JP2000103933A - Styrene-based resin composition and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject composition useful for e.g. sheet molded products with excellent gloss, rigidity and planar impact strength by using specific rubber particles as disperse particles. SOLUTION: This composition comprises (A), as matrix phase a copolymer prepared by copolymerization between (i) a styrene-based monomer and (ii) an acrylic monomer, in particular a (meth)acrylic alkyl ester in the weight ratio (i)/(ii) of (95:5) to (50:50) and (B), as disperse phase, i.e., disperse particles, rubber particles prepared by graft copolymerization of both styrene-based monomer and acrylic monomer to a diene-based rubbery polymer, wherein the rubber particles are such ones as to be each 0.5-0.9 μm in the median diameter on a volume basis in this composition when determined using a scattering-type particle size distribution measuring device and 1.2-2.5 in the value of the ratio: [toluene insolubles content at 25 deg.C/toluene swelling index at 25 deg.C] determined for this composition.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a rubber-modified styrene resin composition in which a grafted rubbery polymer is dispersed in a styrene matrix resin. More specifically, the present invention relates to a styrene-based resin composition having excellent impact resistance, particularly excellent surface impact strength, and excellent gloss and rigidity, and a method for producing the same.

[0002]

2. Description of the Related Art Rubber-modified styrene resins such as HIPS are now widely used as thermoplastic resins having excellent impact resistance. Such a rubber-modified styrene resin represented by HIPS generally has a disadvantage that the dispersed rubber particle diameter is as large as 1 μm or more, and as a result, the gloss of the molded product is inferior. Therefore, the development of a resin having both the gloss and impact resistance of HIPS has been promoted.
No. 1122 discloses a technique in which the graft rubber particles in HIPS are reduced to a particle size of 0.5 to 1.0 μm to achieve both gloss and impact resistance. Japanese Patent Application Laid-Open No. 4-180907 discloses a technique of graft polymerizing styrene and methyl methacrylate to a rubber component as a resin composition having excellent transparency, rigidity and impact resistance.

[0003]

SUMMARY OF THE INVENTION However, Japanese Patent Application Laid-Open No.
In the technology described in Japanese Patent Publication No. 122, although the gloss is improved to some extent by reducing the rubber particle diameter, the impact strength is significantly reduced due to the reduction in the particle diameter, so that the rubber particle diameter is reduced and the impact strength is increased. In order to obtain a product, the rubber content in the product must be increased as compared with general HIPS, and as a result, the rigidity characteristic of the styrene-based resin is reduced. In addition, when a large amount of the rubber component having a small particle diameter is used in this manner, there is also a problem that the notched Izod impact strength is high, but the practically important surface impact strength is low, although the impact strength is high. I was

The resin composition described in Japanese Patent Application Laid-Open No. 4-180907 has good gloss due to transparency, but has a smaller particle size for transparency, resulting in a smaller particle size. In addition, the impact resistance was not sufficient and the application was limited. An object of the present invention is to provide a styrene-based resin composition having excellent gloss, rigidity and surface impact strength.

[0005]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies in view of such a situation, and as a result, a styrene-based monomer and a styrene-based monomer have been added to a mixed rubber polymer in which two specific rubber components are dissolved. Graft copolymerization with alkyl (meth) acrylate to reduce the volume-based median diameter of the dispersed rubber particles and increase the degree of cross-linking, thereby significantly increasing rigidity and practical impact strength while having excellent molded product gloss. And found that the present invention was completed.

That is, according to the present invention, a copolymer (A) of a styrene monomer and an acrylic monomer is used as a matrix phase, and a styrene monomer and an acrylic In a styrene-based resin composition in which rubber particles (B) in which a monomer is graft-copolymerized are dispersed particles, the copolymer (A) is obtained by mixing a styrene-based monomer and an alkyl (meth) acrylate with: The former / the latter is copolymerized at a ratio of 95/5 to 50/50 on a weight basis, and the rubber particles (B) are based on a volume basis in the composition measured by a scattering type particle size distribution analyzer. Median diameter 0.5 ~
It is in the range of 0.9 μm and the composition [toluene insoluble content at 25 ° C./toluene swelling index at 25 ° C.]
Is in the range of 1.2 to 2.5, and a homopolymer (b1) of a diene monomer or a styrene structural unit on a weight basis. A copolymer (b2) of a styrene monomer and a diene monomer having a ratio of 15% or less, and a styrene monomer having a styrene structural unit at a ratio of 20 to 50% by weight And a copolymer (b3) of a diene monomer and
A continuous mass obtained by incorporating a mixed solution of a styrene-based monomer (a1) and an alkyl (meth) acrylate (a2) into a tubular reactor having a plurality of mixing elements having no movable parts fixed therein. The present invention relates to a method for producing a styrene-based resin, which is characterized by performing continuous bulk polymerization in a polymerization line.

In the present invention, the copolymer (A) of a styrene monomer and an acrylic monomer which forms a matrix phase comprises a styrene monomer and an alkyl (meth) acrylate on a weight basis. And the former / the latter = 95/5-
It is copolymerized at a ratio of 50/50. Here, the alkyl (meth) acrylate is 50% by weight.
When the ratio exceeds the above range, the fluidity of the composition is reduced and the transferability of the mold surface is deteriorated, so that the gloss of the molded product is significantly reduced. If the amount is less than 5% by weight, the impact strength and the rigidity of the molded product are reduced.

[0008] Further, as in the resin composition described in JP-A-4-180907, those having a large amount of acrylic component such as 40 to 70% by weight of an alkyl acrylate in a matrix are prepared by melting a molded article again. Reuse after blending into polystyrene or the like, that is, in addition to having a serious disadvantage in practice such that recycling is not possible, it is susceptible to erosion by solvents, for example, when printing on molded products, solvent of ink Has a drawback that it is inferior in chemical resistance, that is, cracks easily occur due to erosion.

Therefore, while maintaining the performance of the present invention such as gloss, impact strength and rigidity of the molded product, it is possible to use the recycled product such as blending the recovered product with polystyrene, and it has good chemical resistance. From this point, the copolymer (A) is obtained by copolymerizing a styrene monomer and an alkyl (meth) acrylate in a ratio of 95/5 to 81/19 on a weight basis. preferable.

The styrene monomer includes, for example, styrene, α-methylstyrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, ethylstyrene, isobutylstyrene, tertiary butylstyrene, o-methylstyrene. Bromostyrene, m-bromostyrene, p
-Bromostyrene, o-chlorostyrene, m-chlorostyrene, p-chlorostyrene and the like, among which styrene is preferred.

