Propylene resin compositions, pellets, molded articles, automotive interior and exterior materials

Abstract

To provide a propylene-based resin composition that exhibits excellent impact strength and fluidity in the resulting molded articles. [Solution] A propylene resin composition, pellets, molded articles, and automotive interior and exterior materials containing 36 to 94 parts by mass of a propylene polymer (A) that satisfies requirement (Aa) and requirement (Ab), 5 to 40 parts by mass of an ethylene-1-octene copolymer (B) that satisfies all of requirements (Ba) to (Be), and 1 to 24 parts by mass of an inorganic substance (C) (provided that the total of (A), (B), and (C) above is 100 parts by mass). Details of requirements (Aa), (Ab), and requirements (Ba) to (Be) are given in the specification.

Description

Technical Field

[0001] The present invention relates to a propylene-based resin composition, pellets, a molded article, an interior material and an exterior material for automobiles.

Background Art

[0002] Polypropylene resins are utilized in a wide range of fields such as automotive parts, machine parts, and electrical parts by taking advantage of their excellent physical properties. In order to meet the physical properties required for each application, formulations such as changing the molecular structure of the resin or blending various additives are employed. For example, in fields that require high mechanical strength such as automotive parts, compositions are prepared by blending an elastomer such as an ethylene-1-octene copolymer and an inorganic filler with a propylene block copolymer. Automotive parts are strongly required to be lightweight in order to reduce fuel consumption, and for this reason, they are being thinned. Generally, when the thickness of a molded article of polypropylene resin is reduced, the impact resistance is significantly decreased and it tends to become brittle. This tendency can be clearly grasped by measuring the impact strength. For example, Patent Document 1 discloses a composition containing an ethylene-1-octene copolymer and describes that it has injection fluidity. For example, Patent Document 2 discloses a composition containing an ethylene-1-octene copolymer and describes that it has low impact performance.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in the conventional propylene-based resin composition containing ethylene-1-octene copolymer, it has been difficult to achieve further weight reduction and impact strength at the same time. One problem to be solved by an embodiment of the present invention is to provide a propylene-based resin composition excellent in impact strength and fluidity of the obtained molded body, and pellets containing the composition. Another problem to be solved by an embodiment of the present invention is to provide an interior and exterior material for automobiles excellent in impact strength.

Means for Solving the Problems

[0005] The means for solving the above problems include the following aspects. <1> 36 to 94 parts by mass of a propylene-based polymer (A) satisfying the following requirements (A-a) and (A-b), 5 to 40 parts by mass of an ethylene-1-octene copolymer (B) satisfying all of the following requirements (B-a) to (B-e), 1 to 24 parts by mass of an inorganic substance (C), (However, the total of the propylene-based polymer (A), ethylene-1-octene copolymer (B) and inorganic substance (C) is 100 parts by mass), Propylene-based resin composition; Requirement (A-a): The melt flow rate (MFR) measured under the conditions of 230°C and 2.16 kg load in accordance with ASTM D 1238 is 70 to 120 g / 10 min; Requirement (A-b): The intrinsic viscosity ([η]) measured in decalin at 135°C of the decane-soluble part of the propylene-based polymer (A) is 0.1 to 10.0 dl / g; Requirement (B-a): It consists of 60 to 99 mol% of a structural unit (i) derived from ethylene and 1 to 40 mol% of a structural unit (ii) derived from 1-octene [where the total of the structural unit (i) and the structural unit (ii) is 100 mol%]; Requirement (B-b): The density is 850 to 870 kg / m 3 is; Requirement (Bc): Melt flow rate (MFR) measured under conditions of 190°C and 2.16 kg load, in accordance with ASTM D 1238. 2.16 The amount is 2-20g / 10 minutes; Requirement (Bd): Melt flow rate (MFR) measured under conditions of 190°C and 2.16 kg load, in accordance with ASTM D 1238. 2.16 The melt flow rate (MFR) was measured under conditions of 190°C and 10kg load in accordance with ASTM D1238. 10 ) ratio (MFR 10 / MFR 2.16 ) is between 6.0 and 8.0; Requirement (Be): The amount of elution at a temperature 20°C lower than the peak temperature observed by crystallization elution fractional chromatography is less than 23% by mass of the total mass of ethylene·1-octene copolymer (B). <2> The decane-soluble portion of the propylene polymer (A) at room temperature (23°C) is 5% to 30% by mass relative to the total mass of the propylene polymer (A). <1> The propylene resin composition described above. <3> <1> or <2> A pellet containing the propylene resin composition described above. <4> <1> or <2> A molded article comprising the propylene-based resin composition described above. <5> <1> or <2> Automotive interior and exterior materials comprising the propylene resin composition described above. [Effects of the Invention]

[0006] According to one embodiment of the present invention, a propylene-based resin composition and pellets containing the composition are provided, which have excellent impact resistance and fluidity in the resulting molded article. Furthermore, according to one embodiment of the present invention, automotive interior and exterior materials with excellent impact resistance are provided. [Modes for carrying out the invention]

[0007] The contents of the present invention will be described in detail below. The description of the constituent elements described below may be based on representative embodiments of the present invention, but the present invention is not limited to such embodiments. In this specification, the "~" symbol indicating a numerical range is used to mean that the numbers before and after it are included as the lower and upper limits, respectively. In this specification, the "~" symbol indicating a numerical range means that the units listed before or after it refer to the same unit unless otherwise specified. In this specification, a combination of two or more preferred embodiments is a more preferred embodiment. Furthermore, unless otherwise specified, each component in a composition or each structural unit in a polymer may be included alone or in combination of two or more types. In this specification, the amount of each component in a composition, or each constituent unit in a polymer, means the total amount of the multiple substances or constituent units present in the composition, unless otherwise specified, if there are multiple substances or constituent units corresponding to each component or constituent unit in the composition. The present invention will be described in detail below.

[0008] (Propylene resin composition) The propylene-based resin composition according to the present invention comprises 36 to 94 parts by mass of a propylene-based polymer (A) that satisfies the following requirements (Aa) and (Ab), 5 to 40 parts by mass of ethylene-1-octene copolymer (B) that satisfies all of the following requirements (Ba) to (Be), Inorganic substance (C) 1-24 parts by mass (However, the total amount of the above-mentioned propylene polymer (A), ethylene-1-octene copolymer (B), and inorganic substance (C) shall be 100 parts by mass.) Requirement (Aa): The melt flow rate (MFR) measured under conditions of 230°C and a 2.16 kg load, in accordance with ASTM D 1238, is 70-120 g / 10 min; Requirement (A-b): The intrinsic viscosity ([η]) of the decane-soluble portion of the propylene-based polymer (A) measured in decalin at 135°C is 0.1 to 10.0 dl / g; Requirement (B-a): It consists of 60 to 99 mol% of the structural unit (i) derived from ethylene and 1 to 40 mol% of the structural unit (ii) derived from 1-octene [provided that the total of the structural unit (i) and the structural unit (ii) is 100 mol%]; Requirement (B-b): The density is 850 to 870 kg / m 3 ; Requirement (B-c): The melt flow rate (MFR 2.16 ) measured under the conditions of 190°C and 2.16 kg load in accordance with ASTM D 1238 is 2 to 20 g / 10 min; Requirement (B-d): The ratio (MFR 2.16 ) of the melt flow rate (MFR 10 ) measured under the conditions of 190°C and 10 kg load in accordance with ASTM D 1238 to the melt flow rate (MFR 10 / MFR 2.16 ) measured under the conditions of 190°C and 2.16 kg load in accordance with ASTM D 1238 is 6.0 to 8.0; Requirement (B-e): The elution amount at a temperature 20°C lower than the peak temperature observed by crystallization elution fractionation chromatography is less than 23% by mass with respect to the total mass of the ethylene·1-octene copolymer (B).

