KR101040827B1 - Low gloss graft copolymer, preparing method thereof and thermoplastic resin composition therefrom - Google Patents

Abstract

The present invention relates to a matte graft copolymer, a method for preparing the same, and a thermoplastic resin composition comprising the same, and more particularly, a hard polymer seed having a refractive index of 1.5 or more, and an alkyl having an average particle diameter of 0.6 to 10 μm surrounding the seed. By including an acrylate rubber polymer core, and a cross-linked graft shell surrounding the core, the matt effect due to light scattering on the surface of the copolymer is excellent, as well as excellent weather resistance and impact resistance when applied to a thermoplastic resin composition The present invention relates to a matte graft copolymer, a method for preparing the same, and a thermoplastic resin composition including the same, in which pigment colorability is greatly improved as compared with a matte graft copolymer resin composition of.

Matte graft copolymer, refractive index, alkylacrylate rubber, crosslinked graft shell, weather resistance, impact resistance, pigment coloring, thermoplastic resin

Description

Matte graft copolymer, a method for preparing the same, and a thermoplastic resin composition comprising the same {LOW GLOSS GRAFT COPOLYMER, PREPARING METHOD THEREOF AND THERMOPLASTIC RESIN COMPOSITION THEREFROM}

The present invention relates to a matte graft copolymer, a method for preparing the same, and a thermoplastic resin composition including the same, and more particularly, to a matt effect, and to excellent weather resistance and impact resistance when applied to a thermoplastic resin composition. The present invention relates to a matte graft copolymer, a method for preparing the same, and a thermoplastic resin composition including the same, compared with a conventional matte graft copolymer resin composition.

Generally, acrylonitrile-butadiene-styrene (ABS) resins prepared by graft copolymerization of styrene and acrylonitrile monomers on butadiene-based rubber polymers have impact resistance, processability, beautiful appearance, excellent mechanical strength, And it has high characteristics such as heat deformation temperature and is used for various applications such as automotive parts, electrical and electronic products, building materials.

However, ABS resin has an vulnerable effect because of the presence of ethylenically unsaturated polymer in butadiene rubber used as an impact modifier. There is a problem that it is not suitable for outdoor materials.

Therefore, acrylonitrile-styrene-acrylate, which uses acrylic rubber which does not have ethylenically unsaturated polymer instead of butadiene rubber as an impact modifier, in order to obtain a thermoplastic resin having excellent physical properties and excellent weatherability and aging resistance, ASA) terpolymer copolymer resin is used. Such ASA resins are used in various fields such as electronic and electric parts, construction materials, automobiles, ships, leisure goods, horticulture, etc. which are used outdoors. Among them, in the fields of automobile interior parts and building materials for homes, a matte material whose surface gloss is suppressed is demanded, and various studies on the production of matte resins have been conducted.

Conventional methods for producing a matte resin include embossing the surface of the resin or coating with a low gloss material. However, these methods increase the processing cost, there is a problem that the matte effect is reduced by the wear at the time of processing.

U. S. Patent No. 4,612, 347 discloses an acidic and basic graft copolymer, but the yield of condensation reaction is lowered and there is a problem of reproducibility. However, there is a problem that the gloss of the resin surface is not uniform. In addition, U.S. Patent No. 4,460,742 discloses a method using a matting agent, and Japanese Laid-Open Patent Publication No. 2005-343925 discloses a matt appearance molded article comprising a rubber polymer of 0.6 to 30 ㎛ or less, pigment coloring This is a bad problem.

In order to solve the problems of the prior art as described above, the present invention is excellent in the effect of the matt, excellent in weather resistance and impact resistance when applied to the thermoplastic resin composition as well as pigment colorability compared to the conventional matt graft copolymer resin composition It is an object of the present invention to provide this greatly improved matte graft copolymer, and a method for producing the same.

It is another object of the present invention to provide a thermoplastic resin composition containing the matt graft copolymer.

These and other objects of the present invention can be achieved by the present invention described below.

