阅读说明：本技术 热塑性树脂组合物 (Thermoplastic resin composition ) 是由 金成均 金瑞和 崔银庭 姜秉逸 申东建 金荣民 于 2020-10-06 设计创作，主要内容包括：本发明提供一种热塑性树脂组合物,包含：具有二烯类橡胶接枝共聚物和乙烯基氰-芳香族乙烯基类共聚物的基体树脂；具有结晶单元的烯烃类共聚物；和金属颜料。(The present invention provides a thermoplastic resin composition comprising: a base resin having a diene rubber graft copolymer and a vinyl cyanide-aromatic vinyl copolymer; an olefin copolymer having a crystalline unit; and a metallic pigment.)

1. A thermoplastic resin composition comprising:

a base resin comprising a diene-based rubber graft copolymer and a vinyl cyanide-aromatic vinyl-based copolymer;

an olefin copolymer having a crystalline unit; and

a metallic pigment.

2. The thermoplastic resin composition of claim 1, wherein said matrix resin further comprises an acrylic rubber graft copolymer.

3. The thermoplastic resin composition according to claim 1, wherein the diene-based rubber graft copolymer has a rubber particle size of 0.05 μm to 0.5 μm.

4. The thermoplastic resin composition of claim 1, wherein the diene-based rubber graft copolymer is contained in an amount of 10 to 40 parts by weight, relative to 100 parts by weight of the base resin.

5. The thermoplastic resin composition according to claim 1, wherein the vinyl cyanide-aromatic vinyl-based copolymer is contained in an amount of 60 to 80 parts by weight, relative to 100 parts by weight of the base resin.

6. The thermoplastic resin composition of claim 2, wherein said acrylic rubber graft copolymer has a rubber particle size of 0.05 to 0.6 μm.

7. The thermoplastic resin composition of claim 2, wherein the acrylic rubber graft copolymer is contained in an amount of 5 to 20 parts by weight, relative to 100 parts by weight of the base resin.

8. The thermoplastic resin composition according to claim 1, wherein said crystalline unit is at least one selected from the group consisting of an ethylene unit and a propylene unit.

9. The thermoplastic resin composition according to claim 1, wherein the olefin-based copolymer comprises at least one functional group selected from an acetate group and an acrylate group.

10. The thermoplastic resin composition according to claim 1, wherein the olefin-based copolymer is contained in an amount of 1 to 10 parts by weight, relative to 100 parts by weight of the base resin.

11. The thermoplastic resin composition of claim 1, wherein said metallic pigment comprises metallic flakes and a polymeric carrier.

12. The thermoplastic resin composition of claim 11, wherein said polymer carrier is at least one selected from the group consisting of a polyethylene carrier, a polymethylmethacrylate carrier, and a styrene-acrylonitrile copolymer carrier.

13. The thermoplastic resin composition of claim 1, wherein the metallic pigment is contained in an amount of 0.1 to 12 parts by weight, relative to 100 parts by weight of the base resin.

Technical Field

[ Cross-reference to related applications ]

This application claims the benefit of korean patent application No. 10-2019-.

[ technical field ]

The present invention relates to a thermoplastic resin composition, and in particular, to a thermoplastic resin composition from which a resin having excellent flowability and an injection molded product having excellent brightness, appearance quality and chemical resistance can be provided.

Background

Recently, research into metal resins for allowing plastics to exhibit a metallic color by adding a metal pigment to diene-based graft copolymers has been expanding.

However, when a metal pigment is added to the diene-based graft copolymer, there is a problem that the fluidity of the resin is significantly reduced. Further, there are problems as follows: in portions where the thickness of the molded article prepared using the metal resin is changed, or at the ends of the molded article due to a great difference in flow rate between the metal pigment and the polymer fluid, defects in appearance quality occur.

Meanwhile, conventional studies to solve the above problems have not been directed to improving physical properties of a resin itself, but have been directed to improving only properties of a molded article itself by controlling conditions when the molded article is manufactured by molding the resin.

