KR20190083540A - A method for manufacturing acrylic graft copolymer having improved impact strength and surface appearance - Google Patents

Abstract

The present invention is to provide a method for manufacturing an acrylic graft copolymer comprising the following steps: (a) reacting a rubber modified graft copolymer, an acrylic monomer, a first initiator, a cross-linking agent and an emulsifier and preparing a structure including a layer consisting of acrylic rubber on the surface of the rubber modified graft copolymer; and (b) grafting a copolymer made of an aromatic vinyl monomer and an unsaturated nitrile monomer to the structure in the presence of a mercaptan molecular weight modifier and a second initiator. The second initiator is a peroxycarbonate compound. The input amount of the mercaptan molecular weight modifier is 0.1-0.5 parts by weight with respect to 100 parts by weight of the copolymer made of the aromatic vinyl monomer and the unsaturated nitrile monomer.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to an acryl-based graft copolymer having excellent impact resistance and appearance,

The present invention relates to an acrylic graft copolymer and a process for producing the acrylic graft copolymer. More particularly, the present invention relates to a process for producing an acrylic graft copolymer excellent in impact resistance and appearance.

Generally, ABS resin obtained by graft copolymerizing styrene and acrylonitrile monomer to a butadiene rubber-like polymer has excellent impact resistance and processability, excellent mechanical strength and heat distortion temperature, and excellent coloring property, Devices and the like.

However, since ABS resin contains chemically unstable double bonds in the rubber component used, there is a problem that the rubber component is easily aged by the ultraviolet rays and is very vulnerable to weatherability.

On the other hand, a method using a chemically stable acrylic rubber instead of the butadiene rubber, a method using a rubbery polymer obtained by polymerizing butadiene and an acrylic polymerizable monomer, and the like have been used.

Particularly, an ASA (acrylate-styrene-acrylonitrile) graft copolymer resin in which styrene and acrylonitrile monomer are graft-copolymerized with an acrylic rubber-like polymer is used for interior and exterior parts such as automobiles and agricultural equipments, It is widely used for electric and electronic goods.

Since the ASA resin does not have a chemically unstable double bond, a special effect can be obtained in weatherability, but there is a problem that the impact resistance and the coloring property are low as compared with the ABS resin.

On the contrary, a method of increasing the particle diameter of the acrylic rubber or lowering the gel content of the rubbery polymer has been suggested. However, these methods are not only difficult to control the physical properties of the graft copolymer, have. Further, in order to improve the impact resistance, attempts have been made to improve the physical properties such as impact resistance and gloss by preparing and mixing acrylic rubbers having different particle diameters, respectively, but have failed to obtain sufficiently satisfactory results.

In addition, the thermoplastic ASA resin containing these ASA resins has excellent mechanical properties but may have a limited application due to low gloss and flowability.

 Therefore, there is a need to develop a technique for an ASA-based graft copolymer which is excellent in not only impact resistance but also appearance and thermal stability.

It is an object of the present invention to solve the problems of the prior art described above, and an object of the present invention is to provide a method for improving the impact resistance and appearance of an acrylic graft copolymer and improving flowability while maintaining thermal stability, And a method for producing the acrylic graft copolymer which can be realized.

One aspect of the present invention relates to a method for producing a rubber-modified graft copolymer, comprising: (a) reacting a rubber-modified graft copolymer, an acrylic monomer, a first initiator, a crosslinking agent, and an emulsifier to form a structure comprising a layer of acrylic rubber on the surface of the rubber- Producing; And (b) grafting a copolymer comprising an aromatic vinyl monomer and an unsaturated nitrile monomer to the structure in the presence of a mercaptan-based molecular weight modifier and a second initiator, wherein the second initiator is a peroxycarbonate-based compound And the amount of the mercaptan-based molecular weight modifier is 0.1 to 0.5 parts by weight based on 100 parts by weight of the copolymer consisting of the aromatic vinyl monomer and the unsaturated nitrile monomer. The present invention also provides a method for producing the acrylic graft copolymer.

In one embodiment, the rubber-modified graft copolymer may be a copolymer in which an aromatic vinyl monomer and an unsaturated nitrile monomer are grafted to the conjugated diene rubber.

