Propylene resin composition and molded article

Abstract

A propylene resin composition according to the present invention comprises a propylene-based polymer and an inorganic component. When the propylene resin composition is heated at 600 °C for 60 minutes, the amount of ash is 0.01-25 mass%, with respect to 100 mass% of the total mass of the propylene resin composition, and when the ash is filtered twice through a metal mesh (with openings of 0.026 mm), the amount of filtration residue is 0.003-0.100 mass%. Glass fibers are included as the inorganic component and the content of the glass fibers is 0.005-0.100 mass%, with respect to 100 mass% of the total mass of the propylene resin composition.

Description

Propylene resin composition and molded article

[0001] The present invention relates to a propylene resin composition and a molded article containing the propylene resin composition.

[0002] Polypropylene has excellent moldability, rigidity, and heat resistance, and is therefore widely used in automotive parts (for example, exterior parts such as bumpers, interior parts such as door trims, instrument panels, and airbag covers), and housings for household electrical appliances.

[0003] In recent years, there has been a growing demand for material recycling, which involves reusing waste plastics as raw materials for plastic products. For example, Patent Document 1 describes that a stretched sheet containing polypropylene resin and an inorganic filler is ideal for recycling as it can reduce environmental impact.

[0004] International Publication No. 2023 / 127973

[0005] Incidentally, airbag covers, one of the applications for automotive parts, have a thin-walled structure called a tear line, which is grooved in shape. The structure is designed so that only the tear line area ruptures due to the inflation force of the airbag, allowing the airbag to deploy. However, conventional molded articles containing propylene resin compositions have relatively high tear strength, so the tearability of the tear line area is not sufficient. Furthermore, the molded article is also required to have a smooth surface.

[0006] The present invention has been made in view of these problems, and aims to provide a propylene resin composition that can produce a molded article having relatively low tear strength and a relatively smooth surface, and a molded article containing the propylene resin composition.

[0007] The propylene resin composition according to the present invention comprises a propylene polymer and an inorganic component, wherein the amount of ash content when heated at 600°C for 60 minutes is 0.01% by mass or more and 25% by mass or less, based on 100% by mass of the total mass of the propylene resin composition, and the amount of ash filtration residue when the ash content is filtered twice through a metal mesh (mesh opening 0.026 mm) is 0.003% by mass or more and 0.100% by mass or less, and the inorganic component includes glass fibers, the content of which is 0.005% by mass or more and 0.100% by mass or less, based on 100% by mass of the total mass of the propylene resin composition.

[0008] The molded article according to the present invention contains the above-described propylene resin composition.

[0009] According to the present invention, it is possible to provide a propylene resin composition that can produce a molded article having relatively low tear strength and a relatively smooth surface, and a molded article containing the propylene resin composition.

[0010] The following describes embodiments of the present invention, but the present invention is not limited to the following embodiments.

[0011] [Propylene Resin Composition] The propylene resin composition according to this embodiment comprises a propylene polymer and an inorganic component.

[0012] <Propylene-based polymers> Propylene-based polymers are polymers containing 50% by mass or more monomer units derived from propylene. Examples of propylene-based polymers include propylene homopolymers, random copolymers of propylene and monomers other than propylene, and heterophagic propylene polymerization materials. From the viewpoint of improving the rigidity and impact resistance of the molded article, the propylene resin composition according to this embodiment preferably contains a heterophagic propylene polymerization material as the propylene-based polymer. The propylene resin composition according to this embodiment may contain only one type of propylene-based polymer, or it may contain two or more types.

[0013] The isotactic pentad fraction of the propylene polymer is preferably 0.961 or higher, more preferably 0.965 or higher, and even more preferably 0.968 or higher. Furthermore, the isotactic pentad fraction of the propylene polymer is preferably 1.000 or lower, and more preferably 0.995 or lower.

[0014] The isotactic pentad fraction refers to the isotactic fraction in pentad units. In other words, the isotactic pentad fraction indicates the proportion of structures in which five monomer units derived from propylene are consecutively linked by mesobonding, when viewed in pentad units. If the component in question is a copolymer, it refers to the value measured for the chain of monomer units derived from propylene.

[0015] The isotactic pentad fraction is, １３ This is a value measured by a C-NMR spectrum. Specifically, １３ The ratio of the area of ​​the mmmm peak to the area of ​​the total absorption peak in the methyl carbon region obtained by C-NMR spectroscopy is defined as the isotactic pentad fraction. １３ A method for measuring the isotactic pentad fraction using C-NMR spectroscopy is described, for example, in Macromolecules, 6, 925 (1973) by A. Zambelli et al. However, １３ The assignment of absorption peaks obtained by C-spectroscopy shall be based on the description in Macromolecules, 8, 687 (1975).

[0016] The isotactic pentad fraction of propylene polymers can be adjusted to the above range by appropriately selecting the catalyst, donor, polymerization conditions, etc. Furthermore, propylene polymers with the desired isotactic pentad fraction can be obtained from commercially available products.

[0017] The content of the propylene polymer is preferably 75.000% by mass or more, and more preferably 80.000% by mass or more, based on 100% by mass of the total mass of the propylene resin composition. Furthermore, the content of the propylene polymer is preferably 99.995% by mass or less, and more preferably 99.900% by mass or less, based on 100% by mass of the total mass of the propylene resin composition.

[0018] (Propylene homopolymer) The propylene homopolymer has an intrinsic viscosity number ([η]) of 0.10 dL / g or more and 4.00 dL / g or less, more preferably 0.50 dL / g or more and 3.00 dL / g or less, and even more preferably 0.70 dL / g or more and 2.00 dL / g or less, from the viewpoint of improving the fluidity of the propylene resin composition when melted and the toughness of the molded article.

[0019] In this specification, the intrinsic viscosity number (unit: dL / g) is a value measured at a temperature of 135°C using tetralin as the solvent by the following method.

[0020] The reduced viscosity is measured at three points using an Ubbelohde viscometer at concentrations of 0.1 g / dL, 0.2 g / dL, and 0.5 g / dL. The reduced viscosity is plotted against the concentration, and the intrinsic viscosity number is determined by extrapolation, where the concentration is extrapolated to zero. The method for calculating the intrinsic viscosity number by extrapolation is described, for example, on page 491 of "Polymer Solutions, Polymer Experiments 11" (Kyoritsu Shuppan Co., Ltd., 1982).

[0021] The molecular weight distribution (Mw / Mn) of the propylene homopolymer is preferably 3.0 or higher, and more preferably 4.0 or higher. The molecular weight distribution of the propylene homopolymer is preferably 15.0 or lower, and more preferably 10.0 or lower. The molecular weight distribution of the propylene homopolymer is preferably 3.0 or higher and 15.0 or lower, and more preferably 4.0 or higher and 10.0 or lower.

[0022] In this specification, molecular weight distribution refers to the ratio of weight-average molecular weight (Mw) to number-average molecular weight (Mn) (Mw / Mn), calculated using the weight-average molecular weight (Mw) and number-average molecular weight (Mn) measured by gel permeation chromatography (GPC) under the following conditions: Apparatus: Tosoh Corporation HLC-8121 GPC / HT Separation column: Tosoh Corporation GMHHR-H(S)HT 3 columns Measurement temperature: 140°C Carrier: Orthodichlorobenzene Flow rate: 1.0 mL / min Sample concentration: Approximately 1 mg / mL Sample injection volume: 400 μL Detector: Differential refraction Calibration curve preparation method: Standard polystyrene is used

[0023] Propylene homopolymers can be produced, for example, by carrying out a polymerization process in which propylene is polymerized using a polymerization catalyst.