Therefore, there is a need for a thermoplastic resin composition from which molded articles having excellent physical properties such as appearance quality and chemical resistance can be provided without decreasing the flowability of the resin even if a metal pigment is added to the diene-based graft copolymer.

[ Prior art documents ]

[ patent document ]

(patent document 1) CN109836683A

Disclosure of Invention

Technical problem

An aspect of the present invention provides a thermoplastic resin composition from which a resin having excellent flowability can be provided and an injection molded product having excellent brightness, appearance quality, and chemical resistance can be provided.

However, the problems to be solved by the present invention are not limited to the above-mentioned problems, and other problems not mentioned will be clearly understood by those skilled in the art from the following description.

Technical scheme

In order to solve the above problems, one embodiment of the present invention provides a thermoplastic resin composition comprising: a base resin having a diene rubber graft copolymer and a vinyl cyanide-aromatic vinyl copolymer; an olefin copolymer having a crystalline unit; and a metallic pigment.

Advantageous effects

The thermoplastic resin composition according to the present invention can provide a resin having excellent flowability, and can provide an injection molded product having excellent brightness, appearance quality, and chemical resistance.

Detailed Description

Hereinafter, the present invention will be described in more detail in order to more clearly understand 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 the words or terms should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and the technical spirit of the present invention, based on the principle that the inventor can appropriately define the meaning of the words or terms to best explain the present invention.

In the present specification, when a portion "comprises" a component, unless otherwise specified, this means that other components may be further included without excluding other components.

One embodiment of the present invention provides a thermoplastic resin composition comprising: a base resin having a diene rubber graft copolymer and a vinyl cyanide-aromatic vinyl copolymer; an olefin copolymer having a crystalline unit; and a metallic pigment.

According to an embodiment of the present invention, the base resin may further include an acrylic rubber graft copolymer.

Hereinafter, the components of the thermoplastic resin composition according to one embodiment of the present invention will be described in detail.

1. Matrix resin

1) Diene rubber graft copolymer

The diene-based rubber graft copolymer can provide excellent heat resistance, impact resistance and processability to the thermoplastic resin composition.

The diene rubber graft copolymer may be obtained by graft-copolymerizing a vinyl monomer onto a diene rubber polymer, preferably an aromatic vinyl monomer and a vinyl cyanide monomer onto a diene rubber polymer.

The diene-based rubber polymer may be a polymerization product of a diene-based monomer, which may be at least one selected from the group consisting of 1, 3-butadiene, isoprene, chloroprene and piperylene, and specifically, the diene-based monomer may be 1, 3-butadiene.

The aromatic vinyl monomer may be at least one selected from the group consisting of styrene, α -methylstyrene, α -ethylstyrene, and p-methylstyrene, and particularly, the aromatic vinyl monomer may be styrene.

The vinyl cyanide-based monomer may be at least one selected from acrylonitrile, methacrylonitrile, phenylacetonitrile, and α -chloroacrylonitrile, and particularly, the vinyl cyanide-based monomer may be acrylonitrile.

According to one embodiment of the present invention, the diene-based rubber graft copolymer may have a rubber particle size of 0.05 μm to 0.5 μm. When the rubber particle size of the diene-based rubber graft copolymer is within the above range, the heat resistance, impact resistance and processability of the thermoplastic resin composition can be improved.

According to an embodiment of the present invention, the diene-based rubber graft copolymer may be contained in an amount of 10 parts by weight to 40 parts by weight with respect to 100 parts by weight of the base resin. Specifically, the amount of the diene-based rubber graft copolymer may be 10 to 30 parts by weight, 10 to 20 parts by weight, 10 to 15 parts by weight, or 15 to 20 parts by weight with respect to 100 parts by weight of the base resin. When the amount of the diene-based rubber graft copolymer is within the above range, the heat resistance, impact resistance and processability of the thermoplastic resin composition can be improved.

