JPH08151499A - Production of impact-resistant resin composition - Google Patents

Abstract

PURPOSE: To obtain an impact-resistant resin composition having well-balanced physical properties by adding a graft copolymer into a rubber-containing copolymer in a molten state produced by grafting a rubbery polymer with specified monomers each in a specified amount. CONSTITUTION: A rubber-containing copolymer (A) having a residual monomer content of at most 10wt.% is obtained by the continuous bulk polymerization of 1-25wt.% rubbery polymer, 99-40wt.% aromatic vinyl monomer, 0-60wt.% vinyl cyanide monomer, 0-80wt.% (meth)acrylic ester monomer, and 0-60wt.% other vinyl monomer and then removing remaining monomers. A graft copolymer (B) is obtained by the emulsion polymerization of 5-80wt.% rubbery polymer, 10-100wt.% aromatic vinyl monomer, 0-50wt.% vinyl cyanide monomer, 0-80wt.% (meth)acrylic ester monomer, and 0-60wt.% other vinyl monomer and then dewatering and drying the obtained slurry. The copolymer A in a molten state is mixed with the copolymer B in such a manner that the rubbery polymer content of the copolymer A is less than that of the copolymer B, and thereby an impact-resistant resin composition is obtained.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a method for producing an impact resistant resin composition. More specifically, the present invention relates to a method for producing an impact resistant resin composition which is excellent in color tone and physical properties balance between impact resistance and rigidity.

[0002]

2. Description of the Related Art Impact-resistant resins containing rubber components represented by ABS and high-impact polystyrene are resins having a good balance between various physical properties and molding processability.
It is used in a wide range of applications such as automobile parts, electric equipment parts and office equipment parts. These rubber component-containing impact resistant resins need to be graft-polymerized with the rubber component in order to exhibit sufficient mechanical properties, and the emulsion graft polymerization has hitherto been the production method. However, the emulsion polymerization method has a number of steps and a large number of auxiliary raw materials, resulting in high cost, and further, requires wastewater treatment. Therefore, in order to reduce the problems of such emulsion polymerization, a method of melt-blending the emulsion-polymerized high rubber-containing polymer and the polymer obtained by rubber-free suspension polymerization has been developed. Academic Society "AB
S resin "). Further, in recent years, a process for directly subjecting an impact resistant resin containing rubber to continuous bulk polymerization has been put into practical use (for example, Japanese Patent Publication No. 47-14136 and Japanese Patent Publication No. 49).
-26711, Chemical Engineering 53 (6) 423-42
6 (1989)).

[0003]

However, after obtaining emulsion-polymerized high rubber-containing polymer and polymer obtained by continuous bulk polymerization method or suspension polymerization containing no rubber as isolated polymers, respectively, The method of melt blending has the advantage that the physical properties can be controlled relatively smoothly, but wastewater treatment is required, and since the heat history is further received during melt blending, the color tone is not sufficient, impact resistance and rigidity and However, the physical property balance is not sufficient. On the other hand, a method of directly producing an impact-resistant resin containing a large amount of a rubber component by a continuous continuous bulk polymerization method is the most excellent in that it has few steps and auxiliary raw materials and does not require wastewater treatment. It has the drawback that the reaction is difficult to control. Further, it is not always satisfactory in physical properties such as impact resistance. In addition, when the amount of rubber component is large, there is a drawback in that a deteriorated product of the rubber stays in the device and is peeled off, which causes problems in manufacturing and quality.

[0004]

Means for Solving the Problems The present invention has been accomplished as a result of extensive studies on a method for producing an impact resistant resin composition having an excellent color tone and a balance of physical properties such as impact resistance and rigidity. That is, the present invention relates to 1 to 25% by weight of a rubber-like polymer, 99 to 40% by weight of an aromatic vinyl monomer, 0 to 60% by weight of a vinyl cyanide monomer, and a (meth) acrylic acid ester-based monomer. Rubber-containing copolymer (A) in a molten state during a continuous bulk polymerization process containing a rubber component in which 0 to 80% by weight of a monomer and 0 to 60% by weight of another vinyl-based monomer copolymerizable therewith are graft-polymerized. Aromatic vinyl monomer 10 in the presence of 5 to 80 parts by weight of a rubber-like polymer with respect to 1 to 99 parts by weight.
˜100% by weight, vinyl cyanide-based monomer 0-50% by weight and (meth) acrylic acid ester-based monomer 0-80
A slurry or hydrous cake obtained from a latex obtained by emulsion-grafting 95 to 20 parts by weight of a monomer mixture consisting of 0 to 60% by weight and 0 to 60% by weight of another vinyl-type monomer copolymerizable therewith is passed through a liquid material. 99 to 1 part by weight of the graft copolymer (B) dehydrated and dried by being supplied to an extruder having grooves, holes or gaps and vent holes to be used (however, from the graft copolymer (B) in the impact resistant resin composition). Rubber-like polymer content >> rubber-like polymer content from the rubber-containing copolymer (A)) is continuously added and mixed, and a method for producing an impact resistant resin composition is provided. To do.