In one embodiment, the conjugated diene rubber is selected from the group consisting of 1,3-butadiene, 2-methyl-1,3-butadiene, 2-ethyl-1,3-butadiene and 2,3- One or more polymers or copolymers selected from the group consisting of

In one embodiment, the aromatic vinyl monomer is selected from the group consisting of styrene,? -Methylstyrene vinyltoluene, t-butylstyrene, halogen substituted styrene, 1,3-dimethylstyrene, 2,4-dimethylstyrene, And combinations thereof.

In one embodiment, the unsaturated nitrile monomer is selected from the group consisting of acrylonitrile, methacrylonitrile, ethacrylonitrile, phenyl acrylonitrile,? -Chloroacrylonitrile, and combinations of two or more thereof. .

In one embodiment, the acrylic monomer may be selected from the group consisting of (meth) acrylic acid, an alkyl (meth) acrylate having an alkyl group having 1 to 16 carbon atoms, and a combination of two or more thereof.

In one embodiment, the first initiator may be a water-soluble initiator.

In one embodiment, the first initiator may be selected from the group consisting of potassium persulfate, sodium persulfate, ammonium persulfate, silver persulfate, and combinations of at least two of the foregoing.

In one embodiment, the second initiator is selected from the group consisting of 2,5-dimethyl-2,5-di- (2-ethylhexanonylperoxy) hexane, t-amylperoxy-2-ethylhexanoate, (2-ethylhexyl) monoperoxycarbonate, t-butylisopropyl monoperoxycarbonate, 2,5-dimethyl-2,5-di (benzoylperoxy) Butyl peroxy-3,5,5-trimethylhexanoate, t-butyl peroxybenzoate, t-butyl peroxybenzoate, tert-butyl peroxyacetate, t- -Butyl peroxybenzoate, and combinations of two or more thereof.

In one embodiment, the mercaptan-based molecular weight adjuster may be one selected from the group consisting of n -decylmercaptan , n -dodecylmercaptan , t -dodecylmercaptan , n-octadecylmercaptan and combinations of two or more thereof have.

In one embodiment, the crosslinking agent is selected from the group consisting of ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate, 1,3-butanediol dimethacrylate, 1,6-hexanediol dimethacrylate, But are not limited to, acrylate, acrylate, acrylate, acrylate, neopentyl glycol dimethacrylate, trimethylolpropane trimethacrylate, trimethylolmethane triacrylate, aryl methacrylate, triarylamine, diarylamine, triarylisocyanurate, Rate, and a combination of two or more thereof.

In one embodiment, the emulsifier is selected from the group consisting of fatty acid soap, rosin acid, oleic acid, or an alkali salt of succinic acid; Alkyl aryl sulfonates; Alkaline methyl alkyl sulfates; Alkali alkyl sulfonates; Sulfonated alkyl esters; And a combination of two or more thereof.

In one embodiment, the average particle diameter of the conjugated diene rubber may be 250 nm to 350 nm.

In one embodiment, the amount of the crosslinking agent may be 0.1 to 0.5 parts by weight based on 100 parts by weight of the copolymer comprising the aromatic vinyl monomer and the unsaturated nitrile monomer.

According to one aspect of the present invention, the monomer is grafted around the rubber component,

A rubber-modified graft copolymer having a stiffness higher than a certain level on the surface thereof and an acrylic-

A structural body comprising a layer made of an acrylic rubber on the surface of the rubber-modified graft copolymer can be stably prepared by reacting the rubber-modified graft copolymer in the presence of a second initiator and a molecular weight modifier.

The acrylic graft copolymer in which an aromatic vinyl monomer and an unsaturated nitrile monomer are grafted to the above structure can provide balanced appearance and flowability while maintaining impact resistance and weather resistance.

It should be understood that the effects of the present invention are not limited to the effects described above, but include all effects that can be deduced from the description of the invention or the composition of the invention set forth in the claims.

Hereinafter, the present invention will be described in detail. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein.

Throughout the specification, when a part is referred to as being "connected" to another part, it includes not only "directly connected" but also "indirectly connected" . Also, when an element is referred to as "comprising ", it means that it can include other elements, not excluding other elements unless specifically stated otherwise.

