KR100240981B1 - Resin compositions having improved scratch resistance and impact strength - Google Patents

Abstract

The present invention relates to a resin composition excellent in scratch resistance and impact strength, and more specifically, (A) a polypropylene resin; (B) The main component is ionomer, which is a copolymer of methacrylic acid or acrylic acid and ethylene neutralized with metal ions, and (C) in order to increase compatibility of polypropylene resin with ionomer. Resin having excellent scratch resistance and excellent impact strength and gloss obtained by blending a polypropylene resin grafted with glycidyl methacrylate or a polypropylene resin grafted with maleic anhydride It relates to a composition.

The resin composition of the present invention is easy to disperse organic and inorganic pigments, has excellent gloss, and is suitable for directly coloring resins without coating injection and extrusion molded articles.

Description

Resin compositions having improved scratch resistance and impact strength

The present invention relates to a resin composition excellent in scratch resistance and impact strength, easy to disperse organic and inorganic pigments, excellent in gloss, and which can be used by directly coloring a resin without coating injection and extrusion molded articles.

Polyolefin resins have been widely used in various aspects through extrusion, injection, blow molding, etc. because of their excellent moldability and low price. Polyethylene has excellent impact strength, chemical resistance, and gas permeability, while having high shrinkage and poor scratch resistance. On the other hand, polypropylene has a lower impact strength than polyethylene but is excellent in moldability and scratch resistance, and can be widely modified in physical properties such as flexural modulus and tensile strength. Because of these properties, polypropylene resin is the most widely applied field at present, and studies to further improve the physical properties are ongoing.

Among them, in the case of large injection molding products such as automobile bumpers, since relatively high impact strength and rigidity are required at the same time, techniques related to impact strength reinforcement using rubbers and rigidity reinforcement using inorganic fillers such as talc (Japanese Patent Publication No. 3-7700) , US Pat. No. 5,591,795).

The polyolefin resin compositions having excellent impact strength and rigidity obtained in this way should be made in a color desired by a consumer through a coating process, etc., in order to be a final product. However, the material itself is non-polar, while most of the paint is polar, the adhesion of the coating film is poor, the coating cost is high, and after coating is difficult to remove the coating film of the molded product is difficult to recycle. Therefore, in recent years, there is a trend of increasing interest and research for reducing production costs and facilitating recycling by mixing and coloring a suitable pigment in the material itself without coating.

However, when the coating is not applied, the scratch resistance of the molded article is lower than that of the coated article, and there is a problem that the material may be easily aged as the material is directly exposed to an external environment such as ultraviolet rays. In addition, since there is a limit in dispersibility, it is difficult to express a uniform color of a molded article, and there is a problem in that gloss is inferior to a coated article coated with a clear coating.

Therefore, in the case of the unpainted molded article, material properties excellent in scratch resistance and gloss are required, especially when used as an automotive exterior part, between a body painted with a thermosetting material on a metal and an unpainted part. It is important to reduce the gloss and color difference. To this end, it is necessary to develop a material capable of maintaining high gloss while showing excellent color with excellent dispersibility of the pigment. Since the appearance of the molded product is immediately revealed without a coating film, the moldability must be excellent so that flow marks or weld lines are not exposed. It should be excellent in weather resistance and heat resistance.

In order to improve the scratch resistance of the polyolefin resin composition, U.S. Patent No. 5,585,420 describes a technique of blending silicone oil, a release agent of fatty acid amides, an epoxy resin, and the like into a composition made of a conventional polypropylene / rubber / inorganic filler. It is. However, since the scratch resistance depends only on the role of the surface agent (Slip agent), the effect is limited, there is a problem that high gloss and color appearance is difficult. In addition, in order to improve the scratch resistance of polyolefin resins, U. S. Patent No. 5,484, 824 discloses a technique of blending ethylene-butene copolymer, polyester resin and the like with crystalline polypropylene; U.S. Patent No. 5,420,201 describes a technique in which an epoxy resin is incorporated into a polypropylene resin modified with a carboxylic acid or an unsaturated aromatic monomer.