[0009] The propylene-based resin composition according to the present invention has the above configuration, and thus has excellent fluidity and excellent impact strength of the obtained molded body.<​​The propylene-based resin composition according to the present invention contains 36 to 94 parts by mass of a propylene-based polymer (A) that satisfies requirements (Aa) and (Ab), and 5 to 40 parts by mass of an ethylene-1-octene copolymer (B) that satisfies all requirements (Ba) to (Be). In particular, since it contains specific amounts of a propylene-based polymer (A) that satisfies specific MFRs, etc., and an ethylene-1-octene copolymer (B) that satisfies specific MFRs, etc., the ethylene-1-octene copolymer (B) is more easily dispersed in the propylene-based polymer (A) within the propylene-based resin composition. As a result, it is estimated that the fluidity of the composition is improved, and impact resistance is exhibited in the resulting molded article. The components of the propylene-based resin composition will be described in detail below.

[0010] <Propylene-based polymer (A)> The propylene polymer (A) is not particularly limited and may be a propylene homopolymer or a copolymer of propylene and an α-olefin other than propylene (hereinafter also referred to as "other α-olefin"). The copolymer may be a block copolymer or a random copolymer. From the viewpoint of having excellent fluidity and excellent impact strength of the resulting molded article, the propylene-based polymer (A) is preferably a copolymer of propylene and another α-olefin. A propylene polymer (A) is a propylene polymer whose main component is propylene. In a propylene polymer (A), the content of constituent units derived from propylene is preferably 50 mol% or more, more preferably 80 mol% or more, and even more preferably 90 mol% or more, relative to the total number of moles of all constituent units that make up the propylene polymer.

[0011] Other α-olefins mentioned above include, for example, ethylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-octene, 1-decene, 1-dodecene, 1-tetradodecene, 1-hexadodecene, 1-octadodecene, 1-eicosene, 4-methyl-1-pentene, 2-methyl-1-butene, 3-methyl-1-butene, 3-methyl-1-butene, 3,3-dimethyl-1-butene, diethyl-1-butene, trimethyl-1-butene, 3-methyl Examples include ethylene and α-olefins having 4 to 20 carbon atoms, such as 1-pentene, ethyl-1-pentene, propyl-1-pentene, dimethyl-1-pentene, methylethyl-1-pentene, diethyl-1-hexene, trimethyl-1-pentene, 3-methyl-1-hexene, dimethyl-1-hexene, 3,5,5-trimethyl-1-hexene, methylethyl-1-heptene, trimethyl-1-heptene, ethyl-1-octene, and methyl-1-nonene. Among these, other preferred α-olefins are ethylene and α-olefins having 4 to 8 carbon atoms, with ethylene, 1-hexene, and 1-octene being more preferred.

[0012] Suitable specific examples of copolymers of propylene with other α-olefins include propylene-ethylene copolymer, propylene-1-butene copolymer, propylene-1-pentene copolymer, propylene-1-hexene copolymer, propylene-1-octene copolymer, and propylene-ethylene-1-butene copolymer. Among these, propylene-ethylene copolymer is preferred as the copolymer of propylene and other α-olefins.

[0013] The propylene polymer (A) may contain biomass-derived monomers (α-olefins with 2 to 20 carbon atoms). The monomers constituting polymer (A) may consist solely of biomass-derived monomers, or they may contain both biomass-derived monomers and fossil fuel-derived monomers. Biomass-derived monomers are monomers made from any renewable natural raw materials and their residues, including fungi, yeasts, algae, and bacteria, which are plant-derived or animal-derived, and which contain carbon 14 10 C isotopes -12 It contains a certain proportion, and the biomass carbon concentration (pMC) measured according to ASTM D 6866 is approximately 100 pMC. Biomass-derived monomers are obtained by conventionally known methods. It is preferable from the viewpoint of reducing environmental impact (mainly greenhouse gas reduction) that the propylene polymer (A) according to the present invention contains biomass-derived monomers. If the polymer production conditions such as polymerization catalyst and polymerization process polymerization temperature are the same, even if the raw material monomer contains biomass-derived monomers, 14 10 C isotopes -12 ~10 -14 Aside from the small proportions it contains, its molecular structure is equivalent to that of propylene polymers made from fossil fuel-derived monomers. Therefore, its performance is considered to be the same.

[0014] The propylene polymer (A) may contain monomers derived from chemical recycling (α-olefins with 2 to 20 carbon atoms). The monomers constituting polymer (A) may consist solely of monomers derived from chemical recycling, or they may contain monomers derived from chemical recycling, monomers derived from fossil fuels, and / or monomers derived from biomass. The monomers derived from chemical recycling are obtained by conventionally known methods. It is preferable for the propylene polymer (A) according to the present invention to contain monomers derived from chemical recycling from the viewpoint of reducing environmental impact (mainly waste reduction). Even if the raw material monomers contain monomers derived from chemical recycling, since monomers derived from chemical recycling are monomers obtained by depolymerizing polymers such as waste plastics back to monomer units such as ethylene by depolymerization, thermal decomposition, etc., and monomers produced using such monomers as raw materials, if the polymer production conditions such as polymerization catalyst, polymerization process, and polymerization temperature are the same, the molecular structure is equivalent to that of a propylene polymer consisting of monomers derived from fossil fuels. Therefore, the performance is also considered to be the same.

[0015] From the viewpoint of having excellent fluidity and excellent impact strength of the resulting molded article, the propylene polymer (A) is preferably at least one polymer selected from the group consisting of propylene block copolymers and propylene random copolymers, and more preferably at least one polymer selected from the group consisting of propylene-ethylene block copolymers and propylene-ethylene random copolymers.

[0016] <<Requirement (Aa)>> The propylene polymer (A) has a melt flow rate (MFR) of 70-120 g / 10 min, measured under conditions of 230°C and a 2.16 kg load, in accordance with ASTM D1238. When the MFR of the propylene polymer (A) is within the above range, it exhibits excellent fluidity, resulting in excellent moldability for the resulting automotive interior and exterior materials. From the above viewpoint, the MFR of the propylene polymer (A) is preferably 75 to 120 g / 10 min, more preferably 80 to 120 g / 10 min, and even more preferably 85 to 120 g / 10 min.

