be described in more detail with reference to the accompanying drawings as needed.

FIG. 1 is a flow chart showing an example of a continuous bulk polymerization process. In this example, a mixed solution containing a styrene-based monomer and a rubber-like polymer is continuously supplied to a complete mixing type reactor 2 through a supply line 1 to polymerize the mixture, and the rubber-like polymer is converted into rubber particles. Have been phase-shifted to. Further, the polymerization liquid from the first reactor 2 is sequentially supplied to the subsequent reactors 4 and 6 connected in series to the first reactor 2 to increase the polymerization conversion rate. That is, in this example, the polymerization liquid from the first reactor 2 is supplied to the completely mixed second reactor 4 through the connection line 3 to polymerize, and the polymerization liquid from the second reactor 4 is also supplied. Through the connection line 5,
It is supplied to the complete mixing type third reactor 6 and polymerized to produce an impact resistant styrene resin.

FIG. 2 is a flow chart showing another example of the continuous bulk polymerization process. The same elements as those in FIG. 1 will be described with the same reference numerals.

In this example, a mixed liquid containing a styrene monomer and a rubber-like polymer is continuously fed through a feed line 1 to a completely mixed type first reactor 2 for polymerization, The rubber-like polymer is phase-inverted, and the polymerization liquid from the first reactor 2 is sequentially supplied to the subsequent static type reactors 14, 15, 17 connected in series to the first reactor 2. However, the polymerization conversion rate is increased. Further, the static reactor 15 and the static reactor 17 are connected by a connection line 16.

Of the above processes, in the first reactor 2 for producing rubber particles by inversion of the rubber-like polymer, the Reynolds number Re is not only the diameter of the rubber particles but also the obtained styrene. It has a great influence on the gloss and impact resistance of molded products of resin series.

A feature of the present invention is that in the first reactor,
The point is that polymerization is carried out with stirring at a specific Reynolds number Re. That is, in a molded article of impact-resistant styrene resin, usually, a contradictory relationship between gloss and impact resistance is recognized, and as the gloss increases, the impact resistance decreases. Therefore, it is expected that when the Reynolds number Re is increased, the diameter of the phase-inverted rubber particles is reduced, the gloss of the impact-resistant styrene resin molded article is increased, and the impact resistance is reduced.

However, the Reynolds number Re100 to 2
Polymerization with stirring at 500, preferably 100 to 2300, more preferably about 300 to 2000 (for example, about 500 to 2000) enhances gloss and impact resistance of the molded product even if the mixed liquid is supplied at a high rate. be able to. That is, even if the rubber particle size is small and the gloss of the molded product is large, the impact resistance of the molded product can be enhanced, and even if the rubber particle size is large and the impact resistance is high, the gloss of the molded product can be enhanced. . Reynolds number Re is 100
If it is less than 2, the diameter of the rubber particles becomes too large and the properties of both gloss and impact resistance of the molded product are deteriorated. If it exceeds 2500, the gloss of the molded product is high, but the impact resistance is greatly deteriorated. This can be considered as follows.

In the Navier-Stokes equation of motion, when the Reynolds number Re is small, the ratio of the inertial term to the viscous term is small, and when Re is large, the ratio of the inertial term to the viscous term is large. When the polymerization is carried out with stirring at the Reynolds number Re, it is presumed that the viscosity term and the inertia term contribute to the rubber particle size, and both gloss and impact resistance, which are contradictory properties, can be compatible.

The Reynolds number Re can be calculated by the following equation.

Reynolds number Re = ρ × n × d ² / μ where ρ is the density of the solution (Kg / m ³ ), n is the number of revolutions per second (rps), d is the blade diameter (m), μ represents the viscosity (Kg / m · sec) of the solution.