In order to achieve the above object, the present invention

(A) a hard polymer seed having a refractive index of 1.5 or more consisting of at least one compound selected from an aromatic vinyl compound, a vinyl cyan compound and an alkyl methacrylate compound;

(B) an alkyl acrylate rubber polymer core surrounding the seed and having an average particle diameter of 0.6 to 10 μm composed of an alkyl acrylate compound; And

(C) provides a matt graft copolymer surrounding the core, comprising a crosslinked graft shell composed of at least one compound selected from an aromatic vinyl compound, a vinyl cyan compound, and an alkyl methacrylate compound. .

Also,

(a) polymerizing 4 to 30 parts by weight of at least one monomer selected from an aromatic vinyl compound, a vinyl cyan compound and an alkyl methacrylate compound to prepare a hard polymer seed having a refractive index of 1.5 or more;

(b) polymerizing 20 to 80 parts by weight of an alkyl acrylate monomer to the prepared seed to prepare an alkyl acrylate rubber polymer core having an average particle diameter of 0.6 to 10 μm surrounding the seed; And

(c) cross-linking graft polymerization of 20 to 80 parts by weight of one or more monomers selected from aromatic vinyl compounds, vinyl cyan compounds and alkyl methacrylate compounds in the prepared cores to prepare a graft shell surrounding the core; It provides a method for producing a matte graft copolymer comprising.

In addition, the present invention is a thermoplastic comprising 5 to 60 parts by weight of the matte graft copolymer, 5 to 40 parts by weight of acrylate-styrene-acrylonitrile graft copolymer, and 35 to 75 parts by weight of styrene-acrylonitrile resin. It provides a resin composition.

Hereinafter, the present invention will be described in detail.

The matte graft copolymer of the present invention comprises a hard polymer seed having a refractive index of 1.5 or more, an alkylacrylate rubber polymer core having an average particle diameter of 0.6 to 10 μm surrounding the seed, and a crosslinked graft shell surrounding the core. , Excellent matt effect due to light scattering on the surface, it is characterized by excellent pigment colorability by using a hard polymer seed having a refractive index similar to the matrix.

The matte graft copolymer

(A) a hard polymer seed having a refractive index of 1.5 or more consisting of at least one compound selected from an aromatic vinyl compound, a vinyl cyan compound and an alkyl methacrylate compound;

(B) an alkyl acrylate rubber polymer core surrounding the seed and having an average particle diameter of 0.6 to 10 μm composed of an alkyl acrylate compound; And

(C) It comprises a cross-linked graft shell surrounding the core and consisting of at least one compound selected from aromatic vinyl compounds, vinyl cyan compounds and alkyl methacrylate compounds.

The hard polymer seed preferably has a refractive index of 1.5 or more. When the refractive index is 1.5 or more, the refractive index is similar to that of the styrene-acrylonitrile resin used as the matrix, thereby improving the colorability.

The alkyl acrylate rubber polymer core is preferably an average particle diameter of 0.6 to 10 ㎛. In the case of the average particle diameter, the matt effect is excellent while the stability is not lowered.

The shell is preferably a crosslinked graft shell. In the case of the crosslinked graft shell, light scattering occurs on the surface of the copolymer, thereby providing an excellent matt effect.

In the method for preparing a matte graft copolymer of the present invention, a hard polymer seed having a refractive index of 1.5 or more is prepared, and an alkyl acrylate rubber polymer core having a diameter of 0.6 to 10 μm surrounding the seed is prepared. Preparing a shell.