The aromatic vinyl monomer constituting the rubber-containing copolymer (A) and the graft copolymer (B) used in the present invention is an aromatic compound having a polymerizable double bond. As examples, styrene, α-methylstyrene,
Examples thereof include p-methylstyrene, vinyltoluene, propylstyrene, butylstyrene and cyclohexylstyrene. These aromatic vinyl monomers are used alone or as a mixture of two or more. Of these aromatic vinyl monomers, styrene and α-methylstyrene are particularly preferably used.

The vinyl cyanide-based monomer constituting the rubber-containing copolymer (A) and the graft copolymer (B) used in the present invention is a compound having a polymerizable double bond and a cyano group. There are acrylonitrile and methacrylonitrile as specific examples. These vinyl cyanide-based monomers are used alone or in a mixture of two or more. Of these vinyl cyanide-based monomers, acrylonitrile is particularly preferably used.

Specific examples of the (meth) acrylic acid ester type monomers constituting the rubber-containing copolymer (A) and the graft copolymer (B) used in the present invention include methyl methacrylate, ethyl methacrylate, Propyl methacrylate,
Examples thereof include butyl methacrylate, glycidyl methacrylate, hydroxyethyl methacrylate, methyl acrylate, ethyl acrylate, propyl acrylate and butyl acrylate. These (meth) acrylic acid ester-based monomers are used alone or as a mixture of two or more.
Of these (meth) acrylic acid ester-based monomers, methyl methacrylate is particularly preferably used.

The other vinyl monomers constituting the rubber-containing copolymer (A) and the graft copolymer (B) used in the present invention are, for example, N-phenylmaleimide, N-cyclohexylmaleimide, methyl-substituted N- Examples thereof include phenylmaleimide, maleic anhydride, acrylic acid and methacrylic acid. Among them, N-phenylmaleimide is particularly preferably used.

The rubber-like polymer constituting the rubber-containing copolymer (A) and the graft copolymer (B) used in the present invention is a diene rubber, an acrylic rubber, an ethylene rubber or the like. Examples include polybutadiene, poly (butadiene-styrene), poly (butadiene-acrylonitrile), polyisoprene, poly (butadiene-butyl acrylate), poly (butadiene-methyl acrylate), poly (butadiene-methyl methacrylate), poly (butadiene-methyl methacrylate), (Butadiene-ethyl acrylate), ethylene-propylene rubber, ethylene-propylene-diene rubber, poly (ethylene-isobutylene), poly (ethylene-methyl acrylate), poly (ethylene-methyl acrylate)
And the like. These rubbery polymers are used in one kind or a mixture of two or more kinds. Among these rubber-like polymers, polybutadiene, poly (butadiene-styrene), poly (butadiene-acrylonitrile) and ethylene-propylene rubber are particularly preferably used.

Preferred examples of the rubber-containing copolymer (A) used in the present invention are butadiene-styrene copolymer, butadiene-styrene-acrylonitrile copolymer, butadiene-styrene-N-phenylmaleimide copolymer,
Butadiene-styrene-acrylonitrile-methyl methacrylate copolymer, butadiene-styrene-methyl methacrylate copolymer, ethylene-propylene-styrene-
Acrylonitrile graft copolymers are mentioned, and among them, butadiene-styrene-acrylonitrile copolymers are particularly used.

Preferred examples of the graft copolymer (B) used in the present invention include styrene graft polymer of polybutadiene, styrene graft polymer of poly (butadiene-styrene), styrene-acrylonitrile graft copolymer of polybutadiene, and poly ( Butadiene-styrene)
Styrene-acrylonitrile graft copolymer, poly (butadiene-acrylonitrile) styrene-acrylonitrile graft copolymer, polybutadiene styrene-acrylonitrile-methyl methacrylate graft copolymer, poly (ethylene-propylene) styrene-acrylonitrile graft copolymer Examples thereof include polymers. Above all, the rubber of the rubber-containing copolymer (A) and the use ratio of each monomer are, in particular, the mechanical strength of the obtained resin composition,
From the viewpoint of color tone and moldability, 1 to 25% by weight of a rubbery polymer, 99 to 40% by weight of an aromatic vinyl monomer, 0 to 60% by weight of a vinyl cyanide monomer, and (meth) acrylic acid. This is to graft-polymerize 0 to 80% by weight of an ester monomer and 0 to 60% by weight of another vinyl monomer copolymerizable therewith. Preferably rubbery polymer 1
To 50% by weight of aromatic vinyl monomer 99 to 50% by weight, vinyl cyanide monomer 0 to 50% by weight, (meth)
Acrylic ester type monomer is 0 to 70% by weight and other vinyl type monomer copolymerizable with these is 0 to 50% by weight, more preferably 1 to 15% by weight of rubber-like polymer.
To 99 to 55% by weight of aromatic vinyl-based monomer, 10 to 40% by weight of vinyl cyanide-based monomer, 0 to 60% by weight of (meth) acrylic acid ester-based monomer, and others copolymerizable with these The vinyl monomer is from 0 to 40% by weight.

