Vehicle wiring harness connector

Abstract

To provide a connector for a vehicular wire harness that achieves both of light weight and rigidity (high flexural modulus).SOLUTION: A connector for vehicular wire harness 10 comprises a propylene resin composition comprising a propylene polymer with a weight average molecular weight of 500,000-1,000,000 in terms of polystyrene as calculated by GPC, and a molecular weight distribution (weight average molecular weight / number average molecular weight) of 6-10. The connector comprises at least one insertion part 10a, and at least one lance part 12 provided to project from a wall surface defining the insertion part. The lance part has a thickness of 1 mm or less.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a connector for a vehicle wire harness and a propylene-based resin composition. [Background technology]

[0002] Molded articles of propylene-based resin compositions are widely used in various fields where weight reduction is required, such as vehicle parts and machine parts.

[0003] In recent years, the electrification of vehicles has been promoted, for example, from the viewpoint of reducing carbon dioxide emissions. In addition, the addition of functions and electronics to improve the safety, comfort, and driving performance of automobiles has also progressed.

[0004] Under these circumstances, the importance of wire harnesses, which transmit power from batteries and signals from information and communication devices, is increasing, and there is a demand for more stable transmission of power and signals.In addition, the number of wire harness connectors installed in each vehicle is also increasing.

[0005] For example, Patent Document 1 below discloses a connector for automobiles that contains polybutylene terephthalate resin and polyolefin resin. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Publication No. 6-295761 Summary of the Invention [Problem to be solved by the invention]

[0007] For example, from the viewpoint of reducing carbon dioxide emissions from automobiles and improving fuel efficiency, further weight reduction of wire harness connectors is required, and therefore, the development of vehicle wire harness connectors containing propylene polymers as the main component is desired, while the vehicle wire harness connectors are required to have terminals inserted into the connector that fit firmly into the connector. In other words, vehicle wire harness connectors are required to achieve both weight reduction and rigidity (high flexural modulus). [Means for solving the problem]

[0008] The present inventors have conducted extensive research to solve the above problems, and have found that the above problems can be solved by using a specific component, thereby completing the present invention.

[0009] That is, the present invention provides the following [1] to [8]. [1] A propylene-based resin composition containing a propylene-based polymer having a weight-average molecular weight of 500,000 to 1,000,000 in terms of polystyrene, determined by a GPC method, and a molecular weight distribution (weight-average molecular weight / number-average molecular weight) of 6 to 10, A connector for a vehicle wire harness having one or more insertion portions and one or more lance portions provided so as to protrude from a wall surface defining the insertion portions, wherein the thickness of the lance portions is 1 mm or less. [2] The melt flow rate of the propylene polymer measured under conditions of a temperature of 230°C and a load of 2.16 kgf is 0.1 to 15 g / 10 min; The connector for a vehicle wire harness according to [1], wherein the propylene polymer has an intrinsic viscosity of 1.5 dL / g or more. [3] The connector for a vehicle wire harness according to [1] or [2], wherein the propylene-based resin composition further contains a nucleating agent and a hydrazide compound represented by the following formula (1): [ka] (In the formula (1), R1 and R2 each independently represent an alkyl group having 1 to 8 carbon atoms.) [4] The connector for a vehicle wire harness according to [3], wherein in the formula (1), R1 and R2 are tert-butyl groups. [5] The connector for a vehicle wire harness according to [3] or [4], wherein the nucleating agent contains a compound represented by the following formula (C-1) or a compound represented by the following formula (C-2). [ka] [6] The propylene-based polymer comprises a first propylene polymer component and a second propylene polymer component; the first propylene polymer component has an intrinsic viscosity of 5 to 8 dL / g; The connector for a vehicle wire harness according to any one of [1] to [5], wherein the second propylene polymer component has an intrinsic viscosity of 0.5 to 2 dL / g. [7] The proportion of the first propylene polymer component in the entire propylene-based polymer is 10% by mass or more and 20% by mass or less, The connector for a vehicle wire harness according to [6], wherein the second propylene polymer component accounts for 80% by mass or more and 90% by mass or less of the entire propylene-based polymer. [8] A propylene polymer having a melt flow rate of 0.1 to 15 g / 10 min measured under conditions of a temperature of 230 ° C and a load of 2.16 kgf and an intrinsic viscosity of 1.5 dL / g or more; A nucleating agent; A hydrazide compound represented by the following formula (1): A propylene-based resin composition comprising: [ka] (In the formula (1), R1 and R2 each independently represent an alkyl group having 1 to 8 carbon atoms.) [Effects of the Invention]

[0010] According to the present invention, it is possible to provide a connector for a vehicle wire harness, which contains a propylene-based polymer (propylene-based resin composition) that can achieve both weight reduction and rigidity (high flexural modulus). [Brief explanation of the drawings]

[0011] [Figure 1] FIG. 1 is a diagram illustrating a configuration example of a connector of a vehicle wire harness. [Figure 2] FIG. 2 is a diagram schematically showing a cut end surface of the connector of the vehicle wire harness taken along the dashed line AA shown in FIG. DETAILED DESCRIPTION OF THE INVENTION

[0012] Hereinafter, embodiments of the present invention will be described in detail. The present invention is not limited to the specific embodiments shown below. Note that the drawings merely show the shapes, sizes, and arrangements of components in a schematic manner to enable understanding of the invention, and each component can be modified as appropriate within the scope of the gist of the present invention.

[0013] 1. Explanation of terms Before describing the embodiments of the present invention, commonly used terms will first be explained.

[0014] In this specification, the term "monomer unit" refers to a structural unit (residue) derived from a monomer contained in a polymer obtained by polymerizing a monomer.

[0015] As used herein, "α-olefin" refers to an olefin containing a carbon atom chain of three or more carbon atoms having a terminal (α-position) carbon-carbon double bond.

[0016] In this specification, the "intrinsic viscosity (unit: dL / g)" is a value measured at a temperature of 135°C using tetralin as a solvent by the following method. Specifically, the intrinsic viscosity can be determined by the "extrapolation method" in which the reduced viscosity is measured at a plurality of concentrations using an Ubbelohde viscometer, the reduced viscosity is plotted against the concentration, and the concentration is extrapolated to zero. More specifically, the intrinsic viscosity can be determined by the method described on page 491 of "Polymer Solutions, Polymer Experiments 11" (published by Kyoritsu Shuppan Co., Ltd. in 1982), in which the reduced viscosity is measured at three 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 concentration is extrapolated to zero.

[0017] In this specification, "melt flow rate (MFR)" means "melt mass flow rate" and is the melt flow rate measured in accordance with JIS K7210-1:2014 and K7210-2:2014 under conditions of a temperature of 230°C and a load of 2.16 kgf.

[0018] In this specification, unless otherwise specified, "%" means "% by mass" and "parts" means "parts by mass".

[0019] 2. Propylene-based resin composition The propylene-based resin composition according to an embodiment of the present invention contains a propylene-based polymer having a weight average molecular weight of 500,000 to 1,000,000 in terms of polystyrene, determined by a GPC method, and a molecular weight distribution (weight average molecular weight / number average molecular weight) of 6 to 10.

[0020] Components that may be contained in the propylene-based resin composition of this embodiment will be described below.

[0021] (1) Component (A) Propylene-Based Polymer A propylene-based polymer is a polymer containing propylene units in an amount of more than 50% by mass relative to all constituent units (100% by mass). The propylene units in a propylene-based polymer are usually 100% by mass or less.

[0022] Examples of propylene-based polymers include propylene homopolymers and copolymers of propylene with other monomers copolymerizable therewith. The copolymers may be random copolymers or block copolymers.

[0023] Examples of other monomers copolymerizable with propylene include olefins other than propylene (eg, ethylene, olefins having 4 or more carbon atoms).

[0024] The olefin having 4 or more carbon atoms may be a linear olefin or a branched olefin. The olefin having 4 or more carbon atoms may be an olefin having a cyclic structure, such as an α-olefin having a cyclic structure, such as vinylcyclopropane or vinylcyclobutane.

[0025] Examples of olefins other than propylene that can be copolymerized with propylene include α-olefins other than propylene (e.g., ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-octene, and 1-decene). The olefins other than propylene that can be copolymerized with propylene are preferably ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-octene, and 1-decene, and more preferably ethylene, propylene, 1-butene, 1-hexene, and 1-octene.

[0026] The propylene resin composition of the present embodiment may contain two or more kinds of propylene polymers as the propylene polymer (A).

