Ethylene resin composition and molded article

Abstract

One embodiment of the present invention relates to: an ethylene-based resin composition containing 100 parts by mass of an ethylene-based polymer composition (A) and 1-30 parts by mass of a carbon-based filler (B); the ratio ([eta] 1330 / [eta] 13.3) of the shear viscosity [eta] 1330 measured at a temperature of 250 DEG C and a shear rate of 1330 s <-1 > to the shear viscosity [eta] 13.3 measured at a temperature of 250 DEG C and a shear rate of 13.3 s <-1 > is less than 0.027.

Description

TECHNICAL FIELD

[0001] One embodiment of the present application relates to an ethylene-based resin composition or a molded body using the same. BACKGROUND

[0002] An ethylene-based polymer having an extremely high molecular weight, so-called ultrahigh molecular weight ethylene-based polymer, has excellent impact resistance, wear resistance, chemical resistance, and strength, and has excellent characteristics as an engineering plastic compared to general ethylene-based polymers.

[0003] It is known that such an ultrahigh molecular weight ethylene-based polymer can be obtained by a known catalyst such as a so-called Ziegler catalyst composed of a halogen-containing transition metal compound and an organic metal compound, a magnesium compound-supported catalyst, and the like.

[0004] An ultrahigh molecular weight ethylene-based polymer is difficult to be melt-molded as a general resin molding method because of its high molecular weight. As a method for producing a molded body of an ultrahigh molecular weight ethylene-based polymer, a plunger extrusion method is a method that has been generally used (Patent Literature 1).

[0005] In addition, as a method for improving the sliding property and mechanical properties of an ethylene-based polymer, a method in which cellulose fibers are dispersed in an ethylene-based polymer has been proposed (Patent Literature 2).

[0006] On the other hand, depending on the use, there are cases where a composition that is an ultrahigh molecular weight ethylene-based polymer composition and in which the electrical conductivity is improved is required. As a composition containing an ultrahigh molecular weight ethylene-based polymer and in which the electrical conductivity is improved, a composition containing an ethylene-based polymer and a carbon-based filler and in which the melt flow rate (MFR, measurement temperature 230°C, 10 kg load) is in the range of 0.1 to 20 g / 10 minutes has been proposed (Patent Literature 3).

[0007] Prior Art Documents

[0008] Patent Literature

[0009] Patent Literature 1: Japanese Patent Application Laid-Open No. 55-28896

[0010] Patent Literature 2: Japanese Patent Application Laid-Open No. 2019-35005

[0011] Patent Literature 3: International Publication No. 2022 / 038941 SUMMARY

[0012] PROBLEMS TO BE SOLVED BY THE INVENTION

[0013] The composition of Patent Literature 3 has excellent characteristics in that the electrical conductivity is excellent and further, although an ultrahigh molecular weight ethylene-based polymer is contained, it can be molded by injection molding, but depending on the use, there are cases where it is required to improve the wear resistance.

[0014] One embodiment of the present application provides a composition which is excellent in both electric conductivity and injection moldability, and further excellent in wear resistance.

[0015] Means for solving the problem

[0016] The present inventors have conducted studies, and as a result, have found that the aforementioned problem can be solved according to the following configuration examples. The configuration of the present application is indicated in, for example, [1] to [8] below.

[0017] Note that, in the present specification, "A to B" indicating a numerical range means A or more and B or less.

[0018] [1] An ethylene-based resin composition (X) containing 100 parts by mass of an ethylene-based polymer composition (A) and 1 to 30 parts by mass of a carbon-based filler (B), having a shear viscosity η measured at a temperature of 250°C and a shear rate of 1330 s -1 a shear viscosity η measured at a temperature of 250°C and a shear rate of 13.3 s 1330 a shear viscosity η measured at a temperature of 250°C and a shear rate of 13.3 s -1 a shear viscosity η measured at a temperature of 250°C and a shear rate of 13.3 s 13.3 a ratio (η 1330 / η 13.3 ) of 0.027 or less.

[0019] [2] The ethylene-based resin composition (X) according to [1], wherein the aforementioned carbon-based filler (B) is a carbon nanotube.

[0020] [3] The ethylene-based resin composition (X) according to [1] or [2], wherein the aforementioned ethylene-based polymer composition (A) contains 20 to 60 parts by mass of an ultrahigh molecular weight ethylene-based polymer (al) having an intrinsic viscosity [η] of 10 dl / g to 40 dl / g measured in decalin at 135°C, and 40 to 80 parts by mass of a low molecular weight or high molecular weight ethylene-based polymer (a2) having an intrinsic viscosity [η] of 0.1 dl / g to 9 dl / g measured in decalin at 135°C (wherein the total amount of the ultrahigh molecular weight ethylene-based polymer (al) and the low molecular weight or high molecular weight ethylene-based polymer (a2) is 100 parts by mass).

[0021] [4] The ethylene-based resin composition (X) according to any one of [1] to [3], wherein the melt flow rate (MFR) under a load of 10 kg at 190°C is 0.1 g / 10 minutes or less.

[0022] [5] The ethylene-based resin composition (X) according to any one of [1] to [4], wherein the aforementioned ethylene-based polymer composition (A) has an intrinsic viscosity [η] of 3.0 to 15 dl / g and a density of 930 to 980 kg / m3 as measured in decalin at 135°C 3 .

[0023] [6] A molded body comprising the ethylene-based resin composition (X) according to any one of [1] to [5].

[0024] [7] The molded body according to [6], which is an injection-molded body.

[0025] [8] The molded body according to [6] or [7], which is a coating material or a sliding material.

[0026] Effects of the Invention

[0027] According to one embodiment of the present application, it is possible to provide a composition which is excellent in both electric conductivity and injection moldability, and further excellent in wear resistance. DETAILED DESCRIPTION

[0028] Ethylene-based resin composition (X)

[0029] The ethylene-based resin composition (X) (hereinafter also referred to as "resin composition (X)") contains 100 parts by mass of an ethylene-based polymer composition (A) and 1 to 30 parts by mass of a carbon-based filler (B).

[0030] Ethylene-based polymer composition (A)

[0031] The ethylene-based polymer composition (A) preferably contains a specific ultrahigh molecular weight ethylene-based polymer (al) and a specific low molecular weight or high molecular weight ethylene-based polymer (a2) (hereinafter also referred to as "ethylene-based polymer (a2)").

[0032] Ultrahigh molecular weight ethylene-based polymer (al)

[0033] The ultrahigh molecular weight ethylene-based polymer (al) preferably satisfies the following requirement (al-a).

[0034] Requirement (al-a)

[0035] The intrinsic viscosity [η] of the ultrahigh molecular weight ethylene-based polymer (al) as measured in a decalin solvent at 135°C is preferably 10 to 40 dl / g, more preferably 15 to 35 dl / g, and further preferably 20 to 35 dl / g.

[0036] Note that the details of the measurement conditions and the like are as described in the Examples below.

[0037] When the intrinsic viscosity [η] of the ultra-high molecular weight ethylene-based polymer (al) measured in decalin solvent at 135°C is 10 dl / g or more, the wear resistance of the ethylene-based polymer composition (A) easily becomes good. As a result, the wear resistance, self-lubricating property, impact strength, and drug resistance of the resin composition (X) containing the ethylene-based polymer composition (A) and the molded body obtained from the aforementioned resin composition (X) easily become good. In addition, when the intrinsic viscosity [η] of the ultra-high molecular weight ethylene-based polymer (al) measured in decalin solvent at 135°C is 40 dl / g or less, the melt flowability of the ethylene-based polymer composition (A) and the resin composition (X) in which the ultra-high molecular weight ethylene-based polymer (al) is compounded easily becomes high. That is, when the intrinsic viscosity [η] of the ultra-high molecular weight ethylene-based polymer (al) is within the aforementioned range, the ethylene-based polymer composition (A) and the resin composition (X) containing the ultra-high molecular weight ethylene-based polymer (al) can give consideration to both wear resistance and moldability.

[0038] The ultra-high molecular weight ethylene-based polymer (al) is a homopolymer of ethylene, or a copolymer of ethylene and an α-olefin such as propylene, 1-butene, 1-pentene, 1-hexene, 1-octene, 1-decene, 1-dodecene, 4-methyl-1-pentene, or 3-methyl-1-pentene. The ultra-high molecular weight ethylene-based polymer (al) is preferably a homopolymer of ethylene, or a copolymer of ethylene and the aforementioned α-olefin, and is more preferably a homopolymer of ethylene. Here, the main component means a component having the highest content ratio (mol%) among the structural units contained in the polymer.