[0017] It is preferable that the decane-soluble portion of the propylene polymer (A) at room temperature (23°C) is 5% to 30% by mass relative to the total mass of the propylene polymer (A). The decane-soluble portion at room temperature (23°C) (hereinafter sometimes referred to as the "room temperature (23°C) decane-soluble portion") refers to the component soluble in n-decane at 23°C (hereinafter also referred to as the "decane-soluble portion") when propylene polymer (A) is separated with n-decane solvent. The decane-insoluble portion at room temperature (23°C) refers to the component insoluble in n-decane at 23°C (hereinafter also referred to as the "decane-insoluble portion") when propylene copolymer (A) is separated with n-decane solvent. The soluble and insoluble portions of decane are measured by the method used in the examples described later. The decane-soluble portion is preferably 5 to 30% by mass, more preferably 7 to 25% by mass, and even more preferably 10 to 20% by mass, relative to the total mass of the propylene polymer (A), and the decane-insoluble portion is preferably 70 to 95% by mass, more preferably 75 to 93% by mass, and even more preferably 80 to 90% by mass. When the content of decane-soluble and decane-insoluble portions is within the above range, the automotive interior and exterior materials formed from the composition exhibit excellent mechanical properties such as rigidity and impact resistance.

[0018] The decane-soluble portion, when the copolymer is mainly a propylene-based polymer (A), preferably consists of a propylene-ethylene random copolymer, and may include a portion of the propylene homopolymer, such as by-products generated during polymerization, such as low molecular weight substances. When the propylene polymer (A) is a copolymer of the above-mentioned propylene and another α-olefin, the other α-olefin contained in the decane-soluble portion may be ethylene and / or α-olefins having 4 to 12 carbon atoms. Specific examples of such other α-olefins include ethylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 3-methyl-1-pentene, 1-heptene, 1-octene, 1-nonene, 1-decene, and 1-dodecene. Among these, ethylene is preferred as the other α-olefin.

[0019] The decane-insoluble portion usually consists only of structural units derived from propylene; however, if the propylene polymer (A) is a copolymer of the above-mentioned propylene and another α-olefin, it may contain a small amount, for example, 10 mol% or less, preferably 5 mol% or less, of structural units derived from other monomers other than propylene. Other monomers besides propylene include, for example, α-olefins other than propylene such as ethylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 3-methyl-1-pentene, 1-heptene, 1-octene, 1-nonene, 1-decene, and 1-dodecene; vinyl compounds such as styrene, vinylcyclopentene, vinylcyclohexane, and vinylnorbornane; vinyl esters such as vinyl acetate; unsaturated organic acids or their derivatives such as maleic anhydride; conjugated dienes; and unconjugated polyenes such as dicyclopentadiene, 1,4-hexadiene, dicyclooctadiene, methylenenorbornene, and 5-ethylidene-2-norbornene. Among these, ethylene and α-olefins having 4 to 10 carbon atoms are preferred. These may be copolymerized individually or two or more together.

[0020] <<Requirements(Ab)>> The intrinsic viscosity ([η]) of the decane-soluble portion of the propylene polymer (A), measured in decalin at 135°C, is 0.1 to 10.0 dl / g, preferably 1.0 to 9.8 dl / g, more preferably 1.5 to 9.5 dl / g, and even more preferably 2.0 to 9.0 dl / g. When the intrinsic viscosity ([η]) of the decane-soluble portion is within the above range, the automotive interior and exterior materials formed from the composition exhibit an excellent balance between rigidity and impact resistance. If further mechanical properties are required for the automotive interior and exterior materials formed from the composition, the intrinsic viscosity ([η]) of the decane-soluble portion is preferably 4.0 to 9.0 dl / g, more preferably 4.5 to 8.7 dl / g, and even more preferably 5.0 to 8.4 dl / g.

[0021] The content of the propylene polymer (A) is 36 to 94 parts by mass per 100 parts by mass of the total of the propylene polymer (A), the ethylene-1-octene copolymer (B) described later, and the inorganic substance (C). From the viewpoint of having excellent impact strength and fluidity in the resulting molded article, the content of the propylene polymer (A) is preferably 45 to 90 parts by mass, more preferably 53 to 85 parts by mass, and even more preferably 61 to 77 parts by mass (provided that the total of the propylene polymer (A), the ethylene-1-octene copolymer (B) described later, and the inorganic substance (C) is 100 parts by mass). The propylene polymer (A) may be a single type or may contain two or more types.

[0022] The method for producing the propylene polymer (A) is not particularly limited and can be produced by conventionally known methods, for example, by referring to the method described in paragraphs

[0018] to

[0026] of Japanese Patent Application Publication No. 2004-323545.

[0023] <Ethylene-1-octene copolymer (B)> <<Requirements (Ba)>> Ethylene-1-octene copolymer (B) consists of 60-99 mol% of constituent units (i) derived from ethylene and 1-40 mol% of constituent units (ii) derived from 1-octene (provided that the sum of constituent units (i) and (ii) is 100 mol%). When the content of constituent units (i) and (ii) of the ethylene-1-octene copolymer is within the above range, the automotive interior and exterior materials formed from the composition exhibit an excellent balance between mechanical strength and impact resistance. From the above viewpoint, the lower limit of the content range of the constituent unit (i) derived from ethylene is preferably 70 mol%, more preferably 75 mol%, and even more preferably 80 mol%. The upper limit of the content range of the constituent unit (i) derived from ethylene is preferably 97 mol%, more preferably 94 mol%, and even more preferably 90 mol%. From the above viewpoint, the lower limit of the content range of the constituent unit (ii) derived from 1-octene is preferably 3 mol%, more preferably 6 mol%, and even more preferably 10 mol%. The upper limit of the content range of the constituent unit (ii) derived from 1-octene is preferably 30 mol%, more preferably 25 mol%, and even more preferably 20 mol%.

[0024] The monomers (ethylene and 1-octene) constituting the ethylene-1-octene copolymer (B) may be fossil fuel-derived monomers, biomass-derived monomers, or may contain both biomass-derived monomers and fossil fuel-derived monomers. Biomass-derived monomers are synonymous with biomass-derived monomers in the propylene-based polymer (A) described above. Furthermore, the monomers constituting the ethylene-1-octene copolymer (B) may consist solely of chemically recycled monomers, or they may include chemically recycled monomers, fossil fuel-derived monomers, and / or biomass-derived monomers. Chemically recycled monomers are synonymous with chemically recycled monomers in the propylene-based polymer (A) described above.

[0025] <<Requirements (Bb)>> Ethylene-1-octene copolymer (B) has a density of 850-870 kg / m³. 3 That is the case. Ethylene-1-octene copolymer (B) having a density within the above range results in molded articles that are lightweight and have an excellent balance of mechanical strength and impact resistance. From the above viewpoint, the lower limit of the above density range is preferably 852 kg / m³. 3 , more preferably 854 kg / m 3 More preferably 855 kg / m 3 The upper limit of the density range is preferably 868 kg / m³. 3 minutes, more preferably 864 kg / m³ 3 More preferably 863 kg / m 3 That is the case. The density is measured by the method used in the examples described later.

[0026] <<Requirements (Bc)>> Ethylene-1-octene copolymer (B) has a melt flow rate (MFR) in the range of 2 to 20 g / 10 min at 190°C and a 2.16 kg load, in accordance with ASTM D1238. When the MFR of the ethylene-1-octene copolymer is within the above range, the automotive interior and exterior materials formed from the composition exhibit excellent moldability and impact resistance. From the above viewpoint, the lower limit of the MFR of the ethylene-1-octene copolymer is preferably 2.5 g / 10 min, more preferably 3.0 g / 10 min, and even more preferably 3.5 g / 10 min. The upper limit of the MFR of the ethylene-1-octene copolymer is preferably 15.0 g / 10 min, more preferably 10.0 g / 10 min, and even more preferably 8.0 g / 10 min.