The first half of the present invention, that is, 1 to 25% by weight of the rubbery polymer, the aromatic vinyl monomer 99 to 40
% By weight, 0 to 60% by weight of vinyl cyanide-based monomer, 0 to 80% by weight of (meth) acrylic acid ester-based monomer, and 0 to 60 of other vinyl-based monomer copolymerizable with them.
There is no limitation on the continuous bulk polymerization method in the step of continuously bulk polymerizing the rubber-containing copolymer (A) which is graft-polymerized by weight%, and any continuous bulk polymerization method can be adopted. For example, after polymerizing in the polymerization tank, demonomerization (devolatilization)
It is known how to do it. As the polymerization tank, various stirring blades such as paddle blades, turbine blades, propeller blades,
A mixing type polymerization tank having a bull margin blade, a multistage blade, an anchor blade, a Maxblend blade, a double helical blade, or the like, or various tower type reactors can be used. Furthermore, a multi-tube reactor, a kneader type reactor, a twin-screw extruder or the like can also be used as a polymerization reactor (for example, Assessment of Polymer Manufacturing Process 10 “Attack of High Impact Polystyrene”: Polymer Society of Japan). , 1989
January 26, etc.). These polymerization tanks (reactors) are 1
It may be used in a group (tank) or in two or more (tank) or more, and may also be used in combination of two or more kinds of reactors as required.

The reaction mixture of the rubber-containing copolymer (A) polymerized in these polymerization tanks or reactors is usually then subjected to a demomerization step to remove monomers and other volatile components. Demonomerization methods include a uniaxial or twin-screw extruder with a vent that removes volatile components from the vent holes under atmospheric pressure or reduced pressure while heating, and a plate fin type heater such as a centrifugal type is incorporated in the drum for evaporation. Method to remove volatile components with a vessel, method to remove volatile components with a thin film evaporator such as a centrifugal type, method to remove residual heat with a multi-tube heat exchanger, foam and flash into a vacuum tank to remove volatile components Although any method can be used, a single-screw or twin-screw extruder having a vent is preferably used.

The continuous bulk polymerization of the rubber-containing copolymer (A) can be carried out by thermal polymerization without using an initiator, by initiator polymerization with an initiator, and further by thermal polymerization and initiator polymerization. It is also possible to use together. A peroxide or an azo compound is used as the initiator.

Specific examples of the peroxide include benzoyl peroxide, cumene hydroperoxide, dicumyl peroxide, diisopropylbenzene hydroperoxide, t-butyl hydroperoxide and t.
-Butyl cumyl peroxide, t-butyl peroxyacetate, t-butyl peroxybenzoate, t-
Butyl peroxyisopropyl carbonate, G-t-
Butyl Peroxide, t-Butyl Per Octate, 1,
1-bis (t-butylperoxy) 3,3,5-trimethylcyclohexane, 1,1-bis (t-butylperoxy) cyclohexane, t-butylperoxy-2-ethylhexanoate and the like can be mentioned. Among them, cumene hydroperoxide and 1,1-bis (t-butylperoxy) 3,3,5-trimethylcyclohexane are particularly preferably used. Specific examples of the azo compounds include azobisisobutyronitrile, azobis (2,4dimethylvaleronitrile), 2-phenylazo-2,4-
Dimethyl-4-methoxyvaleronitrile, 2-cyano-
2-Propylazoformamide, 1,1'-azobiscyclohexane-1-carbonitrile, azobis (4-methoxy-2,4-dimethylvaleronitrile), dimethyl 2,2'-azobisisobutyrate, 1-t -Butylazo-1-cyanocyclohexane, 2-t-butylazo-
2-cyanobutane, 2-t-butylazo-2-cyano-
4-methoxy-4-methylpentane and the like can be mentioned.
When these initiators are used, they may be used alone or in combination of two or more. Among them, 1,1'-azobiscyclohexane-1-carbonitrile is particularly preferably used.

A chain transfer agent such as mercaptan or terpene may be used for the purpose of controlling the degree of polymerization of the rubber-containing copolymer (A) used in the present invention. Specific examples thereof include n-octyl mercaptan, Examples thereof include t-dodecyl mercaptan, n-dodecyl mercaptan, n-tetradecyl mercaptan, n-octadecyl mercaptan and terpinolene. When these chain transfer agents are used, they may be used alone or in combination of two or more.
Among them, n-octyl mercaptan, t-dodecyl mercaptan and n-dodecyl mercaptan are particularly preferably used.

The rubber-containing copolymer (A) used in the present invention is produced by a continuous bulk polymerization method, but it is also possible to polymerize using a small amount of solvent (for example, 20% or less). It is included in the scope of the invention. Further, in order to prevent deterioration of rubber, various antioxidants such as phenol-based, phosphorus-based and sulfur-based antioxidants can be added to the polymerization tank. Among them, phenol-based antioxidants are preferable, for example, n-octadecyl 3 (3 ′, 5′-Di-t-butyl-4-hydroxyphenyl) propionate and 4,4′-butylidenebis (3-methyl-4-hydroxy-5-methylphenyl) propionate are particularly preferable.

