阅读说明：本技术 热塑性共聚物的制备方法、由其制备的热塑性共聚物和包含它的热塑性树脂组合物 (Method for preparing thermoplastic copolymer, thermoplastic copolymer prepared therefrom, and thermoplastic resin composition comprising the same ) 是由 朱玟徹 申珉承 洪晟元 金仁秀 李亨燮 于 2019-12-04 设计创作，主要内容包括：本发明涉及一种使用单体液滴制备热塑性共聚物的方法、由其制备的热塑性共聚物和包含所述热塑性共聚物的热塑性树脂组合物。在所述制备方法中,在引发聚合之后,在聚合转化率达到10％之后注入包含芳香族乙烯基类单体的单体液滴以参与反应,并且可以以高产率制备具有增加的平均粒径的热塑性共聚物。(The present invention relates to a method for preparing a thermoplastic copolymer using monomer droplets, a thermoplastic copolymer prepared therefrom, and a thermoplastic resin composition comprising the same. In the production method, after the initiation of polymerization, monomer droplets containing an aromatic vinyl-based monomer are injected to participate in the reaction after the polymerization conversion rate reaches 10%, and a thermoplastic copolymer having an increased average particle diameter can be produced with high yield.)

1. A method of making a thermoplastic copolymer comprising: polymerizing a first aromatic vinyl monomer and a vinyl cyanide monomer in the presence of a polymerization initiator,

the monomer droplets prepared by mixing the water-soluble solvent, the dispersant and the second aromatic vinyl-based monomer are injected after the polymerization conversion rate reaches 10% during the polymerization.

2. The method for preparing a thermoplastic copolymer according to claim 1, wherein the monomer droplets contain 5 to 70 wt% of the second aromatic vinyl-based monomer.

3. The method of preparing a thermoplastic copolymer according to claim 1, wherein the monomer droplets contain 0.5 to 2.0 parts by weight of the dispersant based on 100 parts by weight of the second aromatic vinyl-based monomer.

4. The method for producing a thermoplastic copolymer according to claim 1, wherein the average particle diameter of the monomer droplets is 50 to 300 μm.

5. The method for producing a thermoplastic copolymer according to claim 1, wherein the monomer droplets are injected in such an amount that the weight ratio of the first aromatic vinyl monomer to the second aromatic vinyl monomer is 80:20 to 50: 50.

6. The method for producing a thermoplastic copolymer according to claim 1, wherein the monomer droplets are continuously injected,

the continuous injection is started at a time point when the polymerization conversion rate is 10% or more and terminated at a time point when the polymerization conversion rate is 60% or less, and the entire amount of the monomer droplets is injected at a constant rate from the start of injection to the termination of injection.

7. The method of producing a thermoplastic copolymer according to claim 1, wherein the method uses the vinyl cyano monomer and the total amount of the first aromatic vinyl monomer and the second aromatic vinyl monomer in a weight ratio of 60:40 to 80: 20.

8. The method for producing a thermoplastic copolymer according to claim 1, wherein the polymerization is suspension polymerization.

9. The method for preparing a thermoplastic copolymer according to claim 1, wherein the polymerization is performed by additionally injecting one or more additives selected from a polymerization solvent, a dispersant, a molecular weight regulator, and a dispersion promoter.

10. The method for preparing a thermoplastic copolymer according to claim 1, wherein the polymerization is performed at a temperature ranging from 80 ℃ to 150 ℃.

11. The method for producing a thermoplastic copolymer according to claim 1, wherein the amount of fine particles produced in the production method is 0.5 to 0.7% by weight.

12. A thermoplastic copolymer having an average particle diameter of 400 to 600 μm and being a suspension polymer of an aromatic vinyl-based monomer and a vinyl cyano-based monomer.

13. A thermoplastic resin composition comprising the thermoplastic copolymer of claim 12 and an acrylonitrile-butadiene-styrene copolymer.

Technical Field

[ Cross-reference to related applications ]

The present application claims the benefit of priority based on korean patent application No.10-2018-0158019, filed on 10.12.2018, the entire contents of which are incorporated herein by reference.

