Polypropylene resin composition and molded articles manufactured therefrom

Abstract

The polypropylene resin composition of the present invention is characterized by comprising approximately 100 parts by weight of polypropylene resin; approximately 5 to 15 parts by weight of styrene-based thermoplastic elastic material; approximately 2 to 5 parts by weight of zinc oxide; approximately 0.1 to 0.7 parts by weight of silver-based compound; approximately 15 to 35 parts by weight of talc; and approximately 1 to 5 parts by weight of carbon fiber. The polypropylene resin composition is excellent in antibacterial properties, antifungal properties, antiviral properties, impact resistance, rigidity, thermal stability, and the balance of these physical properties, and has a melange-like texture, a fibrous texture, etc.

Description

[Technical Field]

[0001] This invention relates to a polypropylene resin composition and molded articles manufactured therefrom. More specifically, this invention relates to a polypropylene resin composition and molded articles manufactured therefrom that have excellent antibacterial, antifungal, antiviral, impact resistance, rigidity, thermal stability, and balance of these physical properties, and that have a melange-like texture. [Background technology]

[0002] Since the COVID-19 pandemic, there has been an increased demand for thermoplastic resin products that include antibacterial, antifungal, and antiviral properties. Along with this, there is a need for improved appearance characteristics for applications such as automotive interior materials.

[0003] Polypropylene resin is a material that excels in chemical resistance, weather resistance, and processability, and is easily manufactured into injection molded products, films, and blow molded products. It is widely used in fields such as electrical components, automobiles, and building materials.

[0004] Copper (Cu) compounds are widely known as materials used to impart antibacterial, antifungal, and antiviral properties to such resins. However, when copper compounds are applied to thermoplastic resin compositions, processing is difficult, and problems such as discoloration due to reduced thermal stability and limitations in colorability exist, severely limiting the range of products to which they can be applied.

[0005] Therefore, there is a need to develop polypropylene resin compositions that excel in antibacterial, antifungal, antiviral, impact resistance, rigidity, thermal stability, and the balance of these physical properties, as well as having a melange-like texture (a soft-toned texture with two or more colors mixed together) or a fibrous texture for improved appearance.

[0006] The background technology of this invention is disclosed in Korean Patent Application Publication No. 10-2020-0065139, among others. [Overview of the project] [Problems that the invention aims to solve]

[0007] The object of the present invention is to provide a polypropylene resin composition that is excellent in antibacterial properties, antifungal properties, antiviral properties, impact resistance, rigidity, thermal stability, and the balance of these physical properties, and has a melange-like texture, a fibrous texture, etc.

[0008] Another object of the present invention is to provide a molded article formed from the polypropylene resin composition.

[0009] All of the above-mentioned and other objectives of the present invention can be achieved by the present invention as described below. [Means for solving the problem]

[0010] 1. One aspect of the present invention relates to a polypropylene resin composition. The polypropylene resin composition comprises about 100 parts by weight of polypropylene resin; about 5 to 15 parts by weight of styrene-based thermoplastic elastic material; about 2 to 5 parts by weight of zinc oxide; about 0.1 to 0.7 parts by weight of silver-based compound; about 15 to 35 parts by weight of talc; and about 1 to 5 parts by weight of carbon fiber.

[0011] 2. In the specific example described in (1) above, the polypropylene resin may include one or more of homopolypropylene resin, block polypropylene resin, and random polypropylene resin.

[0012] 3. In the specific examples described in 1 or 2 above, the polypropylene resin may have a melt-flow index of approximately 10 g / 10 min to approximately 110 g / 10 min, measured under the conditions of 230°C and a 2.16 kg load, based on ASTM D1238.

[0013] 4. In the specific examples 1 to 3 above, the styrene-based thermoplastic elastic material may include one or more of the following: styrene-ethylene / butylene-styrene (SEBS) copolymer, styrene-ethylene-butylene (SEB) copolymer, styrene-butadiene-styrene (SBS), and styrene-isoprene-styrene (SIS).

[0014] 5. In the specific examples 1 to 4 above, the styrene-based thermoplastic elastic material may have a weight-average molecular weight of approximately 50,000 g / mol to approximately 120,000 g / mol.

