JPH09176249A - Rubber-modified aromatic vinyl resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an ion-cross-linkable rubber-modified arom. vinyl resin compsn. excellent in moldability and resistances to impact and scratch. SOLUTION: This resin compsn. comprises an ion-cross-linkable arom. vinyl resin as a continuous phase and a rubberlike elastomer dispersed therein. The vinyl resin contains 2-20mol% at least one kind of structural unit derived from an α,β-ethylenically unsatd. carboxylic acid. In this compsn., the ratio of carboxyl groups neutralized by metal ions to all the carboxyl groups (i.e., the ionomerization ratio) of the above structural units is 10% or higher, the content of the α,β-ethylenically unsatd. carboxylic acid units (Amol%) and the ionomerization ratio (B%) satisfy the relation: 2<=(A+B)/100<=10, and the vinyl resin contains lower than 20wt.% high-molecular component contg. 0.5mol% or lower α,β-ethylenically unsatd. carboxylic acid units. The compsn. further contains 0.01-2 equivalents of a polycarboxylic acid component per equivalent of the metal ion used for neutralizing.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a rubber-modified aromatic vinyl resin composition having excellent impact resistance and scratch resistance. More specifically, a rubber-modified aromatic vinyl having ionic crosslinkability in the continuous phase by using a rubber-like elastic material as dispersed particles and containing a metal salt unit of α, β-ethylenically unsaturated carboxylic acid in the continuous phase. The present invention relates to a resin composition.

[0002]

2. Description of the Related Art In the fields of electric, electronic, OA, communication equipment, etc., various characteristics such as impact resistance, moldability, etc.
Rubber-modified styrene resins represented by HIPS resin and ABS resin are widely used. In recent years, from the viewpoint of recyclability of molding materials, there is a tendency to omit coating of the surface of molded articles, and correspondingly, there is a strong demand for improvement of surface characteristics such as scratch resistance. Therefore, methacrylic resins (polymethylmethacrylate, methylmethacrylate-styrene copolymer, etc.) are known as polymer materials with good scratch resistance currently on the market, and are used for home appliances, optical applications, miscellaneous goods, etc. Widely used in.

However, these materials need to contain a large amount of methyl methacrylate component in order to improve scratch resistance, resulting in high cost and inferior molding processability as compared with styrene resins. have. Further, a method of adding a lubricant such as silicon oil to improve the slipperiness of the surface is also used, but the improvement effect is poor. In the field of optical materials such as lenses, for example, divinylbenzene or diacrylate,
A method is known in which a bifunctional or polyfunctional vinyl monomer such as dimethacrylate is copolymerized with a styrene-based monomer to introduce a crosslinked structure by a covalent bond to improve scratch resistance. However, since a polymer material having covalent bond cross-linking cannot be melt-processed, it can be applied only when a plate obtained by cast polymerization is cut or used as it is.

As a means for solving such a problem, as a method for efficiently improving scratch resistance with a small amount of modification, there is a method of forming an ionic crosslinked body. Ion-crosslinking type material obtained by neutralizing the thermoplastic polymer material containing acidic functional groups such as carboxyl group and sulfo group by metal ion neutralizes the resin at high temperature unlike covalent bond crosslinking. At this time, the behavior of a thermoreversible gel, which allows free thermoforming due to loosening of cross-linking between molecules, improves heat resistance, scratch resistance, mechanical properties, etc., and adheres to metals, dissimilar polymer materials, etc. It is also known to improve the sex. Such an ion-crosslinking copolymer is industrialized with an ethylene resin such as an α-olefin polymer and is known as an ionomer.

Commercially available ethylene-based ionomers have a glass transition temperature below room temperature, which is much lower than the molding temperature in the amorphous phase, so that the mobility of polymer chains is extremely high in the thermoforming temperature range. And the ionic crosslinkability between the molecules is easily lowered, and good moldability can be obtained. On the other hand, in the case of an aromatic vinyl-based ionomer, the glass transition temperature of the amorphous phase is high and the temperature difference from the thermoforming temperature range is small, so a large amount of unsaturated metal salt component should be introduced. If so, the formability is significantly impaired. Further, if a large amount of a plasticizer is added to improve it, there is a problem that physical properties such as surface characteristics and tensile characteristics are deteriorated.