Background

In general, styrenic copolymers have excellent moldability, rigidity and electrical properties, and are widely used in various industrial fields including OA products such as computers, printers and copiers, home appliances such as televisions and audio systems, electric and electronic parts, automobile parts, miscellaneous goods and the like.

Such styrenic copolymers are prepared by emulsion polymerization, suspension polymerization or bulk polymerization.

By the preparation method of emulsion polymerization, the size of particles prepared thereby is smaller than that of particles prepared by other polymerization methods, and therefore, the surface area capable of participating in polymerization can be largely distributed, temperature control of the reaction system can be easy, polymerization can be carried out in a rapid period of time, and stable polymerization can be achieved. However, since unreacted monomers, polymerization additives, etc. remain, there are problems of coloring and discoloration of the copolymer, and since a curing process is performed after the polymerization reaction is finished to prepare a slurry, and a post-treatment process of washing, dehydrating, and drying the slurry is required, there are problems of reduction in production efficiency and treatment of equipment and wastewater.

In contrast, the preparation methods by suspension polymerization and bulk polymerization require a significantly small amount of additives, and the post-treatment process is simple, and the coloring problem of the final product is rarely generated. However, by bulk polymerization, productivity may be excellent when compared to other polymerization methods, but there is a limitation in application to production of various species in small amounts.

Meanwhile, by suspension polymerization, the amount of additives used is small, the post-treatment process is relatively simple, and the method can be easily applied to produce various kinds in small amounts.

Suspension polymerization is generally carried out by injecting water, a dispersant, a monomer, a polymerization initiator, and the like into a reactor in batches with stirring and polymerizing. If a monomer partially dissolved in water is used, the ratio of the initially injected monomer and the ratio of the monomer participating in the initial polymerization may become different. For example, if suspension polymerization is performed using an aromatic vinyl-based monomer and a vinyl cyanide-based monomer, the vinyl cyanide-based monomer may be partially dissolved in water, and thus, the proportion of the vinyl cyanide-based monomer involved in the initial polymerization may be changed compared to the injection proportion of the vinyl cyanide-based monomer, whereby only the vinyl cyanide-based monomer may be continuously combined with the end of the polymer chain, and a polymer having an uneven composition may be prepared, and defects of deterioration of physical properties and increase of yellow index may occur.

In order to compensate for the disadvantages of the suspension polymerization, a method of partially injecting a part of the monomer into the polymer has been proposed, but there is a problem of a decrease in yield due to an increase in the generation of fine particles.

Therefore, it is required to develop a method for preparing a copolymer by suspension polymerization, by which improvement of yellowness index and yield can be simultaneously achieved.

Disclosure of Invention

Technical problem

An object of the present invention is to provide a method for preparing a thermoplastic copolymer, by which the generation of fine particles is reduced and the yield is improved.

Further, another object of the present invention is to provide a thermoplastic copolymer prepared by the above preparation method, which has an increased average particle diameter when compared with conventional suspension polymerization.

Further, another object of the present invention is to provide a thermoplastic resin composition comprising the thermoplastic copolymer.

Technical scheme

In order to solve the above-mentioned task, in the present invention, there is provided a method for preparing a thermoplastic copolymer, comprising: polymerizing a first aromatic vinyl monomer and a vinyl cyanide monomer in the presence of a polymerization initiator, wherein a monomer droplet prepared by mixing a polymerization solvent, a dispersant and a second aromatic vinyl monomer is injected after a polymerization conversion rate reaches 10% during polymerization.

In another aspect, the present invention provides a thermoplastic copolymer having an average particle diameter of 400 to 600 μm and being a suspension polymer of an aromatic vinyl-based monomer and a vinyl cyano-based monomer.

Further, the present invention provides a thermoplastic resin composition comprising the thermoplastic copolymer and an acrylonitrile-butadiene-styrene-based copolymer.