One aspect of the present invention relates to a method for producing a rubber-modified graft copolymer, comprising: (a) reacting a rubber-modified graft copolymer, an acrylic monomer, a first initiator, a crosslinking agent, and an emulsifier to form a structure comprising a layer of acrylic rubber on the surface of the rubber- Producing; And (b) grafting a copolymer comprising an aromatic vinyl monomer and an unsaturated nitrile monomer to the structure in the presence of a mercaptan-based molecular weight modifier and a second initiator, wherein the second initiator is a peroxycarbonate-based compound And the amount of the mercaptan-based molecular weight modifier is 0.1 to 0.5 parts by weight based on 100 parts by weight of the copolymer consisting of the aromatic vinyl monomer and the unsaturated nitrile monomer. The present invention also provides a method for producing the acrylic graft copolymer.

In the step (a), a structure is prepared by reacting a rubber-modified graft copolymer and an acrylic monomer in the presence of a first initiator, a crosslinking agent, and an emulsifier to thereby form a layer comprising an acrylic rubber on the surface of the rubber-modified graft copolymer can do. The reaction may be a conventional emulsion polymerization reaction.

The activating agent may include sodium formaldehyde sulfoxylate, sodium ethylenediaminetetraacetate, ferrous sulfate, lactose, dextrose, sodium pyruvate, sodium sulphate and sodium pyruvate. And a combination of at least two of them. Preferably, sodium formaldehyde sulfoxylate, sodium ethylenediamine tetraacetate, and ferrous sulfate may be used.

The rubber-modified graft copolymer may be a copolymer obtained by grafting an aromatic vinyl monomer and an unsaturated nitrile monomer onto a conjugated diene rubber.

In order to improve the colorability, weatherability, and impact strength of the conventional acrylic graft copolymer, there has been proposed a method of using a multi-layer acrylate rubber polymer containing a diene rubber polymer therein. However, in order to form a plurality of shells It is difficult to control the reaction and the rigidity of the surface of the diene rubber which is the core part is low so that the acrylate rubber can not be effectively stacked thereon and it is difficult to achieve the required level of weatherability.

On the other hand, the rubber-modified graft copolymer is obtained by grafting an aromatic vinyl monomer and an unsaturated nitrile monomer onto the surface of the conjugated diene rubber and has a higher surface rigidity than the ungrafted conjugated diene rubber, The formed acrylic rubber can be stably separated without infiltrating into the conjugated diene rubber.

Further, the rubber-modified graft copolymer prepared at a conversion rate of 99% or more can be used to simplify the process and improve the reproducibility, without considering the conversion rate between the reaction as in the prior art.

The conjugated diene-based rubber contributes to impact resistance and coloring property. The acrylic rubber contributes to weathering resistance, and there is a tradeoff in the action effect of each rubber component. Therefore, when they are mixed arbitrarily, The effect that can be realized can be lowered together with the effect. For example, if the acrylic rubber formed on the surface is impregnated in the conjugated diene rubber in the inside, the weather resistance derived from the acrylic rubber in the final product is lowered, and the impact resistance and the coloring property derived from the conjugated diene rubber also deteriorate .

Since the structure is obtained by reacting and polymerizing an acrylic monomer on the surface of the above-mentioned conjugated copolymer in which an aromatic vinyl monomer and an unsaturated nitrile monomer are grafted on the surface of the conjugated diene rubber as a seed, A diene rubber, a monomer grafted on the surface thereof, and an acrylic rubber.

That is, in the structure, the conjugated diene rubber and the acrylic rubber are independently separated from each other by the monomers grafted to the surface of the conjugated diene rubber, and thus the weather resistance derived from the acrylic rubber and the conjugate Impact resistance and coloring property derived from a diene rubber can be balancedly realized.

Wherein the conjugated diene rubber is at least one selected from the group consisting of 1,3-butadiene, 2-methyl-1,3-butadiene, 2-ethyl-1,3-butadiene and 2,3- Polymers or copolymers, preferably homopolymers of 1,3-butadiene, but are not limited thereto.