[0027] The propylene-based resin composition of the present embodiment may contain, as the component (A) propylene-based polymer, a component (A-1) propylene homopolymer in which only one propylene monomer is polymerized, or a propylene-based polymer in which two or more monomers are polymerized in any combination at any ratio.

[0028] Examples of component (A) propylene-based polymers include component (A-1) propylene homopolymers and random copolymers of propylene with other monomers copolymerizable therewith (hereinafter also referred to as propylene-based random copolymers).

[0029] Examples of combinations of two or more propylene polymers when two or more propylene polymers of component (A) are contained include a combination of two or more propylene homopolymers differing in weight average molecular weight, etc., and a combination of polymer (I) and polymer (II) shown below.

[0030] The propylene resin composition of the present embodiment may contain, as the propylene polymer component (A), a heterophasic propylene polymer material component (A-2).

[0031] Here, the component (A-2) heterophasic propylene polymer material means a material containing two or more types of propylene polymers, in which the two or more types of propylene polymers are not compatible with each other and form separate phases.

[0032] Examples of the component (A-2) heterophasic propylene polymer material include a combination of the following polymer (I) and polymer (II).

[0033] Here, the polymer (I) is a polymer having propylene units in an amount of more than 80 mass % and 100 mass % or less based on the amount of all constituent units.

[0034] The polymer (II) is a copolymer of propylene units and at least one monomer unit selected from the group consisting of ethylene units and α-olefin units having 4 or more carbon atoms. The polymer (II) is preferably a polymer having propylene units in an amount of more than 0% by mass and not more than 90% by mass, more preferably more than 0% by mass and not more than 80% by mass, based on the amount of all constituent units.

[0035] Polymer (I) may be a propylene homopolymer or a copolymer of propylene and another monomer. Polymer (I) and polymer (II) may each consist of only one type of polymer or may contain two or more types of polymers.

[0036] From the viewpoint of improving the rigidity and impact resistance of a molded article obtained by molding the propylene-based resin composition, the propylene-based polymer preferably contains one or more selected from the group consisting of propylene homopolymers and heterophasic propylene polymer materials.

[0037] The propylene polymer is used from the viewpoint of improving the rigidity of a molded article obtained by molding the propylene resin composition. 13 The isotactic pentad fraction (also called the [mmmm] fraction) measured by C-NMR is preferably 0.97 or more, more preferably 0.98 or more. The closer the isotactic pentad fraction of a propylene-based polymer is to 1, the higher the stereoregularity of the molecular structure of the propylene-based polymer and the higher the crystallinity of the propylene-based polymer. When the propylene-based polymer is a copolymer, the isotactic pentad fraction can be measured for the chain of propylene units in the copolymer.

[0038] From the viewpoint of improving the processability in molding of the propylene resin composition, the component (A) propylene polymer preferably has a melt flow rate (MFR) measured under conditions of a temperature of 230°C and a load of 2.16 kgf of 0.1 g / 10 min or more, more preferably 3 g / 10 min or more, preferably 500 g / 10 min or less, more preferably 100 g / 10 min or less, even more preferably 15 g / 10 min, and preferably 0.1 g / 10 min to 15 g / 10 min.

[0039] The component (A) propylene polymer can be produced, for example, by the following polymerization method using a polymerization catalyst.

[0040] Examples of polymerization catalysts include Ziegler-type catalyst systems; Ziegler-Natta-type catalyst systems; catalyst systems containing a Group 4 transition metal compound with a cyclopentadienyl ring and an alkylaluminoxane; catalyst systems containing a Group 4 transition metal compound with a cyclopentadienyl ring, a compound that reacts with the metal to form an ionic complex, and an organoaluminum compound; and catalyst systems in which catalytic components (e.g., a Group 4 transition metal compound with a cyclopentadienyl ring, a compound that forms an ionic complex, or an organoaluminum compound) are supported and modified on inorganic particles (e.g., silica, clay minerals, etc.). Prepolymerization catalysts prepared by prepolymerizing monomers such as ethylene or α-olefins in the presence of such catalyst systems may also be used. Examples of Ziegler-Natta-type catalyst systems include catalyst systems that use a titanium-containing solid transition metal component in combination with an organometallic component.

[0041] Examples of such catalyst systems include those described in JP-A Nos. 61-218606, 5-194685, 7-216017, 9-316147, 10-212319, and 2004-182981.

[0042] Examples of polymerization methods include bulk polymerization, solution polymerization, and gas-phase polymerization. Here, bulk polymerization refers to a method in which polymerization is carried out using an olefin that is liquid 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, or octane. Gas-phase polymerization refers to a method in which gaseous monomers are used as a medium and the gaseous monomers are polymerized in that medium.

[0043] Examples of the polymerization method include a batch system, a continuous system, and a combination thereof. The polymerization method may be a multi-stage system using a plurality of polymerization reactors connected in series.

[0044] Various conditions in the polymerization method (polymerization temperature, polymerization pressure, monomer concentration, catalyst input amount, polymerization time, etc.) can be appropriately determined depending on the desired propylene-based polymer.

[0045] In the production of a propylene polymer, the resulting propylene polymer may be maintained at a temperature at which impurities such as residual solvent and oligomers can volatilize but which is lower than the temperature at which the propylene polymer melts, thereby removing residual solvent contained in the resulting propylene polymer and ultralow molecular weight oligomers by-produced during the production. Examples of methods for removing impurities such as residual solvent and oligomers include the methods described in JP-A-55-75410 and JP-A-2565753.

[0046] From the viewpoint of improving the fluidity of the propylene-based resin composition when melted and the toughness of a molded article obtained by molding the propylene-based resin composition, the component (A-1) propylene homopolymer preferably has an intrinsic viscosity [η] of 0.1 to 5 dL / g, more preferably 0.5 to 5 dL / g, and even more preferably 0.7 to 4 dL / g.

[0047] Furthermore, from the viewpoint of improving the fluidity of the propylene-based resin composition when melted and the toughness of a molded article containing the resin composition, the propylene homopolymer preferably has a molecular weight distribution Mw / Mn of 2 or more and less than 10, more preferably 3 to 8, and even more preferably 3 to 7. Here, Mw represents the weight-average molecular weight, and Mn represents the number-average molecular weight. The molecular weight distribution can be measured by gel permeation chromatography (GPC).

[0048] Examples of propylene-based random copolymers include a random copolymer containing propylene units and ethylene units (hereinafter also referred to as random polymer (1)); a random copolymer containing propylene units and α-olefin units having 4 or more carbon atoms (hereinafter also referred to as random polymer (2)); and a random copolymer containing propylene units, ethylene units, and α-olefin units having 4 or more carbon atoms (hereinafter also referred to as random polymer (3)).

[0049] The α-olefin having 4 or more carbon atoms that can constitute the propylene-based random copolymer is preferably an α-olefin having 4 to 10 carbon atoms. Examples of the α-olefin having 4 to 10 carbon atoms include 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-octene, and 1-decene, and 1-butene, 1-hexene, and 1-octene are preferred.

[0050] Examples of the random copolymer (2) include propylene-1-butene random copolymer, propylene-1-hexene random copolymer, propylene-1-octene random copolymer, and propylene-1-decene random copolymer.

[0051] Examples of the random copolymer (3) include propylene-ethylene-1-butene copolymer, propylene-ethylene-1-hexene copolymer, propylene-ethylene-1-octene copolymer, and propylene-ethylene-1-decene copolymer.

[0052] The content of ethylene units in the random copolymer (1) is preferably 0.1 to 40% by mass.

[0053] The content of α-olefin units having 4 or more carbon atoms in the random copolymer (2) is preferably 0.1 to 40 mass %, more preferably 0.1 to 30 mass %, and even more preferably 2 to 15 mass %.

[0054] The total content of ethylene units and α-olefin units having 4 or more carbon atoms in the random copolymer (3) is preferably 0.1 to 40 mass %, more preferably 0.1 to 30 mass %, and even more preferably 2 to 15 mass %.

[0055] The content of propylene units in each of these random copolymers (1) to (3) is preferably 60 to 99.9% by mass.

[0056] As already explained, polymer (I) in the component (A-2) heterophasic propylene polymer material is a polymer containing propylene units in an amount of more than 80% by mass and not more than 100% by mass based on the amount of all constituent units. The total content of monomer units other than propylene units in polymer (I), when the mass of polymer (I) is taken as 100% by mass, is usually 0% by mass or more and less than 20% by mass, and may be 0% by mass or more, or may be 0.01% by mass or more.

