JP2003096255A - Aromatic vinyl resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resin composition in which a layered compound is very finely dispersed in an aromatic vinyl resin. SOLUTION: The aromatic vinyl resin composition is prepared by adding a treated layered compound obtained by treating the layered compound with a polyether structure-containing compound to the aromatic vinyl resin having an acid value in the range of 1-200 mg KOH/g. When the polyether structure- containing compound is the compound also having an aromatic hydrocarbon group in a molecule, the resin composition having better dispersibility can be obtained.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an aromatic vinyl-based resin obtained by adding a treatment layered compound treated with a polyether structure-containing compound to an aromatic vinyl-based resin having an acid value within a specific range. It relates to a composition.

[0002]

2. Description of the Related Art Polystyrene, styrene-butadiene copolymer, ABS resin, MBS resin, AES resin, ASA
Aromatic vinyl resins such as resins and styrene-based thermoplastic elastomers have excellent heat resistance, chemical resistance, weather resistance, mechanical properties, electrical properties, etc., so they are injection molding materials, blow molding materials, foam molding materials. , Etc. are used in many industrial applications, but higher mechanical properties and heat resistance are required. In order to meet such requirements, attempts have generally been made to improve the composition by blending various inorganic particles, but there has been a problem that the surface appearance of the product is impaired thereby.
Such defects of inorganic particles are generally considered to be caused by poor dispersion of the inorganic particles or an excessively large dispersed particle size, and a technique for finely dispersing the inorganic particles has been desired. It is also known that mechanical properties can generally be improved by strengthening with a fibrous inorganic reinforcing agent.
However, the resin composition reinforced with the fibrous reinforcing agent, when the molding process is repeatedly performed, the reinforcing efficiency deteriorates because the fibrous reinforcing agent is broken during the molding process.
There was a problem that the physical properties were significantly deteriorated when the recycling was repeated. Among the non-fibrous inorganic particles, regarding the layered compound, particularly the layered silicate, as a technique for easily cleaving the layer of the layered silicate to facilitate fine dispersion, JP-A-9-118518 discloses polyvinyl A technique of intercalating a polymer compound (intercalant polymer) such as pyrrolidone between layers of a layered silicate to form an intercalation compound is disclosed. However, in the above invention, although the intercalation compound is disclosed, the technique of cleaving the intercalation compound to finely disperse it into the aromatic vinyl-based resin is not disclosed, and the layered compound is contained in the aromatic vinyl-based resin. It was difficult to finely disperse. In addition, JP-A-1
0-259016 and JP-A-10-310420.
The publication discloses a layered silicate treated with a dispersion stabilizer having a polyether chain as a main chain. However, although the above-mentioned invention is said to be applicable to thermoplastic polyester resin, polyamide resin, polycarbonate resin, polyolefin resin, etc., a technique for finely dispersing it in an aromatic vinyl resin is not disclosed. ,
It was difficult to finely disperse the layered compound in the aromatic vinyl resin.

[0003]

SUMMARY OF THE INVENTION The object of the present invention is to improve such conventional problems, and by finely dispersing a layered compound in an aromatic vinyl resin, an aromatic vinyl resin having an excellent physical property balance. To provide a composition.

[0004]

Means for Solving the Problems As a result of intensive studies for achieving the above-mentioned object, the present inventors have completed the present invention. That is, the present invention has an acid value of 1 to 200 mg KO.
An aromatic vinyl-based resin having a range of H / g, which is obtained by treating a layered compound with a polyether structure-containing compound represented by the following general formula (1), and which is obtained by adding a treated layered compound. Vinyl resin composition. ^{- (- R 1 -O-) n-} (1) ( wherein, R ¹ is either a divalent hydrocarbon group having 1 to 5 carbon atoms, be different even they are respectively the same Well, R ¹ may contain a hydroxyl group, 1 ≦ n
≦ 1000. ) In a preferred embodiment, the aromatic vinyl resin composition as described above, wherein the polyether structure-containing compound is a compound having an aromatic hydrocarbon group in the molecule. A further preferred embodiment is characterized in that in a polar solvent containing water or water, the layered compound is treated by mixing the polyether structure-containing compound and the layered compound to obtain a treated layered compound, The aromatic vinyl resin composition according to any one of the above. As a further preferred embodiment, the aromatic vinyl resin composition according to any one of the above items, wherein the layered compound in the resin composition has an average layer thickness of 50 nm or less. In a further preferred embodiment, the maximum layer thickness of the layered compound in the resin composition is 200.
The aromatic vinyl-based resin composition according to any one of the above items, wherein the aromatic vinyl-based resin composition has a thickness of not more than nm. A more preferred embodiment relates to the aromatic vinyl resin composition according to any one of the above items, wherein the layered compound is a layered silicate.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION The aromatic vinyl resin used in the present invention is a polymer obtained by polymerizing an aromatic vinyl monomer, or an aromatic vinyl monomer and copolymerizable with these. It is a copolymer obtained by copolymerizing another vinyl-based monomer. Aromatic vinyl monomers include styrene, o-methylstyrene, p-methylstyrene, m-methylstyrene, α-methylstyrene, 2,4-dimethylstyrene, monochlorostyrene, dichlorostyrene, monobromostyrene, dibromo. Examples include styrene, tribromostyrene, pt-butylstyrene, ethylstyrene, and divinylbenzene. Among these, styrene and α-methylstyrene are preferably used because of their ease of reaction and availability. These are 1
They may be used alone or in combination of two or more. Other vinyl-based monomers copolymerizable with the aromatic vinyl-based monomer include, for example, (meth) acrylic acid alkyl ester such as methyl methacrylate, ethyl methacrylate, n-butyl methacrylate, and methacrylic acid i. -Propyl, t-butyl methacrylate, 2-ethylhexyl methacrylate, stearyl methacrylate, methyl acrylate, ethyl acrylate, n-butyl acrylate, i-acrylate
Butyl, t-butyl acrylate, 2-ethylhexyl acrylate, stearyl acrylate, and the like, unsaturated nitrile compounds such as acrylonitrile and methacrylonitrile, and maleimide compounds such as maleimide, N-methylmaleimide, and N. -Ethylmaleimide, N
-Phenylmaleimide, N-cyclohexylmaleimide and the like, and other vinyl-based monomers include acrylamide and vinyl acetate. These may be used alone or in combination of two or more.

