JPS635413B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a continuous method for producing a rubber-modified impact-resistant resin, which results in a matte surface of the resulting molded product. More specifically, the rubber component is dissolved in a monomer mixture of an aromatic vinyl monomer, a vinyl cyanide monomer, and optionally a monomer copolymerizable with these monomers. By continuously polymerizing the raw material solution in bulk or solution under specific conditions, the resulting molded product has excellent chemical resistance, heat resistance, impact resistance, and rigidity, and the surface of the resulting molded product is matte. The present invention relates to a method for producing a rubber-modified impact-resistant resin. High impact polystyrene resin (hereinafter referred to as HI)
-PS resin) is a resin with improved impact resistance of polystyrene resin obtained by polymerizing styrene in the presence of a rubber component, and is used in a wide range of applications. This HI-PS resin is also produced by batch polymerization such as the bulk-suspension method, but as a recent trend, it is often produced by continuous bulk polymerization. On the other hand, ABS resin obtained by polymerizing styrene and acrylonitrile in the presence of a rubber component is
It has many uses due to its excellent impact resistance, chemical resistance, heat resistance, rigidity, and good surface gloss. This ABS resin is generally manufactured by the so-called emulsion polymerization method, in which styrene and acrylonitrile monomers are added to latex containing a rubber component and polymerized. In the emulsion polymerization method, the amount of latex that is several times the amount of polymer is used, so the polymerization equipment becomes large and various processes such as emulsification, coagulation, and drying are required, making process control complicated. Since additives such as emulsifiers and coagulants are used, there are problems such as impurities being mixed into the polymer. As a method for improving the emulsion polymerization method,
As in No. 35354 and No. 35355, a method has been proposed in which the rubber component in rubber latex is directly extracted with styrene and acrylonitrile monomers, and then transferred to continuous bulk polymerization to produce ABS resin. However, although this method is simpler than the usual emulsion polymerization method, it still requires a complicated extraction step. ABS resin obtained by such emulsion polymerization method is
The surface of the molded product that is obtained generally has a good gloss and is suitable for ordinary uses, but it is not suitable for applications where a matte surface is desired, such as car interior parts, computer housings, office automation equipment, etc., and it is used for various purposes. It is used after being processed. Conventionally known matting methods include, for example, a method in which the surface of a mold or roll is textured, but this method does not provide a sufficient matting effect. There are also methods such as adding titanium, magnesium, and calcium oxides, and applying matte paint to the surface of the molded product.
These methods are not preferred because they reduce the mechanical strength, particularly the impact strength, of the molded product or require time and effort to process. Continuous bulk or solution polymerization methods have been partially proposed as production methods other than emulsion polymerization for ABS.
For example, Japanese Patent Publication No. 45-20303, Japanese Patent Publication No. 47
There are methods such as No. 9144 and JP-A-55-36201.
The polymerization process and post-treatment process are simple, and there are few waste materials that cause pollution. Usually ABS
In bulk or solution polymerization, the rubber component, which initially exists as a homogeneous solution, undergoes phase separation and takes the form of dispersed particles when the polymerization rate of the monomer exceeds a certain level. This is a phenomenon called phase transition, and the dispersed particles generated by this phase transition become the dispersed particles in the final product almost as is, so the adjustment of this phase transition has a great influence on the physical properties of the final product, especially The size of the dispersed particles of the rubber component affects impact strength, gloss, etc., and occupies an important position in the production of rubber-modified impact-resistant resins. In the continuous bulk or solution polymerization method of HI-PS resin, the method of controlling the size of dispersed particles of the rubber component by this phase transition is already widely known and has been industrialized. but,
In the continuous bulk or solution polymerization method of ABS resin,
It is difficult to control this phase transition itself or the size of dispersed particles of the rubber component through this phase transition, which is one reason why ABS resins are generally not produced by continuous bulk or solution polymerization. The various continuous bulk or solution polymerization methods for ABS that have been proposed to date require special equipment, or emulsion polymerization of ABS.