[0057] Examples of monomer units other than propylene units that may be contained in the polymer (I) include ethylene units and α-olefin units having 4 or more carbon atoms.

[0058] The α-olefin having 4 or more carbon atoms that can constitute the polymer (I) is preferably an α-olefin having 4 to 10 carbon atoms, more preferably 1-butene, 1-hexene, and 1-octene, and even more preferably 1-butene.

[0059] Examples of polymer (I) include propylene homopolymer, propylene-ethylene copolymer, propylene-1-butene copolymer, propylene-1-hexene copolymer, propylene-1-octene copolymer, propylene-ethylene-1-butene copolymer, propylene-ethylene-1-hexene copolymer, and propylene-ethylene-1-octene copolymer.

[0060] Among these, as the polymer (I), propylene homopolymer, propylene-ethylene copolymer, propylene-1-butene copolymer, and propylene-ethylene-1-butene copolymer are preferred, and propylene homopolymer is more preferred from the viewpoint of improving the rigidity of a molded article obtained by molding the propylene-based resin composition.

[0061] As already explained, the polymer (II) is a copolymer of propylene units and at least one monomer unit selected from the group consisting of ethylene units and α-olefin units having 4 or more carbon atoms.

[0062] The total content of ethylene units and α-olefin units having 4 or more carbon atoms in polymer (II) is preferably 20 to 80 mass%, and more preferably 20 to 60 mass%, when the mass of polymer (II) is taken as 100 mass%.

[0063] The α-olefin having 4 or more carbon atoms that can constitute polymer (II) is preferably an α-olefin having 4 to 10 carbon atoms, and examples thereof include the same as the examples of α-olefins that can constitute polymer (I) already described.

[0064] 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. Polymer (II) is preferably propylene-ethylene copolymer, propylene-1-butene copolymer, or propylene-ethylene-1-butene copolymer, more preferably propylene-ethylene copolymer.

[0065] The content of polymer (II) in the component (A-2) heterophasic propylene polymer material is preferably 1 to 50 mass%, more preferably 1 to 45 mass%, even more preferably 5 to 40 mass%, and particularly preferably 8 to 32 mass%, when the total mass of polymer (I) and polymer (II) is 100 mass%.

[0066] Examples of the heterophasic propylene polymer material for component (A-2) include a combination of a propylene homopolymer and a (propylene-ethylene) copolymer, a combination of a propylene homopolymer and a (propylene-ethylene-1-butene) copolymer, a combination of a propylene homopolymer and a (propylene-ethylene-1-hexene) copolymer, a combination of a propylene homopolymer and a (propylene-ethylene-1-octene) copolymer, a combination of a propylene homopolymer and a (propylene-1-butene) copolymer, a combination of a propylene homopolymer and a (propylene-1-hexene) copolymer, a combination of a propylene homopolymer and a (propylene-1-octene) copolymer, and a combination of a propylene homopolymer and a (propylene-1-decene) copolymer.

[0067] The heterophasic propylene polymer material may also be a combination in which polymer (I) is a polymer containing propylene units and monomer units other than propylene units. Listing the type of polymer (I) first and the type of polymer (II) second, specific examples of such heterophasic propylene polymer materials include a combination of a (propylene-ethylene) copolymer and a (propylene-ethylene) copolymer, a combination of a (propylene-ethylene) copolymer and a (propylene-ethylene-1-butene) copolymer, a combination of a (propylene-ethylene) copolymer and a (propylene-ethylene-1-hexene) copolymer, and a combination of a (propylene-ethylene) copolymer and a (propylene-ethylene-1-hexene) copolymer. a combination of a (propylene-ethylene) copolymer and a (propylene-ethylene-1-decene) copolymer; a combination of a (propylene-ethylene) copolymer and a (propylene-1-butene) copolymer; a combination of a (propylene-ethylene) copolymer and a (propylene-1-hexene) copolymer; a combination of a (propylene-ethylene) copolymer and a (propylene-1-octene) copolymer; a combination of a (propylene-ethylene) copolymer and a (propylene-1-decene) copolymer; combinations of (propylene-1-butene) copolymers and (propylene-ethylene) copolymers; combinations of (propylene-1-butene) copolymers and (propylene-ethylene-1-butene) copolymers; combinations of (propylene-1-butene) copolymers and (propylene-ethylene-1-hexene) copolymers; combinations of (propylene-1-butene) copolymers and (propylene-ethylene-1-octene) copolymers; combinations of (propylene-1-butene) copolymers and (propylene-ethylene-1-decene) copolymers combinations of (propylene-1-butene) copolymers and (propylene-1-butene) copolymers, combinations of (propylene-1-butene) copolymers and (propylene-1-hexene) copolymers, combinations of (propylene-1-butene) copolymers and (propylene-1-octene) copolymers, combinations of (propylene-1-butene) copolymers and (propylene-1-decene) copolymers, combinations of (propylene-1-hexene) copolymers and (propylene-1-hexene) copolymers,Examples of the copolymer include a combination of a (propylene-1-hexene) copolymer and a (propylene-1-octene) copolymer, a combination of a (propylene-1-hexene) copolymer and a (propylene-1-decene) copolymer, a combination of a (propylene-1-octene) copolymer and a (propylene-1-octene) copolymer, and a combination of a (propylene-1-octene) copolymer and a (propylene-1-decene) copolymer.

[0068] Preferred examples of the heterophasic propylene polymer material (Component (A-2)) that can be contained in the propylene-based resin composition of this embodiment include a combination of a propylene homopolymer and a (propylene-ethylene) copolymer, a combination of a propylene homopolymer and a (propylene-ethylene-1-butene) copolymer, a combination of a (propylene-ethylene) copolymer and a (propylene-ethylene) copolymer, a combination of a (propylene-ethylene) copolymer and a (propylene-ethylene-1-butene) copolymer, and a combination of a (propylene-1-butene) copolymer and a (propylene-1-butene) copolymer, with a combination of a propylene homopolymer and a (propylene-ethylene) copolymer being more preferred.

[0069] The heterophasic propylene polymer material can be produced by multi-stage polymerization including a first polymerization step of producing polymer (I) and a second polymerization step of producing polymer (II) in the presence of polymer (I) produced in the first step. The polymerization can be carried out using the catalyst system exemplified above as a catalyst usable for producing the propylene polymer.

[0070] The intrinsic viscosity of the propylene polymer (A) of the present embodiment is usually less than 3 dL / g, 1 dL / g or more, preferably 1.5 dL / g or more, more preferably 1 dL / g or more and less than 3 dL / g, and even more preferably 1.5 dL / g or more and less than 3 dL / g, from the viewpoints of improving the fluidity and processability of the propylene resin composition, suppressing coloration of the molded product, and achieving both rigidity and copper damage prevention performance.

[0071] In this embodiment, the propylene polymer (A) typically has a weight average molecular weight in terms of polystyrene of 100,000 to 1,000,000, and preferably 500,000 to 1,000,000, from the viewpoint of improving the appearance and elongation properties of the molded article.

[0072] The component (A) propylene polymer generally has a molecular weight distribution (Mw / Mn) of 10 or less, preferably 3-10, from the viewpoint of moldability and mechanical properties.

[0073] Here, Mw represents the weight-average molecular weight, and Mn represents the number-average molecular weight. The weight-average molecular weight, number-average molecular weight, and molecular weight distribution can be measured by gel permeation chromatography (GPC) and calculated in terms of polystyrene.

[0074] When the propylene polymer is a polymer material composed of polymer (I) and polymer (II) formed by multistage polymerization, a part of polymer (I) prepared in the first polymerization stage is extracted from the polymerization reactor to determine its intrinsic viscosity, and the intrinsic viscosity (hereinafter referred to as ([η]Total)) of the propylene polymer finally obtained by the multistage polymerization is determined, and the intrinsic viscosity of the polymer formed in the second polymerization stage can be calculated using these intrinsic viscosity values ​​and the content of each polymer.