Advantageous effects

By the production method according to the present invention, in the polymerization process, specifically, after the polymerization is initiated and after the polymerization conversion rate reaches 10%, the monomer droplets containing the aromatic vinyl-based monomer are injected to participate in the reaction, the ratio imbalance between the monomers in the polymer system can be reduced, the generation of fine particles can be reduced, the decrease in the yield due to the fine particles can be suppressed, and the thermoplastic copolymer can be produced with high yield.

In addition, the thermoplastic copolymer according to the present invention is prepared by the preparation method according to the present invention, by which monomer droplets are injected during the polymerization is performed, and a significantly increased average particle diameter can be obtained when compared to a copolymer prepared by conventional suspension polymerization.

In addition, the thermoplastic resin composition comprising the thermoplastic copolymer according to the present invention has an average particle diameter similar to that of the acrylonitrile-butadiene-styrene copolymer included in the resin composition injected into the resin composition together with the thermoplastic copolymer, and roll mixing grinding (rolling mixing) may become excellent, and thus, the performance of yellow index may become excellent.

Detailed Description

Hereinafter, the present invention will be described in more detail to help understanding the present invention.

It should be understood that the words or terms used in the specification and claims should not be construed as meaning defined in commonly used dictionaries. It should also be understood that these words or terms should be interpreted as having meanings consistent with their meanings in the technical idea of the present invention on the basis of the principle that the inventor can appropriately define the meanings of the words or terms to best explain the present invention.

Unless otherwise defined separately, terms and measurement methods used in the present invention may be defined as follows.

[ terms ]

The term "composition" as used herein includes mixtures comprising materials of the respective compositions as well as reaction products formed from materials of the respective compositions and decomposition products of the respective compositions.

The term "derived unit" as used herein may refer to a structure derived from a particular substance or to the substance itself.

The terms "first aromatic vinyl monomer" and "second aromatic vinyl monomer" used in the present invention denote the same aromatic vinyl monomer, and "first" and "second" may be expressions for distinguishing the time or shape participating in the polymerization reaction.

The term "aromatic vinyl-based monomer" used in the present invention may be one or more selected from the group consisting of styrene, α -methylstyrene, α -ethylstyrene, p-methylstyrene, o-tert-butylstyrene, bromostyrene, chlorostyrene, trichlorostyrene and derivatives thereof, and specifically, styrene.

The term "vinyl cyano-based monomer" used in the present invention may be one or more selected from acrylonitrile, methacrylonitrile, ethacrylonitrile and derivatives thereof, and specifically, acrylonitrile.

The term "conjugated diene-based monomer" used in the present invention may be one or more selected from the group consisting of 1, 3-butadiene, 2, 3-dimethyl-1, 3-butadiene, 2-ethyl-1, 3-butadiene, 1, 3-pentadiene and isoprene, and specifically, 1, 3-butadiene.

The term "derivative" used in the present invention may denote a compound having a structure obtained by substituting one or more hydrogen atoms constituting the original compound with a halogen group, an alkyl group or a hydroxyl group.

The term "monomer droplet" used in the present invention means a substance having a micelle structure in which monomer particles are contained, for example, a substance containing monomer particles in micelles formed by a dispersant.

The term "fine particles" used in the present invention may mean particles having a particle diameter of 61 μm or less, which are by-products from monomers that do not form a copolymer.

[ measuring method ]

In the present invention, the "average particle diameter" is obtained by passing each copolymer one by one through standard sieves of 2000. mu.m, 1400. mu.m, 850. mu.m, 425. mu.m, 150. mu.m, 106. mu.m and 75. mu.m, obtaining the weight percentage by measuring the weight of the copolymer passing through each sieve, and calculating the average value thereof.

In the present invention, "polymerization conversion rate" means a degree of forming a polymer by polymerizing monomers, and may be calculated by partially collecting the polymer in a reactor during polymerization and by the following mathematical formula 1.

[ mathematical formula 1]

Polymerization conversion (%) [ (total amount of injected monomer-total amount of unreacted monomer)/total amount of injected monomer ] × 100

The present invention provides a method for producing a thermoplastic copolymer having a small amount of fine particles with a high yield.