In addition, U.S. Patent No. 4,968,752 describes a material having excellent scratch resistance and impact strength using an olefinic thermoplastic elastomer crosslinked with an ionomer. In this case, however, the rigidity is low and soft, so it is not suitable for injection molded products, and is mainly used as an interior material sheet, and has a disadvantage of low gloss of molded products. In addition, U. S. Patent No. 4,965, 319 discloses an olefinic thermoplastic elastomer crosslinked with an ethylene ionomer, a material which improves scratch resistance and metal adhesion using ethylene rubber; U.S. Patent 4,871,810 describes a material having improved heat resistance using a polyolefin resin grafted to an ethylene ionomer.

As such, looking at recent research trends, the development of materials using ionomer / polyethylene blends is in progress, since polyethylene has higher compatibility with ionomers than polypropylene. However, blends with polyethylene have excellent impact strengths, but have poor scratch resistance and dimensional stability, and low tensile strength and flexural modulus.

Accordingly, the present inventors have diligently researched to develop a material capable of maintaining high gloss while having excellent scratch resistance, excellent color dispersibility, and excellent color development in a molded article without coating. (A) polypropylene resin; (B) Partially cross-linked form based on ionomer, a copolymer of methacrylic acid or acrylic acid and ethylene partially neutralized with metal ions, compatible with polypropylene in the multicomponent system, and simultaneously reacting with the polar group of ionomer In the case of blending a glycidyl methacrylate or a polypropylene resin grafted with maleic anhydride, which can be used, the interfacial adhesion can be enhanced by enhancing the compatibility between the polypropylene resin and the ionomer. By partially crosslinking with the ionomer, the impact resistance and the scratch resistance can be improved, and the above-described object can be achieved and the present invention has been completed.

Furthermore, by blending an ethylene-octene copolymer having a long side chain octene group in the above-mentioned multicomponent system, the interfacial tension between the polypropylene resin and the ionomer is lowered, thereby reducing the In view of the fact that the dispersibility of the ionomer can be improved, a resin composition having excellent impact strength obtained by blending an ethylene-octene copolymer in the above-described multicomponent system was completed.

Accordingly, an object of the present invention is to provide a resin composition which is excellent in scratch resistance, maintains high gloss with good color dispersibility and moldability, even in a molded article which is not coated, and has excellent impact strength. To provide.

In order to achieve the above object, the resin composition according to the present invention is based on the above findings, and unlike known techniques, ionomers, which are partially neutralized with metal ions or copolymers of acrylic acid and ethylene, It is characteristic to mix | blend with polypropylene resin, and in order to increase compatibility between them, it is characterized by mix | blending the polypropylene resin to which glycidyl methacrylate and maleic anhydride were grafted to these multicomponent systems.

More specifically, the resin composition according to the present invention comprises the following components:

(A) 20 to 80 parts by weight of polypropylene resin;

(B) 10 to 70 parts by weight of an ionomer which is a copolymer of methacrylic acid or acrylic acid neutralized with metal ions and ethylene; And

(C) 5 to 60 parts by weight of polypropylene resin (hereinafter referred to as "GMA-g-PP") to which glycidyl methacrylate (hereinafter referred to as "GMA") is grafted, or maleic anhydride (hereinafter referred to as "MAH"). ) 0.5 to 5 parts by weight of the grafted polypropylene resin (hereinafter referred to as "MAH-g-PP").

In addition, the resin composition according to the present invention may further include 3 to 30 parts by weight of an ethylene-octene copolymer having a long side chain octene group (D) in order to further improve the compatibility between the polypropylene resin and the ionomer. have.

In addition, the resin composition according to the present invention, in order to further improve scratch resistance and glossiness, 0.1 to 5.0 parts by weight of (E) polydimethylsiloxane (PDMS) or 0.1 to 5.0 parts by weight of polymethyl methacrylate (PMMA) It may further include.

Hereinafter, each component which comprises the resin composition of this invention is demonstrated more concretely.

In general, in the polymer blend, in order to increase the impact strength by using a toughening agent, there is a critical size value in which the added impact modifier particles must exist below a certain size among the components of the matrix. The particles must also be uniformly dispersed in the matrix. That is, the impact strength is increased only when the particles of the impact reinforcing material existing as domains are very small and at the same time the domain and the domain spacing are also small.

