KR100638183B1 - The polyolefin composition with improved metal-gloss and a product manufactured using the same - Google Patents

Abstract

The present invention relates to a polyolefin resin composition having excellent metallic luster and a molded article manufactured using the same, and more particularly, to a modified polypropylene in which an ultra high crystalline olefin resin, a polyolefin elastomer, an unsaturated carboxylic acid, or an anhydride thereof is grafted. The present invention relates to a polyolefin resin composition having excellent metallic luster including a resin, talc, and an aluminum pigment, and a molded article produced using the same.

Description

Polyolefin resin composition excellent in metallic luster and a molded article manufactured therefrom {THE POLYOLEFIN COMPOSITION WITH IMPROVED METAL-GLOSS AND A PRODUCT MANUFACTURED USING THE SAME}

The present invention relates to a polyolefin resin composition having excellent metallic luster and a molded article manufactured using the same, and more particularly, to a modified polypropylene in which an ultra high crystalline olefin resin, a polyolefin elastomer, an unsaturated carboxylic acid, or an anhydride thereof is grafted. The present invention relates to a polyolefin resin composition having excellent metallic luster and a molded article prepared using the resin, talc, and aluminum pigment.

Polypropylene has been widely used in various fields because of its relatively stable price, light weight and mechanical strength. However, there is a problem of poor impact resistance and rigidity, and for the purpose of improving such a problem, a polypropylene resin composition prepared by adding an inorganic filler such as ethylene-propylene copolymer rubber (EPM) and talc has been proposed, and in particular, such a poly The molded article made of the propylene resin composition is used after being molded into a final product after performing a coating process after molding in consideration of appearance.

However, polypropylene has a non-polar group in the molecule, which is chemically inert and extremely poor in paintability, and thus, a method of improving the paintability by various methods has been a factor of cost increase for the resin composition.

In addition, the wheel cover of a conventional automobile is produced by press molding of steel sheets, but nylon or polyphenylene oxide, which is excellent in heat resistance, is used for weight reduction and cost reduction, and in recent years, from the viewpoint of cost reduction, reinforced resin of polyolefin such as polypropylene The composition is used, and various proposals are made.

For example, a resin composition characterized by containing a highly crystalline polypropylene resin, a polyolefin elastomer, a resin modified with an unsaturated carboxylic acid or a derivative thereof, and talc having an average particle diameter of 10 µm or less.

Japanese Patent Laid-Open No. 5-20561 discloses a wheel cover material made of glass fiber surface treated with a polypropylene resin and an organosilane compound. Components, such as talc, may be contained in polypropylene resin, and maleic anhydride modified polypropylene may be contained.

In addition, Japanese Patent Application Laid-open No. Hei 6-80839 discloses a wheel cover produced by injection molding from a fiber-reinforced polypropylene resin composition containing polypropylene with polypropylene and carboxyl group, silane-treated glass fiber and polyethylene wax. .

In addition, Japanese Patent Application Laid-open No. Hei 10-44701 discloses a wheel cover resin containing 40 to 90 parts by weight of a crystalline propylene-ethylene block copolymer, a polypropylene resin modified with an ethylene-propylene copolymer rubber, an unsaturated carboxylic acid or a derivative thereof, and an average particle diameter. The glass fiber reinforced resin composition which contains this 10 micrometers or less talc and glass fiber is proposed.

However, the polypropylene resin composition for the wheel cover has a problem that must be subjected to a coating process in order to be applied as a final product, the surface of the product due to the problem of the gloss and the texture of the product falls when used directly without the coating process This has the disadvantage of being damaged, and also has problems with recycling and recycling of the paint.

In order to improve the above problems, Japanese Patent Application Laid-Open No. 8-239527 proposes a resin composition in which aluminum flakes, metal powder pigments and pearl pigments are mixed with a resin composition composed of a high crystalline polypropylene resin, a polyolefin elastomer, a modified resin and a talc. Doing. However, the resin composition solved the problem of the metal texture and gloss of the product when applied to the side mold, side garnish and bumper corner of the car, but when used in a product that generates a large amount of weld lines, such as car wheel covers and chairs, There is a problem in that weld lines are generated due to the nonuniformity of dispersibility of the aluminum pieces and the metal pigment in the composition.