When impact resistance is required, the aromatic vinyl resin is used as an aromatic vinyl resin in the presence of a rubbery polymer, or an aromatic vinyl monomer and a copolymer thereof. It is preferred to use part or all of the graft copolymer obtained by polymerizing a mixture of possible monomers. Examples of the rubber-like polymer include polybutadiene rubber, styrene-butadiene rubber (SBR), acrylonitrile-butadiene rubber (NBR), butyl acrylate-butadiene rubber, ethylene-propylene rubber, acrylic rubber and silicone rubber. The rubbery polymers may be used alone or in combination of two or more. The amount of the rubber-like polymer in each component is not particularly limited, but the proportion of the rubber-like polymer in the whole thermoplastic composition is preferably 70 parts by weight or less. If the amount of the rubber-like polymer in the thermoplastic resin composition exceeds 70 parts by weight, the molding process tends to be difficult.

When impact resistance is required, an aromatic vinyl-based thermoplastic elastomer may be used as the aromatic vinyl-based resin in addition to the above method. The aromatic vinyl-based thermoplastic elastomer is generally a block copolymer of an aromatic vinyl-based monomer and a conjugated diene-based monomer. As the conjugated diene-based monomer, butadiene,
Isoprene or the like is used. Examples of the block state include a diblock copolymer, a triblock copolymer, a multiblock copolymer, a radial block copolymer, and the like, and any of these block copolymers may be used. The content of the aromatic vinyl-based monomer in the aromatic vinyl-based thermoplastic elastomer is not particularly limited, but is preferably 5 to 70% by weight from the viewpoint of moldability and mechanical properties of the obtained resin composition. , And more preferably 10 to 5
It is 0% by weight. If the content of the aromatic vinyl-based monomer in the aromatic vinyl-based thermoplastic elastomer is less than 5% by weight, moldability tends to be insufficient. If the content of the aromatic vinyl-based monomer in the aromatic vinyl-based thermoplastic elastomer exceeds 70% by weight, the properties as an elastomer tend to be insufficient.

Further, as the aromatic vinyl-based thermoplastic elastomer, a copolymer obtained by partially or completely saturating the double bonds in the main chain by hydrogenating the conjugated diene portion of the block copolymer. Can also be used. Preferred examples of the aromatic vinyl-based thermoplastic elastomer include polystyrene-polybutadiene-polystyrene copolymer, polystyrene-polyisoprene-polystyrene copolymer, and polystyrene-poly (ethylene-butylene)-.
Polystyrene copolymer, polystyrene-poly (ethylene-butylene) -polystyrene copolymer, polystyrene-
Examples thereof include polyisobutylene-polystyrene copolymer, polystyrene-polyisobutylene copolymer, and the like.

The acid value of the aromatic vinyl resin is 1 to 200.
The range of mgKOH / g is necessary to more easily and finely disperse the layered compound. Here, the acid value is a value measured according to JIS K0070.
When the acid value of the aromatic vinyl resin is less than 1, the dispersibility of the layered compound decreases, and when the acid value exceeds 200, the thermal stability of the entire resin decreases, which is not preferable. Preferably 3 to 1
50 mgKOH / g, more preferably 5 to 100
It is mgKOH / g. Acid value of aromatic vinyl resin is 1
~ 200mgKOH / g, the method of copolymerizing a monomer containing a carboxylic acid and / or sulfonic acid at the time of resin production, the monomer is easily obtained and the resin is easily produced, In addition, the obtained resin is excellent in the balance of physical properties, which is preferable.