It mainly discloses a method for producing ABS resin with a glossy surface like that of resin, in which phase transition is manipulated to adjust the size of rubber component particles to an appropriate size, and the method of producing ABS resin with a glossy surface like resin is disclosed. A method for producing ABS resin in which the molded product is matte is not disclosed, except in special cases. As a result of extensive research, the inventors have discovered that HI-
Using common equipment such as those used in continuous bulk or solution polymerization of PS resin, under certain limited conditions, it is possible to simplify the above manufacturing method and eliminate the need for secondary processing. We found a way to accomplish two tasks at once. The purpose of the present invention is to
Provided is a method for producing a rubber-modified impact-resistant resin that maintains the properties of ABS resin such as chemical resistance, heat resistance, impact resistance, and rigidity, while the surface of the resulting molded product is matte. It's about doing. Another object of the present invention is to provide a method for producing rubber-modified impact resistant resins which can produce molded articles with matte surfaces but which do not contain large rubber component particles. Another object of the present invention is to provide a method for producing a rubber-modified impact-resistant resin that can extremely effectively prevent a polymer containing a rubber component from adhering to the inner wall of a reaction tank. . In other words, the continuous method for producing a matte rubber-modified impact resin of the present invention is capable of copolymerizing with an aromatic vinyl monomer and a vinyl cyanide monomer, and optionally with these monomers. A weight loss solution in which a rubber component is dissolved in a monomer mixture with a monomer is continuously supplied to the first reaction tank, and polymerization is carried out as necessary to convert the rubber component phase into dispersed particles under stirring shear force. by continuously taking out an amount of reaction liquid corresponding to the supply amount of the raw material solution from the reaction tank, and further supplying this reaction liquid to the second reaction tank and subsequent reaction tanks to continue the polymerization. In the continuous bulk or solution polymerization method of rubber-modified impact-resistant resin, (A) the vinyl cyanide monomer in the monomer mixture is
(B) the raw rubber component is one whose 5% styrene solution at 30°C exhibits a viscosity of 150 centistokes or less; (C) the concentration of the rubber component in the raw material solution is 3. ~15% by weight
(D) One or two chain transfer agents are added to the first reaction tank.
mercaptans or more to the raw material solution,
100 to 5000 ppm is continuously supplied, (E) the first reaction tank is equipped with a screw-type stirring blade with a draft tube, and an auxiliary stirring blade is built in the bottom of the reaction tank, which is the supply part of the raw material solution, The rotational speed N (rps) of the screw type stirring blade in the reaction tank and the diameter φ (m) of the screw type stirring blade
(F) The polymerization rate of the monomer in the ^first reaction tank is controlled to be 10 to 35% by weight, and (G ) The rubber-modified impact-resistant resin obtained is characterized in that the dispersed particles of the rubber component are adjusted to have a volume average particle diameter of 1.5 to 10 μm. In order to achieve the purpose of the present invention, the above (A), (B),
All of (C), (D), (E), (F) and (G) must be satisfied. Even if any one of (A) to (G) is missing, the effects of the present invention cannot be obtained. Examples of the aromatic vinyl monomer used in the present invention include styrene, α-methylstyrene, styrene in which the benzene ring is halogenated, such as o-, m-
Alternatively, one or more of p-methylstyrene, o, m-, or p-tert-butylstyrene, styrene in which the benzene ring is halogenated, such as o-, m-, or p-chloro, or bromustyrene, etc. can be used. . As the vinyl cyanide monomer, one or more of acrylonitrile, methacrylonitrile, etc. can be used. Also,
Monomers that can be copolymerized with these monomers include acrylic esters such as methyl methacrylate, maleic anhydride, and the like, and these monomers that can be copolymerized may be added as necessary. In the monomer mixture, the amount of vinyl cyanide monomer is from 5 to 50% by weight. Vinyl cyanide monomer is 5
If it is less than 50% by weight, the chemical resistance, rigidity and heat resistance of the resulting resin will be poor, and if it exceeds 50% by weight, the fluidity of the resin obtained will be poor, which is not preferable.