The manufacturing method of the matte graft copolymer

(a) 4 to 30 parts by weight of at least one monomer selected from an aromatic vinyl compound, a vinyl cyan compound and an alkyl methacrylate compound, up to 1 part by weight of an electrolyte, 0.01 to 3 parts by weight of a crosslinking agent, 0.01 to 3 parts by weight of a grafting agent, Preparing a hard polymer seed having a refractive index of 1.5 or more by polymerizing 0.01 to 3 parts by weight of a polymerization initiator and 0.01 to 5 parts by weight of an emulsifier;

(b) 20 to 80 parts by weight of alkylacrylate monomer, 0.01 to 3 parts by weight of crosslinking agent, 0.01 to 3 parts by weight of grafting agent, 0.01 to 3 parts by weight of polymerization initiator, 0.01 to 5 parts by weight of emulsifier, and stabilizer Polymerizing 5 parts by weight to prepare an alkylacrylate rubber polymer core having an average particle diameter of 0.6 to 10 μm surrounding the seed; And

(c) 20 to 80 parts by weight of at least one monomer selected from an aromatic vinyl compound, a vinyl cyan compound and an alkyl methacrylate compound, 0.01 to 3 parts by weight of a crosslinking agent, 0.01 to 3 parts by weight of a grafting agent, and polymerization to the prepared core. And 0.01 to 3 parts by weight of an initiator, 0.01 to 5 parts by weight of an emulsifier, and up to 5 parts by weight of a stabilizer to prepare a graft shell surrounding the core.

As the aromatic vinyl compound, styrene or a derivative thereof is preferably used. Specifically, styrene, α-methylstyrene, p-methylstyrene, vinyltoluene, or the like may be used alone or in combination of two or more thereof.

As the vinyl cyan compound, acrylonitrile, methacrylonitrile, ethacrylonitrile, or the like may be used alone or in combination of two or more thereof.

The alkyl methacrylate compound may be used by mixing two or more of those having 1 to 4 carbon atoms in the alkyl moiety, and preferably methyl methacrylate or ethyl methacrylate having 1 to 2 carbon atoms in the alkyl moiety. To use.

As said alkyl acrylate compound, the C2-C8 thing of an alkyl part can be used individually or in mixture of 2 or more types, Preferably it is C4-C8 of an alkyl part, More preferably, it is butyl acrylate, Ethyl acrylate or ethyl hexyl acrylate is used.

As the electrolyte, KCl, NaCl, KHCO ₃ , NaHCO ₃ , K ₂ CO ₃ , Na ₂ CO ₃ , KHSO ₃ , NaHSO ₃ , Na ₂ S ₂ O ₇ , K ₄ P ₂ O ₇ , K ₃ PO ₄ , Na ₃ PO ₄ , K ₂ HPO _4, or Na ₂ HPO ₄ may be used alone or in combination of two or more thereof.

As the crosslinking agent, ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate, 1,3-butanediol dimethacrylate, 1,6-hexanediol dimethacrylate, neopentyl Preference is given to using glycol dimethacrylate, trimethylol propane trimethacrylate or trimethylol methane triacrylate and the like.

As the grafting agent, it is preferable to use allyl methacrylate (AMA), triallyl isocyanurate (TAIC), triallyl amine (TAA) or diallyl amine (DAA).

The polymerization initiator is a water-soluble initiator such as sodium persulfate, potassium persulfate, ammonium persulfate, cumene hydroperoxide, diisopropyl benzene hydroperoxide, azobisisobutylnitrile, tertiary butyl hydroperoxide, paramethane hydride Oil-soluble initiators, such as a loperoxide and benzoyl peroxide, or the redox type polymerization initiator which combined the oxidation-reduction agent, etc. can be used.

An activator may be used to promote the initiation reaction of the peroxide together with the polymerization initiator, and the activator may be sodium formaldehyde sulfoxylate, sodium ethylenediamine tetraacetate, ferrous sulfate, dextrose, sodium pyrrolate or It is preferable to use sodium sulfite etc. individually or in mixture of 2 or more types.

The type of the emulsifier is not particularly limited, and derivatives of alkyl sulfo succinate metal salts, derivatives of alkyl sulfate esters or sulfonic acid metal salts, fatty acid soaps or rosin acid soaps may be used.

The stabilizer may be polyvinyl alcohol (PVA), polyacrylic acid (PAA), hydroxypropyl cellulose (HPC) or polyvinylpyrrolidone (PVP). When the stabilizer is an average particle diameter of the rubber polymer core, or when the average particle diameter of the matte graft copolymer is more than 0.9 ㎛, for the stability of these latex to 100 parts by weight of the total monomer used in the production of the matte graft copolymer It is preferable to use it at 5 parts by weight.