[0015] 6. In the specific examples 1 to 5 above, the zinc oxide may have an average particle size of about 0.7 μm to about 1.5 μm, and a specific surface area BET of about 1 m². 2 / g to approx. 7m 2 / g is also acceptable.

[0016] 7. In the specific examples described in 1 to 6 above, the silver-based compound may include one or more carriers from among metallic silver, silver oxide, silver halide, and silver ions.

[0017] 8. In the specific examples 1 to 7 above, the polypropylene resin composition may further contain polyethylene resin.

[0018] 9. In the specific examples 1 to 8 above, the polypropylene resin composition may have an antimicrobial activity value of approximately 2 to approximately 7, measured after inoculating a 5 cm x 5 cm test piece with Staphylococcus aureus and Escherichia coli, and culturing it for 24 hours at 35°C and RH90%, based on the antimicrobial evaluation method of JIS Z 2801-1.

[0019] 10. In the specific examples 1 to 9 above, the polypropylene resin composition may have an antifungal rating of 0 to 2, measured after inoculating a 5 cm × 5 cm injection-molded test piece with mold spores and culturing it for 28 days at 29°C and RH95% based on the ISO 846:2019-A evaluation method.

[0020] 11. In the above specific examples 1 to 10, the polypropylene resin composition may have an antiviral activity value of about 2 to about 7 when a test piece with a size of 5 cm × 5 cm is dropped with an influenza A virus (H3N2): ATCC VR-1679 virus solution and exposed to the virus for 24 hours under the conditions of 25 °C and RH 50% and then measured based on the ISO 21702:2019 evaluation method.

[0021] 12. In the above specific examples 1 to 11, the polypropylene resin composition has a notched Izod impact strength of about 4 kJ / m 2 to about 12 kJ / m 2 for a 4-mm-thick test piece measured based on ISO 180.

[0022] 13. In the above specific examples 1 to 12, the polypropylene resin composition may have a tensile strength of about 20 MPa to about 30 MPa for a 4-mm-thick test piece measured under the condition of 50 mm / min based on ISO 527, and may have a flexural strength of about 30 MPa to about 42 MPa for a 4-mm-thick test piece measured under the condition of 2 mm / min based on ISO 178, and may have a flexural modulus of about 1,800 MPa to about 2,700 MPa for a 4-mm-thick test piece measured under the condition of 2 mm / min based on ISO 178.

[0023] 14. In the above specific examples 1 to 11, the polypropylene resin composition may have a heat distortion temperature (HDT) of about 1*06 °C to about 120 °C for a **4-mm-thick test piece measured under the conditions of 0.45 MPa and a temperature increase rate of 120 °C / hr based on ISO 75.

[0024] 15. Another aspect of the present invention relates to a molded article. The molded article is characterized by being formed from the polypropylene resin composition according to any one of the above 1 to 14.

Advantages of the Invention

[0025] It should be noted that there seems to be a small error in the original text where "1*06 °C" and "**4-mm-thick" are likely typos. I translated them as they are but they might need to be corrected in the original context.The present invention provides a polypropylene resin composition and molded articles formed therefrom that have excellent antibacterial, antifungal, antiviral, impact resistance, rigidity, thermal stability, and balance of these physical properties, as well as a melange-like texture and a fibrous texture. [Modes for carrying out the invention]

[0026] The present invention will be described in detail below.

[0027] The polypropylene resin composition according to the present invention comprises (A) polypropylene resin; (B) styrene-based thermoplastic elastomer; (C) zinc oxide; (D) silver-based compound; (E) talc; and (F) carbon fiber.

[0028] In this specification, the numerical range "a to b" is defined as "≥ a and ≤ b".

[0029] (A) Polypropylene resin A specific example of the present invention involves a polypropylene resin that can be applied together with styrene-based thermoplastics, zinc oxide, silver compounds, talc, and carbon fibers to improve the antibacterial, antifungal, antiviral, impact-resistant, rigid, and thermal stability properties of the polypropylene resin composition, as well as the balance of these properties, and which has a melange-like texture, a fibrous texture, etc. It may also be a polypropylene resin that can be applied to ordinary thermoplastic resin compositions.