[0039] [Low molecular weight or high molecular weight ethylene-based polymer (a2)]

[0040] The ethylene-based polymer (a2) preferably satisfies one or more of the following requirements (a2-a) and (a2-b).

[0041] [Requirement (a2-a)]

[0042] The intrinsic viscosity [η] of the ethylene-based polymer (a2) measured in decalin solvent at 135°C is preferably 0.1 to 9.0 dl / g, more preferably 0.1 to 5.0 dl / g, further preferably 0.5 to 3.0 dl / g, and particularly preferably 1.0 to 2.5 dl / g.

[0043] Note that the details of the measurement conditions and the like are described in the Examples section described later.

[0044] When the intrinsic viscosity [η] of the ethylene-based polymer (a2) measured in decalin solvent at 135°C is 0.1 dl / g or more, the wear resistance of the ethylene-based polymer composition (A) easily becomes good. As a result, the wear resistance of the resin composition (X) containing the ethylene-based polymer composition (A) and the molded body obtained from the aforementioned resin composition (X) easily becomes good. In addition, when the intrinsic viscosity [η] of the ethylene-based polymer (a2) measured in decalin solvent at 135°C is 9.0 dl / g or less, the melt flowability of the ethylene-based polymer composition (A) and the resin composition (X) containing the aforementioned ethylene-based polymer composition (A) easily becomes high. That is, when the intrinsic viscosity [η] of the ethylene-based polymer (a2) measured in decalin solvent at 135°C is 0.1 to 9.0 dl / g, the ethylene-based polymer composition (A) and the resin composition (X) in which both the wear resistance and the moldability are excellent are easily obtained. In addition, when the intrinsic viscosity [η] of the ethylene-based polymer (a2) measured in decalin solvent at 135°C is within the aforementioned range, the carbon-based filler (B) used for the production of the resin composition (X) is easily dispersed, and the carbon-based filler (B) can be contained in an amount sufficient to impart the desired electrical conductivity to the resin composition (X).

[0045] [Condition (a2-b)]

[0046] The density of the ethylene-based polymer (a2) is preferably 920 to 985 kg / m 3 , more preferably 940 to 985 kg / m 3 , further preferably 950 to 980 kg / m 3 , more preferably 950 to 975 kg / m 3 , further preferably 960 to 975 kg / m 3 .

[0047] Note that the details of the measurement conditions and the like are described in the column of Examples described later.

[0048] When the density of the ethylene-based polymer (a2) is 920 kg / m 3 or more, the crystallinity of the ethylene-based polymer (a2) is improved to the extent that the surface smoothness of the ethylene-based polymer (a2) is not impaired. Therefore, the ethylene-based polymer composition (A) obtained and the resin composition (X) containing the aforementioned ethylene-based polymer composition (A) have a tendency to have excellent wear resistance. In addition, the density of the polyethylene is generally 985 kg / m 3 or less, and therefore a polyethylene having a density of 985 kg / m 3 or less is used as the ethylene-based polymer (a2).

[0049] The ethylene-based polymer (a2) is a homopolymer of ethylene or a copolymer of ethylene and an α-olefin. It is preferable that the ethylene-based polymer (a2) be a homopolymer of ethylene.

[0050] As the α-olefin constituting the aforementioned copolymer, a linear or branched α-olefin having 3 to 20 carbon atoms can be given, and specifically, propylene, 1-butene, 1-pentene, 3-methyl-l-butene, 1-hexene, 4-methyl-l-pentene, 3-methyl-l-pentene, 3,4-dimethyl-l-pentene, 4-methyl-l-hexene, 3-ethyl-l-pentene, 3-ethyl-4-methyl-l-pentene, 3,4-dimethyl-l-hexene, 4-methyl-l-heptene, 3,4-dimethyl-l-heptene, 1-octene, 1-decene, 1-dodecene, 1-tetradecene, 1-hexadecene, 1-octadecene, or 1-eicosene, or the like can be given. Among these, from the viewpoint of the density range of the ethylene-based polymer (a2), it is preferable to use propylene and 1-butene.

[0051] Note that, in the aforementioned copolymer of ethylene and an α-olefin, it is more preferable that the amount of the structural unit derived from ethylene be 90 mol% or more, and further preferable that the amount of the structural unit derived from ethylene be 95 mol% or more. Also, in the aforementioned copolymer of ethylene and an α-olefin, it is more preferable that the amount of the structural unit derived from the α-olefin be 10 mol% or less, and further preferable that the amount of the structural unit derived from the α-olefin be 5 mol% or less. When the ethylene-based polymer (a2) is a copolymer of ethylene and an α-olefin, the more the amount of the structural unit derived from ethylene, the more preferable. Also, the ethylene-based polymer (a2) can be a wax.

[0052] [ETHYLENE-BASED POLYMER COMPOSITION (A)]

[0053] The content of the ultrahigh molecular weight ethylene-based polymer (al) in the ethylene-based polymer composition (A) is preferably 20 to 60 parts by mass, and more preferably 30 to 50 parts by mass (wherein the total amount of the ultrahigh molecular weight ethylene-based polymer (al) and the ethylene-based polymer (a2) is taken as 100 parts by mass).

[0054] The content of the ethylene-based polymer (a2) in the ethylene-based polymer composition (A) is preferably 40 to 80 parts by mass, and more preferably 50 to 70 parts by mass (wherein the total amount of the ultrahigh molecular weight ethylene-based polymer (al) and the ethylene-based polymer (a2) is taken as 100 parts by mass).

[0055] When the content of the ultrahigh molecular weight ethylene-based polymer (al) in the ethylene-based polymer composition (A) is 60 parts by mass or less and the content of the ethylene-based polymer (a2) is 40 parts by mass or more, the melt flowability of the ethylene-based polymer composition (A) can be made higher. Therefore, the moldability of the ethylene-based polymer composition (A) and the resin composition (X) containing the aforementioned ethylene-based polymer composition (A) easily becomes good. On the other hand, when the content of the ultrahigh molecular weight ethylene-based polymer (al) is 20 parts by mass or more and the content of the ethylene-based polymer (a2) is 80 parts by mass or less, the wear resistance derived from the ultrahigh molecular weight ethylene-based polymer (al) can be sufficiently obtained for the ethylene-based polymer composition (A) and the resin composition (X) containing the aforementioned ethylene-based polymer composition (A). As a result thereof, there is a tendency that the wear resistance of the ethylene-based polymer composition (A) and the resin composition (X) containing the aforementioned ethylene-based polymer composition (A) becomes good, and the wear resistance of a molded body obtained from the aforementioned resin composition (X) is excellent.

[0056] The ethylene-based polymer composition (A) preferably satisfies one or more of requirements (A-a) and (A-b).

[0057] [Requirement (A-a)]

[0058] The intrinsic viscosity [η] of the ethylene-based polymer composition (A) measured in a decahydronaphthalene solvent at 135°C is preferably 3.0 to 15 dl / g, more preferably 3.0 to 10 dl / g, and further preferably 5.0 to 10 dl / g. Details of the measuring method of the intrinsic viscosity [η] of the ethylene-based polymer composition (A) are described in the Examples.

[0059] When the intrinsic viscosity [η] in a decahydronaphthalene solvent at 135°C is 3.0 dl / g or more, the wear resistance of the ethylene-based polymer composition (A) and the resin composition (X) containing the aforementioned ethylene-based polymer composition (A) becomes good. As a result thereof, there is a tendency that the wear resistance of a molded body obtained from the resin composition (X) is excellent. On the other hand, when the intrinsic viscosity [η] in a decahydronaphthalene solvent at 135°C is 15 dl / g or less, the flowability of the ethylene-based polymer composition (A) does not decrease, and therefore the moldability of the resin composition (X) containing the ethylene-based polymer composition (A) easily becomes good. That is, when the intrinsic viscosity [η] of the ethylene-based polymer composition (A) in a decahydronaphthalene solvent at 135°C satisfies the aforementioned range, the resin composition (X) has a high melt flowability to the extent that the molding process becomes easy, and the wear resistance is also good.

[0060] [Requirement (A-b)]

[0061] The density of the ethylene-based polymer composition (A) is preferably 930 to 980 kg / m3 more preferably 940 to 980 kg / m 3 When the density of the ethylene-based polymer composition (A) is 930 kg / m 3 When the density of the ethylene-based polymer composition (A) is 930 kg / m 3 When the density of the ethylene-based polymer composition (A) is 930 kg / m

[0062] <Method for producing ethylene-based polymer composition (A)>

[0063] The method for producing the ethylene-based polymer composition (A) is not particularly limited as long as it is a method capable of containing the ultrahigh molecular weight ethylene-based polymer (al) and the ethylene-based polymer (a2) in predetermined proportions, and as a preferable method, the following methods (M-1) to (M-5) can be cited.