The average particle size of the conjugated diene rubber may be 250 to 350 nm, and preferably 280 to 330 nm. When the average particle size of the conjugated diene rubber is less than 250 nm, the effect of imparting impact strength is weak. When the average particle size is more than 350 nm, the gloss and coloring property of the final product may be deteriorated.

The content of the conjugated diene rubber may be 10 to 40% by weight, based on the total weight of the rubber component contained in the structure, that is, the conjugated diene rubber and the acrylic rubber

have. If the content of the conjugated diene rubber is less than 10% by weight, impact resistance and coloring property may be deteriorated. If the content is more than 40% by weight, a layer made of an acrylic rubber may not be formed.

Wherein the aromatic vinyl monomer is selected from the group consisting of styrene,? -Methylstyrene vinyltoluene, t-butylstyrene, halogen substituted styrene, 1,3-dimethylstyrene, 2,4-dimethylstyrene and ethylstyrene, And may be selected. Preferably, it may be styrene, but is not limited thereto.

The unsaturated nitrile monomer may be selected from the group consisting of acrylonitrile, methacrylonitrile, ethacrylonitrile, phenyl acrylonitrile,? -Chloroacrylonitrile, and combinations of two or more thereof, , Acrylonitrile, but are not limited thereto.

The acrylic monomer may be selected from the group consisting of (meth) acrylic acid, an alkyl (meth) acrylate having an alkyl group having 1 to 16 carbon atoms, and a combination of two or more thereof, preferably butyl acrylate , But is not limited thereto.

The acrylic monomer can be polymerized smoothly on the surface of the rubber-modified graft copolymer by introducing a water-soluble initiator suitable for the emulsion polymerization reaction as an initiator for imparting a radical to the rubber-modified graft copolymer.

The amount of the first initiator may be 0.1 to 5 parts by weight. If the amount of the first initiator is less than 0.1 parts by weight, the reaction rate and the conversion of the acrylic monomer may be lowered. If the amount is less than 5 parts by weight, the molecular weight and the average particle size of the structure may be decreased, .

The first initiator is a water-soluble initiator, which may be a persulfate-based compound, and is preferably selected from the group consisting of potassium persulfate, sodium persulfate, ammonium persulfate, silver persulfate, and combinations of two or more thereof. But is not limited thereto.

In the structure, the rubber-modified graft copolymer and the acrylic rubber may be bonded by a crosslinking agent. The cross-linking agent is capable of linking the acrylic monomer with a radical generated on the surface or the outskirt of the rubber-modified graft copolymer by the first initiator, and the acrylic monomer and the acrylic rubber, You can also connect.

The crosslinking agent may form a strong bond between the rubber-modified graft copolymer and the acrylic rubber to stabilize the structure.

The amount of the cross-linking agent may be 0.1 to 5 parts by weight. If the amount of the cross-linking agent is less than 0.1 part by weight, the acrylic rubber is hardly produced on the surface of the rubber-modified graft copolymer, and if it is more than 5 parts by weight, the impact resistance may be lowered.

Wherein the crosslinking agent is selected from the group consisting of ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate, 1,3-butanediol dimethacrylate, 1,6-hexanediol dimethacrylate, neopentyl glycol Dimethacrylate, trimethylolpropane trimethacrylate, trimethylolmethane triacrylate, arylmethacrylate, triarylamine, diarylamine, triarylisocyanurate, triarylcyanurate, and 2 of these And combinations thereof. Preferably, triaryl cyanurate is used, but the present invention is not limited thereto.

The amount of the emulsifier may be 0.1 to 5 parts by weight. If the amount of the emulsifier is less than 0.1 parts by weight, the stability of the latex may deteriorate to increase the amount of the coagulated product. If the amount of the emulsifier is more than 5 parts by weight, the average particle size of the structure may be decreased.

The emulsifier may be selected from the group consisting of fatty acid soap, rosin acid, oleic acid, or an alkali salt of succinic acid; Alkyl aryl sulfonates; Alkaline methyl alkyl sulfates; Alkali alkyl sulfonates; Sulfonated alkyl esters; And a combination of at least two of them, preferably dioctyl sulfosuccinate, but is not limited thereto.