In the case of the ionomer and the polypropylene resin blend as in the present invention, high gloss resistance, scratch resistance and excellent pigment dispersibility, which are the characteristics of the ionomer, and excellent rigidity and moldability, which are the characteristics of the polypropylene resin, can be simultaneously obtained. Therefore, it can be considered as a non-painted molded article material.

The polypropylene resin constituting the main component in the resin composition of the present invention is an ethylene-propylene block copolymer having 4 to 25% by weight of homopolypropylene or an ethylene monomer having a melt index of 5 to 50 dg / min. In the case of homo polypropylene, tensile strength and flexural modulus are high, but impact strength is low, and ethylene-propylene block copolymer has good impact strength but poor scratch resistance. The appropriate content of the polypropylene resin in the resin composition of the present invention is 20 to 80 parts by weight, preferably 30 to 60 parts by weight. If it is less than 20 parts by weight, the flowability of the composition may worsen, so that the flow marks or weld lines may be severe in the appearance of the molding, and when it exceeds 80 parts by weight, the impact strength may be lowered.

In the composition of the present invention, the ionomer for blending with a polypropylene resin to impart scratch resistance, pigment dispersibility and high gloss to the composition is a form in which polyethylene is copolymerized with methacrylic acid or acrylic acid. 3 to 10% by weight, 20 to 80% of the total acid is neutralized with lithium ions (Li ⁺ ), sodium ions (Na ⁺ ), zinc ions (Zn ²⁺ ). The higher the acid content and the degree of neutralization, the higher the surface hardness and tensile strength, while the impact strength is lowered. Preferably, the melt index is 0.5 to 10 dg / min. The appropriate content of ionomer in the resin composition of the present invention is 10 to 70 parts by weight, preferably 15 to 60 parts by weight. If it is less than 10 parts by weight, the scratch resistance is lowered. If it is more than 70 parts by weight, the flowability is lowered and the rigidity of the material is lowered.

However, ionomers blended with polypropylene resins are comparable to pure rubbers such as ethylene-propylene polymers (hereinafter referred to as "EPR") and ethylene-propylene-diene terpolymers (hereinafter referred to as "EPDM"). Hard; Polypropylene also has a relatively poor impact strength; In the case of polypropylene and ionomer blends, the interfacial adhesion is low due to incompatibility, and the impact strength of the composition is low because large ionomer particles are present in the polypropylene matrix. In particular, in order to be used in products requiring high impact strength even at low temperatures such as automobile bumpers, it is most important to increase the impact strength.

In order to increase the compatibility of the polypropylene-based resin with the ionomer, the resin composition of the present invention is grafted with GMA, which is compatible with the polypropylene and simultaneously reacts with the polar group of the ionomer to form a partial crosslink. It is characterized by mix | blending polypropylene resin or polypropylene resin in which MAH was grafted.

GMA-grafted polypropylene resin is a twin screw extruder (cylinder temperature: 180) by blending a polypropylene resin with 0.1 to 5.0 parts by weight of peroxide, 0.1 to 10 parts by weight of styrene monomer, and 0.1 to 10 parts by weight of glycidyl methacrylate. ˜250 ° C.), the GMA graft rate is 0.1 to 5.0% by weight, and the melt index is 5 to 50 dg / min. GMA-g-PP is compatible with polypropylene and at the same time can be partially crosslinked by reacting with the polar group of the ionomer to increase the interfacial adhesion between the ionomer and the polypropylene resin, and to improve impact resistance and stretch resistance. . The content of GMA-g-PP blended in the resin composition is 5 to 60 parts by weight, preferably 10 to 50 parts by weight. If less than 5 parts by weight, the morphology of the composition is worse and the impact strength is lowered. If it exceeds 60 parts by weight, the tensile strength and flexural modulus of the composition is lowered and the moldability is also lowered.