Among the monomers suitable for copolymerization, the unsaturated acid compound is acrylic acid, methacrylic acid, itaconic acid, maleic acid and the like, and the unsaturated carboxylic acid anhydride is maleic anhydride and itaconic anhydride. Examples thereof include acids and citraconic anhydride. These may be used alone or in combination of two or more. However, the unsaturated carboxylic acid anhydride may have an acid value of zero when used as it is. Therefore, at the time of the monomer, or after completion of the copolymerization, a part of the unsaturated carboxylic acid anhydride is hydrolyzed to an unsaturated dicarboxylic acid, or one of the unsaturated dicarboxylic acids is esterified to obtain an unsaturated dicarboxylic acid. The acid value can be appropriately adjusted by the method of forming a half ester. Further, in order to finely finely disperse the layered compound in the aromatic vinyl-based resin, part or all of the aromatic vinyl-based resin may have a functional group having reactivity in addition to the acid group.

As a production method for introducing a further functional group having reactivity into the aromatic vinyl resin, a method of copolymerizing a vinyl monomer having a functional group or a chemical reaction of the aromatic vinyl resin is carried out. A method of modifying to give a functional group,
Etc. As the vinyl-based monomer having a functional group, various kinds can be used. For example, epoxy group-containing unsaturated compounds include glycidyl methacrylate and allyl glycidyl ether, and amino group-containing unsaturated compounds include acrylamine, aminoethyl methacrylate, aminopropyl methacrylate, aminostyrene, and the like. Examples of the unsaturated compound contained include 3-hydroxy-1-propene, 4-hydroxy-1-butene,
Cis-4-hydroxy-2-butene, trans-4-hydroxy-2-butene, 3-hydroxy-2-methyl-
1-Propene, 2-hydroxy-2-methyl-1-propene, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate and the like, and examples of the oxazoline group-containing unsaturated compound include vinyl oxazoline and the like. These may be used alone or in combination of two or more. As a method of modifying the aromatic vinyl resin by a chemical reaction to impart a functional group, a method of epoxidizing a double bond in a polymer chain with peracetic acid or the like to obtain an epoxy-modified aromatic vinyl resin, and the like can be mentioned. To be The method for producing the aromatic vinyl resin used in the present invention is not particularly limited, the monomer component is emulsion polymerization, which is a known polymerization method,
It can be obtained by polymerization by a method such as solution polymerization, suspension polymerization, bulk polymerization, bulk suspension polymerization and the like. The mixing ratio of the monomer components at this time is not particularly limited, and each component is appropriately mixed depending on the application.

The layered compounds used in the present invention include silicates, phosphates such as zirconium phosphate, titanates such as potassium titanate, tungstates such as sodium tungstate, and uranium such as sodium uranate. Acid salt,
One or more selected from the group consisting of vanadate salts such as potassium vanadate, molybdate salts such as magnesium molybdate, niobate salts such as potassium niobate, and graphite. A layered silicate is preferably used from the viewpoints of easy availability and handleability. The above-mentioned layered silicate is mainly composed of a tetrahedral sheet of silicon oxide and an octahedral sheet of metal hydroxide, and examples thereof include smectite group clay and swelling mica.

The above-mentioned smectite group clay is a natural or synthetic one represented by the following general formula (2). X ¹ _{0.2 to 0.6} Y ¹ _{2 to 3} Z ¹ ₄ O ₁₀ (OH) ₂ · nH ₂ O (2) (In the formula, X ¹ is K, Na, 1 / 2Ca, and 1 / 2Mg.
1 or more selected from the group consisting of, Y ¹ is Mg,
At least one selected from the group consisting of Fe, Mn, Ni, Zn, Li, Al, and Cr, and Z ¹ is Si and A
It is one or more selected from the group consisting of l. In addition, H ₂ O
Represents water molecules bound to interlayer ions, but n varies significantly depending on interlayer ions and relative humidity. ) Specific examples of the smectite group clay include, for example, montmorillonite, beidellite, nontronite, saponite, iron saponite, hectorite, sauconite, stevensite, bentonite, and the like, or substitution products, derivatives, or mixtures thereof. To be The bottom spacing of the smectite group clay in the initial aggregated state is about 1.0 to 1.7 nm, and the average particle size of the smectite group clay in the aggregated state is about 100 to 10,000.
It is 0 nm.

