KR20210112125A - Core-shell copolymer, method for preparing the same and polycarbonate based resin composition comprising the core-shell copolymer - Google Patents

Abstract

The present invention provides a core-shell copolymer and a method for preparing the same. The core-shell copolymer comprises: a core containing a repeating unit derived from a diene-based rubber monomer and a repeating unit derived from an aromatic vinyl-based monomer; and a graft shell surrounding the core and containing a repeating unit derived from an alkyl (meth)acrylate monomer and a repeating unit derived from an aromatic (alkyl)methacrylate monomer, wherein the refractive index of the core is 1.53 to 1.54, the refractive index of the shell is 1.55 to 1.56, the average particle diameter of the core is 100 to 150 nm, and the average particle diameter of the core-shell copolymer is 110 to 180 nm. According to the present invention, the impact resistance and blackness degree of a molded article prepared based on a resin composition comprising the core-shell copolymer can be improved.

Description

Core-shell copolymer, manufacturing method thereof, and polycarbonate-based resin composition comprising the same

The present invention relates to a core-shell copolymer, and more particularly, to a core-shell copolymer used as an impact modifier in a resin composition, a method for preparing the same, and a polycarbonate-based resin composition comprising the same.

Polycarbonate-based resins have excellent heat resistance, impact resistance and electrical properties, and are applied to various fields such as automobile parts and housings of electrical/electronic products, but have disadvantages such as poor moldability due to high melt viscosity and poor weather resistance.

Styrene-based resins such as acrylonitrile-butadiene-styrene (ABS) resin have excellent impact resistance, tensile strength, surface properties and processability, etc. It is difficult to apply to products that are deformed and require heat resistance.

Therefore, there are attempts to make a thermoplastic resin composition excellent in moldability, weather resistance, heat resistance, etc. by blending a polycarbonate resin and a styrene resin, but the compatibility between these resins is not sufficient, so the physical properties are not improved as expected, In particular, there is a problem of poor impact strength and colorability.

Meanwhile, methyl methacrylate-butadiene-styrene (MBS)-based impact modifiers are being applied to polycarbonate-based blend resins to improve impact resistance and inter-resin dispersibility. Polycarbonate-based blend resins are used as interior materials for automobiles, and to be used as interior and exterior materials for automobiles, they undergo a painting process to show excellent appearance.

Recently, the need for materials that can be used in a no-painting process for eco-friendliness and cost reduction is increasing. For unpainted materials, it is important to realize impact resistance, light resistance, scratch resistance, in particular, a deep black color. While light resistance and scratch resistance can be improved through UV clear coating, it is difficult to implement a deep black color.

KR 10-0666797 B

The problem to be solved in the present invention is to simultaneously control the particle diameter and refractive index of the core and the shell in the core-shell copolymer used as an impact modifier of the resin composition in order to solve the problems mentioned in the technology that is the background of the invention By doing, it aims to improve the impact resistance and blackness of the molded article prepared from the resin composition containing the core-shell copolymer.

According to one embodiment of the present invention for solving the above problems, the present invention provides a core containing a repeating unit derived from a diene-based rubber monomer and a repeating unit derived from an aromatic vinyl-based monomer; and a graft shell surrounding the core and containing a repeating unit derived from an alkyl (meth)acrylate monomer and a repeating unit derived from an aromatic (alkyl)methacrylate monomer, wherein the core has a refractive index of 1.53 to 1.54, and the refractive index of the shell is 1.55 to 1.56; The core has an average particle diameter of 100 to 150 nm, and the core-shell copolymer has an average particle diameter of 110 to 180 nm.

In addition, the present invention provides a method for producing a core-shell copolymer, comprising: preparing a seed by polymerizing a first core-forming monomer mixture including a diene-based rubber monomer and an aromatic vinyl-based monomer (S10); preparing a core by polymerizing a second core-forming monomer mixture including a diene-based rubber monomer and an aromatic vinyl-based monomer on the seed (S20); and adding a shell-forming monomer mixture including an alkyl (meth) acrylate monomer and an aromatic (alkyl) methacrylate monomer on the core and graft polymerization to prepare a core-shell copolymer (S30). and the refractive index of the core is 1.53 to 1.54, and the refractive index of the shell is 1.55 to 1.56; The core has an average particle diameter of 100 to 150 nm, and the core-shell copolymer has an average particle diameter of 110 to 180 nm.

In addition, the present invention provides a polycarbonate-based resin composition comprising the core-shell copolymer and the polycarbonate-based resin according to the present invention.

When the core-shell copolymer according to the present invention is used as an impact modifier for a resin composition, particularly a polycarbonate-based resin composition, a molded article formed from the polycarbonate-based resin composition including the same has excellent impact resistance and blackness.

The terms or words used in the description and claims of the present invention should not be construed as being limited to their ordinary or dictionary meanings, and the inventor should properly understand the concept of the term in order to best describe his invention. Based on the principle that can be defined, it should be interpreted as meaning and concept consistent with the technical idea of the present invention.

In the present invention, the term 'monomer-derived repeating unit' may refer to a component, structure, or material itself derived from a monomer, and refers to a repeating unit formed in the polymer by participating in the polymerization reaction during polymerization of the polymer. may be doing

In the present invention, the term 'copolymer' may mean including all copolymers formed by copolymerization of comonomers, and as a specific example, it is meant to include all of alternating copolymers, random copolymers and block copolymers. can

In the present invention, the term 'seed' supplements the mechanical properties of the core-shell copolymer, facilitates the polymerization of the core, and controls the average particle size of the core. It may mean a polymerized polymer, or a copolymer component.

In the present invention, the term 'core' refers to a rubber component in which a monomer forming the core or core layer of the core-shell type copolymer is polymerized, or a rubber polymer component or a rubber copolymer. It may mean a component, and a monomer forming the core is formed on the seed, and the core represents a shape surrounding the seed or a rubber component constituting the core or a core layer, or a rubber polymer component or It may mean a rubber copolymer component.

In the present invention, the term 'shell' refers to a polymer component forming a shell or a shell layer in which a monomer forming the shell of the core-shell type copolymer is graft-polymerized on the core, and enclosing the core, or a copolymer. (copolymer) may mean a component.

