JPH05331245A - Production of rubber-modified copolymer resin and rubber-modified copolymer resin composition - Google Patents

Abstract

PURPOSE:To obtain the subject resin capable of improving impact resistance and oil resistance of a molded article by subjecting a styrene based monomer to graft copolymerization with (meth)acrylic acid alkyl ester and (meth) acrylonitrile in the presence of a specific copolymer rubber. CONSTITUTION:(B) A styrene-based monomer [preferably styrene] is copolymerized with (C) a (meth)acrylic acid alkyl ester and (D) (meth) acrylonitrile in the presence of (A) a styrene-butadiene copolymer rubber in which the ratio of 1,2-vinyl bond in unsaturated bond based on butadiene is 14-30%, preferably by bulk polymerization to provide the objective resin. Furthermore, the component A is obtained e.g. by subjecting styrene monomer to solution polymerization with butadiene monomer in a nonpolar solvent such as hexane in the presence of a metallic catalyst such as n-butyl lithium and THF.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improved process for producing a rubber-modified copolymer resin and a rubber-modified copolymer resin composition containing the same, and more specifically in the presence of a specific styrene-butadiene copolymer rubber. Styrene monomer and (meth)
TECHNICAL FIELD The present invention relates to a method for producing a rubber-modified copolymer resin which is obtained by graft-copolymerizing an alkyl acrylate and (meth) acrylonitrile and is excellent in oil resistance and drop weight impact strength, and a rubber-modified copolymer resin composition containing the same .

[0002]

2. Description of the Related Art Conventionally, ABS resin has been known as a resin having excellent impact resistance and oil resistance.
Transparent ABS as a product of this ABS resin with transparency
S resin has been industrialized.

As such a transparent ABS resin, for example, JP-B-46-40688 and JP-A-57-30 are known.
Japanese Patent Publication No. 714 describes a method for producing a resin in which styrene, methyl methacrylate and acrylonitrile are graft-polymerized on a styrene-butadiene copolymer rubber.

[0004]

However, none of the copolymer resins obtained by the production method described in the above-mentioned prior art has sufficient impact resistance.

Further, in all of the copolymer resins obtained by the production methods described in the prior art, the bound styrene content of the styrene-butadiene copolymer rubber is less than 25%, and therefore sufficient transparency cannot be obtained, and However, in order to maintain a certain degree of transparency, a large amount of methyl methacrylate must be used, and as a result, there is also a problem that oil resistance is reduced. Further, the transparency obtained by using a large amount of methyl methacrylate is still unsatisfactory.

Further, in JP-A-57-30714, a transparent ABS resin is polymerized by solution polymerization, and the transparency of the resin molded product obtained according to this is not only sufficient, but also industrially. However, since a large amount of solvent is used, there is a problem that the post-treatment process of the polymer is complicated and the cost is increased and the productivity is reduced.

The problem to be solved by the present invention is to provide a rubber-modified copolymer resin which remarkably improves the impact resistance of a molded article and improves the oil resistance, and also to provide styrene-
By providing the styrene content in the butadiene copolymer rubber in a specific range, it is possible to provide a rubber-modified copolymer resin that further significantly improves transparency and oil resistance, and further improve productivity by performing continuous bulk polymerization. It is to provide a method for producing a rubber-modified copolymer resin, which is significantly improved.

[0008]

Means for Solving the Problems As a result of intensive studies conducted by the present inventors in view of such a situation, the ratio of 1,2-vinyl bonds among the unsaturated bonds based on butadiene as a rubbery polymer is 14 to 14%. Graft copolymerization of styrene monomer, (meth) acrylic acid alkyl ester and (meth) acrylonitrile in the presence of 30% styrene-butadiene copolymer rubber results in rubber-modified copolymer which significantly improves impact resistance. That a resin can be obtained, and further that a rubber-modified copolymer resin that significantly improves transparency and oil resistance can be obtained by setting the content of styrene in the styrene-butadiene copolymer rubber within a specific range, and this copolymer resin Has a good balance between the degree of grafting and the degree of crosslinking of the copolymer rubber in the resin, that is, it depends on the toluene insoluble content and toluene. It was found that when the swelling index and the ratio thereof are within a specific range, excellent performance is exhibited,
The present invention has been completed.