The present invention is to solve the problems of the prior art as described above, the object of the present invention is to have excellent mechanical properties such as strength, impact resistance, heat resistance and rigidity, there is no molding failure during injection molding of the molded article, molding of the molded article There is no after-painting process to reduce the processing cost can be seen to reduce the cost, in particular, less generation of weld lines, to provide a polyolefin resin composition having excellent gloss and metal texture and molded articles produced using the same.

Polyolefin resin composition excellent in metallic luster according to the present invention is a modified polypropylene resin 1 to 40 to 65% by weight of ultra high crystalline olefin resin, 5 to 25% by weight polyolefin elastomer, unsaturated carboxylic acid or anhydride thereof It is characterized in that it comprises 10% by weight, talc 5-30% by weight and 2-8% by weight of aluminum pigment pigment. If the content of all components is out of the above range, the physical properties suitable for the application is not expressed.

The melt index of the ultrahigh crystalline olefin resin used in the present invention is preferably 20 to 80 g / 10 minutes (ASTM D1238, 230 ° C), and particularly preferably 30 to 60 g / 10 minutes. Ultra high crystalline olefin resins are particularly limited to resins having an isotactic peptide content of 96% or more by the C-NMR method of the homo-part, and their role is to improve the flowability of the polyolefin elastomer, and to improve heat resistance, rigidity and thermal deformation. Increase If the isotactic peptide portion of the homo portion is less than 96%, mechanical properties such as strength, impact resistance, heat resistance and rigidity of the olefin resin are lowered, and heat resistance and rigidity of a molded article such as a wheel cover obtained are lowered. If the content of the ultra high crystalline olefin resin is less than 40% by weight, the effect of improving the flowability of the polyolefin elastomer is insufficient. If the content is more than 65% by weight, it may adversely affect other physical properties.

The ultrahigh crystalline olefin resin is, for example, isotactic polypropylene homopolymer, propylene-ethylene copolymer, propylene-1-butene copolymer, propylene-1-hexene copolymer, propylene-4-methyl-1-pentene Block copolymers, random copolymers or mixtures thereof of propylene with small amounts of other alpha olefins such as copolymers are preferred.

The polyolefin-based elastomer used in the present invention imparts elastic properties, and exhibits elasticity and flexibility. It is preferable that the pattern viscosity (ML1 + 4, 100 ° C.) is 10 to 100, especially 20 to 80, and when the pattern viscosity is less than 10, the flowability is improved, but the mechanical properties are lowered. It improves, but the flowability decreases, making molding difficult. If the content of the polyolefin elastomer is less than 5% by weight, elasticity and flexibility are insufficient, and if the content of the polyolefin elastomer exceeds 25% by weight, the flowability is deteriorated.

The polyolefin elastomers include ethylene propylene copolymer rubber, ethylene propylene dicyclopentadiene rubber, ethylene propylene-1,4-hexadiene rubber, ethylene propylene cyclopentadiene rubber, ethylene propylene methylene norbornene rubber, ethylene propylene ethylidene norbornene Rubber, ethylene butadiene copolymer rubber, and ethylene octadiene copolymer rubber are preferred.

In addition, polyolefin elastomers include hydrogenated styrene-butadiene block copolymer (SEBS), hydrogenated styrene butadiene rubber (HSBR), styrene-ethylene-butylene block copolymer (SEBC) and crystalline ethylene- which are thermoplastic elastomer resins. Butylene block copolymer (CEBC) etc. can also be used. When the thermoplastic elastomer resin and the ultrahigh crystalline olefin resin are mixed, the impact resistance is improved.

The content of the comonomer in the polyolefin elastomer is preferably 10 to 40% by weight, particularly 20 to 30% by weight.