Manipulating phase transitions also becomes extremely difficult. In the method of the present invention, the rubber component may be any commonly used rubber component as long as it can be dissolved in these monomers, such as butadiene rubber, styrene-butadiene copolymer rubber, acrylonitrile-butadiene copolymer rubber, etc. rubber, ethylene-propylene-diene copolymer rubber, etc.
Suitable rubber components are those whose 5% styrene solution has a viscosity of 150 centistokes or less at 30°C. If the above viscosity of the rubber component is
If it exceeds 150 centistokes, giant particles may be generated when the rubber component undergoes a phase transition in the first reaction tank, or in some cases gelation may occur without phase transition, resulting in heavy particles containing the rubber component. This is not preferable because the coalescence may adhere to the inner wall of the reaction tank. These rubber components have a concentration in the raw material solution of 3 to 3.
If the concentration of the rubber component in the raw material solution is less than 3% by weight, the concentration of the rubber component in the resulting resin will be low, and therefore it will not be suitable as an impact-resistant resin. This is not preferable because the impact strength becomes low. Additionally, if the concentration of the rubber component in the raw material solution exceeds 15% by weight, the viscosity of the reaction solution in the first reaction tank will increase, and giant particles may be generated during phase transition of the rubber component, or in some cases, This is not preferable because it does not cause a phase transition and causes gelation, which causes the polymer containing the rubber component to adhere to the inner wall of the reaction tank. In the method of the present invention, it is important to continuously supply one or more mercaptans as a chain transfer agent to the raw material solution at a concentration of 100 to 5000 ppm to the first reaction tank. Examples of mercaptans include n-butyl mercaptan, i-butyl mercaptan, tert-butyl mercaptan, n-hexyl mercaptan, n-octyl mercaptan, 2-ethylhexyl mercaptan, n-dodecyl mercaptan, tert-dodecyl mercaptan, etc., which usually contain carbon atoms. number 4-20
Among these alkyl mercaptans, particularly preferred are n-butyl mercaptan, n-butyl mercaptan,
Examples include tert-butyl mercaptan, n-dodecyl mercaptan, and tert-dodecyl mercaptan. These chain transfer agents may be directly dissolved in the raw material solution in some cases. It is generally known that a chain transfer agent is used in the production of ABS resin to improve the fluidity of the resin, but in the present invention, by using a chain transfer agent from the early stage of polymerization, The size of the dispersed particles of the rubber component can be adjusted as defined in the present invention. The amount of chain transfer agent used varies depending on the type of mercaptan used and reaction conditions, but if it is less than 100 ppm,
It is not useful for controlling the particle size, and for reasons that are not clear, the impact strength of the resin obtained is undesirable. On the other hand, if it exceeds 5000 ppm, phase transition may not occur, and at the same time, the molecular weight of the obtained resin becomes too low, making it impossible to maintain strength, which is not preferable. The first reaction tank used in the present invention has a supply port for the raw material solution at the bottom of the reaction tank, has a built-in screw type stirring blade with a draft tube, and has an auxiliary stirring at the bottom of the reaction tank near the supply port for the raw material solution. It is equipped with wings. Such a reaction tank may be one that is generally widely used, for example, the
Those described in No. 29628 can also be used. Examples of the types of auxiliary stirring blades include a turbine type, a fan turbine type, and a propeller type. The auxiliary stirring blade may be coaxially joined to the screw-type stirring blade, or may be driven by being attached to a separate shaft using a separate power source. Such auxiliary stirring blades are important in producing products free of large particles of rubber components. When using the above reaction tank, the rotation speed N (rps) of the screw type stirring blade and the screw type stirring blade diameter φ
It is desirable that the relationship (m) be maintained to satisfy 0.15<N ²・φ<10.