As a method for improving the moldability of such an aromatic vinyl ionomer, JP-A-47-28044 discloses an ionomer compound having a polar functional component and having a binding moment of 0.6 debye or more. Specific plasticizer, and in JP-A-51-36239, 0.6
It is disclosed that each of the selective plasticizers is a normally liquid, non-volatile compound having a functional group exhibiting a binding moment of Debye or higher and a solubility parameter of 9 or higher.

These are liquids in a normal state having a functional group having a binding moment of 0.6 Debye or more and having a solubility parameter of 9 or more as disclosed in JP-A-47-28044 and JP-A-51-36239. Specific and selective plasticizers such as non-volatile compounds, such as those having an alcoholic hydroxyl group such as glycerin, are effective for the polystyrene sulfonic acid ionomers described in the examples of the above publications. However, the carboxylic acid ionomer is not preferable because it causes an esterification reaction with the carboxylic acid during the melt-kneading at the time of addition and causes gelation.

When a monobasic acid such as stearic acid or polyethylene glycol is added as a plasticizer,
The effect of improving the scratch resistance during injection molding is offset.
In addition, most of the plasticizers shown here require a large amount to be added to improve the fluidity, and it is not limited to scratch resistance, but it can be improved by using other ionomers. It has a drawback that the physical properties such as the tensile strength are lowered and the effect of ionomerization is offset.

Further, JP-A-50-10344 discloses an impact-resistant styrene resin composition having improved heat resistance, which comprises a styrene-based ionic polymer and a rubber component dispersed in a particle form therein. Has been done. In this case, when a metal salt component of unsaturated acid is introduced into the polymer in an amount sufficient to improve scratch resistance, good moldability cannot be obtained. Further, when the metal ion forming the metal salt is only monovalent, the effect of improving the surface scratch resistance of the injection-molded product is low. Further, as a problem caused by the production method, there is a drawback that a large amount of a high-molecular component having a low unsaturated acid component content is mixed in the continuous phase, which results in a low effect of improving the surface scratch resistance.

[0010]

As described above, in the case of an aromatic vinyl ionomer, it is difficult to maintain the enhanced performance by ionic crosslinking and at the same time impart good moldability. It has long been desired to solve such problems. Therefore, in view of the present situation, the object of the present invention is to improve the scratch resistance and impact resistance of the surface of the molded article, and at the same time, to improve the molding processability of the ion-crosslinking rubber-modified aromatic vinyl resin composition. Is to provide.

[0011]

Means for Solving the Problems As a result of intensive studies to achieve the above object, the present inventors have found that α, β contained in an ion-crosslinking type aromatic vinyl resin forming a continuous phase. -By controlling the content of the ethylenically unsaturated carboxylic acid and the ionomerization rate in which the carboxyl group is neutralized by a metal ion under specific conditions, and further adding a polyvalent carboxylic acid component separately, particularly molding The present invention has led to the development of the rubber-modified aromatic vinyl-based resin composition of the present invention which has good scratch resistance on the product surface and good moldability.

That is, according to the present invention, in the ion-crosslinking rubber-modified aromatic vinyl-based resin containing a rubber-like elastic material as dispersed particles, (a) at least one ion-crosslinking aromatic-vinyl-based resin forming a continuous phase is used. 2-20 mol% of the above α, β-ethylenically unsaturated carboxylic acid is polymerized and contained,
Moreover, at least 10% or more of the carboxyl groups of the α, β-ethylenically unsaturated carboxylic acid are neutralized by metal ions, and the neutralized ratio (ionomerization ratio: B
%) And the polymerization content (A mol%) of the above α, β-ethylenically unsaturated carboxylic acid, the following relational expression: 2 ≦ (A ×
B) / 100 ≦ 10, and the polymer content of (b) and the resin that forms the continuous phase and has a polymerization content of α, β-ethylenically unsaturated carboxylic acid of 0.5 mol% or less. The amount is less than 20% by weight, and (c) the polyvalent carboxylic acid component is contained in a proportion of 0.01 to 2 equivalents relative to 1 equivalent of the metal ion used for neutralization. The present invention provides a rubber-modified aromatic vinyl resin composition.