In addition, the polypropylene resin grafted with MAH is 0.5 to 6.0% by weight of maleic anhydride grafted to polypropylene, characterized by a very high melt index. Suitable content of the composition is 0.5 to 5.0 parts by weight based on MAH-g-PP having a MAH graft rate of 6.0% by weight, and less than 0.5 parts by weight, the scratch resistance and tensile strength are insignificant, and the amount is greater than 5.0 parts by weight. In this case, the impact strength deteriorates.

In addition, the ethylene-octene copolymer (hereinafter referred to as ″ EOR ″) blended in the resin composition according to the present invention has higher surface hardness and glossiness and superior impact strength than EPR and EPDM, which are conventionally formulated as impact modifiers. have. In particular, the long side chain octene group lowers the interfacial tension between the polypropylene resin and the ionomer to reduce the size of the domain, thereby further improving the impact strength. Preferably, the octene content is 5 to 30% by weight, and the melt index is preferably 0.5 to 20 dg / min. The content of EOR blended into the resin composition is 3 to 30 parts by weight, preferably 5 to 25 parts by weight. If it is less than 3 parts by weight, the effect of improving the compatibility of the polypropylene resin and the ionomer is insignificant. If it exceeds 30 parts by weight, the impact strength is improved, but scratch resistance and color development are lowered.

In addition, the scratch resistance of the composition can be further improved by blending 0.1 to 5.0 parts by weight of polydimethylsiloxane (PDMS) as the silicone oil discharged to the surface of the molded article and acting as a slip agent to the resin composition of the present invention. . Preferably the viscosity is 5,000 ~ 100,000 cst. Moreover, the scratch resistance and glossiness of a product can be supplemented by further mix | blending 0.1-5.0 weight part of polymethylmethacrylates (PMMA) with the resin composition of this invention.

In the resin composition according to the present invention, the compatibility between the polypropylene and the ionomer is enhanced by blending GMA-g-PP, MAH-g-PP, or EOR having an octene group having a long side chain in the composition. By improving the dispersibility of the ionomer in the resin matrix, the excellent scratch resistance, pigment dispersibility and high gloss of the ionomer can be exhibited to the maximum, which makes it applicable to non-painted injection or extrudates. It is possible to express the color required by the final product by directly coloring with a pigment.

In addition, the ionomer maintains a crosslinked state in the form of ionic bonds in a polypropylene resin matrix at room temperature, thereby improving high impact strength and scratch resistance, and is excellent because the bond is broken at a high temperature (170 ° C) or higher at a molding temperature. It shows moldability. Therefore, even when the composition of the present invention is applied to a large injection-molded product such as an automobile bumper, no weld line or flow marks appear on the surface of the non-paintable molded article.

EMBODIMENT OF THE INVENTION Hereinafter, the structure and effect | action of the resin composition of this invention are given more concretely, for an Example and a comparative example. However, the present invention is not limited to these examples.

<Example 1>

(A) a melt index of 25dg / min, and an isotactic index of 98% or more of polypropylene resin ⁽¹⁾ 80 parts by weight; (B) 10% by weight of ionomer ⁽¹⁾ in which methacrylic acid was copolymerized with 7% and about 60% of the acid content was neutralized with sodium ions (Na ⁺ ); (C) 10 parts by weight of GMA-g-PP ⁽¹ ) with a melt index of 13 dg / min and 0.5% by weight of GMA, and ¹ weight of MAH-g-PP ⁽¹⁾ with 3% by weight of MAH. The mixture consisting of parts was granulated at a cylinder temperature of 180 to 210 ° C. through a twin screw extruder to obtain a composition obtained. Its physical properties are shown in Table 1.

The measured physical properties shown in Table 1 were prepared by injection molding according to ASTM standards, and the melt index was measured under a load of 230 ° C. and 2.16 kg according to ASTM D-1238, and the flexural modulus was ASTM D-790, impact. The strength was measured according to the standard of ASTM D-256, and the scratch resistance and glossiness were evaluated relative.

<Examples 2-5>

10 parts by weight of GMA-g-PP ⁽¹⁾ and ¹ part by weight of MAH-g-PP ⁽¹⁾ of Example 1 were fixed, and the contents of the polypropylene resin ⁽¹⁾ and the ionomer ⁽¹⁾ were shown in Table 1. It was changed as described in the same manner as in Example 1 to obtain a composition, the results of measuring the physical properties are shown in Table 1.