[0027] <<Requirements (Bd)>> Ethylene-1-octene copolymer (B) has a melt flow rate (MFR) measured under conditions of 190°C and a 2.16 kg load, in accordance with ASTM D 1238. 2.16 The melt flow rate (MFR) was measured under conditions of 190°C and 10kg load in accordance with ASTM D1238.10 ) ratio (MFR 10 / MFR 2.16 ) is between 6.0 and 8.0. Ethylene-1-octene copolymer (B) (MFR 10 / MFR 2.16 When the above range is present, the automotive interior and exterior materials formed from the composition have an excellent balance of impact resistance and moldability. From the above perspective, (MFR 10 / MFR 2.16 The lower limit of (MFR) is preferably 6.3, more preferably 6.6, and even more preferably 6.7. 10 / MFR 2.16 The upper limit of the range is preferably 7.8, more preferably 7.6, and even more preferably 7.4.

[0028] <<Requirements (Be)>> The elution amount of ethylene-1-octene copolymer (B) at a temperature 20°C lower than the peak temperature observed by crystallization elution fractional chromatography (CEF) is less than 23% by mass of the total mass of ethylene-1-octene copolymer (B), preferably 20% by mass or less, and more preferably 18% by mass or less. A elution rate of less than 23% by mass at a temperature 20°C below the peak temperature observed by crystallization-elution fractional chromatography (CEF) is preferable because it results in fewer components eluting at low temperatures and superior mechanical properties. The lower the elution rate at 20°C below the peak temperature, the greater the aforementioned effect, so there is no particular lower limit, but the range of elution rates that can usually be obtained is 0.1% by mass or higher. Furthermore, since a lower elution rate at low temperatures results in superior mechanical properties even at equivalent densities, we focused on the 20°C range below the peak temperature. The "peak temperature" mentioned above refers to the temperature at which the amount of elution is highest in the compositional distribution observed in crystallization elution fractional chromatography (CEF). The amount of elution at the peak temperature is preferably 20% by mass or less, more preferably 15% by mass or less, and even more preferably 11% by mass or less, based on the total mass of the ethylene-1-octene copolymer (B). Ethylene-1-octene copolymer (B) with the above elution amount within the above range has fewer low-crystalline components, is less sticky, and the resulting molded article has excellent mechanical properties. The methods for measuring the peak temperature and elution amount of the compositional distribution obtained by crystallization-elution fractional chromatography (CEF) will be described in detail in the examples below.

[0029] The ethylene-1-octene copolymer (B) has a ratio of weight-average molecular weight (Mw) to number-average molecular weight (Mn) in polypropylene terms, determined by gel permeation chromatography (GPC) (Mw / Mn: molecular weight distribution), which is usually 4.0 or less, preferably 3.5 or less, more preferably 3.0 or less, even more preferably 2.8 or less, and particularly preferably 2.5 or less. Ethylene-1-octene copolymer (B) with a molecular weight distribution within the above range exhibits a well-balanced and excellent combination of mechanical strength, impact resistance, and low stickiness in the resulting molded articles.

[0030] The lower limit of the melting point (Tm) of ethylene-1-octene copolymer (B), as measured by differential scanning calorimetry (DSC), is usually 15°C or higher, preferably 19°C or higher, more preferably 22°C or higher, even more preferably 25°C or higher, and particularly preferably 28°C or higher. The upper limit of the melting point (Tm) is usually 80°C or lower, preferably 60°C or lower, more preferably 55°C or lower, even more preferably 50°C or lower, and particularly preferably 48°C or lower. When the melting point (Tm) falls within the above upper and lower limits, the resulting molded body, which contains an appropriate amount of crystalline components, exhibits an excellent balance between blocking resistance and impact resistance. The differential scanning calorimetry (DSC) measurement conditions will be described in detail in the examples below.

[0031] The content of ethylene-1-octene copolymer (B) is 5 to 40 parts by mass per 100 parts by mass of the total of the propylene polymer (A), ethylene-1-octene copolymer (B), and inorganic substance (C) described later. From the viewpoint of having excellent impact strength and excellent fluidity of the composition, the content of ethylene-1-octene copolymer (B) is preferably 7 to 35 parts by mass, more preferably 10 to 30 parts by mass, and even more preferably 15 to 25 parts by mass (where the total of the propylene polymer (A), ethylene-1-octene copolymer (B) described later, and inorganic substance (C) is 100 parts by mass).

[0032] There are no particular restrictions on the method of producing ethylene-1-octene copolymer (B), but it can be suitably produced using a metallocene catalyst.

[0033] <Inorganic substances (C)> The propylene-based resin composition according to the present invention contains an inorganic substance (C). The inorganic substance (C) is not particularly limited as long as it is an inorganic compound; any known inorganic compound can be used. Examples of inorganic materials (C) include carbon black or carbon black surface-treated with graphite or silane coupling agents, fine silica, silica (including fuzzy silica, precipitated silica, diatomaceous earth and quartz, etc.), alumina, iron oxide, magnesium oxide, titanium oxide, antimony trioxide, zirconium oxide, barium oxide and calcium oxide, etc.; hydroxide fillers including aluminum hydroxide and magnesium hydroxide, etc.; silicate fillers including aluminum silicate (clay), magnesium silicate (talc), mica, kaolin, calcium silicate, glass fiber, glass flakes and glass beads, etc.; sedimentary rock fillers including diatomaceous earth and limestone, etc., montmorillonite (mo Clay mineral fillers including montmorillonite, magnesian montmorillonite, tetmontmorillonite, tetmagnesianmontmorillonite, beiderite, aluminumian beiderite, nonthoronite, aluminumiannonthoronite, saponite, aluminumiansaponite, hectorite, souconite, stevensite, and bentonite; magnetic fillers including ferrite, iron, and cobalt; conductive fillers including silver, gold, copper, and alloys thereof; calcium carbonate, basic magnesium carbonate, dolomite, magnesium sulfate, aluminum sulfate, barium sulfate, barium titanate, potassium titanate, calcium sulfate, calcium sulfite, silicon carbide, and boron nitride.

[0034] As inorganic material (C), silica, magnesium sulfate, barium sulfate, calcium carbonate, magnesium hydroxide, magnesium oxide, and talc are preferred, magnesium sulfate, barium sulfate, calcium carbonate, and talc are more preferred, and from the viewpoint of balancing price, performance, handling, and supply stability, barium sulfate, calcium carbonate, and talc are even more preferred, and talc is particularly preferred. These inorganic substances (C) may be present individually or in combination of two or more.

[0035] From the viewpoint of processability, the particle size (average particle diameter) of the inorganic substance (C) is preferably 0.01 μm to 100 μm, more preferably 0.01 μm to 80 μm, and even more preferably 0.01 μm to 50 μm. The particle size (average particle diameter) of the above inorganic material is the 50% particle diameter (d50) obtained from the integrated percentage distribution curve measured using a laser diffraction particle size distribution analyzer.