That is, according to the present invention, the ratio of 1,2-vinyl bonds among unsaturated bonds based on butadiene is 14 to 30.
% Styrene-butadiene copolymer rubber (A) in the presence of styrene monomer (B), (meth) acrylic acid alkyl ester (C) and (meth) acrylonitrile (D) are graft-copolymerized. And a rubber-modified copolymer resin obtained by graft-copolymerizing a styrene-based monomer, a (meth) acrylic acid alkyl ester and (meth) acrylonitrile in the presence of a styrene-butadiene copolymer rubber And a toluene insoluble content at 25 ° C of 4 to 22% by weight, a swelling index with toluene at 25 ° C of 11 to 19, and a toluene insoluble content / swelling index. Is 0.20 to 1.20% by weight, and relates to a rubber-modified copolymer resin composition.

The styrene-butadiene copolymer rubber (A) used in the present invention has a 1,2-vinyl bond ratio of 1 out of unsaturated bonds based on butadiene which is an essential component.
4 to 30%, preferably 16 to 25%, and the rest are cis and trans bonds. The
When a styrene-butadiene copolymer rubber having a 1,2-vinyl bond ratio of less than 14% is used, the content of toluene insolubles in the rubber-modified copolymer resin is reduced, resulting in excellent transparency and impact resistance. However, if the amount exceeds 30%, the crosslinking at a high temperature during the production progresses and the balance between the grafting ratio and the degree of crosslinking is lost, and the rubber elasticity decreases. However, it is not possible to obtain a product with excellent impact strength.

The styrene-butadiene copolymer rubber (A) is not particularly limited as long as it satisfies the above-mentioned conditions, but is obtained, for example, as follows. That is, the styrene monomer and the butadiene monomer are n-typed in a non-polar solvent such as hexane and cyclohexane.
It can be produced by solution polymerization in the presence of a metal catalyst such as butyl lithium and tetrahydrofuran. At this time, as the amount of tetrahydrofuran used increases, the ratio of 1,2-vinyl bonds among the unsaturated bonds based on butadiene increases. Therefore, by adjusting the amount used, the styrene-butadiene copolymer rubber used in the present invention can be obtained. Is obtained.

Further, the copolymer rubber (A) used in the present invention
As described above, the ratio of 1,2-vinyl bonds among the unsaturated bonds based on butadiene is 14 to 30%, and it is preferable to use a styrene content of bonded styrene of 30 to 55%. It is preferable because it can remarkably improve the transparency and the oil resistance. Above all, the styrene content is 3
It is more preferable that the content is 0 to 45% from the viewpoint that this effect becomes remarkable.

Copolymer rubber (A) thus obtained
Is a 1,4-cis bond and / or a 1,4-vinyl bond other than the 1,2-vinyl bond among the unsaturated bonds based on butadiene.
Although they are trans bonds, the proportion of unsaturated bonds based on butadiene is such that 1,4-cis bonds are 2 respectively.
0-40%, while 1,4-trans coupling is 35-65%
It is preferable that it is excellent in impact resistance improving effect.

Examples of the bonding mode of styrene and butadiene of the above-mentioned copolymer rubber (A) include a random bond and a block bond, and both can be used, but among them, the block bond is preferable.

As the above-mentioned copolymer rubber (A), one having a 5 wt% styrene solution viscosity of 5 to 40 centipoise has a great effect of improving impact strength, and the rubber particle size can be easily controlled during production. Preferably 25 in particular
It is preferable that the viscosity of the 5 wt% styrene solution at 9 ° C. is 9 to 30 centipoise and the Mooney viscosity at 100 ° C. by using the L rotor is 20 to 80.

Styrene-based monomer (B) used in the present invention
Are, for example, styrene, α-methylstyrene, o-
Methyl styrene, m-methyl styrene, p-methyl styrene, ethyl styrene, isobutyl styrene, tertiary butyl styrene, o-bromostyrene, m-bromostyrene, p-bromostyrene, o-chlorostyrene,
Examples thereof include m-chlorostyrene and p-chlorostyrene, and among them, styrene is preferable from the viewpoint of excellent transparency.

The (meth) acrylic acid alkyl ester (C) used in the present invention is an essential component that remarkably improves the transparency of the rubber-modified copolymer resin of the present invention, and includes, for example, methyl (meth) acrylate and (meth ) Ethyl acrylate,
Examples thereof include n-butyl (meth) acrylate, and among them, methyl (meth) acrylate is particularly preferable from the viewpoint of further improving the effect.