[0064] Method (M-1): A method produced by previously producing the ultrahigh molecular weight ethylene-based polymer (al) and the ethylene-based polymer (a2) in the presence of an olefin polymerization catalyst, and then blending these ultrahigh molecular weight ethylene-based polymer (al) and ethylene-based polymer (a2).

[0065] Method (M-2): A method produced in the presence of an olefin polymerization catalyst by a multistage polymerization method including at least two stages of a process of generating the ultrahigh molecular weight ethylene-based polymer (al) as a first process and a process of generating the ethylene-based polymer (a2) as a second process. Note that the second process is performed in the presence of the ultrahigh molecular weight ethylene-based polymer (al) generated in the first process.

[0066] Method (M-3): A method produced in the presence of an olefin polymerization catalyst by a multistage polymerization method including at least two stages of a process of generating the ethylene-based polymer (a2) as a first process and a process of generating the ultrahigh molecular weight ethylene-based polymer (al) as a second process. Note that the second process is performed in the presence of the ethylene-based polymer (a2) generated in the first process.

[0067] Method (M-4): A plurality of the ethylene-based polymer composition (A) obtained by the method (M-2) or the method (M-3) is blended.

[0068] Method (M-5): One or more selected from the group consisting of the ultra-high molecular weight ethylene-based polymer (al) and the ethylene-based polymer (a2) is blended with the ethylene-based polymer composition (A) obtained by the method (M-2), (M-3), (M-4).

[0069] In addition, the ultra-high molecular weight ethylene-based polymer (al) and the ethylene-based polymer (a2) can be produced, for example, by polymerizing monomers containing ethylene in the presence of a publicly known catalyst for olefin polymerization described in WO2008 / 013144, WO2010 / 074073 under polymerization conditions that make the ethylene-based polymer composition (A) have a desired property.

[0070] Among the methods (M-1) to (M-3), the methods (M-2) and (M-3) using a multistage polymerization method are more preferable, and the method (M-2) in which the ultra-high molecular weight ethylene-based polymer (al) is produced in the first step is further preferable. If a multistage polymerization method is used, the ultra-high molecular weight ethylene-based polymer (al) contained in the ethylene-based polymer composition (A) is compatible with the ethylene-based polymer (a2), and the dispersibility is improved, so that it is easy to balance the wear resistance and the moldability, and thus is preferable. In addition, from the aspect that the compatibility of the ultra-high molecular weight ethylene-based polymer (al) with the ethylene-based polymer (a2) is improved when a multistage polymerization method is used, the methods (M-4) and (M-5) are preferable compared to the method (M-1).

[0071] Further, when the method (M-2) is compared with the method (M-3), in the case where the ethylene-based polymer composition (A) is produced using the method (M-2), the addition of a chain transfer agent that causes a chain transfer reaction, the increase in the polymerization temperature, and the like are performed in the second step. Thereby, it is easy to adjust the molecular weight of the polymer (ethylene-based polymer (a2)) obtained in the second step to be lower than the molecular weight of the polymer (ultra-high molecular weight ethylene-based polymer (al)) obtained in the first step, and thus is preferable in terms of the production efficiency.

[0072] Note that, at this time, the olefin such as ethylene used in the polymerization can be various olefins described in the items of the ultra-high molecular weight ethylene-based polymer (al) and the ethylene-based polymer (a2) without limitation.

[0073] For the resin composition (X), the ethylene-based polymer composition (A), the ultrahigh molecular weight ethylene-based polymer (al) and the ethylene-based polymer (a2) (referred to as the resin composition and the polymer, etc. of one embodiment of the present application), as the raw material (for example, the monomer such as ethylene and α-olefin) thereof, only a raw material derived from biomass, only a raw material derived from fossil fuel, or both a raw material derived from biomass and a raw material derived from fossil fuel can be used.

[0074] The raw material derived from biomass refers to a raw material in which all (renewable) natural raw materials and residues thereof derived from plants or animals such as fungi, yeasts, algae, and bacteria are used as raw materials. For example, as carbon, a raw material containing carbon in a proportion of 1 x 10 -12 14 C isotope, a raw material in which the concentration of biomass carbon (unit: pMC) measured in accordance with ASTM D6866 is about 100 pMC. The raw material derived from biomass (for example, the monomer such as ethylene and α-olefin) can be obtained by a method known in the past, for example.

[0075] From the viewpoint of reducing environmental load (mainly, reducing greenhouse gases), it is preferable that the resin composition and the polymer, etc. of one embodiment of the present application contain a structural unit derived from a raw material derived from biomass.

[0076] As for the resin composition and the polymer, etc. of one embodiment of the present application, as long as the manufacturing conditions such as the polymerization catalyst, the polymerization process, the polymerization temperature, and the kneading method are the same, even the resin composition and the polymer, etc. containing a raw material derived from biomass contain carbon in a proportion of 1 x 10 -12 ～14 14 The molecular structure, the physical properties, and the like other than the C isotope are also the same as those of the resin composition and the polymer, etc. containing a raw material derived from fossil fuel. Thus, it is considered that the resin composition and the polymer, etc. containing a raw material derived from biomass have the same performance as the resin composition and the polymer, etc. containing a raw material derived from fossil fuel.

[0077] <Carbon-based filler (B)>

[0078] As the carbon-based filler (B) which is one of the components of the resin composition (X), for example, a carbon nanotube (CNT), a conductive carbon black (CB), and a carbon fiber can be given. As the carbon-based filler (B), these materials having conductivity are not particularly limited, and from the viewpoint of excellent effect of reducing the surface resistivity of a molded body, a carbon nanotube is preferable.

[0079] The carbon nanotube is a hollow fiber-like substance having a cylindrical shape formed of carbon, and can be either a multi-walled carbon nanotube or a single-walled carbon nanotube. ​​​

[0080] The average diameter of the carbon nanotube is preferably 1 nm or more, more preferably 5 nm or more, and further preferably 7 nm or more, and is preferably 20 nm or less. In addition, the average length of the carbon nanotube is preferably 0.5 μm or more, more preferably 0.6 μm or more, and is preferably 50 μm or less, more preferably 30 μm or less, and further preferably 15 μm or less. If the average diameter is 1 nm or more, there is a tendency that the carbon nanotube can not be easily cut during kneading, and if it is 20 nm or less, there is a tendency that the electrical conductivity can be improved. In addition, if the average length is 0.5 μm or more, there is a tendency that the electrical conductivity can be improved, and if it is 50 μm or less, there is a tendency that the viscosity during kneading can be suppressed from increasing, and the kneading and molding can be easily performed.

[0081] The average diameter and the average length of the carbon nanotube can be found by observing the carbon nanotube with an electron microscope (SEM, TEM) and performing an arithmetic average.

[0082] The carbon nanotube can be produced, for example, by an arc discharge method, a chemical vapor deposition method (CVD method), or a laser ablation method. A commercially available product of the carbon nanotube can also be used.

[0083] The carbon nanotube has a tendency to exhibit high electrical conductivity in a smaller amount, for example, as compared with carbon black, but is expensive, and thus it is advantageous from a cost viewpoint if it can be used in a smaller amount. In the present embodiment, by using the resin composition (X) containing the carbon-based filler (B) and the ethylene-based polymer composition (A), excellent electrical conductivity can be obtained. That is, in the resin composition (X), there is a tendency that high electrical conductivity can be obtained even with a small amount of the carbon nanotube.

[0084] As the conductive carbon black, for example, furnace black, ketjen black, channel black, lamp black, thermal black, and acetylene black can be given. Specifically, HAF-LS, HAF, HAF-HS, FEF, GPF, APF, SRF-LM, SRF-HM, and MT can be given.

[0085] The primary particle diameter of the conductive carbon black is preferably 0.005 μm or more, more preferably 0.01 μm or more, and is preferably 1 μm or less, and more preferably 0.2 μm or less. The primary particle diameter refers to a particle diameter obtained by performing a number average on a particle diameter (Heywood diameter: diameter of a circle having the same area as a projected area of a primary particle) measured with an electron microscope or the like.

[0086] As the carbon fiber, various carbon fibers known in the art can be used, and for example, carbon fibers produced from a polyacrylonitrile-based, a rayon-based, a pitch-based, a polyvinyl alcohol-based, a regenerated cellulose-based, and a mesophase pitch-based carbon fiber can be given. In terms of specific strength, the carbon fiber has an advantage in applications in which lightness and strength are valued, such as in aircrafts.