In the present invention, the term 'rubber' refers to a plastic material having elasticity, and may mean rubber, elastomer, or synthetic latex.

In the present invention, the term 'average particle diameter' refers to a weight average particle diameter (D50) measured according to an intensity Gaussian distribution by a dynamic laser light scattering method using Nicomp 380. can

In the present invention, the term 'refractive index' is an amount defined as the ratio of the speed of light c in vacuum to the phase velocity v in a certain medium (polymer or copolymer). It may mean that ethyl ketone is dissolved in a solvent mixed at 50:50 (volume%) and measured at room temperature using an ABE refractometer (ATAGO), a refractometer.

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

According to the present invention there is provided a core-shell copolymer. The core-shell copolymer according to the present invention comprises: a core containing a repeating unit derived from a diene-based rubber monomer and a repeating unit derived from an aromatic vinyl-based monomer; and a graft shell surrounding the core and containing a repeating unit derived from an alkyl (meth)acrylate monomer and a repeating unit derived from an aromatic (alkyl)methacrylate monomer, wherein the core has a refractive index of 1.53 to 1.54, and the shell of the refractive index is 1.55 to 1.56; The core may have an average particle diameter of 100 to 150 nm, and the core-shell copolymer may have an average particle diameter of 110 to 180 nm.

That is, in the core-shell copolymer according to the present invention, the refractive index and average particle diameter of the core and the shell are controlled within the above numerical ranges, so that the impact resistance of the molded article prepared from the resin composition comprising the same is improved and high blackness is expressed. It works.

According to an embodiment of the present invention, the diene-based rubber monomer forming the repeating unit derived from the diene-based rubber monomer included in the core in the core-shell copolymer according to the present invention is 1,3-butadiene, 2,3-dimethyl- It may include at least one selected from the group consisting of 1,3-butadiene, piperylene, 3-butyl-1,3-octadiene, isoprene, and 2-phenyl-1,3-butadiene. As a specific example, the diene-based rubber monomer may be 1,3-butadiene. In this case, there is an effect of improving the impact strength at room temperature of the molded article prepared from the resin composition including the core-shell copolymer.

According to one embodiment of the present invention, the aromatic vinyl-based monomer forming the repeating unit derived from the aromatic vinyl-based monomer included in the core is styrene, alphamethylstyrene, 3-methyl styrene, 4-methyl styrene, 4-propyl styrene, at least one selected from the group consisting of isopropenyl naphthalene, 1-vinyl naphthalene, styrene substituted with an alkyl group having 1 to 3 carbon atoms, 4-cyclohexyl styrene, 4-(p-methylphenyl) styrene, and styrene substituted with halogen; may include As a specific example, the aromatic vinyl monomer may be styrene. In this case, the molded article prepared from the resin composition including the core-shell copolymer has the effect of improving impact strength and thermal stability at room temperature.

According to an embodiment of the present invention, the core may further include a repeating unit derived from a crosslinkable monomer, in addition to the repeating unit derived from the diene-based rubber monomer and the repeating unit derived from the aromatic vinyl-based monomer, in this case, including core polymerization, When the shell is formed by grafting, there is an effect of improving polymerization reactivity. The crosslinkable monomer is ethylene glycol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, allyl (meth)acrylate, trimethylolpropane tri(meth)acrylate and pentaerythritol tetra(meth) ) (meth)acrylic crosslinkable monomers such as acrylates; and at least one selected from the group consisting of vinyl-based cross-linkable monomers such as divinylbenzene, divinyl naphthalene and diallyl phthalate.

According to an embodiment of the present invention, the content of the core may be 50 to 70 parts by weight, 50 to 65 parts by weight, or 50 to 60 parts by weight based on 100 parts by weight of the total core-shell copolymer. By increasing the core content in the core-shell copolymer within the above range, the molded article made of the resin composition including the core-shell copolymer has an effect of improving impact strength and excellent gloss.

According to an embodiment of the present invention, the content of the repeating unit derived from the diene-based rubber monomer included in the core is 70 to 80% by weight, 70 to 78% by weight, or 70 to 75% by weight, based on the total content of the core. may be, and the content of the repeating unit derived from the aromatic vinyl-based monomer included in the core may be 20 to 30% by weight, 20 to 28% by weight, or 20 to 25% by weight based on the total content of the core. In forming the core, the refractive index of the core may be controlled to 1.53 to 1.54 by including the repeating unit derived from the diene-based rubber monomer and the repeating unit derived from the aromatic vinyl-based monomer in an amount within the above range. In addition, compatibility may be imparted between the core and the thermoplastic resin within the refractive index range of the core.

According to an embodiment of the present invention, the core may include a seed containing a repeating unit derived from a diene-based rubber monomer and a repeating unit derived from an aromatic vinyl-based monomer to control the average particle diameter of the core. may be a core surrounding the seed.

The repeating unit derived from the diene-based rubber monomer and the repeating unit derived from the aromatic vinyl-based monomer included in the seed may be the same as the type of each monomer for forming the repeating unit derived from the monomer included in the core described above.

When the core includes seeds, the content of the seeds may be from 10 to 40% by weight, from 10 to 38% by weight, or from 10 to 35% by weight, based on the total content of the core, within this range the average of the cores The particle size can be easily adjusted.

In addition, when the core includes a seed, the content of the repeating unit derived from the diene-based rubber monomer included in the core may include the content of the repeating unit derived from the diene-based rubber monomer included in the seed, and the core contains the repeating unit derived from the diene-based rubber monomer. The content of the repeating unit derived from the aromatic vinyl-based monomer included may include the content of the repeating unit derived from the aromatic vinyl-based monomer included in the seed.

According to an embodiment of the present invention, the average particle diameter of the core may be 100 to 150 nm. The average particle diameter of the core is controlled to a desired size by controlling the input amount of the emulsifier used in the step (S10) of preparing the seed in the method for producing a core-shell copolymer, which will be described later. It can be controlled by adjusting the weight ratio of the monomer mixture for forming the first core used in the preparing step (S10) and the monomer mixture for forming the second core used in the step (S20) of preparing the core.