[0036] The content of inorganic substance (C) is 1 to 24 parts by mass per 100 parts by mass of the total of the propylene polymer (A), ethylene-1-octene copolymer (B), and inorganic substance (C). From the viewpoint of having excellent impact strength and fluidity in the resulting molded article, the content of inorganic substance (C) is preferably 5 to 17 parts by mass, and more preferably 8 to 14 parts by mass (provided that the total of the propylene polymer (A), the ethylene-1-octene copolymer (B) described later, and inorganic substance (C) is 100 parts by mass).

[0037] <Content of ingredients (A) to (C)> In the propylene-based resin composition according to the present invention, the respective contents of the propylene polymer (A), ethylene-1-octene copolymer (B), and inorganic substance (C) are as follows, based on 100% by mass of the total contents of components (A) to (C): propylene polymer (A) 36-94% by mass, ethylene-1-octene copolymer (B) 5-40% by mass, and inorganic substance (C) 1-24% by mass, preferably propylene polymer (A) 45-90% by mass. The mixture consists of 7-35% by mass of ethylene-1-octene copolymer (B) and 3-20% by mass of inorganic material (C), more preferably 53-85% by mass of propylene polymer (A), 10-30% by mass of ethylene-1-octene copolymer (B) and 5-17% by mass of inorganic material (C), particularly preferably 61-77% by mass of propylene polymer (A), 15-25% by mass of ethylene-1-octene copolymer (B) and 8-14% by mass of inorganic material (C). The propylene-based resin composition according to the present invention has high impact strength even when lightened, provided that the content of components (A) to (C) is within the above range.

[0038] <Other ingredients> The propylene-based resin composition according to the present invention may further contain, if necessary, other polymers other than the propylene-based polymer (A) and ethylene-1-octene copolymer (B), and additives other than inorganic substances (C). Other polymers include, for example, homopolypropylene, copolymers of propylene with α-olefins having 2 to 20 carbon atoms other than propylene, etc. The copolymer may be a random copolymer or a block copolymer. The content of the above-mentioned other polymers is preferably 10% by mass or less, more preferably 5% by mass or less, and even more preferably 1% by mass or less, based on the total mass of the propylene resin composition.

[0039] Examples of additives include, but are not limited to, weather stabilizers, heat stabilizers, UV absorbers, infrared absorbers, antistatic agents, anti-slip agents, anti-blocking agents, anti-fogging agents, lubricants, pigments, dyes, plasticizers, anti-aging agents, hydrochloric acid absorbers, antioxidants, nucleating agents, antifungal agents, antibacterial agents, flame retardants, organic fillers, and softeners. These additives may be included individually or in combination.

[0040] Examples of softening agents include petroleum-based substances such as process oil, lubricating oil, paraffin, liquid paraffin, polyethylene wax, polypropylene wax, petroleum asphalt, and petrolatum; coal tars such as coal tar and coal tar pitch; fatty oils such as castor oil, linseed oil, rapeseed oil, soybean oil, and coconut oil; waxes such as tall oil, beeswax, carnauba wax, and lanolin; fatty acids or their metal salts such as ricinoleic acid, palmitic acid, 12-hydroxystearic acid stearate, montanic acid, oleic acid, and erucic acid; synthetic polymer compounds such as petroleum resin, coumarone indene resin, and atactic polypropylene; ester-based plasticizers such as dioctyl phthalate, dioctyl adipate, and dioctyl sebacate; microcrystalline wax, liquid polybutadiene or its modified or hydrogenated products; and liquid thiocol.

[0041] Examples of softening agents include aromatic carboxylic acid esters (such as dibutyl phthalate), aliphatic carboxylic acid esters (such as methylacetyl ricinolate), aliphatic dialbonate esters (such as adipic acid-propylene glycol polyesters), aliphatic tricarboxylic acid esters (such as triethyl citrate), phosphate triesters (such as triphenyl phosphate), epoxy fatty acid esters (such as epoxybutyl stearate), and petroleum resins.

[0042] Examples of mold release agents include lower (C1-C4) alcohol esters of higher fatty acids (such as butyl stearate), polyhydric alcohol esters of fatty acids (C4-C30) (such as hydrogenated castor oil), glycol esters of fatty acids, and liquid paraffin.

[0043] Examples of antioxidants include phenolic antioxidants (such as 2,6-di-t-butyl-4-methylphenol), polycyclic phenolic antioxidants (such as 2,2'-methylenebis(4-methyl-6-t-butylphenol)), phosphorus-based antioxidants (such as tetrakis(2,4-di-t-butylphenyl)-4,4-biphenylenediphosphonate), and amine-based antioxidants (such as N,N-diisopropyl-p-phenylenediamine).

[0044] Examples of flame retardants include phosphate esters and other phosphorus compounds such as ammonium polyphosphate, ethylenebistris(2-cyanoethyl)phosphonium chloride, tris(tribromophenyl)phosphate, tris(tribromophenyl)phosphate, and tris(3-hydroxypropyl)phosphine oxide; chlorinated flame retardants such as chlorinated paraffin, chlorinated polyolefin, and perchlorocyclopentadecane; brominated flame retardants such as hexabromobenzene, ethylenebisdibromonolbornanedicarboxyimide, ethylenebistetrabromophthalimide, tetrabromobisphenol A derivatives, tetrabromobisphenol S, and tetrabromodipentaerythritol; and mixtures thereof.

[0045] Examples of UV absorbers include benzotriazole-based, benzophenone-based, salicylic acid-based, and acrylate-based types.

[0046] Examples of antibacterial agents include quaternary ammonium salts, pyridine compounds, organic acids, organic acid esters, halogenated phenols, and organic iodines.

[0047] Examples of surfactants include nonionic, anionic, cationic, or amphoteric surfactants. Examples of nonionic surfactants include polyethylene glycol-type nonionic surfactants such as higher alcohol ethylene oxide adducts, fatty acid ethylene oxide adducts, higher alkylamine ethylene oxide adducts, and polypropylene glycol ethylene oxide adducts; and polyhydric alcohol-type nonionic surfactants such as fatty acid esters of polyethylene oxide and glycerin, fatty acid esters of pentaerythritol, fatty acid esters of sorbitol or sorbitan, alkyl ethers of polyhydric alcohols, and aliphatic amides of alkanolamines. Examples of anionic surfactants include sulfate esters of alkali metal salts of higher fatty acids, sulfonates such as alkylbenzene sulfonates, alkyl sulfonates, and paraffin sulfonates, and phosphate esters such as higher alcohol phosphate esters. Cationic surfactants include quaternary ammonium salts such as alkyltrimethylammonium salts. Amphoteric surfactants include amino acid-type amphoteric surfactants such as higher alkylaminopropionates, and betaine-type amphoteric surfactants such as higher alkyldimethylbetaine and higher alkylhydroxyethylbetaine.

[0048] Examples of antistatic agents include the surfactants mentioned above, fatty acid esters, and polymeric antistatic agents. Examples of fatty acid esters include esters of stearic acid and oleic acid, and examples of polymeric antistatic agents include polyether ester amides.

[0049] Examples of pigments include inorganic pigments (titanium dioxide, iron oxide, chromium oxide, cadmium sulfide, etc.) and organic pigments (azo lakes, thioindigos, phthalocyanines, anthraquinones). Examples of dyes include azo dyes, anthraquinone dyes, triphenylmethane dyes, etc.