When the rubbery polymer is phase-inverted by polymerizing while stirring under the above Reynolds number Re, the mixed solution is supplied at a feed rate of 1000 to 10000 kg / hr, preferably about 2500 to 7500 kg / hr. Even if it is manufactured on a commercial scale by a continuous bulk polymerization method with an annual production of about 30,000 to 60,000 tons, the impact-resistant styrene-based resin having the above-mentioned excellent properties can be manufactured. Also,
It is not necessary to provide a reflux line for returning the polymerization liquid to the first reactor between the first reactor and the subsequent reactor.

The Reynolds number Re varies greatly with the blade diameter, as shown in the above equation. for that reason,
At the time of producing the impact-resistant styrene-based resin, the relationship between the rubber particle diameter and the Reynolds number is obtained in advance, and based on this relational expression, the Reynolds number is selected from the range of 100 to 2500 to obtain a desired rubber particle diameter. It is possible to produce an impact resistant styrene resin having the same.

As the first reactor, various reactors can be used as long as the polymerization can be performed while stirring at the Reynolds number Re, but a complete mixing type reactor is preferable. The complete mixing type reactor is only required to be able to stir the mixed liquid containing the styrene-based monomer and the rubbery polymer while maintaining a substantially uniform mixed state, and examples of the stirring blades include anchor blades and double helical blades. , Screw type blades can be used. In order to disperse the rubbery polymer efficiently, the first reactor is preferably equipped with a double helical blade (for example, double helical ribbon stirring blade) or a screw stirring blade.

The subsequent reactor connected to the first reactor may be connected in parallel to the first reactor, but in order to facilitate the construction of production equipment and control of the reaction, it is connected in series. Often connected to.

In the process of the invention, it is preferred that at least the first reactor is a fully mixed reactor,
The type of subsequent reactor is not particularly limited. The reactor following the first reactor is often composed of the complete mixing type reactor or the plug flow type reactor. The plug flow type reactor can be selected from a static mixer type in which a plurality of static mixing elements are fixed and built in without having a movable part, a tower type reactor with a stirrer capable of gentle stirring, and the like.

The number of the subsequent reactors is not particularly limited as long as the polymerization conversion rate can be increased sequentially, and is appropriately selected from the range of usually about 1 to 10 units depending on the type of the reactor. it can. For example, the number of complete mixing type reactors is about 1 to 5, and when the plug flow type reactor is a static mixer type reactor, it is often about 3 to 7 units. The number of other plug flow type reactors is often about 3 to 5.

The styrenic monomer supplied to the first reactor includes, for example, styrene, alkyl-substituted styrene (eg, o-methylstyrene, p-methylstyrene,
m-methylstyrene, 2,4-dimethylstyrene, p-
Ethylstyrene, pt-butylstyrene, etc.), α-
Alkyl-substituted styrene (for example, α-methylstyrene,
α-methyl-p-methylstyrene, etc.), halogenated styrene (eg, o-chlorostyrene, p-chlorostyrene, etc.) and the like. Preferred styrenic monomers include, for example, styrene, p-methylstyrene, α-methylstyrene, especially styrene. These styrene-based monomers may be used alone or in combination of two or more.

The styrene-based monomer may be, for example, (meth) acrylic acid ester such as methyl methacrylate, ethyl acrylate, butyl acrylate, (meth) acrylic acid, maleic anhydride, acrylonitrile, etc., if necessary. The copolymerizable monomer of may be added.

Examples of the rubber-like polymer include polybutadiene rubber, butadiene-isoprene rubber, butadiene-acrylonitrile copolymer, ethylene-propylene rubber,
Non-styrene rubbery polymer containing no styrene unit such as isoprene rubber, acrylic rubber, ethylene-vinyl acetate copolymer; styrene containing styrene unit such as styrene-butadiene copolymer, styrene-butadiene block copolymer Includes rubbery polymers. These rubber-like polymers may be used either individually or in combination of two or more.

The rubber-like polymer can be selected according to the desired characteristics of the styrene resin, and for example, a polymer containing a butadiene unit (for example, polybutadiene) is often used.