The alkyl (meth) acrylate is an essential component for imparting surface impact strength and rigidity to the rubber-modified copolymer resin of the present invention, and specifically, methyl (meth) acrylate, ( Ethyl (meth) acrylate, propyl (meth) acrylate, n-butyl (meth) acrylate, iso-butyl (meth) acrylate, 2- (meth) acrylate
Ethylhexyl and the like are mentioned, and methyl methacrylate is particularly preferred in view of cost and performance such as surface impact strength and rigidity. These alkyl (meth) acrylates may be used alone or in combination of two or more. However, in particular, from the viewpoint of gloss, methyl methacrylate and (meth) acrylic acid- It is preferable to use n-butyl in combination. At this time, the amount of the n-butyl (meth) acrylate used is not particularly limited, but is 1 to 8 parts by weight, especially 2 to 5 parts by weight, based on 100 parts by weight of the raw material monomer. Is preferred.

The copolymer (A) forming the matrix may further include other copolymerizable monomers as long as the effects of the present invention are not impaired, for example, vinyl-cyanide compounds such as (meth) acrylonitrile. And the like; polymerizable unsaturated fatty acids such as (meth) acrylic acid, itaconic acid, maleic acid, fumaric acid, crotonic acid, and cinnamic acid; N-methylmaleimide, N-ethylmaleimide, N-butylmaleimide;
N-octylmaleimide, N-isopropylmaleimide, N-phenylmaleimide, Np-bromophenylmaleimide, No-chlorophenylmaleimide, N-
Maleimides such as cyclohexylmaleimide; unsaturated carboxylic anhydrides such as maleic anhydride, itaconic anhydride and citraconic anhydride; allylamine, aminoethyl (meth) acrylate, aminopropyl (meth) acrylate and the like And acrylamide-based compounds such as acrylamide and N-methylacrylamide. The use ratio of the other copolymerizable monomer is not particularly limited, but is preferably a ratio of not more than 5% by weight in all the monomer components forming the copolymer (A). .

Next, the rubber particles (B) dispersed in the matrix are graft copolymers obtained by graft copolymerization of a styrene monomer and an acrylic monomer on a diene rubber polymer, The volume-based median diameter in the composition measured by a scattering particle size distribution analyzer is 0.5 to 0.9 μm
And the value of [toluene insoluble content at 25 ° C./toluene swelling index at 25 ° C.] is 1.2 to 2.5 in the entire composition. It is characterized by.

That is, the volume-based median diameter of the rubber particles (B) measured by a scattering type particle size distribution analyzer is 0.5 to 0.5%.
When the thickness is in the range of 0.9 μm, the gloss of the molded product is extremely excellent. In general, when the dispersed particle diameter is reduced as described above, the content of the crosslinked product in the graft polymer is reduced, and the content of [toluene insoluble content at 25 ° C / toluene swelling index at 25 ° C] in the composition is reduced. Although the value is less than 1.0, in the present invention, when the value is in the range of 1.2 to 2.5, the rigidity and impact strength of the molded product, particularly the surface impact strength, are remarkably improved.

Here, the “toluene insoluble content at 25 ° C.” means that 1 g of a sample is precisely weighed, and 2 g is added to 100 ml of toluene.
After dissolving at 5 ° C. for 24 hours, the swollen insoluble matter was taken out and dried, and the value of the weight of the obtained dry resin was expressed as a percentage with respect to the sample.
Preferably it is 20% by weight.

The "toluene swelling index at 25.degree. C." means that 1 g of a sample is precisely weighed, dissolved in 100 ml of toluene at 25.degree. C. for 24 hours, and the swollen insoluble matter is taken out. It is a value obtained by measuring the weight and then drying the insoluble matter, and dividing the weight of the insoluble matter by the weight of the dry resin.

In the present invention, as described above, the value of [toluene insoluble content at 25 ° C./toluene swelling index at 25 ° C.] in the composition is in the range of 1.2 to 2.5. , 1.2, the rigidity and impact strength are low, and if it exceeds 2.5, the rigidity is good but the surface impact strength is inferior. In the present invention, the surface impact strength and the Izod impact strength are preferably in the range of 1.2 to 2.0 from the viewpoint of further improving the impact strength.

The rubber particles (B), which are dispersed particles, are obtained by graft copolymerization of a styrene-based monomer and an acryl-based monomer with a diene-based rubbery polymer. The union is not particularly limited, but is a homopolymer of a diene monomer such as polybutadiene, low cis polybutadiene, and high cis polybutadiene, or a styrene monomer and a diene monomer. As described in detail below, in the present invention, a homopolymer (b1) of a diene monomer or styrene having a styrene structural unit in a proportion of 15% or less by weight is used in the present invention. (B2) of a styrene-based monomer and a diene-based monomer, and 20 to 50 parts by weight of a styrene structural unit.
% Of the copolymer (b3) of a styrene-based monomer and a diene-based monomer having a ratio of 2% and preferably subjected to graft copolymerization.

The rubbery polymer (b1) used in the present invention comprises:
As described above, it is a homopolymer of a diene monomer, for example, polybutadiene, such as low-cis polybutadiene and high-cis polybutadiene. The copolymer (b2) of the styrene-based monomer and the diene-based monomer having the styrene structural unit at a ratio of 15% or less on a weight basis may be a block bond or a random bond. Here, examples of the styrene monomer constituting the copolymer rubber of the styrene monomer and the diene monomer include styrene, α-methylstyrene, o-methylstyrene, m-methylstyrene, and p-methylstyrene. Methyl styrene, ethyl styrene,
Isobutyl styrene, tertiary butyl styrene, o
-Bromostyrene, m-bromostyrene, p-bromostyrene, o-chlorostyrene, m-chlorostyrene, p
-Chlorostyrene and the like, among which styrene is preferred because of its excellent reactivity with diene monomers.

On the other hand, as the diene monomer to be reacted with the styrene monomer, butadiene, chloroprene,
Isoprene, 1,3-pentadiene, and the like,
Among them, butadiene is preferred because of its excellent reactivity with the styrene monomer.

Therefore, as the copolymer (b2), a styrene-butadiene copolymer rubber containing a styrene structural unit in a range of not more than 15% by weight is preferable.

The above polymer (b1) or copolymer (b2)
Represents 1,2 of the unsaturated bonds based on the diene monomer.
-When the ratio of vinyl bonds is 8 to 35% by weight, the content of toluene-insoluble components in the rubber-modified copolymer resin increases, and furthermore, the progress of crosslinking at high temperature during production can be suppressed, and the grafting ratio can be reduced. This is preferable because the balance between the degree of crosslinking and the degree of crosslinking is improved and rubber elasticity is improved.

The polymer (b1) or the copolymer (b)
2) is preferably a 5% by weight styrene solution having a viscosity of 30 to 50 centipoise in that the impact resistance is greatly improved and the rubber particle diameter can be easily controlled during the production. In particular, 5% by weight at 25 ° C. Styrene solution viscosity 30 ~
Those having 45 centipoise and a Mooney viscosity of 20 to 80 using an L rotor at 100 ° C. are preferred.