[0087] The carbon fiber can be a general-purpose fiber or a high-strength fiber. In addition, the carbon fiber can be a long fiber, a short fiber, a chopped fiber, or a recycled fiber.

[0088] As the binder (sizing agent) for the carbon fiber, for example, any one of a urethane-based emulsion, an epoxy-based emulsion, a nylon-based emulsion, or an olefin-based emulsion can be used.

[0089] The average length of the carbon fiber, that is, the average fiber length is preferably 0.1 mm or more, more preferably 0.3 mm or more, further preferably 0.5 mm or more, and preferably 15.0 mm or less, more preferably 13.0 mm or less. In the case where the average fiber length is 0.1 mm or more, there is a tendency that the reinforcing effect of the carbon fiber on the mechanical properties is sufficiently exhibited. In the case where the average fiber length is 15.0 mm or less, the dispersibility of the carbon fiber in the ethylene-based polymer composition (A) easily becomes good. As a result thereof, there is a tendency that the appearance of a molded body obtained by molding the resin composition (X) containing the ethylene-based polymer composition (A) and the carbon fiber becomes good.

[0090] The average diameter of the carbon fiber is preferably 3 μm or more, more preferably 5 μm or more, and preferably 30 μm or less, more preferably 21 μm or less, further preferably 19 μm or less. In the case where the average diameter of the carbon fiber is 3 μm or more, the carbon fiber is not easily broken during molding, and in addition, there is a tendency that the impact strength of the obtained molded body becomes high. In the case where the average diameter of the carbon fiber is 30 μm or less, the appearance of the molded body becomes good, and in addition, the aspect ratio of the carbon fiber is not reduced, and there is a tendency that the reinforcing effect on the mechanical properties such as the rigidity, heat resistance, and the like of the molded body obtained from the resin composition (X) is sufficiently exhibited.

[0091] The carbon-based filler (B) can be used in one kind or two or more kinds.

[0092] <Other Components>

[0093] The resin composition (X) can contain, within a range not impairing the object of the present application, a thermoplastic resin such as another polyolefin-based resin, and the like, a resin additive (for example, a stabilizer such as a heat-resistant stabilizer, a weather-resistant stabilizer, a crosslinking agent, a crosslinking co-agent, an antistatic agent, a slip agent, an antiblocking agent, an antifog agent, a lubricant, a dye, a pigment, a filler, a mineral oil-based softening agent, a petroleum resin, a wax other than the ethylene-based polymer (a2), and the like).

[0094] The total amount of the other components described above in the resin composition (X) is usually 5% by mass or less, preferably 2% by mass or less, and more preferably 1% by mass or less, when the other components are contained. In other words, the proportion of the total of the mass of the ultra-high molecular weight ethylene-based polymer (al), the mass of the ethylene-based polymer (a2), and the mass of the carbon-based filler (B) in the resin composition (X) is usually 95% by mass or more, preferably 98% by mass or more, and more preferably 99% by mass or more.

[0095] <ethylene-based resin composition (X)>

[0096] The resin composition (X) satisfies the requirements (X-a) and (X-b). It is preferable that the resin composition (X) satisfy the requirements (X-a) and (X-b), and satisfy one or more of the requirements (X-c) to (X-f).

[0097] [Requirement (X-a)]

[0098] The resin composition (X) contains 100 parts by mass of the aforementioned ethylene-based polymer composition (A) and 1 to 30 parts by mass of the carbon-based filler (B). The blending amount of the carbon-based filler (B) is preferably 5 to 25 parts by mass, and more preferably 5 to 15 parts by mass, relative to 100 parts by mass of the aforementioned ethylene-based polymer composition (A).

[0099] The resin composition (X) has high electrical conductivity because it contains the carbon-based filler (B) within the aforementioned range, and a molded body obtained from the resin composition (X) also has high electrical conductivity. In addition, the resin composition (X) has high sliding properties, wear resistance, rigidity, and chemical resistance because it contains the aforementioned ethylene-based polymer composition (A) within the aforementioned range, and a molded body obtained from the resin composition (X) also has sliding properties, wear resistance, rigidity, and chemical resistance.

[0100] [Requirement (X-b)]

[0101] The shear viscosity η of the resin composition (X) is measured at a temperature of 250°C and a shear rate of 1330 s -1 1330 The shear viscosity η of the resin composition (X) is measured at a temperature of 250°C and a shear rate of 1330 s -1 13.3 The ratio (η 1330 / η 13.3 ) of the shear viscosity η 1330 / η 13.3 ) is less than 0.027. The aforementioned ratio (η 1330 / η 13.3 ) is preferably 0.005 to 0.0265, more preferably 0.005 to 0.026, and further preferably 0.010 to 0.0255.

[0102] the aforementioned ratio (η 1330 / η 13.3 ) is within the aforementioned range, the wear resistance and the injection moldability of the resin composition (X) are easily balanced.

[0103] [Condition (X-c)]

[0104] The shear viscosity η -1 of the resin composition (X) is measured at a temperature of 250°C and a shear rate of 1330 s 1330 -1. It is preferably 100 to 300 Pa-s, more preferably 120 to 280 Pa-s, and further preferably 150 to 250 Pa-s. The shear rate applied to the molten resin when injection molding is sometimes a value closer to 1330 s -1 -1. Therefore, the aforementioned shear viscosity η 1330 can be said to be an index of the injection moldability of the resin composition (X) in the temperature region around 250°C. That is, when the aforementioned shear viscosity η 1330 of the resin composition (X) is within the aforementioned range, the injection moldability of the resin composition (X) in the temperature region around 250°C easily becomes easy.

[0105] [Condition (X-d)]

[0106] The shear viscosity η -1 of the resin composition (X) is measured at a temperature of 250°C and a shear rate of 13.3 s 13.3 -1. It is preferably 5000 to 20000 Pa-s, more preferably 5500 to 18000 Pa-s, and further preferably 6000 to 17000 Pa-s. When the MFR of the resin composition (X) of one embodiment of the present application is measured, there is a tendency that the shear rate applied to the molten resin is a value closer to 13.3 s -1 -1. Therefore, the aforementioned shear viscosity η 13.3 can be said to be an index of the MFR of the resin composition (X). That is, the higher the aforementioned shear viscosity η 13.3 , the more easily the MFR of the resin composition (X) becomes small. Therefore, if the aforementioned shear viscosity η 13.3 is within the aforementioned range, the MFR of the resin composition (X) easily decreases to the extent that the friction resistance is excellent.

[0107] [Condition (X-e)]

[0108] The MFR of the resin composition (X) measured at 190°C under a load of 10 kg in accordance with JIS K 7210-1:2014 is preferably 0.1 g / 10 minutes or less, more preferably less than 0.1 g / 10 minutes, further preferably 0.001 g / 10 minutes or more and less than 0.1 g / 10 minutes, and particularly preferably in the range of 0.005 to 0.09 g / 10 minutes.

[0109] When the MFR of the resin composition (X) is in the aforementioned range, there is a tendency for the wear resistance of the resin composition (X) to become good.

[0110] [Condition (X-f)]

[0111] The density of the resin composition (X) is preferably 990 to 1020 kg / m 3 , more preferably 995 to 1015 kg / m 3 . When the density of the resin composition (X) is 990 kg / m 3 or more, a molded body having excellent wear resistance can be obtained. In addition, when the density of the resin composition (X) is 1020 kg / m 3 or less, a molded body having excellent lightness can be obtained. Note that the method for measuring the density of the resin composition (X) is as described in the Examples.

[0112] Method for producing the ethylene-based resin composition (X)

[0113] The resin composition (X) can be obtained by a publicly known production method, for example, by dry mixing the ethylene-based polymer composition (A), the carbon-based filler (B), and the aforementioned other components as needed. In addition, after dry mixing, the resin composition (X) can be produced by melt-kneading with a single-screw or twin-screw extruder, extruding into strands, and pelletizing into granules. Note that the carbon-based filler (B) and the aforementioned other components can be mixed in advance with the polymer component such as the ethylene-based polymer composition (A) and added to the ethylene-based polymer composition (A) in the form of a master batch.

[0114] Molded body

[0115] The molded article of one embodiment of the present application contains the aforementioned resin composition (X). As a method for producing the molded article (i.e., a molding method of the resin composition (X)), specifically, there can be mentioned the molding methods of polyolefins known in the art, such as extrusion molding, injection molding, film molding, blow molding, blow molding, extrusion blow molding, injection blow molding, press molding, vacuum molding, powder condensation molding, calender molding, foaming molding, and the like. It is preferred that the aforementioned resin composition (X) be molded by injection molding to obtain a molded article containing the aforementioned resin composition (X). As the molded article, it is preferred that the molded article containing the resin composition (X) containing carbon nanotubes as the carbon-based filler (B) be used.