The rubbery polymer containing a butadiene unit may be a polymer containing a high cis-1,4 structure content, and may be a polymer containing a low cis-1,4 structure content. It may be a polymer containing units. The molecular weight of the rubber-like polymer can be selected according to the characteristics of the impact-resistant styrene-based resin. For example, it is often about 1 × 10 ^{4 to} 100 × 10 ^{4 in} terms of polystyrene. The viscosity of the 5 wt% styrene solution at 0 ° C. is often about 15 to 2000 cps, for example.

The content of the rubber-like polymer in the mixed liquid charged in the reactor can be selected within a wide range according to the characteristics of the impact-resistant styrene resin, and is, for example, 1 to 25% by weight, preferably 2 to 20% by weight. %, More preferably 3 to 15% by weight
It is a degree.

When the mixed solution containing the non-styrene rubber-like polymer is polymerized, the phase-inverted rubber particle size is likely to be larger than that of the rubber-like polymer containing the styrene unit. In particular,
As the content of the non-styrene rubber-like polymer increases, the rubber particle size usually increases, and the gloss of the molded product tends to decrease. However, when the polymerization is carried out while stirring at the Reynolds number Re, the rubber particle diameter can be controlled and a molded article having high gloss and impact resistance can be obtained even if the content of the rubber-like polymer is large. In order to enhance the gloss and impact resistance of the molded product, a rubber-like polymer in the mixed solution,
In particular, the content of the non-styrene rubbery polymer is preferably about 5 to 15% by weight.

The mixed solution may be a suspension,
In many cases, the solution containing the styrene monomer and the rubber-like polymer is supplied to the first reactor.

The mixed solution containing the styrene-based monomer is a polymerization initiator such as benzoyl peroxide, lauroyl peroxide, cumene hydroperoxide,
Dicumyl peroxide, methyl ethyl ketone peroxide, azobisisobutyronitrile, etc. are often contained, but they are not always necessary in the case of thermal polymerization.

If necessary, a solvent such as benzene, ethylbenzene, toluene or xylene may be added to each of the mixed liquids,
A solvent inert to the reaction such as mineral oil may be added. When a solvent is added, the viscosity of the mixed solution can be adjusted and the particle size of the rubber-like polymer may be easily controlled. The amount of the solvent added is, for example, 100 styrene-based monomers.
30 parts by weight or less, preferably 1 to 20 parts by weight
It is about part by weight. Further, if necessary, the mixed solution
A molecular weight modifier, antioxidant, lubricant, plasticizer and the like may be added.

In the polymerization process of the mixed liquid in the first reactor, the rubber-like polymer is converted into dispersed particles, that is, phase-shifted into the rubber layer, as the polymerization reaction proceeds. The polymerization conversion rate of the styrene-based monomer in the polymerization step is not particularly limited, but is, for example, about 10 to 50%. Further, impact-resistant styrene resin can be obtained by polymerizing up to a high polymerization conversion rate in the final reactor.

The polymerization is carried out, for example, with a stirring of 50 to 2 in an atmosphere of an inert gas such as nitrogen, helium or argon while stirring.
It can be carried out at about 00 ° C., and in the case of thermal polymerization, it is usually carried out at a temperature of 100 ° C. or higher. The polymerization method is not particularly limited, and may be, for example, a bulk polymerization method or a bulk suspension polymerization method in which the bulk polymerization method and the suspension polymerization method are combined.

In the bulk polymerization, after the completion of the polymerization reaction, the unreacted monomer and, if necessary, the solvent are recovered by a known method, for example, a method such as stripping in which degassing treatment is performed under heating. An impact resistant styrene resin can be obtained. Further, in the case of bulk suspension polymerization, usually, a styrene-based monomer is polymerized by bulk polymerization at a predetermined conversion rate (for example, 10 to 50% by weight), dispersed in an aqueous solution containing a suspension stabilizer, and suspended. Complete the polymerization reaction in the turbid state,
After the polymerization is completed, the suspension stabilizer is removed by washing with water or the like, and dried to obtain an impact-resistant styrene resin. The styrene-based resin may be cut into pellet size by a pelletizer while cooling and solidifying the molten and fluid resin by a conventional method.