2) Vinyl cyanide-aromatic vinyl copolymer

The vinyl cyanide-aromatic vinyl-based copolymer can provide excellent transparency, gloss, impact resistance, chemical resistance and heat resistance to the thermoplastic resin composition.

The vinyl cyanide-aromatic vinyl copolymer may be obtained by copolymerization of an aromatic vinyl compound and a vinyl cyanide compound, and is preferably obtained by copolymerization of an aromatic vinyl monomer and a vinyl cyanide monomer. The aromatic vinyl-based monomer and the vinyl cyanide-based monomer may be the same monomers as described in 1.1).

According to an embodiment of the present invention, the content of the vinyl cyanide-aromatic vinyl-based copolymer may be 60 parts by weight to 80 parts by weight with respect to 100 parts by weight of the base resin. Specifically, the amount of the vinyl cyanide-aromatic vinyl-based copolymer may be 70 to 80 parts by weight, 75 to 80 parts by weight, 77 to 80 parts by weight, 75 to 77 parts by weight, or 70 to 77 parts by weight, relative to 100 parts by weight of the base resin. When the amount of the vinyl cyanide-aromatic vinyl-based copolymer is within the above range, the transparency, gloss, impact resistance, chemical resistance and heat resistance of the thermoplastic resin composition may be improved.

3) Acrylic rubber graft copolymer

The acrylic rubber graft copolymer can provide excellent weather resistance, impact resistance, elongation, coloring property, chemical resistance, processability, surface gloss property and whitening property to the thermoplastic resin composition.

The acrylic rubber graft copolymer may be obtained by graft-copolymerizing a vinyl monomer onto an acrylic rubber polymer, and preferably, by graft-copolymerizing an aromatic vinyl monomer and a vinyl cyanide monomer onto an acrylic rubber polymer. The acrylic rubber polymer may be prepared by crosslinking a (meth) acrylate monomer, preferably a C4-C10 alkyl (meth) acrylate monomer, more preferably butyl acrylate. The aromatic vinyl-based monomer and the vinyl cyanide-based monomer may be the same monomers as described in 1.1).

According to an embodiment of the present invention, the rubber particle size of the acrylic rubber graft copolymer may be 0.05 μm to 0.6 μm. When the rubber particle size of the acrylic rubber graft copolymer is within the above range, the weather resistance, impact resistance, elongation, colorability, chemical resistance, processability, surface gloss property and whitening property of the thermoplastic resin composition can be further improved.

According to an embodiment of the present invention, the acrylic rubber graft copolymer may be contained in an amount of 5 parts by weight to 20 parts by weight with respect to 100 parts by weight of the base resin. Specifically, the amount of the acrylic rubber graft copolymer may be 5 to 15 parts by weight, 5 to 10 parts by weight, 5 to 8 parts by weight, or 8 to 10 parts by weight, relative to 100 parts by weight of the base resin. When the amount of the acrylic rubber graft copolymer is within the above range, the elongation, weather resistance, chemical resistance, coloring property, processability, surface gloss property and whitening property of the thermoplastic resin composition can be remarkably improved.

2. Olefin copolymer having crystalline unit

The olefin-based copolymer having a crystalline unit has excellent flowability and can improve processability and chemical resistance of the thermoplastic resin composition. In particular, the olefin-based copolymer having a crystalline unit may allow the thermoplastic resin composition to form a resin having excellent flowability, and the thermoplastic resin composition may form a molded article having excellent brightness, appearance quality, and chemical resistance.

Further, the olefin-based copolymer having a crystalline unit is contained in the thermoplastic resin composition together with a metallic pigment, thereby improving appearance characteristics of resins and molded articles obtained from the composition. In particular, the olefin-based copolymer having a crystalline unit has excellent compatibility with a polymer carrier that will be included in the metallic pigment described below, and can maximize the arrangement and dispersion of the metallic pigment in the thermoplastic resin, so that a molded article obtained from the thermoplastic resin composition can have excellent appearance quality.