Next, the copolymer (b3) used together with the polymer (b1) or the copolymer (b2) is a styrene-based monomer having a styrene structural unit in a proportion of 20 to 50% by weight. It is a copolymer of a monomer and a diene monomer.
The bonding mode of the copolymer is preferably block bonding or tapered block bonding.

In the copolymer (b3), those having a 1,2-vinyl bond ratio of 8 to 35% by weight among unsaturated bonds based on diene monomers are used in the rubber-modified copolymer resin. The content of toluene insolubles increases, and furthermore, the progress of crosslinking at high temperature during production can be suppressed, and the balance between the grafting rate and the degree of crosslinking is improved, improving rubber elasticity and impact resistance. Is preferable in that the value is significantly improved. in this case,
The remainder of the 1,2-vinyl bond forms cis and trans bonds.

Further, the copolymer (b3) used in the present invention
A 5% by weight styrene solution having a 5% by weight styrene solution viscosity of 5 to 50 centipoise is preferred in that the impact resistance is greatly improved and the rubber particle diameter can be easily controlled during production. Preferred are those having a viscosity of 8 to 40 centipoise and a Mooney viscosity of 20 to 80 using an L rotor at 100 ° C.

The rubbery polymer (b1) or copolymer (b2) and copolymer (b3) described in detail above are composed of a styrene monomer (a1) and an alkyl (meth) acrylate (a2). And then graft copolymerized to form rubber particles (B).

The shape of the rubber particles (B) existing in the matrix is not particularly limited, but the internal structure of the rubber particles may take a so-called "salami structure" to obtain impact strength, particularly surface area. It is preferable from the viewpoint of impact strength.

More specifically, the dispersion state of the rubber particles (B) in the composition includes a rubber particle (B1) having a salami structure and a rubber particle (B2) having a core-shell structure.
Are coexistent, and a transmission electron micrograph (100
When the number of particles was 1000, the abundance ratio between the rubber particles (B1) and the rubber particles (B2) was (B1) /
(B2) = 70/30 to 95/5 is preferable because the balance between gloss and surface impact strength is good.
That is, in the present invention, despite the small particle size,
Since most of the rubber particles have a salami structure, it is possible to obtain a molded article having a low gloss and excellent surface impact strength. Also,
Since the other rubber particles (B) having the salami structure are the rubber particles (B2) having the core-shell structure, the gloss of the molded product is more excellent.

As described above, the rubber particles (B) in the composition have a volume-based median diameter of 0.5 to 0.9 μm in the composition measured by a scattering type particle size distribution analyzer. However, in this case, it is preferable that the particle size distribution shows one peak in terms of gloss and surface impact strength. That is, in the present invention,
Polymer (b1) or copolymer (b2) and copolymer (b
3) is a rubber particle obtained by dissolving in a styrene monomer (a1) and an alkyl (meth) acrylate (a2), and then copolymerizing the same to thereby obtain two types of rubber. The particle size distribution of (B) has one peak, whereby it is possible to balance gloss, rigidity and surface impact strength.

The rubber particles (B) in the present invention are:
As the raw material components for the graft copolymerization, not only the above-mentioned components but also other copolymerizable monomers can be used in combination as long as the effects of the present invention are not impaired.

The other copolymerizable monomers used herein include, for example, vinyl-cyan compounds such as (meth) acrylonitrile; (meth) acrylic acid, itaconic acid,
Polymerizable unsaturated fatty acids such as maleic acid, fumaric acid, crotonic acid, and cinnamic acid; N-methylmaleimide, N-ethylmaleimide, N-butylmaleimide, N-octylmaleimide, N-isopropylmaleimide, N-phenylmaleimide, N Maleimides such as -p-bromophenylmaleimide, No-chlorophenylmaleimide, N-cyclohexylmaleimide; unsaturated carboxylic anhydrides represented by maleic anhydride, itaconic anhydride, citraconic anhydride and the like; allylamine, Amino group-containing unsaturated compounds such as aminoethyl (meth) acrylate and aminopropyl (meth) acrylate; and acrylamide-based compounds such as acrylamide and N-methylacrylamide.

The method for producing the composition of the present invention includes:
As described above, bulk-suspension polymerization of a diene-based rubbery polymer, a styrene-based monomer (a1), an acrylic-based monomer (a2), and if necessary, other copolymerizable monomers,
Graft copolymerization may be carried out by solution polymerization or bulk polymerization, but continuous bulk polymerization is preferred from the viewpoint of productivity and cost.

Further, the polymer (b1) or the copolymer (b
2) and the copolymer (b3) are converted to a styrene monomer (a
As a specific method for compatibilizing 1) and the acrylic monomer (a2) and then graft-copolymerizing these, it is preferable to use the production method of the present invention described in detail below.

That is, a homopolymer (b) of a diene monomer
1) or a copolymer (b2) of a styrene-based monomer and a diene-based monomer having a styrene structural unit in a proportion of 15% or less on a weight basis;
A copolymer of a styrene-based monomer and a diene-based monomer (b3) having a ratio of 0 to 50%, a styrene-based monomer (a1), and an alkyl (meth) acrylate (a)
The continuous bulk polymerization of the mixed solution obtained in 2) in a continuous bulk polymerization line incorporating a tubular reactor in which a plurality of mixing elements having no moving parts is fixed is performed by the method of producing rubber particles (B). This is preferable because the diameter can be made uniform and small.

Here, the usage ratio of the rubbery polymer (b1) or copolymer (b2) and the copolymer (b3) is [(b1) or (b2)] / (b3) on a weight basis. = 95/5
When the ratio is 60/40, it is easy to adjust the particle diameter and shape of the rubber particles (B) finally obtained, that is, while increasing the salami structure content in the rubber particles (B). The average particle size can be reduced, and as a result, the desired gloss, rigidity and surface impact strength of the present invention can be achieved. The styrene content in the total weight of the polymer (b1) or the copolymer (b2) and the copolymer (b3) is 8 to 20.
It is preferable that the content be in the range of weight% from the viewpoint that the balance between gloss and surface impact strength becomes good.

A polymer (b1) or a copolymer (b2);
After the copolymer (b3) is made compatible with the styrene monomer (a1) and the alkyl (meth) acrylate (a2), the proportion of each component used in the graft copolymerization is particularly limited. (B ') /
The weight ratio of [(a1) + (a2)] is 3/97 to 16/8.
4, and the styrene monomer (a1) and (meth)
It is possible to use the alkyl acrylate (a2) in a ratio of (a1) / (a2) = 95/5 to 50/50, preferably 95/5 to 81/19 on a weight basis,
The effect of the present invention is remarkable and is preferable.

The production method of the present invention will be described in more detail. The polymer (b1) or the copolymer (b2) and the copolymer (b3)
And the styrene-based monomer (a1) and the alkyl (meth) acrylate (a2), after dissolving each raw material component in accordance with the above usage ratio, and then polymerized in one or more stirred reactors. After that, it is preferable to introduce the mixture into a tubular reactor having a static mixing element, since the uniformity of the obtained composition and the particle size of the graft rubber particles can be easily adjusted to the above-mentioned range.