The structure of the present invention will be described in detail below. In the present invention, examples of the aromatic vinyl-based monomer for forming the aromatic vinyl-based resin include styrene, α-methylstyrene, p-methylstyrene and the like, and these are used alone or in combination of two or more. be able to. Among these, styrene is particularly preferable. If desired, the aromatic vinyl monomer of the present invention may be used in combination with another vinyl compound capable of radical copolymerization. For example, one or more kinds of vinyl cyanide compounds such as acrylonitrile and methacrylonitrile for improving oil resistance, methyl methacrylate for improving weather resistance, and acrylates for adjusting glass transition temperature are used in combination. be able to.

In the present invention, what constitutes the α, β-ethylenically unsaturated carboxylic acid unit is a carboxylic acid capable of radical copolymerization with an aromatic vinyl monomer or the like,
Examples thereof include acrylic acid, methacrylic acid, itaconic acid, maleic acid, fumaric acid and the like. These may be used alone or in combination.

The rubber-like elastic material present as dispersed particles in the rubber-modified aromatic vinyl-based resin of the present invention may be any as long as it exhibits rubber-like properties at room temperature, and examples thereof include polybutadiene and styrene-butadiene copolymer. , Styrene-butadiene block copolymers, hydrogenated (partially hydrogenated) styrene-butadiene block copolymers, ethylene-propylene copolymers, ethylene-propylene-non-conjugated diene terpolymers, Examples thereof include isoprene polymers and styrene-isoprene copolymers.

The dispersed particle diameter of the rubber-like elastic material in the dispersed phase of the present invention is preferably in the range of 0.2 to 4 μm, and particularly 0.4 to 2 μm in order to increase the surface gloss. It is preferable. The dispersed particle size here is the number average particle size determined by image analysis of transmission electron micrographs. If the dispersed particle size is less than 0.2 micron, the effect as a reinforcing agent is poor. On the other hand, if the dispersed particle size exceeds 4 μm, the appearance of welds, flow marks, etc. is markedly deteriorated, which is not preferable.

In the present invention, the aromatic vinyl monomer unit constituting the aromatic vinyl resin forming the continuous phase is
98 to 80 mol%, and the content of α, β-ethylenically unsaturated carboxylic acid units is 2 to 20 mol%. Further, the content of the rubber-like elastic body forming the dispersed phase of the present invention is 2 to 20% by weight,
Preferably it is 3 to 15% by weight. When the amount of the rubber-like elastic body is less than 2% by weight, the effect as a strength reinforcing agent is poor. If the amount of the rubber-like elastic body exceeds 20% by weight,
It is not preferable because the rigidity decreases.

In the present invention, the proportion of ionized α, β-ethylenically unsaturated carboxylic acid units neutralized by metal ions (ionomerization rate) is at least 10% or more (that is, 10 to 100%), and the above α The polymerization content (mol%: A) of β-ethylenically unsaturated carboxylic acid and the ionomerization rate (%: B) must satisfy the following relationship. 2 ≦ (A × B) / 100 ≦ 10 The value of (A × B) / 100 calculated in the above relational expression needs to be in the range of 2 to 10, and more preferably 3 to 7. If this value is less than 2, the effect of improving the scratch resistance is low, and if it exceeds 10, the molding processability is significantly reduced.