In the present invention, as described above, the average particle diameter of the core can be controlled to 100 to 150 nm, and compatibility can be imparted between the core and the thermoplastic resin within the range of the average particle diameter of the core, and the impact strength at room temperature and Both low-temperature impact strength have excellent effects.

According to an embodiment of the present invention, the alkyl (meth) acrylate monomer forming the repeating unit derived from the alkyl (meth) acrylate monomer included in the shell in the core-shell copolymer according to the present invention is an alkyl having 1 to 8 carbon atoms. It may be a (meth)acrylate monomer, and in this case, it may be meant to include both a linear alkyl group having 1 to 8 carbon atoms and a branched alkyl group having 3 to 8 carbon atoms. As a specific example, the alkyl (meth) acrylate monomer is methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, pentyl (meth) acrylate, hexyl (meth) ) acrylate, heptyl (meth) acrylate, octyl (meth) acrylate and 2-ethylhexyl (meth) acrylate may be at least one selected from the group consisting of acrylate. As a more specific example, the alkyl (meth)acrylate monomer may be methyl methacrylate. In this case, there is an effect of improving the impact strength at room temperature of the molded article prepared from the resin composition including the core-shell copolymer.

According to an embodiment of the present invention, the aromatic (alkyl) methacrylate monomer forming the repeating unit derived from the aromatic (alkyl) methacrylate monomer included in the shell is benzyl methacrylate, phenyl methacrylate, 9-anthra It may include at least one selected from the group consisting of cenyl methyl methacrylate, ethylene glycol phenyl ether methacrylate, 1-naphthyl methacrylate, and 2-naphthyl methacrylate. As a specific example, the aromatic (alkyl) methacrylate monomer may be benzyl methacrylate. In this case, the particle dispersibility of the core-shell copolymer on the resin composition containing the core-shell copolymer is excellent, and the low-temperature impact strength of the molded article prepared from the resin composition containing the core-shell copolymer is improved. .

According to an embodiment of the present invention, the content of the shell may be 30 to 50 parts by weight, 35 to 50 parts by weight, or 40 to 50 parts by weight based on 100 parts by weight of the total core-shell copolymer. Within this range, there is an effect of simultaneously improving the processability of the resin composition including the core-shell copolymer and the impact strength of the molded article prepared therefrom.

According to an embodiment of the present invention, the content of the repeating unit derived from the alkyl (meth)acrylate monomer included in the shell is 1 to 10 parts by weight, 2 to 8 parts by weight, based on 100 parts by weight of the total core-shell copolymer. parts, or 3 to 7 parts by weight, and the content of the repeating unit derived from the aromatic (alkyl) methacrylate monomer included in the shell is 25 to 40 parts by weight, 30 to 40 parts by weight, based on 100 parts by weight of the total core-shell copolymer. 38 parts by weight, or 30 to 35 parts by weight. In forming the shell, by including the repeating unit derived from the alkyl (meth) acrylate monomer and the repeating unit derived from the aromatic (alkyl) methacrylate monomer in an amount within the above range, the refractive index of the shell can be controlled to 1.55 to 1.56 . In addition, by forming a structure sufficiently surrounding the core within the refractive index range of the shell, it is possible to simultaneously improve the impact strength and thermal stability of the molded article molded from the resin composition including the core-shell copolymer.

According to an embodiment of the present invention, the average particle diameter of the core-shell copolymer may be 110 to 180 nm. The average particle diameter of the core-shell copolymer may be controlled according to the average particle diameter of the core particles and the content ratio of the core to the shell. Specifically, as described above, while controlling the average particle diameter of the core to 100 to 150 nm, the content of the core is 50 to 70 parts by weight and the content of the shell is 30 based on 100 parts by weight of the total core-shell copolymer. By adjusting to 50 parts by weight, the average particle diameter of the core-shell copolymer can be controlled to 110 to 180 nm. In addition, within the average particle diameter range of the core-shell copolymer, a molded article prepared from the resin composition including the same has an effect of improving impact strength and excellent gloss.

According to one embodiment of the present invention, the present invention provides a manufacturing method for preparing the core-shell copolymer according to the present invention. In the method for preparing a core-shell copolymer according to the present invention, a seed is prepared by polymerizing a first core-forming monomer mixture including a diene-based rubber monomer and an aromatic vinyl-based monomer in the method for preparing a core-shell copolymer. to (S10); preparing a core by polymerizing a second core-forming monomer mixture including a diene-based rubber monomer and an aromatic vinyl-based monomer on the seed (S20); and adding a shell-forming monomer mixture including an alkyl (meth) acrylate monomer and an aromatic (alkyl) methacrylate monomer on the core and graft polymerization to prepare a core-shell copolymer (S30). and the refractive index of the core is 1.53 to 1.54, and the refractive index of the shell is 1.55 to 1.56; The core may have an average particle diameter of 100 to 150 nm, and the core-shell copolymer may have an average particle diameter of 110 to 180 nm.

The step of preparing the seed facilitates polymerization of the core and controls the average particle diameter of the core during polymerization of the core-shell copolymer, and the first core-forming monomer mixture includes the diene-based rubber monomer and the aromatic It may include a vinyl-based monomer, and may further include a cross-linkable monomer if necessary, and the type and content of the monomer input to form the seed is the above-described repeating unit derived from the diene-based rubber monomer and the aromatic It may be the same as the type and content of the monomer for forming the vinyl-based monomer-derived repeating unit.

According to an embodiment of the present invention, the step of preparing the core is a step for polymerizing a core polymer surrounding the seed on the previously prepared seed, and the second core-forming monomer mixture is the diene-based rubber monomer. and an aromatic vinyl-based monomer, and may further include a cross-linkable monomer if necessary, and the type and content of the monomer input to form the core is a repeating unit derived from the aforementioned diene-based rubber monomer. And it may be the same as the type and content of the monomer for forming the repeating unit derived from the aromatic vinyl-based monomer.