[0030] In specific examples, the polypropylene resin may include homopolypropylene resin, block polypropylene resin, random polypropylene resin, or combinations thereof. Here, the block polypropylene resin may be a block polypropylene resin composed of homopolypropylene blocks, ethylene-propylene copolymer blocks, and / or homopolyethylene blocks, and the random polypropylene resin may be a propylene-ethylene random copolymer. For example, the polypropylene resin may be a block polypropylene resin.

[0031] In a specific example, the polypropylene resin may have a melt flow index (MI) of approximately 10 g / 10 min to approximately 110 g / 10 min, for example, approximately 15 g / 10 min to approximately 95 g / 10 min, measured under conditions of 230°C and a 2.16 kg load, based on ASTM D1238. Within this range, the mechanical properties and moldability of the polypropylene resin composition may be excellent.

[0032] (B) Styrene-based thermoplastic elastomer A styrene-based thermoplastic elastomer according to one specific example of the present invention is applied to a polypropylene resin together with zinc oxide, silver compounds, talc, and carbon fibers, improving the antibacterial, antifungal, antiviral, impact resistance, rigidity, thermal stability, and balance of these physical properties of the polypropylene resin composition, and having a melange-like texture, a fibrous texture, etc. It may also be a styrene-based thermoplastic elastomer used in ordinary thermoplastic resin compositions.

[0033] In specific examples, the styrene-based thermoplastic elastic material may include styrene-ethylene / butylene-styrene (SEBS) copolymer, styrene-ethylene-butylene (SEB) copolymer, styrene-butadiene-styrene (SBS), styrene-isoprene-styrene (SIS), and combinations thereof.

[0034] In a specific example, the styrene-based thermoplastic elastic material may have a weight-average molecular weight measured by gel permeation chromatography (GPC) of approximately 50,000 g / mol to approximately 120,000 g / mol, for example, approximately 55,000 g / mol to approximately 110,000 g / mol. Within this range, the mechanical properties of the polypropylene resin composition, such as room temperature impact resistance and low-temperature impact resistance, can be excellent.

[0035] In specific examples, the styrene-based thermoplastic elastomer may be included in an amount of about 5 to about 15 parts by weight, for example, about 6 to about 12 parts by weight, per about 100 parts by weight of the polypropylene resin. If the content of the styrene-based thermoplastic elastomer is less than about 5 parts by weight per about 100 parts by weight of the polypropylene resin, the impact resistance (room temperature impact resistance, low temperature impact resistance, etc.) of the polypropylene resin composition may decrease, and if it exceeds about 15 parts by weight, the rigidity, thermal stability, etc. of the polypropylene resin composition may decrease.

[0036] (C) Zinc Oxide A specific example of the present invention involves applying zinc oxide to a polypropylene resin together with a styrene-based thermoplastic elastomer, a silver-based compound, talc, and carbon fibers, thereby improving the antibacterial, antifungal, antiviral, impact-resistant, rigid, and thermal stability properties of the polypropylene resin composition, as well as the balance of these physical properties, and providing a melange-like texture, a fibrous texture, etc. It may also be zinc oxide used in ordinary thermoplastic resin compositions.

[0037] In a specific example, the zinc oxide may have an average particle size (D50) of approximately 0.7 μm to approximately 1.5 μm, measured using a particle size analyzer (Beckman Coulter, equipped with a laser diffraction particle size distribution analyzer LS 13 320) in accordance with ISO 13320-1. Furthermore, the zinc oxide may have a specific surface area BET of approximately 1 m², measured using a BET analysis system (Micromeristics, equipped with a specific surface area and pore size distribution analyzer ASAP 2020) in accordance with ASTM C 1251:95 using the nitrogen gas adsorption method. 2 / g to approx. 7m 2 The density may be as low as / g, and the purity may be approximately 99% or higher. Within this range, the polypropylene resin composition may exhibit excellent antibacterial, antifungal, and antiviral properties.

[0038] In specific examples, the zinc oxide may be present in an amount of about 2 to 5 parts by weight, for example, about 3 to 4.5 parts by weight, per about 100 parts by weight of the polypropylene resin. If the zinc oxide content is less than about 2 parts by weight per about 100 parts by weight of the polypropylene resin, the antibacterial, antifungal, and antiviral properties of the polypropylene resin composition may decrease, and if it exceeds about 5 parts by weight, the impact resistance of the polypropylene resin composition may decrease.