Meanwhile, in the step (b), 30 to 120 parts by weight of an aromatic vinyl monomer and 20 to 60 parts by weight of an unsaturated nitrile monomer may be copolymerized with the structure to prepare an acrylic graft copolymer.

The copolymerization in the step (b) may be carried out by a conventional emulsion polymerization reaction. After the reaction, the latex-phase product is agglomerated and dried to obtain a powdery acrylic graft copolymer.

Wherein the second initiator is at least one selected from the group consisting of 2,5-dimethyl-2,5-di- (2-ethylhexanonylperoxy) hexane, t-amylperoxy-2-ethylhexanoate, (Isobutyl) hexanoate, t-amyl (2-ethylhexyl) monoperoxycarbonate, t-butylisopropyl monoperoxycarbonate, 2,5-dimethyl- (2-ethylhexyl) monoperoxycarbonate, t-amyl peroxybenzoate, tertiary butyl peroxyacetate, t-butyl peroxy-3,5,5-trimethylhexanoate, t-butyl peroxybenzoate And a combination of at least two of them, and may preferably be t-butylisopropyl monoperoxycarbonate or t-butyl- (2-ethylhexyl) monoperoxycarbonate, It is not.

The mercaptan-based molecular weight adjuster may be selected from the group consisting of n -decylmercaptan , n -dodecylmercaptan , t -dodecylmercaptan , n-octadecylmercaptan and combinations of two or more thereof, preferably 3 - dodecyl mercaptan, but is not limited thereto.

The mercaptan-based molecular weight modifier may be contained in an amount of 0.1 to 0.5 parts by weight, preferably 0.2 to 0.4 parts by weight, based on 100 parts by weight of the copolymer of the aromatic vinyl monomer and the unsaturated nitrile monomer, and the mercaptan- If the amount is less than 0.5 part by weight, the mechanical properties may be greatly deteriorated.

Hereinafter, embodiments of the present invention will be described in detail.

Example 1

300 parts by weight of ion-exchanged water and 50 parts by weight (based on solid content) of ABS latex were heated to 70 占 폚 in an atmosphere substituted with nitrogen, and then 1 part by weight of potassium persulfate as a first initiator was added thereto and stirred for 10 minutes. Then, a mixture of 100 parts by weight of butyl acrylate and 1 part by weight of triarylcyanurate as a crosslinking agent and 1 part by weight of dioctylsulfosuccinate as an emulsifier was continuously added for 4 hours to polymerize. The polymerized product was further agitated at a temperature of 70 캜 for 1 hour and aged to obtain rubber particles.

6 parts by weight of ion-exchanged water and 50 parts by weight of TDDM were added to 50 parts by weight (based on solid content) of the rubber particles, 0.1 part by weight were continuously introduced for 4 hours to perform graft polymerization. At the same time, 1.5 parts by weight of the emulsifier, 0.2 part by weight of peroxycarbonate t-butyl isopropyl monoperoxycarbonate as the second initiator, and 10 parts by weight of ion-exchanged water were added for 4 hours and 30 minutes. And then further stirred for 1 hour for the aging process to obtain an acrylate-styrene-acrylonitrile latex.

Example 2

A graft copolymer latex was obtained in the same manner as in Example 1 except that the amount of the 3-dodecylmercaptan to be added was changed to 0.2 part by weight.

Example 3

A graft copolymer latex was obtained in the same manner as in Example 1 except that t-butyl (2-ethylhexyl) monoperoxycarbonate was used instead of t-butylisopropyl monoperoxycarbonate as a second initiator .

Comparative Example 1

A graft copolymer latex was obtained in the same manner as in Example 1 except that the molecular weight modifier 3-dodecylmercaptan was omitted.

Comparative Example 2

A graft copolymer latex was obtained in the same manner as in Example 1 except that the amount of the 3-dodecylmercaptan to be added was changed to 0.3 part by weight.

Comparative Example 3

A graft copolymer latex was obtained in the same manner as in Example 1 except that cumene hydroperoxide was used instead of t-butyl isopropyl monoperoxycarbonate as a second initiator.