The other component used in the present invention, the graft copolymer (B), is a rubber-like polymer 5 to 80.
10 to 100% by weight of the aromatic vinyl monomer,
A unit consisting of 0 to 50% by weight of a vinyl cyanide monomer, 0 to 80% by weight of a (meth) acrylic acid ester monomer, and 0 to 60% by weight of another vinyl monomer copolymerizable therewith. It is a copolymer obtained by graft-polymerizing 95 to 20 parts by weight of the monomer mixture, but it is not necessary that the entire amount be grafted, and normally, the one obtained as a mixture with the ungrafted copolymer is used. To do. The graft ratio of the graft copolymer (B) is not limited, but preferably 5 to 1
50%, more preferably 10 to 100% by weight is used. The graft ratio here is calculated by the following equation. Graft ratio (% by weight) = (weight of graft branch / weight of rubber-like polymer) × 100

The proportion of the rubber-like polymer in the graft copolymer (B) is 5 to 80 parts by weight, more preferably 20 to 20 parts by weight, from the viewpoint of mechanical strength, color tone and moldability of the resulting resin composition. 70 parts by weight. Graft copolymer (B)
The ratio of each monomer other than the rubber-like polymer used is 10 to 100% by weight of an aromatic vinyl-based monomer, 0 to 50% by weight of a vinyl cyanide-based monomer, and a (meth) acrylic acid ester-based monomer. 0 to 80% by weight of monomers and 0 to 60% by weight of other vinyl monomers copolymerizable therewith, and more preferably (1) 60 to 100% by weight of aromatic vinyl monomers, cyanated Vinyl monomer 10 to 40% by weight and (meth)
Acrylic ester-based monomer 0% by weight, or (2) aromatic vinyl-based monomer 20 to 60% by weight, vinyl cyanide-based monomer 0 to 30% by weight, and (meth) acrylic acid ester-based monomer The body is 40 to 80% by weight.

The method for producing the graft copolymer (B) is not limited, but it is preferably produced by emulsion polymerization or bulk polymerization, and more preferably emulsion polymerization. Emulsion polymerization is usually emulsion graft polymerization of a monomer mixture in the presence of a rubbery polymer latex. The emulsifier used in this emulsion graft polymerization is not particularly limited, and various surfactants can be used, but anionic surfactants such as carboxylate type, sulfate ester type, and sulfonate type are particularly preferably used. It Specific examples of such emulsifiers include caprylate, caprate, laurate, mistyrate, palmitate, stearate, oleate,
Linoleate, linolenate, rosinate, behenate, castor oil sulfate, lauryl alcohol sulfate, other higher alcohol sulfate, dodecylbenzenesulfonate, alkylnaphthalenesulfonate, alkyldiphenyl Examples thereof include ether disulfonate, naphthalene sulfonate condensate, dialkyl sulfosuccinate, polyoxyethylene lauryl sulfate, polyoxyethylene alkyl ether sulfate, and polyoxyethylene alkylphenyl ether sulfate. The salt referred to here is an alkali metal salt, an ammonium salt, and the like, and specific examples of the alkali metal salt include a potassium salt, a sodium salt, a lithium salt, and the like. These emulsifiers are used alone or in combination of two or more. In addition, examples of the initiator and chain transfer agent that can be used in these emulsion graft polymerizations include the initiators and chain transfer agents mentioned in the production of the copolymer (A), and the initiator can also be used in a redox system.

The graft copolymer (B) produced by emulsion graft polymerization is then added with a coagulant to coagulate the latex and recover the graft copolymer (B). An acid or a water-soluble salt is used as the coagulant, and specific examples thereof include
Examples thereof include sulfuric acid, hydrochloric acid, phosphoric acid, acetic acid, calcium chloride, magnesium chloride, barium chloride, aluminum chloride, magnesium sulfate, aluminum sulfate, ammonium ammonium sulfate, potassium aluminum sulfate, and sodium aluminum sulfate. These coagulants are used in one kind or a mixture of two or more kinds. The solidified slurry or water-containing cake-like graft copolymer (B) is supplied to an extruder having a groove / hole or gap for allowing a liquid material to pass therethrough and a vent hole to be dehydrated / dried. This dehydration
The extruder for drying is composed of a screw, a cylinder, and a screw driving unit, and the cylinder preferably has a heating / cooling capacity. The cylinder has grooves, holes or gaps that allow liquids to pass through in the first half (supply side) but does not allow most solids to pass through, and one or more vent holes in the second half (discharge side). There may be a single screw extruder or a twin screw extruder. The slurry or hydrous cake-like graft copolymer (B) is supplied to the present extruder and compressed by rotating the screw in the low temperature region (first half) of the cylinder to compress most of the water in the first half (supply side) of the cylinder. Of the rubber-containing copolymer (A) continuously discharged from the tip of the cylinder by removing the residual water and volatile components from the vent hole in the heating region in the latter half of the cylinder (discharging side). Supply to. The vent hole may be left at normal pressure or may be subjected to reduced pressure.
Normal pressure and reduced pressure may be used together in one or more vent holes.