[0024] Examples of polymerization catalysts include Ziegler-type catalysts; Ziegler-Natta-type catalysts; catalysts containing compounds of Group 4 transition metals having a cyclopentadienyl ring and alkylaluminoxanes; catalysts containing compounds of Group 4 transition metals having a cyclopentadienyl ring, compounds that react with the transition metal compounds to form ionic complexes, and organoaluminum compounds; and catalysts modified by supporting catalyst components (compounds of Group 4 transition metals having a cyclopentadienyl ring, compounds that form ionic complexes, organoaluminum compounds, etc.) on inorganic particles (silica, clay minerals, etc.).

[0025] Examples of the polymerization catalyst include catalysts described in Japanese Patent Publication No. 61-218606, Japanese Patent Publication No. 5-194685, Japanese Patent Publication No. 7-216017, Japanese Patent Publication No. 9-316147, Japanese Patent Publication No. 10-212319, Japanese Patent Publication No. 2004-182981, Japanese Patent Publication No. 2010-168545, Japanese Patent Publication No. 2011-246699, and the like.

[0026] Furthermore, a polymer obtained by prepolymerizing propylene in the presence of the polymerization catalyst can also be used as the polymerization catalyst.

[0027] Polymerization methods include, for example, bulk polymerization, solution polymerization, and gas-phase polymerization. Here, bulk polymerization refers to a method in which polymerization is carried out using liquid olefins at the polymerization temperature as a medium. Solution polymerization refers to a method in which polymerization is carried out in an inert hydrocarbon solvent such as propane, butane, isobutane, pentane, hexane, heptane, and octane. Gas-phase polymerization refers to a method in which a monomer in a gaseous state is used as a medium to polymerize a monomer in a gaseous state within that medium.

[0028] Polymerization methods include, for example, batch, continuous, and combinations thereof. The polymerization method may also be a multi-stage system in which multiple polymerization reactors are connected in series.

[0029] From an industrial and economically superior viewpoint, the polymerization method is preferably a continuous gas-phase polymerization method, or a bulk-gas-phase polymerization method that sequentially performs bulk polymerization and gas-phase polymerization.

[0030] The various conditions in the polymerization process (polymerization temperature, polymerization pressure, monomer concentration, catalyst input amount, polymerization time, etc.) should be appropriately determined according to the molecular structure of the target polymer.

[0031] In the method for producing a propylene homopolymer, other steps may be performed before or after the polymerization step. For example, after the polymerization step, the polymer may be dried at a temperature below the melting point of the polymer, if necessary, in order to remove residual solvents contained in the polymer, ultra-low molecular weight oligomers produced as by-products during manufacturing, etc. Examples of drying methods include those described in Japanese Patent Publication No. 55-75410 and Japanese Patent No. 2565753.

[0032] (Random copolymer of propylene and monomers other than propylene) A random copolymer of propylene and monomers other than propylene contains monomer units derived from propylene and monomer units derived from monomers other than propylene. The random copolymer preferably contains 0.01% to 20% by mass of monomer units derived from monomers other than propylene, based on 100% by mass of the total mass of the copolymer.

[0033] Examples of monomers other than propylene include ethylene and α-olefins having 4 to 12 carbon atoms. In this specification, α-olefins are aliphatic unsaturated hydrocarbons having a carbon-carbon unsaturated double bond at the α-position. Examples of α-olefins having 4 to 12 carbon atoms include 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-nonene, 1-decene, 1-dodecene, 4-methyl-1-pentene, and 4-methyl-1-hexene.

[0034] The monomer other than propylene is preferably at least one selected from the group consisting of ethylene and α-olefins having 4 to 10 carbon atoms, more preferably at least one selected from the group consisting of ethylene, 1-butene, 1-hexene and 1-octene, and even more preferably at least one selected from the group consisting of ethylene and 1-butene.

[0035] Examples of random copolymers of propylene and monomers other than propylene include propylene-ethylene random copolymer, propylene-1-butene random copolymer, propylene-1-hexene random copolymer, propylene-1-octene random copolymer, propylene-ethylene-1-butene random copolymer, propylene-ethylene-1-hexene random copolymer, and propylene-ethylene-1-octene random copolymer.

[0036] A random copolymer of propylene and a monomer other than propylene has an intrinsic viscosity number ([η]) of 0.10 dL / g or more and 4.00 dL / g or less, more preferably 0.50 dL / g or more and 3.00 dL / g or less, and even more preferably 0.70 dL / g or more and 2.00 dL / g or less, from the viewpoint of improving the fluidity of the propylene resin composition when melted.

[0037] The molecular weight distribution (Mw / Mn) of the random polymer of propylene and monomers other than propylene is preferably 3.0 or more, more preferably 4.0 or more. The molecular weight distribution of the random polymer of propylene and monomers other than propylene is preferably 10.0 or less, more preferably 7.0 or less. The molecular weight distribution of the random polymer of propylene and monomers other than propylene is preferably from 3.0 to 10.0, more preferably from 4.0 to 7.0.

[0038] The random copolymer of propylene and monomers other than propylene can be produced, for example, by polymerizing propylene and monomers other than propylene according to the polymerization catalyst, polymerization method, polymerization mode, and polymerization conditions that can be used in the production of the above-described propylene homopolymer.

[0039] (Heterophasic propylene polymerization material) The heterophasic propylene polymerization material is a mixture containing a polymer I containing 80% by mass or more of monomer units derived from propylene (where the total mass of the polymer I is 100% by mass), and a polymer II containing monomer units derived from at least one α-olefin selected from the group consisting of ethylene and α-olefins having 4 to 12 carbon atoms and monomer units derived from propylene.

[0040] The heterophasic propylene polymerization material can be produced, for example, by performing a first polymerization step of polymerizing the polymer I and a second polymerization step of polymerizing the polymer II. These polymerization steps can be carried out according to the polymerization catalyst, polymerization method, polymerization mode, and polymerization conditions that can be used in the production of the above-described propylene homopolymer.

[0041] In the heterophasic propylene polymerization material, the total of the polymer I and the polymer II contained in the heterophasic propylene polymerization material may be 100% by mass based on 100% by mass of the total mass of the heterophasic propylene polymerization material.

[0042] As described above, the polymer I contains 80% by mass or more of monomer units derived from propylene (however, the total mass of the polymer I is taken as 100% by mass). The polymer I may be, for example, a propylene homopolymer, or may contain monomer units derived from monomers other than propylene. When the polymer I contains monomer units derived from monomers other than propylene, the content may be, for example, 0.01% by mass or more and less than 20% by mass based on 100% by mass of the total mass of the polymer I.

[0043] Examples of monomers other than propylene include ethylene and α-olefins having 4 or more carbon atoms. Examples of α-olefins having 4 or more carbon atoms include 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-nonene, 1-decene, 1-dodecene, 4-methyl-1-pentene, 4-methyl-1-hexene, and the like.

[0044] The monomer other than propylene is preferably at least one selected from the group consisting of ethylene and α-olefins having 4 to 10 carbon atoms, more preferably at least one selected from the group consisting of ethylene, 1-butene, 1-hexene, and 1-octene, and even more preferably at least one selected from the group consisting of ethylene and 1-butene.

[0045] Examples of the polymer I containing monomer units derived from monomers other than propylene include propylene-ethylene copolymers, propylene-1-butene copolymers, propylene-1-hexene copolymers, propylene-1-octene copolymers, propylene-ethylene-1-butene copolymers, propylene-ethylene-1-hexene copolymers, propylene-ethylene-1-octene copolymers, and the like.