According to one embodiment of the present invention, the step of preparing the core-shell copolymer is a step for polymerizing a graft shell surrounding the core on the previously prepared core, and the monomer mixture for forming the shell is the alkyl It may include a (meth) acrylate monomer and an aromatic (alkyl) methacrylate, and may further include a cross-linkable monomer if necessary, and the type and content of the monomer forming the graft shell is described above. It may be the same as the type and content of the monomer for forming the repeating unit derived from one alkyl (meth)acrylate monomer and the repeating unit derived from the aromatic (alkyl)methacrylate.

According to an embodiment of the present invention, as described above, the refractive index of the core may be controlled by adjusting the content of the diene-based rubber monomer and the aromatic vinyl-based monomer included in the core. As a specific example, the total amount of the diene-based rubber monomer input in the step of preparing the seed (S10) and the step of preparing the core (S20) is based on the total content of the monomer mixture for forming the first and second cores. 70 to 80% by weight, 70 to 78% by weight, or 70 to 75% by weight, and the total amount of the aromatic vinyl-based monomer is 20 to 30 based on the total content of the first and second core-forming monomer mixtures By adjusting the weight %, 20 to 28 weight %, or 20 to 35 weight %, the refractive index of the core can be controlled to 1.53 to 1.54.

According to an embodiment of the present invention, as described above, the average particle diameter of the core is controlled to a desired size by adjusting the input amount of the emulsifier used in the step S10 of preparing the seed, and at the same time, It can be controlled by adjusting the weight ratio of the monomer mixture for forming the first core used in the step of preparing the seed (S10) and the monomer mixture for forming the second core used in the step of preparing the core (S20). Specifically, even if the content of the monomer input in the step of preparing the seed (S10) is changed, the average particle diameter of the seed can be controlled to a desired size by adjusting the input amount of the emulsifier. For example, if the input amount of the emulsifier is increased during seed preparation, the average particle diameter of the seed may be reduced.

According to an embodiment of the present invention, in the step of preparing the seed (S10), the input amount of the emulsifier is adjusted to 0.3 to 0.5 parts by weight based on 100 parts by weight of the total of 100 parts by weight of the monomer mixture for forming the first core, and at the same time, the step of preparing the seed ( The content of the seed input in S10) is adjusted to 10 to 40% by weight, 10 to 38% by weight, or 10 to 35% by weight, based on the total content of the core, and used in the step of preparing the core (S20) By adjusting the monomer mixture for forming the second core to 60 to 90 wt%, 62 to 90 wt%, or 65 to 90 wt%, based on the total content of the core, the average particle diameter of the core can be controlled to 100 to 150 nm. can

According to an embodiment of the present invention, as described above, the refractive index of the shell can be controlled by adjusting the content of the alkyl (meth) acrylate monomer and the aromatic (alkyl) methacrylate monomer included in the shell. As a specific example, in the step of preparing the core-shell copolymer (S30), the amount of the alkyl (meth)acrylate monomer is 1 to 10 parts by weight, 2 to 8 parts by weight based on 100 parts by weight of the total core-shell copolymer. parts, or 3 to 7 parts by weight, and the amount of the aromatic (alkyl) methacrylate monomer added is 25 to 40 parts by weight, 30 to 38 parts by weight, or 30 to 35 parts by weight based on 100 parts by weight of the total core-shell copolymer By adjusting to parts by weight, the refractive index of the shell can be controlled to be 1.55 to 1.56.

According to an embodiment of the present invention, as described above, the average particle diameter of the core-shell copolymer may be controlled by adjusting the average particle diameter of the core particles and the content ratio of the core to the shell. As a specific example, the average particle diameter of the core is controlled to 110 to 150 nm through the steps (S10) and (S20), and the content of the core is 50 to 70 parts by weight based on 100 parts by weight of the total core-shell copolymer. , by adding the monomer so that the content of the shell is 30 to 50 parts by weight, the average particle diameter of the core-shell copolymer can be controlled to 110 to 180 nm.

According to an embodiment of the present invention, the polymerization of preparing the seed, preparing the core, and preparing the core-shell copolymer may be carried out at a temperature of 50 to 150 ℃ or 50 to 100 ℃, , it can be carried out in the presence of various solvents and additives commonly used to carry out the polymerization of each step.

For example, the step of preparing the seed, the step of preparing the core, and the step of preparing the core-shell copolymer may each independently be carried out using methods such as emulsion polymerization, bulk polymerization, suspension polymerization, solution polymerization, etc. and further using additives such as an initiator, an emulsifier, a polymerization terminator, ion-exchanged water, a molecular weight regulator, an activator, and a redox catalyst, it can be carried out by an emulsion polymerization method such as a batch type, semi-batch type, continuous type, etc. .

The initiator may include, for example, inorganic peroxides such as sodium persulfate, potassium persulfate, ammonium persulfate, potassium perphosphate, and hydrogen peroxide; Diisopropylbenzene hydroperoxide, t-butyl hydroperoxide, cumene hydroperoxide, p-mentane hydroperoxide, di-t-butyl peroxide, t-butylcumyl peroxide, acetyl peroxide, isobutyl peroxide , organic peroxides such as octanoyl peroxide, benzoyl peroxide, 3,5,5-trimethylhexanol peroxide, and t-butyl peroxy isobutylate; nitrogen compounds such as azobis isobutyronitrile, azobis-2,4-dimethylvaleronitrile, azobiscyclohexanecarbonitrile, and azobisisobutyronitrile (butyric acid)methyl. These polymerization initiators can be used individually or in combination of 2 or more types. The initiator may be used in an amount of 0.005 parts by weight to 0.2 parts by weight based on 100 parts by weight of the total seed or 100 parts by weight of the core-shell copolymer.

Meanwhile, an organic peroxide or inorganic peroxide initiator may be used as a redox-based polymerization initiator in combination with a reducing agent. The reducing agent is not particularly limited, but a compound containing a metal ion in a reduced state such as ferrous sulfate and cuprous naphthenate; a sulfonic acid compound such as sodium methanesulfonate; an amine compound such as dimethylaniline; can These reducing agents can be used individually or in combination of 2 or more types. The reducing agent may be used in an amount of 0.005 parts by weight to 20 parts by weight based on 1 part by weight of the peroxide.