The (meth) acrylonitrile (D) used in the present invention is specifically acrylonitrile,
Examples include methacrylonitrile.

The above copolymer rubber (A), styrene monomer (B) and (meth) acrylic acid alkyl ester (C)
The proportion of (meth) acrylonitrile (D) used is usually
The weight ratio of (A) / [(B) + (C) + (D)] is 3/97 to 15/85.
And (A) for the sum of (B), (C), and (D)
Is 30 to 70% by weight, (B) is 20 to 60% by weight,
The range in which (C) is 2 to 30% by weight is preferable from the viewpoint that a product excellent in transparency, strength and oil resistance can be obtained.

The method for producing the rubber-modified copolymer resin of the present invention is as follows. In the presence of the above-mentioned copolymer rubber (A), a styrene monomer (B), a (meth) acrylic acid alkyl ester (C), and a (meth) acrylonitrile (D). ) Is used as an essential component, and may be graft-copolymerized by bulk-suspension polymerization, solution polymerization or bulk polymerization together with other copolymerizable monomers, if necessary. It is preferable from the aspect.

In particular, in a continuous bulk polymerization line incorporating a stirred reactor and a tubular reactor in which a plurality of mixing elements having no moving parts are fixed, a continuous bulk polymerization line is carried out while performing static mixing by the tubular reactor. The bulk polymerization is preferable because the rubber particle diameter is small, the polymer composition can be uniformly controlled, and a rubber-modified copolymer resin excellent in transparency and impact resistance can be efficiently produced.

Other copolymerizable monomers used herein include, for example, vinyl-cyan compounds such as (meth) acrylonitrile; polymerizable unsaturated fatty acids such as itaconic acid, maleic acid, fumaric acid, crotonic acid and cinnamic acid. ;-
Methylmaleimide, N-ethylmaleimide, N-butylmaleimide, N-octylmaleimide, N-isopropylmaleimide, N-phenylmaleimide, Np-bromophenylmaleimide, N-o-chlorophenylmaleimide, N-cyclohexylmaleimide, etc. Maleimides; unsaturated carboxylic acid anhydrides represented by maleic anhydride, itaconic anhydride, citraconic anhydride and the like; allylamine, aminoethyl (meth) acrylate, amino groups such as (meth) acrylic acid-aminopropyl Unsaturated compounds; acrylamide compounds such as acrylamide and N-methyl acrylamide.

A continuous bulk polymerization in which a stirring reactor and a tubular reactor having a plurality of mixing elements without moving parts fixed therein (hereinafter abbreviated as a tubular reactor having a static mixing element) are incorporated. An example of a method for producing a rubber-modified copolymer resin using a line will be described with reference to the drawings.

FIG. 1 is a process diagram showing an example of a continuous bulk polymerization line incorporating a tubular reactor having a static mixing element. The (A) supplied by the plunger pump (1) in the supply line (I),
The mixed solution containing (B), (C) and (D) as essential components is first sent to a prepolymerization line (II) having a stirring reactor (2), and after initial graft polymerization under stirring,
The gear pump (3) sends it to a polymerization line (III) having tubular reactors (4), (5) and (6) having static mixing elements and a gear pump (7) to carry out initial polymerization. The outlet of the initial polymerization line (III) is divided into two parts, and most of the polymerization liquid subjected to the initial polymerization is returned to the initial polymerization line (III) through the reflux line (V), and the initial polymerization line (III) and reflux. It is circulated in a circle formed by the line (V) (hereinafter referred to as a circulation polymerization line). The remaining polymerization liquid is introduced into a main polymerization line (IV) in which tubular reactors (7), (8) and (9) having static mixing elements are installed in series and main polymerization is carried out there.

By combining the pre-graft polymerization in the pre-polymerization line (I), that is, in the stirring reactor (2) with the circulation polymerization line, the rubber particles are prevented from being excessively sheared. More efficient miniaturization of
At the same time, it is preferable in that the polymer composition in the polymerization step can be made uniform. In the pre-graft polymerization in this case, the total polymerization conversion rate of the styrene-based monomer (B) and the (meth) acrylic acid alkyl ester (C) and the (meth) acrylonitrile (D) is determined at the outlet of the reactor (2). 10-30
It is carried out so that the amount is preferably 14 to 26% by weight.