[0046] From the viewpoint of improving the dimensional stability of the molded body, the polymer I is preferably a propylene homopolymer, a propylene-ethylene copolymer, a propylene-1-butene copolymer, or a propylene-ethylene-1-butene copolymer, and more preferably a propylene homopolymer.

[0047] The isotactic pentad fraction of polymer I is preferably 1.000 or less, and may be, for example, 0.998 or less, 0.995 or less, 0.990 or less, or 0.985 or less. The lower limit of the isotactic pentad fraction is not particularly limited, but may be, for example, 0.900 or more, 0.925 or more, 0.930 or more, 0.961 or more, 0.965 or more, or 0.968 or more.

[0048] The content of polymer I is preferably 50% to 99% by mass, and more preferably 60% to 95% by mass, based on 100% by mass of the total mass of the heterophagic propylene polymerization material.

[0049] As described above, polymer II contains monomer units derived from ethylene and at least one α-olefin selected from the group consisting of α-olefins having 4 to 12 carbon atoms, and monomer units derived from propylene. Examples of α-olefins having 4 to 12 carbon atoms include 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-nonene, 1-decene, 1-dodecene, 4-methyl-1-pentene, and 4-methyl-1-hexene.

[0050] Polymer II preferably contains 30% by mass or more monomer units derived from ethylene and at least one α-olefin selected from the group consisting of α-olefins having 4 to 12 carbon atoms, and also contains monomer units derived from propylene (provided the total mass of Polymer II is 100% by mass).

[0051] In polymer II, the content of monomer units derived from ethylene and at least one α-olefin selected from the group consisting of α-olefins having 4 to 12 carbon atoms may be 30% by mass or more and 70% by mass or less, or 35% by mass or more and 60% by mass or less (provided that the total mass of polymer II is 100% by mass).

[0052] In polymer II, the at least one α-olefin selected from the group consisting of ethylene and α-olefins having 4 to 12 carbon atoms is preferably at least one selected from the group consisting of ethylene and α-olefins having 4 to 10 carbon atoms, more preferably at least one selected from the group consisting of ethylene, 1-butene, 1-hexene, 1-octene and 1-decene, and even more preferably at least one selected from the group consisting of ethylene and 1-butene.

[0053] Examples of polymer II include propylene-ethylene copolymer, propylene-ethylene-1-butene copolymer, propylene-ethylene-1-hexene copolymer, propylene-ethylene-1-octene copolymer, propylene-ethylene-1-decene copolymer, propylene-1-butene copolymer, propylene-1-hexene copolymer, propylene-1-octene copolymer, and propylene-1-decene copolymer. Among these, polymer II is preferably propylene-ethylene copolymer, propylene-1-butene copolymer, or propylene-ethylene-1-butene copolymer, and more preferably propylene-ethylene copolymer.

[0054] The content of polymer II is preferably 1% to 50% by mass, and more preferably 5% to 40% by mass, based on 100% by mass of the total mass of the heterophagic propylene polymerization material.

[0055] In the heterophagic propylene polymerization material, the content of monomer units derived from ethylene and at least one α-olefin selected from the group consisting of α-olefins having 4 to 12 carbon atoms may be 0.3% by mass or more and 35% by mass or less, or 0.7% by mass or more and 24% by mass or less (provided that the total mass of the heterophagic propylene polymerization material is 100% by mass).

[0056] The content of xylene-insoluble components (CXIS components) in the heterophagic propylene polymerization material is preferably 50% to 99% by mass, and more preferably 60% to 95% by mass, based on 100% by mass of the total mass of the heterophagic propylene polymerization material.

[0057] The content of xylene-soluble components (CXS components) in the heterophagic propylene polymerization material is preferably 1% to 50% by mass, and more preferably 5% to 40% by mass, based on 100% by mass of the total mass of the heterophagic propylene polymerization material.

[0058] In this specification, xylene-insoluble components (CXIS components) refer to components insoluble in p-xylene contained in the polymer, and the solids obtained by the following method: a method in which approximately 2 g of polymer is dissolved in boiling p-xylene for 2 hours to obtain a solution, and then the solution is cooled to 20°C to precipitate the solids.

[0059] Furthermore, in this specification, xylene-soluble components (CXS components) refer to components in the polymer other than the "CXIS components".

[0060] In this embodiment, the CXIS component in the heterophagic propylene polymerization material is considered to be mainly composed of polymer I, and the CXS component in the heterophagic propylene polymerization material is considered to be mainly composed of polymer II.

[0061] Examples of heterophagic propylene polymerization materials include (propylene)-(propylene-ethylene) polymerization materials, (propylene)-(propylene-ethylene-1-butene) polymerization materials, (propylene)-(propylene-ethylene-1-hexene) polymerization materials, (propylene)-(propylene-ethylene-1-octene) polymerization materials, (propylene)-(propylene-1-butene) polymerization materials, (propylene)-(propylene-1-hexene) polymerization materials, (propylene)-(propylene-1-octene) polymerization materials, (propylene)-(propylene- 1-decene) polymerization material, (propylene-ethylene)-(propylene-ethylene) polymerization material, (propylene-ethylene)-(propylene-ethylene-1-butene) polymerization material, (propylene-ethylene)-(propylene-ethylene-1-hexene) polymerization material, (propylene-ethylene)-(propylene-ethylene-1-octene) polymerization material, (propylene-ethylene)-(propylene-ethylene-1-decene) polymerization material, (propylene-ethylene)-(propylene-1-butene) polymerization material, (propylene-ethylene)-(propylene-1-hexene) (Cen) polymerization material, (propylene-ethylene)-(propylene-1-octene) polymerization material, (propylene-ethylene)-(propylene-1-decene) polymerization material, (propylene-1-butene)-(propylene-ethylene) polymerization material, (propylene-1-butene)-(propylene-ethylene-1-butene) polymerization material, (propylene-1-butene)-(propylene-ethylene-1-hexene) polymerization material, (propylene-1-butene)-(propylene-ethylene-1-octene) polymerization material, (propylene-1-butene)-(propylene-ethylene- 1-decene) polymerization material, (propylene-1-butene)-(propylene-1-butene) polymerization material, (propylene-1-butene)-(propylene-1-hexene) polymerization material, (propylene-1-butene)-(propylene-1-octene) polymerization material, (propylene-1-butene)-(propylene-1-decene) polymerization material, (propylene-1-hexene)-(propylene-1-hexene) polymerization material, (propylene-1-hexene)-(propylene-1-octene) polymerization material, (propylene-1-hexene)-(propylene-1-decene) polymerization material,Examples include (propylene-1-octene)-(propylene-1-octene) polymerization materials and (propylene-1-octene)-(propylene-1-decene) polymerization materials.

[0062] Here, the description "(propylene)-(propylene-ethylene) polymerization material" means "a heterophagous propylene polymerization material in which polymer I is a propylene homopolymer and polymer II is a propylene-ethylene copolymer." The same applies to other similar expressions.

[0063] The heterophagic propylene polymerization material is preferably a (propylene)-(propylene-ethylene) polymerization material, a (propylene)-(propylene-ethylene-1-butene) polymerization material, a (propylene-ethylene)-(propylene-ethylene) polymerization material, a (propylene-ethylene)-(propylene-ethylene-1-butene) polymerization material, or a (propylene-1-butene)-(propylene-1-butene) polymerization material, and more preferably a (propylene)-(propylene-ethylene) polymerization material.

[0064] The intrinsic viscosity number ([η]I) of polymer I is preferably 0.10 dL / g or more and 4.00 dL / g or less, more preferably 0.50 dL / g or more and 3.00 dL / g or less, and even more preferably 0.70 dL / g or more and 2.00 dL / g or less.