In addition to the above components, mercaptans molecular weight modifiers may be further used in the preparation of the seed, core and shell of the matte graft copolymer.

In the step of preparing the hard polymer seed and the rubber polymer core, the batch and continuous dosing methods may be used alone, or the two methods may be used as the monomers.

The elastomeric core may increase the size of the particles by single or multistage seed polymerization, or core polymerization.

In the step of preparing the cross-linked graft shell, the grafting reaction is difficult due to the rapid increase of the pH of the polymerization system when the monomer is added in a batch, and the stability of the particles of the shell is lowered so that the internal structure of the particles is not uniform. Preference is given to using the method.

Matte graft copolymer prepared by the above method is in a latex state, it can be prepared in powder form by agglomeration with a coagulant, and then aged, dehydrated, and dried, or dried by a spray dryer.

As the flocculant, an aqueous solution of an inorganic salt such as aluminum chloride, sodium sulfate, sodium nitrate, calcium chloride, magnesium sulfate, aluminum sulfate, or an aqueous solution of a flocculant such as sulfuric acid or hydrochloric acid may be used.

The thermoplastic resin composition of the present invention is 5 to 60 parts by weight of the powdery matte graft copolymer, 5 to 40 parts by weight of acrylate-styrene-acrylonitrile graft (ASA) copolymer, and styrene-acryl as a hard matrix. 35 to 75 parts by weight of ronitrile (SAN) resin.

The acrylate-styrene-acrylonitrile graft copolymer has a core-shell structure and is a graft copolymer capable of melt kneading with a styrene-acrylonitrile resin, which is a hard matrix, and has an average particle diameter of 0.1 to 0.6 µm. Is preferably.

The styrene-acrylonitrile resin is composed of a hard polymer-forming monomer having a glass transition temperature of at least 60 ° C. or higher, and may form a polycarbonate polymer, a compound including a unit derived from an aromatic vinyl compound, a vinyl cyan compound, and methyl methacrylate. It is preferable to produce a compound or the like that can be used alone or in combination of two or more thereof.

The thermoplastic resin composition may further include additives such as dyes, pigments, lubricants, antioxidants, ultraviolet stabilizers, heat stabilizers, reinforcing agents, fillers, flame retardants, foaming agents, plasticizers, or matting agents, which are commonly used according to uses.

Hereinafter, preferred examples are provided to help the understanding of the present invention, but the following examples are merely for exemplifying the present invention, and various changes and modifications within the scope and spirit of the present invention are apparent to those skilled in the art. It is natural that such variations and modifications fall within the scope of the appended claims.

[Example]

<Production of High Color Matte Graft Copolymer>

Example 1

Hard Polymer Seed Manufacturing Step

40 parts by weight of distilled water was added to a nitrogen-substituted polymerization reactor, and the temperature was raised to 75 ° C. Then, 0.025 parts by weight of potassium persulfate was added to initiate the reaction, and 5 parts by weight of styrene, 0.05 parts by weight of Na ₂ CO ₃ , and ethylene glycol dimetha A mixture of 0.025 parts by weight of acrylate, 0.025 parts by weight of allyl methacrylate and 0.05 parts by weight of sodium lauryl sulfate was continuously added at 75 ° C. to prepare a hard polymer seed having an average particle diameter of 0.35 μm and a refractive index of 1.5 or more.

Rubber polymer core manufacturing step

In the presence of the prepared hard polymer seed latex, 60 parts by weight of distilled water, 55 parts by weight of butyl acrylate, 0.3 parts by weight of ethylene glycol dimethacrylate, 0.3 parts by weight of allyl methacrylate, 0.5 parts by weight of cumene hydroperoxide and A mixture of 0.5 parts by weight of sodium lauryl sulfate was continuously added at 75 ° C. to prepare a rubber polymer core having an average particle diameter of 0.8 μm.