The production method according to an embodiment of the present invention is characterized by comprising: polymerizing a first aromatic vinyl monomer and a vinyl cyanide monomer in the presence of a polymerization initiator; and injecting monomer droplets prepared by mixing a polymerization solvent, a dispersant and a second aromatic vinyl-based monomer after the polymerization conversion rate reaches 10% during the polymerization.

The copolymer of the aromatic vinyl-based monomer and the vinyl cyano-based monomer is generally prepared by a preparation method of emulsion polymerization, bulk polymerization or suspension polymerization, wherein the suspension polymerization has advantages of a small amount of the additive, a relatively simple post-treatment process, and facilitation of production of various products in a small amount. However, the suspension polymerization is a batch type polymerization, and a reactant containing a monomer for polymerization is injected into a reactor in batches before initiation of polymerization, in which case a vinyl cyano monomer slightly soluble in water is dissolved, and an aromatic vinyl monomer and only a part of the vinyl cyano monomer participate in polymerization reaction at an initial stage of polymerization. As the polymerization proceeds, only the vinyl cyano-based monomer remains and continues the polymerization reaction, and only the derived units of the vinyl cyano-based monomer are continuously combined at the terminal portion to prepare a copolymer having a non-uniform structure, thereby causing a defect with respect to color such as an increase in yellow index. Therefore, after initiating polymerization, the method of controlling the ratio imbalance between monomers in the polymerization process by partially injecting a part of the monomers in the polymerization process as described above, but before forming a copolymer, a part of the partially injected monomers partially reacts with the polymerization initiator that has been injected at the time of polymerization initiation to form minute particles, and even, the generation of minute particles increases, the control of the ratio imbalance between monomers in the polymer system becomes insignificant, and the yield decreases.

However, in the production method according to one embodiment of the present invention, the monomer droplets are injected into the polymer system during suspension polymerization after initiation of polymerization and at a point in time when the polymerization conversion rate is 10% or more, so that the monomer droplets participate in polymerization, the reaction between the polymer initiator and the monomers in the monomer droplets can be suppressed, and the control of the ratio imbalance between the monomers in the polymer system can be made smooth while suppressing generation of fine particles. Therefore, a thermoplastic copolymer that solves color defects such as yellow index can be produced in high yield.

Hereinafter, a preparation method according to an embodiment of the present invention will be described in more detail.

The preparation method is a method of preparing a copolymer of an aromatic vinyl-based monomer and a vinyl cyano-based monomer, and may be performed by polymerizing a first aromatic vinyl-based monomer and a vinyl cyano-based monomer in the presence of a polymerization initiator, wherein a monomer droplet is injected after a polymerization conversion rate reaches 10%. Here, the polymerization may be suspension polymerization.

Specifically, polymerization may be initiated by injecting a polymerization initiator, a first aromatic vinyl-based monomer, and a vinyl cyanide-based monomer into a polymerization reactor, and monomer droplets may be injected and participate in polymerization reaction at a time point when the polymerization conversion rate reaches 10% or more after the initiation of polymerization.

The polymerization initiator is used to easily initiate polymerization, and is not particularly limited as long as it does not cause adverse effects, and may be, for example, selected from 2, 5-dimethyl-2, 5-di (t-butylperoxy) hexane, di (t-butylperoxyisopropyl) benzene, t-butylcumyl peroxide, di (t-amyl) peroxide, dicumyl peroxide, butyl 4, 4-di (t-butylperoxy) valerate, t-butyl peroxybenzoate, 2-di (t-butylperoxy) butane, t-amyl peroxybenzoate, t-butylperoxyacetate, t-butylperoxy (2-ethylhexyl) carbonate, t-butylperoxyisopropyl carbonate, t-butylperoxy-3, 5, 5-trimethyl-hexanoate, 1-di (t-butylperoxy) cyclohexane, t-amyl peroxy acetate, t-amyl peroxy- (2-ethylhexyl) carbonate, 1-bis (t-butylperoxy) -3,5, 5-trimethylcyclohexane, 1-bis (t-amyl peroxy) cyclohexane, t-butyl monoperoxy-maleate, 1' -azobis (hexahydrobenzonitrile) and 1,1' -azobis (cyclohexane-1-carbonitrile), and specifically, may be one or more selected from the group consisting of dicumyl peroxide, 1-bis (t-butylperoxy) cyclohexane and 1,1' -azobis (cyclohexanecarbonitrile).