The stirring reactor (2) may be, for example, a stirring tank reactor or a stirring tower reactor, and the stirring blade may be, for example, an anchor type, a turbine type, a screw type or a double helical type. Examples include a stirring blade such as a mold.

In the present invention, a solvent may be used in order to reduce the viscosity of the mixed solution in the reactor, and the amount thereof is 5 to 20 parts by weight based on 100 parts by weight of the raw material monomers in total. . As the type of solvent, toluene, ethylbenzene, xylene and the like which are usually used in the bulk polymerization method are suitable.

In the present invention, it is preferable to add a chain transfer agent to the mixed solution in order to control the molecular weight of the rubber-modified copolymer resin. The amount of the chain transfer agent added is usually 0.05 to 0.5 with respect to 100 parts by weight of the total amount of the raw material monomers.
It is a range of parts.

The rubber particles in the mixed solution in the circulation polymerization line are statically mixed and stabilized while circulating in the circulation polymerization line, and the particle diameter is also fixed. In this case, the reflux ratio (R) and (B) of the mixed solution in the circulation polymerization line,
The total polymerization conversion rate of (C) and (D) is an important factor.

The reflux ratio R is the flow rate of the mixed solution which is refluxed in the circulation polymerization line without flowing into the main polymerization line (V) and is F1.
When the flow rate of the mixed solution flowing from the circulation polymerization line (I) to the main polymerization line (V) is F2 (liters / hour), the reflux ratio is usually R = F1 /
F2 is in the range of 3 to 15, in particular, the pressure loss in the tubular reactor is small, the produced rubbery polymer particles are stable, the particle size can be made small, and the rubber-modified copolymer resin contains The range of R = 5 to 10 is particularly preferable in that the content ratio of (B), (C) and (D) can be kept constant.

In the graft polymerization in the circulating polymerization line, the total polymerization conversion rate of (B), (C) and (D) at the outlet of the circulating polymerization line is usually 35 to 55% by weight,
Polymerization is preferably performed so as to be 40 to 50% by weight. A suitable polymerization temperature is 120 to 135 ° C.

The mixed solution graft-polymerized in the circulation polymerization line is then fed to the main ring polymerization line (V), and the total of (B), (C) and (D) is usually added at a polymerization temperature of 140 to 160 ° C. Graft polymerization is continuously carried out until the conversion becomes 60 to 80% by weight. Next, this mixed solution is sent to a preheater and then to a devolatilization tank by a Kia pump (11) to remove unreacted monomers and solvent under reduced pressure,
The target rubber-modified copolymer resin can be obtained by pelletizing. At this time, it is preferable to perform the preheating and the devolatilization under the condition that the increase of the conversion rate in the preheater and the devolatilization tank is 10% by weight or less.

As the plurality of mixing elements fixed in the tubular reactor having the static mixing element used in the present invention, for example, the flow of the polymerization liquid flowing into the tubes is divided and the flow direction is changed, and the division and the joining are performed. A method in which the polymerization liquid is mixed by repeating the above is mentioned. Such tubular reactors include, for example, SMX type, SMR
Type Sulzer type tubular mixer, Kenix type static mixer, Toray type tubular mixer and the like are preferable.
A tubular reactor having such a static mixing element is shown in FIG. 2 as an example.

The number of these tubular reactors incorporated in the initial polymerization line (III) and the main polymerization line (V) is particularly limited because, in the case of the tubular reactor as described above, it varies depending on its length and the structure of the mixing element. However, the tubular reactor with four or more mixing elements is not
-15, preferably 6-10 are used in combination. Among these, the number of the tubular reactors incorporated in the circulation polymerization line (I) is usually 1 to 10, preferably 2 to 6.

The mixed solution used as a raw material in the present invention includes
It is preferable to add an organic peroxide that releases a free radical when decomposed as a polymerization initiator, if necessary, because grafting and reaction can be promoted at a relatively low temperature. The amount added is in the range of 0.005 to 0.04 parts by weight with respect to 100 parts by weight of the total of the raw material monomers.