The swellable mica is a natural or synthetic one represented by the following general formula (3). X ² _{0.5 to 1.0} Y ^{2 2 to} ₃ (Z ² ₄ O ₁₀ ) (F, OH) ₂ (3) (wherein, X ² is a group consisting of Li, Na, K, Rb, Ca, Ba, and Sr. Y ² is at least one selected from the group consisting of Mg, Fe, Ni, Mn, Al, and Li, and Z ² is Si, Ge, Al,
One or more selected from the group consisting of Fe and B. ) These are substances having a property of swelling in water, a polar solvent compatible with water at an arbitrary ratio, and a mixed solvent of water and the polar solvent, and examples thereof include lithium-type teniolite, sodium-type teniolite, and lithium-type. Tetrasilicic mica, sodium tetrasilicic mica, etc., or their substitution products, derivatives, or mixtures thereof can be mentioned. The basal plane spacing of the swelling mica in the initial aggregation state is about 1.0 to 1.7 nm, and the average particle diameter of the swelling mica in the aggregation state is about 100 to 100,000 nm.

Some of the swelling mica described above has a structure similar to that of vermiculite, and such vermiculite equivalent products can be used. The vermiculite-equivalent products include a trioctahedral type and a dioctahedral type, and examples thereof include those represented by the following general formula (4). (Mg, Fe, Al) _{2 to 3} (Si _4-x Al _x ) O ₁₀ (OH) ₂ · (M ⁺ , M ²⁺ _1/2 ) _x · nH ₂ O (4) (where M is Exchangeable cations of alkali or alkaline earth metals such as Na and Mg, x = 0.6 to 0.9, n =
The bottom distance between the vermiculite-equivalent products in the initial aggregation state is about 1.0 to 1.7 nm, and the average particle size in the aggregation state is about 100 to 500,000 nm.
It is desirable that the crystal structure of the layered silicate has a high degree of purity in which the layers are regularly stacked in the c-axis direction, but a so-called mixed layer mineral in which the crystal cycle is disturbed and a plurality of kinds of crystal structures are mixed can be used. The layered silicate may be used alone or in combination of two or more kinds. Among these, montmorillonite, bentonite, hectorite and swellable mica with sodium ions between layers,
It is preferable from the viewpoint of dispersibility in the obtained aromatic vinyl-based resin composition and the effect of improving the physical properties of the aromatic vinyl-based resin composition.

The polyether structure-containing compound used in the present invention means a compound represented by the following general formula (1) having a hydrophilic group portion having a polyether structure in its molecule. ^{- (- R 1 -O-) n-} (1) ( wherein, R ¹ is either a divalent hydrocarbon group having 1 to 5 carbon atoms, be different even they are respectively the same R ¹ may contain a hydroxyl group, 2 ≦ n
≦ 1000. As the polyether structure, polyoxyethylene, polyoxyethylene-polyoxypropylene copolymer, polyoxypropylene, and the like are preferably used because they have high hydrophilicity and are easily manufactured.

Preferred examples of the polyether structure-containing compound include the following compounds: RO- (CH ₂ CH ₂ O) nR (5) RO- (CH ₂ CHCH ₃ O) nR (6) RO _{- (CH 2 CH 2 O)} m (CH 2 CHCH 3 O) nR (7) RCOO- (CH 2 CH 2 O) nOCOR (8) RCOOCH 2 CH (OH) CH 2 (OCH 2 CH (OH) CH 2 ) NOR (9)

[0018]

[Chemical 1]

[0019]

[Chemical 2]

(M and n are integers of 1 to 1000, R is hydrogen or a monovalent aliphatic, alicyclic or aromatic hydrocarbon group having 1 to 10 carbon atoms, and R ² is 1 to 10 carbon atoms. Other than these, divalent aliphatic or alicyclic hydrocarbon groups), polyoxyalkylene-modified polysiloxane compounds, and the like can also be used.

Furthermore, it is preferable that the polyether structure-containing compound is a compound which also has an aromatic hydrocarbon group in the molecule because the layered compound can be easily and finely dispersed. Here, the aromatic hydrocarbon group includes, for example, a phenyl group, a naphthyl group, an anthracenyl group, and a substituted aromatic hydrocarbon in which one or more hydrogens of these aromatic hydrocarbons are substituted with a hydrocarbon substituent. Groups and the like. Preferred examples of the polyether structure-containing compound which also has an aromatic hydrocarbon group in the molecule include the following compounds. _{R-Ph-O- (CH 2} CH 2 O) nR (12) RO- (CH 2 CH 2 O) m-Ph-O- (CH 2 CH 2 O) nR (13) RO- (CH 2 CHCH 3 O) m-Ph-O- ( CH 2 CHCH 3 O) nR (14) RO- (CH 2 CH 2 O) m-PhR 2 Ph-O- (CH 2 CH 2 O) nR (15) RO- ( _{CH 2 CHCH 3 O) m-} Ph-O- (CH 2 CHCH 3 O) nR (16) RO- (CH 2 CHCH 3 O) m-PhR 2 Ph-O- (CH 2 CHCH 3 O) nR (17 )