In addition, the polymerization initiator may be used in an amount of 0.001 to 0.5 parts by weight, specifically, 0.003 to 0.45 parts by weight, or 0.06 to 0.25 parts by weight, based on 100 parts by weight of the total amount of the monomers for polymerization, i.e., the aromatic vinyl-based monomer and the vinyl cyano-based monomer. If the amount is within the range, the polymerization reaction can be more easily carried out and the polymerization conversion rate can be further improved.

The monomer droplets are prepared by mixing a water-soluble solvent, a dispersant, and a second aromatic vinyl-based monomer, and may have an average particle diameter of 50 to 300 μm, and may include 5 to 70 wt%, specifically, 10 to 50 wt% of the second aromatic vinyl-based monomer.

In addition, the monomer droplets may include 0.5 to 2.0 parts by weight of the dispersant based on 100 parts by weight of the second aromatic vinyl-based monomer, and in this case, the reaction of the polymerization initiator with the second aromatic vinyl-based monomer after the injection of the monomer droplets may be easily suppressed, the generation amount of fine particles may be effectively reduced, and the ratio imbalance between the monomers in the polymer system may be effectively improved.

The dispersing agent is not particularly limited as long as it does not adversely affect the polymerization, and may be, for example, one or more selected from the group consisting of water-soluble polyvinyl alcohol, partially saponified polyvinyl alcohol, polyacrylic acid, a copolymer of vinyl acetate and anhydrous maleic acid, hydroxypropylmethylcellulose, gelatin, calcium phosphate, tripotassium phosphate, hydroxyapatite, sorbitan monolaurate, sorbitan trioleate, polyoxyethylene, sodium lauryl sulfate, sodium dodecylbenzenesulfonate and sodium dioctylsulfosuccinate, specifically, tripotassium phosphate.

In addition, the water-soluble solvent may be water, in which case the water may be ion-exchanged water or deionized water.

Meanwhile, the injection amount of the monomer droplets may be such that the weight ratio of the first aromatic vinyl-based monomer to the second aromatic vinyl-based monomer is 80:20 to 50: 50. In this case, the imbalance in the ratio between the monomers in the polymer system can be effectively suppressed, and the ratio between the monomers in the polymer system can be kept in balance from the initiation of the polymerization to the termination of the polymerization. Therefore, a copolymer having a uniform structure can be formed, and problems related to color, such as yellow index, of the copolymer thus prepared can be solved.

In addition, the monomer droplets may be injected after the initiation of polymerization and during the progress of polymerization, and the injection may be intermittent injection, partial injection, or continuous injection, but may be continuous injection in view of effectively suppressing the ratio imbalance between the monomers in the polymer system.

In addition, in the production method according to an embodiment of the present invention, the monomer droplets may be injected at a time point at which the polymerization conversion rate is 10% or more, specifically, 10% to 60%, and in this case, the proportion of the monomer participating in the polymerization reaction in the polymer system may be kept in equilibrium throughout the polymerization reaction.

Still more specifically, the monomer droplets may be continuously injected, and according to the continuous injection, the injection may be started at a time point at which the polymerization conversion rate is 10% or more, and may be terminated at a time point at which the polymerization conversion rate is within 60%. The total amount of monomer droplets may be injected at a constant rate from the start of injection to the end of injection.

Meanwhile, in the preparation method, the aromatic vinyl-based monomer and the vinyl cyanide-based monomer may be used in a weight ratio of 60:40 to 80:20, and here, the aromatic vinyl-based monomer may include the first aromatic vinyl-based monomer and the second aromatic vinyl-based monomer included in the monomer droplet, that is, may refer to the total amount of the first aromatic vinyl-based monomer and the second aromatic vinyl-based monomer. If the aromatic vinyl-based monomer and the vinyl cyano-based monomer are used within the above-mentioned ranges, a copolymer having even better heat resistance, chemical resistance, mechanical properties and processability can be prepared.