The emulsifier may be at least one selected from the group consisting of anionic emulsifiers, cationic emulsifiers and nonionic emulsifiers, and specific examples include polyoxyethylene alkyl ether, polyoxyethylene alkylphenol ether, polyoxyethylene alkyl ester, poly Nonionic emulsifiers such as oxyethylene sorbitan alkyl esters; salts of fatty acids such as myristic acid, palmitic acid, oleic acid, and linolenic acid; alkyl benzene sulfonates such as sodium dodecyl benzene sulfonate; Anionic emulsifiers such as succinate; Cationic emulsifiers such as alkyl trimethyl ammonium chloride, dialkylammonium chloride, benzyl ammonium chloride; sulfo esters of α,β-unsaturated carboxylic acids, sulfate esters of α,β-unsaturated carboxylic acids and copolymerizable emulsifiers such as sulfoalkyl aryl ether. Especially, an anionic emulsifier is used suitably. The emulsifier may be used in an amount of 0.1 to 10 parts by weight based on 100 parts by weight of the seed or 100 parts by weight of the core-shell copolymer.

Water may be used as the ion-exchange water, and the ion-exchange water may be used in an amount of 100 parts by weight to 400 parts by weight based on 100 parts by weight of the monomer mixture.

The molecular weight modifier may include, for example, mercaptans such as α-methylstyrene dimer, t-dodecyl mercaptan, n-dodecyl mercaptan, and octyl mercaptan; halogenated hydrocarbons such as carbon tetrachloride, methylene chloride and methylene bromide; and sulfur-containing compounds such as tetraethyl diuram disulfide, dipentamethylene diuram disulfide, and diisopropyl xanthogen disulfide. The molecular weight modifier may be used in an amount of 0.1 to 3 parts by weight based on 100 parts by weight of the seed or 100 parts by weight of the core-shell copolymer.

The activator may be, for example, at least one selected from sodium hydrosulfite, sodium formaldehyde sulfoxylate, sodium ethylenediaminetetraacetate, ferrous sulfate, lactose, dextrose, sodium linoleate, and sodium sulfate. The activator may be used in an amount of 0.01 parts by weight to 0.15 parts by weight based on 100 parts by weight of the total seed or 100 parts by weight of the core-shell copolymer.

The redox catalyst may be, for example, sodium formaldehyde sulfoxylate, ferrous sulfate, disodium ethylenediamine tetraacetate, cupric sulfate, or the like. The redox catalyst may be used in an amount of 0.01 parts by weight to 0.1 parts by weight based on 100 parts by weight of the total seed or 100 parts by weight of the core-shell copolymer.

In addition, according to an embodiment of the present invention, the core polymer and the core-shell copolymer prepared in the step of preparing the core and the step of preparing the core-shell are of latex in which the polymer and the copolymer are dispersed in a solvent, respectively. After preparing the core-shell copolymer latex in the step of preparing the core-shell polymer, agglomeration to obtain a core-shell copolymer composition comprising the core-shell copolymer in the form of powder , aging, dehydration and drying may be performed.

According to one embodiment of the present invention, the present invention provides a resin composition comprising the core-shell copolymer according to the present invention as an impact modifier. The resin composition may include a core-shell copolymer and a polycarbonate-based resin. That is, the resin composition may be a polycarbonate-based resin composition.

According to an embodiment of the present invention, the polycarbonate-based resin may be included in an amount of 50 to 99 parts by weight, 60 to 90 parts by weight, or 70 to 80 parts by weight, based on 100 parts by weight of the total polycarbonate-based resin composition, Within the range, there is an effect of improving the thermal stability of the molded article prepared from the polycarbonate-based resin composition.

According to an embodiment of the present invention, the core-shell copolymer may be included in an amount of 1 to 10 parts by weight, 1 to 8 parts by weight, or 1 to 5 parts by weight based on 100 parts by weight of the total polycarbonate-based resin composition, Within this range, there is an effect of improving compatibility between resins on the blend resin composition including the core-shell copolymer.

According to an embodiment of the present invention, the polycarbonate-based resin composition according to the present invention may further include an acrylonitrile-butadiene-styrene (ABS) resin, and the ABS resin is 100 of the polycarbonate-based resin composition. It may be included in 1 to 40 parts by weight, 10 to 35 parts by weight, or 20 to 30 parts by weight based on parts by weight, and within this range, the moldability and weather resistance of the molded article prepared from the polycarbonate-based resin composition are improved. have.

According to one embodiment of the present invention, the polycarbonate-based resin composition according to the present invention, in addition to the core-shell copolymer and the polycarbonate-based polymer, a stabilizer, processing, if necessary, within a range that does not reduce its physical properties Additives such as auxiliary agents, heat stabilizers, lubricants, pigments, dyes, and antioxidants may be further included, and these additives may be included in an amount of 60 parts by weight or less based on 100 parts by weight of the total polycarbonate-based resin composition.

In addition, the polycarbonate-based resin may take the form of a linear polycarbonate resin, a branched polycarbonate resin, or a polyester carbonate copolymer resin, and the polycarbonate resin included in the polycarbonate-based resin composition is limited to a specific form. All of these linear polycarbonate resins, branched polycarbonate resins or polyester carbonate copolymer resins may be used.

Of these, as the linear polycarbonate resin, for example, a bisphenol A-based polycarbonate resin may be used, and as the branched polycarbonate resin, for example, a polyfunctionality such as trimellitic anhydride or trimellitic acid One prepared by reacting an aromatic compound with a dihydric phenol-based compound and a carbonate precursor may be used. In addition, as the polyester carbonate copolymer resin, for example, one prepared by reacting a difunctional carboxylic acid with a dihydric phenol and a carbonate precursor may be used. In addition, conventional linear polycarbonate resins, branched polycarbonate resins, or polyester carbonate copolymer resins may be used without limitation.

According to an embodiment of the present invention, a polycarbonate-based resin composition is prepared by mixing each component described above, and the polycarbonate-based resin composition is melt-extruded in an extruder. It is possible to manufacture a thermoplastic resin or a plastic molded article made therefrom.