Further, a continuous bulk polymerization line incorporating a tubular reactor having a static mixing element, that is, a tubular reactor having a plurality of mixing elements having no moving parts fixed therein, includes: a. A reactor, b. An initial polymerization line consisting of one or more tubular reactors having a plurality of mixing elements fixed therein with no moving parts and continuing from the stirred reactor; and c. Moving continuously from the initial polymerization line. A main polymerization line comprising one or more tubular reactors having a plurality of mixing elements having no parts fixed therein; d. Branching between the initial polymerization lines and It is preferable that the polymerization line is constituted by a reflux line and a return line.

An example of a method for producing a rubber-modified copolymer resin using the continuous bulk polymerization line will be described below with reference to FIG.

FIG. 1 is a process diagram showing an example of a continuous bulk polymerization line incorporating a tubular reactor having a static mixing element.

Polymer (b1) or copolymer (b2) supplied by plunger pump (1), copolymer (b3), styrene monomer (a1), and (meth) acrylic acid The mixed solution containing the alkyl ester (a2) as an essential component is first sent to the stirred reactor (2), and subjected to initial graft polymerization under stirring, and then the tubular reaction having a static mixing element is performed by the gear pump (3). It is sent to a circulation polymerization line (I) having vessels (4), (5) and (6) and a gear pump (7).

By combining the initial graft polymerization in the stirred reactor (2) with the circulation polymerization line (I), the rubber particles are not excessively sheared, and the rubber particles can be more efficiently refined. This is preferable in that the polymer composition in the polymerization step can be made uniform. In the initial graft polymerization in this case, the total polymerization conversion of the styrene monomer (a1) and the alkyl (meth) acrylate (a2) is 10 to 28% by weight at the outlet of the reactor (2). It is preferably carried out so as to be 14 to 24% by weight. The stirring reactor (2) includes, for example, a stirring tank reactor, a stirring tower reactor, and the like, and the stirring blade includes, for example, an anchor type, a turbine type, a screw type, a double helical type, and the like. Stirring blades.

In the present invention, a solvent may be used to reduce the viscosity of the mixed solution in the reactor. The amount of the solvent used is 5 to 20 parts by weight based on 100 parts by weight of the raw material monomers in total. . As the type of the 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 above-mentioned mixed solution in order to control the molecular weight of the rubber-modified copolymer resin. The amount of the chain transfer agent to be added is usually 0.005 to 0.
The range is 5 parts by weight. The mixed solution initially graft-polymerized under dynamic stirring as described above is then graft-polymerized while circulating in the circulation polymerization line (I), and a part of the mixed solution is continuously formed into a tubular form having a static mixing element. Reactors (8), (9) and (10) are sent to a non-circulating polymerization line (II) incorporated in series.

The rubber particles in the mixed solution in the circulating polymerization line (I) are statically mixed while circulating in the circulating polymerization line (I) and stabilized, and the particle diameter is also fixed.
In this case, the reflux ratio (R) of the mixed solution in the circulation polymerization line (I) and the total polymerization conversion rate of (a1) and (a2) are important factors. The reflux ratio R is determined in the non-circulation polymerization line (I
The flow rate of the mixed solution that is refluxed in the circulation polymerization line (I) without flowing out to I) is F1 (liter / hour), and the mixed solution flowing out of the circulation polymerization line (I) to the non-circulation polymerization line (II) is When the flow rate is F2 (liter / hour), R = F1 / F2 is usually in the range of 3 to 15, especially, the pressure loss in the tubular reactor is small, and the produced rubbery polymer particles are stable. R = 5 from the viewpoint that the diameter can be reduced and the content ratio of the styrene monomer (a1) and the alkyl (meth) acrylate (a2) in the rubber-modified copolymer resin can be kept constant. A range of 10 is particularly preferred.

In the graft polymerization in the circulation polymerization line (I), the total polymerization conversion of (a1) and (a2) at the outlet of the circulation polymerization line (I) is usually 35 to 55% by weight, The polymerization is preferably carried out 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 (I) is then supplied to the non-circulation polymerization line (II), and the styrene monomer (a1) and the ) Acrylic acid alkyl ester (a
Graft polymerization is continued until the total conversion of 2) becomes 60 to 85% by weight.

Next, the mixed solution is supplied to a Kear pump (11).
And then sent to a preheater and then to a devolatilization tank to remove unreacted monomers and solvent under reduced pressure, and then pelletize to obtain the desired rubber-modified copolymer resin. At this time, it is preferable to perform the preheating and the devolatilization under the condition that the increase in the conversion rate in the preheater and the devolatilization tank is 7% by weight or less.

As the plurality of mixing elements fixed inside the tubular reactor having the static mixing element used in the present invention, for example, the flow of the polymerization liquid flowing into the pipe is changed and the flow direction is changed, Is repeated to mix the polymerization liquid. As such a tubular reactor, for example, SMX type, SMR
Examples thereof include a Sulzer-type tubular mixer, a Kenix-type static mixer, and a Toray-type tubular mixer. Among them, SMX-type and SMR-type Sulzer-type tubular mixers are particularly preferable.

The number of these tubular reactors to be incorporated in the circulation polymerization line (I) or the non-circulation polymerization line (II) is particularly different in the case of the above-mentioned tubular reactor because it depends on the length thereof, the structure of the mixing element, and the like. Without limitation, the tubular reactor having four or more mixing elements
１５15, preferably 6-10 are used in combination. Among them, the number of the tubular reactors to be 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 free radicals when decomposed as a polymerization initiator, if necessary, because grafting and reaction can be promoted at a relatively low temperature. The addition amount is in the range of 0.005 to 0.04 parts by weight based on 100 parts by weight of the total amount of the raw material monomers.

The organic peroxide used here is preferably one having a temperature at which the half-life becomes 10 hours at 75 to 170 ° C., and specific examples thereof include 1,1-di-t-butylperoxycyclohexane, , 1-Di-t-butylperoxy-
3,3,5-trimethylcyclohexane, 1,1-di-t-butylperoxy-2-methylcyclohexane, 2,2-bis (4,
4-di {-tert-butylperoxycyclohexyl) propane, 2,2-di-tert-butylperoxyoctane, n-butyl-4,4-di-tert-butylperoxyvalerate, 2,2-di -Peroxy ketals such as t-butyl peroxybutane; t-butyl peroxy acetate, t-butyl peroxy-3,5,5-trimethylhexanoate, t-butyl peroxy laurate, t-butyl peroxy Oxybenzoate, t-butyl peroxymetharate, di-t-butyl diperoxyisophthalate, 2,5-dimethyl-2,5-
Dibenzoyl peroxyhexane, t-butyl peroxymaleic acid, t-butyl peroxyisopropyl carbonate, di-t-butyl peroxide, dicumyl peroxide, t-butyl hydroperoxide,
Peroxyesters such as cumene hydroperoxide and the like can be mentioned, and these are used alone or in combination of two or more.