According to an embodiment of the present invention, the crystallization unit may be at least one unit selected from the group consisting of an ethylene unit and a propylene unit, and preferably may be an ethylene unit.

According to an embodiment of the present invention, the olefin-based copolymer may include at least one functional group selected from an acetate group and an acrylate group, and preferably includes an acetate group. In this case, the olefin-based copolymer having a crystalline unit may have excellent compatibility with the matrix resin, and thus, the thermoplastic resin composition may form a resin having excellent flowability.

The olefin-based copolymer having a crystalline unit may be at least one copolymer selected from the group consisting of an ethylene-vinyl acetate copolymer, an ethylene-ethyl acrylate copolymer, and an ethylene-butyl acrylate copolymer, and is preferably an ethylene-vinyl acetate copolymer. In this case, the flowability of the resin prepared from the thermoplastic resin composition can be improved, and the thermoplastic resin composition can improve the brightness, appearance quality, and chemical resistance of a molded article prepared from the composition.

According to an embodiment of the present invention, the content of the olefin-based copolymer may be 1 to 10 parts by weight with respect to 100 parts by weight of the base resin. Specifically, the amount of the olefin-based copolymer may be 1 to 5 parts by weight, or 5 to 10 parts by weight, relative to 100 parts by weight of the base resin. When the amount of the olefin-based copolymer is within the above range, the compatibility of the olefin-based copolymer with the matrix resin is excellent, thereby improving the appearance quality and chemical resistance of a molded article prepared from the thermoplastic resin composition.

3. Metallic pigments

The metallic pigment may allow the thermoplastic resin composition to form a molded article having excellent brightness, appearance quality, and chemical resistance.

According to one embodiment of the present invention, the metallic pigment may comprise metallic flakes and a polymeric carrier. When the metallic pigment comprises a polymer carrier, the polymer carrier has excellent compatibility with the olefin-based copolymer having a crystalline unit, whereby the arrangement and dispersion of the metallic pigment can be maximized.

The metal foil may be at least one selected from the group consisting of aluminum foil, zinc foil, copper foil, nickel foil, and stainless steel foil. The metal flake may preferably be an aluminum flake, and in this case, the thermoplastic resin composition may improve the brightness and appearance quality of a molded article prepared from the composition.

According to an embodiment of the present invention, the polymer carrier may be at least one selected from the group consisting of a polyethylene carrier, a polymethylmethacrylate carrier, and a styrene-acrylonitrile copolymer carrier. The polymeric carrier may preferably be a polyethylene carrier, most preferably a polyethylene wax carrier. In this case, the thermoplastic resin composition can improve the brightness, appearance quality and chemical resistance of molded articles prepared from the composition.

According to an embodiment of the present invention, the content of the metallic pigment may be 0.05 parts by weight to 12 parts by weight with respect to 100 parts by weight of the base resin. Specifically, the amount of the metallic pigment may be 0.1 to 10 parts by weight, 1 to 5 parts by weight, or 5 to 10 parts by weight, relative to 100 parts by weight of the base resin. When the amount of the metallic pigment is within the above range, the fluidity of the resin prepared from the thermoplastic resin composition can be improved, and the thermoplastic resin composition can improve the appearance quality of a molded article prepared from the composition. For example, flow marks or weld lines can be prevented from occurring in the molded article, and a metal-like appearance color can be obtained as desired.

Hereinafter, for the purpose of describing the present invention in detail, details will be given with reference to examples. However, the embodiments according to the present invention may be modified in various other forms, and the scope of the present invention is not to be construed as being limited to the embodiments described below. The embodiments of the present description are provided to more fully explain the present invention to those of ordinary skill in the art.

Examples and comparative examples

The specifications of the components used in the following examples and comparative examples are as follows.