According to one embodiment of the present invention, the present invention provides a plastic molded article prepared from the polycarbonate-based resin composition according to the present invention. This plastic molded article includes a resin substrate in which a polycarbonate-based resin is bonded to form a resin matrix, and with it, the core-shell copolymer according to the present invention uniformly dispersed in the resin matrix is included, so that the impact at room temperature The strength and low-temperature impact strength are improved, and at the same time, high blackness is expressed.

Therefore, these plastic molded articles are excellent in impact resistance and blackness, and can be preferably used from various electric/electronic products or automobile parts to lenses or glass windows. In particular, it can be used as unpainted interior and exterior materials for automobiles requiring high blackness color.

Hereinafter, the present invention will be described in more detail by way of Examples. However, the following examples are intended to illustrate the present invention, and it is clear to those skilled in the art that various changes and modifications are possible within the scope and spirit of the present invention, and the scope of the present invention is not limited thereto.

< Example >

Example One

<Preparation of core-shell copolymer>

(1) seed preparation

In a high-pressure polymerization reactor substituted with nitrogen, 30 parts by weight of ion-exchanged water, 0.1 parts by weight of sodium sulfate, 0.5 parts by weight of potassium oleate, 0.005 parts by weight of ferrous sulfide, 0.01 parts by weight of sodium ethylenediaminetetraacetate, 0.025 parts by weight of sodium formaldehyde sulfoxylate 0.04 parts by weight of diisopropylbenzene hydroperoxide was added. Here, based on the total content of the core, a monomer mixture for forming the first core containing 14 wt% of 1,3-butadiene and 5 wt% of styrene was added at once, and polymerization was started at a reaction temperature of 60 °C for 10 hours. , butadiene-styrene seeds having an average particle diameter of 80 nm were prepared.

(2) Core manufacturing

In a nitrogen-substituted high-pressure polymerization reactor, 100 parts by weight of ion-exchanged water, 0.95 parts by weight of potassium oleate, 0.1 parts by weight of sodium formaldehyde sulfoxylate, 0.05 parts by weight of diisopropylbenzene hydroperoxide, 0.1 parts by weight of sodium ethylenediaminetetraacetate , 0.19 parts by weight of ferrous sulfate, and a monomer mixture for forming a second core comprising 61% by weight of 1,3-butadiene and 20% by weight of styrene, based on the total content of the core, and the obtained seed 19% by weight (based on solid content) was added in a batch, and polymerization was performed at a reaction temperature of 70 °C. Thereafter, the polymerization reaction was terminated when the polymerization conversion rate reached 95%, and a butadiene-styrene rubber latex having an average particle diameter of butadiene-styrene rubber of 130 nm was prepared. At this time, the time required for polymerization was 23 hours.

(3) Core-shell copolymer preparation

In a high-pressure polymerization reactor substituted with nitrogen, 5 parts by weight of methyl methacrylate, 5 parts by weight of benzyl to 60 parts by weight (based on solid content) of the butadiene-styrene rubber latex (core) obtained above based on 100 parts by weight of the total core-shell copolymer 35 parts by weight of methacrylate, 200 parts by weight of ion-exchanged water, 0.20 parts by weight of potassium oleate, 0.05 parts by weight of sodium formaldehyde sulfoxylate, 0.05 parts by weight of sodium ethylenediaminetetraacetate, 0.009 parts by weight of ferrous sulfate and t-butyl 0.07 parts by weight of hydroperoxide was added at once, and graft polymerization was initiated at a reaction temperature of 60°C. Thereafter, the polymerization reaction was terminated when the polymerization conversion rate reached 98%, and a core-shell copolymer latex having an average particle diameter of 155 nm was prepared. At this time, the time required for polymerization was 2 hours.

<Preparation of core-shell copolymer powder>

After diluting the obtained latex containing the core-shell copolymer in distilled water to 15% by weight based on the solid content, it was placed in a coagulation tank, and the temperature inside the coagulation tank was increased to 70 °C. After that, 4 parts by weight of a calcium chloride solution is added to the latex containing the core-shell copolymer based on 100 parts by weight of the solid content, and agglomerated while stirring, after which the copolymer and water are separated, dehydrated and dried to core- A shell copolymer powder was obtained.

Example 2

In Example 1, the preparation of the core-shell copolymer was carried out in the same manner as in Example 1, except that 35 parts by weight of phenyl methacrylate was added instead of 35 parts by weight of benzyl methacrylate.

Example 3

In Example 1, when preparing seeds, 1,3-butadiene was added in an amount of 26 wt% instead of 14 wt%, styrene in an amount of 9 wt% instead of 5 wt%, and in an amount of 0.7 parts by weight instead of 0.5 parts by weight of potassium oleate used as an emulsifier, and the core By adding 49 wt% instead of 61 wt% of 1,3-butadiene, and 16 wt% instead of 20 wt% of styrene, 35 wt% of seeds were added instead of 19 wt% based on the total content of the core. It was carried out in the same manner as in Example 1.

Example 4

In Example 1, when preparing seeds, 1,3-butadiene was added at 10 wt% instead of 14 wt%, styrene at 3 wt% instead of 5 wt%, and 0.3 wt% instead of 0.5 wt% of potassium oleate used as an emulsifier, and the core When preparing 1,3-butadiene at 65% by weight instead of 61% by weight and styrene at 22% by weight instead of 20% by weight, 13% by weight was added instead of 19% by weight of seeds based on the total content of the core. It was carried out in the same manner as in Example 1.

comparative example One

In Example 1, when preparing the core-shell copolymer, 35 parts by weight instead of 5 parts by weight of methyl methacrylate and 5 parts by weight of styrene instead of 35 parts by weight of benzyl methacrylate were added in the same manner as in Example 1 method was carried out.

comparative example 2

In Example 1, in the preparation of the core-shell copolymer, 35 parts by weight of styrene was added instead of 35 parts by weight of benzyl methacrylate, and the same method as in Example 1 was performed.

comparative example 3

In Example 1, when preparing the core-shell copolymer, 12 parts by weight instead of 5 parts by weight of methyl methacrylate and 28 parts by weight of styrene instead of 35 parts by weight of benzyl methacrylate were added. method was carried out.