As described above, the styrene resin composition thus obtained has a toluene insoluble content at 25 ° C. of 13 to 20% by weight and a toluene swelling index at 25 ° C. of 10%.
To 15 and the ratio [25 ° C.
Of toluene-insoluble matter content / toluene swelling index at 25 ° C.] is 1.2 to 2.5.

The copolymer of the matrix phase (a1) and (a2) in the resin has a weight average molecular weight (Mw) of 140,000 to 200,000 and a weight average molecular weight (M
w) and the number average molecular weight (Mn) ratio Mw / Mn is 1.8 to
2.5 are preferred, and among them, the weight average molecular weight (M
When w) is 160,000 to 180,000, it is particularly preferable because it has excellent impact resistance, rigidity and chemical resistance.

The gloss of a molded article can be further improved by using a silicone oil in addition to the copolymer (A) and the rubber particles (B) in the composition of the present invention. Examples of the silicone oil include, but are not particularly limited to, polydimethylsiloxane, polymethylphenylsiloxane, and the like. The method for blending the silicone oil is not particularly limited, but may be a polymer (b1) or a copolymer (b2), a copolymer (b3), a styrene monomer (a1), an alkyl acrylate, It is preferable to dissolve in a raw material mixed solution containing the ester (a2) and carry out the graft copolymerization described in detail.

In addition to the copolymer (A) and the rubber particles (B), as long as the rigidity and the surface impact property are not impaired,
By including a thermoplastic block copolymer (C) of a styrene-based monomer and a diene-based monomer having a styrene structural unit in a proportion of 30 to 50% by weight, particularly a co-extruded sheet or film The impact strength in applications such as the above can be improved. As the styrene-based monomer and the diene-based monomer constituting the copolymer (C), any of those exemplified in the above (b1) to (b3) can be used. As the compounding method, as in the case of the silicone oil, a method of dissolving in a mixed solution of the polymerization raw materials and performing the polymerization, or after producing a composition of the copolymer (A) and the rubber particles (B), Although there is a method of melt-kneading with an extruder, the latter method of melt-kneading is preferable because the amount of the copolymer (C) can be easily adjusted.

In the present invention, the copolymer (A)
In addition to the rubber particles (B) and in addition, isoparaffin-based polymer is used in combination to impart plasticity,
In addition to increasing the rigidity and oil resistance of the molded product, the gloss of the molded product can be dramatically improved.

The isoparaffin-based polymer is not particularly limited, but is a raw material polymer mainly composed of an isoolefin represented by isobutene, isopentene, isohexene, isoheptene, isooctene, etc. Copolymers on seeds, copolymers of these isoolefins and other olefins or modified products thereof, and the like, the specific structure of which is a structure having a main structure having an isoalkylene unit as a repeating unit, Copolymers of isoalkylene, 1-alkene, and 2-alkene, or maleic acid-modified or phosphorus pentasulfide-modified structures having a repeating unit of an isoalkylene unit are exemplified.

Among these isoolefin-based polymers, isobutylene and 1-butylene are particularly preferred from the viewpoints of oil resistance and plasticizing effect.
A copolymer of butene and 2-butene, or polyisobutylene is preferred. In the former copolymerization, usually,
Since the raw material isobutylene contains monomers such as 1-butene and 2-butene in addition to isobutylene, they may be used as a liquid viscous liquid obtained by polymerizing these.

The obtained isoparaffin-based polymer may be one in which unsaturated bonds in the molecule are not hydrogenated or those in which hydrogenation is performed. Further, in order to obtain a modified isoolefin polymer, the isoolefin is polymerized together with an unsaturated bond-containing monomer such as maleic acid or phosphorus pentasulfide, or the isoolefin is polymerized. May be caused to react with the unsaturated bond existing in the above.

As for the method of compounding the isoparaffin-based polymer, it is preferable to carry out the polymerization by dissolving it in a raw material solution for polymerization, like the other compounding components.

These isoparaffinic polymers are not particularly limited in molecular weight and the like, but are usually
Viscosity by BM type viscometer is 20 to 10,000 cps
(38 ° C.), preferably 50 to 3,
The range of 000 cps is excellent in mixing dispersibility when mixed with the resin (A) or compatibility with each of the components (a1) to (a3), and is also preferable from the viewpoint of impact strength, gloss and elongation of a molded product. . Further, for the same reason, the average molecular weight is 200 to 3,
000 is preferred.

The composition of the present invention may further contain, if necessary, a plasticizer such as mineral oil, an antioxidant, a chain transfer agent, a release agent such as a long-chain fatty acid, an ester thereof or a metal salt thereof, and the like. A known additive such as described above may be used in combination. As for these compounding methods, as in the case of each of the above-mentioned compounding components, a method of dissolving in a polymerization raw material solution and performing polymerization is preferable.

The styrenic resin composition of the present invention obtained in this manner may further contain commonly used antioxidants, plasticizers, ultraviolet absorbers, lubricants, flame retardants, antistatic agents, foaming agents, reinforcing materials and the like. Can be blended.

As specific examples, for example, mineral oil,
Ester plasticizers, polyester plasticizers, organic polysiloxanes, higher fatty acids and metal salts thereof, hindered phenolic antioxidants, glass fibers, etc., can be used alone or in combination. In addition, specific examples of additives generally used for improving weather resistance include:
Benzotriazole-based or benzophenone-based ultraviolet absorbers represented by Tinuvin P, Tinuvin 327 (Nippon Ciba Geigy Co., Ltd.), Sumilizer-GM or GS (Sumitomo Chemical Co., Ltd.), Irganox 1076
(Nippon Ciba Geigy Co., Ltd.), a hindered phenol-based antioxidant represented by SANOL LS-770, a hindered amine-based light stabilizer, a phosphorus-based antioxidant represented by trisnonylphenyl phosphite, Organic sulfur-based antioxidants represented by dimyristyl thiodipropionate and the like can be mentioned.

The styrenic resin composition of the present invention comprises:
Injection molding, monoaxial extrusion molding suitable for sheet and film molded products, biaxial stretching extrusion molding, inflation extrusion molding, profile extrusion molding, vacuum molding, pressure molding, blow molding, etc. Can be used. Its applications are wide-ranging, such as refrigerator interior materials,
TV and air-con housings, cleaner boxes,
Parts of household appliances and appliances such as copiers, printers, etc.
Used as various parts of OA equipment such as facsimile, personal computer, etc .; food containers; medical equipment parts; food sheet packaging containers and the like.