As described above, the graft copolymer (B)
It is also possible to produce by a bulk polymerization method. In the case of production by a bulk polymerization method, it is possible to directly add the graft copolymer (B) in a molten state, which has come out of the demonomerizing machine, to the copolymer (A), or it is isolated in advance. Although it is possible to add the graft copolymer (B) to the copolymer (A), usually, the graft copolymer in a molten state discharged from the demonomerizing machine from the viewpoints of preventing thermal deterioration and continuing the process. It is more preferable to add (B) directly.

In the present invention, it is necessary to continuously add the graft copolymer (B) to the rubber-containing copolymer (A) in the molten state during the bulk polymerization process, and then to mix it. A resin composition having excellent impact resistance and the like can be obtained. At that time, 1 to 99 parts by weight of the rubber-containing copolymer (A) in the molten state is added to the graft copolymer (B).
It is necessary to continuously add 99 to 1 part by weight, more preferably, 30 to 95 parts by weight of the rubber-containing copolymer (A) and 70 to 5 parts by weight of the graft copolymer (B) are continuously added. Mix after addition. However, it is necessary to satisfy the rubber-like polymer content from the graft copolymer (B)> the rubber-like polymer content from the rubber-containing copolymer (A) in the impact resistant resin composition. When the rubber-like polymer content from the graft copolymer (B) is smaller than the rubber-like polymer content from the rubber-containing copolymer (A), it is not preferable in terms of color tone and impact resistance.

At this time, the graft copolymer (B) is preferably added such that the residual monomer amount is 10% or less, more preferably during or after the demonomer step of the bulk polymerization process of the rubber-containing copolymer (A). Is preferably 5% or less, because the rubber component is not deteriorated by the heat history during the subsequent demonomerization operation, and the color tone and impact resistance, which are the features of the present invention, are further improved. Further, in the present invention, the mixing after continuously adding the graft copolymer (B) to the rubber-containing copolymer (A) is carried out by melt mixing so that physical properties such as impact resistance are sufficiently expressed. Is also preferable. This melt mixing may be carried out at the time of addition mixing, or after the mixture is isolated, for example, at the time of melt molding.

The method for continuously adding the graft copolymer (B) is not particularly limited, and it can be added by any method. Usually, various kinds of feeders such as a belt type feeder, a screw type feeder, a single screw extruder and a twin screw extruder are used, but a single screw extruder and a twin screw extruder are particularly preferably used. It is preferable that these continuous addition devices can be quantified. Further, the continuous addition device has a heating device, and it is preferable to add the graft copolymer (B) in a semi-molten or molten state because the mixed state is improved. An extruder having a heating device or the like can be used for this purpose.

In the present invention, if necessary, various antioxidants such as phenol-based, phosphorus-based, and sulfur-based, weathering agents such as ultraviolet absorbers and light stabilizers, antistatic agents, ethylenebisstearylamide, It is also possible to add a lubricant such as metal soap, a plasticizer, a colorant, a filler, a reinforcing material such as glass fiber or carbon fiber, and a flame retardant.

[0027]

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these examples.
The percentages and parts used in this example are% by weight and parts by weight, respectively. In addition, the YI value of the pellets was measured using a color difference meter manufactured by Suga Test Instruments Co., Ltd.
Value) was measured. Also, Izod impact strength is ASTM
D256, tensile strength was measured according to ASTM 638.

Reference Example 1 (Graft copolymer cake (B-
1) Production method) Polybutadiene latex (average rubber particle diameter 0.3 μm)
m, gel content 85%) 60 parts (solid content conversion), pure water 20
0 part, sodium formaldehyde sulfoxylate 0.4 part, sodium ethylenediaminetetraacetate 0.1
Parts, ferrous sulfate (0.01 part) and sodium phosphate 0.1 part were charged into a reaction vessel, the temperature was adjusted to 65 ° C. after nitrogen replacement, and 30 parts of styrene, 10 parts of acrylonitrile and n-dodecyl mercaptan were stirred. 0.3 part of the mixture was continuously added dropwise over 4 hours. At the same time, a mixture of 0.25 parts of cumene hydroperoxide, 2.5 parts of sodium laurate as an emulsifier and 25 parts of pure water was continuously added dropwise over 5 hours, and after the addition was completed, the mixture was kept for 1 hour to carry out polymerization. Finished. The latex after the polymerization was coagulated with 1.5% sulfuric acid, then neutralized with an alkali, washed and centrifuged to prepare a graft copolymer cake (B-1). The graft ratio of the obtained graft copolymer cake (B-1) was 40%.

Reference Example 2 A graft copolymer (B-1) latex was produced in the same manner as in Reference Example 1. The latex was coagulated with 1.5% sulfuric acid and then neutralized with an alkali to prepare a graft copolymer slurry (B-2).