[0022]

[Chemical 3]

(M and n are integers of 1 to 1000, R is hydrogen or a monovalent aliphatic, alicyclic or aromatic hydrocarbon group having 1 to 10 carbon atoms, and R ² is 1 to 10 carbon atoms. Of the divalent aliphatic or alicyclic hydrocarbon group, and Ph is an aromatic hydrocarbon group.) Among the polyether structure-containing compounds, the compound as a whole shows hydrophilicity, which facilitates the clay treatment operation. Therefore, it is particularly preferable. The term "showing hydrophilicity" as used herein means that when 1 g of the compound is mixed in 100 g of water and stirred for 1 hour or more at 23 ° C., 80 ° C., or both, the following 1 to 3 are obtained. It is a compound in any of the above states. 1. Dissolves completely in water. 2. Emulsion stable in water and does not separate even if left standing for 1 hour or more.
3. Disperses uniformly in water and does not separate even if left standing for 1 hour or more.

The amount of the polyether structure-containing compound used is
It can be prepared so that the affinity between the layered compound and the aromatic vinyl resin and the dispersibility of the layered compound in the aromatic vinyl resin composition are sufficiently enhanced. If necessary, a plurality of polyether structure-containing compounds having different functional groups can be used in combination. Therefore, the amount of the polyether structure-containing compound used is not limited to any numerical value, but in general,
The lower limit of the compounding amount of the polyether structure-containing compound with respect to 100 parts by weight of the layered compound is 0.1 parts by weight, preferably 1.0 part by weight, more preferably 5.0 parts by weight, and further preferably Is 10.0 parts by weight, particularly preferably 15.0 parts by weight. The upper limit of the compounding amount of the polyether structure-containing compound with respect to 100 parts by weight of the layered compound is generally 200 parts by weight, preferably 1
The amount is 80 parts by weight, more preferably 160 parts by weight, still more preferably 140 parts by weight, and particularly preferably 120 parts by weight. When the lower limit of the compounding amount of the polyether structure-containing compound is less than 0.1 part by weight, the effect of finely dispersing the layered compound tends to be insufficient. Further, when the compounding amount of the polyether structure-containing compound exceeds 200 parts by weight, the fine dispersion effect does not change, while the polyether structure-containing compound provides the aromatic vinyl resin with excellent properties such as strength and heat resistance. It may damage, so 20
It is not necessary to use more than 0 parts by weight.

In the present invention, the method of treating the layered compound with the polyether structure-containing compound is not particularly limited, and for example, the method shown below can be used. First, the layered compound and the dispersion medium are mixed by stirring. The dispersion medium means water or a polar solvent containing water. The method of stirring the layered compound and the dispersion medium is not particularly limited, and, for example, a conventionally known wet stirrer is used. Examples of the wet agitator include a high-speed agitator that agitating blades rotate at a high speed to agitate, a wet mill that wet-mills a sample in a gap between a rotor and a stator that is subjected to a high shear rate, and a mechanical medium that uses a hard medium. Examples thereof include wet crushers, wet collision crushers that cause a sample to collide with a jet nozzle at a high speed, and wet ultrasonic crushers that use ultrasonic waves. When more efficient mixing is desired, the rotation speed of stirring is 1000 rpm or more, preferably 1500 rpm or more, more preferably 2000 rpm or more, or 500 (1 / s) or more, preferably 1000 (1 / s) or more, More preferably 1500
A shear rate of (1 / s) or more is applied. The upper limit of rotation speed is about 25,000 rpm, and the upper limit of shear rate is about 50 rpm.
It is 0000 (1 / s). Since there is a tendency that the value does not change even if stirring is performed at a value higher than the upper limit or shearing is applied, it is not necessary to perform stirring at a value higher than the upper limit. The time required for mixing is 1 to 10
Minutes, or more. Then, after adding the polyether structure-containing compound, stirring is further continued, and the mixture is thoroughly mixed. Then, it is dried and powdered if necessary.

In the aromatic vinyl resin composition of the present invention, the lower limit of the blending amount of the treated layered compound treated with the polyether structure-containing compound is typically 0 with respect to 100 parts by weight of the aromatic vinyl resin. It is 0.1 part by weight, preferably 0.3 part by weight, more preferably 0.5 part by weight, further preferably 1.0 part by weight, and particularly preferably 1.5 part by weight. The upper limit of the blending amount is typically 150 parts by weight, preferably 100 parts by weight, more preferably 70 parts by weight, further preferably 50 parts by weight, and particularly preferably 30 parts by weight. Is prepared. If the lower limit of the blending amount of the treated layered compound is less than 0.1 part by weight, the effect of improving mechanical properties and warpage may be insufficient, and if the upper limit exceeds 150 parts by weight, the surface appearance of the molded article may be reduced. Etc. may be damaged.