The styrenic resin composition of the present invention further comprises:
If necessary, polystyrene resin, rubber-modified polystyrene resin, AS resin, ABS resin, styrene-methyl methacrylate copolymer resin, rubber-modified styrene-methyl methacrylate copolymer resin, (meth) acrylic resin, styrene-maleic anhydride A thermoplastic resin such as a polymer resin, a styrene- (meth) acrylic acid copolymer resin, a polycarbonate resin, or a vinyl chloride resin may be appropriately added. Among these, particularly polystyrene resin, rubber-modified polystyrene resin, styrene-methyl methacrylate copolymer resin,
Rubber-modified styrene-methyl methacrylate copolymer resin,
It is preferable because it has excellent compatibility with the rubber-modified copolymer resin of the present invention.

The styrenic resin composition of the present invention comprises
Good compatibility with polystyrene resin, rubber-modified polystyrene resin, styrene-methyl methacrylate copolymer resin, and rubber-modified styrene-methyl methacrylate copolymer resin, which occurs during the molding process of the rubber-modified copolymer resin of the present invention. It is suitable for recycling runner parts and skeleton parts. Further, as another application, the resin composition of the present invention is added to a blend of a rubber-modified polystyrene resin and a rubber-modified styrene-methyl methacrylate copolymer resin to act as a compatibilizer, thereby preventing a decrease in physical properties of the blend. You can also.

[0070]

The present invention will be described more specifically with reference to the following examples. However, all parts in the examples are parts by weight and%
All indicate% by weight.

The average particle size of the rubbery polymer, the shape of the dispersed rubber particles, the method for measuring the toluene-insoluble content and the swelling index with toluene, and the method for evaluating the physical properties are described below.

1. Average particle diameter of rubbery polymer in resin DMF was used as a dispersion medium, and the volume-based median diameter of the composition measured by a scattering type particle size distribution analyzer was measured. 2. Shape of rubbery polymer in resin Transmission electron micrograph (100
(× 00), the shape of the dispersed rubber was observed for 1000 particles in the photograph, and the number of those having a salami structure and the number of those having a core-shell structure were determined.

3. Toluene insoluble content and swelling index due to toluene 1 g of the styrene resin composition was precisely weighed and 100 m
The solution was transferred to a centrifuge tube, centrifuged at 12,000 rpm for 30 minutes at 10 ° C. or lower, and the supernatant was removed by decantation, followed by swelling with toluene. Measure the weight of the insoluble matter. Next, it is dried for 24 hours in a vacuum dryer at 60 ° C., the weight of the obtained toluene insoluble component is measured, and the content of the toluene insoluble component is calculated by the following equation.

[0074]

Formula 2: Content of toluene-insoluble matter = [weight of toluene-insoluble matter after drying / weight of styrene resin composition] × 100 (% by weight) The swelling index is calculated by the following equation.

[0075]

[Formula 3] Swelling index = weight of swollen toluene-insoluble matter / weight of dried toluene-insoluble matter

4. Fluidity The value of MFR was measured according to JIS K-7210.

5. Izod impact value Notched was measured according to JIS K-6871. In addition, as an evaluation of practical strength, using a test piece having a width of 3.2 mm,
Align the plane of symmetry of the notch with the upper surface of the specimen support,
The test piece was attached to the support so that the notch was on the back side in the direction of impact, and the reverse notch was measured. 6. Surface Impact Strength A sheet having a thickness of 0.4 mm was prepared using a 30 mm single screw extruder, and the DuPont impact strength was measured according to JIS K-7211.

7. Flexural strength and flexural modulus The values were determined based on JIS K-7113 at a test speed of 50 mm / min. However, a tensile test piece described in JIS K-6732 was used as the test piece. 8. Gloss Dumbbell specimens are manufactured by injection molding, and the gloss of the flat surface on the gate side and the flat surface on the end side of the test piece are measured according to JIS Z-874.
1 (incident angle 60 degrees).

9. Chemical resistance test of molded article A gravure ink containing ethyl acetate and IPA as main components was applied to the surface of JIS No. 1 dumbbell (thickness: 3 mm, total length: 175 mm). One end of this test piece was fixed, a weight of 200 g was hung on the opposite end, and the test piece was allowed to stand at 23 ° C. and 50% humidity for a certain period of time to observe the appearance, and evaluated according to the following criteria.

：: Number of cracks generated in test piece 0 to 15 Δ: Number of cracks generated in test piece 16 to 40 ×: Test piece fractured

Example 1 In this example, devices arranged as shown in FIG. 1 were used. A mixed solution containing styrene, methyl methacrylate, a rubbery polymer and a solvent was sent to a 20-liter stirred reactor (2) by a plunger pump (1) and subjected to initial graft polymerization under dynamic mixing by a stirring blade. . Next, this mixed solution is sent to the circulation polymerization line (I) by the gear pump (3). The circulation polymerization line (I) has a 2.5 inch inner diameter tubular reactor (30 built-in SMX static mixers and static mixing elements manufactured by Gebrüder Sulzer, Switzerland) in order from the inlet (4), (5) and (6) Pump (7) for circulating mixed solution with water
It is composed of Between the tubular reactor (6) and the gear pump (7) there is an outlet following the acyclic polymerization line (II). The tubular reactors (8), (9) and (1) similar to the above are sequentially supplied to the non-circulation polymerization line (II) from the inlet.
0) and the gear pump (11) are connected in series.

Styrene-butadiene copolymer rubber [5% styrene solution viscosity at 25 ° C. (hereinafter abbreviated as 5% SV): 32 centipoise, styrene / butadiene weight ratio: 5/95] 6.4 parts, styrene-butadiene copolymer A mixed solution comprising 1.6 parts of a polymerized rubber [5% SV: 10 centipoise, styrene / butadiene weight ratio: 38/62], 85 parts of styrene, 15 parts of methyl methacrylate and 10 parts of ethylbenzene was prepared, and further chain-transferred. As an agent, 0.02 parts of n-dodecyl mercaptan per 100 parts of the monomer mixture and 0.025 parts of t-butyl peroxyisopropyl carbonate as an organic peroxide per 100 parts of the monomer mixture; Five parts of a mineral oil (S-250, manufactured by Shima Trading Co., Ltd.) were added, and continuous bulk polymerization was performed using the above apparatus under the following conditions.

Continuous supply of mixed solution: 10 liter / hour Reaction temperature in stirred reactor (2): 120 ° C. Reaction temperature in circulating polymerization line (I): 135 ° C. Acyclic polymerization line (II) Reaction temperature: 140-160
C. Reflux ratio: R = F1 / F2 = 5 The mixed solution obtained by polymerization was heated to 225 ° C. with a heat exchanger, and volatile components were removed under a reduced pressure of 50 mmHg. A resin composition was obtained.

The rubber-modified copolymer resin composition thus obtained was injection molded to prepare test pieces, and various physical properties were measured. Table 1 shows the analytical data and measurement results of physical properties of the resin.

The styrene resin composition obtained in Example 1 was taken with a transmission electron microscope photograph (100
FIG. 2).