If ^N2・φ≦0.15, giant particles may be generated during phase transition of the rubber component, stagnation may occur inside the reaction tank, or polymers may adhere during long-term operation. This causes a decrease in reaction volume and a decrease in heat transfer coefficient, which impairs stable operation. On the other hand, N ²・φ
Even if it exceeds 10, the stirring efficiency remains the same as when the value is lower than 10, and the stirring power is simply wasted. The particle size of the rubber component can be controlled to some extent by the value of N ² φ, and when N ² φ is 0.15 to 10
Within this range, the particle size can be adjusted to a desired range. In the present invention, it is appropriate to control the polymerization rate of the monomer in the first reaction tank within the range of 10 to 35% by weight. If the polymerization rate of the monomer in the first reaction tank is less than 10% by weight, the conversion rate of the monomer is too low to cause a phase transition, or even if the phase transition occurs, the generated dispersed particles will not be produced. It is undesirable because it is stable and condenses into giant particles. In addition, if the polymerization rate of the monomer in the first reaction tank exceeds 35% by weight, many large particles may be generated during phase transition, or in some cases, gelation may occur without phase transition. Undesirable. In the method of the present invention, the rubber-modified impact-resistant resin to be produced must be manufactured so that the volume average particle diameter of the dispersed particles of the rubber component is 1.5 to 10 μm. If the volume average particle size of the rubber component is less than 1.5 μm, the resulting molded product will have a glossy surface and must be processed in some way for matte purposes, which is not suitable for the purpose of the present invention. do not. Furthermore, if the volume average particle diameter of the rubber component exceeds 10 μm, it is not preferable because it contains many giant particles, resulting in a poor appearance of the resulting resin and a decrease in impact strength. Incidentally, the volume average particle diameter of the dispersed particles of the rubber component referred to in the present invention is measured as follows. That is, an electron micrograph is taken of the resin using an ultra-thin section method, and 100 to 200 dispersed particles of the rubber component in this photograph are
The particle diameters of each particle were measured and averaged using the following formula. Volume average particle size = 〓nD ⁴ /〓nD ³ (However, n is the number of dispersed particles of the rubber component with a particle size D.) Adjustment of the particle size of the dispersed particles of the rubber component is performed using (A) to (F). This can be achieved by selecting the optimal combination while satisfying the following conditions. In particular, by optimally selecting the conditions (D) to (F) within the above range, the particle size can be easily adjusted. In this way, a raw material solution in which a rubber component is dissolved in a mixture of an aromatic vinyl monomer and a vinyl cyanide monomer and a chain transfer agent are continuously supplied to the first reaction tank, and the desired amount is obtained in the first reaction tank. The reaction solution obtained by polymerizing the monomer under stirring shear force to obtain dispersed rubber molecular particles with a particle size is continuously extracted from the reaction tank in an amount equivalent to the total supply amount, and then It is supplied to the second and subsequent reaction vessels, and polymerization is continued. There are no particular restrictions on the second and subsequent reaction tanks used here, and reaction tanks generally used for bulk or solution polymerization can be used, but preferably a complete mixing tank type reaction tank or a piston flow type reaction tank. A tubular or tower reactor, or a combination thereof, is preferred. Moreover, the number of reaction tanks after the second tank is usually about 1 to 5. Usually, a method is adopted in which monomer polymerization is continued in the second and subsequent reaction vessels, and the reaction liquid that has been polymerized to a desired polymerization rate is continuously extracted from the final reaction vessel. The reaction solution obtained from the final reaction tank is used in a conventionally known devolatilization device to remove unreacted monomers and solvent, and then the polymer is recovered to form a resin product. The raw material solution used in the present invention may be only a monomer mixture and a rubber component, but if necessary, it may contain aromatic hydrocarbons, aliphatic hydrocarbons, alicyclic hydrocarbons, halogenated hydrocarbons, ketones, etc. A solvent may be used in an amount of 40% by weight or less. When the amount of the solvent exceeds 40% by weight, the effect of chain transfer due to the solvent is observed, and the diameter of the dispersed particles of the rubber component may not be able to be controlled. This is also preferable since production efficiency also decreases. Furthermore, if necessary, antioxidants such as alkylated phenols, plasticizers or lubricants such as butyl stearate, zinc stearate, and mineral oil may be added to the raw material solution, or during or at the end of polymerization. It's okay. Further, in the present invention, it is possible to carry out sufficient polymerization without using a polymerization catalyst, but if necessary, a radical polymerization initiator such as benzoyl peroxide may be used as a catalyst to carry out the polymerization. According to the method of the present invention, the equipment used to produce HI-PS by continuous bulk or solution polymerization, which is widely used, can be used without using complicated polymerization methods such as conventional emulsion polymerization methods. , it is possible to obtain ABS resin that becomes a matte product when molded into a molded product without any secondary processing. Also, obtained
The physical properties of ABS resin are similar to conventional high-gloss ABS resin, except that it is matte.