[0075] Furthermore, when a polymer material consisting of polymer (I) and polymer (II) is a material produced by a method in which polymer (I) is obtained in an earlier polymerization step and polymer (II) is obtained in a later polymerization step, the procedures for measuring and calculating the contents and limiting viscosities ([η]Total, [η]I, [η]II) of polymer (I) and polymer (II) are as follows:

[0076] The intrinsic viscosity [η]II of polymer (II) can be calculated from the intrinsic viscosity ([η]I) of polymer (I) obtained in the previous polymerization step, the intrinsic viscosity ([η]Total) of the final polymer after the subsequent polymerization step (i.e., a polymer consisting of polymer (I) and polymer (II)) measured by the above-mentioned method, and the content of polymer (II) contained in the final polymer, using the following formula.

[0077] [η]II=([η]Total-[η]I×XI) / XII [η]Total: Intrinsic viscosity of the final polymer (unit: dL / g) [η]I: Intrinsic viscosity of polymer (I) (unit: dL / g) XI: Mass ratio of polymer (I) to final polymer XII: Mass ratio of polymer (II) to final polymer XI and XII can be determined from the mass balance during polymerization.

[0078] The intrinsic viscosity (hereinafter referred to as [η]I) of the polymer (I) is preferably 1 to 10 dL / g, more preferably 2 to 10 dL / g, and even more preferably 5 to 8 dL / g.

[0079] The intrinsic viscosity (hereinafter referred to as [η]II) of the polymer (II) is preferably 0.1 to 5 dL / g, more preferably 0.5 to 5 dL / g, and even more preferably 0.5 to 2 dL / g.

[0080] The ratio of [η]II to [η]I ([η]II / [η]I) is preferably 0.01 to 5, more preferably 0.05 to 2.5, and even more preferably 0.06 to 0.4.

[0081] The mass ratio XII of polymer (II) to the final polymer may be calculated from the following formula using the heat of crystalline fusion of polymer (I) and the final polymer, respectively. XII=1-(ΔHf)T / (ΔHf)P (ΔHf)T: Heat of fusion of the final polymer (polymer (I) and polymer (II)) (unit: cal / g) (ΔHf)P: Heat of fusion of polymer (I) (unit: cal / g)

[0082] The molecular weight distribution (Mw / Mn) of the polymer (I) measured by GPC is preferably 1 or more and less than 10, more preferably 2 or more and less than 7, and even more preferably 3 or more and less than 5.

[0083] The content of the propylene polymer in the propylene resin composition of the present embodiment is preferably 50% by mass or more, more preferably 80% by mass or more, and even more preferably 90% by mass or more, when the total amount of the propylene resin composition is 100% by mass.

[0084] Here, particularly preferred examples of the propylene polymer (component (A)) according to this embodiment will be described.

[0085] A particularly suitable propylene polymer component (A) in this embodiment is composed of a first propylene polymer component (a) and a second propylene polymer component (b) having a different molecular weight from the first propylene polymer component (a).

[0086] Here, the first propylene polymer component (a) is preferably an isotactic propylene polymer. As the first propylene polymer component (a), a propylene homopolymer or a copolymer of propylene with ethylene or an α-olefin having 4 to 12 carbon atoms to such an extent that crystallinity is not lost is particularly preferred. Examples of the α-olefin include 1-butene, 4-methylpentene-1, 1-octene, and 1-hexene.

[0087] The content of monomers other than propylene is preferably 10% by mass or less when the monomer is ethylene, and is preferably 30% by mass or less when the monomer is an α-olefin.

[0088] The first propylene polymer component (a) is preferably a crystalline propylene copolymer component selected from a propylene homopolymer, a random copolymer of propylene and 10% by mass or less of ethylene, a random copolymer of propylene and 30% by mass or less of an α-olefin having 4 to 12 carbon atoms, or a ternary random copolymer of propylene, 10% by mass or less of ethylene, and 30% by mass or less of an α-olefin having 4 to 12 carbon atoms, with 1-butene being a more preferred α-olefin. A particularly preferred first propylene polymer component (a) in terms of flexibility is a copolymer containing 1% to 10% by mass of ethylene.

[0089] The intrinsic viscosity of the first propylene polymer component (a) is preferably 1 to 10 dL / g, more preferably 2 to 10 dL / g, and even more preferably 5 to 8 dL / g, from the viewpoint of the melt strength of the propylene polymer.

[0090] The proportion of the first propylene polymer component (a) in the entire component (A) propylene polymer is usually 0.05% by mass or more and less than 25% by mass, preferably 0.3% by mass or more and less than 20% by mass, and more preferably 10% by mass or more and 20% by mass or less, in order to ensure melt strength, fluidity, and elongation properties.

[0091] From the viewpoint of improving the melt strength, fluidity during melting, and rigidity, the amount of the first propylene polymer component (a) preferably satisfies the following formula: When the amount of the first propylene polymer component (a) satisfies the following formula, the melt strength, fluidity during melting, and rigidity of the molded article can be effectively improved. Content (mass%) of first propylene polymer component (a) ≧ 400 × EXP (−0.6 × intrinsic viscosity (dL / g) of first propylene polymer component (a))

[0092] In the formula (1), EXP(X) represents eX, where e represents the base of the natural logarithm.

[0093] In particular, from the viewpoint of the flowability of the propylene-based resin composition, it is preferable that the content of the first propylene polymer component (a) is as small as possible, provided that the requirements defined by the above formula are satisfied.

[0094] The second propylene polymer component (b) in this embodiment is preferably a propylene polymer obtained by further continuous preparation following the preparation of the first propylene polymer component (a).

[0095] That is, in the propylene polymer component (A) of this embodiment, simply blending a crystalline propylene polymer having an intrinsic viscosity of 5 dL / g or more with a propylene polymer having an intrinsic viscosity of less than 3 dL / g may not exhibit effects related to melt strength, etc., or the effects may be insufficient. Therefore, the second propylene polymer component (b) is preferably prepared by first preparing the first propylene polymer component (a) by polymerizing a propylene-based monomer in the presence of a stereoregular olefin polymerization catalyst, such as a Ziegler-Natta catalyst, and subsequently polymerizing a propylene-based monomer in a different polymerization reaction vessel in the presence of the stereoregular olefin polymerization catalyst and the prepared first propylene polymer component (a).

[0096] The proportion of the second propylene polymer component (b) in the entire propylene polymer of component (A) is usually 75% by mass or more and less than 99.95% by mass, preferably 75% by mass or more and less than 99.7% by mass, and more preferably 80% by mass or more and 90% by mass or less, from the viewpoint of ensuring melt strength, fluidity, and elongation properties.

[0097] The intrinsic viscosity of the second propylene polymer component (b) is preferably 0.1 to 5 dL / g, more preferably 0.5 to 5 dL / g, and even more preferably 0.5 to 2 dL / g, from the viewpoint of improving the overall intrinsic viscosity, flowability, processability, and miscibility of the propylene polymer component (A).

[0098] The intrinsic viscosity [η]b of the second propylene polymer component (b) can be calculated by the following formula.

[0099] [η]b=([η]T×100-[η]a×Wa) / Wb [η]T: Intrinsic viscosity of the entire propylene polymer [η]a: intrinsic viscosity of the first propylene polymer component (a) Wa: Content (mass%) of the first propylene polymer component (a) Wb: Content (mass%) of the second propylene polymer component (b)

[0100] As the second propylene polymer component (b), an isotactic propylene polymer satisfying the above conditions is preferably used. Among these, propylene homopolymers, crystalline copolymers of propylene with ethylene and an α-olefin, and polymers in which an amorphous ethylene-α-olefin copolymer is dispersed in a crystalline propylene polymer are preferred. A particularly preferred second propylene polymer component (b) is a propylene homopolymer. To ensure crystallinity, examples of the second propylene polymer component (b) include a random copolymer of propylene and 10% by mass or less of ethylene, a random copolymer of propylene and 30% by mass or less of an α-olefin having 4 to 12 carbon atoms, and a ternary random copolymer of propylene, 10% by mass or less of ethylene, and 30% by mass or less of an α-olefin having 4 to 12 carbon atoms. An even more preferred α-olefin is, for example, 1-butene.

[0101] In this embodiment, the component (A) propylene polymer can be prepared using a stereoregular olefin polymerization catalyst. A preferred stereoregular olefin polymerization catalyst is one containing, for example, Ti, Mg, and a halogen as essential components. The first propylene polymer component (a) can be prepared by employing a catalyst system and conditions that provide a polymerization rate of 2000 g or more per hour per gram of catalyst during monomer polymerization. Here, "1 gram of catalyst" refers to 1 gram of a solid catalyst containing, as essential components, Ti, Mg, and a halogen.