The organic peroxide used here preferably has a half-life of 10 hours at a temperature of 75 to 170 ° C., and specific examples thereof include 1,1-di-t-butylperoxycyclohexane and 1-di-t-butylperoxycyclohexane. , 1-di-t-butylperoxy-3,
3,5-Trimethylcyclohexane, 2,2-di-t-butylperoxyoctane, n-butyl-4,4-di-t-butylperoxyvalerate, 2,2-di-t-butylperoxybutane Peroxyketals such as t-butylperoxyacetate, t-butylperoxy-3,5,5-trimethylhexanoate, t-butylperoxylaurate, t
-Butylperoxybenzoate, di-t-butyldiperoxyisophthalate, 2,5-dimethyl-2,5-dibenzoylperoxyhexane, t-butylperoxymaleic acid, t-butylperoxyisopropyl carbonate, di- Examples thereof include peroxyesters such as -t-butyl peroxide, dicumyl peroxide, t-butyl hydroperoxide and cumene hydroperoxide, which may be used alone or in combination of two or more.

Further, if necessary, the mixed solution used in the present invention contains a plasticizer such as mineral oil, an antioxidant,
Known additives such as a chain transfer agent, a long-chain fatty acid, a release agent such as an ester thereof or a metal salt thereof, and a silicone oil may be used in combination.

The rubber-modified copolymer resin composition of the present invention is a rubber obtained by graft-copolymerizing a styrene-based monomer, a (meth) acrylic acid alkyl ester and a (meth) acrylonitrile in the presence of a styrene-butadiene copolymer rubber. The modified copolymer resin and the plasticizer are essential components, the content of toluene insoluble matter at 25 ° C. is 4 to 22% by weight, the swelling index by toluene is 11 to 19, and the content of toluene insoluble matter / swelling index is Is 0.20 to 1.20% by weight, but when the rubber-modified copolymer resin composition satisfies this range, a molded article excellent in impact resistance, transparency and oil resistance can be obtained.

As a method for graft-copolymerizing a styrene-based monomer, a (meth) acrylic acid alkyl ester, and a (meth) acrylonitrile in the presence of a styrene-butadiene copolymer rubber, the above-mentioned rubber-modified copolymer resin of the present invention can be used. The production method of is preferably used. That is, the rubber-modified copolymer resin obtained according to the production method of the present invention is preferably obtained by adding a plasticizer during the polymerization step to obtain a rubber-modified copolymer resin composition, each of which has a temperature of 25 ° C. The content of toluene-insoluble matter is 4 to 22% by weight, the swelling index with toluene is 11 to 19 and the content of toluene-insoluble matter / swelling index is 0.20 to 1.20% by weight. is there.

The average rubber particle diameter of the styrene-butadiene copolymer rubber in the composition is preferably 0.05 to 0.80 μm, and in particular, it is 0 from the viewpoint of excellent transparency and impact resistance of the molded product. It is preferably from 10 to 0.60 μm.

Further, as the rubber-modified copolymer resin,
A styrene monomer that is the matrix phase in the resin,
The weight average molecular weight (Mw) of the copolymer of (meth) acrylic acid alkyl ester and (meth) acrylonitrile is 100,000 to 160,000, and the ratio Mw / of the weight average molecular weight (Mw) and the number average molecular weight (Mn). Mn of 1.8 to 2.5 is preferable, and in particular, the weight average molecular weight (Mw) is 12
Particularly preferred are those of 150,000 to 150,000.

The plasticizer is an essential component of the composition of the present invention which remarkably improves the fluidity of the rubber-modified copolymer resin upon melting without lowering the transparency of the molded product. The plasticizer is not particularly limited, but ester-based plasticizers and polyester-based plasticizers are preferable, and among them, dibutyl phthalate and butyl benzyl phthalate are preferable in that the above effects become remarkable.

The composition of the present invention may further contain commonly used antioxidants, ultraviolet absorbers, lubricants, flame retardants, antistatic agents, foaming agents, reinforcing materials and the like.

Of these, preferred are, for example, mineral oil, organic polysiloxane, higher fatty acids and their metal salts, hindered phenolic antioxidants,
Glass fibers and the like can be used, and each can be used alone or in combination.

Further, the rubber-modified copolymer resin of the present invention is further subjected to injection molding, uniaxial extrusion molding, biaxial stretch extrusion molding, inflation extrusion molding, profile extrusion molding, vacuum molding, pressure molding, blow molding and the like. Various molded products can be used by the molding method of. It has a wide range of uses, for example, components for household electric appliances and appliances such as radio cassettes, audio players, video tape recorders; OA for copiers, printers, facsimiles, personal computers, etc.
Various parts of equipment; IC carrier-magazine; food container;
Parts for medical instruments; used as blister packages, food packaging containers, etc. Further, the rubber-modified copolymer resin of the present invention includes polystyrene resin, rubber-modified polystyrene resin, AS resin, ABS resin, styrene-methyl methacrylate copolymer resin, rubber-modified styrene-methyl methacrylate copolymer resin, if necessary. A thermoplastic resin such as a (meth) acrylic resin, a styrene-maleic anhydride copolymer resin, a styrene- (meth) acrylic acid copolymer resin, a polycarbonate resin, or a vinyl chloride resin may be appropriately added.