[0116] The aforementioned molded article can be a molded article formed of the resin composition (X), or a molded article having a portion, such as a surface layer, formed of the resin composition (X).

[0117] Generally, injection-molded articles have a tendency to have lower electrical conductivity (higher volume resistivity) than press-molded articles, but the molded article obtained by injection molding the resin composition (X) has a tendency to exhibit high electrical conductivity. That is, the resin composition (X) is capable of forming a molded article having excellent electrical conductivity regardless of the molding process.

[0118] For example, when an electrical conductivity test is performed on an injection-molded article obtained by injection molding the resin composition (X) at a processing temperature of 250°C and a mold temperature of 50°C (test temperature: 23°C, humidity: 50%, application time: 10 seconds, applied current: 0.1 to 1.0 mA), the volume resistivity is preferably 1 x 10 8 Ω·cm or less, more preferably 1 x 10 6 Ω·cm or less. The volume resistivity is more preferably smaller, but the lower limit is generally 1 x 10 1 Ω·cm.

[0119] Further, the mechanical properties of the molded article formed of the resin composition (X) are also excellent.

[0120] When a wear test is performed on the molded article obtained from the resin composition (X) (test temperature: 23°C, target material: S45C, speed: 50 cm / sec, sliding distance: 3 km, load: 15 kg), the specific wear amount (unit: 10 -3 mm 3 / (kgf·km). The specific wear amount is more preferably smaller, but the lower limit is generally 20 x 10 -3 mm 3or more. When the specific wear amount based on the abrasion test under the aforementioned conditions is in the aforementioned range, the wear resistance of the molded body obtained from the resin composition (X) is sufficient under the use environment of the molded body, and thus is preferably.

[0121]

[0122] As specific examples of the molded body, a wide range of uses from household goods such as daily necessities and leisure uses to general industrial uses and industrial goods can be mentioned. For example, home appliance material parts, communication equipment parts, electrical parts, electronic parts, automobile parts, parts of other vehicles, marine vessels, aircraft materials, mechanical mechanism parts, building material-related members, civil engineering members, agricultural materials, power tool parts, food containers, films, sheets, fibers can be mentioned.

[0123] In addition, the molded body of one embodiment of the present application can be widely used for the uses of polyethylene that have been known conventionally, and in particular, since the balance of wear resistance, self-lubricity, impact strength, thin-wall molding, and the like is excellent, the molded body can be used for uses requiring these, such as a coating material (lamination) of metal such as a steel pipe, an electric wire, a sliding door guide of an automobile, and the like, a coating material (lamination) of various rubbers such as a pressure-resistant rubber hose, a gasket for an automobile door, a gasket for a clean room door, a guide groove for an automobile glass, a sealing strip for an automobile, and the like, an inner liner for a hopper, a chute, and the like, a sliding material such as a gear, a bearing, a roller, a belt disc, various guides, an elevator guide, various protective gasket materials, and the like.

[0124] The molded body of one embodiment of the present application is excellent in conductivity, and thus can suppress electrification of various mechanical parts and sliding members, and can be suitably used for uses requiring antistatic properties.

[0125] Examples

[0126] Hereinafter, one embodiment of the present application will be described in more detail based on examples, but the present application is not limited to these examples.

[0127] [Measurement conditions of properties of polymers and polymer compositions]

[0128] Measurement conditions of each property are described below.

[0129] [Intrinsic viscosity [η]]

[0130] The intrinsic viscosity of the ethylene-based polymer composition (A) was measured at 135 °C in decalin, and was denoted as [η]. Similarly, the intrinsic viscosity of each of the ultrahigh molecular weight ethylene-based polymer (al) and the ethylene-based polymer (a2) was measured at 135 °C in decalin, and was denoted as [η].

[0131] [Measurement method of density]

[0132] ​The density of the ethylene-based polymer composition (A) before the addition of the carbon-based filler is measured according to ASTM D1505 using the density gradient method. The density of the ethylene-based polymer (a2) is also measured by the same method.

[0133] <Example 1>

[0134] In a 10 L reactor with a stirrer, in which nitrogen substitution was sufficiently performed, 4.0 L of refined hexane and 95 g of anhydrous magnesium chloride were added, and 350 ml of ethanol was added dropwise over 2 hours at room temperature with stirring, and mixed for about 1 hour at room temperature. Next, 330 ml of diethylaluminum chloride was added dropwise over 2 hours, and after the addition, mixed for about 1 hour at room temperature, and 1.3 L of titanium tetrachloride was added dropwise over 1 hour, and the reaction was performed at 80°C for 1 hour.

[0135] After the completion of the reaction, the solid part was separated using a filter, and the solid part was washed twice with refined hexane, and thereby a solid titanium catalyst component was obtained. The titanium content in the solid titanium catalyst component was 6.8% by weight, the magnesium content was 15% by weight, and the chlorine content was 60% by weight.

[0136] <Example 1>

[0137] [Manufacturing Example 1: Manufacturing of ethylene-based polymer composition (A-1)]

[0138] (First stage polymerization: Polymerization of ultra-high molecular weight ethylene-based polymer (al-1))

[0139] After 12 L of refined n-decane was added to a 24 L reaction vessel in which nitrogen substitution was sufficiently performed, the temperature was raised to 50°C. To the above reaction vessel, 12 mmol of triethylaluminum and a solid titanium catalyst component (0.12 mmol in terms of titanium atoms) prepared by Catalyst Preparation Example 1 were added at 50°C. Next, the catalyst inlet was closed, and the internal pressure of the reaction vessel was made 4.3 kg / cm 2 G, and the first stage polymerization was performed at 45 to 46°C. After 45 minutes of the introduction of ethylene, the pressure was released, and the temperature was lowered to normal temperature. The generated solid white polymer was partially separated and dried, and the intrinsic viscosity [η] was measured, and the result was 28.0 dl / g. Note that this value is the intrinsic viscosity [η] (135°C, decalin) of the ultra-high molecular weight ethylene-based polymer (al-1) contained in the ethylene-based polymer (A-1).

[0140] (Second stage polymerization: Polymerization of ethylene-based polymer (a2-1))

[0141] Next, 5.0 kg / cm 2 G of hydrogen was introduced into the reaction vessel, and further 3.0 kg / cm2 of ethylene, and the total pressure was made 8.0 kg / cm 2 • G, and the polymerization temperature was raised to 80°C, and the second stage polymerization (i.e., polymerization of ethylene-based polymer (a2-1)) was performed for 490 minutes. After cooling to normal temperature, the generated white polymer in solid form was separated and dried. The weight of the obtained ethylene-based polymer composition (A-1) was 3460 g, the intrinsic viscosity [η] (135°C in decalin) of the ethylene-based polymer composition (A-1) was 7.4 dl / g, and the density was 966 kg / m 3 .

[0142] (Measurement of the properties of ethylene-based polymer (a2-1))

[0143] The polymerization was additionally performed under the conditions of the second stage, and the generated white polymer in solid form was separated and dried. The weight of the obtained ethylene-based polymer (a2-1') was 2162 g, the intrinsic viscosity [η] (135°C in decalin) was 1.1 dl / g, and the density was 970 kg / m 3 Here, the ethylene-based polymer (a2-1') corresponds to the polymer generated in the second stage polymerization of the ethylene-based polymer composition (A-1), and thus the intrinsic viscosity, the density, and the generated amount of the ethylene-based polymer (a2-1') are the same as those of the ethylene-based polymer (a2-1).

[0144] (Content of ultrahigh molecular weight ethylene-based polymer (a1-1))

[0145] The difference between the generated amount of the obtained ethylene-based polymer composition (A-1) and the generated amount of the ethylene-based polymer (a2-1') was taken as the generated amount of the ultrahigh molecular weight ethylene-based polymer (a1-1), and further, the content of the ultrahigh molecular weight ethylene-based polymer (a1-1) in the ethylene-based polymer composition (A-1) was calculated from the mass ratio of the polymers to be 38 mass%.

[0146] [Production of master batch (C1) containing carbon-based filler (B-1)]

[0147] As the carbon-based filler (B-1), carbon nanotube (manufactured by Nanocyl, trade name: carbon nanotube NC7000, average diameter: 9.5 nm, average length: 1.5 μm) was used.