[0102] Specifically, the catalyst that can be suitably used is, for example, a catalyst (solid catalyst component) produced by the production method described in JP-A No. 2003-105020.

[0103] The first propylene polymer component (a) can be prepared, for example, by solvent polymerization using an inert solvent such as a hydrocarbon, e.g., hexane, heptane, octane, decane, cyclohexane, methylcyclohexane, benzene, toluene, or xylene; bulk polymerization using a liquid monomer as a solvent; or gas-phase polymerization carried out in a gaseous monomer. Among these, bulk polymerization and gas-phase polymerization are preferred because of their ease of post-treatment.

[0104] The polymerization temperature of the first propylene polymer component (a) is usually 20 to 150° C., and preferably 35 to 95° C. Polymerization within such a temperature range is preferred from the viewpoint of improving productivity and also from the viewpoint of achieving a desired quantitative ratio between the first propylene polymer component (a) and the second propylene polymer component (b).

[0105] The polymerization rate during polymerization of the first propylene polymer component (a) is preferably 2000 g or more per g of catalyst and per hour using a preparation method that can increase production efficiency, suppress a decrease in heat resistance and coloration due to catalyst residue in the polymer, and eliminate the need for catalyst removal.

[0106] As already explained, the second propylene polymer component (b) is preferably prepared by preparing the first propylene polymer component (a) in a first-stage polymerization reactor and then polymerizing it in a second-stage polymerization reactor, and a polymerization method such as solvent polymerization, bulk polymerization, gas-phase polymerization, or a combination thereof can be used. In particular, bulk polymerization, gas-phase polymerization, or a combination thereof is preferred because it can increase the polymerization activity and facilitates post-treatment.

[0107] From the viewpoint of improving production efficiency and achieving a favorable ratio between the first propylene polymer component (a) and the second propylene polymer component (b), the polymerization rate in the preparation of the second propylene polymer component (b) is preferably adjusted by the polymerization conditions so that it is at least twice the polymerization rate in the preparation of the first propylene polymer component (a) per gram of catalyst per hour, and more preferably at least three times the polymerization rate in the preparation of the first propylene polymer component (a). The polymerization temperature may be the same as or different from the polymerization temperature of the first propylene polymer component (a). The polymerization temperature in the preparation of the second propylene polymer component (b) is usually 20 to 150°C, and preferably 35 to 95°C.

[0108] (2) Component (B) Hydrazide Compound In this embodiment, the propylene-based resin composition may further contain component (B) a hydrazide compound.

[0109] In the present embodiment, the component (B) hydrazide compound functions as a metal deactivator (copper inhibitor) and is added for the purpose of preventing deterioration of a molded article obtained by molding the propylene-based resin composition of the present embodiment, which deterioration is caused, for example, by contact between the molded article and metal at the electrical contact points of a connector of a wire harness.

[0110] In this embodiment, the hydrazide compound refers to a phenyl or phenol compound containing one or more groups represented by -C(=O)-NH-.

[0111] Specifically, the hydrazide compound that can be suitably used in this embodiment is a hydrazide compound represented by the following formula (1).

[0112] [ka]

[0113] In the formula (1), R1 and R2 each independently represent an alkyl group having 1 to 8 carbon atoms.

[0114] In this specification, an "alkyl group" may have a substituent. Unless otherwise specified, an "alkyl group" may be linear, branched, or cyclic. The number of carbon atoms in an alkyl group, not including the number of carbon atoms in substituents, is usually 1 to 10, preferably 1 to 8, and more preferably 1 to 4.

[0115] Specific examples of the alkyl group include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a tert-butyl group, an n-pentyl group, an isoamyl group, a 2-ethylbutyl group, an n-hexyl group, a cyclohexyl group, an n-heptyl group, a cyclohexylmethyl group, a cyclohexylethyl group, an n-octyl group, a 2-ethylhexyl group, a 3-n-propylheptyl group, an adamantyl group, an n-decyl group, a 3,7-dimethyloctyl group, and a 2-ethyloctyl group.

[0116] Specific examples of the alkyl having a substituent include a methyl group and a tert-butyl group.

[0117] It is preferable that R1 and R2 are each independently a methyl group and a tert-butyl group, and from the viewpoint of suppressing coloration of the molded body and achieving both rigidity and copper damage prevention performance, it is even more preferable that R1 and R2 are a tert-butyl group.

[0118] That is, in this embodiment, it is preferable to use, as the hydrazide compound of component (B), 2',3-bis[3-[3,5-di-tert-butyl-4-hydroxyphenyl]propionyl]propionohydrazide, which is the hydrazide compound (B-1) represented by the following formula (B-1):

[0119] [ka]

[0120] As the hydrazide compound (B-1), for example, a commercially available product, "IRGANOX MD1024" manufactured by BASF Japan Ltd., can be used.

[0121] In the propylene-based resin composition of the present embodiment, the amount (content) of the hydrazide compound represented by the formula (1) is typically 0.01 to 10 parts by mass, preferably 0.05 to 1.0 part by mass, and more preferably 0.05 to 0.5 part by mass, per 100 parts by mass of the propylene-based polymer of component (A), from the viewpoints of effectively suppressing deterioration of the molded article due to metal and reducing costs.

[0122] Use of the above-mentioned compound as the component (B) hydrazide compound can effectively suppress deterioration of the molded article due to contact with metal, and can improve the melt strength, fluidity during melting, and rigidity of the molded article of the propylene-based resin composition.

[0123] (3) Component (C) Nucleating Agent In this embodiment, the propylene-based resin composition may further contain component (C) a nucleating agent.

[0124] In this embodiment, component (C), the nucleating agent, is a component added to promote the crystallization of polypropylene.

[0125] Any suitable conventional nucleating agent can be used as component (C), the nucleating agent. Examples of nucleating agents include sorbitol-based nucleating agents, metal phosphate nucleating agents, metal carboxylate nucleating agents, and rosin-based nucleating agents. Examples of metal carboxylate nucleating agents include aluminum hydroxy-di(p-tert-butylbenzoate).

[0126] As the nucleating agent, hydroxy-di(p-tert-butylbenzoate)aluminum, for example, a commercially available product "AL-PTBBA" manufactured by Japan Chemtech Co., Ltd. can be used.

[0127] In the propylene-based resin composition of the present embodiment, it is preferable to use a metal salt represented by the following formula (2) as the component (C) nucleating agent.

[0128] [ka]

[0129] In formula (2), M1 and M2 each independently represent a sodium atom or a hydrogen atom, and at least one of M1 and M2 is a sodium atom; R4, R5, R6, R7, R8, R9, R 10 , R 11 , R 12 , and R 13 are each independently a group selected from the group consisting of a hydrogen atom, an alkyl group having 1 to 9 carbon atoms, a hydroxyl group, an alkoxy group having 1 to 9 carbon atoms, an alkyleneoxy group having 1 to 9 carbon atoms, an amino group, an alkylamino group having 1 to 9 carbon atoms, a halogen atom, and a phenyl group. 10 , R 11 , R 12 , and R 13 When two or more of the groups are alkyl groups, these groups may be bonded to each other to form a hydrocarbon ring.

[0130] In this embodiment, from the viewpoint of improving the rigidity of a molded article obtained by molding the propylene-based resin composition, it is preferable to use disodium bicyclo(2,2,1)heptane-2,3-dicarboxylate (nucleating agent (C-1)) represented by the following formula (C-1) or 1,2-cyclohexanedicarboxylate calcium salt (nucleating agent (C-2)) represented by the following formula (C-2) as the metal salt serving as the nucleating agent (component (C)). In other words, it is preferable that the propylene-based resin composition of this embodiment contains, as the nucleating agent, a compound represented by the following formula (C-1) or a compound represented by the following formula (C-2).

[0131] [ka]

[0132] As the metal salt serving as the nucleating agent (C), commercially available products can also be used. Examples of commercially available nucleating agents (C-1) include HPN-68L (trade name, manufactured by Milliken). Examples of commercially available nucleating agents (C-2) include HPN-20E (trade name, manufactured by Milliken).

[0133] In this embodiment, the amount of the nucleating agent added is preferably 0.01 parts by mass or more, more preferably 0.05 parts by mass or more, and preferably 3 parts by mass or less, more preferably 1 part by mass or less, and preferably 0.05 to 1 part by mass, relative to 100 parts by mass of the propylene-based polymer, component (A), already described.

[0134] By using the above compound as the nucleating agent (component (C)), the degree of crystallization of the propylene polymer contained in the propylene resin composition can be improved, and the rigidity of the molded article can be improved.