Reference Examples 3 to 9 (Production Method of Graft Copolymer Cake (B-3 to 9)) In the same manner as in Reference Example 1, styrene and other substances were present in the presence of various rubbery polymers shown in Table 1. The mixture with the vinyl monomer of was polymerized to prepare graft copolymers (B-3 to 9) having the composition shown in Table 1. The PBD in Table 1 is the same polybutadiene rubber as that used in Reference Example 1, SB.
R is a styrene / butadiene copolymer rubber consisting of 25% styrene and 75% butadiene, NBR is an acrylonitrile / butadiene copolymer rubber consisting of 25% acrylonitrile and 75% butadiene, EPDM is an iodine value of 23, and a Mooney viscosity of 60. Of ethylene / propylene / 5-
It represents an ethylidene-2-norbornene terpolymer rubber (ethylene / propylene = 68.5 / 31.5 molar ratio).

[0031]

[Table 1] Example 1 Polybutadiene latex (average rubber particle diameter 0.3 μm
m, gel content 85%) 70 parts (solid content conversion), pure water 20
0 part, sodium formaldehyde sulfoxylate 0.4 part, sodium ethylenediaminetetraacetate 0.1
Part, ferrous sulfate (0.01 part) and sodium phosphate 0.1 part were charged into a reaction vessel, the temperature was adjusted to 65 ° C. after nitrogen replacement, and 22.8 parts of styrene and acrylonitrile under stirring.
A mixture of 2 parts and 0.3 part of n-dodecyl mercaptan was continuously added dropwise over 4 hours. Simultaneously and in parallel, 5 parts of a mixture of 0.25 parts of cumene hydroperoxide, 2.5 parts of sodium laurate as an emulsifier and 25 parts of pure water were added.
Continuous dripping was carried out over a period of time, and after the dripping was completed, the polymerization was completed by maintaining for 1 hour to obtain a latex. After adding 25 parts of styrene to 5 parts of the solid content of this latex and stirring well,
0.3 part of magnesium sulfate was added. Only the white polymer / monomer phase (crumb) was taken out from the mixed solution, and 47.2 parts of styrene, 22.8 parts of acrylonitrile, 0.15 parts of n-dodecyl mercaptan and 0.03 part of cumene hydroperoxide were added and a uniform solution ( Raw material dope)
And Next, this raw material dope has a helical ribbon type stirring blade, a condenser and a stationary separator are directly connected to the upper part, and water is taken out of the polymerization system from the lower phase of the separator, and the upper phase From the above, only the monomer was extracted and continuously charged into a polymerization tank having a jacket designed to be refluxed into the polymerization tank, and the polymer concentration was controlled to be 75%. A twin screw extruder type feeder having a preheater, a demonomerizer, and a heating device connected in tandem to the barrel portion 1/3 of the tip of the demonomerizer for a polymerization reaction mixture having a polymer concentration of 75%, and a vent hole 2 It is continuously supplied to the axial extruder, and the residual monomer is evaporated and recovered under reduced pressure from the vacuum vent hole at 180 to 240 ° C.
No. 3, where the apparent polymerization rate is 99% or more of butadiene /
80 parts of styrene / acrylonitrile copolymer,
From a twin-screw type feeder, 0.5 parts of t-butylhydroxytoluene, which is a phenolic stabilizer, 0.5 part of tri (nonylphenyl) phosphite, which is a phosphorus stabilizer, and the graft copolymer prepared in Reference Example 1 were used. Combined cake (B-
1) 20 parts were dehydrated by a single-screw extruder having two vent holes, supplied in a semi-molten state, melt-kneaded, and then discharged in a strand form to obtain styrene-based resin composition pellets by a cutter. YI of the obtained styrene resin composition
The values were as shown in Table 2. In addition, injection-molded pieces of the obtained styrene resin composition were molded, and the physical properties were measured. The results are shown in Table 2. As can be seen from Table 2, the styrene resin composition produced by the method of the present invention had excellent color tone and physical properties.

Example 2 Instead of the graft copolymer cake (B-1) used in Example 1, the graft copolymer slurry prepared in Reference Example 2 (B
Styrene-based resin composition pellets were obtained in the same manner as in Example 1 except that -2) was dehydrated and supplied by a single-screw extruder having two gaps for allowing water to pass through and two vent holes. The YI value of the obtained styrene resin composition was as shown in Table 2. In addition, injection-molded pieces of the obtained styrene-based resin composition were molded and the physical properties were measured.
It was shown to. As can be seen from Table 2, the styrene resin composition produced by the method of the present invention had excellent color tone and physical properties.

Examples 3 to 9 The graft copolymer cake (B-1) prepared in Reference Example 3 to 9 was used as the graft copolymer cake (B-1) in Example 1.
The procedure was performed in the same manner as in Example 1 except that the procedure was changed to 9) to obtain styrene resin composition pellets. Table 2 shows the YI value of the obtained styrene resin composition and the measurement results of the physical properties of the test pieces obtained by injection molding the resin composition. As can be seen from Table 2, the styrene resin composition produced by the method of the present invention had excellent color tone and physical properties.