In addition, the polymerization may be performed under any conditions under which the polymerization reaction can be easily achieved without particular limitation, for example, in a temperature range of 80 ℃ to 150 ℃, and in this case, the polymerization conversion rate may be increased more.

In addition, the polymerization may be performed by additionally injecting one or more additives selected from a polymerization solvent, a dispersant, a molecular weight regulator, and a dispersion accelerator.

The polymerization solvent may be water, in which case the water may be ion-exchanged water or deionized water.

The dispersing agent may be the same as described above, and may be the same as or different from the dispersing agent used to prepare the monomer droplets. The dispersant may be used in an amount of 0.5 parts by weight to 2.0 parts by weight, or 1.0 part by weight to 1.5 parts by weight, based on 100 parts by weight of the total amount of monomers used for polymerization, and if the amount is within the above range, dispersion stability of the monomers in the polymer system may be improved and a copolymer having more uniform particles may be prepared.

In addition, the molecular weight modifier is not particularly limited as long as it does not adversely affect the polymerization reaction, and may be, for example, one or more selected from the group consisting of α -methylstyrene dimer, t-dodecylmercaptan, n-dodecylmercaptan, octylmercaptan, carbon tetrachloride, methylene chloride, dibromomethane, tetraethylthiuram disulfide, dipentylidene thiuram disulfide and diisopropyl xanthogen disulfide, specifically, t-dodecylmercaptan. Further, the molecular weight regulator may be used in an amount of 0.01 to 0.15 parts by weight or 0.05 to 0.1 parts by weight, based on 100 parts by weight of the total amount of monomers used for polymerization, and if the amount is within the above range, a copolymer having an appropriate weight average molecular weight may be prepared.

Here, the total amount of the monomers represents the total amount of the first aromatic vinyl monomer, the second aromatic vinyl monomer, and the vinyl cyano monomer.

In addition, the present invention provides a thermoplastic copolymer prepared by the preparation method.

The thermoplastic copolymer according to an embodiment of the present invention may have an average particle diameter of 400 to 600 μm and may be characterized as a suspension polymer of an aromatic vinyl-based monomer and a vinyl cyano-based monomer, and thus, the thermoplastic copolymer may include a derived unit from the aromatic vinyl-based monomer and a derived unit from the vinyl cyano-based monomer.

In particular, since the thermoplastic copolymer according to one embodiment of the present invention is prepared by the above-described preparation method, a significantly increased average particle diameter can be obtained when compared to a copolymer prepared by a conventional suspension polymerization method.

The thermoplastic copolymers are typically used in the industry after mixing with a rubbery polymer such as an acrylonitrile-butadiene-styrene copolymer. In the case where the materials to be mixed have similar particle diameters, roll mixing grindability may be excellent, and a product having excellent physical properties may be obtained. The thermoplastic copolymer according to the present invention has an increased average particle diameter when compared with a conventional thermoplastic copolymer, and may have a particle diameter similar to that of the rubbery polymer. Therefore, the thermoplastic copolymer can be mixed with a rubbery polymer, exhibits high roll mixing grindability, and has excellent industrial applicability.

In addition, the thermoplastic copolymer in the copolymer chain constituted by combining the derived unit of the aromatic vinyl-based monomer and the derived unit of the vinyl cyano-based monomer may have a structure in which the respective derived units are uniformly combined, and the yellow index may be low and the color property may be excellent.

Meanwhile, the "yellowness index" in the present invention can be obtained by manufacturing a test specimen for measuring physical properties with a thickness of 3mm, and measuring by the ASTM E313 method using a colorimeter (Color-Eye 7000A, GretaMacbeth Co.). In this case, the test specimens for measuring physical properties were prepared by mixing the thermoplastic copolymer of the present invention, the graft copolymer of Acrylonitrile (AN) -Butadiene (BD) -Styrene (SM) having a core-shell structure (AN: BD: SM ═ 13:60:27), and the bulk copolymer of styrene-acrylonitrile (containing 30 wt% of acrylonitrile) in a weight ratio of 10:30:60, pelletized using AN extruder, and then passed through AN injection molding machine. According to the results measured under the same conditions except that different thermoplastic copolymers used to manufacture the test specimens were used, the test specimens manufactured using the thermoplastic copolymer of the present invention exhibited better yellow index when compared to other test specimens. Thus, it can be found that the thermoplastic copolymer of the present invention has an improved yellow index.