Step of manufacturing crosslinked graft shell

In the presence of the prepared rubber polymer core, 50 parts by weight of distilled water, 30 parts by weight of styrene, 10 parts by weight of acrylonitrile, 0.2 parts by weight of ethylene glycol dimethacrylate, 0.2 parts by weight of allyl methacrylate, cumene hydroperoxide 0.5 The polymerization reaction was carried out while continuously feeding the mixture which mixed a weight part and 0.65 weight part of sodium lauryl sulfates at 75 degreeC. In addition, in order to increase the polymerization conversion rate after the addition of the mixture is completed and further reacted at 75 ℃ for 1 hour and cooled to 60 ℃ to terminate the polymerization reaction to prepare a matt graft copolymer latex. The polymerization conversion rate of the prepared matt graft copolymer latex was 98%, solid content was 40%.

Manufacture of High Color Matte Graft Copolymer Powder

After the matt graft copolymer latex prepared above was subjected to atmospheric coagulation at 80 ° C. using an aqueous calcium chloride solution, aged at 95 ° C., dehydrated and washed, and dried for 30 minutes with 90 ° C. hot air. Was prepared.

Example 2

In preparing the hard polymer seed in Example 1 was carried out in the same manner as in Example 1 except that 3.5 parts by weight of styrene and 1.5 parts by weight of methyl methacrylate was used instead of 5 parts by weight of styrene.

Example 3

After preparing the rubber polymer core in Example 1, 80 parts by weight of distilled water, 50 parts by weight of butyl acrylate, 0.3 parts by weight of ethylene glycol dimethacrylate, allyl methacrylate in the presence of 10 parts by weight of the prepared 0.8 ㎛ size core A mixture of 0.3 part by weight, 0.5 part by weight of cumene hydroperoxide, 0.5 part by weight of sodium lauryl sulfate and 0.03 part by weight of polyvinyl alcohol was continuously added at 75 ° C. to prepare a rubber polymer core having an average particle diameter of 1.35 μm.

Except for using 0.8 parts by weight of sodium lauryl sulfate and 0.05 parts by weight of polyvinyl alcohol when preparing the cross-linked graft shell in the presence of the copolymer polymer core was carried out in the same manner as in Example 1.

Comparative Example 1

Except that 5 parts by weight of butyl acrylate was used in place of 5 parts by weight of styrene when preparing a hard polymer seed in the same manner as in Example 1.

Comparative Example 2

Except for producing a polymer seed having a hard particle seed in Example 1 using 0.3 parts by weight of sodium lauryl sulfate, 0.15 μm, and using this to prepare a rubber polymer core having an average particle diameter of 0.35 μm Was carried out in the same way.

<Production of the thermoplastic resin composition>

Example 4

30 parts by weight of the matte graft copolymer powder prepared in Example 1, 11 parts by weight of the acrylate-styrene-acrylonitrile graft copolymer SA927 (manufactured by LG Chemical) and a styrene-acrylonitrile copolymer 81HF with a hard matrix. (Manufactured by LG Chemical) 1 part by weight of lubricant, 0.5 part by weight of antioxidant, 0.5 part by weight of UV stabilizer, 1 part by weight of carbon black, and 3 parts by weight of matte agent were added and mixed. This was prepared in pellet form using a 40 pie extrusion kneader at a cylinder temperature of 220 ° C., and injected into the pellet to prepare a physical specimen.

Example 5

Except for using the matte graft copolymer powder prepared in Example 2 as the matte graft copolymer powder in Example 4 was carried out in the same manner as in Example 4.

Example 6

The same procedure as in Example 4 was performed except that the matte graft copolymer powder prepared in Example 3 was used as the matte graft copolymer powder in Example 4.

Example 7

20 parts by weight of the matte graft copolymer powder, 22 parts by weight of the acrylate-styrene-acrylonitrile graft copolymer (SA927, manufactured by LG Chemical) and a styrene-acrylonitrile copolymer (81HF) in a hard matrix , LG Chem) was carried out in the same manner as in Example 6, except that 58 parts by weight was used.