[0065] The intrinsic viscosity number ([η]II) of polymer II is preferably 1.00 dL / g or more and 10.00 dL / g or less, more preferably 2.00 dL / g or more and 10.00 dL / g or less, and even more preferably 2.00 dL / g or more and 9.00 dL / g or less.

[0066] Furthermore, the ratio of the intrinsic viscosity number of polymer II ([η]II) to the intrinsic viscosity number of polymer I ([η]I) ([η]II / [η]I) is preferably 1 or more and 20 or less, and more preferably 1 or more and 10 or less.

[0067] One method for measuring the intrinsic viscosity number ([η]I) of polymer I is to extract the polymerized polymer I from the reactor in which polymer I is polymerized and measure the intrinsic viscosity number of the polymer.

[0068] The intrinsic viscosity number of polymer II ([η]II) can be calculated, for example, using the intrinsic viscosity number of the heterophagic propylene polymerization material ([η]Total), the intrinsic viscosity number of polymer I ([η]I), and the content of polymer II and polymer I, by the following formula (i).

[0069] [η]II = ([η]Total - [η]I × XI) / XII ... (i) [η]Total: Intrinsic viscosity number of the heterophagic propylene polymerization material (dL / g) [η]I: Intrinsic viscosity number of polymer I (dL / g) XI: Ratio of the mass of polymer I to the total mass of the heterophagic propylene polymerization material (mass of polymer I / mass of heterophagic propylene polymerization material) XII: Ratio of the mass of polymer II to the total mass of the heterophagic propylene polymerization material (mass of polymer II / mass of heterophagic propylene polymerization material)

[0070] Here, XI and XII can be determined from the mass balance during polymerization.

[0071] Furthermore, XII may be calculated by measuring the heat of fusion of polymer I and the heterophagic propylene polymerization material and using the following formula: XII = 1 - (ΔHf)T / (ΔHf)P (ΔHf)T: Heat of fusion of heterophagic propylene polymerization material (J / g) (ΔHf)P: Heat of fusion of polymer I (J / g)

[0072] The intrinsic viscosity number ([η]CXIS) of the CXIS component is preferably 0.10 dL / g or more and 4.00 dL / g or less, more preferably 0.50 dL / g or more and 3.00 dL / g or less, and even more preferably 0.70 dL / g or more and 2.00 dL / g or less.

[0073] The intrinsic viscosity number ([η]CXS) of the CXS component is preferably 1.00 dL / g or more and 10.00 dL / g or less, more preferably 2.00 dL / g or more and 10.00 dL / g or less, and even more preferably 2.00 dL / g or more and 9.00 dL / g or less.

[0074] The ratio of the intrinsic viscosity number of the CXS component ([η]CXS) to the intrinsic viscosity number of the CXIS component ([η]CXIS) ([η]CXS / [η]CXIS) is preferably 1 or more and 20 or less, and more preferably 1 or more and 10 or less.

[0075] The molecular weight distribution (Mw(I) / Mn(I)) of polymer I is preferably 3.0 or higher, and more preferably 4.0 or higher.

[0076] The molecular weight distribution of the CXIS component (Mw(CXIS) / Mn(CXIS)) is preferably 3.0 or higher, and more preferably 4.0 or higher.

[0077] The melt flow rate (MFR) of the propylene polymer is preferably 0.1 g / 10 min or more, and more preferably 1 g / 10 min or more and 300 g / 10 min or less, from the viewpoint of improving the moldability of the propylene resin composition. The melt flow rate (MFR) of the propylene polymer may be 5 g / 10 min or more and 100 g / 10 min or less, or 10 g / 10 min or more and 50 g / 10 min or less.

[0078] In this specification, the melt flow rate (MFR) of propylene polymers is measured by Method A, under the conditions of a temperature of 230°C and a load of 2.16 kg, in accordance with the method specified in JIS K7210-1995.

[0079] The propylene resin composition according to this embodiment may include recycled heterophagic propylene polymerization material as a propylene polymer. Recycled heterophagic propylene polymerization material refers to heterophagic propylene polymerization material that is reused after undergoing processing such as molding, or after being used for some final purpose, through a recovery process. The same applies to other "recycled xxx" materials.

[0080] <Inorganic Components> Examples of inorganic components include talc, glass fiber, glass wool, rock wool, silicon dioxide, titanium dioxide, iron oxide, aluminum oxide, magnesium oxide, antimony oxide, barium ferrite, strontium ferrite, beryllium oxide, magnesium hydroxide, aluminum hydroxide, basic magnesium carbonate, calcium carbonate, magnesium carbonate, carbonate minerals, calcium sulfate, magnesium sulfate, basic magnesium sulfate, calcium sulfite, carbon black, cadmium sulfide, quartz powder, diatomaceous earth, white carbon, kaolin clay, calcined clay, mica, bentonite, wollastonite, zeolite, hydrotalcite, dolomite, barite, gypsum, potassium titanate, etc. The propylene resin composition according to this embodiment contains glass fiber as an inorganic component. In one embodiment, the propylene resin composition according to this embodiment also contains talc and glass fiber as inorganic components.

[0081] (Talc) Talc is a hydrated magnesium silicate with a pyrophyllite-type three-layered crystalline structure.

[0082] Talc is preferably obtained by grinding hydrated magnesium silicate, and more preferably by finely grinding the molecular crystals of hydrated magnesium silicate to about a unit layer to obtain flat particles.

[0083] The average particle size of talc is preferably 3 μm or less. Here, the average particle size of talc refers to the 50% equivalent particle size D50, which is obtained from the integral distribution curve obtained by the sieving method when the talc is suspended in a dispersion medium of water or alcohol using a centrifugal sedimentation particle size distribution analyzer.

[0084] Talc may be used untreated, or its surface may be treated with various known surfactants to improve interfacial adhesion with propylene polymers or to improve dispersibility in propylene polymers. Examples of surfactants include silane coupling agents, titanium coupling agents, higher fatty acids, higher fatty acid esters, higher fatty acid amides, and higher fatty acid salts.

[0085] From the viewpoint of obtaining good mechanical strength for automotive materials, industrial materials, etc., while keeping costs down, the talc content is 0.1% to 50% by mass, preferably 0.1% to 40% by mass, more preferably 0.1% to 30% by mass, and even more preferably 0.1% to 25% by mass, based on 100% by mass of the total mass of the propylene resin composition.

[0086] (Glass Fibers) The material of the glass fibers is not particularly limited, and any glass can be used. Examples of glass fiber materials include E glass (alkali-free glass), A glass, C glass, S glass, D glass, etc., with E glass being preferred among these. As for the glass fibers, those manufactured by any manufacturing method can be used.

[0087] As the glass fiber, glass wool may be used, or glass fiber obtained by cutting glass strands, known as chopped strands, may be used. From the viewpoint of further enhancing the effect of improving the rigidity and impact strength of the molded article containing the propylene resin composition, chopped strands are preferably used. Commercially available glass fibers can be used.

[0088] The average fiber diameter of the glass fibers may be 3 μm or more, or 25 μm or less. Preferably, the average fiber diameter of the glass fibers is 5 μm or more, more preferably 8 μm or more, more preferably 20 μm or less, and more preferably 16 μm or less.

[0089] The weight-average fiber length of the glass fiber is preferably 100 μm or more, and more preferably 200 μm or more. The weight-average fiber length of the glass fiber is preferably 2000 μm or less, and more preferably 1000 μm or less.