These production processes may be carried out in a semi-batch system, but in order to improve the production efficiency, the mixed solution is continuously supplied to the first reactor for polymerization, and the first reactor is then polymerized. It is preferable to continuously supply the polymerization liquid of (1) to the subsequent reactor to successively increase the polymerization conversion rate, and particularly to carry out the polymerization by a continuous bulk polymerization method.

In the rubber-modified styrene resin obtained by the above-mentioned polymerization, the content of the rubber-like polymer substantially corresponds to the content of the rubber-like polymer in the mixed solution, and for example, 1 to 2
It is about 5% by weight, preferably about 2 to 20% by weight, and more preferably about 3 to 15% by weight.

When an apparatus in which the first reactor and the subsequent reactor are connected in series is used, in the impact-resistant styrene resin produced by the above process, the average particle size of the rubbery polymer is For example, it is often 0.1 to 15 μm, preferably 0.5 to 10 μm. In addition,
The average particle diameter of the rubber particles can be measured as a volume average particle diameter by a light scattering method using a mixed liquid of a resin and an organic solvent.

In the method of the present invention, a plurality of peaks (for example, two peaks) are included in the particle size distribution of the rubber dispersed particles.
It is also possible to produce a styrene resin having That is, a plurality of first reactors are provided in parallel, and the type and content of the rubber-like polymer in the mixed liquid supplied to each first reactor are changed as necessary, and each first reactor is Polymerization may be performed by adjusting the Reynolds number Re in 1., and the polymerization liquids from these first reactors may be combined and polymerized in the subsequent reactor. In such a method, in the first reactor,
Since the particle size of the rubber particles can be arbitrarily controlled by the Reynolds number Re, an impact-resistant styrene resin having a rubber particle size corresponding to the Reynolds number Re in each first reactor can be manufactured. The styrene-based resin having such a plurality of rubber particle size peaks is useful for further improving impact resistance and gloss.

The styrene resin having a plurality of peaks with respect to the rubber dispersed particles is (A) an average rubber particle diameter of 0.1 to 5.
μm, preferably about 0.5 to 5 μm small particles,
(B) Average rubber particle diameter 0.5 to 15 μm, preferably 1
It may have a distribution consisting of two peaks dispersed in large particles of about 10 μm.

The impact-resistant styrenic resin may include stabilizers against heat, light and oxygen (for example, antioxidants, ultraviolet absorbers, etc.), flame retardants, plasticizers, lubricants, release agents, if necessary. You may add additives, such as an antistatic agent, a coloring agent, and a filler.

The impact-resistant styrenic resin obtained by the method of the present invention is used in various molded products such as household appliances such as daily necessities, vacuum cleaners, refrigerators, washing machines, fans, radios, televisions, and electronic devices. It can be used for a wide range of applications such as housings and interior / exterior parts for vehicles.

[0050]

According to the method of the present invention, the particle size of the rubber-like polymer can be easily controlled by a simple operation of adjusting the Reynolds number to produce an impact-resistant styrene resin. Even in the case of a complete mixing type reactor, the particle size of the rubber-like polymer can be controlled. Furthermore, by adjusting the Reynolds number in the first reactor, it is possible to obtain a styrene-based resin having a controlled rubber particle diameter and high gloss and impact resistance.

[0051]

The present invention will be described in more detail based on the following examples, but the invention is not intended to be limited to these examples. The rubber particle size, the gloss of the molded product and the impact resistance were measured as follows.

(1) Rubber particle size 0.2 g of a resin sample was added to methyl ethyl ketone / acetone = 1
The mixture was mixed with 10 ml of a mixed solvent of 1/1 (v / v), and the volume average particle size was measured by a light scattering method using a particle size analyzer.