In addition, the present invention provides a thermoplastic resin composition comprising the thermoplastic copolymer.

The thermoplastic resin composition according to an embodiment of the present invention is characterized by comprising the thermoplastic copolymer and an acrylonitrile-butadiene-styrene-based copolymer.

In addition, the thermoplastic resin composition includes two copolymers having the same degree of particle size as described above, and may have excellent roll mixing abrasiveness, and thus, may produce molded articles having excellent physical properties.

Meanwhile, the acrylonitrile-butadiene-styrene based copolymer plays a role of providing excellent moldability and impact resistance to the thermoplastic resin composition, and may be a graft copolymer having a core-shell structure, including: a core comprising units derived from conjugated diene monomers; and a shell surrounding the core and including a derived unit of an aromatic vinyl-based monomer and a derived unit of a vinyl cyano-based monomer.

In addition, the acrylonitrile-butadiene-styrene copolymer may be prepared by emulsion polymerization and emulsion graft polymerization, for example, by: a core (or seed) as a rubbery polymer is prepared by emulsion polymerization of a conjugated diene monomer, a vinyl cyano monomer and an aromatic vinyl monomer are injected into the core, and emulsion graft polymerization is performed.

Here, the average particle diameter of the core may be 0.1 to 0.6 μm, specifically, 0.2 to 0.5 μm, or 0.2 to 0.4 μm, and in this case, the copolymer including the core may have even better impact resistance and mechanical properties, and a molded article manufactured from the resin composition including the copolymer may have excellent impact resistance and gloss.

In addition, the acrylonitrile-butadiene-styrene copolymer may comprise: 30 to 70% by weight of a core comprising derived units of a conjugated diene monomer; and 30 to 70% by weight of a shell surrounding the core and comprising a derived unit of an aromatic vinyl-based monomer and a derived unit of a vinyl cyano-based monomer. In this case, the shell may include a derived unit of the aromatic vinyl-based monomer and a derived unit of the vinyl cyano-based monomer in a weight ratio of 7:3 to 8:2, and in this case, the impact resistance, mechanical properties, and moldability of the copolymer may be further more excellent.

Meanwhile, in one embodiment of the present invention, the resin composition may further include one or more additives selected from the group consisting of impact-reinforcing agents, lubricants, heat stabilizers, anti-dripping agents, antioxidants, light stabilizers, ultraviolet ray blockers, pigments, and inorganic fillers, in which case the additive may be used in an amount of 5 parts by weight or less, or 0.1 parts by weight to 1.0 parts by weight, based on 100 parts by weight of the copolymer.

In addition, specific materials of the additives are not particularly limited as long as they are used in the thermoplastic resin composition, and for example, the anti-dripping agent may be one or more selected from teflon, polyamide, polyorganosiloxane, Polytetrafluoroethylene (PTFE), and tetrafluoroethylene-hexafluoropropylene (TFE-HFP) copolymer, and the inorganic filler may use one or more selected from barium sulfate, barium glass filler, and barium oxide, in view of improvement of flame retardancy.

Hereinafter, embodiments of the present invention will be described in detail so that those skilled in the art can easily perform it. However, the present invention may be embodied in various different types and is not limited to the embodiments described below.

Preparation examples

120 parts by weight of ion-exchanged water, 100 parts by weight of styrene, 1.3 parts by weight of tricalcium phosphate, and 0.005 parts by weight of polyoxyethylene alkyl ether phosphate were mixed to prepare monomer droplets. In this case, the monomer droplets had an average particle diameter of 200 μm and contained 45% by weight of styrene.