Comparative Example 3

The same procedure as in Example 4 was performed except that the matte graft copolymer powder prepared in Comparative Example 1 was used as the matte graft copolymer powder in Example 4.

Comparative example  4

The same procedure as in Example 4 was performed except that the matte graft copolymer powder prepared in Comparative Example 2 was used as the matte graft copolymer powder in Example 4.

Comparative Example 5

3 parts by weight of the matte graft copolymer powder, 41 parts by weight of the acrylate-styrene-acrylonitrile graft copolymer (SA927, manufactured by LG Chemical) and a styrene-acrylonitrile copolymer (81HF) in a hard matrix , LG Chem) was carried out in the same manner as in Example 4, except that 56 parts by weight was used.

[Test Example]

The physical properties of the thermoplastic resin compositions prepared in Examples 4 to 7, and Comparative Examples 3 to 5 were measured by the following method, and the results are shown in Table 1 below.

* Glossiness (75 °)-measured according to ASTM D528.

* Pigment coloring-L value of the coloring test piece was measured using a color difference meter. The lower the L value, the lower the brightness, resulting in a darker black color, indicating excellent pigment colorability.

* Izod impact strength (1/4 notched at 23 ° C., kg · cm / cm)-measured in accordance with ASTM D256.

division Example 4 Example 5 Example 6 Example 7 Comparative Example 3 Comparative Example 4 Comparative Example 5 Glossiness 20.1 19.6 15.4 17.8 19.8 58 64 Pigment coloring 28.3 27.4 29.0 28.5 32.8 28.1 28.8 Impact strength
(Kgcm / cm) 13.5 13.1 11.2 13.0 11.1 8.8 15.0

As shown in Table 1, according to the present invention, an embodiment including a hard polymer seed having a refractive index of 1.5 or more, a rubber polymer core having an average particle diameter of 0.6 to 10 μm surrounding the seed, and a crosslinked graft shell surrounding the core It was confirmed that the thermoplastic resin compositions of Examples 4 to 7 using the matte graft copolymers of 1 to 3 not only had excellent matting properties, but also had excellent impact resistance and improved pigment colorability.

On the other hand, Comparative Example 3 using the matte graft copolymer of Comparative Example 1 containing a seed having a refractive index of less than 1.5 was reduced in pigment colorability, the size of the average particle diameter comprises a rubber polymer core does not fall within the scope of the present invention Comparative Example 4 using the matte graft copolymer of Comparative Example 2 was not sufficiently expressed in the matt effect, even in the case of Comparative Example 5 using the matte graft copolymer in a trace amount that does not fall within the scope of the present invention It was confirmed that the effect was not sufficiently expressed.

As described above, according to the present invention, the matte effect due to light scattering is excellent on the surface of the copolymer, and when applied to a thermoplastic resin composition, it is excellent in weatherability and impact resistance as well as a conventional matte graft copolymer resin composition. In comparison, there is an effect of providing a matte graft copolymer with improved pigment colorability and a thermoplastic resin composition comprising the same.

Claims (14)