[0148] The carbon-based filler (B-1) 15 mass% and the ethylene-based polymer composition (A-1) obtained in Production Example 1 85 mass% were kneaded with a twin-screw extruder to produce a master batch (C1). As to the kneading conditions, the temperature was 250°C, the diameter of the extruder was 30 mm, and L / D = 30.

[0149] [Preparation Example 1: Production of Ethylene-based Resin Composition (X-1)]

[0150] The ethylene-based polymer composition (A-1) obtained in Production Example 1, 40 mass%, and the master batch (C1), 60 mass%, were mixed, and kneaded with a twin-screw extruder to produce the ethylene-based resin composition (X-1). As to the kneading conditions, the temperature was 250°C, the diameter of the extruder was 30 mm, and L / D = 30. After the kneading treatment, the ethylene-based resin composition (X-1) was extruded into a strand shape and pelletized into pellets. Further, the pellets obtained were used to measure various physical properties.

[0151] [Measurement of MFR (Melt Flow Rate)]

[0152] The MFR of the ethylene-based resin composition (X-1) was measured in accordance with JIS K7210-1:2014 at a measurement temperature of 190°C under a load of 10 kg. The results obtained are shown in Table 1-1. Note that in the following description, Table 1-1 and Table 1-2 are collectively referred to as Table 1.

[0153] [Measurement of Density of Ethylene-based Resin Composition (X-1)]

[0154] The density of the ethylene-based resin composition (X-1) was measured in the same manner as the ethylene-based resin composition (A) by the density gradient method in accordance with ASTM D1505. The results obtained are shown in Table 1.

[0155] [Measurement of Shear Viscosity]

[0156] The shear viscosity of the ethylene-based resin composition (X-1) was measured using a capillary rheometer, Capilograph 1D, manufactured by Toyo Seiki Jidoka K.K. The conditions were set to a resin temperature of 250°C, a preheating time of 6 minutes, a cylinder diameter of Φ 10 mm, and the shear viscosity was measured at a shear rate of 13.3 sec -1 , 1330 sec -1 . The results obtained are shown in Table 1.

[0157] [Production of Injection Molded Body]

[0158] The pellets of the ethylene-based resin composition (X-1) were injection molded using a full-automatic injection molding machine, EC75SX-III, manufactured by Shibaura Machine Co., Ltd., under conditions of a processing temperature of 250°C and a mold temperature of 50°C to obtain a square plate of 120 x 130 x 3 mm.

[0159] [Measurement of Volume Resistivity]

[0160] An injection-molded body (120 x 130 x 3 mm) of the ethylene-based resin composition (X-1) was measured in accordance with JIS K7194; 1994, using a Loresta GX-MCP-T700 low resistivity meter manufactured by Hitachi Instruments Service Co., Ltd., under conditions of an application time of 10 seconds, a temperature of 23°C, a humidity of 50%, and an application current of 0.1 to 1.0 mA. The results obtained are shown in Table 1.

[0161] [Measurement of Specific Wear Volume]

[0162] An injection-molded body (120 x 130 x 3 mm) of the ethylene-based resin composition (X-1) was punched into a 30 x 30 x 3 mm piece using a Schopper sample punch manufactured by Ushio Manufacturing Co., Ltd. The 30 x 30 x 3 mm punched piece was measured in accordance with JIS K7218, using a friction and wear tester EFM-3 manufactured by A&D Company, Ltd. The conditions were set to be a subject material S45C, a speed of 50 cm / sec, a distance of 3 km, a load of 15 kg, and a temperature of 23°C. The results obtained are shown in Table 1.

[0163] [Example 2]

[0164] [Production Example 2: Production of Ethylene-Based Polymer Composition (A-2)]

[0165] The first-stage polymerization, the second-stage polymerization, and the measurement were performed under the same conditions as in Production Example 1, except that the pressure inside the first-stage reaction vessel was set to 4.6 kg / cm 2 G. The resulting solid white polymer was separated and dried. The weight of the ethylene-based polymer composition (A-2) obtained was 3550 g, the intrinsic viscosity [η] (135°C in decalin) of the ethylene-based polymer composition (A-2) was 8.3 dl / g, and the density was 966 kg / m 3 . In addition, the intrinsic viscosity [η] of the solid white polymer produced in the first stage (i.e., the intrinsic viscosity of the ultra-high molecular weight ethylene-based polymer (a1-2), 135°C in decalin) was 28.0 dl / g.

[0166] The polymerization was performed under the same conditions as in Production Example 1, except that the pressure inside the first-stage reaction vessel was set to 4.6 kg / cm 3 . In addition, the intrinsic viscosity [η] of the solid white polymer produced in the first stage (i.e., the intrinsic viscosity of the ultra-high molecular weight ethylene-based polymer (a1-2), 135°C in decalin) was 28.0 dl / g.

[0167] The content of the ultra-high molecular weight ethylene-based polymer (al-2) in the ethylene-based polymer composition (A-2) was 39 mass% calculated from the mass ratio of the polymers.

[0168] [Production of master batch (C2) containing carbon-based filler (B-1)]

[0169] Master batch (C2) was produced in the same manner as the production of master batch (Cl) except that ethylene-based polymer composition (A-2) was used instead of ethylene-based polymer composition (Al).

[0170] [Preparation Example 2: Production of ethylene-based resin composition (X-2)]

[0171] The composition was produced in the same manner as in Example 1 except that ethylene-based polymer composition (A-2) 40 mass% and master batch (C2) 60 mass% were used, and the production of injection-molded bodies and the measurement of various properties were performed. The results are shown in Table 1.

[0172] [Example 3]

[0173] [Preparation Example 3: Production of ethylene-based polymer composition (A-3)]

[0174] The first-stage reaction vessel was pressurized to 4.1 kg / cm 2 G, and the first-stage polymerization, the second-stage polymerization, and the measurement were performed under the same conditions as in Preparation Example 1. The resulting solid white polymer was separated and dried. The weight of the obtained ethylene-based polymer composition (A-3) was 3650 g, the intrinsic viscosity [η] (135°C in decalin) of the ethylene-based polymer composition (A-3) was 6.9 dl / g, and the density was 966 kg / m 3 . In addition, the intrinsic viscosity [η] of the solid white polymer produced in the first stage (i.e., the intrinsic viscosity of the ultra-high molecular weight ethylene-based polymer (al-3), 135°C in decalin) was 28.0 dl / g.

[0175] In addition, the polymerization was performed under the conditions of the second stage, and the resulting solid white polymer was separated and dried. The weight of the obtained ethylene-based polymer (a2-3') was 2313 g, the intrinsic viscosity [η] (135°C in decalin) was 1.1 dl / g, and the density was 970 kg / m 3 . Note that the intrinsic viscosity, the density, and the amount of production of the ethylene-based polymer (a2-3') were the same as those of the ethylene-based polymer (a2-3) contained in the ethylene-based polymer composition (A-3).

[0176] The content of the ultra-high molecular weight ethylene-based polymer (al-3) in the ethylene-based polymer composition (A-3) was calculated from the mass ratio of the polymers to be 37 mass %.

[0177] [Production of master batch (C3) containing carbon-based filler (B-1)]

[0178] Master batch (C3) was produced in the same manner as the production of master batch (Cl) except that ethylene-based polymer composition (A-3) was used instead of ethylene-based polymer composition (Al).

[0179] [Preparation Example 3: Production of ethylene-based resin composition (X-3)]

[0180] The composition was produced in the same manner as in Example 1 except that ethylene-based polymer composition (A-3) 40 mass % and master batch (C3) 60 mass % were used, and the production of injection-molded bodies and the measurement of various properties were performed. The results are shown in Table 1.

[0181] [Example 4]

[0182] [Production Example 4: Production of ethylene-based polymer composition (A-4)]

[0183] The first-stage polymerization, the second-stage polymerization, and the measurement were performed under the same conditions as in Production Example 1 except that the internal pressure of the first-stage reaction vessel was made to be 3.6 kg / cm 2 G. The obtained ethylene-based polymer composition (A-4) weighed 3170 g, the intrinsic viscosity [η] (135°C in decalin) of the ethylene-based polymer composition (A-4) was 5.2 dl / g, and the density was 967 kg / m 3 . In addition, the intrinsic viscosity [η] of the solid white polymer produced in the first stage (i.e., the intrinsic viscosity of the ultra-high molecular weight ethylene-based polymer (al-4), 135°C in decalin) was 28.0 dl / g.

[0184] In addition, the polymerization was performed under the conditions of the second stage, and the obtained solid white polymer was separated and dried. The obtained ethylene-based polymer (a2-4') weighed 2148 g, the intrinsic viscosity [η] (135°C in decalin) was 1.1 dl / g, and the density was 970 kg / m 3 . Note that the intrinsic viscosity, the density, and the amount of production of the ethylene-based polymer (a2-4') were the same as those of the ethylene-based polymer (a2-4) contained in the ethylene-based polymer composition (A-4).