[0050] Examples of slip agents include waxes (such as carnauba wax), higher fatty acids (such as stearic acid), higher fatty acid salts (such as calcium stearate), higher alcohols (such as stearyl alcohol), and higher fatty acid amides (such as stearic acid amide and erucic acid amide).

[0051] <Method for producing propylene resin compositions> The method for producing the propylene-based resin composition according to the present invention is not particularly limited, and conventionally known production methods can be used, for example. Preferably, the method for producing the propylene-based resin composition involves melt-kneading the above-mentioned components (A) to (C) to produce the composition. The melt-kneading method is not particularly limited, and a method can be employed in which commonly used known mixers such as kneaders, roll mills, Banbury mixers, single-screw or twin-screw extruders are used to melt-knead at, for example, 180 to 250°C, followed by granulation or pulverization. This method can yield high-quality propylene-based resin composition pellets in which each component (A) to (C) and any additives used as needed are uniformly dispersed and mixed.

[0052] <Pellets> The pellets according to the present invention contain the above-mentioned propylene-based resin composition. The pellets may further contain components other than the propylene-based resin composition, to the extent that they do not impair the effects of the present invention. Examples of components other than the propylene-based resin composition include natural oils, synthetic oils, surfactants, and other additives.

[0053] There are no particular restrictions on the shape of the pellets; for example, they may be granular, columnar, plate-shaped, spherical, etc. The average particle size of the pellets is not particularly limited, but from the viewpoint of facilitating smooth supply of resin to the molding machine and smooth melting of the resin, it is preferably 1 to 7 mm, more preferably 2 to 5 mm in the strand direction, and preferably 1 to 5 mm, more preferably 2 to 4 mm in the cutting direction (direction perpendicular to the strand direction).

[0054] There are no particular limitations on the method for producing pellets according to the present invention, but they can be produced by melt-kneading each component of the propylene-based resin composition, followed by a granulation or pulverization step. The method of melt-kneading each component of the polyamide resin composition in the method for producing pellets is the same as the method of melt-kneading in the method for producing the propylene-based resin composition described above.

[0055] The pellets according to the present invention can be used in the manufacture of various molded articles, and the applications of the molded articles are not particularly limited. For example, they can be used in molded articles such as interior and exterior materials for automobiles, as described later.

[0056] The propylene-based resin composition according to the present invention has high impact strength even when lightened. Taking advantage of this property, various molded articles can be manufactured from the propylene-based resin composition according to the present invention.

[0057] <Molded body> A molded article containing the above-mentioned propylene-based resin composition can be obtained by molding the propylene-based resin composition using conventionally known molding methods, such as blow molding, injection molding, press molding, extrusion molding, inflation molding, extrusion blow molding, injection blow molding, vacuum molding, calendering, and molten T-die casting. Among these molding methods, an injection-molded article formed by injection molding is preferred.

[0058] <Automotive interior and exterior materials> From the viewpoint of having high impact strength even when lightened, suitable examples of molded articles include automotive parts such as interior and exterior materials for automobiles that contain a propylene-based resin composition. The interior and exterior materials of the above-mentioned automobile are not particularly limited and include automobile parts formed by injection molding or the like. Specifically, examples of interior materials of automobiles include trim, instrument panels, and column covers, and specific examples of exterior materials of automobiles include fenders, bumpers, side moldings, mudguards, and mirror covers. [Examples]

[0059] The present invention will now be described in more detail with reference to examples, but the present invention is not limited thereto. The components used in the following examples and comparative examples are as follows:

[0060] As the propylene polymer (A), the propylene polymers (A-1) to (a-1) listed in Table 1 were used. The MFRs below were measured in accordance with ASTM D1238. The intrinsic viscosity [η] below was measured at 135°C using decalin solvent. • Propylene polymer (A-1): A block copolymer consisting of a propylene homopolymer and a propylene-ethylene random copolymer. MFR (230℃, 2.16kg load): 90g / 10min n-decane insoluble portion at 23°C: 89% by mass n-decane soluble portion at 23°C: 11% by mass Intrinsic viscosity [η] of the n-decane soluble portion at 23°C: 8.1 dl / g

[0061] • Propylene polymer (A-2): Manufactured by BRASKEM, product name: TI2900C, MFR (230℃, 2.16kg load): 115g / 10min n-decane insoluble portion at 23°C: 92% by mass n-decane soluble portion at 23°C: 8% by mass Intrinsic viscosity [η] of the n-decane-soluble portion at 23°C: 5.8 dl / g

[0062] • Propylene polymer (A-3): Manufactured by Sun Allomer, product name: VMD81M, MFR (230℃, 2.16kg load): 100g / 10min n-decane insoluble portion at 23°C: 84% by mass n-decane soluble portion at 23°C: 16% by mass Intrinsic viscosity [η] of the n-decane soluble portion at 23°C: 2.7 dl / g

[0063] • Propylene polymer (A-4): Borouge brand, product name BJ356AI, MFR (230℃, 2.16kg load): 100g / 10min n-decane insoluble portion at 23°C: 87% by mass n-decane soluble portion at 23°C: 13% by mass Intrinsic viscosity [η] of the n-decane soluble portion at 23°C: 2.4 dl / g

[0064] • Propylene polymer (a-1): A block copolymer consisting of a propylene homopolymer portion and a propylene-ethylene random copolymer portion. MFR (230℃, 2.16kg load): 57g / 10min n-decane insoluble portion at 23°C: 89% by mass n-decane soluble portion at 23°C: 11% by mass Intrinsic viscosity [η] of the n-decane-soluble portion at 23°C: 6.8 dl / g

[0065] [Table 1]

[0066] The following ethylene-1-octene copolymers (B-1) to (B-6) were used as ethylene-1-octene copolymer (B).

[0067] [Ethylene-1-octene copolymer (B-1)] As the ethylene-1-octene copolymer (B-1), an ethylene-1-octene copolymer obtained by the following manufacturing method was used. <Manufacturing Example 1: Production of Ethylene-1-Octene Copolymer (B-1)> In one of the feed ports of a 50L continuous polymerizer equipped with stirring blades, a hexane solution of triisobutylaluminum was added as a co-catalyst at a rate of 20 mmol / hr, and bis(4-methoxyphenyl)methylene(η) as the main catalyst. 5 -cyclopentadienyl)(η 5 A hexane solution of (-tetramethyloctahydrodibenzofluorenyl)hafnium dichloride was supplied at a rate of 0.0082 mmol / hr, and a hexane slurry solution of triphenylcarbenium tetrakis(pentafluorophenyl)borate was supplied at a rate of 0.034 mmol / hr. Dehydrated and purified n-hexane was continuously supplied so that the total amount of the catalyst solution and the n-hexane used as the polymerization solvent was 37.3 L / hr. Simultaneously, ethylene was continuously supplied to another supply port of the polymerizer at a rate of 6.4 kg / hr, 1-octene at 8.4 kg / hr, and hydrogen at 110 NL / hr. Continuous solution polymerization was carried out under conditions of a polymerization temperature of 130°C, a total pressure of 2.5 MPaG, and a residence time of 0.5 hours. The n-hexane / toluene mixed solution of ethylene-1-octene copolymer produced in the polymerizer was continuously discharged through an outlet provided at the bottom of the polymerizer, and the jacket portion was heated to 3 kg / cm³ so that the n-hexane / toluene mixed solution of ethylene-1-octene copolymer reached 150°C. 2 The mixture was led to a connecting pipe heated with steam. Immediately before reaching the connecting pipe, a supply port was provided for injecting methanol, a catalyst deactivator. Methanol was injected at a rate of approximately 11 L / hr to combine with the n-hexane / toluene mixed solution of ethylene-1-octene copolymer. A n-hexane / toluene mixed solution of ethylene-1-octene copolymer, kept at approximately 200°C in a steam-jacketed connecting pipe, was continuously supplied to a flash tank by adjusting the opening of a pressure control valve located at the end of the connecting pipe to maintain a pressure of approximately 2.5 MPaG. During transfer to the flash tank, the solution temperature and pressure control valve opening were set to maintain a pressure of approximately 0.05 MPaG and a steam temperature of approximately 200°C in the flash tank. Subsequently, the strands were passed through a single-screw extruder with a die temperature set to 190°C, cooled in a water tank, and cut with a pellet cutter to obtain ethylene-1-octene copolymer (B-1) as pellets. The yield was 8.1 kg / 2hr.