<Examples 6 to 8>

60 parts by weight of polypropylene resin ^(1), 10 parts by weight of GMA-g-PP ⁽¹⁾ and ¹ part by weight of MAH-g-PP ⁽¹⁾ have a melt index of 1 dg / min and an octene content of 25% by weight. The contents of EOR ⁽¹⁾ and ionomer ⁽¹⁾ were changed as shown in Table 1 to carry out the same method as in Example 1 to obtain a composition, the physical properties thereof are shown in Table 1.

ingredient Example One 2 3 4 5 6 7 8 Polypropylene ⁽¹⁾ 80 65 50 35 20 60 60 60 Ionomer ⁽¹⁾ 10 25 40 55 70 25 20 10 EOR ⁽¹⁾ - - - - - 5 10 20 GMA-g-PP ⁽¹⁾ 10 10 10 10 10 10 10 10 MAH-g-PP ⁽¹⁾ One One One One One One One One Test Items ASTM unit Melt index D-1238 dg / min 18 15 13 10 7 14 12 12 Flexural modulus D-790 ㎏ / ㎠ 16000 13000 10000 8000 6500 12500 10500 9500 Impact strength 23 ℃ D-256 Kgcm / cm 15 35 NB NB NB NB NB NB -30 ℃ D-256 4 10 15 30 NB 12 13 12 Glossiness ^* △ ○ ◎ ◎ ◎ ○ ○ ○ Scratch Resistance ^** △ ○ ○ ○ ○ ○ ○ △ * Glossiness: ◎ ... Very good, ○ ... Good, △ ... Normal, × ... Poor ** Scratch resistance: ◎ ... Very good, ○ ... Good, △. .. Normal, × ... Poor

<Example 9>

(A) a melt index of 30dg / min, and the ethylene monomer is 6% of the copolymer polypropylene resin ⁽²⁾ 70 parts by weight; (B) 20 parts by weight of ionomer ⁽²⁾ , in which methacrylic acid was copolymerized 4% and about 70% of the acid content was neutralized with zinc ions (Zn ²⁺ ); (C) a melt index of 20dg / min is, 1.0% GMA grafted ^{GMA-g-PP (2)} 5 parts by weight; (D) A mixture consisting of 5 parts by weight of an EOR ⁽²⁾ having a melt index of 2 dg / min and an octene content of 12.5% by weight was obtained in the same manner as in Example 1 to obtain a composition. Shown in

<Examples 10-13>

20 parts by weight of the ionomer ⁽²⁾ and 5 parts by weight of the EOR ⁽²⁾ of Example 2 were fixed, and the contents of the polypropylene resin ⁽²⁾ and the GMA-g-PP ⁽²⁾ were changed as shown in Table 2. The composition was obtained in the same manner as in Example 1, and the results of measuring the physical properties thereof are shown in Table 2.

<Examples 14-17>

To a mixture of the same composition as in Example 12 ^, the content of MAH-g-PP ⁽²⁾ grafted with 6% by weight of MAH was changed as shown in Table 2 to obtain the composition by the same method as in Example 1, Its physical properties are shown in Table 2.

ingredient Example 9 10 11 12 13 14 15 16 17 Polypropylene ⁽²⁾ 70 60 50 35 20 50 50 50 50 Ionomer ⁽²⁾ 20 20 20 20 20 20 20 20 20 EOR ⁽²⁾ 5 5 5 5 5 5 5 5 5 GMA-g-PP ⁽²⁾ 5 15 25 40 55 25 25 25 25 MAH-g-PP ⁽²⁾ - - - - - One 2 3 4 Test Items ASTM unit Melt index D-1238 dg / min 20 12 10 10 10 9 9 8 8 Flexural modulus D-790 ㎏ / ㎠ 13500 12000 11500 10500 9000 12000 12300 12500 13000 Impact strength 23 ℃ D-256 Kgcm / cm 17 NB NB NB NB NB NB 36 33 -30 ℃ D-256 5 9 11 12 14 10 9 8 8 Glossiness ^* ○ ○ ○ ○ △ ○ ○ ○ ○ Scratch Resistance ^** △ ○ ○ ○ △ ○ ○ ◎ ◎ * Glossiness: ◎ ... Very good, ○ ... Good, △ ... Normal, × ... Poor ** Scratch resistance: ◎ ... Very good, ○ ... Good, △. .. Normal, × ... Poor