Comparative Example 1 A polybutadiene-styrene-acrylonitrile graft copolymer latex was obtained in the same manner as in Example 1. After 43.4 parts of styrene was added to 42.9 parts of the solid content of this latex and stirred well, 0.3 part of magnesium sulfate was added. Only the white polymer / monomer phase (crumb) was taken out from the mixed solution, and 13.7 parts of acrylonitrile, n
-Dodecyl mercaptan 0.15 part and cumene hydroperoxide 0.03 part were added to make a uniform solution (raw material dope). Next, this raw material dope has a helical ribbon-type stirring blade, and a condenser and a stationary separator are directly connected to the upper part, and water is taken out of the polymerization system from the lower phase of the separator, and then from the upper phase. Was continuously charged into a polymerization tank having a jacket in which only the monomer was extracted and refluxed to the polymerization tank, and the polymer concentration was controlled to be 75%. The polymerization reaction mixture having a polymer concentration of 75% is equipped with a preheater, a demonomer, and a twin screw extruder type feeder having a heating device connected in tandem to the barrel portion 1/3 from the tip of the demonomer, and a vent hole 2 It is continuously fed to a shaft extruder and the residual monomer is evaporated and recovered under reduced pressure from a vacuum vent hole at 180 to 240 ° C., and butadiene with an apparent polymerization rate of 99% or more is obtained at 1/3 from the tip of the demonomer. To 70 parts of styrene / styrene / acrylonitrile copolymer, 0.5 part of t-butylhydroxytoluene, which is a phenolic stabilizer, and tri (nonylphenyl) phosphite, which is a phosphorus stabilizer, from a twin-screw extruder type feeder. .5
Parts and 30 parts of the graft copolymer cake (B-1) produced in Reference Example 1 were dehydrated by a single-screw extruder equipped with two vent holes, fed in a semi-molten state, melt-kneaded, and then strand-shaped. And a styrene resin composition pellet was obtained by a cutter. The YI value of the obtained styrene-based resin composition is as shown in Table 2, and injection-molded pieces of the styrene-based resin composition were molded and the physical properties were measured. The results are shown in Table 2. As can be seen from Table 2, the styrene resin composition produced by the method of this comparative example is superior in Izod impact strength to that produced by the method of the present invention, but is inferior in tensile strength and pellet color tone (pellet YI). There is.

Comparative Example 2 A polybutadiene-styrene-acrylonitrile graft copolymer latex was obtained in the same manner as in Example 1. After 25 parts of styrene was added to 15 parts of the solid content of this latex and stirred well, 0.3 part of magnesium sulfate was added, and only a white polymer / monomer phase (crumb) was taken out from the mixed solution. Division, acrylonitrile 2
0.4 parts, 0.15 part of n-dodecyl mercaptan and 0.03 part of cumene hydroperoxide were added to obtain a uniform solution (raw material dope). Next, this raw material dope has a helical ribbon type stirring blade, and is directly connected to the upper part to install a condenser and a stationary separator, and water is taken out of the polymerization system from the lower phase of the separator and the upper phase is empty. Was continuously charged into a polymerization tank having a jacket in which only the monomer was extracted and refluxed into the polymerization tank, and the polymer concentration was controlled to be 75%. A polymerization reaction mixture having a polymer concentration of 75% is provided with a preheater, a demonomer, and a twin screw extruder type feeder having a heating device connected in tandem to a barrel portion 1/3 from the tip of the demonomer and a vent hole 2 It is continuously fed to a shaft extruder and the residual monomer is evaporated and recovered under reduced pressure from a vacuum vent hole at 180 to 240 ° C., and butadiene with an apparent polymerization rate of 99% or more is obtained at 1/3 from the tip of the demonomer. / Styrene / acrylonitrile copolymer 9
For 0 parts, from a twin-screw extruder type feeder, t-butylhydroxytoluene 0.5 which is a phenolic stabilizer is used.
Part, 0.5 part of a phosphorus-based stabilizer, tri (nonylphenyl) phosphite, and 10 parts of the graft copolymer cake (B-1) produced in Reference Example 1, provided with two vent holes. Was dehydrated and supplied in a semi-molten state, melt-kneaded, and then discharged in a strand form, and a styrene-based resin composition pellet was obtained by a cutter. The YI value of the obtained styrene-based resin composition is as shown in Table 2, and the results of measuring the physical properties by molding an injection-molded piece of the styrene-based resin composition are shown in Table 2. As can be seen from Table 2, the styrenic resin composition produced by the method of this comparative example has a color tone (pellet T
I) is inferior.

Comparative Example 3 Styrene 7 was produced using the same continuous bulk polymerization apparatus as in Example 1.
A monomer mixture consisting of 6 parts, 24 parts of acrylonitrile and 0.15 part of t-butyl mercaptan was continuously charged into a polymerization tank and controlled so that the polymer concentration became 75%. A polymerization reaction mixture having a polymer concentration of 75% was preheated by a single-screw extruder type preheater as in Example 1, and then unreacted monomers were distilled and recovered from a vent port by a twin-screw extruder type demonomer. A styrene copolymer (A) pellet containing no rubber was obtained by discharging in a strand form and using a cutter. Next, 74 parts of this styrene-based copolymer (A) containing no rubber, 26 parts of powder obtained by drying the graft copolymer cake (B-1) produced in Reference Example 1, t
-Butyl hydroxytoluene (0.5 parts) and tri (nonylphenyl) phosphite (0.5 parts) were dry blended, and then melt-kneaded / extruded and pelletized to obtain styrene resin composition pellets. Table 2 shows the YI value of the styrene resin composition pellets and the results of measuring the physical properties of the molded pieces obtained by injection molding the resin composition. The color tone (pellet YI) of the styrene resin composition produced in this comparative example is clearly inferior to that of the example.