It exhibits good tensile strength, etc., and furthermore, there are no large rubber particles found in conventional dull resins. Furthermore, in the method of the present invention, it is possible to almost completely prevent the polymer containing the rubber component from adhering to the inner wall of the reaction tank. As described above, the method of the present invention can be used as is without secondary processing in fields where matte products, which have traditionally required time and effort, have been required as the use of ABS resin expands. can do
Since it provides ABS resin and the polymerization process is more efficient than conventional methods, its industrial value is extremely large. The present invention will be explained below with reference to Examples. In addition,
In the following, % and parts indicate weight % and parts by weight, respectively. Example 1 7.0 parts of polybutadiene, "Asaprene 700A"
(trade name, manufactured by Asahi Kasei Corporation), 54.7 parts of styrene,
A raw material solution was prepared by dissolving in a mixed solution of 18.3 parts of acrylonitrile (amount of monomeric acrylonitrile, 25.1%) and 20.0 parts of ethylbenzene. The solution viscosity of a 5% styrene solution of Asaprene 700A at 30°C is 45 centistokes. After adding 0.15 parts of tertiary dodecyl mercaptan and 0.20 parts of 2,6-di-tert-butylphenol as an antioxidant to this raw material solution, a screw-type stirring blade with a draft tube was installed and an auxiliary stirring blade was attached to the bottom of the stirring blade. was continuously supplied from the supply port at the bottom to the first reaction tank containing the reactor at a rate of 15.0/hr. The volume of the first reaction tank is 18.0, and the outer diameter of the screw type stirring blade is 0.18 m. In the first reaction tank, polymerization was carried out at a stirring blade rotation speed of 2 rps and a temperature of 130° C. to cause a phase transition of the rubber component and generate rubber particles. The reaction solution obtained by polymerization in the first reaction tank was continuously extracted and supplied to the second reaction tank to continue polymerization. The polymerization rate of the monomer in the first reaction tank was 23%. The second reaction tank is equipped with the same screw-type stirring blade with a draft tube as the first reaction tank, but
A complete mixing reactor without an auxiliary stirring blade at the bottom was used. Furthermore, the reaction liquid polymerized in the second reaction tank is continuously extracted and sequentially supplied to the third, fourth, and fifth reaction tanks, so that the polymerization rate of the monomer in the fifth reaction tank is 70%.
Polymerization was continued so that 3rd, 4th, 5th
The same type of reaction tank as the second reaction tank was also used. The reaction liquid continuously obtained from the fifth reaction tank is
After removing unreacted monomers and solvent under high temperature and high vacuum using a devolatilization device, the product was pelletized using an extruder to obtain an ABS resin product. The volume average particle diameter of the dispersed particles of the rubber component in the obtained product was adjusted to 2.6 μm. In addition, the obtained product was molded into a test piece using a 4-ounce injection molding machine, and its physical properties were evaluated. The evaluation results are shown in Table 1 (the evaluation results for the following examples are also summarized in Table 1). Regarding gloss, JIS
- Measured at an incident angle of 60° according to Z-8751. When the measured value shows a value of 30% or less, it is preferable as a matte product, and when the measured value shows a value of 20% or less, it is judged to be extremely excellent. Example 2 Styrene-butadiene copolymer “Tufden 2000A” (trade name, Asahi Kasei Co., Ltd.) was used as the rubber component of the raw material solution.