comparative example 4

In Example 1, the preparation of the core-shell copolymer was carried out in the same manner as in Example 1, except that 35 parts by weight of cyclohexyl methacrylate was added instead of 35 parts by weight of benzyl methacrylate.

comparative example 5

In Example 1, when preparing seeds, 1,3-butadiene was added at 75 wt% instead of 14 wt%, styrene at 25 wt% instead of 5 wt%, and at 0.7 parts by weight instead of 0.5 parts by weight of potassium oleate used as an emulsifier, butadiene- It was carried out in the same manner as in Example 1, except that styrene rubber latex was prepared and the core manufacturing step of step 2 was not performed.

comparative example 6

In Example 1, when preparing seeds, 1,3-butadiene was added at 6 wt% instead of 14 wt%, styrene at 2 wt% instead of 5 wt%, and at 0.1 wt% instead of 0.5 wt% of potassium oleate used as an emulsifier, and the core By adding 69% by weight instead of 61% by weight of 1,3-butadiene and 23% by weight instead of 20% by weight of styrene during preparation, 8% by weight was added instead of 19% by weight of seeds based on the total content of the core. It was carried out in the same manner as in Example 1.

comparative example 7

In Example 1, 1,3-butadiene was added at 19% by weight instead of 15% by weight when preparing the seed, and when preparing the core, 81% by weight instead of 61% by weight of 1,3-butadiene was added, and styrene was not added. was carried out in the same manner as in Example 1.

< Experimental example >

Experimental example One

The average particle diameter and refractive index of each of the core and core-shell copolymers prepared in Examples 1 to 4 and Comparative Examples 1 to 7 were measured as follows, and the composition of each core-shell copolymer together with the results was measured It is shown in Tables 1 and 2 below.

* Average particle diameter (D50, nm): After preparing a sample obtained by diluting each of the prepared rubber latex including the core and the prepared core-shell copolymer to 200 ppm or less, Nicomp at room temperature (23 ℃) 380, the average particle diameter (D50) of the rubber particles dispersed in the rubber latex according to the intensity Gaussian distribution by a dynamic laser light scattering method was measured.

* Refractive index: The core and core-shell copolymer refractive indices were measured using an ABE refractometer. In addition, the shell refractive index was derived by measuring the core refractive index and the core-shell copolymer refractive index, and then calculating based on the weight ratio of the core and the shell in the core-shell. As a specific example, when the core-shell copolymer in the core-shell copolymer has a weight ratio of 6:4 and the refractive index of the core-shell copolymer is 1.545 and the refractive index of the core is 1.535, the refractive index A of the shell is derived according to Equation 1 below. . In Equation 1 below, A may be derived as 1.560.

[Equation 1]

1.545 = (0.6 x 1.535) + (0.4 x A)

division Example One 2 3 4 core BD ¹⁾ content (wt%) 75 75 75 75 SM ²⁾ content (wt%) 25 25 25 25 Average particle size (nm) 130 130 100 150 core refractive index 1.535 1.535 1.535 1.535 Core content (parts by weight) 60 60 60 60 shell MMA ^{3 )} content (parts by weight) 5 5 5 5 Aromatic (alkyl) methacrylate content (parts by weight) BzMA ^{4 )} 35 - 35 35 PhMA ^{5 )} - 35 - - CHMA ^{6 )} content (parts by weight) - - - - SM ⁸⁾ content (parts by weight) - - - - shell refractive index 1.560 1.560 1.560 1.560 Core-shell (MBS) average particle size (nm) 155 153 118 175 Core-shell (MBS) refractive index 1.545 1.545 1.545 1.545 1) BD: 1,3-butadiene
2) SM: Styrene
3) MMA: methyl methacrylate
4) BzMA: benzyl methacrylate
5) PhMA: Phenyl Methacrylate
6) CHMA: cyclohexyl methacrylate
7) SM: Styrene

division comparative example One 2 3 4 5 6 7 core BD ¹⁾ content (wt%) 75 75 75 75 75 75 100 SM ²⁾ content (wt%) 25 25 25 25 25 25 0 Average particle size (nm) 130 130 130 130 80 180 130 core refractive index 1.535 1.535 1.535 1.535 1.535 1.535 1.517 Core content (parts by weight) 60 60 60 60 60 60 60 shell MMA ^{3 )} content (parts by weight) 35 5 12 5 5 5 5 Aromatic (alkyl) methacrylate content (parts by weight) BzMA ^{5 )} - - - - 35 35 35 PhMA ^{6 )} - - - - - - - CHMA ^{7 )} content (parts by weight) - - - 35 - - - SM ⁸⁾ content (parts by weight) 5 35 28 - - - - shell refractive index 1.500 1.580 1.560 1.505 1.560 1.560 1.557 Core-shell (MBS) average particle size (nm) 155 152 152 154 95 213 155 Core-shell (MBS) refractive index 1.521 1.553 1.545 1.523 1.545 1.545 1.533 1) BD: 1,3-butadiene
2) SM: Styrene
3) MMA: methyl methacrylate
4) BzMA: benzyl methacrylate
5) PhMA: Phenyl Methacrylate
6) CHMA: cyclohexyl methacrylate
7) SM: Styrene

Experimental example 2

In order to evaluate the impact strength and blackness of the molded article molded from the polycarbonate-based resin composition comprising the core-shell copolymer prepared in Examples 1 to 4 and Comparative Examples 1 to 7 as an impact modifier, the following method was used. Polycarbonate-based resin composition specimens were prepared and evaluated, and are shown in Tables 3 and 4.

<Preparation of polycarbonate-based resin composition specimen>

Based on 100 parts by weight of the polycarbonate-based resin composition, 5 parts by weight of the core-shell copolymer powder prepared in Examples and Comparative Examples, acrylonitrile-butadiene-styrene (ABS) copolymer powder (DP270, manufactured by LG Chem) 8 parts by weight, SAN resin (SAN 81HF, manufactured by LG Chem) 17 parts by weight, polycarbonate-based resin (Lupoy 1300-15, manufactured by LG Chem) 70 parts by weight, lubricant and antioxidant, and using a twin-screw extruder at 200 °C was melted and kneaded to obtain pellets. The obtained pellets were subjected to T-die extrusion at a die temperature of 220° C. to prepare each specimen having a thickness of 1/8″ inch. The following physical properties were measured for each specimen, and the results are shown in Tables 3 and 4.