<Example 18>

(A) a melt index of 20dg / min, and an isotactic index of 98% or more polypropylene resin ³ 55 parts by weight; (B) 20% by weight of ionomer ⁽³⁾ in which methacrylic acid was copolymerized with 7% and about 60% of the acid content was neutralized with zinc ions (Zn ²⁺ ); (C) a melt index of 15dg / min and, GMA is 2.0% by weight of grafted ^{GMA-g-PP (3)} 20 parts by weight, MAH is 1 wt% grafted ^{MAH-g-PP (3)} 2 wt. part; (D) 5 parts by weight of EOR ⁽³⁾ having a melt index of 5 dg / min and an octene content of 20% by weight; (E) A mixture consisting of 0.5 parts by weight of polydimethylsiloxane having a viscosity of 12,500 cst was obtained in the same manner as in Example 1 to obtain a composition, and the results of measuring the physical properties thereof are shown in Table 3.

<Examples 19 to 21>

In Example 18, except that the content of the polydimethylsiloxane was changed as shown in Table 3, the composition was obtained in the same manner as in Example 1 except for changing the content of the polydimethylsiloxane, and the physical properties thereof are shown in Table 3.

<Examples 22-25>

In Example 18, instead of polydimethylsiloxane, polymethylmethacrylate was used and the composition was carried out in the same manner as in Example 1 with the same composition except that the content thereof was changed as shown in Table 3. It obtained, and the physical property is shown in Table 3.

<Example 26>

To the mixture of the same composition as in Example 19, 1.0 part by weight of polymethyl methacrylate was mixed and carried out in the same manner as in Example 1 to obtain a composition, and the physical properties thereof are shown in Table 3.

ingredient Example 18 19 20 21 22 23 24 25 26 Polypropylene ⁽³⁾ 55 55 55 55 55 55 55 55 55 Ionomer ⁽³⁾ 20 20 20 20 20 20 20 20 20 EOR ⁽³⁾ 5 5 5 5 5 5 5 5 5 GMA-g-PP ⁽³⁾ 20 20 20 20 20 20 20 20 20 MAH-g-PP ⁽³⁾ 2 2 2 2 2 2 2 2 2 Polydimethylsiloxane 0.5 1.0 2.0 3.0 - - - - 1.0 Polymethyl methacrylate - - - - 0.5 1.0 2.0 3.0 1.0 Test Items ASTM unit Melt index D-1238 dg / min 12 10 10 10 10 9 9 8 8 Flexural modulus D-790 ㎏ / ㎠ 11000 10900 10800 10600 11000 11100 11200 11200 11100 Impact strength 23 ℃ D-256 Kgcm / cm NB NB NB NB NB NB NB NB NB -30 ℃ D-256 9 10 11 11 9 8 8 8 9 Glossiness ^* ○ ○ ○ ○ ○ ◎ ◎ ◎ ◎ Scratch Resistance ^** ○ ◎ ◎ ◎ ○ ○ ○ ◎ ◎ * Glossiness: ◎ ... Very good, ○ ... Good, △ ... Normal, × ... Poor ** Scratch resistance: ◎ ... Very good, ○ ... Good, △. .. Normal, × ... Poor

<Comparative Examples 1-4>

Polyethylene resin with 25 dg / min melt, ionomer ⁽¹⁾ , ethylene-propylene rubber with a pattern viscosity of 40ML _{1 + 4} (100 ° C), barium sulfate, polyethylene with 1% by weight of MAH grafted (MAH-g-PE ), And the mixture consisting of polydimethylsiloxane having a viscosity of 12,500 cst was changed to the content shown in Table 4, and was carried out in the same manner as in Example 1 to obtain a composition, and the results of measuring the physical properties thereof are shown in Table 4.