Comparative Example 4

Graft copolymer latex was obtained in the same manner as in Example 1 except that ASA latex (KUMHO ASA latex, rubber size: 300), which is a sole rubber not containing diene rubber, was used instead of ABS latex.

Experimental Example

ASA powder was obtained through coagulation and drying of the latex prepared in Examples and Comparative Examples.

Each of the ASA dry powders prepared thereafter was kneaded with ordinary styrene-acrylonitrile (SAN). At this time, 22 parts by weight of ASA powder rubber was added to 100 parts by weight of the SAN resin composition, and 0.2 parts by weight of an antioxidant, 0.7 parts by weight of a lubricant and 2 parts by weight of a black colorant were mixed. The specimens were then prepared using a twin extruder and an extruder at a temperature of 230 ° C.

The physical property evaluation items and evaluation methods for the specimens are as follows.

- Impact strength (kgf · cm / cm): The specimen thickness was 3.2 mm and measured according to ASTM D256.

- Coloring degree: The L value was measured using a spectrocolorimeter (Datacolor 650). The lower the L value, the better the coloring streak.

- Gloss: Gloss was measured using a Micro Haze Plus at a 60 degree angle.

Flowability (MI): measured according to ASTM D1238 at 220 ° C, 10 kg.

-Flow mark: The presence of flow mark was visually confirmed by using a three-stage color specimen with a height deviation. (Yes: Yes, No X).

- Heat Stability (ΔGloss): The glossiness change (ΔGloss) before and after retention of the molded specimen after staying in the screw of the injection molding machine set at 240 ° C. for 10 minutes was shown. .

Weatherability: The degree of discoloration (? E) of the color difference meter was measured after exposure to 4,500 KJ / m2 in accordance with SAEJ2527 with a weatherometer. Here,? E is an arithmetic mean value of the CIE Lab values before and after the stay, and the closer to 0, the better the thermal stability. The colorimeter was measured using Datacolor 650.

- Grafting ratio (%): Tetrahydrofuran (THF) was added to 0.5 g of the acrylic graft copolymer powder, stirred at room temperature for 24 hours, and centrifuged to collect only the portion not soluble in THF. Was measured by the following equation.

Graft rate (%) = (weight of grafted monomer / weight of core polymer) x 100

division Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Impact strength 23 21 22 23 12 22 15 Coloration degree 27.5 27.6 27.5 27.5 27.8 27.6 29.5 Surface gloss 93 94 93 87 84 90 93 Flowability 16 21 15 9 27 15 15 Flow mark X X X O X X X Thermal stability 9 11 8 8 23 19 10 Weatherability 15.6 16.2 15.9 15.3 18.2 17.4 15.5 Graft rate 43 35 44 51 20 28 45

Referring to Table 1, 0.1 to 0.5 part by weight of the amount of the molecular weight mercaptan-based molecular weight modifier is added to 100 parts by weight of the copolymer consisting of the aromatic vinyl monomer and the unsaturated nitrile monomer, and a peroxycarbonate-based initiator In Examples 1 to 3, the impact strength, surface gloss, flow property, flow mark, thermal stability and graft ratio were all improved as compared with Comparative Examples 1 to 3 which were not. Also, in Comparative Example 4 using ASA latex instead of ABS latex, a significantly lower value of impact strength was obtained.

It will be understood by those skilled in the art that the foregoing description of the present invention is for illustrative purposes only and that those of ordinary skill in the art can readily understand that various changes and modifications may be made without departing from the spirit or essential characteristics of the present invention. will be. It is therefore to be understood that the above-described embodiments are illustrative in all aspects and not restrictive. For example, each component described as a single entity may be distributed and implemented, and components described as being distributed may also be implemented in a combined form.

The scope of the present invention is defined by the appended claims, and all changes or modifications derived from the meaning and scope of the claims and their equivalents should be construed as being included within the scope of the present invention.