(a) a hard polymer seed having a refractive index of 1.5 or more composed of at least one compound selected from an aromatic vinyl compound, a vinyl cyan compound and an alkyl methacrylate compound; (b) an alkyl acrylate rubber polymer core surrounding the seed and having an average particle diameter of 1.35 to 10 μm consisting of an alkyl acrylate compound; And (c) surrounding the core, comprising a crosslinked graft shell composed of at least one compound selected from an aromatic vinyl compound, a vinyl cyan compound and an alkyl methacrylate compound. Matte Graft Copolymer. The method of claim 1, The aromatic vinyl compound is at least one selected from the group consisting of styrene, α-methylstyrene, p-methylstyrene and vinyltoluene, The vinyl cyan compound is at least one selected from the group consisting of acrylonitrile, methacrylonitrile and ethacrylonitrile, The alkyl methacrylate compound is selected from the group consisting of methyl methacrylate and ethyl methacrylate, characterized in that at least one Matte Graft Copolymer. The method of claim 1, The alkyl acrylate compound is at least one member selected from the group consisting of butyl acrylate, ethyl acrylate and ethylhexyl acrylate. Matte Graft Copolymer. delete (a) 4 to 30 parts by weight of at least one monomer selected from an aromatic vinyl compound, a vinyl cyan compound and an alkyl methacrylate compound, up to 1 part by weight of an electrolyte, 0.01 to 3 parts by weight of a crosslinking agent, 0.01 to 3 parts by weight of a grafting agent, Preparing a hard polymer seed having a refractive index of 1.5 or more by polymerizing 0.01 to 3 parts by weight of a polymerization initiator and 0.01 to 5 parts by weight of an emulsifier; (b) 20 to 80 parts by weight of alkylacrylate monomer, 0.01 to 3 parts by weight of crosslinking agent, 0.01 to 3 parts by weight of grafting agent, 0.01 to 3 parts by weight of polymerization initiator, 0.01 to 5 parts by weight of emulsifier, and stabilizer Polymerizing at most 5 parts by weight to prepare an alkylacrylate rubber polymer core having an average particle diameter of 0.6 to 10 μm surrounding the seed; And (c) 20 to 80 parts by weight of at least one monomer selected from an aromatic vinyl compound, a vinyl cyan compound and an alkyl methacrylate compound, 0.01 to 3 parts by weight of a crosslinking agent, 0.01 to 3 parts by weight of a grafting agent, and a polymerization initiator in the prepared core. 0.01 to 3 parts by weight, emulsifier 0.01 to 5 parts by weight, and up to 5 parts by weight of a stabilizer to cross-link graft polymerization to produce a graft shell surrounding the core. Method for preparing a matt graft copolymer. The method of claim 5, The said aromatic vinyl compound is 1 or more types chosen from the group which consists of styrene, (alpha) -methylstyrene, p-methylstyrene, and vinyltoluene, The vinyl cyan compound is one or more selected from the group consisting of acrylonitrile, methacrylonitrile and ethacrylonitrile, The alkyl methacrylate compound is at least one member selected from the group consisting of methyl methacrylate and ethyl methacrylate. Method for preparing a matt graft copolymer. The method of claim 5, The alkyl acrylate compound is at least one member selected from the group consisting of butyl acrylate, ethyl acrylate and ethylhexyl acrylate. Method for preparing a matt graft copolymer. The method of claim 5, The crosslinking agent is ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate, 1,3-butanediol dimethacrylate, 1,6-hexanediol dimethacrylate, neopentyl At least one member selected from the group consisting of glycol dimethacrylate, trimethylol propane trimethacrylate, and trimethylol methane triacrylate. Method for preparing a matt graft copolymer. The method of claim 5, The grafting agent is at least one member selected from the group consisting of allyl methacrylate, triallyl isocyanurate, triallyl amine and diallyl amine. Method for preparing a matt graft copolymer. The method of claim 5, The stabilizer is at least one member selected from the group consisting of polyvinyl alcohol, polyacrylic acid, hydroxypropyl cellulose and polyvinylpyrrolidone. Method for preparing a matt graft copolymer. The method of claim 10, The amount of the stabilizer is characterized in that up to 5 parts by weight based on 100 parts by weight of the total monomers used to prepare the matt graft copolymer. Method for preparing a matt graft copolymer. The method of claim 5, Step (a) or (b) is characterized in that using a single or multi-step polymerization method Method for preparing a matt graft copolymer. 5 to 60 parts by weight of the matte graft copolymer according to claim 1, 5 to 40 parts by weight of acrylonitrile-styrene-acrylate graft copolymer, and 35 to 75 parts by weight of styrene-acrylonitrile resin. Characterized Thermoplastic resin composition. The method of claim 13, The styrene-acrylonitrile resin, characterized in that consisting of a hard polymer-forming monomer having a glass transition temperature of at least 60 ℃. Thermoplastic resin composition.