[0090] The aspect ratio (weight-average fiber length / average fiber diameter) of the glass fiber may be 20 or more, or 60 or less. Preferably, the aspect ratio of the glass fiber is 25 or more, more preferably 30 or more, preferably 58 or less, and more preferably 55 or less.

[0091] The average fiber diameter, weight-average fiber length, and aspect ratio of the glass fibers contained in the propylene resin composition can be measured by the following method.

[0092] Two g of propylene resin composition is dissolved in boiling p-xylene for two hours to obtain a xylene-insoluble component containing glass fibers. Next, the glass fibers in the xylene-insoluble component are observed using a microscope, and the length and diameter of 200 glass fibers are measured. The weight-average fiber length and average fiber diameter of the 200 glass fibers are calculated, and the ratio of the weight-average fiber length to the average fiber diameter is taken as the aspect ratio of the glass fibers contained in the propylene resin composition.

[0093] The glass fibers contained in the propylene resin composition may be a combination of two or more types of glass fibers in any ratio. Therefore, as the glass fibers used as a raw material for the propylene resin composition, one type of glass fiber may be used, or a combination of two or more types of glass fibers in any ratio may be used.

[0094] Glass fibers may be treated with a sizing agent and / or a surface treatment agent. Preferably, the glass fibers are surface-treated with a surface treatment agent from the viewpoint of improving dispersibility in propylene polymers. Examples of surface treatment agents include organosilane coupling agents, titanate coupling agents, aluminate coupling agents, zirconate coupling agents, silicone compounds, higher fatty acids, fatty acid metal salts, fatty acid esters, and the like.

[0095] Examples of organosilane coupling agents include vinyltrimethoxysilane, γ-chloropropyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-aminopropyltrimethoxysilane, and 3-acryloxypropyltrimethoxysilane.

[0096] Examples of titanate coupling agents include isopropyltriisostearoyl titanate, isopropyltris(dioctyl pyrophosphate) titanate, and isopropyltri(N-aminoethyl) titanate.

[0097] Examples of aluminate coupling agents include acetalkoxyaluminum diisopropylate.

[0098] Examples of zirconate coupling agents include tetra(2,2-diallyloxymethyl)butyl, di(tridecyl)phosphite zirconate, and neopentyl(diallyl)oxytrineodecanoyl zirconate.

[0099] Examples of the aforementioned silicone compound include silicone oil and silicone resin.

[0100] Examples of high-grade fatty acids include oleic acid, capric acid, lauric acid, palmitic acid, stearic acid, montanic acid, linoleic acid, rosinic acid, linolenic acid, undecanoic acid, and undecenoic acid.

[0101] Examples of higher fatty acid metal salts include sodium salts, lithium salts, calcium salts, magnesium salts, zinc salts, and aluminum salts of fatty acids with nine or more carbon atoms (e.g., stearic acid, montanic acid). Among these, the higher fatty acid metal salts are preferably calcium stearate, aluminum stearate, calcium montanate, or sodium montanate.

[0102] Examples of fatty acid esters include polyhydric alcohol fatty acid esters such as glycerin fatty acid esters, alpha-sulfo fatty acid esters, polyoxyethylene sorbitan fatty acid esters, sorbitan fatty acid esters, polyethylene fatty acid esters, and sucrose fatty acid esters.

[0103] The amount of the surface treatment agent used is not particularly limited, but is preferably 0.01 parts by mass or more and 5 parts by mass or less, and more preferably 0.1 parts by mass or more and 3 parts by mass or less, per 100 parts by mass of glass fiber.

[0104] Glass fibers may be treated with a sizing agent. Treatment with a sizing agent can bind the glass fibers together. Examples of sizing agents include epoxy sizing agents, aromatic urethane sizing agents, aliphatic urethane sizing agents, acrylic sizing agents, and maleic anhydride-modified polyolefin sizing agents. The sizing agent preferably melts at the temperature of melt kneading with the olefin polymer A, and more preferably melts at 200°C or below.

[0105] From the viewpoint of obtaining a molded article with low tear strength and a smooth surface, the glass fiber content is 0.005% by mass or more and 0.100% by mass or less, and preferably 0.005% by mass or more and 0.05% by mass or less, based on 100% by mass of the total mass of the propylene resin composition.

[0106] <Ethylene-α-olefin copolymer> In one embodiment, the propylene resin composition according to this embodiment further comprises an ethylene-α-olefin copolymer. The propylene resin composition according to this embodiment may also contain recycled ethylene-α-olefin copolymer as the ethylene-α-olefin copolymer.

[0107] The ethylene-α-olefin copolymer may also be an ethylene-α-olefin random copolymer. Note that the ethylene-α-olefin copolymer is a copolymer containing monomer units derived from ethylene and monomer units derived from α-olefins having four or more carbon atoms, and substantially free of monomer units derived from propylene.

[0108] The ethylene-α-olefin copolymer may have a total content of monomer units derived from ethylene and monomer units derived from α-olefins having 4 or more carbon atoms, which may be 100% by mass, based on 100% by mass of the total mass of the copolymer.

[0109] Examples of the α-olefin having 4 or more carbon atoms include α-olefins having 4 to 12 carbon atoms. Examples of the α-olefin having 4 to 12 carbon atoms include 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-octene, 1-decene, and the like. The α-olefin having 4 to 12 carbon atoms is preferably 1-butene, 1-hexene, or 1-octene. The α-olefin having 4 to 12 carbon atoms may be an α-olefin having a cyclic structure such as vinylcyclopropane or vinylcyclobutane.

[0110] Examples of the ethylene-α-olefin copolymer include an ethylene-1-butene copolymer, an ethylene-1-hexene copolymer, an ethylene-1-octene copolymer, an ethylene-1-decene copolymer, an ethylene-(3-methyl-1-butene) copolymer, a copolymer of ethylene and an α-olefin having a cyclic structure, and the like.

[0111] In the ethylene-α-olefin copolymer, the content of the monomer unit derived from the α-olefin having 4 or more carbon atoms is preferably 1% by mass or more and 49% by mass or less, more preferably 5% by mass or more and 49% by mass or less, and still more preferably 24% by mass or more and 49% by mass or less with respect to 100% by mass of the total mass of the ethylene-α-olefin copolymer.

[0112] The density of the ethylene-α-olefin copolymer is preferably 0.850 g / cm ３ or more and 0.890 g / cm ３ or less, more preferably 0.850 g / cm ３ or more and 0.880 g / cm ３ or less, and still more preferably 0.850 g / cm ３ or more and 0.870 g / cm ３ or less from the viewpoint of the impact resistance of the molded body.

[0113] The melt flow rate of the ethylene-α-olefin copolymer at a temperature of 190°C and a load of 2.16 kg is preferably 0.1 g / 10 min or more and 80 g / 10 min or less. The melt flow rate of the ethylene-α-olefin copolymer can be measured by Method A at a temperature of 190°C and a load of 2.16 kg, according to the method specified in JIS K7210-1995.

[0114] The content of ethylene-α-olefin copolymer is preferably 1% by mass or more, and more preferably 5% by mass or more, based on 100% by mass of the total mass of the propylene resin composition. Furthermore, the content of ethylene-α-olefin copolymer is preferably 40% by mass or less, and more preferably 30% by mass or less, based on 100% by mass of the total mass of the propylene resin composition.

[0115] Ethylene-α-olefin copolymers can be produced by polymerizing ethylene and α-olefins having four or more carbon atoms using a polymerization catalyst.

[0116] Examples of polymerization catalysts include homogeneous catalysts such as metallocene catalysts and Ziegler-Natta type catalysts.