The structure of the layered compound dispersed in the aromatic vinyl resin composition of the present invention is such that the layer has the same structure as the layered compound before the treatment or before the addition to the aromatic vinyl resin. This is completely different from the multi-layered μm-sized aggregate structure. That is, the layers are cleaved by the treatment with the compound containing a polyether structure, and the layers are subdivided independently of each other. As a result, the layered compound was very finely dispersed in the aromatic vinyl-based resin composition in the form of thin plates independent of each other, and the number thereof was significantly larger than that of the layered compound before treatment or before being added to the aromatic vinyl-based resin. Increase. The dispersion state of such a thin plate-like layered compound can be expressed by the average layer thickness and the maximum layer thickness described below. If the average layer thickness is defined as the number average value of the layer thickness of the layered compound dispersed in the form of a thin plate, the upper limit of the average layer thickness of the layered compound in the aromatic vinyl resin composition of the present invention is 50 nm or less. , Preferably 45 nm or less, more preferably 40 nm or less. When the average layer thickness is larger than 50 nm, the effect of improving the mechanical properties of the aromatic vinyl resin composition of the present invention may not be sufficiently obtained. The lower limit of the average layer thickness is not particularly limited, but is preferably 0.5 nm or more, more preferably 0.7 nm or more, and further preferably 1.0 nm or more. Further, when the maximum layer thickness is defined as the maximum value of the layer thickness of the layered compound dispersed in the aromatic vinyl resin composition of the present invention in a thin plate shape, the upper limit of the maximum layer thickness of the layered compound is 200 nm or less. Is preferably 180 nm or less, and more preferably 150 nm or less. If the maximum layer thickness is larger than 200 nm, the balance of mechanical properties and surface appearance of the aromatic vinyl resin composition of the present invention may be impaired. The lower limit of the maximum layer thickness of the layered compound is not particularly limited, but is preferably 0.5 nm or more,
It is more preferably 1 nm or more, further preferably 2n.
It is m or more.

The layer thickness and layer length are the film obtained by heat-melting the aromatic vinyl resin composition of the present invention and then hot-press molding or stretch-molding, and the thin-wall film obtained by injection-molding a molten resin. The molded article and the like can be obtained from an image taken by using a microscope or the like. That is,
It is assumed that a film prepared by the above method or a thin flat plate injection-molded test piece having a wall thickness of about 0.5 to 2 mm is placed on the XY plane. From the above film or test piece, an ultrathin section having a thickness of about 50 μm to 100 μm is cut out on a plane parallel to the XZ plane or the YZ plane, and the section is cut to about 4 to 10 using a transmission electron microscope.
It can be obtained by observing at a high magnification of 10,000 times or more. The measurement, on the image of the transmission electron microscope obtained by the above method,
Select any region containing 100 or more layered compounds,
It can be quantified by making an image with an image processing device or the like and performing computer processing. Alternatively, it can be obtained by measuring using a ruler or the like.

The method for producing the aromatic vinyl-based resin composition of the present invention is not particularly limited, and for example, the aromatic vinyl-based resin and the treated layered compound treated with the polyether structure-containing compound can be variously treated. A method of melt kneading using a general kneader can be used. Examples of the kneader include a single-screw extruder, a twin-screw extruder, a roll, a Banbury mixer, a kneader, and the like, and a kneader having a high shear efficiency is particularly preferable. The aromatic vinyl-based resin and the layered compound treated with the polyether compound may be put into the above-mentioned kneading machine all at once and melt-kneaded, or the aromatic vinyl-based resin in a pre-melted state may be treated with the layered compound. You may add and melt-knead. In the aromatic vinyl resin composition of the present invention, if necessary, polybutadiene, acrylic rubber, ionomer, ethylene-propylene copolymer, ethylene-propylene-diene copolymer, natural rubber, chlorinated butyl rubber, α- A homopolymer of an olefin, a copolymer of two or more kinds of α-olefins (including any copolymer such as random, block, and graft, and a mixture thereof may be used), or an olefin elastomer such as an elastomer. Impact modifiers can be added. These may be modified with an acid compound such as maleic anhydride or an epoxy compound such as glycidyl methacrylate.

Any other thermoplastic resin or thermosetting resin, such as thermoplastic polyester resin, polyester carbonate resin, liquid crystal polyester resin, polyolefin resin, polyamide resin, etc., may be used as long as the mechanical properties and the like are not impaired. , A polyphenylene sulfide resin, a polyphenylene ether resin, a polyacetal resin, a polysulfone resin, and a polyarylate resin may be used alone or in combination of two or more. Further, additives such as pigments and dyes, heat stabilizers, antioxidants, ultraviolet absorbers, light stabilizers, lubricants, plasticizers, flame retardants, and antistatic agents can be added depending on the purpose. The aromatic vinyl resin composition obtained by the present invention can be molded by various molding processing methods such as injection molding, blow molding, extrusion molding, hot press molding, vacuum molding and the like. It can also be used for foam molding by using a foaming agent in combination. The obtained molded product has an excellent appearance and is excellent in mechanical properties, heat distortion resistance and the like, and therefore, it is suitably used for automobile parts, household electric appliance parts, household daily necessities, packaging materials and other general industrial materials.