[0135] (4)Optional components The propylene-based resin composition of the present embodiment may contain further optional components in addition to the components already described above.

[0136] Examples of such optional components include neutralizing agents, antioxidants, inorganic fillers, flame retardants, elastomers, antioxidants, ultraviolet absorbers, lubricants, antistatic agents, antiblocking agents, processing aids, organic peroxides, colorants (e.g., inorganic pigments, organic pigments), pigment dispersants, foaming agents, foam nucleating agents, plasticizers, crosslinking agents, crosslinking aids, brightness enhancers, antibacterial agents, light diffusing agents, and molecular weight modifiers.

[0137] The propylene-based resin composition of the present embodiment may contain one of these optional components alone, or may contain two or more optional components in any combination at any ratio.

[0138] (i) Neutralizing agent In the present embodiment, any suitable conventionally known antioxidant can be used as the neutralizing agent, and two or more neutralizing agents may be used in combination.

[0139] Specific examples of the neutralizing agent include hydrotalcite and calcium stearate. In this embodiment, it is preferable to use calcium stearate (for example, manufactured by Sakai Chemical Industry Co., Ltd.) as the neutralizing agent.

[0140] When the propylene-based resin composition of this embodiment contains a neutralizing agent, the content of the neutralizing agent in the propylene-based resin composition is usually 0 part by mass or more, preferably 0.01 part by mass or more, more preferably 0.03 part by mass or more, and preferably 0.5 part by mass or less, and more preferably 0.1 part by mass or less, relative to 100 parts by mass of the total amount of the propylene-based polymer (Component (A)) contained in the propylene-based resin composition. Setting the content of the neutralizing agent in this manner can effectively suppress coloration of a molded article obtained by molding the propylene-based resin composition, and can improve rigidity and copper damage prevention performance.

[0141] (ii) antioxidants In the present embodiment, any suitable antioxidant known in the art can be used as the antioxidant. Two or more types of antioxidants may be used in combination.

[0142] Specific preferred examples of the antioxidant include phenol-based antioxidants (e.g., Sumilizer GA80 (manufactured by Sumitomo Chemical Co., Ltd.)), sulfur-based antioxidants (e.g., Sumilizer TPM (manufactured by Sumitomo Chemical Co., Ltd.)), and phosphorus-based antioxidants (e.g., SONGNOX6260 (manufactured by Songwon Chemical Co., Ltd.)).

[0143] When the propylene-based resin composition of this embodiment contains an antioxidant, the content of the antioxidant in the propylene-based resin composition is usually 0 part by mass or more, preferably 0.01 part by mass or more, more preferably 0.05 part by mass or more, preferably 1 part by mass or less, more preferably 0.5 parts by mass or less, and even more preferably 0.3 parts by mass or less, relative to 100 parts by mass of the total amount of the propylene-based polymer (Component (A)) contained in the propylene-based resin composition. Setting the content of the antioxidant in this manner can effectively suppress discoloration of a molded article obtained by molding the propylene-based resin composition, and can improve rigidity and copper damage prevention performance.

[0144] (iii) Inorganic filler The propylene-based resin composition according to this embodiment may further contain an inorganic filler from the viewpoint of improving mechanical properties, electrical properties, and the like.

[0145] Examples of inorganic fillers include (i) fibrous inorganic fillers and (ii) non-fibrous inorganic fillers. Two or more inorganic fillers may be used in combination. These will be specifically described below.

[0146] (i) Fibrous inorganic filler In this embodiment, the fibrous inorganic filler preferably has an average fiber diameter of 0.2 μm to 20 μm, an average fiber length of 5 μm to 200 μm, and an aspect ratio of 10 to 30. From the viewpoint of improving the rigidity and appearance of the molded article, it is more preferable that the average fiber diameter is 0.3 μm to 10 μm, the average fiber length is 7 μm to 150 μm, and the aspect ratio is 12 to 25.

[0147] The average fiber diameter and average fiber length of the fibrous inorganic filler are, for example, the average values ​​of the fiber diameter and fiber length measured by randomly selecting 50 or more fibers from an image of the fibrous inorganic filler obtained by an electron microscope, and the aspect ratio can be calculated using these average values.

[0148] Examples of fibrous inorganic fillers include fibrous magnesium oxysulfate, potassium titanate fiber, magnesium hydroxide fiber, aluminum borate fiber, calcium silicate fiber, calcium carbonate fiber, carbon fiber, glass fiber, and metal fiber. Of these, fibrous magnesium oxysulfate and calcium silicate fiber are preferred.

[0149] The fibrous inorganic filler may be used as it is, or may be surface-treated with, for example, a silane coupling agent or a metal salt of a higher fatty acid in order to improve interfacial adhesion and dispersibility.

[0150] Examples of higher fatty acid metal salts used for the surface treatment include calcium stearate, magnesium stearate, and zinc stearate.

[0151] In this embodiment, examples of the form of the fibrous inorganic filler include powder, flake, and granule. In this embodiment, any of the above-mentioned forms of the fibrous inorganic filler can be used. It is preferable to use a granular fibrous inorganic filler because it is easy to handle.

[0152] (ii) Non-fibrous inorganic fillers Examples of non-fibrous inorganic fillers include talc, mica, calcium carbonate, barium sulfate, magnesium carbonate, clay, alumina, silica, calcium sulfate, silica sand, carbon black, titanium oxide, magnesium hydroxide, zeolite, molybdenum, diatomaceous earth, sericite, shirasu, calcium hydroxide, calcium sulfite, sodium sulfate, bentonite, graphite, etc. From the viewpoints of improving the impact strength and appearance of the molded article, it is preferable to use talc.

[0153] The average particle size of the non-fibrous inorganic filler is preferably 10 μm or less, more preferably 5 μm or less. Here, the average particle size of the non-fibrous inorganic filler can be determined as the 50% equivalent particle size D50 from an integral distribution curve obtained by suspending the non-fibrous inorganic filler in a dispersion medium such as water or alcohol and subjecting the suspension to a sieve size reduction method using a centrifugal sedimentation particle size distribution analyzer.

[0154] The non-fibrous inorganic filler may be used as is, or may be surface-treated with a silane coupling agent, a titanium coupling agent, or a surfactant to improve interfacial adhesion and dispersibility. Examples of the surfactant include higher fatty acids, higher fatty acid esters, higher fatty acid amides, and higher fatty acid salts.

[0155] The fibrous inorganic filler may be used as it is, or may be surface-treated with a silane coupling agent or a metal salt of a higher fatty acid in order to improve interfacial adhesion and dispersibility.

[0156] 3. Properties of propylene-based resin compositions (1) Melt flow rate (MRF) The melt flow rate of the propylene-based resin composition of this embodiment at a temperature of 230° C. and a load of 2.16 kgf is preferably 0.1 g / 10 min or more, from the viewpoint of improving the molding processability of the propylene-based resin composition.

[0157] 4. Method for producing propylene-based resin composition The propylene-based resin composition of the present embodiment can be produced by melt-kneading the components already described as raw materials. The temperature during melt-kneading may be 180°C or higher, 180 to 300°C, or 180 to 250°C.

[0158] Examples of production apparatuses for melt-kneading to produce the propylene-based resin composition of the present embodiment include a Banbury mixer, a single-screw extruder, and a twin-screw co-rotating extruder.

[0159] The order of kneading the raw materials is not particularly limited. For example, all the raw materials may be kneaded by being charged into a production apparatus at once, or some of the selected components may be kneaded and then the resulting kneaded mixture may be kneaded with other components.

[0160] The properties of the propylene-based resin composition of this embodiment are not particularly limited. The propylene-based resin composition of this embodiment can be in the form of, for example, a strand (filament), a sheet, a plate, or a pellet. The pellet shape can be produced, for example, by forming a strand of the propylene-based resin composition and then cutting it to an appropriate length.

[0161] From the viewpoint of improving the molding processability of the propylene-based resin composition and increasing the production stability of molded articles, the propylene-based resin composition before being molded into a molded article is preferably in the form of pellets having a length of about 1 to 50 mm.

[0162] The propylene-based resin composition of the present embodiment can effectively suppress coloration of the molded article, and can achieve both the rigidity and copper damage prevention performance required when the molded article is applied to a connector of a vehicle wire harness, in particular.Furthermore, it is possible to provide a connector of a vehicle wire harness that can achieve both weight reduction and rigidity.