<Comparative Example 5-8>

The mixture consisting of polypropylene resin ⁽²⁾ , ethylene-propylene rubber, barium sulfate, and polydimethylsiloxane was changed to the content shown in Table 4, and was carried out in the same manner as in Example 1 to obtain a composition, and the results of measuring the physical properties thereof were obtained. Table 4 shows.

ingredient Comparative Example One 2 3 4 5 6 7 8 Polyethylene 80 70 70 60 - - - - Polypropylene ⁽¹⁾ - - - - 70 70 70 70 Ionomer ⁽¹⁾ 20 30 20 20 - - - - Ethylene-propylene rubber - - 10 10 30 25 20 20 Barium Sulfate (BaSO ₄ ) - - - 10 - 5 10 10 MAH-g-PE - 2 2 2 - - - - Polydimethylsiloxane - - 2 2 - - 2 4 Test Items ASTM unit Melt index D-1238 dg / min 19 15 13 11 15 16 16 17 Flexural modulus D-790 ㎏ / ㎠ 6600 6400 6000 7500 9500 10000 11000 10600 Impact strength 23 ℃ D-256 Kgcm / cm 15 35 38 30 NB NB 30 34 -30 ℃ D-256 6 10 11 9 12 10 9 10 Glossiness ^* ○ ○ ○ ○ △ △ ○ ○ Scratch Resistance ^** × △ △ △ × × × △ * Glossiness: ◎ ... Very good, ○ ... Good, △ ... Normal, × ... Poor ** Scratch resistance: ◎ ... Very good, ○ ... Good, △. .. Normal, × ... Poor

The resin composition according to the present invention can exhibit maximum scratch resistance, pigment dispersibility and high gloss, and can be applied to non-coated injection or extrudates, and the final product can be directly colored by using a pigment. This color can be expressed. In addition, the resin composition of the present invention has excellent moldability, and even when applied to a large-scale injection molded product such as an automobile bumper, no weld lines, traces, or the like appear on the surface of the non-paintable molded article.

Claims (7)

(A) 20 to 80 parts by weight of a polypropylene resin selected from homopolypropylene having a melt index of 5 to 50 dg / min or an ethylene-propylene block copolymer having 4 to 25% by weight of an ethylene monomer; (B) Polyethylene methacrylic acid or acrylic acid is copolymerized, the acid content is 3 to 10% by weight, 20 to 80% of the total acid is lithium ions (Li ⁺ ), sodium ions (Na ⁺ ) or zinc 10 to 70 parts by weight of an ionomer neutralized with ions (Zn ²⁺ ); And (C) Glycidyl methacrylate (GMA) has a graft ratio of 0.1 to 5.0% by weight, molten paper 5 to 60 parts by weight of polypropylene resin having a number of 5 to 50 dg / min, or 0.5 to 5 parts by weight of polypropylene resin having a graft ratio of maleic anhydride of 0.5 to 6.0% by weight Resin composition characterized by the above-mentioned. (D) The resin composition according to claim 1, further comprising 3 to 30 parts by weight of an ethylene-octene copolymer having an octene group of a long side chain. The resin composition according to claim 2, wherein the (D) ethylene-octene copolymer has an octene content of 5 to 30% by weight and a melt index of 0.5 to 20 dg / min. The resin according to any one of claims 1 to 3, further comprising 0.1 to 5.0 parts by weight of (E) polydimethylsiloxane (PDMS) or 0.1 to 5.0 parts by weight of polymethyl methacrylate (PMMA). Composition. The resin composition according to claim 4, wherein (E) polydimethylsiloxane (PDMS) has a viscosity of 5,000 to 100,000 cst. The resin composition according to claim 1, wherein the ionomer (B) has a melt index of 0.5 to 10 dg / min. The polypropylene resin grafted with (C) glycidyl methacrylate (GMA) is 0.1 to 5.0 parts by weight of peroxide, 0.1 to 10 parts by weight of styrene monomer, and glycidyl meta according to claim 1. A resin composition, characterized in that obtained by blending 0.1 to 10 parts by weight of acrylate and glycidyl methacrylate to polypropylene using an extruder.