The methods for measuring the average particle diameter of the rubbery polymer, the toluene insoluble content and the swelling index with toluene are described below. 1. Average particle size of rubbery polymer in resin Take transmission electron micrograph of resin by ultra-thin section method,
The particle diameter of 1000 particles in the photograph was measured, and the average particle diameter was determined by the following formula. (However, ni is the number of rubber particles having the particle size Di.) Toluene insoluble content and swelling index with toluene 1 g of rubber-modified copolymer resin is precisely weighed and 100 ml of toluene is added.
Dissolve the solution in a centrifuge tube at 25 ° C for 24 hours, centrifuge at 10 ° C or less and 12000 rpm for 15 minutes, remove the supernatant by decantation, and swell with insoluble toluene. Weigh the minutes. Next, it is dried in a vacuum dryer at 60 ° C. for 24 hours, the weight of the obtained toluene insoluble matter is measured, and the toluene insoluble matter content rate is calculated by the following formula. The swelling index is calculated by the following formula. 3. Method for Measuring Ratio of 1,2-Vinyl Bond in Copolymer Rubber It was measured by infrared spectroscopic analysis (Morero method).

[0047]

EXAMPLES The present invention will be described more specifically by showing Examples and Comparative Examples below. However, all parts in the examples are parts by weight, and% is% by weight except for the total light transmittance and the ratio of 1,2-vinyl bonds.

The physical properties in the examples were measured as follows. 1) Drop weight impact strength Injection molding machine with a cylinder temperature of 240 ° C (Japan Steel Works J150
Box-shaped molded product (180 mm x 1) injection-molded using SSIIA)
26 mm x 25 mm, wall thickness 2 mm) with the bottom part facing up, and a steel ball with a weight of 1 kg is dropped in the center, and the drop weight impact strength is determined by the product of the drop height and the weight of the steel ball until it breaks. I asked for it. 2) Izod impact value, flexural strength and flexural modulus based on JIS K-6871. 3) Total light transmittance and haze value A test piece having a thickness of 2 mm was made by an injection molding method, and its value was determined according to ASTM D-1003. 4) Oil resistance test of molded product A dumbbell test piece having a length of 165 mm is fixed in a bow shape to a test jig having a length of 160 mm to give strain. Oil was applied to the surface of the test piece and left at 23 ° C. and 50% humidity. The appearance of the molded product after a certain period of time was observed. Salad oil (edible soybean oil) was used in this test.

Example 1 In this example, an apparatus arranged as shown in FIG. 1 was used. A mixed solution containing styrene, methyl methacrylate, acrylonitrile, a rubbery polymer and a solvent was sent by a plunger pump (1) to a 20 liter stirred reactor (2), and initial grafting was performed under dynamic mixing by a stirring blade. Polymerized. Then, this mixed solution is sent to the initial polymerization line (I) by the gear pump (3). The initial polymerization line (I) is a tubular reactor with an inner diameter of 2.5 inches in order from the inlet (built-in SMX type static mixer manufactured by Gebrüder-Sulzer, Switzerland, with 30 static mixing elements).
(4), (5) and (6) and a gear pump (7) for circulating the mixed solution. An outlet leading to the main polymerization line (V) is provided between the tubular reactor (6) and the reflux line (V) having a gear pump (7). To the main polymerization line (V), tubular reactors (8), (9) and (10) similar to the above and a gear pump (11) are connected in series from the inlet in order.