[0163] 5. Molded body The propylene-based resin composition of the present embodiment can be suitably used as a material for forming a molded article, and is particularly preferably used as a material for injection molding.

[0164] An example of using the propylene-based resin composition of this embodiment as an injection molding material to produce an injection-molded article will be described below.

[0165] The injection-molded article is an article molded from the propylene-based resin composition of the present embodiment. Injection-molded articles generally have excellent dimensional stability.

[0166] Injection-molded articles can be produced by injection molding, including, for example, 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.

[0167] The molded article (injection molded article) of this embodiment can be produced by the above-described production method in any suitable shape and size depending on the application.

[0168] The injection-molded article of the present embodiment is preferably used for, for example, material applications for vehicle-related members, particularly for automobile interior and exterior materials, home appliance materials, and containers, and is more preferably used for material applications for vehicle-related members. Here, examples of material applications for vehicle-related members include automobile interior and exterior parts such as door trims, pillars, instrument panels, and bumpers.

[0169] The injection-molded article of the present embodiment has low colorability, good rigidity and copper damage prevention performance, and can achieve both lightweight and rigidity, and therefore can be suitably applied to connectors of wire harnesses, which are vehicle-related components.

[0170] Here, an example of the configuration of a connector for a vehicle wire harness according to the present embodiment to which the propylene-based resin composition according to the present embodiment can be suitably applied will be described with reference to the drawings.

[0171] Fig. 1 is a diagram schematically illustrating a configuration example of a connector of a vehicle wire harness, and Fig. 2 is a diagram schematically illustrating a cut end surface of the connector of the vehicle wire harness taken along the dashed line AA shown in Fig. 1.

[0172] As shown in FIGS. 1 and 2, a connector 10 of a vehicle wire harness is provided with one or more insertion portions 10a.

[0173] The insertion portions 10a are configured as through holes that extend in a direction perpendicular to the thickness direction and are arranged parallel to one another. In this configuration example, the shapes of the cut end faces when the insertion portions 10a are cut in a direction perpendicular to the extension direction are identical to one another.

[0174] 2, the connector 10 of the vehicle wire harness is provided with one or more lance portions 12. In the illustrated example, one lance portion 12 is provided for each insertion portion 10a, which is a through hole, but two or more lance portions 12 may be provided for each insertion portion 10a, or may be provided for only some of the multiple insertion portions 10a.

[0175] In the illustrated example, the lance portion 12 is provided so as to protrude in a wedge shape from a wall surface defining the insertion portion 10a, which is a through hole, in the vertical direction, which is perpendicular to the extension direction of the insertion portion 10a.

[0176] In the connector 10 of the vehicle wire harness of this embodiment, the height 12b including the maximum height 12a in a direction perpendicular to the wall surface defining the insertion portion 10a of the lance portion 12, i.e., the thickness of the lance portion 12, is preferably 2 mm or less, more preferably 1.5 mm or less, from the viewpoint of miniaturization and high-speed moldability of the connector, and is preferably 0.2 mm or more, more preferably 0.4 mm or more, and is preferably in the range of 0.2 mm to 1.5 mm, and is preferably in the range of 0.4 mm to 1.0 mm, from the viewpoint of mechanical strength.

[0177] As shown in FIG. 2, at least a portion of the terminal portion 20 is shaped to fit into the lance portion 12 in accordance with the shape of the lance portion 12, thereby enabling the terminal portion 20 to be detachably fixed to the insertion portion 10a, i.e., the connector 10 of the vehicle wire harness; in other words, in this configuration example, the lance portion 12 has a recess that can be fitted into and locked thereto.

[0178] Since the connector 10 and the terminal portion 20 of the vehicle wire harness have the above-described configuration, the terminal portion 20 is removably fixed to the connector 10 of the vehicle wire harness, and the connector 10 of the vehicle wire harness and the terminal portion 20 are electrically connected. [Example]

[0179] The components used in the examples and comparative examples are shown below. (1) Component (A) Propylene-Based Polymer (A-1) Propylene-based polymer (component (A-1)) A propylene homopolymer (polypropylene), component (A-1), was prepared using the polymerization catalyst described in Example 1 of JP-A-11-228629 and in accordance with the polymerization method and polymerization conditions described in Example 1.

[0180] Specifically, first, a first step was carried out in which liquid propylene, triethylaluminum, tert-butyl-n-propyldimethoxysilane, and a polymerization catalyst were continuously supplied to a first stainless steel reaction vessel to polymerize a first propylene polymer component (a).

[0181] Next, without deactivating the polymerization catalyst, the polymerization catalyst and the first propylene polymer component (a) were transferred to a second reaction vessel connected in series to the first reaction vessel, and a second step was carried out in which a second propylene polymer component (b) having a molecular weight different from that of the first propylene polymer component (a) was polymerized while further supplying propylene and hydrogen.

[0182] The intrinsic viscosity [η]b of the second propylene polymer component (b) was calculated by the following formula based on the intrinsic viscosities [η]a and [η]T determined as above. Formula: [η]b=([η]T×100-[η]a×Wa) / Wb

[0183] During the ceremony, [η]T represents the intrinsic viscosity of component (A-1) propylene homopolymer, [η] represents the intrinsic viscosity of the first component (a), Wa represents the content (mass%) of the first propylene polymer component (a), Wb represents the content (mass %) of the second propylene polymer component (b).

[0184] In this way, a propylene polymer (Component (A-1)) was obtained, which was a propylene homopolymer consisting of 19% by mass of a first propylene polymer component (a) having an intrinsic viscosity [η] of 7.1 dL / g and 81% by mass of a second propylene polymer component (b) having an intrinsic viscosity [η] of 0.76 dL / g. The physical properties of the obtained propylene polymer (Component (A-1)) were as follows:

[0185] Melt flow rate (230°C, load 2.16 kgf): 11.5 g / 10 min Weight average molecular weight (Mw) 530000, number average molecular weight (Mn) 58000, molecular weight distribution (Mw / Mn) 9.1, intrinsic viscosity [η]T: 1.94dL / g

[0186] (A-2) Propylene-based polymer (component (A-2)) A propylene homopolymer (A-2) was produced as a resin powder by gas phase polymerization using a solid catalyst component produced by the method described in JP 2003-105020 A. The resulting propylene homopolymer had a melt flow rate (230°C, load 2.16 kgf): 0.5 g / 10 min Weight average molecular weight (Mw) 730000, number average molecular weight (Mn) 190000, molecular weight distribution (Mw / Mn) 3.8, intrinsic viscosity [η]T: 2.96dL / g

[0187] (A-3) Propylene-based polymer (component (A-3)) A propylene homopolymer (A-3) was produced as a resin powder by gas phase polymerization using a solid catalyst component produced by the method described in JP 2003-105020 A. The resulting propylene homopolymer had a melt flow rate (230°C, load 2.16 kgf): 120 g / 10 min Weight average molecular weight (Mw) 180000, number average molecular weight (Mn) 49000, molecular weight distribution (Mw / Mn) 3.8, intrinsic viscosity [η]T: 0.93dL / g

[0188] (A-4) Propylene-based polymer (component (A-4)) A propylene homopolymer (A-4) was produced as a resin powder by gas phase polymerization using a solid catalyst component produced by the method described in JP 2003-105020 A. The resulting propylene homopolymer had a melt flow rate (230°C, load 2.16 kgf): 8.0 g / 10 min Weight average molecular weight (Mw) 365000, number average molecular weight (Mn) 105000, molecular weight distribution (Mw / Mn) 3.5, intrinsic viscosity [η]T: 1.61dL / g

[0189] (2) Component (B) Hydrazide Compound As the hydrazide compound of component (B), 2',3-bis[3-[3,5-di-tert-butyl-4-hydroxyphenyl]propionyl]propionohydrazide (manufactured by BASF Japan Ltd., IRGANOX MD1024), which is a hydrazide compound (B-1) represented by the following formula (B-1), and 2-hydroxy-N-1H-1,2,4-triazol-3-yl-benzamide (manufactured by ADEKA Corporation, Adeka STAB CDA-1M), which is a hydrazide compound (B-2) represented by the following formula, were used.

[0190] [ka]

[0191] (3) Component (C) Nucleating Agent As the nucleating agent for component (C), a nucleating agent (C-1) (Hyperform HPN-68L, manufactured by Milliken), which is a compound represented by the following formula (C-1), and a nucleating agent (C-2) (Hyperform HPN-20E, manufactured by Milliken), which is a compound represented by the following formula (C-2), were used.