Example 2 Styrene-butadiene copolymer rubber [5% SV: 32 centipoise, styrene / butadiene weight ratio: 5/95] 6.
4 parts, styrene-butadiene block copolymer rubber [5%
SV: 32 centipoise, styrene / butadiene weight ratio:
40/60] A styrene resin composition of the present invention was obtained in the same manner as in Example 1 except that a mixed solution consisting of 1.6 parts, 85 parts of styrene, 15 parts of methyl methacrylate and 10 parts of ethylbenzene was used. Injection molded articles were prepared in the same manner as in Example 1, and various physical properties were measured. The results are shown in Table 1.

Example 3 5.6 parts of low-cis polybutadiene [5% SV: 35 centipoise], styrene-butadiene copolymer rubber [5%
SV: 10 centipoise, styrene / butadiene weight ratio: 38/62] The procedure of Example 1 was repeated, except that a mixed solution consisting of 2.4 parts, 90 parts of styrene, 10 parts of methyl methacrylate and 10 parts of ethylbenzene was used. The styrene resin composition of the invention was obtained. Injection molded articles were prepared in the same manner as in Example 1, and various physical properties were measured. The results are shown in Table 1.

Example 4 Styrene-butadiene copolymer rubber [5% SV: 32 centipoise, styrene / butadiene weight ratio: 5/95]
4 parts, styrene-butadiene copolymer rubber [5% SV: 1
0 centipoise, styrene / butadiene weight ratio: 38/62
1.6 parts, styrene 85 parts, methyl methacrylate 1
A mixed solution consisting of 5 parts and 10 parts of ethylbenzene was prepared. Further, as a chain transfer agent, 1.5 parts of n-dodecyl mercaptan and 0.0 parts of n-dodecyl mercaptan per 100 parts of the monomer mixture were replaced with mineral oil. A styrenic resin composition of the present invention was obtained in the same manner as in Example 1 except that an isoparaffin copolymer (Idemitsu Petrochemical, Idemitsu Polybutene 35R) was added. Injection molded articles were prepared in the same manner as in Example 1, and various physical properties were measured. The results are shown in Table 1.

Example 5 Styrene-butadiene copolymer rubber [5% SV: 32 centipoise, styrene / butadiene weight ratio: 5/95]
4 parts, styrene-butadiene copolymer rubber [5% SV: 1
0 centipoise, styrene / butadiene weight ratio: 38/62
1.6 parts, styrene 83 parts, methyl methacrylate 1
5 parts, 2 parts of butyl acrylate and 10 parts of ethylbenzene
Of a styrene-based resin of the present invention in the same manner as in Example 1 except that a mixed solution consisting of 1 part by weight was prepared, and 0.025 part of n-dodecyl mercaptan was added to 100 parts of the monomer mixture as a chain transfer agent. A composition was obtained. Injection molded articles were prepared in the same manner as in Example 1, and various physical properties were measured. The results are shown in Table 1.

Example 6 Styrene-butadiene copolymer rubber [5% SV: 32 centipoise, styrene / butadiene weight ratio: 5/95]
4 parts, styrene-butadiene copolymer rubber [5% SV: 1
0 centipoise, styrene / butadiene weight ratio: 38/62
1.6 parts, styrene 65 parts, methyl methacrylate 3
0 parts, 5 parts of butyl acrylate and 10 parts of ethylbenzene
Of a styrene-based resin of the present invention in the same manner as in Example 1 except that a mixed solution consisting of 1 part by weight was prepared, and 0.025 part of n-dodecyl mercaptan was added to 100 parts of the monomer mixture as a chain transfer agent. A composition was obtained. Injection molded articles were prepared in the same manner as in Example 1, and various physical properties were measured. The results are shown in Table 1.

Comparative Example 1 Low-cis polybutadiene [5% SV: 35 centipoise] 8 parts, styrene 92 parts, and ethylbenzene 10
Of a monomer solution as a chain transfer agent, and 0.01 part of n-dodecyl mercaptan as a chain transfer agent and 0.02 parts as an organic peroxide based on 100 parts of the monomer mixture. Parts of t-butyl peroxybenzoate, 1.5 parts of mineral oil (manufactured by Shima Trading Co., Ltd.
S-250) was added, and continuous bulk polymerization was carried out using the above apparatus under the following conditions.

Continuous supply amount of mixed solution: 10 liter / hour Reaction temperature in stirred reactor (2): 130 ° C. Reaction temperature in circulating polymerization line (I): 135 ° C. Acyclic polymerization line (II) Reaction temperature at 140-170
C. Reflux ratio: R = F1 / F2 = 5 The mixed solution obtained by polymerization was heated to 225 ° C. with a heat exchanger, and volatile components were removed under a reduced pressure of 50 mmHg. A resin composition was obtained.
Table 1 shows the analysis data and the measurement results of the physical properties.

Comparative Example 2 Styrene-butadiene copolymer rubber [5% SV: 10 centipoise, styrene / butadiene weight ratio: 38/62]
10 parts, styrene 85 parts, methyl methacrylate 15 parts,
A styrene-based resin composition was obtained in the same manner as in Example 1, except that a mixed solution comprising ethylbenzene and 12 parts of ethylbenzene was used. Injection molded articles were prepared in the same manner as in Example 1, and various physical properties were measured. The results are shown in Table 1.

Comparative Example 3 Styrene-butadiene copolymer rubber [5% SV: 10 centipoise, styrene / butadiene weight ratio: 38/62]
10 parts, styrene 48 parts, methyl methacrylate 52 parts,
A styrene-based resin composition was obtained in the same manner as in Example 1, except that a mixed solution consisting of ethylbenzene and 10 parts of ethylbenzene was used. Injection molded articles were prepared in the same manner as in Example 1, and various physical properties were measured. In addition, about the measurement of gloss, the obtained resin composition was melt-kneaded using an extruder with titanium white, and was measured as an opaque molded product. The results are shown in Table 1.

Comparative Example 4 A mixed solution consisting of 8 parts of low-cis polybutadiene [5% SV: 25 centipoise], 92 parts of styrene, and 10 parts of ethylbenzene was used. Further, as a chain transfer agent, 100 parts of the monomer mixture was used. A styrene resin composition was obtained in the same manner as in Comparative Example 1 except that 0.015 parts of n-dodecyl mercaptan was used. Injection molded articles were prepared in the same manner as in Comparative Example 1, and various physical properties were measured. The results are shown in Table 2.

Comparative Example 5 Styrene-butadiene copolymer rubber [5% SV: 32 centipoise, styrene / butadiene weight ratio: 5/95] 8
Part, styrene 30 parts, methyl methacrylate 65 parts, butyl acrylate 5 parts, and a mixed solution consisting of 14 parts of ethylbenzene. Further, as a chain transfer agent, 0.025 part of n was used with respect to 100 parts of the monomer mixture. -A styrene resin composition was obtained in the same manner as in Example 1 except that dodecyl mercaptan was used. Injection molded articles were prepared in the same manner as in Example 1, and various physical properties were measured. In addition, about the measurement of gloss, the obtained resin composition was melt-kneaded with titanium white using an extruder, and was measured as an opaque molded product. The results are shown in Table 2.