[0039] (D) Silver-based compound A specific example of the present invention involves a silver (Ag)-based compound applied to a polypropylene resin together with a styrene-based thermoplastic elastomer, zinc oxide, talc, and carbon fibers, thereby improving the antibacterial, antifungal, antiviral, impact-resistant, rigid, thermal-stable, and balance-of-the-physical-properties of the polypropylene resin composition, resulting in a melange-like texture and a fibrous texture. The silver-based compound is not particularly limited as an antibacterial agent as long as it contains a silver component, and can include, for example, metallic silver, silver oxide, silver halide, a carrier containing silver ions, or combinations thereof. Of these, a carrier containing silver ions can be used. Examples of such carriers include zeolite, silica gel, calcium phosphate, zirconium phosphate, sodium zirconium phosphate, and sodium hydrogen zirconium phosphate. The carrier is preferably porous. A porous carrier can retain the silver component inside, thereby increasing the silver content and improving the sustained performance (maintenance) of the silver component. Specifically, silver sodium hydrogen zirconium phosphate can be used as the silver-based compound.

[0040] In a specific example, the silver-based compound may have an average particle size (D50) of approximately 15 μm or less, measured using a particle size analyzer (equipped with a Beckman Coulter LS 13 320 laser diffraction particle size distribution analyzer), for example, approximately 0.1 μm to approximately 12 μm.

[0041] In a specific example, the silver-based compound may be included in an amount of about 0.1 to about 0.7 parts by weight, for example, about 0.1 to about 0.5 parts by weight, per about 100 parts by weight of the polypropylene resin. If the content of the silver-based compound is less than about 0.1 parts by weight per about 100 parts by weight of the polypropylene resin, the antiviral properties of the polypropylene resin composition may decrease, and if it exceeds about 0.7 parts by weight, the impact resistance of the polypropylene resin composition may decrease.

[0042] In specific examples, the weight ratio of zinc oxide to the silver-based compound may be about 1:0.02 to about 1:0.15, for example, about 1:0.025 to about 1:0.134. Within this range, the antibacterial, antifungal, antiviral, and mechanical properties of the polypropylene resin composition may be further improved.

[0043] (E) Talc A specific example of the present invention involves applying talc to a polypropylene resin together with a styrene-based thermoplastic elastomer, zinc oxide, silver-based compounds, and carbon fibers, thereby improving the antibacterial, antifungal, antiviral, impact-resistant, rigid, and thermal stability properties of the polypropylene resin composition, as well as the balance of these physical properties, and having a melange-like texture, a fibrous texture, etc. It may also be a plate-type talc used in ordinary thermoplastic resin compositions.

[0044] In a specific example, the talc may have an average particle size of approximately 3 μm to approximately 10 μm, for example, approximately 4 μm to approximately 6 μm, as measured by a particle size analyzer (Malvern Panalytical, Mastersizer 3000). Within this range, the tensile strength, flexural strength, and other properties of the polypropylene resin composition can be excellent.

[0045] In specific examples, the talc may be included in an amount of about 15 to about 35 parts by weight, for example, about 20 to about 30 parts by weight, per about 100 parts by weight of the polypropylene resin. If the talc content is less than about 15 parts by weight per about 100 parts by weight of the polypropylene resin, the rigidity, thermal stability, etc. of the polypropylene resin composition may decrease, and if it exceeds about 35 parts by weight, the impact resistance, etc. of the polypropylene resin composition may decrease.

[0046] (F) Carbon fiber A carbon fiber according to one specific example of the present invention is applied to a polypropylene resin together with a styrene-based thermoplastic elastomer, zinc oxide, a silver-based compound, and talc, etc., to improve the antibacterial, antifungal, antiviral, impact-resistant, rigid, thermal stability, and balance of these physical properties of the polypropylene resin composition, and has a melange-like texture, a fibrous texture, etc., and may be a carbon fiber used in ordinary thermoplastic resin compositions.