Polymerization was carried out in the same manner as in Example 1, except that a 5% styrene solution (viscosity at 30°C of 50 centistokes manufactured by Co., Ltd.) was used. Example 3 Polymerization was carried out in the same manner as in Example except that polybutadiene "NF35A" (trade name, manufactured by Asahi Kasei Corporation, viscosity of 5% styrene solution at 30°C: 85 centistokes) was used as the rubber component of the raw material solution. carried out. Example 4 The weight ratio of acrylonitrile in the raw material solution monomer was 41% (styrene 43.1 parts, acrylonitrile 29.9 parts).
Polymerization was carried out in the same manner as in Example 1, except that the polymerization temperature in the first reaction tank was 128°C. However, the composition of unreacted styrene/acrylonitrile at the inlet of each of the second to fifth reaction tanks is 59/41.
In order to adjust the weight ratio, styrene was continuously added from the inlet of each reaction tank. Example 5 The amounts of rubber components in the raw material solution were changed to 9.0 parts, styrene to 53.2 parts, acrylonitrile to 17.8 parts, and ethylbenzene to 20.0 parts, the polymerization temperature in the first reaction tank to 128°C, and the stirring blade Polymerization was carried out in the same manner as in Example 1, except that the rotation speed was 3 rps. The polymerization rate of the monomer in the first reaction tank was 20%. Example 6 Polymerization was carried out in the same manner as in Example 1, except that the rotation speed of the stirring blade in the first reaction tank was changed to 3 rps. The gloss of the molded product obtained was slightly higher than that of Example 1, at 20%. Example 7 Polymerization was carried out in the same manner as in Example 1, except that the second to fifth reaction vessels were replaced with four commonly used piston flow type column reaction vessels. The product obtained was almost equivalent to that of Example 1. Comparative Example 1 Using the same equipment as in Example 1, as a raw material solution
Dissolve 7.0 parts of polybutadiene "Asaprene 700A" in 78.0 parts of styrene and 15.0 parts of ethylbenzene,
Add 0.20 parts of 2,6-ditertiarybutylphenol as an antioxidant, and add 12.0 parts of 2,6-ditertiarybutylphenol to the first reaction tank.
/hr, and polymerization was carried out at 145°C.
The polymerization rate of the monomer in the first tank was 22% by weight.
Polymerization in the second and subsequent reactors was carried out so that the polymerization rate of the monomer in the fifth reactor was 73% by weight. The impact resistance, rigidity, heat resistance, etc. of the obtained product were as shown in Example 1.
It was inferior to the ABS resin obtained in The evaluation results are shown in Table 2. Evaluation results for the following comparative examples are also summarized in Table 2. All molding conditions etc. are the same as Example 1.
is the same as Comparative Example 2 The amount of acrylonitrile in the raw material solution monomer was 60
% (styrene 29.2 parts, acrylonitrile 43.8 parts)
Next, polymerization was carried out in the same manner as in Example 4, except that the amount of tertiary dodecyl mercaptan was changed to 0.30 parts and the polymerization temperature of the first reaction tank was changed to 125°C.