(2) Surface gloss Using an injection molding machine, a test piece was molded at a cylinder temperature of 200 ° C. and a mold temperature of 45 ° C., and measured at an incident angle of 60 ° according to JIS Z8741.

(3) Izod impact strength It was measured according to ASTM D256.

Example 1 Using a device constituted by the reactors shown in FIG. 1 in which a plurality of completely mixed reactors were connected in series, 7% by weight of polybutadiene, 90% by weight of styrene and 3% by weight of ethylbenzene were used.
Was continuously fed to the first reactor of the complete mixing type equipped with a double helical blade at 4000 kg / hr, and the mixture was polymerized at 125 ° C. with stirring, and the polymerization liquid was sequentially fed to the subsequent reactors. Polymerization was carried out by continuously feeding to increase the polymerization conversion rate.

The stirring Reynolds number in the first reactor was 490, the polymerization conversion rate was 30%, and the polymerization conversion rate in the final reactor was 83%.

Example 2 Using the apparatus composed of the reactor shown in FIG. 1, a solution of 9% by weight of polybutadiene, 82% by weight of styrene and 3% by weight of ethylbenzene was mixed with a solution of a complete mixing type equipped with a double helical blade. One reactor was continuously fed at 4000 kg / hr, polymerization was carried out at 135 ° C. with stirring, and the polymerization liquid was continuously fed to the subsequent reactor continuously to increase the polymerization conversion rate.

The stirring Reynolds number in the first reactor was 120, the polymerization conversion rate was 40%, and the polymerization conversion rate in the final reactor was 94%.

Example 3 Using the apparatus composed of the reactor shown in FIG. 1, a solution of 4% by weight of polybutadiene, 94% by weight of styrene and 2% by weight of ethylbenzene was mixed with a solution of a first type of a complete mixing type equipped with a double helical blade. Was continuously fed to the reactor at 4000 kg / hr, polymerization was carried out at 135 ° C. with stirring, and the polymerization solution was continuously fed to the subsequent reactor continuously to increase the polymerization conversion rate.

The stirring Reynolds number of the first reactor is 33.
0, the polymerization conversion rate was 38%, and the polymerization conversion rate in the final reactor was 92%.

Example 4 Using the apparatus composed of the reactor shown in FIG. 1, a solution of 11% by weight of polybutadiene, 85% by weight of styrene and 4% by weight of ethylbenzene was mixed with a solution of the first type of a complete mixing type equipped with a screw blade. It was continuously supplied to the reactor at 4000 kg / hr, polymerization was carried out at 135 ° C. with stirring, and the polymerization liquid was continuously supplied to the subsequent reactor continuously to increase the polymerization conversion rate.

The stirring Reynolds number of the first reactor is 18
0, the polymerization conversion rate was 36%. The polymerization conversion rate in the final reactor was 92%.

Example 5 7% by weight of polybutadiene, 90% by weight of styrene and 3% by weight of ethylbenzene were used by using the apparatus shown in FIG. 2 in which the first reactor of the complete mixing type and three static mixer type reactors were connected in series. 5000 kg of the solution consisting of in a completely mixed first reactor equipped with a double helical ribbon blade.
/ Hr for continuous polymerization, polymerization was carried out at 130 ° C. with stirring, and the polymerization solution was continuously supplied to subsequent reactors continuously to increase the polymerization conversion rate.

The stirring Reynolds number of the first reactor is 70.
0, the polymerization conversion rate was 28%, and the polymerization conversion rate in the final reactor was 86%.

Example 6 Using the apparatus composed of the reactor shown in FIG. 2, a solution of 6% by weight of polybutadiene, 92% by weight of styrene and 2% by weight of ethylbenzene was mixed with a solution of the first type having a double helical ribbon blade. Was continuously fed to the reactor at 5000 kg / hr, polymerization was carried out at 130 ° C. with stirring, and the polymerization solution was continuously fed to subsequent reactors continuously to increase the polymerization conversion rate.