[0117] Examples of homogeneous catalysts include catalysts containing compounds of Group 4 transition metals having a cyclopentadienyl ring and alkylaluminoxanes; catalysts containing compounds of Group 4 transition metals having a cyclopentadienyl ring, compounds that react with the transition metal compounds to form ionic complexes, and organoaluminum compounds; and catalysts modified by supporting catalyst components (compounds of Group 4 transition metals having a cyclopentadienyl ring, compounds that form ionic complexes, organoaluminum compounds, etc.) on inorganic particles (silica, clay minerals, etc.).

[0118] Examples of Ziegler-Natta type catalysts include catalysts that combine a titanium-containing solid transition metal component with an organometallic component.

[0119] Commercially available ethylene-α-olefin copolymers may be used. Examples of commercially available ethylene-α-olefin copolymers include Engage® manufactured by Dow Chemical Japan Ltd., Tuffmer® manufactured by Mitsui Chemicals, Inc., Neozex® and Ultzex® manufactured by Prime Polymer Co., Ltd., and Excellen FX®, Sumikasen®, and Esprene SPO® manufactured by Sumitomo Chemical Co., Ltd.

[0120] The propylene resin composition according to this embodiment may contain other components besides those listed above. Other components may include, for example, organic fillers, thermoplastic resins (polystyrenes (e.g., polystyrene, poly(p-methylstyrene), poly(α-methylstyrene), AS (acrylonitrile / styrene copolymer) resin), ABS (acrylonitrile / butadiene / styrene copolymer) resin, AAS (special acrylic rubber / acrylonitrile / styrene copolymer) resin, ACS (acrylonitrile / chlorinated polyethylene / styrene copolymer) resin, polychloroprene, chlorinated rubber, polyvinyl chloride, polyvinylidene chloride, acrylic resins, ethylene / vinyl alcohol copolymer resins, fluororesins, polyacetals, grafted polyphenylene ether resins and polyphenylene sulfide resins, polyurethanes, polyamides, and polyester resins (e.g., polyethylene terephthalate, polybutylene terephthalate)). Examples include polycarbonate, polysulfone, polyetheretherketone, polyethersulfone, aromatic polyester resin, polybutadiene, 1,2-polybutadiene, polyisoprene, styrene / butadiene copolymer, butadiene / acrylonitrile copolymer, natural rubber, etc.), epoxy resin, diallyl phthalate prepolymer, silicone resin, silicone rubber, epichlorohydrin rubber, acrylic rubber, and PLA resin (polylactic acid) produced by polymerizing plant-derived monomers extracted from bio-raw materials. Other examples include neutralizing agents, antioxidants, UV absorbers, nucleating agents, lubricants, antistatic agents, antiblocking agents, processing aids, organic peroxides, colorants (inorganic pigments, organic pigments, pigment dispersants, etc.), foaming agents, foaming nucleating agents, plasticizers, flame retardants, crosslinking agents, crosslinking aids, brightness enhancers, antibacterial agents, light diffusing agents, and light stabilizers.

[0121] Examples of organic fillers include polyester, aromatic polyamide, cellulose, and vinylon.

[0122] <Ash Content> From the viewpoint of obtaining a molded article with low tear strength and a smooth surface, the propylene resin composition according to this embodiment has an ash content of 0.01% by mass or more and 25% by mass or less when heated at 600°C for 60 minutes, based on 100% by mass of the total mass of the propylene resin composition. The ash content is preferably 0.05% by mass or more, and more preferably 0.1% by mass or more. Furthermore, the ash content is preferably 22% by mass or less, and more preferably 20% by mass or less.

[0123] The amount of ash is determined by the following method. First, the crucible is heated in an electric furnace at 600°C for 60 minutes, then removed and cooled in a desiccator for 60 minutes before being weighed with a precision balance. 30 g of pellets are weighed into the crucible and heated in an electric furnace at 600°C for 60 minutes to completely ashify them. Next, the crucible is cooled in a desiccator for 1 hour, and the mass of the ash is measured to the nearest 0.01 mg using a precision balance, and the amount of ash (mass %) relative to the propylene resin composition is calculated.

[0124] In the propylene resin composition according to this embodiment, the ash content is thought to include, for example, the inorganic component mentioned above.

[0125] <Ash Filtration Residue Components> In this embodiment, from the viewpoint of obtaining a molded article with low tear strength and a smooth surface, the amount of ash filtration residue components obtained when the ash is filtered through a metal mesh (mesh opening 0.026 mm) is 0.003% by mass or more and 0.100% by mass or less, based on 100% by mass of the total mass of the propylene resin composition. From the viewpoint of obtaining a molded article with low tear strength, the amount of ash filtration residue components is preferably 0.005% by mass or more, and more preferably 0.007% by mass or more. Furthermore, from the viewpoint of obtaining a molded article with a smooth surface, the amount of ash filtration residue components is preferably 0.090% by mass or less, and more preferably 0.070% by mass or less.

[0126] The amount of ash filtration residue is determined by the following method. First, the mass of a metal mesh (manufactured by Sankyo Kanaami Seisakusho Co., Ltd.: twill weave 500 mesh, standard wire diameter 0.025 mmΦ as defined in JIS-G3555, mesh opening 0.026 mm, void ratio 26%) is measured to the nearest 0.01 mg using a precision balance. The total amount of ash obtained by the above method is ground in a mortar with a load of approximately 1000 g and rotated at a speed of approximately 140 revolutions per minute for 120 rotations. To confirm that it has been ground sufficiently, a solution prepared in the same way as the sample is filtered through a metal mesh (mesh opening 0.850 mm) and checked to see if any residue remains. Then, the solution is placed in ethanol adjusted to 1 g / 100 ml and diffused in an ultrasonic cleaner for 10 minutes to obtain a solution. The obtained solution is quickly filtered through the aforementioned metal mesh within 30 seconds before the ash coagulates, and then the metal mesh is thoroughly washed with approximately 50 ml of ethanol. Next, the obtained filtrate is filtered again through the aforementioned metal mesh, and then the metal mesh is thoroughly washed with approximately 50 mL of ethanol. After that, it is rinsed with approximately 10 mL of acetone. Next, the filtered metal mesh is vacuum dried at 50°C for 30 minutes, and the mass of the dried metal mesh is measured to the nearest 0.01 mg. The amount of ash filtration residue (mass%) relative to the pellet input amount (30 g) is then calculated using the following formula: Amount of ash filtration residue (mass%) = (Mass of metal mesh after filtration (g) - Mass of metal mesh before filtration (g)) / Input amount (g) × 100

[0127] In the propylene resin composition according to this embodiment, the ash filtration residue component is thought to include, for example, glass fibers.

[0128] In the propylene resin composition according to this embodiment, the ratio of the amount of ash filtration residue component to the amount of ash is preferably 0.00012 or more and 1 or less, more preferably 0.001 or more and 1 or less, from the viewpoint of obtaining a molded article with low tear strength and a smooth surface.

[0129] The melt flow rate (MFR, temperature 230°C, load 2.16 kg) of the propylene resin composition is preferably 1 g / 10 min to 100 g / 10 min, more preferably 12 g / 10 min to 70 g / 10 min, and even more preferably 15 g / 10 min to 40 g / 10 min. From the viewpoint of improving moldability, the MFR of the propylene resin composition is preferably 10 g / 10 min or more. From the viewpoint of improving the impact strength of the resulting molded article, the MFR of the propylene resin composition is preferably 100 g / 10 min or less.