The modified polypropylene resin grafted with unsaturated carboxylic acid or anhydride thereof used in the present invention is used to improve impact resistance and heat resistance through improved adhesion to the talc interface of the resin composition, and the production of the modified polypropylene resin is usually It can be carried out by melt kneading method of, for example, crystalline polypropylene and unsaturated carboxylic acid or its anhydride and catalyst can be added to a twin screw extruder and heated and melted at a temperature of 180 ~ 220 ℃. If the content of the modified polypropylene resin is less than 1% by weight, the effect of improving the adhesiveness with talc is insufficient. If the content of the modified polypropylene resin is greater than 10% by weight, other physical properties may be affected.

The talc used in the present invention has an average particle diameter of 5 µm or less, preferably 1 to 4 µm, by laser diffraction scattering. When the average particle diameter of talc exceeds 5 micrometers, a specific surface area cannot be enlarged enough, and the hardness and impact resistance of a composition fall.

It is preferable to use 5-30 weight%, and, as for the talc used for improving mechanical rigidity and heat resistance, it is more preferable to use 20-30 weight%. If less than 5% by weight of the mixture does not have an effect on the improvement of heat resistance, and more than 30% by weight of the mixture lowers the weight and impact resistance.

The aluminum pigment used in the present invention is a pigment pigment comprising a piece of aluminum having a different particle size, that is, a particle average size of 50 ~ 100㎛ and a pigment pigment containing an aluminum piece having a particle average size of 100 ~ 180㎛. It is characterized in that the pigment is a color pigment comprising a piece of color pigments or bimodal (bimodal) having a size distribution of 60 ~ 140㎛ average composition of the composition in a weight ratio of 4: 1 to 1: 4.

The aluminum tint pigment of the metal texture shows the same metal texture and glossiness as the coated product after molding the product, and also shows the effect that no weld lines are generated, less damage due to external impact, and improve the appearance quality. Used for the purpose. That is, in the present invention, by using a pigment pigment containing aluminum pieces having different particle sizes as described above, or using pigment pigments containing aluminum pieces having a bimodal particle size distribution, metal texture and weld line generation problems are solved. It can be improved at the same time. Welded when the weight ratio of the pigmented pigment containing aluminum pieces having a particle average size of 50 to 100 μm and the pigmented pigment containing aluminum pieces having a particle average size of 100 to 180 μm is outside the range of 4: 1 to 1: 4. This can cause line generation, which can be undesirable.

Production of aluminum pigment pigments is carried out by a conventional melt kneading method, the composition of which is, for example, 40 to 55% by weight of crystalline polypropylene, 7 to 15% by weight of aluminum pieces surface treated with modified silicone or silane compound, etc., mica and 15 to 20% by weight of inorganic materials such as silica, 5 to 10% by weight of dispersant for improving the dispersibility of inorganic materials, 0.1 to 1% by weight of pigment for coloring to form color and 0.1 to 0.3% by weight of beta crystal forming nucleating agent required for beta crystallization It is preferable to comprise%. In this case, the particle size of the aluminum pieces is based on the particle size after the surface treatment.

In particular, the nucleating agent for forming beta crystals required for the beta crystallization of a pigment is a group IIA metal salt of the periodic table of the carboxylic acid, and calcium salt of dicarboxylic acid is particularly preferable.

In the aluminum pigment pigment, by using the aluminum pieces surface-treated with organic materials such as modified silicon or silane compound as described above, the aluminum pieces can form a good dispersed phase in the weld dry area, thereby reducing the generation of weld lines. In addition, by using a beta crystal forming nucleating agent, beta crystals are formed at the weld line generation site, thereby minimizing the weld line. If the content of the aluminum pigment pigment is less than 2% by weight, the metal texture and gloss imparting effect is insufficient, and if the content of more than 8% by weight may affect other mechanical properties of the composition is not preferable.