The stirring Reynolds number of the first reactor is 54.
0, the polymerization conversion rate was 32%, and the polymerization conversion rate in the final reactor was 82%.

Example 7 Using the apparatus composed of the reactor shown in FIG. 1, a solution of 7% by weight of polybutadiene, 90% by weight of styrene and 3% by weight of ethylbenzene was mixed with a solution of the first type having a double helical ribbon blade. Was continuously fed to the reactor at 5000 kg / hr, polymerization was carried out at 130 ° C. with stirring, and the polymerization solution was continuously fed to subsequent reactors continuously to increase the polymerization conversion rate.

The stirring Reynolds number of the first reactor is 110.
0, the polymerization conversion rate was 25%, and the polymerization conversion rate in the final reactor was 85%.

Example 8 Using the apparatus constituted by the reactor shown in FIG. 1, a solution of 7% by weight of polybutadiene, 90% by weight of styrene and 3% by weight of ethylbenzene was mixed with a solution of a first type having a double helical ribbon blade. Was continuously fed to the reactor at 5000 kg / hr, polymerization was carried out at 130 ° C. with stirring, and the polymerization solution was successively assaulted in the subsequent reactor to increase the polymerization conversion rate.

The stirring Reynolds number of the first reactor is 200.
0, the polymerization conversion rate was 22%, and the polymerization conversion rate in the final reactor was 83%.

Example 9 Using the apparatus composed of the reactor shown in FIG. 2, a solution consisting of 7% by weight of polybutadiene, 90% by weight of styrene and 3% by weight of ethylbenzene was mixed with the solution of the first reaction type equipped with screw blades. It was continuously fed to the reactor at 4000 kg / hr, polymerization was carried out at 125 ° C. with stirring, and the polymerization liquid was continuously fed to the subsequent reactor successively to increase the polymerization conversion rate.
The stirring Reynolds number of the first reactor was 500, the polymerization conversion rate was 30%, and the polymerization conversion rate in the final reactor was 83%.

Example 10 Using the apparatus constituted by the reactor shown in FIG. 2, a solution consisting of 4% by weight of polybutadiene, 94% by weight of styrene and 2% by weight of ethylbenzene was mixed with the solution of the first reaction type equipped with screw blades. It was continuously fed to the reactor at 4000 kg / hr, polymerization was carried out at 135 ° C. with stirring, and the polymerization liquid was continuously fed to the subsequent reactor successively to increase the polymerization conversion rate.
The stirred Reynolds number of the first reactor was 300, the polymerization conversion rate was 38%, and the polymerization conversion rate in the final reactor was 92%.

COMPARATIVE EXAMPLE 1 Using the apparatus composed of the reactor shown in FIG. 1, a solution consisting of 9% by weight of polybutadiene, 82% by weight of styrene and 3% by weight of ethylbenzene was mixed with a solution of a first complete mixing type equipped with a double helical ribbon blade. Was continuously fed to the reactor at 4000 kg / hr, polymerization was carried out at 135 ° C. with stirring, and the polymerization solution was continuously fed to subsequent reactors continuously to increase the polymerization conversion rate. The stirring Reynolds number of the first reactor was 90, the polymerization conversion rate was 35%, and the polymerization conversion rate in the final reactor was 94%.

COMPARATIVE EXAMPLE 2 Using the apparatus composed of the reactor shown in FIG. 2, a solution containing 7% by weight of polybutadiene, 90% by weight of styrene and 3% by weight of ethylbenzene was mixed with a solution of the first type having a double helical ribbon blade. Was continuously fed to the reactor at 5000 kg / hr, polymerization was carried out at 130 ° C. with stirring, and the polymerization solution was continuously fed to the subsequent reactor continuously to increase the polymerization conversion rate. The stirring Reynolds number of the first reactor is 260
0, the polymerization conversion rate was 20%, and the polymerization conversion rate in the final reactor was 86%.