In the resin forming the continuous phase, α, β-
The content of the polymer component having an ethylenically unsaturated carboxylic acid content of 0.5 mol% or less must be less than 20% by weight. If this content is 20% by weight or more, even if ionomerization is sufficiently performed, the scratch resistance of the molded product is insufficiently improved, which is not preferable. The amount of carboxylic acid that does not form a metal salt by neutralization in the polymer is preferably small from the viewpoint of moldability, and the amount of such α, β-ethylenically unsaturated carboxylic acid is preferably 0 to 10 mol%, It is preferably 0 to 5 mol%.

The metal as an ion source used for the neutralization of the present invention is not particularly limited, but preferably contains at least one or more divalent or higher valent metal, and the divalent or higher valent metal. Is an alkaline earth metal and / or a metal forming an amphoteric oxide. Specific metal elements include elements of Group II of the periodic table, such as zinc, cadmium, boron, aluminum, germanium, indium, silicon, tin, lead, antimony, and bismuth. These may be one type or two or more types. Of these, alkaline earth metals, zinc, and lead are preferable from the viewpoint of easiness of neutralization reaction, and particularly alkaline earth metals,
Zinc is the most preferred.

The polyvalent carboxylic acid added to the resin in the present invention is, for example, succinic acid, malic acid, adibic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, dodecane diacid, aconitic acid, citric acid. , Trimellitic acid, maleic acid, fumaric acid, citraconic acid, methylsuccinic acid, tetrahydrophthalic acid and the like, and their anhydrides can also be used. Of these, divalent carboxylic acids such as succinic acid, malic acid, and adibic acid are more preferable.

The amount of the polyvalent carboxylic acid added is 0.01 to 2 equivalents (equivalent = mol number × carboxylic acid) relative to 1 equivalent (equivalent = mol number × valence) of the metal ion used for neutralization. It is a base number), and more preferably 0.1 to 1 equivalent. If it is less than 0.01 equivalent, the effect of improving the moldability is not sufficient, and if it exceeds 2 equivalents, it causes new problems such as corrosion and coloring due to burning due to the effect of the polyvalent carboxylic acid remaining in the resin composition. . The polycarboxylic acid may be added at the same time as neutralizing the aromatic vinyl resin containing the rubber-like elastic material as dispersed particles, or after the completion of the neutralization reaction, a single-screw extruder or a twin-screw extruder. It can be added by a commonly used method such as a method of mixing by the like.

[0023]

Embodiments of the present invention will be described below. First, a rubber-modified aromatic vinyl-based resin containing a rubber-like elastic material as dispersed particles is subjected to suspension polymerization, bulk polymerization, solution polymerization or bulk-suspension in the presence or absence of a commonly used radical catalyst. It can be produced by a batch method, a continuous method, or a batch-continuous method by a method such as turbid polymerization. In particular, in order to obtain the rubber-modified aromatic vinyl resin of the present invention, the method used in the polymerization method of HIPS resin can be utilized.

That is, the rubber-like elastic material is dissolved in a raw material solution containing an aromatic vinyl monomer, an α, β-ethylenically unsaturated carboxylic acid monomer, a polymerization solvent if necessary, and a polymerization initiator,
The raw material solution is supplied to a reactor equipped with a stirrer to carry out polymerization. The polymerization temperature depends on the fluidity of the rubber-modified aromatic vinyl resin,
It can be determined in consideration of productivity, heat removal capacity of the reactor, and the like. The dispersed particle size can be determined by using a known technique such as control based on the rotation speed of stirring.

When the polymerization is carried out, α, β-ethylenically unsaturated carboxylic acid, α
Depending on the reactivity ratio of the β-ethylenically unsaturated carboxylic acid monomer, the characteristics of the reactor are taken into consideration as necessary, and the final polymerization rate is adjusted, and α, β-ethylenically unsaturated carboxylic acid monomer is appropriately added. Alternatively, take measures such as split addition. In particular, when the content of the polymer component having an α, β-ethylenically unsaturated carboxylic acid content of 0.5 mol% or less is 20% by weight or more, even if the ionomerization is sufficiently performed, the molded article is scratch-resistant. It is not preferable because the improvement of the property is insufficient. After the completion of the polymerization, the treatment is performed under vacuum in order to remove the unreacted monomer, the polymerization solvent and the like.