In the composition of the present invention, various additives, reinforcing materials, fillers, for example, heat stabilizers, weather stabilizers, antistatic agents, lubricants, slip agents (SLIP), nucleating agents, flame retardants, wollastonite, calcium carbonate, mica, kaolin, clay, barium sulfate , Calcium sulfate or the like can be added within a range not inconsistent with the object of the present invention.

The molded article of the present invention may be manufactured by molding the polyolefin resin composition as described above into a side mold, a side garnish, a bumper corner, a wheel cover, an office chair, etc. of an automobile.

The present invention can be understood in more detail by the following examples and comparative examples, the following examples are merely examples for illustrating the present invention, and are not intended to limit the protection scope of the present invention.

[Examples and Comparative Examples]

In the examples and comparative examples, the symbol means the following contents.

1) Olefin Resin

PP-1: Melt Index 55g / 10min (230 ℃), Ethylene Unit Content 5mol%,

       Isotactic peptide fraction by C-NMR method is less than 96%

PP-2: melt index 60g / 10min (230 ℃), ethylene unit content 7mol%,

              96% or more of isotactic peptide by C-NMR method

PP-3: Melt Index 25g / 10min (230 ℃), Ethylene Unit Content 3mol%,

              96% or more of isotactic peptide by C-NMR method

2) Polyolefin Elastomer (EPM)

EP-1: ethylene-propylene copolymer rubber, pattern viscosity (ML1 + 4 100 ° C.) 24,

              Propylene content 26 wt%

EP-2: ethylene-propylene copolymer rubber, pattern viscosity (ML1 + 4 100 ° C.) 70,

              Propylene Content 27% By Weight

EP-3: Ethylene-butadiene copolymer rubber, pattern viscosity (ML1 + 4 100 ° C) 44

              Butadiene content 20% by weight

EP-4: ethylene-octadiene copolymer rubber, pattern viscosity (ML1 + 4 100 ° C) 35,

              Octadiene content 25% by weight

3) Modified Polypropylene Resin

CP: modified polypropylene resin grafted with maleic anhydride (modification ratio = 0.4)

4) Talc

TALC-1: Average particle size 4㎛

TALC-2: Average particle size 8㎛

5) Toning Pigment

CPG-1: A bath containing aluminum chips with a mean particle size of 70 µm after surface treatment

        Color pieces and aluminum particles with a mean particle size of 170 µm after surface treatment

        Color pigments containing 2: 3 ratio of pigments

        %, 15% by weight flakes of aluminum, 20% inorganic

        %, 9 weight% of dispersant, 0.7 weight% of pigment for color, 0.3 weight% of nucleating agent)

CPG-2: A bath containing a piece of aluminum having a particle average size of 90 µm after surface treatment

        Color pigment (50% by weight of polypropylene, aluminum surface-treated with silane compound

        Flakes 20%, Mineral 20%, Dispersant 9%, Color Pigment 0.7

        Wt%, 0.3 wt% of nucleating agent)

A predetermined amount of each component shown in Table 1 was collectively added to the kneading extruder to prepare a resin composition after kneading. Both Examples and Comparative Examples were dried for 2 hours in an 80 ℃ oven in consideration of the weakening of the physical properties by moisture absorption in the composition. Using this composition, Samsung Kleukner FCM-110 (molding force = 110 tons) injection machine, the injection temperature is 30/200/200/200/200 ℃ in order from the feeding hopper to the nozzle, the mold temperature is 60 ℃, injection pressure is Injection molded at 60 to 100 bar to prepare a molded article for measuring the physical properties and a test piece for the appearance test.

Measurement of physical properties of each Example and Comparative Example was carried out by the following test method.