[0047] In a specific example, the carbon fibers may have an average diameter of approximately 10 μm to approximately 25 μm, for example, approximately 16 μm to approximately 20 μm, as measured by an optical microscope, and an average length of approximately 0.1 mm to approximately 2 mm, for example, approximately 0.5 mm to approximately 1.5 mm. Within this range, the rigidity of the polypropylene resin composition can be excellent, and a melange-like texture, fiber-like texture, etc., can be imparted to the polypropylene resin composition and molded article.

[0048] In specific examples, the carbon fibers may be included in an amount of about 1 to about 5 parts by weight, for example, about 1.5 to about 3 parts by weight, per about 100 parts by weight of the polypropylene resin. If the carbon fiber content is less than about 1 part by weight per about 100 parts by weight of the polypropylene resin, the melange-like texture may not be sufficiently realized in the appearance of the polypropylene resin composition, and if it exceeds about 5 parts by weight, the impact resistance of the polypropylene resin composition may decrease, and an excessive foreign body appearance may be expressed.

[0049] (G) Polyethylene resin A polypropylene resin composition according to one specific example of the present invention may further contain polyethylene resin. As the polyethylene resin, ordinary polyethylene resins (such as low-density polyethylene (LDPE), medium-density polyethylene (MDPE), high-density polyethylene (HDPE), linear low-density polyethylene (LLDPE)), bio-polyethylene resins, or combinations thereof can be used. When the polyethylene resin is applied, the impact resistance and appearance characteristics (such as gloss) of the polypropylene resin composition can be further improved. Here, the bio-polyethylene resin refers to an environmentally friendly product made by distilling / dehydrating / polymerizing ethyl alcohol in sugarcane residue remaining after sugar extraction.

[0050] In a specific example, the polyethylene resin may have a melt flow index (MI) of approximately 20 g / 10 min to approximately 40 g / 10 min, for example, approximately 23 g / 10 min to approximately 32 g / 10 min, measured under conditions of 230°C and a 2.16 kg load, based on ASTM D1238. Within this range, the impact resistance and appearance characteristics of the polypropylene resin composition can be excellent.

[0051] In a specific example, when the polyethylene resin is applied, its content may be about 10 to 25 parts by weight, for example, about 11 to 20 parts by weight, per about 100 parts by weight of the polypropylene resin. Within this range, the impact resistance, appearance characteristics, etc., of the polypropylene resin composition may be further improved.

[0052] A polypropylene resin composition according to one specific example of the present invention may further contain additives that are typically found in thermoplastic resin compositions. Examples of such additives include, but are not limited to, antioxidants, flame retardants, anti-dripping agents, UV stabilizers, mold release agents, nucleating agents, pigments, dyes, and mixtures thereof.

[0053] In a specific example, when using the additive, its content may be about 0.001 to about 40 parts by weight, for example, about 0.01 to about 10 parts by weight, based on about 100 parts by weight of the polypropylene resin.

[0054] The polypropylene resin composition according to a specific example of the present invention may be in the form of pellets obtained by mixing the above components and melt-extruding at about 170°C to about 240°C, for example, about 190°C to about 230°C, using an ordinary twin-screw extruder.

[0055] In a specific example, the polypropylene resin composition is inoculated with Staphylococcus aureus and Escherichia coli on a test piece with a size of 5 cm × 5 cm based on the JIS Z 2801-1 antibacterial evaluation method, cultured for 24 hours under the conditions of 35°C and RH90%, and the measured antibacterial activity values may be about 2 to about 7, for example, about 3 to about 5.

[0056] In a specific example, the polypropylene resin composition is inoculated with mold spores on an injection test piece with a size of 5 cm × 5 cm based on the ISO 846:2019-A evaluation method, cultured for 28 days under the conditions of 29°C and RH95%, and the measured mold resistance grade may be from grade 0 to grade 2.

[0057] In a specific example, the polypropylene resin composition is dropped with influenza A virus (H3N2): ATCC VR-1679 virus solution on a test piece with a size of 5 cm × 5 cm based on the ISO 21702:2019 evaluation method, exposed to the virus for 24 hours under the conditions of 25°C and RH50%, and the measured antiviral activity value may be about 2 to about 7, for example, about 2.1 to about 5.

[0058] In a specific example, the polypropylene resin composition has a notched Izod impact strength of about 4 kJ / m 2 to about 12 kJ / m 2 、for example, about 4 kJ / m 2 to about 10 kJ / m 2That's fine.