In the presence of a rubber-like substance, two or more components with an aromatic vinyl monomer are copolymerized to obtain a rubber-modified aromatic vinyl resin, and then α, β-ethylenically unsaturated The carboxylic acid component is L. Holliday "Io
nic Polymers "Applied Scie
nse Publishers LTD., London
n. Using the method introduced in detail in (1975) and the like, an ionomer is obtained by metal chloride by a neutralization reaction. Specifically, there may be mentioned a method of kneading the rubber-modified aromatic vinyl copolymer with a neutralizing agent such as an oxide or hydroxide of a divalent or higher metal as an ion source under melting.

The rubber-modified aromatic vinyl resin composition of the present invention thus obtained can be processed into an injection molding or an extruded sheet as it is, but if necessary, it may be an antioxidant, a heat stabilizer and a light stabilizer. Agent, flame retardant, nonionic surfactant, anionic surfactant, liquid paraffin as a lubricant, ethylenebis fatty acid amide, adipic acid, dibutyl or dioctyl ester of sebacic acid, organic polysiloxane, etc. Good. Further, if a small amount of higher fatty acids, metal salts of higher fatty acids and the like, which are usually used as lubricants, the scratch resistance is less likely to be reduced, and they can be used.

[0028]

Next, the present invention will be described in more detail by way of examples, which should not be construed as limiting the present invention. In addition, the physical-property test method in an Example is described below. (1) MFR: Based on ASTM D-1238. (2) Izod impact strength: According to ASTM-D256. (3) Pencil scratch value: In accordance with JIS-K5400.

(4) Content of α, β-ethylenically unsaturated carboxylic acid (mol%): The product is dissolved in dimethylformamide and reprecipitated in methanol. By this operation, the organic acid component not polymerized and contained in the resin is removed, and then the precipitate is filtered and dried. About 1 g of this sample was precisely weighed, dissolved in 100 ml of dimethylformamide, and neutralized and titrated with a 0.1N sodium hydroxide methanol solution to determine the concentration of carboxylic acid in the resin.

(5) Ionomerization rate (%): The product is dissolved in a mixed solvent of methyl ethyl ketone / acetic acid = 95/5 (wt / wt), and insoluble components are filtered. The filtrate is reprecipitated in methanol, the precipitate is filtered off and dried. By repeating this operation three times, the metal as the ion source in the composition is desorbed as the metal acetate salt. About 1 g of this sample was precisely weighed, dissolved in 100 ml of dimethylformamide, and neutralized and titrated with a 0.1N sodium hydroxide methanol solution to determine the concentration of carboxylic acid in the resin. The ionomerization rate was calculated from this measurement value and the measurement value of the α, β-ethylenically unsaturated carboxylic acid carboxylic acid content for the composition.

(6) Amount of polyvalent carboxylic acid component: The resin composition was dissolved in dimethylformamide, and the amount of polyvalent carboxylic acid component was measured by gas chromatography using cyclopentalol as an internal standard. (7) Low content of α, β-ethylenically unsaturated carboxylic acid component (% by weight): 10 mg of a sample after desorption of a metal as an ion source as a metal acetate by performing the same operation as the ionomerization rate / Ml dichloromethane solution. This solution was subjected to high performance liquid chromatography, and the column temperature: 40 ° C.
The amount of the α, β-ethylenically unsaturated carboxylic acid component of not more than mol% was measured.