[0130] The specific gravity of the propylene resin composition is preferably 1.30 or less, more preferably 1.20 or less, and even more preferably 1.10 or less. Furthermore, the specific gravity of the propylene resin composition is preferably 0.80 or more, more preferably 0.85 or more, and even more preferably 0.90 or more. The specific gravity is measured by the water displacement method, which is Method A described in JIS K7112.

[0131] The propylene resin composition according to this embodiment is obtained by melt-kneading a propylene polymer, an inorganic component, and, if necessary, an ethylene-α-olefin copolymer and other components.

[0132] The temperature during melting and kneading may be 180°C or higher, 180°C to 300°C, or 180°C to 250°C.

[0133] For melt mixing, a Banbury mixer, a single-screw extruder, a twin-screw co-rotating extruder, etc., can be used.

[0134] The order in which each raw material component is mixed is not particularly limited. For example, all components may be mixed together at once, or some components may be mixed first, and then the resulting mixture may be mixed with the other components.

[0135] The propylene resin composition according to this embodiment may include other optional steps. Optional steps include, for example, crushing, purification, and molding into pellet form. Purification steps include, for example, washing with water, aqueous and / or oily chemicals, microbial treatment, magnetic separation, and specific gravity separation. Molding steps are not particularly limited and include, for example, injection molding.

[0136] The shape of the propylene resin composition obtained in this manner is not particularly limited and may be in the form of strands, sheets, plates, or pellets. A pelletized resin composition can be produced, for example, by forming a stranded resin composition and then cutting it to an appropriate length.

[0137] From the viewpoint of improving the moldability of the propylene resin composition and the production stability when manufacturing molded articles, the shape of the propylene resin composition before molding is preferably in the form of pellets with a length of about 1 to 50 mm.

[0138] The propylene resin composition according to this embodiment comprises a propylene polymer and an inorganic component, and the amount of ash content when heated at 600°C for 60 minutes is 0.01% to 25% by mass per 100% by mass of the total mass of the propylene resin composition, and the amount of ash filtration residue when the ash content is filtered twice through a metal mesh (mesh opening 0.026 mm) is 0.003% to 0.100% by mass, thereby obtaining a molded article with relatively low tear strength and a relatively smooth surface. Furthermore, since the propylene resin composition according to this embodiment can produce a molded article with relatively good dismantling properties, the molded article can be suitably recycled.

[0139] <Molded Article> The molded article according to this embodiment includes the propylene resin composition described above. That is, the propylene resin composition described above can be used as a material for molding to form a molded article. Preferably, the propylene resin composition described above can be used as an injection molding material. An example of an injection molded article manufactured using the propylene resin composition as an injection molding material will be described below.

[0140] Injection-molded articles can be manufactured by injection molding. Examples of injection molding methods include general injection molding, injection foam molding, supercritical injection foam molding, ultra-high-speed injection molding, injection compression molding, gas-assisted injection molding, sandwich molding, sandwich foam molding, and insert / outsert molding. The shape of the injection-molded article is not particularly limited.

[0141] Injection-molded articles can be used, for example, in automotive materials, home appliance materials, containers, etc., and are preferably used in automotive interior and exterior applications. Examples of automotive interior and exterior parts include door trims, pillars, instrument panels, bumpers, airbag covers, etc.

[0142] The molded article according to this embodiment, by containing the above-mentioned propylene resin composition, has relatively low tear strength and a relatively smooth surface. Furthermore, the molded article according to this embodiment has relatively good disassembly properties and can be suitably recycled.

[0143] The present invention includes the following embodiments: [1] A propylene resin composition comprising a propylene polymer and an inorganic component, wherein the amount of ash when heated at 600°C for 60 minutes is 0.01% by mass or more and 25% by mass or less based on 100% by mass of the total mass of the propylene resin composition, the amount of ash filtration residue when the ash is filtered twice through a metal mesh (mesh opening 0.026 mm) is 0.003% by mass or more and 0.100% by mass or less, and the inorganic component comprises glass fibers, wherein the content of the glass fibers is 0.005% by mass or more and 0.100% by mass or less based on 100% by mass of the total mass of the propylene resin composition. [2] The propylene resin composition according to [1], wherein the content of the propylene polymer is 75.000% by mass or more and 99.995% by mass or less based on 100% by mass of the total mass of the propylene resin composition. [3] The propylene resin composition according to [1] or [2], wherein the ratio of the amount of ash filtration residue component to the amount of ash is 0.00012 or more and 1 or less. [4] The propylene resin composition according to any one of [1] to [3], comprising a heterophagic propylene polymerization material as the propylene polymer. [5] The propylene resin composition according to any one of [1] to [4], comprising a recycled heterophagic propylene polymerization material as the propylene polymer. [6] The propylene resin composition according to any one of [1] to [5], further comprising an ethylene-α-olefin copolymer. [7] The propylene resin composition according to [6], wherein the content of the ethylene-α-olefin copolymer is 1% by mass or more and 40% by mass or less based on 100% by mass of the total mass of the propylene resin composition. [8] The propylene resin composition according to [6] or [7], comprising a recycled ethylene-α-olefin copolymer as the ethylene-α-olefin copolymer. A molded article comprising the propylene resin composition described in any one of [9], [1], to [8].

[0144] The present invention will be described in more detail below with reference to examples. However, the present invention is not limited to these examples.

[0145] The following raw materials were used in the examples and comparative examples.

[0146] Component A: Propylene polymers were prepared as component A, namely (A-1) and (A-2) below.

[0147] (A-1) Heterophasic propylene polymerization material A heterophasic propylene polymerization material was produced by gas-phase polymerization in the presence of a polymerization catalyst obtained by the method described in Example 1 of Japanese Patent Application Publication No. 2004-182981. The physical properties of the obtained component A-1 are as follows.

[0148] Melt flow rate (MFR) (230°C, 2.16 kg load): 31.5 g / 10 min (a) Intrinsic viscosity of propylene homopolymer component (P portion): 1.00 dL / g (b) Intrinsic viscosity of propylene-ethylene copolymer component (EP portion): 5.0 dL / g Amount of propylene-ethylene copolymer component: 15.3% by mass Content of monomer units derived from ethylene: 40.8% by mass

[0149] (A-2) Heterophasic propylene polymerization material melt flow rate (MFR) (230°C, 2.16 kg load): 67.0 g / 10 min (a) Propylene homopolymer component (P portion) intrinsic viscosity: 0.86 dL / g (b) Propylene-ethylene copolymer component (EP portion) intrinsic viscosity: 5.4 dL / g Propylene-ethylene copolymer component amount: 12.5% ​​by mass Content of monomer units derived from ethylene: 38.7% by mass

[0150] Component B: Ethylene-α-olefin copolymer. The following ethylene-α-olefin copolymers (B-1) and (B-2) were prepared as component B.

[0151] (B-1) Ethylene-1-octene copolymer, Dow Chemical Company, "EG8180" MFR (temperature 190°C, load 2.16 kg): 0.5 g / 10 min Density: 0.863 g / cm³ ３

[0152] (B-2) Ethylene-1-octene copolymer, Dow Chemical Company "EG8100" MFR (temperature 190°C, load 2.16 kg): 1.0 g / 10 min Density: 0.870 g / cm³ ３

[0153] Component C: Inorganic component. The following inorganic components (C-1), (C-2), and (C-3) were prepared as component C.

[0154] (C-1) Talc Hayashi Chemical Co., Ltd. "MW UPN TT-H" Average particle size D50 [L] (laser diffraction method, 50% equivalent particle size): 4.90 μm

[0155] (C-2) Talc Hayashi Chemical Co., Ltd. "JR51-7" Average particle size D50 [L] (laser diffraction method, 50% equivalent particle size): 12.40 μm

[0156] (C-3) Glass fiber (chopped strand) Manufactured by Nippon Electric Glass Co., Ltd.: ESC03T-480H Diameter: 10.5 μm Fiber length: 3.0 mm

[0157] Component D: Other additives and other optional suitable components. The following components were used as component D. The total amount of component D is shown in Tables 1 to 3.