(1) Flexural modulus (MPa): ASTM D790

(2) IZOD impact strength (Kgcm / cm): ASTM D256

(3) Heat deflection temperature (℃) (heat resistance test): ASTM D656,

    (Circle): 134 degreeC or more, (triangle | delta): 127-133 degreeC, x: 126 degrees C or less

(4) Falling impact strength: Breaking due to spontaneous drop of 500g weight at low temperature (-30 ℃)

                   Phase judgment (low temperature falling test)

(5) Appearance judgment: visual inspection on the gloss and metallic texture of products coated after molding

               Judgment

(6) Weld line: Weld line generation degree for molded product

    ○: less than 2 mm, △: 2 to 5 mm, ×: more than 5 mm

(7) Scratch resistance: diamond hardness

○: scratch width 0.10 mm or less, △: scratch width 0.11 to 0.50 mm,

×: 0.51mm or more

The polyolefin resin compositions of Examples 1 to 3 have good stiffness, excellent impact resistance, heat resistance and falling impact strength, excellent appearance, and in particular, fewer weld lines in the product.

The polyolefin resin composition of Comparative Example 1 has excellent stiffness and impact resistance, but generates weld lines and is poor in scratch resistance.

The polyolefin resin composition of Comparative Example 2 has low rigidity, impact resistance, and heat resistance, weld lines are generated, and appearance and scratch resistance are slightly poor.

In the polyolefin resin composition of Comparative Example 3, weld lines are generated, and appearance and scratch resistance are slightly poor.

As can be seen from the above examples and comparative examples, the polyolefin resin composition prepared by the present invention has excellent mechanical properties such as strength, impact resistance, heat resistance and rigidity, and there is no molding defect during injection molding of a molded article, Since there is no coating process after molding the molded product, the processing cost can be lowered and the cost can be reduced, and it has excellent gloss and metal texture, and in particular, less generation of weld lines.

Claims (7)

40 to 65% by weight of ultra high crystalline olefin resin having an isotactic peptide content of 96% or more, 5 to 25% by weight of polyolefin elastomer, 1 to 10% by weight of modified polypropylene resin grafted with unsaturated carboxylic acid or its anhydride, It comprises 5 to 30% by weight of talc and 2 to 8% by weight of aluminum pigment, wherein the aluminum pigment is an aluminum pigment and an average particle size of 100, including an aluminum piece having a particle average size of 50 ~ 100㎛. Toning pigment comprising a piece of aluminum of ~ 180㎛ comprises a color pigment having a weight ratio of 4: 1 to 1: 4 or an aluminum piece having a bimodal size distribution of the average particle size of 60 ~ 140㎛ Polyolefin resin composition excellent in metallic luster, characterized in that it is a pigment pigment. The melt index of the ultrahigh crystalline olefin resin according to claim 1 is 20 to 80 g / 10 minutes (ASTM D1238, 230 ° C), and isotactic polypropylene homopolymer, propylene-ethylene copolymer, and propylene-1-butene It is a copolymer, a propylene-1-hexene copolymer, a propylene-4-methyl-1- pentene copolymer, or a mixture thereof, The polyolefin resin composition excellent in the metallic glossiness characterized by the above-mentioned. The polyolefin resin of claim 1, wherein the polyolefin-based elastomer has a pattern viscosity (ML1 + 4,100 ° C) of 10 to 100 and a comonomer content of 10 to 40% by weight in the elastomer. Composition. The polyolefin resin composition having excellent metallic glossiness according to claim 1, wherein the talc has an average particle diameter of 5 µm or less by laser diffraction scattering. According to claim 1, wherein the aluminum pigment pigment is 40 to 55% by weight of crystalline polypropylene, 7 to 15% by weight of aluminum pieces surface-treated with a modified silicone or silane compound, 15 to 20% by weight inorganic material, dispersant 5 to 10 A polyolefin resin composition having excellent metallic glossiness, comprising: by weight, 0.1-1% by weight of pigment for color, and 0.1-0.3% by weight of beta crystal forming nucleating agent. The polyolefin resin composition having excellent metal glossiness according to claim 5, wherein the beta crystal forming nucleating agent is a calcium salt of dicarboxylic acid. A molded article obtained by injection molding the polyolefin resin composition according to any one of claims 1 to 6.