Styrene-butadiene block copolymer rubber [5% styrene solution viscosity at 25 ° C. (hereinafter 5% SV
Abbreviated): 20 centipoise, ratio of 1,2-vinyl bonds:
17%, styrene / butadiene weight ratio: 35/65] 7 parts,
A mixed solution containing 45 parts of styrene, 45 parts of methyl methacrylate, 10 parts of acrylonitrile and 10 parts of ethylbenzene was prepared, and the monomer mixture 1 was used as a plasticizer.
0 part to 2 parts dibutyl phthalate, 0.1 part to 100 parts of the monomer mixture as chain transfer agent and 0.1 part to 100 parts of the monomer mixture as organic peroxide and 0.1 part of n-dodecyl mercaptan. 02 parts of t-butylperoxybenzoate was added and continuous bulk polymerization was carried out using the above apparatus under the following conditions.

Continuous supply of mixed solution: 10 liters / hour Reflux ratio R: 7 Reaction temperature in stirred reactor (2): 120 ° C Reaction temperature in initial polymerization line (III): 135 ° C Main polymerization Reaction temperature in line (IV): 140 to 160 ° C. The mixed solution obtained by polymerization is heated to 225 ° C. in a heat exchanger, and volatile components are removed under reduced pressure of 50 mmHg, and then pelletized to produce the present invention. A rubber-modified copolymer resin composition of was obtained.

Table 1 shows the analytical data and the measurement results of the physical properties of the resin.

Example 2 Styrene-butadiene block copolymer rubber [5% SV:
10 centipoise, 1,2-vinyl bond ratio: 19%, styrene / butadiene weight ratio: 41/59] 8 parts, styrene 5
0 parts, methyl methacrylate 35 parts, acrylonitrile 1
A rubber-modified copolymer resin composition of the present invention was obtained in the same manner as in Example 1 except that a mixed solution containing 5 parts and 10 parts of ethylbenzene was used. Table 1 shows analytical data and measurement results of physical properties.

Example 3 Complete mixing type 20 liter tank type reactors (i), (ii) and (iii) equipped with a helical stirring blade, a heat exchanger and a devolatilizing tank were connected in series. The polymerization reaction was carried out using a continuous reaction apparatus arranged in this manner. A mixed solution of 7 parts of styrene-butadiene block copolymer rubber similar to that used in Example 1, 45 parts of styrene, 45 parts of methyl methacrylate, 10 parts of acrylonitrile and 10 parts of ethylbenzene was prepared, and further as a plasticizer. Monomer mixture 100
2 parts butylbenzyl phthalate to 0.1 part, 0.1 part n-per 100 parts of the monomer mixture as a chain transfer agent.
Dodecyl mercaptan and 0.02 part of t-butylperoxybenzoate were added to 100 parts of the monomer mixture as the organic peroxide, and bulk polymerization was continuously carried out using the above apparatus under the following conditions.

Continuous supply of mixed solution: 7 liters /
Time Reaction temperature in tank reactor (i): 125 ° C. Reaction temperature in tank reactor (ii): 130 ° C. Reaction temperature in tank reactor (iii): 145 ° C. or less, same as in Example 1 Thus, a rubber-modified copolymer resin composition of the present invention was obtained. Table 1 shows analytical data and measurement results of physical properties.

Comparative Example 1 Styrene-butadiene copolymer rubber "Tuffden AS" (5
% SV is 50 cps, 1,2-vinyl bond ratio is 13
%, The styrene / butadiene weight ratio is 25/75) 6
Parts, styrene 32 parts, methyl methacrylate 52 parts, acrylonitrile 10 parts, and ethylbenzene 10 parts to prepare a rubber-modified copolymer resin composition in the same manner as in Example 3 except that a mixed solution was prepared. Table 1 shows analytical data and measurement results of physical properties.

[0057]

[Table 1]

[0058]

EFFECTS OF THE INVENTION According to the present invention, a rubber-modified copolymer resin having a molded article with extremely excellent impact resistance and oil resistance can be provided, and the content of bound styrene in the copolymer rubber (A) is further improved. When the ratio is within the specific range, it is possible to provide a rubber-modified copolymer resin that significantly improves the oil resistance and transparency of the molded product. Further, when continuous bulk polymerization is performed, the productivity is remarkably improved. The rubber-modified copolymer resin obtained by the production method of the present invention is excellent in transparency, oil resistance and practical strength such as falling weight impact strength, and thus can be suitably used for various molded products.