[0059] In a specific example, the polypropylene resin composition may have a tensile strength of approximately 20 MPa to approximately 30 MPa, for example, approximately 23 MPa to approximately 28 MPa, when measured at a rate of 50 mm / min according to ISO 527.

[0060] In a specific example, the polypropylene resin composition may have a bending strength of approximately 30 MPa to approximately 42 MPa, for example, approximately 31 MPa to approximately 40 MPa, when measured at a rate of 2 mm / min based on ISO 178.

[0061] In a specific example, the polypropylene resin composition may have a flexural modulus of approximately 1,800 MPa to approximately 2,700 MPa, for example, approximately 1,850 MPa to approximately 2,600 MPa, when measured at a rate of 2 mm / min based on ISO 178.

[0062] In a specific example, the polypropylene resin composition may have a heat distortion temperature (HDT) of a 4 mm thick test specimen measured under ISO 75 conditions of 0.45 MPa and a heating rate of 120 °C / hr, which is approximately 106 °C to approximately 120 °C, for example, approximately 106 °C to approximately 119 °C.

[0063] The molded article according to the present invention is formed from the polypropylene resin composition. The polypropylene resin composition may be manufactured in pellet form, and the manufactured pellets can be produced into a variety of molded articles (products) through a variety of molding methods such as injection molding, extrusion molding, vacuum forming, and casting molding. Such molding methods are well known to those with ordinary skill in the art to which the present invention belongs.

[0064] In specific examples, the molded product is excellent in antibacterial, antifungal, antiviral, impact resistance, rigidity, thermal stability, and the balance of these physical properties, and has a melange-like texture and a fibrous texture, making it useful for automotive interior materials, home appliances, and the like. [Examples]

[0065] The present invention will be described in more detail below through examples, but these examples are for illustrative purposes only and should not be construed as limiting the present invention.

[0066] Examples The specifications of each component used in the examples and comparative examples are as follows:

[0067] (A) Polypropylene resin Block polypropylene resin (ethylene-propylene block copolymer, B-PP, manufacturer: Lotte Chemical, product name: JSS-370N) was used.

[0068] (B) Styrene-based thermoplastic elastomer Styrene-ethylene / butylene-styrene (SEBS) copolymer (manufacturer: Kraton Corporation, product name: G1657) was used.

[0069] (C) Zinc Oxide Zinc oxide (manufacturer: Hanil Chemical, product name: KS-1) was used.

[0070] (D) Silver (Ag)-based compounds Silver phosphate glass (manufacturer: Fuji Chemical Industry Co., Ltd., product name: BM-102SD) was used.

[0071] (E) Talc Talc (manufacturer: Koch, product name: KC-5000CA) was used.

[0072] (F) Carbon fiber It uses carbon fiber (manufacturer: Kureca, product name: KCF-100).

[0073] (G) Polyethylene resin Bio-polyethylene resin (manufacturer: Braschem, product name: SHA7260) was used.

[0074] Examples 1 to 14 and Comparative Examples 1 to 10 Pellet was produced by adding each of the aforementioned components in the amounts listed in Tables 1, 2, 3, and 4 below, and then extruding at approximately 220°C. A twin-screw extruder with an L / D ratio of 36 and a diameter of 45 mm was used for extrusion. The produced pellets were dried at approximately 80°C for at least 2 hours, and then test specimens were produced by injection molding using a 220-ton injection machine (molding temperature: approximately 220°C, mold temperature: approximately 40°C). The physical properties of the produced test specimens were evaluated using the following method, and the results are shown in Tables 1, 2, 3, and 4 below.

[0075] Physical property determination methods (1) Antimicrobial activity evaluation: Based on the antimicrobial evaluation method of JIS Z 2801-1, Staphylococcus aureus and Escherichia coli were inoculated into 5cm x 5cm test pieces, incubated at 35°C and RH90% for 24 hours, and then the antimicrobial activity value was measured.

[0076] (2) Antifungal activity evaluation: Based on the ISO 846:2019-A evaluation method, fungal spores were inoculated into 5cm x 5cm injection-molded test specimens, incubated at 29°C and RH95% for 28 days, and the antifungal activity grade was measured using a microscope.