[0031]

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these examples. The main raw materials used in Examples and Comparative Examples are summarized below.

(Raw material) -Aromatic vinyl resin 1: Produced according to Production Example 1,
Aromatic vinyl copolymer containing rubber-like polymer (acid value: 1
8) Aromatic vinyl-based resin 2: manufactured by Manufacturing Example 2
Styrene / acrylonitrile / methacrylic acid copolymer
(Acid value: 48) ・ Aromatic vinyl resin 3: A & M Styrene Co., Ltd.
Styrene methacrylic acid copolymer G9001 (acid value: 53) -Aromatic vinyl resin 4: Toyo Styrene Co., Ltd. general-purpose polystyrene G-13 (acid value: 0) -Layered compound: swelling mica (corp. Somasif ME100 of Chemical Co., Ltd., hereinafter referred to as ME100), and montmorillonite (Kunipia F of Kunimine Industries Co., Ltd., hereinafter referred to as Kunipia F) were used. -Polyether structure-containing compound 1: a compound in which ethylene oxide having an average repeating number of about 9 is bonded to both ends of bisphenol A (bisol 18E manufactured by Toho Chemical Co., Ltd.)
N). -Polyether structure-containing compound 2: Polyethylene glycol octyl phenyl ether (Nonion HS240 manufactured by NOF CORPORATION) having an average repeating number of ethylene glycol units of about 40. -Polyether structure-containing compound 3: number average molecular weight is 10
Polyethylene glycol of 00 (PEG of Sanyo Kasei Co., Ltd.
1000). Were used respectively.

(Measurement of dispersed state) Thickness 50 to 100 μm
Ultrathin sections were used. Transmission electron microscope (JEOL JE
M-1200EX), acceleration voltage 80kV and magnification 4
The state of dispersion of the layered compound was observed and photographed at a magnification of 10,000 to 1,000,000 times. In the TEM photograph, an arbitrary region in which 100 or more dispersed particles were present was selected, and the layer thickness was measured by manual measurement using a ruler with a scale or by processing using an image analyzer PIASIII of Interquest. .

(Bending Property) The aromatic vinyl resin composition of the present invention was dried (80 to 100 ° C., 3 hours). Using an injection molding machine with a mold clamping pressure of 75t, the resin temperature is 200 to 270 ° C.
Then, a test piece having dimensions of about 12.7 × 127 × 6.4 mm was injection molded. The flexural modulus of the obtained test piece was measured according to ASTM D-790.

(Production Example 1) In a reactor equipped with a stirrer and a reflux condenser, 250 parts of ion-exchanged water in a nitrogen stream, 0.4 part of sodium formaldehyde sulfoxylate,
Ferrous sulfate, 0.0025 part, 0.01 part of disodium ethylenediaminetetraacetate, and 2 parts of sodium dioctylsulfosuccinate were charged. After heating and stirring at 60 ° C, α-
75 parts of methyl styrene, 20 parts of acrylonitrile and 5 parts of methacrylic acid were continuously added dropwise over 6 hours together with cumene hydroperoxide as an initiator and t-dodecyl mercaptan as a polymerization degree modifier. After the dropwise addition was completed, the mixture was further stirred at 60 ° C. for 1 hour to terminate the polymerization and obtain a carboxylic acid-containing copolymer (A). On the other hand, in another reactor equipped with a stirrer and a reflux condenser, 250 parts of ion-exchanged water in a nitrogen stream, 0.5 part of potassium persulfate, and 10 parts of butadiene.
0 parts, t-dodecyl mercaptan 0.3 parts, and disproportionated sodium rosinate 3 parts were charged. Polymerization was carried out at a polymerization temperature of 60 ° C., and when the butadiene polymerization rate reached 80%, the polymerization was stopped to remove unreacted butadiene to obtain a polybutadiene latex. After adjusting the concentration of this latex by adding ion-exchanged water to 250 parts of water and 70 parts of polybutadiene, 0.4 part of sodium formaldehyde sulfoxylate and 0.002 of ferrous sulfate in a nitrogen stream were added.
5 parts and 0.01 parts of disodium ethylenediaminetetraacetate were added, and the mixture was heated with stirring at 60 ° C. and then methyl methacrylate 2 was added.
0 parts and 10 parts of styrene were continuously added dropwise over 5 hours together with cumene hydroperoxide as an initiator and t-dodecyl mercaptan as a polymerization degree adjusting agent. After the dropwise addition, stirring was further continued at 60 ° C. for 1 hour to terminate the polymerization, and a graft copolymer (B) was obtained. The carboxylic acid-containing copolymer (A) and the graft copolymer (B) latex are uniformly mixed at a ratio of 2: 1, a phenolic antioxidant is added, and the mixture is coagulated with an aqueous calcium chloride solution, followed by washing with water,
After dehydration and drying, a blend (C) of the carboxylic acid-containing copolymer (A) and the graft copolymer (B) was obtained.