[0185] The content of the ultra-high molecular weight ethylene-based polymer (al-4) in the ethylene-based polymer composition (A-4) was 32% by mass, calculated from the mass ratio of the polymers.

[0186] [Production of master batch (C4) containing carbon-based filler (B-1)]

[0187] Master batch (C4) was produced in the same manner as the production of master batch (Cl), except that ethylene-based polymer composition (A-4) was used instead of ethylene-based polymer composition (Al).

[0188] [Preparation Example 4: Production of ethylene-based resin composition (X-4)]

[0189] The composition was produced in the same manner as in Example 1, except that 40% by mass of ethylene-based polymer composition (A-4) and 60% by mass of master batch (C4) were used, and the production of injection-molded bodies and the measurement of various properties were performed. The results are shown in Table 1.

[0190] [Example 5]

[0191] [Production Example 5: Production of ethylene-based polymer composition (A-5)]

[0192] The first-stage reaction vessel was pressurized to 5.0 kg / cm 2 G, and the first-stage polymerization, the second-stage polymerization, and the measurement were performed under the same conditions as in Production Example 1. The resulting solid white polymer was separated and dried. The weight of the obtained ethylene-based polymer composition (A-5) was 3660 g, the intrinsic viscosity [η] of the ethylene-based polymer composition (A-5) (135°C, decalin) was 9.3 dl / g, and the density was 965 kg / m 3 . In addition, the intrinsic viscosity [η] of the solid white polymer produced in the first stage (i.e., the intrinsic viscosity of the ultra-high molecular weight ethylene-based polymer (al-5), 135°C, decalin) was 28.0 dl / g.

[0193] In addition, the polymerization was performed under the conditions of the second stage, and the resulting solid white polymer was separated and dried. The weight of the obtained ethylene-based polymer (a2-5') was 2158 g, the intrinsic viscosity [η] (135°C, decalin) was 1.1 dl / g, and the density was 970 kg / m 3 . Note that the intrinsic viscosity, the density, and the amount of production of the ethylene-based polymer (a2-5') were the same as those of the ethylene-based polymer (a2-5) contained in the ethylene-based polymer composition (A-5).

[0194] The content of the ultra-high molecular weight ethylene-based polymer (al-5) in the ethylene-based polymer composition (A-5) was 41 mass% calculated from the mass ratio of the polymers.

[0195] [Production of master batch (C5) containing carbon-based filler (B-1)]

[0196] Master batch (C5) was produced in the same manner as the production of master batch (Cl) except that ethylene-based polymer composition (A-5) was used instead of ethylene-based polymer composition (A-l).

[0197] [Preparation Example 5: Production of ethylene-based resin composition (X-5)]

[0198] The composition was produced in the same manner as in Example 1 except that ethylene-based polymer composition (A-5) 40 mass% and master batch (C5) 60 mass% were used, and the production of injection-molded bodies and the measurement of various properties were performed. The results are shown in Table 1.

[0199] [Comparative Example 1]

[0200] [Preparation Example 6: Production of ethylene-based polymer composition (A-6)]

[0201] The first-stage reaction vessel was pressurized to 3.2 kg / cm 2 G, and the first-stage polymerization, the second-stage polymerization, and the measurement were performed under the same conditions as in Preparation Example 1. The resulting solid white polymer was separated and dried. The weight of the obtained ethylene-based polymer composition (A-6) was 3380 g, the intrinsic viscosity [η] (135°C in decalin) of the ethylene-based polymer composition (A-6) was 4.3 dl / g, and the density was 969 kg / m 3 . In addition, the intrinsic viscosity [η] of the solid white polymer produced in the first stage (i.e., the intrinsic viscosity of the ultra-high molecular weight ethylene-based polymer (al-6), 135°C in decalin) was 28.0 dl / g.

[0202] In addition, the polymerization was performed under the conditions of the second stage, and the resulting solid white polymer was separated and dried. The weight of the obtained ethylene-based polymer (a2-6') was 2468 g, the intrinsic viscosity [η] (135°C in decalin) was 1.1 dl / g, and the density was 970 kg / m 3 . Note that the intrinsic viscosity, the density, and the amount of production of the ethylene-based polymer (a2-6') were the same as those of the ethylene-based polymer (a2-6) contained in the ethylene-based polymer composition (A-6).

[0203] The content of the ultra-high molecular weight ethylene-based polymer (al-6) in the ethylene-based polymer composition (A-6) was 27 mass% calculated from the mass ratio of the polymers.

[0204] [Production of master batch (C6) containing carbon-based filler (B-1)]

[0205] The master batch (C6) was produced in the same manner as the production of the master batch (Cl) except that the ethylene-based polymer composition (A-6) was used instead of the ethylene-based polymer composition (Al).

[0206] [Preparation Example 6: Production of ethylene-based resin composition (CX-6)]

[0207] The composition was produced in the same manner as in Example 1 except that the ethylene-based polymer composition (A-6) 40 mass% and the master batch (C6) 60 mass% were used, and the production of the injection-molded body and the measurement of various properties were performed. The results are shown in Table 1.

[0208] [Comparative Example 2]

[0209] [Production Example 7: Production of ethylene-based polymer composition (A-7)]

[0210] The first-stage reaction vessel was pressurized to 2.9 kg / cm 2 G, and the first-stage polymerization, the second-stage polymerization, and the measurement were performed under the same conditions as in the Production Example 1. The white solid polymer produced was separated and dried. The weight of the ethylene-based polymer composition (A-7) obtained was 3220 g, the intrinsic viscosity [η] (135°C in decalin) of the ethylene-based polymer composition (A-7) was 3.5 dl / g, and the density was 969 kg / m 3 . In addition, the intrinsic viscosity [η] of the white solid polymer produced in the first stage (i.e., the intrinsic viscosity of the ultra-high molecular weight ethylene-based polymer (al-7), 135°C in decalin) was 28.0 dl / g.

[0211] The polymerization was performed under the conditions of the second stage additionally, and the white solid polymer produced was separated and dried. The weight of the ethylene-based polymer (a2-7') obtained was 2394 g, the intrinsic viscosity [η] (135°C in decalin) was 1.1 dl / g, and the density was 970 kg / m 3 . Note that the intrinsic viscosity, the density, and the production amount of the ethylene-based polymer (a2-7') were the same as those of the ethylene-based polymer (a2-7) contained in the ethylene-based polymer composition (A-7).

[0212] The content of the ultra-high molecular weight ethylene-based polymer (al-7) in the ethylene-based polymer composition (A-7) was 26 mass% calculated from the mass ratio of the polymers.

[0213] [Production of master batch (C7) containing carbon-based filler (B-1)]

[0214] Master batch (C7) was produced in the same manner as the production of master batch (Cl) except that ethylene-based polymer composition (A-7) was used instead of ethylene-based polymer composition (A-l).

[0215] [Preparation Example 7: Production of ethylene-based resin composition (CX-7)]

[0216] The composition was produced in the same manner as Example 1 except that ethylene-based polymer composition (A-7) 40 mass% and master batch (C7) 60 mass% were used, and the production of injection-molded bodies and the measurement of various properties were performed. The results are shown in Table 1.

[0217] [Comparative Example 3]

[0218] [Production Example 8: Production of ethylene-based polymer composition (A-8)]

[0219] The pressure in the reaction vessel in the first stage was made 2.5 kg / cm 2 G, and the first-stage polymerization, the second-stage polymerization, and the measurement were performed under the same conditions as Production Example 1. The white solid polymer produced was separated and dried. The weight of the ethylene-based polymer composition (A-8) obtained was 3300 g, the intrinsic viscosity [η] (135°C in decalin) of the ethylene-based polymer composition (A-8) was 2.4 dl / g, and the density was 969 kg / m 3 . In addition, the intrinsic viscosity [η] of the white solid polymer produced in the first stage (i.e., the intrinsic viscosity of the ultra-high molecular weight ethylene-based polymer (al-8), 135°C in decalin) was 28.0 dl / g.

[0220] In addition, polymerization was performed under the conditions of the second stage, and the white solid polymer produced was separated and dried. The ethylene-based polymer (a2-8') obtained had a weight of 2526 g, an intrinsic viscosity [η] (135°C in decalin) of 1.1 dl / g, and a density of 970 kg / m 3 . Note that the intrinsic viscosity, the density, and the amount produced of the ethylene-based polymer (a2-8') were the same as those of the ethylene-based polymer (a2-8) contained in the ethylene-based polymer composition (A-8).