[0077] (Grade 0: No mold even under a microscope (50x magnification), Grade 1: No mold visible to the naked eye, but clearly visible under a microscope (Grade 1a: No mold visible to the naked eye, but clearly visible under a microscope (less than 25% of the surface of the test piece), Grade 1b: No mold visible to the naked eye, but clearly visible under a microscope (less than 50% of the surface of the test piece), Grade 1c: No mold visible to the naked eye, but clearly visible under a microscope (more than 50% of the surface of the test piece)), Grade 2: Mold clearly visible to the naked eye (less than 25% of the surface of the test piece), Grade 3: Mold clearly visible to the naked eye (less than 50% of the surface of the test piece), Grade 4: Significant mold growth visible to the naked eye (more than 50% of the surface of the test piece), Grade 5: Mold growth covering the entire surface of the test piece is visible to the naked eye.

[0078] (3) Antiviral activity evaluation: Based on the ISO 21702:2019 evaluation method, the polypropylene resin composition was subjected to an influenza A virus (H3N2): ATCC VR-1679 virus solution dropped onto a 5cm x 5cm test piece, exposed to the virus for 24 hours under conditions of 25°C and 50% RH, and then measured for antiviral activity.

[0079] (4) Notched Izod impact strength (unit: kJ / m) 2 The notched Izod impact strength of a 4.0 mm thick test specimen was measured according to ISO 180.

[0080] (5) Tensile strength (unit: MPa): The tensile strength of a 4.0 mm thick test specimen was measured under conditions of 50 mm / min, based on ISO 527.

[0081] (6) Bending strength (unit: MPa): The bending strength of a 4.0 mm thick test specimen was measured under conditions of 2 mm / min, based on ISO 178.

[0082] (7) Flexural modulus (unit: MPa): The flexural modulus of a 4.0 mm thick specimen was measured at a rate of 2 mm / min based on ISO 178.

[0083] (8) Heat distortion temperature (unit: °C): The heat distortion temperature (HDT) of a 4.0 mm thick test specimen was measured under conditions of 0.45 MPa and a heating rate of 120 °C / hr, based on ISO 75.

[0084] [Table 1]

[0085] [Table 2]

[0086] [Table 3]

[0087] [Table 4]

[0088] From the results described above, it was found that the polypropylene resin composition of the present invention is excellent in antibacterial, antifungal, antiviral properties, impact resistance (notched Izod impact strength), rigidity (tensile strength, bending strength, flexural modulus), thermal stability (heat distortion temperature), and balance of these physical properties. Visual evaluation confirmed that it has a melange-like texture and a fibrous texture.

[0089] On the other hand, in Comparative Example 1, where the content of the styrene-based thermoplastic elastomer is less than the range of the present invention, it was found that impact resistance and other properties decreased, and in Comparative Example 2, where the content of the styrene-based thermoplastic elastomer exceeds the range of the present invention, it was found that rigidity, thermal stability, and other properties decreased. In Comparative Example 3, where the content of zinc oxide is less than the range of the present invention, it was found that antibacterial, antifungal, and antiviral properties decreased, and in Comparative Example 4, where the content of zinc oxide exceeds the range of the present invention, it was found that impact resistance and other properties decreased, and in Comparative Example 5, where the content of the silver-based compound is less than the range of the present invention, it was found that antiviral properties decreased, and in Comparative Example 6, where the content of the silver-based compound exceeds the range of the present invention, it was found that impact resistance and other properties decreased. Furthermore, in Comparative Example 7, where the talc content was less than the range of the present invention, it was found that rigidity and thermal stability decreased. In Comparative Example 8, where the talc content exceeded the range of the present invention, it was found that impact resistance decreased. In Comparative Example 9, where the carbon fiber content was less than the range of the present invention, it was confirmed that the melange-like texture could not be sufficiently realized in the appearance. In Comparative Example 10, where the carbon fiber content exceeded the range of the present invention, it was confirmed that impact resistance decreased and an excessive foreign body appearance was expressed.

[0090] The above has described the present invention primarily through its embodiments. Those with ordinary skill in the art to which the present invention pertains will understand that the present invention can be embodied in modified forms that do not depart from its essential characteristics. Therefore, each disclosed embodiment should be considered in an explanatory rather than restrictive manner. The scope of the present invention is defined in the claims, not in the above description, and all differences within an equivalent scope should be interpreted as being included within the scope of the present invention.