Claims (14)

(a) reacting a rubber-modified graft copolymer, an acrylic monomer, a first initiator, a crosslinking agent, and an emulsifier to produce a structure comprising a layer of acrylic rubber on the surface of the rubber-modified graft copolymer; And
(b) grafting a copolymer comprising an aromatic vinyl monomer and an unsaturated nitrile monomer to the structure in the presence of a mercaptan-based molecular weight modifier and a second initiator,
Wherein the second initiator is a peroxycarbonate compound,
Wherein the amount of the mercaptan-based molecular weight modifier is 0.1 to 0.5 parts by weight based on 100 parts by weight of the copolymer of the aromatic vinyl monomer and the unsaturated nitrile monomer. The method according to claim 1,
Wherein the rubber-modified graft copolymer is a copolymer obtained by grafting an aromatic vinyl monomer and an unsaturated nitrile monomer onto a conjugated diene rubber. 3. The method of claim 2,
Wherein the conjugated diene rubber is at least one selected from the group consisting of 1,3-butadiene, 2-methyl-1,3-butadiene, 2-ethyl-1,3-butadiene and 2,3- A method for producing an acrylic graft copolymer, which is a polymer or a copolymer. 3. The method of claim 2,
Wherein the aromatic vinyl monomer is selected from the group consisting of styrene,? -Methylstyrene vinyltoluene, t-butylstyrene, halogen substituted styrene, 1,3-dimethylstyrene, 2,4-dimethylstyrene and ethylstyrene, Wherein the graft copolymer is a selected one. 3. The method of claim 2,
Wherein the unsaturated nitrile monomer is at least one selected from the group consisting of acrylonitrile, methacrylonitrile, ethacrylonitrile, phenyl acrylonitrile,? -Chloroacrylonitrile, and combinations of at least two of the foregoing. ≪ / RTI > The method according to claim 1,
Wherein the acrylic monomer is one selected from the group consisting of (meth) acrylic acid, an alkyl (meth) acrylate having an alkyl group having 1 to 16 carbon atoms, and a combination of at least two of the foregoing. The method according to claim 1,
Wherein the first initiator is a water-soluble initiator. 8. The method of claim 7,
Wherein the first initiator is selected from the group consisting of potassium persulfate, sodium persulfate, ammonium persulfate, silver persulfate, and combinations of at least two of the foregoing. The method according to claim 1,
Wherein the second initiator is at least one selected from the group consisting of 2,5-dimethyl-2,5-di- (2-ethylhexanonylperoxy) hexane, t-amylperoxy-2-ethylhexanoate, (Isobutyl) hexanoate, t-amyl (2-ethylhexyl) monoperoxycarbonate, t-butylisopropyl monoperoxycarbonate, 2,5-dimethyl- (2-ethylhexyl) monoperoxycarbonate, t-amylperoxy benzoate, tertiary butyl peroxyacetate, t-butyl peroxy-3,5,5-trimethylhexanoate, and t-butyl peroxybenzoate And a combination of two or more of the foregoing. The method according to claim 1,
Wherein the mercaptan-based molecular weight modifier is one selected from the group consisting of n -decylmercaptan , n -dodecylmercaptan , t -dodecylmercaptan , n-octadecylmercaptan and combinations of two or more thereof. Gt; The method according to claim 1,
Wherein the crosslinking agent is selected from the group consisting of ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate, 1,3-butanediol dimethacrylate, 1,6-hexane diol dimethacrylate, neopentyl glycol Dimethacrylate, trimethylolpropane trimethacrylate, trimethylolmethane triacrylate, arylmethacrylate, triarylamine, diarylamine, triarylisocyanurate, triarylcyanurate, and 2 of these Wherein the graft copolymer is one selected from the group consisting of the above-mentioned combinations. The method according to claim 1,
Wherein the emulsifier is selected from the group consisting of fatty acid soap, rosin acid, oleic acid, or an alkali salt of succinic acid; Alkyl aryl sulfonates; Alkaline methyl alkyl sulfates; Alkali alkyl sulfonates; Sulfonated alkyl esters; And a combination of two or more of the foregoing. The method of claim 3,
Wherein the conjugated diene rubber has an average particle diameter of 250 nm to 350 nm. 12. The method of claim 11,
Wherein the amount of the crosslinking agent is 0.1 to 0.5 parts by weight based on 100 parts by weight of the copolymer comprising the aromatic vinyl monomer and the unsaturated nitrile monomer.