* Izod impact strength: 1/8" inch notch specimen was evaluated by the ASTM D256 test method. At this time, measurements were made in both chambers maintained at room temperature (23 ℃) and low temperature (-30 ℃), and in each chamber. After aging 1/8" inch notch specimens for 6 hours, the specimens were taken out and evaluated by the ASTM D256 test method.

* Blackness: L* value was measured by CIE LabMethod. As a measuring device, X-rite's Color-eye 7000A was used.

division Example One 2 3 4 Composition of the resin composition polycarbonate resin
(parts by weight) 70 70 70 70 ABS copolymer
(parts by weight) 25 25 25 25 Core-shell copolymer (parts by weight) 5 5 5 5 Room temperature impact strength (1/8") (23 °C, kgf m/m) 70 69 63 71 Low temperature impact strength (1/8") (-30 ℃, kgf m/m) 19 13 19 21 blackness (L)*(SCE) 4.2 4.1 4.0 4.5 * The lower the blackness (L) value, the higher the blackness

division comparative example One 2 3 4 5 6 7 Composition of the resin composition polycarbonate resin
(parts by weight) 70 70 70 70 70 70 70 ABS copolymer
(parts by weight) 25 25 25 25 25 25 25 Core-shell copolymer (parts by weight) 5 5 5 5 5 5 5 Room temperature impact strength (1/8") (23 °C, kgf m/m) 69 69 68 68 58 72 73 Low temperature impact strength (1/8") (-30 ℃, kgf m/m) 20 16 17 19 6 23 26 blackness (L)*(SCE) 8.3 13.2 10.8 9.0 5.8 8.8 8.0 * The lower the blackness (L) value, the higher the blackness

Referring to Table 3 above, Examples 1 to 4, in which the average particle diameter and refractive index of each of the core and shell in the core-shell copolymer according to the present invention have appropriate ranges, have excellent both room temperature impact strength and low temperature impact strength, and It can be seen that high blackness is exhibited. In particular, Examples 1, 3 and 4 using benzyl methacrylate as an aromatic (alkyl) methacrylate among the monomers for forming a shell compared to Example 2 using phenyl methacrylate as an aromatic (alkyl) methacrylate It can be confirmed that it exhibits excellent low-temperature impact strength.

On the other hand, referring to Table 4, in comparison to using styrene or cyclohexyl methacrylate instead of aromatic (alkyl) methacrylate as a monomer for forming a shell, 1 to 4 showed insignificant blackness improvement effect, which can be confirmed in Examples. No improvement could be expected.

In addition, it can be seen that Comparative Example 5, in which the average particle diameter of the core and core-shell copolymer is smaller than the appropriate range, is disadvantageous in both room temperature impact strength and low temperature impact strength, and the average particle diameter of the core and core-shell copolymer is less than the appropriate range. In Comparative Example 6, the effect of improving blackness was insignificant, and Comparative Example 7, which did not contain styrene as a monomer for forming a core, also had a low blackness improvement effect as the refractive index of the core was lower than an appropriate range. Through this, it was confirmed that the room temperature impact strength, low temperature impact strength, and blackness were inferior to those of Examples.

Claims (10)

a core containing a repeating unit derived from a diene-based rubber monomer and a repeating unit derived from an aromatic vinyl-based monomer; and a graft shell surrounding the core and containing a repeating unit derived from an alkyl (meth)acrylate monomer and a repeating unit derived from an aromatic (alkyl)methacrylate monomer,
the refractive index of the core is 1.53 to 1.54, and the refractive index of the shell is 1.55 to 1.56; The core has an average particle diameter of 100 to 150 nm, and the core-shell copolymer has an average particle diameter of 110 to 180 nm. According to claim 1,
The aromatic (alkyl) methacrylate monomer is a core-shell copolymer comprising at least one selected from the group consisting of benzyl methacrylate and phenyl methacrylate. According to claim 1,
The core is based on the total content of the core,
A core-shell copolymer comprising 70 to 80% by weight of the repeating unit derived from the diene-based rubber monomer, and 20 to 30% by weight of the repeating unit derived from the aromatic vinyl-based monomer. According to claim 1,
Based on 100 parts by weight of the total of the core-shell copolymer,
The core comprises 50 to 70 parts by weight,
The shell is a core-shell copolymer comprising 1 to 10 parts by weight of the repeating unit derived from the alkyl (meth) acrylate monomer, and 25 to 40 parts by weight of the repeating unit derived from the aromatic (alkyl) methacrylate monomer. According to claim 1,
wherein the core comprises a seed. 6. The method of claim 5,
The seed is included in an amount of 10 to 40% by weight based on the total content of the core-shell copolymer. In the method for producing a core-shell copolymer,
preparing a seed by polymerizing a first core-forming monomer mixture including a diene-based rubber monomer and an aromatic vinyl-based monomer (S10);
preparing a core by polymerizing a second core-forming monomer mixture including a diene-based rubber monomer and an aromatic vinyl-based monomer on the seed (S20); and
Including a step (S30) of preparing a core-shell copolymer by introducing a shell-forming monomer mixture including an alkyl (meth) acrylate monomer and an aromatic (alkyl) methacrylate monomer on the core and performing graft polymerization, and ,
the refractive index of the core is 1.53 to 1.54, and the refractive index of the shell is 1.55 to 1.56; The core has an average particle diameter of 100 to 150 nm, and the core-shell copolymer has an average particle diameter of 110 to 180 nm. The polycarbonate-based resin composition comprising the core-shell copolymer and the polycarbonate-based resin according to any one of claims 1 to 6. 9. The method of claim 8,
The core-shell copolymer is a polycarbonate-based resin composition comprising 1 to 10 parts by weight based on 100 parts by weight of the total polycarbonate-based resin composition. 9. The method of claim 8,
A polycarbonate-based resin composition further comprising an acrylonitrile-butadiene-styrene (ABS) resin.