(Production Example 2) In a reactor equipped with a stirrer and a reflux condenser, 250 parts of ion-exchanged water in a nitrogen stream, 0.4 part of sodium formaldehyde sulfoxylate,
Ferrous sulfate, 0.0025 part, 0.01 part of disodium ethylenediaminetetraacetate, and 2 parts of sodium dioctylsulfosuccinate were charged. After heating and stirring at 60 ° C., 72 parts of styrene, 20 parts of acrylonitrile, and 8 parts of methacrylic acid
Parts were continuously added dropwise over 6 hours together with cumene hydroperoxide as an initiator and t-dodecyl mercaptan as a polymerization degree adjusting agent. After the dropping was completed, stirring was further continued at 60 ° C. for 1 hour to complete the polymerization. This is coagulated with an aqueous solution of calcium chloride, washed with water, dehydrated and dried to give a methacrylic acid / styrene / acrylonitrile copolymer (D).
Got

(Production Example 3) Ion-exchanged water and a layered compound were mixed and stirred and kneaded for 15 minutes. The polyether structure containing compound was then added and processed by continuing mixing for 15 minutes. Then, it was dried and powdered using a spray dryer to obtain a polyether structure-containing compound-treated layered compound (clay A-1 to A-6). Table 1 shows the weight ratio of the raw materials used in the production examples.

[0038]

[Table 1]

(Examples 1 to 11 and Comparative Examples 1 to 6) The weight ratios shown in Tables 2 and 3 were based on 100 parts by weight of the resin, the treated layered compound obtained in Production Example 3, ME100, Kunipia F, and the resin. 0.2 parts by weight of phenolic stabilizer (Asahi Denka
ADEKA STAB AO-60 manufactured by Co., Ltd., using a twin-screw extruder (LABOTEX manufactured by Nippon Steel Co., Ltd.)
An aromatic vinyl resin composition was obtained by melt-kneading at 260 ° C. and evaluated. The melt-kneading temperature of each composition and the results are shown in Tables 2 and 3.

[0040]

[Table 2]

[0041]

[Table 3]

From Tables 2 and 3, when ME100 and Kunipia F were not treated with a polyether structure-containing compound, and when the acid value of the aromatic vinyl resin was less than 1, the dispersibility of the layered compound was poor and the bending property was poor. Was not improved. Therefore, Comparative Examples 1 to 6 did not have excellent balance.

[0043]

As described above in detail, by adding the treated layered compound treated with the polyether structure-containing compound in the aromatic vinyl resin, the layered compound is easily dispersed uniformly and finely and is bent. A resin composition having improved mechanical properties such as elastic modulus is provided. In the present invention, since mechanical properties can be improved without using a fibrous reinforcing agent such as glass fiber, it is possible to obtain a composition suitable for a recycling-oriented society such as excellent recyclability of resin, and industrially Very useful.

Claims (6)

[Claims] 1. An aromatic vinyl resin having an acid value in the range of 1 to 200 mgKOH / g, which is obtained by treating a layered compound with a polyether structure-containing compound represented by the following general formula (1): An aromatic vinyl resin composition obtained by adding a treated layered compound. ^{- (- R 1 -O-) n-} (1) ( wherein, R ¹ is either a divalent hydrocarbon group having 1 to 5 carbon atoms, be different even they are respectively the same Well, R ¹ may contain a hydroxyl group, 1 ≦ n
≦ 1000. ) 2. The aromatic vinyl resin composition according to claim 1, wherein the polyether structure-containing compound is a compound further having an aromatic hydrocarbon group in the molecule. 3. The layered compound is treated by mixing the polyether structure-containing compound and the layered compound in water or a polar solvent containing water to obtain a treated layered compound. The aromatic vinyl resin composition according to 1 or 2. 4. The average layer thickness of the layered compound in the resin composition is 5
It is 0 nm or less, The aromatic vinyl-type resin composition of any one of Claims 1-3 characterized by the above-mentioned. 5. The maximum layer thickness of the layered compound in the resin composition is 2
The aromatic vinyl resin composition according to any one of claims 1 to 4, which has a thickness of 00 nm or less. 6. The aromatic vinyl resin composition according to any one of claims 1 to 5, wherein the layered compound is a layered silicate.