[0068] <Manufacturing Example 2: Ethylene-1-octene copolymer (B-2)> Ethylene-1-octene copolymer (B-2) was produced in the same manner as in Production Example 1, except that the supply amounts of 1-octene, ethylene, and polymerization temperature were adjusted as shown in Table 2.

[0069] <Manufacturing Example 3: Ethylene-1-octene copolymer (B-3)> Ethylene-1-octene copolymer (B-3) was produced in the same manner as in Production Example 1, except that the supply amounts of 1-octene and ethylene were adjusted as shown in Table 2.

[0070] <Manufacturing Example 4: Ethylene-1-octene copolymer (B-4)> Ethylene-1-octene copolymer (B-4) was produced in the same manner as in the production method of Production Example 1, except that the supply amounts of 1-octene and ethylene were adjusted as shown in Table 2.

[0071] <Manufacturing Example 5: Ethylene-1-octene copolymer (B-5)> Ethylene-1-octene copolymer (B-5) was produced in the same manner as in the production method of Production Example 1, except that the supply amounts of 1-octene and ethylene were adjusted as shown in Table 2.

[0072] <Manufacturing Example 6: Ethylene-1-octene copolymer (B-6)> Ethylene-1-octene copolymer (B-6) was produced in the same manner as in Production Example 1, except that the supply amounts of 1-octene and ethylene were adjusted as shown in Table 2.

[0073] <Ethylene-1-octene copolymer (b-1)> We used Dow Chemical's product, ENGAGE8842. <Ethylene-1-octene copolymer (b-2)> We used Dow Chemical's product, brand name: ENGAGE8137.

[0074] The various physical properties of the above-mentioned ethylene-1-octene copolymers (B-1) to (B-6) and ethylene-1-octene copolymers (b-1) and (b-2) were measured by the following method. The yields of ethylene-1-octene copolymers (B-1) to (B-6), as well as the results of various physical property measurements for ethylene-1-octene copolymers (B-1) to (B-6), and ethylene-1-octene copolymers (b-1) and (b-2), are shown in Table 2.

[0075] [Comonomer content (composition)] The comonomer content was measured using a nuclear magnetic resonance (NMR) analyzer (JEOL Ltd., JNM GX-400 model). 0.35 g of the sample was heated and dissolved in 2.0 mL of hexachlorobutadiene. After filtering this solution through a glass filter (G2), 0.5 mL of deuterated benzene was added, and the solution was placed in a 10 mm inner diameter NMR tube and analyzed at 120°C. 13 ¹ 13 The 1-octene content (mol%) in the ethylene-1-octene copolymer was quantified using 1C-NMR spectroscopy.

[0076] 〔density〕 Density was measured in accordance with ASTM D1505.

[0077] [MFR] In accordance with ASTM D1238, the melt flow rate (MFR) was measured under conditions of 190°C and 2.16 kg load, and 190°C and 10 kg load, respectively. 2.16 The melt flow rate (MFR) was measured under the conditions of 190°C and a 10kg load for ) 10 ) ratio (MFR 10 / MFR 2.16 ) was sought.

[0078] [Molecular weight distribution (Mw / Mn)] Gel permeation chromatography (GPC) was performed on ethylene-1-octene copolymers, and the polystyrene-equivalent molecular weight M of each fraction was determined. i-PSt We obtained M. Next, i-PSt of, [η] i-PSt ·M i-PSt =[η] i-EPR ·M i-EPR , [η] i-PSt = 1.37 × 10 -4 ×M i-PSt 0.686 , and [η] i-EPR= 7.2 × 10 -4 ×M i-EPR 0.667 Using the formula, EPR-equivalent molecular weight M i-EPR The molecular weight was converted to [a specific value]. The molecular weight distribution (Mw / Mn) was calculated using the EPR-reduced molecular weight.

[0079] Gel permeation chromatography (GPC) was performed using a Waters Alliance GPC-2000 gel permeation chromatograph as follows: The separation columns consisted of two TSKgel GNH6-HT columns and two TSKgel GNH6-HTL columns, both with a diameter of 7.5 mm and a length of 300 mm. The column temperature was 140°C. The mobile phase was o-dichlorobenzene (Fujifilm Wako Pure Chemical Industries, Ltd.) and 0.025% by mass of BHT (Takeda Pharmaceutical Company Limited) as an antioxidant, transferred at 1.0 mL / min. The sample concentration was 15 mg / 10 mL, the sample injection volume was 500 μL, and a differential refractometer was used as the detector. Standard polystyrene was measured with a molecular weight of Mw < 1000 and Mw > 4 × 10⁻⁶. 6 For this, we used a product manufactured by Tosoh Corporation, and calculated 1000 ≤ Mw ≤ 4 × 10 6 For that, we used a product manufactured by Pressure Chemical Co., Ltd.

[0080] (Peak temperature and elution amount of the composition distribution) The peak temperature and full width at half maximum of the compositional distribution were measured using a Polymer Char high-throughput compositional distribution analyzer. In a CEF (crystallization-elution-fractional chromatography) analyzer, the test specimens were conditioned at 23°C ± 2°C for more than 72 hours. Then, they were cooled from 95°C to -20°C at a rate of 1.0°C / min, and then heated to 140°C at a rate of 4.0°C / min. The peak temperature observed and the amount of elution at a temperature 20°C lower than the peak temperature were determined.

[0081] (Melting point) A DSC (Differential Scanning Calorimetry) curve was created from a test specimen that had been conditioned at 23°C ± 2°C for more than 72 hours in a DSC (Differential Scanning Calorimetry) measuring device. The specimen was cooled to -40°C, then heated to 200°C at a rate of 10°C / min, held at 200°C for 10 minutes, then cooled to -20°C at a rate of 10°C / min, held at -20°C for 1 minute, and then measured again at a rate of 10°C / min. The melting point obtained at this time was defined as Tm.