[Brief description of drawings]

FIG. 1 is a process diagram showing an example of a continuous polymerization line incorporating a tubular reactor having a static mixing element therein. (1): Plunger pump (2): Stirring type reactor (3): Gear pump (4): Static mixing element (5): Tubular reactor having a static mixing element inside (6): Static mixing Tubular reactor with internal elements (7): Gear pump (8): Tubular reactor with static mixing elements inside (9): Tubular reactor with static mixing elements inside (10): Static mixing Tubular reactor having elements inside (11): Gear pump (I): Raw material supply line (II): Preliminary polymerization line (III): Initial polymerization line (IV): Main polymerization line (V): Reflux line

FIG. 2 is a cross-sectional perspective view of an example of a tubular reactor having a static mixing element inside. a: Static mixing element b: Tubular reactor

Claims (12)

[Claims] 1. Of butadiene-based unsaturated bonds,
Styrene having a 1,2-vinyl bond ratio of 14 to 30%
Rubber modification characterized by graft-copolymerizing a styrene monomer (B), a (meth) acrylic acid alkyl ester (C) and a (meth) acrylonitrile (D) in the presence of a butadiene copolymer rubber (A) Manufacturing method of copolymer resin. 2. A styrene-butadiene copolymer rubber (A)
Is a copolymer rubber having a styrene content of 30 to 55%. 3. A styrene-butadiene copolymer rubber (A)
Is a copolymer rubber having a styrene content of 30 to 45%. 4. A styrene-butadiene copolymer rubber (A)
Is a copolymer rubber having a 5 wt% styrene solution viscosity at 25 ° C. of 5 to 40 centipoise, and the process according to claim 1, 2 or 3. 5. The styrene monomer (B) is styrene, and a (meth) acrylic acid alkyl ester (C) is used.
Is methyl (meth) acrylate and (meth) acrylonitrile (D) is acrylonitrile.
The method according to 2, 3, or 4. 6. A styrene-butadiene copolymer rubber (A)
And styrene monomer (B), (meth) acrylic acid alkyl ester (C), and (meth) acrylonitrile (D), the weight ratio of (A) / [(B) + (C) + (D)] is 3/97 to 15/85, and (B) is 30 to 70% by weight with respect to the total of (B), (C) and (D),
The method according to claim 1, 2, 3, 4 or 5, wherein (C) is used in the range of 20 to 60% by weight and (D) is in the range of 2 to 30% by weight. 7. Graft copolymerization in a continuous bulk polymerization line incorporating a stirred reactor followed by a tubular reactor in which a plurality of mixing elements without moving parts are fixed. The manufacturing method according to 3, 4, 5 or 6. 8. A styrene-butadiene copolymer rubber (A), a styrene monomer (B), a (meth) acrylic acid alkyl ester (C) and a (meth) acrylonitrile ( A mixed solution containing D) and a. A raw material supply line (I), b. A pre-polymerization line (I) incorporating a stirring type reactor having a stirring blade inside, continuing from the raw material supply line (I)
I), and c. Continuing from the pre-polymerization line (II), there are a plurality of mixing elements fixed inside that have no moving parts 1
Initial polymerization line consisting of one or more tubular reactors (III)
And d. A main polymerization line (IV) consisting of one or more tubular reactors continuing from the initial polymerization line (III) and having fixed therein a plurality of mixing elements with no moving parts; e. A polymerization line constituted by a reflux line (V) branched between the initial polymerization line (III) and the main polymerization line (IV) and returning to the initial polymerization line (III) is used, and the initial polymerization line (III) is used. 8. The process according to claim 7, wherein a part or most of the initial polymerization liquid stream that comes out is refluxed through the reflux line (V), while the unpolymerized initial polymerization liquid stream is graft-copolymerized in the main polymerization line (IV). . 9. A rubber-modified copolymer resin obtained by graft-copolymerizing a styrene-based monomer, a (meth) acrylic acid alkyl ester and a (meth) acrylonitrile in the presence of a styrene-butadiene copolymer rubber, and a plasticizer as essential components. And the toluene insoluble content at 25 ° C is 4
~ 22 wt%, swelling index with toluene at 25 ° C is 1
A rubber-modified copolymer resin composition having a content of 1 to 19 and a toluene insoluble content / swelling index of 0.20 to 1.20% by weight. 10. The average particle size of the styrene-butadiene copolymer rubber in the thermoplastic resin is 0.05 to 0.80 μm.
The composition according to claim 9, which is 11. The composition according to claim 9, wherein the plasticizer contains an ester- and polyester-based plasticizer. 12. The composition according to claim 11, wherein the plasticizer is dibutyl phthalate or butyl benzyl phthalate.