Comparative Example 3 Using the apparatus constituted by the reactor shown in FIG. 1, a solution containing 9% by weight of polybutadiene, 82% by weight of styrene and 3% by weight of ethylbenzene was mixed with the solution of the first type, which was a complete mixing type equipped with a screw cull blade. It was continuously fed to the reactor at 4000 kg / hr, polymerization was carried out at 135 ° C. with stirring, and the polymerization liquid was continuously fed to the subsequent reactor continuously to increase the polymerization conversion rate. The stirring Reynolds number of the first reactor was 90, the polymerization conversion rate was 35%, and the polymerization conversion rate in the final reactor was 94%.
Met.

Then, the surface gloss and impact strength of the impact resistant styrene resins obtained in Examples and Comparative Examples were measured, and the results shown in Tables 1 and 2 were obtained. In addition, Table 1
The reaction conditions are also shown in Table 2.

Further, the relationship between the Reynolds number and the rubber particle diameter is shown in FIG. 3, the relationship between the rubber particle diameter and the gloss of the molded article is shown in FIG. 4, and the Reynolds number and the gloss and impact resistance of the molded article are shown. The relationship is shown in FIG. In FIG. 5, ◯ indicates an example regarding gloss, Δ indicates a comparative example regarding gloss, ● indicates an example regarding impact strength, and ▲ indicates a comparative example regarding impact strength.

[0078]

[Table 1]

[0079]

[Table 2] As is clear from Table 1, Table 2 and FIG. 3, the phase-inverted rubber particle diameter can be accurately controlled by adjusting the Reynolds number in the first reactor regardless of the Examples and Comparative Examples. As shown in 4, there is an inverse relationship between the rubber particle size and the gloss of the molded product. On the other hand, Table 1,
As is clear from Table 2 and FIG. 5, the resins obtained in Examples have higher gloss and impact resistance than the resins of Comparative Examples.
Particularly, the impact-resistant styrenic resins obtained in Examples 1 and 2 and Examples 4 to 9 in which the content of the rubber-like polymer is large are excellent in both gloss and impact resistance.

[Brief description of drawings]

FIG. 1 is a flow diagram showing an example of a continuous bulk polymerization process.

FIG. 2 is a flow diagram showing another example of a continuous bulk polymerization process.

FIG. 3 is a graph showing the relationship between Reynolds number and rubber particle diameter in Examples and Comparative Examples.

FIG. 4 is a graph showing the relationship between the rubber particle size and the gloss of molded articles in Examples and Comparative Examples.

FIG. 4 is a graph showing the relationship between the Reynolds number and the gloss and impact resistance of molded articles in Examples and Comparative Examples.

[Explanation of symbols]

 2 ... First reactor 4, 6, 14, 15, 17 ... Reactor

Claims (6)

[Claims] 1. A shock-resistant resin composition comprising a styrene-based monomer and a rubber-like polymer, which is polymerized in a first reactor and whose polymerization conversion rate is increased in a reactor subsequent to the first reactor. -Resistant styrene-based resin, which is a method for producing a high-performance styrene-based resin, which comprises polymerizing while mixing the mixed solution at a Reynolds number of 100 to 2500 in the first reactor. 2. The method for producing an impact-resistant styrenic resin according to claim 1, wherein the first reactor is a complete mixing reactor. 3. The method for producing an impact-resistant styrene resin according to claim 1, wherein the first reactor is equipped with a double helical stirring blade or a screw stirring blade. 4. The method for producing an impact-resistant styrenic resin according to claim 1, wherein the polymerization liquid from the first reactor is polymerized in a subsequent reactor connected in series with the first reactor. . 5. The method for producing an impact-resistant styrenic resin according to claim 1, wherein at least the first reactor is a complete mixing type reactor, and the subsequent reactors are complete mixing type or plug flow type reactors. . 6. The method for producing an impact-resistant styrenic resin according to claim 1, wherein the polymerization conversion rate is successively increased by a continuous bulk polymerization method.