Comparative Example 4 Styrene / acrylonitrile copolymer beads 74 obtained by polymerizing a monomer mixture consisting of 76 parts of styrene, 24 parts of acrylonitrile and 0.18 part of t-dodecyl mercaptan by suspension polymerization, dehydrated and dried. Part, 26 parts of powder obtained by drying the graft copolymer cake (B-1) produced in Reference Example 1, 0.5 part of t-butylhydroxytoluene and 0.5 part of tri (nonylphenyl) phosphite are dry blended. After that, melt kneading / extrusion pelletization was performed to obtain styrene resin composition pellets. Table 2 shows the YI value of the styrene resin composition pellets and the physical property measurement results of molded pieces obtained by injection molding the styrene resin composition.
It was shown to. The color tone (pellet YI) of the styrene resin composition produced in this comparative example is clearly inferior to that of the example.

[0038]

[Table 2]

[0039]

INDUSTRIAL APPLICABILITY According to the present invention, a resin containing a small amount of a comb component is produced by a continuous bulk polymerization method, and a graft copolymer cake containing a rubber component is added at the time when the resin is in a molten state in the latter half of the demonomerization step. Alternatively, it is characterized in that the slurry is dehydrated and dried, and then added and mixed. Therefore, Example 1
A resin composition excellent in color tone and mechanical strength as shown in No. 9 can be obtained. Further, by adopting the manufacturing method of the present invention, it becomes possible to reduce the amount of wastewater treatment, and further, the number of manufacturing steps is small and the manufacturing cost can be reduced.

 ─────────────────────────────────────────────────── ─── Continued Front Page (72) Inventor Keiji Nakagawa 2-1, Chikusaigan, Ichihara-shi, Chiba Toray Co., Ltd. Chiba factory

Claims (7)

[Claims] 1. A rubber-like polymer in an amount of 1 to 25% by weight, an aromatic vinyl monomer in an amount of 99 to 40% by weight, a vinyl cyanide monomer in an amount of 0 to 60% by weight, and a (meth) acrylic acid ester type monomer. Rubber-containing copolymer (A) in a molten state during a continuous bulk polymerization process containing a rubber component in which 0 to 80% by weight of a monomer and 0 to 60% by weight of another vinyl-based monomer copolymerizable therewith are graft-polymerized. Aromatic vinyl monomer 1 in the presence of 5 to 80 parts by weight of a rubber-like polymer based on 1 to 99 parts by weight.
0 to 100% by weight, vinyl cyanide-based monomer 0 to 50% by weight, and (meth) acrylic acid ester-based monomer 0 to 8
A monomer mixture 95 to 20 consisting of 0% by weight and 0 to 60% by weight of another vinyl-based monomer copolymerizable therewith
Graft copolymer (B) 99 to which the slurry or hydrous cake obtained from the latex obtained by emulsion-polymerizing parts by weight is supplied to an extruder having grooves, holes or gaps for allowing a liquid to pass and dehydrated and dried. 1 part by weight (however, rubber-like polymer content from the graft copolymer (B) in the impact-resistant resin composition> rubber-like polymer content from the rubber-containing copolymer (A)) is continuously added. A method for producing an impact resistant resin composition, comprising: 2. The impact-resistant resin composition according to claim 1, wherein the graft copolymer (B) is continuously added to the rubber-containing copolymer (A) having a residual monomer content of 10% by weight or less. Method. 3. A rubber-containing copolymer (A) having a residual monomer content of 10% by weight or less during or after the demonomer step of continuous bulk polymerization of the rubber-containing copolymer (A). The method for producing an impact resistant resin composition according to claim 1, wherein the polymer (B) is added. 4. The method for producing an impact resistant resin composition according to claim 1, wherein the graft copolymer (B) is added in a semi-molten or molten state. 5. The method for producing an impact resistant resin composition according to claim 1, wherein the rubber-like polymer of the graft copolymer (B) is a diene rubber. 6. A graft copolymer in which the rubber-containing copolymer (A) is a butadiene-styrene-acrylonitrile copolymer, and the graft copolymer (B) is a rubber-like polymer graft-copolymerized with styrene-acrylonitrile. The method for producing an impact-resistant resin composition according to claim 1, which is a united body. 7. A monomer-containing step for continuous bulk polymerization of a rubber-containing copolymer (A) is a vented uniaxial or biaxial extruder, and a graft copolymer (B) continuous addition device is rubber-containing. The method for producing an impact-resistant resin composition according to claim 1, which is a single-screw or twin-screw extruder connected to a demonomer extruder for the copolymer (A).