[0097]

[Table 1]

[0098]

[Table 2]

[0099]

According to the present invention, it is possible to provide a styrene resin composition having excellent gloss, rigidity and surface impact strength. In particular, when the acrylic component in the matrix is small,
Further, while maintaining the performance of the present invention such as gloss, impact strength and rigidity of the molded product, it is possible to use the recycled product by blending the recovered product with polystyrene, and the molded product has significantly improved chemical resistance. . Accordingly, the styrenic resin composition of the present invention can be suitably used for various molded products, but when it is made into a sheet molded product, its gloss, impact resistance and rigidity are remarkably excellent.

[Brief description of 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.

FIG. 2 is a transmission electron micrograph (× 10000) of the styrenic resin composition of the present invention obtained in Example 1 by an ultra-thin section method.

[Explanation of symbols]

(1): Plunger pump (2): Stirred reactor (3): Gear pump (4): Tubular reactor with static mixing element (5): Tubular reactor with static mixing element (6): Static (7): Gear pump (8): Tubular reactor with static mixing element (9): Tubular reactor with static mixing element (10): Tubular with static mixing element Reactor (11): Gear pump (I): Circulation polymerization line (II): Non-circulation polymerization line

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C08F 2/02 C08F 2/02 279/06 279/06

Claims (14)

[Claims] 1. A copolymer of a styrene monomer and an acrylic monomer (A) is used as a matrix phase, and a diene rubber polymer is made of a styrene monomer and an acrylic monomer. In a styrene-based resin composition containing dispersed rubber particles (B) obtained by graft copolymerization, a copolymer (A) is obtained by combining a styrene-based monomer and an alkyl (meth) acrylate on a weight basis. / Latter = 9
5/5 to 50/50, wherein the rubber particles (B) have a volume-based median diameter in the composition measured by a scattering type particle size distribution analyzer of 0.5 to 50/50. 0.9μ
m, and the composition has a value of [toluene-insoluble content at 25 ° C./toluene swelling index at 25 ° C.] of 1.2 to 2.5. -Based resin composition. 2. As the rubber particles (B), the rubber particles (B1) having a salami structure and the rubber particles (B2) having a core-shell structure coexist, and the particles are shown in a transmission electron micrograph (× 10000). When the number of the rubber particles (B1) and the number of the rubber particles (B2) when observing 1,000 particles are (B
The composition according to claim 1, wherein 1) / (B2) = 70/30 to 95/5. 3. The composition according to claim 1, wherein the rubber particles (B) have a volume-based particle size distribution measured by a scattering type particle size distribution analyzer showing one peak. 4. The copolymer (A) is obtained by copolymerizing a styrene monomer and an alkyl (meth) acrylate in a ratio of 95/5 to 81/19 on a weight basis. The composition according to claim 1, wherein the composition is: 5. The copolymer (A) has a weight average molecular weight of 14
5. The composition according to claim 4, wherein the composition is 10,000 to 200,000. 6. The composition according to claim 1, further comprising an isoparaffin-based polymer in addition to the copolymer (A) and the rubber particles (B).
A composition according to any one of the preceding claims. 7. The composition according to claim 1, further comprising a silicone oil in addition to the copolymer (A), the rubber particles (B1) and the rubber particles (B2). 8. A copolymer of a styrene monomer and a diene monomer having a styrene structural unit in a proportion of 30 to 50% by weight in addition to the copolymer (A) and the rubber particles (B). 2. The composition according to claim 1, which contains a thermoplastic block copolymer (C).
A composition according to any one of claims 1 to 7. 9. A homopolymer (b1) of a diene monomer,
Or a copolymer (b2) of a styrene-based monomer and a diene-based monomer having a styrene structural unit in a proportion of 15% or less by weight, and 20 to 50% by weight of the styrene structural unit. A mixed solution of a copolymer (b3) of a styrene-based monomer and a diene-based monomer having a ratio, a styrene-based monomer (a1), and an alkyl (meth) acrylate (a2), A method for producing a styrenic resin, comprising performing continuous bulk polymerization in a continuous bulk polymerization line incorporating a tubular reactor having a plurality of mixing elements having no movable parts fixed therein. 10. A homopolymer of a diene monomer (b)
1) or a copolymer (b2) of a styrene-based monomer and a diene-based monomer having a styrene structural unit content of 15% or less by weight, and 20 to 50 styrene structural units by weight. % Of a copolymer of a styrene monomer and a diene monomer (b3), a styrene monomer (a1), and an alkyl (meth) acrylate (a2). The production method according to claim 9, wherein the polymerization is performed in one or more agitated reactors and then introduced into a tubular reactor. 11. A homopolymer of a diene monomer (b)
1) or a copolymer (b2) of a styrene-based monomer and a diene-based monomer having a styrene structural unit content of 15% or less by weight, and 20 to 50 styrene structural units by weight. % Of a copolymer of a styrene-based monomer and a diene-based monomer (b3), a styrene-based monomer (a1), and an alkyl (meth) acrylate (a2). A. A stirred reactor; and b. An initial polymerization line consisting of one or more tubular reactors having a plurality of mixing elements that are continuous from the stirred reactor and have no moving parts. C. A main polymerization line consisting of one or more tubular reactors in which a plurality of mixing elements continuing from the initial polymerization line and having no moving parts are fixed, and d. Between the initial polymerization line and the main polymerization line. First branch Using a polymerization line composed of a reflux line returning into the polymerization line, a part of the initial polymerization liquid stream flowing out of the initial polymerization line is refluxed through the reflux line, while the initial polymerization liquid stream that has not been refluxed is subjected to main polymerization. The production method according to claim 10, wherein the polymerization is performed in a line. 12. A homopolymer of a diene monomer (b)
1) or a copolymer (b2) of a styrene-based monomer and a diene-based monomer having a styrene structural unit content of 15% or less by weight, and 20 to 50 styrene structural units by weight. % Of a copolymer (b3) of a styrene monomer and a diene monomer having a ratio of [(b1) or (b2)] / (b3) =
11. The composition according to claim 9, wherein the composition is used in a ratio of 95/5 to 60/40.
Or the production method according to 11. 13. A polymer (b1) or a copolymer (b2)
And, in addition to the copolymer (b3), the styrene-based monomer (a1), and the alkyl (meth) acrylate (a2),
Further, it contains an isoparaffin polymer.
The manufacturing method according to any one of the above. 14. A polymer (b1) or a copolymer (b2)
And a copolymer (b3), a styrene monomer (a1), and an alkyl (meth) acrylate (a2), and further contain a silicone oil. The production method described in 1.