[0082] [Table 2]

[0083] [Example 1] A dry blend was prepared by mixing 65 parts by mass of a propylene polymer (A-1), 20 parts by mass of an ethylene-1-octene copolymer (B-1), and 15 parts by mass of a talc masterbatch (HG-170, manufactured by Asada Flour Milling Co., Ltd., containing talc (C-1) as an inorganic substance (C), with a talc content of 70% by mass and a carrier resin of polypropylene (MFR (230℃, 2.16kg load): 30g / 10min)) (11 parts by mass of talc) using a Henschel mixer. Next, the dry blend was fed into the main inlet of a twin-screw extruder (L / D=40, 30mmφ) set to 200°C to prepare pellets of a polypropylene resin composition. The extrusion was carried out at a screw rotation speed of 210 rpm and a discharge rate of 15 kg / hr. Injection molding was performed using the obtained polypropylene resin composition pellets to prepare test specimens (molded bodies) for physical property testing. Subsequently, the physical properties of the polypropylene resin composition and molded bodies were evaluated using the method described below. The test specimens were conditioned in a dry state at a temperature of 23°C for two days.

[0084] (1) MFR of polypropylene resin composition The melt flow rate (MFR) was measured at 230°C and under a 2.16 kg load in accordance with ASTM D1238. A higher MFR value indicates better fluidity in polypropylene resin compositions. The evaluation results are shown in Tables 3 and 4. (2) Bending test Using a 1 / 8" thick specimen, the flexural modulus (FM; kg / cm²) was measured according to ASTM D790. 2 The following parameters were measured. The evaluation results are shown in Tables 3 and 4. (3) Charpy impact test Test specimens measuring 10 mm (width) x 80 mm (length) x 4 mm (thickness) were used, and the Charpy impact strength of a notched specimen was measured at 23°C according to JIS K7111. A higher Charpy impact strength value indicates superior impact resistance. The evaluation results are shown in Tables 3 and 4.

[0085] [Examples 2-14] In Examples 2 to 14, polypropylene resin compositions were prepared in the same manner as in Example 1, except that the propylene polymer (A) and ethylene-1-octene copolymer (B) shown in Table 3 were used, and the amounts of these polymers were changed. The physical properties of the polypropylene resin composition were evaluated in the same manner as in Example 1. The results of the physical property evaluation are shown in Table 3.

[0086] [Comparative Examples 1-12] In Comparative Examples 1 to 12, polypropylene resin compositions were prepared in the same manner as in Example 1, except that ethylene-1-octene copolymers (B-3) to (B-4) or (b-1), (b-2) were used instead of ethylene-1-octene copolymer (B-1), and the amounts of the propylene polymer composition and ethylene-1-octene copolymer were set to the amounts shown in Table 4. The physical properties of the polypropylene resin composition were evaluated in the same manner as in Example 1. The results of the physical property evaluation are shown in Table 4.

[0087] [Table 3]

[0088] [Table 4]

[0089] In Tables 3 and 4, "-" indicates that the corresponding ingredient is not present. In Tables 3 and 4, the numbers in parentheses in the Talc (C-1) column and the numbers in the Component (C) column represent the values ​​excluding the polypropylene content in the talc masterbatch. Furthermore, in Tables 3 and 4, "Content when the sum of components (A), (B), and (C) is equal to 100% by mass" means the content when the sum of components (A), (B), and (C), excluding the polypropylene content in the talc masterbatch, is equal to 100% by mass.

[0090] As shown in Tables 3 and 4, Examples 1-6 exhibit a superior balance of fluidity (MFR) and room-temperature Charpy impact strength compared to Comparative Examples 1 and 2, which used the same propylene polymer (A-1). Similarly, Example 7 shows a superior balance of MFR and room-temperature Charpy impact strength compared to Comparative Examples 3 and 4, which used the same propylene polymer (A-2). Furthermore, Examples 8-13 show a superior balance of MFR and room-temperature Charpy impact strength compared to Comparative Examples 5 and 6, which used the same propylene polymer (A-3). In addition, Example 14 shows a superior balance of MFR and room-temperature Charpy impact strength compared to Comparative Examples 7 and 8, which used the same propylene polymer (A-4). Although Comparative Examples 9 and 10 use ethylene-1-octene copolymer (B-3) or (B-4), they contain a propylene polymer (a-1) with an MFR of less than 70 g / 10 min. Therefore, Comparative Example 11, which uses ethylene-1-octene copolymer (b-1), also exhibits sufficient room-temperature Charpy impact strength. However, it can be seen that the fluidity of the polypropylene resin composition in Comparative Examples 9 to 11 is lower compared to the Examples. As shown in Tables 3 and 4, the polypropylene resin compositions of Examples 1 to 14 according to the present invention exhibit superior fluidity and superior impact strength of the resulting molded articles compared to Comparative Examples 1 to 12. Furthermore, the polypropylene resin compositions according to the present invention also exhibit superior moldability.

Claims

1. 36 to 94 parts by mass of a propylene polymer (A) that satisfies the following requirements (A-a) and (A-b), 5 to 40 parts by mass of ethylene-1-octene copolymer (B) that satisfies all of the following requirements (B-a) to requirements (B-e), Inorganic substance (C) 1 to 24 parts by mass, (However, the total amount of the propylene polymer (A), ethylene-1-octene copolymer (B), and inorganic substance (C) shall be 100 parts by mass.) Propylene resin composition; Requirement (A-a): The melt flow rate (MFR) measured under conditions of 230°C and a 2.16 kg load, in accordance with ASTM D 1238, is 70–120 g / 10 min; Requirement (A-b): The intrinsic viscosity ([η]) of the decane-soluble portion of the propylene polymer (A), measured in decalin at 135°C, is 0.1 to 10.0 dl / g; Requirements (B-a): Consists of 60 to 99 mol% of constituent unit (i) derived from ethylene and 1 to 40 mol% of constituent unit (ii) derived from 1-octene [provided that the sum of constituent unit (i) and constituent unit (ii) is 100 mol%]; Requirement (B-b): Density of 850-870 kg / m³ 3 It is; Requirement (B-c): Melt flow rate (MFR) measured under conditions of 190°C and 2.16 kg load, in accordance with ASTM D 1238. 2.16 The amount is 2-20g / 10 minutes; Requirement (B-d): Melt flow rate (MFR) measured under conditions of 190°C and 2.16 kg load, in accordance with ASTM D 1238. 2.16 The melt flow rate (MFR) was measured under conditions of 190°C and 10 kg load in accordance with ASTM D1238. 10 ) ratio (MFR 10 / MFR 2.16 ) is between 6.0 and 8.0; Requirement (B-e): The amount of elution at a temperature 20°C lower than the peak temperature observed by crystallization elution fractional chromatography is less than 23% by mass of the total mass of ethylene-1-octene copolymer (B).

2. The propylene-based resin composition according to claim 1, wherein the decane-soluble portion of the propylene-based polymer (A) at room temperature (23°C) is 5% to 30% by mass relative to the total mass of the propylene-based polymer (A).

3. A pellet comprising the propylene resin composition according to claim 1 or 2.

4. A molded article comprising the propylene resin composition according to claim 1 or 2.

5. Automotive interior and exterior materials comprising the propylene resin composition described in claim 1 or 2.

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