(A) Diene-based rubber graft copolymer: an acrylonitrile-butadiene-styrene graft copolymer (DP270E, LG Chem Co.) having a rubber particle size of 0.05 μm to 0.5 μm was used.

(B) Vinyl cyanide-aromatic vinyl copolymer: a styrene-acrylonitrile copolymer (80HF, LG Chem Co.) containing 24 wt% acrylonitrile was used.

(C) Acrylic rubber graft copolymer: acrylonitrile-styrene-acrylate graft copolymer (SA927, LG Chem Co.) having a rubber particle size of 0.05 to 0.6 μm was used.

(D) Olefin-based copolymer having crystalline unit: an ethylene-vinyl acetate copolymer (EEA-28025, LG Chem Co.) was used.

(E) Metallic pigment:

(E-1) use is made of a metallic pigment (220-20-E, Silverline Co.) comprising a polyethylene wax carrier.

(E-2) use was made of a metallic pigment (838-20-P, Silverline Co.) comprising a polymethyl methacrylate carrier.

Thermoplastic resin compositions were prepared by mixing the above components in the amounts shown in the following tables 1 to 3.

Test example 1

The thermoplastic resin compositions of examples and comparative examples were put into an extruder (barrel temperature: 230 ℃ C.), followed by melting, mixing and extruding to manufacture pellets, and physical properties thereof were evaluated by the following methods, and the results are shown in tables 1 to 3.

1) Melt Index (MI) measurement

After melting for 10 minutes under the conditions of a temperature of 220 ℃ and a load of 10kg, the weight of the resin was measured using MI-4 manufactured by GOTTFERT co.

Test example 2

The pellets prepared in test example 1 were injection molded to prepare test specimens, and physical properties thereof were evaluated by the following methods, and the results are shown in tables 1 to 3 below.

1) Color L value measurement

The color L value of the sample was measured using a colorimeter (Ci7860, x-rite Co.).

2) Evaluation of appearance quality

Since injection molding is performed using a mold having two gates during injection molding, flow marks may occur. The appearance of the sample was observed with the naked eye, and the quality of the appearance was evaluated according to the following evaluation criteria.

O: with no or little flow marks

And (delta): the flow marks are visible

X: the region where flow marks occur is clearly visible

3) Evaluation of chemical resistance

According to ASTM D1693, the test specimen was fixed to a 1.5% strain jig at room temperature, followed by coating the test specimen with an isopropyl alcohol solution (concentration: 70%), and after 10 minutes, the chemical resistance was evaluated according to the following evaluation criteria by observing the change of the test specimen with the naked eye.

O: no change in the sample

X: cracks or complete breaking of the specimen were observed

[ Table 1]

[ Table 2]

[ Table 3]

Referring to tables 1 to 3, it can be confirmed from the melt index and the color L value that the thermoplastic resin compositions of examples 1 to 15 including both the olefin-based copolymer having a crystalline unit and the metallic pigment can provide resins having the same or more excellent level of flowability as compared to the thermoplastic resin compositions of comparative examples 1 to 4, and also provide injection-molded products having the same or more excellent level of brightness. Specifically, it was confirmed that example 2 is superior to comparative example 1, example 3 is superior to comparative example 3, and example 7 is superior to comparative example 2 in terms of fluidity and brightness.

Further, it can be confirmed that the thermoplastic resin compositions of examples 1 to 15 can provide injection molded products having more excellent appearance quality and chemical resistance than the thermoplastic resin compositions of comparative examples 1 to 4 which do not contain the olefin-based copolymer having a crystalline unit.

Further, it was confirmed from examples 1 to 15 that both the color L value and the appearance quality can be improved when the metallic pigment is contained in an appropriate range.

Therefore, it can be seen that the thermoplastic resin composition according to one embodiment of the present invention can provide a resin having excellent flowability, and also provide a molded article having excellent brightness, appearance quality, and chemical resistance.