Claims

1. Approximately 100 parts by weight of polypropylene resin; Approximately 5 to 15 parts by weight of styrene-based thermoplastic elastic material; Approximately 2 to 5 parts by weight of zinc oxide; About 0.1 part by weight to about 0.7 part by weight of a silver-based compound; Approximately 15 to 35 parts by weight of talc; and A polypropylene resin composition characterized by containing about 1 to about 5 parts by weight of carbon fiber.

2. The polypropylene resin composition according to claim 1, characterized in that the polypropylene resin comprises one or more of homopolypropylene resin, block polypropylene resin, and random polypropylene resin.

3. The polypropylene resin composition according to claim 1, characterized in that the polypropylene resin has a melt flow index of about 10 g / 10 min to about 110 g / 10 min, measured under the conditions of 230°C and a 2.16 kg load, based on ASTM D1238.

4. The polypropylene resin composition according to claim 1, characterized in that the styrene-based thermoplastic elastomer contains one or more of the following: styrene-ethylene / butylene-styrene (SEBS) copolymer, styrene-ethylene-butylene (SEB) copolymer, styrene-butadiene-styrene (SBS), and styrene-isoprene-styrene (SIS).

5. The polypropylene resin composition according to claim 1, characterized in that the styrene-based thermoplastic elastic material has a weight-average molecular weight of about 50,000 g / mol to about 120,000 g / mol.

6. The zinc oxide may have an average particle size of about 0.7 μm to about 1.5 μm, and a specific surface area BET of about 1 m². ２ / g to approx. 7m ２ The polypropylene resin composition according to claim 1, characterized in that it is / g.

7. The polypropylene resin composition according to claim 1, characterized in that the silver-based compound contains one or more of metallic silver, silver oxide, silver halide, and a carrier containing silver ions.

8. The polypropylene resin composition according to claim 1, further comprising a polyethylene resin.

9. The polypropylene resin composition according to claim 1, characterized in that, based on the antimicrobial evaluation method of JIS Z 2801-1, a test piece measuring 5 cm x 5 cm is inoculated with Staphylococcus aureus and Escherichia coli, and after being cultured for 24 hours at 35°C and RH 90%, the measured antimicrobial activity value is approximately 2 to approximately 7, for each case.

10. The polypropylene resin composition according to claim 1, characterized in that, based on the ISO 846:2019-A evaluation method, mold spores are inoculated into an injection-molded test piece measuring 5 cm x 5 cm, and after incubation for 28 days at 29°C and 95% RH, the measured antifungal grade is 0 to 2.

11. The polypropylene resin composition according to claim 1, characterized in that, based on the ISO 21702:2019 evaluation method, an antiviral activity value of about 2 to about 7 is measured after dropping influenza A virus (H3N2): ATCC VR-1679 virus solution onto a 5 cm x 5 cm test piece and exposing it to the virus for 24 hours under conditions of 25°C and 50% RH.

12. The aforementioned polypropylene resin composition, measured according to ISO 180, exhibits a notched Izod impact strength of approximately 4 kJ / m² for a 4 mm thick test specimen. ２ ~12kJ / m ２ The polypropylene resin composition according to claim 1, characterized in that it is the same as the one described in claim 1.

13. The polypropylene resin composition according to claim 1, characterized in that, according to ISO 527, the tensile strength of a 4 mm thick test specimen measured at a rate of 50 mm / min is about 20 MPa to about 30 MPa, according to ISO 178, the flexural strength of a 4 mm thick test specimen measured at a rate of 2 mm / min is about 30 MPa to about 42 MPa, and according to ISO 178, the flexural modulus of a 4 mm thick test specimen measured at a rate of 2 mm / min is about 1,800 MPa to about 2,700 MPa.

14. The polypropylene resin composition according to claim 1, characterized in that the heat distortion temperature (HDT) of a 4 mm thick test specimen, measured under conditions of 0.45 MPa and a heating rate of 120 °C / hr in accordance with ISO 75, is approximately 106 °C to approximately 120 °C.

15. A molded article characterized by being formed from a polypropylene resin composition according to any one of claims 1 to 14.

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