[0192] [ka]

[0193] Details of the nucleating agents (C-1) and (C-2) are as follows: (i) Nucleating Agent (C-1) Chemical name of the main component: Disodium (1R,2R,3S,4S)-bicyclo[2.2.1 ]heptane-2,3-dicarboxylate Content of main component: 80% by mass

[0194] (ii) Nucleating Agent (C-2) Chemical name of the main ingredient: 1,2-cyclohexanedicarboxylic acid calcium salt CAS Reg. NO.: 491589-22-1 Content of main component: 66% by mass Chemical name of secondary ingredient: Zinc stearate CAS Reg. No.: 557-05-1 Sub-component content: 34% by mass Average particle size: 2.6 μm (measured using a laser diffraction particle size distribution analyzer (Sympatec HELOS (product name))

[0195] (4) Neutralizer The neutralizing agent used was calcium stearate (manufactured by Sakai Chemical Industry Co., Ltd.) with the following CAS numbers: CAS.1592-23-0

[0196] (5) Antioxidants The following (i) to (iii) were used as antioxidants (CAS numbers are given): (i) Sumilizer GA80 (Sumitomo Chemical Co., Ltd.) CAS.90498-90-1 (ii) SONGNOX6260 (manufactured by Songwon) CAS.26741-53-7 (iii) Sumilizer TPM (Sumitomo Chemical Co., Ltd.) CAS.16545-54-3

[0197] [Example 1] 100 parts by mass of component (A-1) propylene-based polymer, 0.1 parts by mass of hydrazide compound (B-1), 0.2 parts by mass of nucleating agent (C-1), 0.05 parts by mass of calcium stearate, 0.1 parts by mass of antioxidants Sumilizer GA80, 0.05 parts by mass of SONGNOX 6260, and 0.2 parts by mass of Sumilizer TPM were weighed and uniformly mixed. The mixture was then introduced into the most upstream raw material inlet of a twin-screw kneader "TEX44αII" manufactured by The Japan Steel Works, Ltd., and melt-kneaded at a cylinder temperature of 230°C, a discharge rate of 50 kg / h, and a screw rotation speed of 200 rpm to obtain pelletized propylene-based resin composition (a1). The materials used are also shown in Table 1 below. Note that all values ​​in Table 1 represent parts by mass.

[0198] Next, the propylene-based resin composition (a1) was evaluated by the following measurement methods.

[0199] (1) Melt flow rate (MFR, unit: g / 10 min) The melt flow rate (MFR) was measured at 230°C under a load of 21 N in accordance with ASTM D1238.

[0200] (2) Color (appearance: visual evaluation) The pelletized propylene-based resin composition prepared as described above was fed into a mold cavity through the gate of an injection molding machine and injection-molded to obtain a plate-shaped molded product measuring 90 mm (width) × 150 mm (length) × 1 mm (thickness). The injection molding machine and injection molding conditions used are as follows: Injection molding machine: Toshiba Corporation, IS100EN (mold clamping force 100 tons, cylinder diameter 36 mm) Mold cavity shape: 90mm (width) x 150mm (length) x 1mm (thickness) rectangular parallelepiped Gate: One gate opening in the center of the surface that defines the 90 mm (width) of the mold cavity Cylinder temperature: 240℃ Mold temperature: 50℃ Injection speed: 27mm / sec

[0201] The appearance (surface color) of the obtained flat plate-shaped molded article was visually evaluated. A white surface was evaluated as good (◯), and a pale yellow surface was evaluated as poor (×). The results are shown in Table 1 below.

[0202] (3) Weight average molecular weight (Mw), number average molecular weight (Mn), molecular weight distribution (Mw / Mn) The polystyrene-equivalent weight-average molecular weight, number-average molecular weight, and molecular weight distribution were measured using the following method. Tetrahydrofuran was used as the solvent, and the sample solution concentration was adjusted to 0.5 mg / mL. Two GPC columns, Plus Pore Series Poly Pore 7.5 mm ID x 300 mm (Agilent Technologies), were connected in series. The mobile phase was tetrahydrofuran, and the flow rate was 1 mL / min. The column oven temperature was set to 35°C, and a refractive index detector was used (RID cell temperature: 35°C). The sample solution injection volume was 100 μL. PStQuick Kit-H (Tosoh Corporation) was used as a calibration standard for the GPC column.

[0203] (4) 1mm flexural modulus (unit: MPa) and flexural strength (unit: MPa) ASTM D790 Type 4 dumbbells were punched out from the 90 x 150 x 1 mm plate-shaped molded product obtained as described above, and the flexural modulus and flexural strength at 23°C were measured in accordance with ASTM D790. The results are shown in Table 1 below.

[0204] [Example 2] A pellet-shaped propylene-based resin composition was prepared in the same manner as in Example 1, except that the nucleating agent (C-2) was used instead of the nucleating agent (C-1), and the molded article was evaluated. The results are shown in Table 1 below.

[0205] [Example 3] A pellet-shaped propylene-based resin composition was prepared in the same manner as in Example 1, except that the hydrazide compound (B-1) and the nucleating agent (C-1) were not used, and the molded article was evaluated. The results are shown in Table 1 below.

[0206] [Comparative Examples 1 to 3] Pellets of propylene-based resin compositions were prepared and molded articles were evaluated in the same manner as in Example 3, except that propylene-based polymers were used in the ratios shown in Table 1. The results are shown in Table 1 below.

[0207] [Table 1] [Explanation of symbols]

[0208] 10. Vehicle wiring harness connector 10a Insertion part 12 Lance Club 12a Maximum height 12b height 20 Terminal section

Claims

1. The propylene-based resin composition includes a propylene-based polymer having a weight average molecular weight of 500,000 to 1,000,000 in terms of polystyrene, determined by a GPC method, and a molecular weight distribution (weight average molecular weight / number average molecular weight) of 6 to 10, and a hydrazide compound which is a phenyl or phenol compound containing one or more groups represented by -C(=O)-NH-, A connector for a vehicle wire harness having one or more insertion portions and one or more lance portions provided so as to protrude from a wall surface defining the insertion portions, wherein the thickness of the lance portions is 1 mm or less.

2. the melt flow rate of the propylene polymer measured under conditions of a temperature of 230°C and a load of 2.16 kgf is 0.1 to 15 g / 10 min, 2. The connector for a vehicle wire harness according to claim 1, wherein the propylene-based polymer has an intrinsic viscosity of 1.5 dL / g or more.

3. 3. The connector for a vehicle wire harness according to claim 1, wherein the propylene-based resin composition further contains a nucleating agent, and the hydrazide compound is a hydrazide compound represented by the following formula (1): 【Chemical 1】 (In the formula (1), R １ and R ２ each independently represents an alkyl group having 1 to 8 carbon atoms.

4. In the formula (1), R １ and R ２ The connector for a vehicle wire harness according to claim 3, wherein is a tert-butyl group.

5. The connector of the vehicle wire harness according to claim 3 or 4, wherein the nucleating agent comprises a compound represented by the following formula (C-1) or a compound represented by the following formula (C-2): 【Chemistry 2】

6. the propylene-based polymer comprises a first propylene polymer component and a second propylene polymer component; the first propylene polymer component has an intrinsic viscosity of 5 to 8 dL / g; The connector for a vehicle wire harness according to any one of claims 1 to 5, wherein the second propylene polymer component has an intrinsic viscosity of 0.5 to 2 dL / g.

7. the proportion of the first propylene polymer component in the entire propylene-based polymer is 10% by mass or more and 20% by mass or less, 7. The connector for a vehicle wire harness according to claim 6, wherein the second propylene polymer component accounts for 80% by mass or more and 90% by mass or less of the entire propylene-based polymer.

8. A propylene polymer having a polystyrene-equivalent weight average molecular weight of 500,000 to 1,000,000 as determined by a GPC method, a molecular weight distribution (weight average molecular weight / number average molecular weight) of 6 to 10, a melt flow rate of 0.1 to 15 g / 10 min as measured at a temperature of 230°C under a load of 2.16 kgf, and an intrinsic viscosity of 1.5 dL / g or more; A nucleating agent; a hydrazide compound represented by the following formula (1): A propylene-based resin composition comprising: 【Chemistry 3】 (In the formula (1), R １ and R ２ each independently represents an alkyl group having 1 to 8 carbon atoms.

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