[0158] Calcium stearate (neutralizing agent) manufactured by Sakai Chemical Industry Co., Ltd. Caltech LT (neutralizing agent) manufactured by Suzuki Industries Co., Ltd. Sumitomo Chemical Co., Ltd. SumiLizer GA80 (antioxidant) Sonwon Co., Ltd. SONGNOX 6260 (antioxidant) BASF Inc. IRGAFOS 168 (antioxidant) BASF Inc. IRGANOX 1010 (antioxidant) Sumitomo Chemical Co., Ltd. SumiLizer TPM (antioxidant) Sumika Chemtex Inc. Sumisorb 400 (UV absorber) BASF Inc. Tinuvin 770DF (light stabilizer) Marubishi Oil & Chemical Industry Co., Ltd. Denon SL-12 (lubricant) NOF Corporation Alflow H-50P (lubricant)

[0159] <Method for measuring ash content> The crucible was heated in an electric furnace at 600°C for 60 minutes, then removed and cooled in a desiccator for 60 minutes before being weighed with a precision balance. 30 g of pellets were weighed into the crucible and heated in an electric furnace at 600°C for 60 minutes to completely ashify them. Next, the crucible was cooled in a desiccator for 1 hour, and the mass of the ash was measured to the nearest 0.01 mg using a precision balance, and the amount of ash (mass %) relative to the pellets was calculated.

[0160] <Method for measuring the amount of ash filtration residue> The mass of a metal mesh (manufactured by Sankyo Kanaami Seisakusho Co., Ltd.: twill weave 500 mesh, standard wire diameter 0.025 mmΦ as defined by JIS-G3555, mesh opening 0.026 mm, void ratio 26%) was measured to the nearest 0.01 mg using a precision balance. The total amount of ash obtained by the above method was ground in a mortar with a load of 1000 g and rotated at a speed of 140 rpm for 120 rotations. To confirm that it was sufficiently ground, a solution prepared in the same way as the sample was filtered through a metal mesh (mesh opening 0.850 mm) and it was confirmed that no residue remained. After that, the solution was placed in ethanol adjusted to 1 g / 100 ml and diffused in an ultrasonic cleaner for 10 minutes to obtain a solution. The obtained solution was quickly filtered through the aforementioned metal mesh within 30 seconds before the ash agglomerated, and then the metal mesh was thoroughly washed with approximately 50 mL of ethanol. Next, the obtained filtrate was filtered again through the aforementioned metal mesh, and then thoroughly washed with approximately 50 mL of ethanol. After that, it was rinsed with approximately 10 mL of acetone. Next, the filtered metal mesh was vacuum-dried at 50°C for 30 minutes, and the mass of the dried metal mesh was measured to the nearest 0.01 mg. The amount of ash filtration residue (mass%) relative to the pellet input amount (30 g) was calculated using the following formula: Amount of ash filtration residue (mass%) = (Mass of metal mesh after filtration (g) - Mass of metal mesh before filtration (g)) / Input amount (g) × 100

[0161] <Examples 1-11 and Comparative Examples 1-4> (Production of Propylene Resin Composition) Components A-D of the compositions shown in Tables 1-3 were uniformly pre-mixed in a Henschel mixer or tumbler. Then, the mixture was melt-kneaded in a Tanabe Plastics Co., Ltd. V40-NSIII type single-screw extruder (cylinder inner diameter 40.0 mm, screw outer diameter 39.5 mm, L / D = 28) under the conditions of cylinder temperature 200°C, screw rotation speed 100 rpm, and screen mesh 100 mesh to obtain a pelletized resin composition.

[0162] (Manufacturing of extruded articles for evaluation of tear strength and surface roughness) A pelletized propylene resin composition was extruded under the following conditions to produce extruded articles with a thickness of 50 μm for evaluation of tear strength and surface roughness. When holes were formed on the surface of the extruded article during manufacturing, it was considered to have poor processing stability (processing stability ×). Extrusion molding machine: Single-screw extruder VS20-14V type manufactured by Tanabe Plastics Co., Ltd. Cylinder inner diameter 20 mm, screw outer diameter 19.8 mm, L / D = 26 Cylinder temperature: 230℃ Screw rotation speed: 50 rpm Screen mesh: 100 mesh T-die: Width 100 mm, lip opening 0.5 mm Chill roll cooling temperature: 30℃ Winding speed: 5 m / min

[0163] (Evaluation of tear strength) Test specimens were prepared by punching out the extruded material obtained by the method described above using a punching die for JIS K6252 angle-type test specimens without cuts for tear testing. The punching direction was such that the longer side was perpendicular to the extrusion direction. The tear strength of the prepared test specimens was evaluated under the following conditions: Tensile testing machine: Tensilon single-column type material testing machine (STB-1225L) manufactured by A&D Co., Ltd. Chuck distance: 75 mm Tensile speed: 200 mm / min

[0164] (Evaluation of surface roughness) The surface of the extruded article obtained by the method described above was evaluated for arithmetic mean roughness (Ra) as defined in JIS-B0601:2001 under the following conditions: Measuring instrument: Surfcom 480A manufactured by Tokyo Seimitsu Co., Ltd. Probe tip shape: Conical, 60° Probe tip radius: 2 μm Measuring force: 0.75 mN Measuring speed: 0.3 mm / sec Cutoff value: 0.8 mm Evaluation length: 5 mm

[0165]

[0166]

[0167]

[0168] As can be seen from the results in Tables 1 to 3, the propylene resin compositions of each embodiment that satisfy all the constituent requirements of the present invention can produce molded articles with relatively low tear strength and relatively smooth surfaces.

Claims

1. A propylene resin composition comprising a propylene polymer and an inorganic component, wherein the amount of ash content when heated at 600°C for 60 minutes is 0.01% by mass or more and 25% by mass or less, based on 100% by mass of the total mass of the propylene resin composition, the amount of ash filtration residue when the ash content is filtered twice through a metal mesh (mesh opening 0.026 mm) is 0.003% by mass or more and 0.100% by mass or less, and the inorganic component includes glass fibers, wherein the content of the glass fibers is 0.005% by mass or more and 0.100% by mass or less, based on 100% by mass of the total mass of the propylene resin composition.

2. The propylene resin composition according to claim 1, wherein the content of the propylene polymer is 75.000% by mass or more and 99.995% by mass or less, based on 100% by mass of the total mass of the propylene resin composition.

3. The propylene resin composition according to claim 1, wherein the ratio of the amount of ash filtration residue component to the amount of ash is 0.00012 or more and 1 or less.

4. The propylene resin composition according to claim 1, comprising a heterophagic propylene polymerization material as the propylene polymer.

5. The propylene resin composition according to claim 1, comprising a recycled heterophagic propylene polymerization material as the propylene polymer.

6. The propylene resin composition according to claim 1, further comprising an ethylene-α-olefin copolymer.

7. The propylene resin composition according to claim 6, wherein the content of the ethylene-α-olefin copolymer is 1% by mass or more and 40% by mass or less based on 100% by mass of the total mass of the propylene resin composition.

8. The propylene resin composition according to claim 6, wherein the ethylene-α-olefin copolymer comprises a recycled ethylene-α-olefin copolymer.

9. A molded article comprising the propylene resin composition according to any one of claims 1 to 8.

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