Example 1 A raw material solution prepared by dissolving 5.8 parts by weight of polybutadiene as a rubber-like elastic material in a mixed solution of 73.6 parts by weight of styrene, 3.9 parts by weight of methacrylic acid and 16.7 parts by weight of ethylbenzene was added. -Butyl cumyl peroxide 0.02 part by weight was added and charged to a batch reactor equipped with a stirrer.
Polymerization was performed at 140 ° C for 3 hours at 140 ° C for 3 hours, and then the polymerization solution was transferred to an extruder with a biaxial vent, and at 230 ° C, 20 mm.
Under Hg conditions, the unreacted monomer and the polymerization solution were removed to obtain a rubber-modified styrene resin. The conversion rate of the monomer component by polymerization is 72%, and the methacrylic acid content is 8.4mo.
A rubber-modified styrenic resin having a polymer content of 1% and a methacrylic acid content of 0.5 mol% or less of 4.2% by weight was obtained.

With respect to 100 parts by weight of the obtained resin pellets, 1.66 parts by weight of zinc oxide, 0.5 parts by weight of zinc acetate,
After dry blending 2 parts by weight of malic acid, the mixture was kneaded with a twin-screw kneading extruder at a temperature of 260 ° C. and a feed rate of 15 kg / hr, and water was fed to the molten zone at a rate of 130 g / hr for neutralization. A plasticizer was kneaded together with the reaction to obtain a resin composition. Table 1 shows various analytical values related to the structure of the resin composition,
Table 2 shows mechanical properties. In Table 1, the content of the polyvalent carboxylic acid component is shown in equivalents to 1 equivalent of metal ion in the following Examples and Comparative Examples.

Example 2 A resin composition was prepared in the same manner as in Example 1 except that the polyvalent carboxylic acid component, malic acid, was changed to citric acid. Table 1 shows various analysis values relating to the structure of the resin composition, and Table 2 shows mechanical property values.

Example 3 Polymerization was carried out in the same manner as in Example 1, except that the rotation speed of stirring in the reactor was changed. Conversion rate of monomer by polymerization is 70%, rubber-modified styrenic resin containing 5% by weight of polymer component having methacrylic acid content of 8.5 mol% and methacrylic acid content of 0.5 mol% or less. was gotten. When the neutralization reaction was carried out by the method described in Example 1, 0.1 part by weight of polydimethylsiloxane was added at the same time to obtain a resin composition. Table 1 shows various analysis values relating to the structure of the resin composition, and Table 2 shows mechanical property values.

Example 4 Polymerization was carried out in Example 1 at 130 ° C. for 3 hours, 2 parts by weight of methacrylic acid was further added, and polymerization polymerization was carried out at 140 ° C. for 3 hours. The conversion rate of the monomer component by polymerization is 70
%, And a rubber-modified styrene-based resin having a methacrylic acid content of 11.5 mol% and a polymer component content of methacrylic acid content of 0.5 mol% or less of 0% by weight was obtained. A resin composition was prepared from the obtained resin pellets in the same manner as in Example 1. Table 1 shows various analysis values relating to the structure of the resin composition, and Table 2 shows mechanical property values.

Example 5 In Example 1, the composition of the raw material solution was changed to 5.8 parts by weight of polybutadiene, 75.9 parts by weight of styrene, 1.6 parts by weight of methacrylic acid and 16.7 parts by weight of ethylbenzene, and 130 ° C. After 3 hours, 1 part by weight of methacrylic acid was further added, and polymerization was carried out at 140 ° C. for 3 hours. The conversion rate of the monomer component by the polymerization was 73%, the methacrylic acid content was 5.1 mol%, and the methacrylic acid content was 0.
A rubber-modified styrenic resin containing 0% by weight of a polymer component of 5 mol% or less was obtained. A resin composition was prepared from the obtained resin pellets in the same manner as in Example 1. Table 1 shows various analysis values relating to the structure of the resin composition, and Table 2 shows mechanical property values.

Example 6 In Example 1, the additives added in the neutralization reaction were 1.17 parts by weight of zinc oxide, 0.5 parts by weight of zinc acetate, 1.0 part by weight of sodium hydrogen carbonate and 2 parts of malic acid. The resin composition was adjusted by changing to parts by weight. Table 1 shows various analysis values relating to the structure of the resin composition, and Table 2 shows mechanical property values.