[0221] The content of the ultra-high molecular weight ethylene-based polymer (al-8) in the ethylene-based polymer composition (A-8) was 23 mass% calculated from the mass ratio of the polymers.

[0222] [Production of master batch (C8) containing carbon-based filler (B-1)]

[0223] Master batch (C8) was produced in the same manner as the production of master batch (Cl) except that ethylene-based polymer composition (A-8) was used instead of ethylene-based polymer composition (A-l).

[0224] [Preparation Example 8: Production of ethylene-based resin composition (CX-8)]

[0225] The composition was produced in the same manner as Example 1 except that ethylene-based polymer composition (A-8) 40 mass% and master batch (C8) 60 mass% were used, and the production of injection-molded bodies and the measurement of various properties were performed. The results are shown in Table 1.

[0226] [Comparative Example 4]

[0227] [Production Example 9: Production of ethylene-based polymer composition (A-9)]

[0228] The first-stage reaction vessel was pressurized to 3.4 kg / cm 2 G, and the first-stage polymerization, the second-stage polymerization, and the measurement were performed under the same conditions as Production Example 1. The resulting solid white polymer was separated and dried. The weight of the obtained ethylene-based polymer composition (A-9) was 3160 g, the intrinsic viscosity [η] (135°C in decalin) of the ethylene-based polymer composition (A-9) was 4.8 dl / g, and the density was 968 kg / m 3 . In addition, the intrinsic viscosity [η] of the solid white polymer produced in the first stage (i.e., the intrinsic viscosity of the ultra-high molecular weight ethylene-based polymer (al-9), 135°C in decalin) was 28.0 dl / g.

[0229] In addition, the polymerization was performed under the conditions of the second stage, and the resulting solid white polymer was separated and dried. The weight of the obtained ethylene-based polymer (a2-9') was 2224 g, the intrinsic viscosity [η] (135°C in decalin) was 1.1 dl / g, and the density was 970 kg / m 3 . Note that the intrinsic viscosity, the density, and the amount of production of the ethylene-based polymer (a2-9') were the same as those of the ethylene-based polymer (a2-9) contained in the ethylene-based polymer composition (A-9).

[0230] The content of the ultra-high molecular weight ethylene-based polymer (al-9) in the ethylene-based polymer composition (A-9) was 30% by mass, calculated from the mass ratio of the polymers.

[0231] [Production of master batch (C9) containing carbon-based filler (B-1)]

[0232] Master batch (C9) was produced in the same manner as the production of master batch (Cl) except that ethylene-based polymer composition (A-9) was used instead of ethylene-based polymer composition (Al) and the kneading temperature was set to 270°C.

[0233] [Preparation Example 9: Production of ethylene-based resin composition (CX-9)]

[0234] The composition was produced in the same manner as Example 1 except that ethylene-based polymer composition (A-2) 40% by mass and master batch (C9) 60% by mass were used, and the production of injection-molded bodies and the measurement of various properties were performed. The results are shown in Table 1.

[0235] [Comparative Example 5]

[0236] [Production Example 10: Production of ethylene-based polymer composition (A-10)]

[0237] The first-stage reaction vessel internal pressure was set to 3.3 kg / cm 2 G, and the first-stage polymerization, the second-stage polymerization, and the measurement were performed under the same conditions as Production Example 1. The resulting solid white polymer was separated and dried. The weight of the obtained ethylene-based polymer composition (A-10) was 3400 g, the intrinsic viscosity [η] (135°C, decalin) of the ethylene-based polymer composition (A-10) was 4.7 dl / g, and the density was 968 kg / m 3 . In addition, the intrinsic viscosity [η] of the solid white polymer produced in the first stage (i.e., the intrinsic viscosity of the ultra-high molecular weight ethylene-based polymer (al-10), 135°C, decalin) was 28.0 dl / g.

[0238] In addition, the polymerization was performed under the conditions of the second stage, and the resulting solid white polymer was separated and dried. The weight of the obtained ethylene-based polymer (a2-10') was 2438 g, the intrinsic viscosity [η] (135°C, decalin) was 1.1 dl / g, and the density was 970 kg / m 3 . Note that the intrinsic viscosity, the density, and the production amount of the ethylene-based polymer (a2-10') were the same as those of the ethylene-based polymer (a2-10) contained in the ethylene-based polymer composition (A-10).

[0239] The content of the ultrahigh molecular weight ethylene-based polymer (al-10) in the ethylene-based polymer composition (A-10) was 28% by mass, calculated from the mass ratio of the polymers.

[0240] [Production of master batch (C10) containing carbon-based filler (B-1)]

[0241] Master batch (C10) was produced in the same manner as the production of master batch (C1), except that ethylene-based polymer composition (A-10) was used instead of ethylene-based polymer composition (A-1).

[0242] [Preparation Example 10: Production of ethylene-based resin composition (CX-10)]

[0243] Composition was produced in the same manner as Example 1, except that ethylene-based polymer composition (A-10) 40% by mass and master batch (C10) 60% by mass were used, and production of injection-molded bodies and measurement of various properties were performed. The results are shown in Table 1.

[0244] [Comparative Example 6]

[0245] [Production Example 11: Production of ethylene-based polymer composition (A-11)]

[0246] Ethylene-based polymer composition (A-11') having an intrinsic viscosity [η] of 4.4 dl / g (135°C, decalin) was produced by second-stage polymerization in a mass ratio of 41 / 59 of ultrahigh molecular weight ethylene-based polymer (al-11) having an intrinsic viscosity [η] of 30 dl / g (135°C, decalin) and ethylene-based polymer (a2-11-1) having an intrinsic viscosity [η] of 1.5 dl / g (135°C, decalin). Subsequently, ethylene-based polymer composition (A-11') was melt-blended with ethylene-based polymer (a2-11-2) having an intrinsic viscosity [η] of 1.1 dl / g (135°C, decalin) and a density of 965 kg / m 3

[0247] [Production of master batch (C11) containing carbon-based filler (B-1)]

[0248] Master batch (C11) was produced in the same manner as the production of master batch (C1), except that ethylene-based polymer composition (A-11) 75% by mass was used instead of ethylene-based polymer composition (A-1), and 10% by mass of wax (polyethylene wax, corresponding to ethylene-based polymer (a2)) was additionally used.​

[0249] [Preparation Example 11: Production of ethylene-based resin composition (CX-11)]

[0250] The composition was produced in the same manner as in Example 1 except that ethylene-based polymer composition (A-11) 40 mass% and master batch (C11) 60 mass% were used, and production of an injection-molded body and measurement of various properties were performed. The results are shown in Table 1.

[0251] [Table 1-1]

[0252]

[0253] [Table 1-2]

[0254]

Claims

1. An ethylene-based resin composition (X) containing 100 parts by mass of an ethylene-based polymer composition (A) and 1 to 30 parts by mass of a carbon-based filler (B), at a temperature of 250°C and a shear rate of 1330 s -1 The shear viscosity η determined below 1330 at a temperature of 250°C and a shear rate of 13.3 s -1 The shear viscosity η determined below 13.3 The ratio η 1330 / η 13.3 is less than 0.

027.

2. The ethylene-based resin composition (X) according to claim 1, wherein, the carbon-based filler (B) is a carbon nanotube.

3. The ethylene-based resin composition (X) according to claim 1, wherein, In the ethylene-based polymer composition (A), the total amount of an ultrahigh molecular weight ethylene-based polymer (al) having an intrinsic viscosity [η] of 10 to 40 dl / g measured in decalin at 135°C and a low or high molecular weight ethylene-based polymer (a2) having an intrinsic viscosity [η] of 0.1 to 9 dl / g measured in decalin at 135°C is 100 parts by mass, the content of the ultrahigh molecular weight ethylene-based polymer (al) is 20 to 60 parts by mass, and the content of the low or high molecular weight ethylene-based polymer (a2) is 40 to 80 parts by mass.

4. The ethylene-based resin composition (X) according to claim 1, wherein, The melt flow rate under a load of 190°C, 10 kg is 0.1 g / 10 minutes or less.

5. The ethylene-based resin composition (X) according to claim 1, wherein, The ethylene-based polymer composition (A) has an intrinsic viscosity [η] of 3.0 to 15 dl / g measured in decalin at 135°C, and a density of 930 to 980 kg / m3 3 .

6. A molded body comprising the ethylene-based resin composition (X) according to any one of claims 1 to 5.

7. The molded body according to claim 6, which is an injection-molded body.

8. The molded body according to claim 6, which is a coating material or a sliding material.

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