As a result, although heat resistance and rigidity increased, fluidity and impact resistance were low, and a product with a strong yellow tinge was obtained. Comparative Example 3 Polymerization was carried out in the same manner as in Example 1, except that polybutadiene "Diene NF55A" was used as the rubber component in the raw material solution, and the rotation speed of the stirring blade in the first reaction tank was set to 6 rps. As a result, the viscosity of the reaction solution increased and became gel-like before the phase transition occurred in the first reaction tank, and a normal product could not be obtained. Comparative Example 4 The amount of rubber in the raw material solution was 16.0 parts, 48.0 parts of styrene,
Polymerization was carried out in the same manner as in Example 1, except that 16.0 parts of acrylonitrile and 20.0 parts of ethylbenzene were used, and the rotation speed of the stirring blade in the first reaction tank was changed to 6 rps. As a result, the viscosity of the reaction solution increased and became gel-like before the phase transition occurred in the first reaction tank, and a normal product could not be obtained. Comparative Example 5 Same as Example 1 except that the molecular weight was adjusted by stopping the addition of tertiary dodecyl mercaptan to the raw material solution and continuously adding tertiary dodecyl mercaptan only to the second reaction tank. Polymerization was carried out using As a result, the resulting molded product showed an increase in gloss and a decrease in impact strength. Comparative Example 6 Polymerization was carried out in the same manner as in Example 1, except that the rotation speed of the stirring blade in the first reaction tank was changed to 0.5 rps. Although large rubber particles were obtained through phase transition in the first reaction tank, they contained giant particles.
Further, since a stagnation portion was generated inside the reaction tank, the polymerization rate of the first reaction tank gradually decreased during long-term operation, making stable operation impossible. Comparative Example 7 Polymerization was carried out in the same manner as in Example 1 except that the polymerization temperature in the first reaction tank was 110°C. The polymerization rate of the monomer in the first reaction tank was 9%, and the reaction solution there did not undergo any phase transition. Comparative Example 8 Polymerization was carried out in the same manner as in Example 1, except that the polymerization temperature in the first reaction tank was 150° C. and the rotation speed of the stirring blade in the first reaction tank was 6 rps. As a result, the viscosity of the reaction solution increased and became gel-like before the phase transition occurred in the first reaction tank, and a normal product could not be obtained. When the polymerization rate of the reaction solution in the first reaction tank was measured, it was found to be 40
It was %. Comparative Example 9 Addition of 0.05 parts of tertiary dodecyl mercaptan to the raw material solution, and the rotation speed of the stirring blade in the first reaction tank
Polymerization was carried out in the same manner as in Example 1 except that the speed was changed to 6rps. The particle size of the obtained product was 1.0 μm, and the gloss of the molded product increased by 61%.

【table】

【table】

【table】

【table】

Claims (1)

[Claims] 1. Rubber is added to a monomer mixture of an aromatic vinyl monomer, a vinyl cyanide monomer, and optionally a monomer copolymerizable with these monomers. The raw material solution in which the components are dissolved is continuously supplied to the first reaction tank, and polymerized under stirring shear force to a polymerization rate necessary for converting the rubber component phase into dispersed particles. Continuous lumps of rubber-modified impact resistant resin are produced by continuously taking out an amount of reaction liquid corresponding to the amount supplied and further supplying this reaction liquid to the second reaction tank and subsequent reaction tanks to continue polymerization. In the solution polymerization method, (A) vinyl cyanide monomer in the monomer mixture is
(B) the raw rubber component is one whose 5% styrene solution at 30°C exhibits a viscosity of 150 centistokes or less; (C) the concentration of the rubber component in the raw material solution is 3. ~15% by weight
(D) One or two chain transfer agents are added to the first reaction tank.
Adding more than 1 species of mercaptans to the raw material solution,
100 to 5000 ppm is continuously supplied, (E) the first reaction tank is equipped with a screw-type stirring blade with a draft tube, and an auxiliary stirring blade is built in the bottom of the reaction tank, which is the supply part of the raw material solution, The rotational speed N (rps) of the screw type stirring blade in the reaction tank and the diameter φ (m) of the screw type stirring blade
(F) The polymerization rate of the monomer in the ^first reaction tank is controlled to be 10 to 35% by weight, and (G ) A continuous process of matte rubber-modified impact-resistant resin characterized in that the dispersed particles of the rubber component of the rubber-modified impact-resistant resin obtained are adjusted so that the volume average particle size is 1.5 to 10 μm. Production method. 2 The reaction tanks after the second tank are one to five complete mixing tank type reaction tanks, one to five piston flow type tubular or expansion reaction tanks, or a combination thereof. A manufacturing method according to claim 1.