Example 7 Polymerization was carried out in the same manner as in Example 1 except that the rotation speed of stirring in the reactor was changed. The conversion rate of the monomer component by polymerization is 75%,
Methacrylic acid content is 8.2 mol%, methacrylic acid content is 0.5 mol% or less, the content of polymer components is 10
A weight percent of rubber modified styrenic resin was obtained. To the obtained resin pellets, 0.1 part by weight of polydimethylsiloxane was added at the same time when the same neutralization reaction as in Example 1 was performed to obtain a resin composition. Table 1 shows various analysis values relating to the structure of the resin composition, and Table 2 shows mechanical property values.

Reference Example 1 With respect to the styrene / methacrylic acid copolymer not subjected to the neutralization reaction used in Example 1, Table 1 shows various analytical values relating to the structure of the resin composition, and Table 2 shows mechanical property values. Indicates.

Reference Example 2 With respect to the non-neutralized styrene / methacrylic acid copolymer used in Example 3, Table 1 shows various analytical values relating to the structure of the resin composition, and Table 2 shows mechanical property values. Indicates.

Reference Example 3 With respect to the styrene / methacrylic acid copolymer which is not subjected to the neutralization reaction used in Example 4, Table 1 shows various analytical values relating to the structure of the resin composition, and Table 2 shows mechanical property values. Indicates.

Reference Example 4 With respect to the non-neutralized styrene / methacrylic acid copolymer used in Example 4, Table 1 shows various analytical values relating to the structure of the resin composition, and Table 2 shows mechanical property values. Indicates.

Reference Example 5 Regarding rubber-modified styrenic resin (HIPS resin), high gloss HIPS resin (Estyrene H-78 manufactured by Nippon Steel Chemical Co., Ltd.) having excellent gloss is shown in Table 1 with respect to the structure of the resin composition. Table 2 shows various analysis values and mechanical property values.

Comparative Example 1 A resin composition was prepared in the same manner as in Example 1 except that the polycarboxylic acid component, malic acid, was not added. Table 1 shows various analysis values relating to the structure of the resin composition, and Table 2 shows mechanical property values.

Comparative Example 2 A resin composition was prepared in the same manner as in Example 1 except that the polyvalent carboxylic acid component, malic acid, was changed to the monovalent carboxylic acid, stearic acid. It was adjusted. Table 1 shows various analysis values relating to the structure of the resin composition, and Table 2 shows mechanical property values.

Comparative Example 3 A resin composition was prepared in the same manner as in Example 1, except that the addition amount of malic acid in Example 1 was changed to 0.01 parts by weight. Table 1 shows various analysis values relating to the structure of the resin composition, and Table 2 shows mechanical property values.

Comparative Example 4 A resin composition was prepared in the same manner as in Example 1 except that the amount of malic acid added in Example 1 was changed to 10 parts by weight. Table 1 shows various analysis values relating to the structure of the resin composition, and Table 2 shows mechanical property values.

Comparative Example 5 A resin composition was prepared in the same manner as in Example 1 except that the amount of zinc oxide added in Example 1 was changed to 0.4 part by weight. Table 1 shows various analysis values relating to the structure of the resin composition, and Table 2 shows mechanical property values.

Comparative Example 6 The composition of the raw material solution was 7.0 parts by weight of polybutadiene, 88.3 parts by weight of styrene, and 4.7 parts by weight of methacrylic acid, and t
-Add 0.02 parts by weight of butylcumyl peroxide,
After charging into a batch reactor equipped with a stirrer and polymerizing at 130 ° C. for 2 hours to form dispersed particles of the rubber component, water and a surfactant are charged into the reactor to carry out the subsequent reaction. 1 for suspension polymerization
After polymerizing at 40 ° C. for 3 hours and 150 ° C. for 2 hours, the obtained bead-like polymer is washed with water, charged into an extruder with a twin-screw vent, and subjected to unreacted simple reaction at 230 ° C. and 20 mmHg. The polymer was removed to obtain a rubber-modified styrene resin. The conversion rate of the monomer component by polymerization is 95%, the methacrylic acid content is 5.2 mol%, and the methacrylic acid content is 0.5 m.
A rubber-modified styrenic resin containing 30% by weight of a polymer component of ol% or less was obtained. The resin pellets thus obtained were treated in the same manner as in Example 1 to prepare a resin composition. Table 1 shows various analysis values relating to the structure of the resin composition, and Table 2 shows mechanical property values.

Comparative Example 7 A rubber-modified styrene resin was prepared in the same manner as in Comparative Example 6 except that the composition of the raw material solution was changed to 7.0 parts by weight of polybutadiene, 74.4 parts by weight of styrene, and 18.6 parts by weight of methacrylic acid. . The conversion rate of the monomer component by the polymerization is 95%, the content of the methacrylic acid content is 21.2 mol%, and the content of the polymer component having a methacrylic acid content of 0.5 mol% or less is 22% by weight. A resin was obtained. The resin pellets thus obtained were treated in the same manner as in Example 1 except that the amount of zinc oxide added during the neutralization reaction was 5 parts by weight to obtain a resin composition. Table 1 shows various analysis values relating to the structure of the resin composition, and Table 2 shows mechanical property values.

Comparative Example 8 Instead of zinc oxide and zinc acetate in Example 1,
The same treatment as in Example 1 was carried out except that 4 parts by weight of sodium hydrogen carbonate was used to obtain a resin composition. Table 1 shows various analysis values relating to the structure of the resin composition, and Table 2 shows mechanical property values.

[0053]

[Table 1]

[0054]

[Table 2]

[0055]

The aromatic vinyl resin composition of the present invention comprises
It is a material that is excellent in scratch resistance and livelihood workability, is hard to be scratched even without coating, and is a resin composition suitable as a material for injection molding applications in the fields of electricity, electronics, OA, communication equipment and the like. Excellent in scratch resistance and molding processability, electrical,
The present invention relates to a rubber-modified aromatic vinyl resin composition which is useful in applications such as electronics, OA and communication equipment.

Claims (4)

[Claims] 1. An ion-crosslinking rubber-modified aromatic vinyl-based resin containing a rubber-like elastic material as dispersed particles,
(A) The ion-crosslinking aromatic vinyl-based resin forming the continuous phase contains 2 to 20 mol% of at least one or more α, β-ethylenically unsaturated carboxylic acid polymerized, and the α, β-
At least 10% or more of the carboxyl groups of the ethylenically unsaturated carboxylic acid are neutralized by metal ions, and the neutralized ratio (ionomerization ratio: B%) and the above α,
Between the polymerization contents (A mol%) of β-ethylenically unsaturated carboxylic acid, the following relational expression: 2 ≦ (A × B) / 100 ≦
10), and the content of the polymer component having a polymerization content of 0.5 mol% or less of α, β-ethylenically unsaturated carboxylic acid in the resin forming the continuous phase (b) is 20% by weight. And less than (c) the polyvalent carboxylic acid component in a proportion of 0.01 to 2 equivalents with respect to 1 equivalent of the metal ion used for neutralization. Group vinyl resin composition. 2. The metal used for neutralization contains at least one or more divalent or higher valent metals, and the divalent or higher valent metals form an alkaline earth metal and / or an amphoteric oxide. The rubber-modified aromatic vinyl resin composition according to claim 1, which is a metal. 3. The rubber-modified aromatic vinyl-based thermoplastic resin composition according to claim 1, wherein the polyvalent carboxylic acid is a divalent carboxylic acid. 4. The content of the rubber-like elastic body is 2 to 20% by weight.
The rubber-modified aromatic vinyl resin composition according to claim 1, wherein the dispersed particle diameter is 0.2 to 4.0 microns.