Copolymer composition for conveyor belts, laminate and industrial belt

Abstract

Provided is a copolymer composition for conveyor belts that can give a laminate having excellent adhesion to a layer containing a fiber material and an excellent balance between heat aging resistance and abrasion resistance. [Solution] The present invention provides a copolymer composition for conveyor belts, which comprises an ethylene-α-olefin-non-conjugated polyene copolymer (L-1) having structural units derived from ethylene (A), structural units derived from an α-olefin (B) having 4 to 20 carbon atoms, and structural units derived from a non-conjugated polyene (C) having, in one molecule, two or more partial structures selected from the group consisting of the following general formulas (I) and (II): an ethylene-α-olefin copolymer (L-2) having structural units derived from ethylene and structural units derived from an α-olefin having 3 to 20 carbon atoms, and trans-polyoctenylene (M); a laminate comprising a layer containing the copolymer composition; and an industrial belt comprising the laminate. JPEG2026043484000008.jpg28170

Description

[Technical Field]

[0001] The present invention relates to a copolymer composition for conveyor belts, a laminate, and an industrial belt. [Background technology]

[0002] In various industrial fields such as iron and steel, coal, and cement, belt conveyors are used as a means of transporting goods, and in particular, there are many cases where high-temperature goods such as clinker, which have a temperature of about 150 to 250°C, are transported by belt conveyors. The conveyor belts (sometimes referred to as "conveyor belts") used in belt conveyors transport iron ore and high-temperature coke, and therefore are required to have heat aging resistance and abrasion resistance in order to minimize maintenance work and extend the service life.

[0003] As a copolymer composition for conveyor belts that has excellent processability, mechanical properties, heat aging resistance, and abrasion resistance, a copolymer composition for conveyor belts that contains an ethylene-α-olefin-non-conjugated polyene copolymer; (F) an ethylene-α-olefin copolymer containing ethylene and an α-olefin having 3 to 20 carbon atoms; (G) carbon black; and (H) an antioxidant has been disclosed (see, for example, Patent Document 1). Also, as an ethylene-based copolymer composition that has excellent adhesion to a layer containing a fibrous material and can maintain the mechanical properties of the resulting laminate, an ethylene-α-olefin-non-conjugated polyene copolymer that satisfies specific requirements and contains (M) trans-polyoctenylene has been disclosed (see, for example, Patent Document 2). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2022-147453 [Patent Document 2] Japanese Patent Application Publication No. 2023-23924 Summary of the Invention [Problem to be solved by the invention]

[0005] The layer structure of a conveyor belt is generally cover layer / carcass layer / canvas / ... / inner cover layer. Since the cover layer comes into direct contact with the transported material, it is required to have heat aging resistance and abrasion resistance. On the other hand, the physical properties required for the carcass layer include adhesion to the canvas (tackiness and peel strength). Due to the differences in the required properties of the cover layer and the carcass layer, suitable materials are used for each layer. To facilitate easier management of the conveyor belt manufacturing process, there is a demand for the development of a material that can serve as both of these layers in one material, that is, a material that can integrate the cover layer and carcass layer.

[0006] An object of one embodiment of the present invention is to provide a copolymer composition for a conveyor belt that has excellent adhesion to a layer containing a fiber material and that can give a laminate having an excellent balance of heat aging resistance and abrasion resistance. Another problem to be solved by one embodiment of the present invention is to provide a laminate and an industrial belt that have an excellent balance between heat aging resistance and abrasion resistance. [Means for solving the problem]

[0007] The means for solving the above problems include the following aspects. <1> an ethylene-α-olefin-non-conjugated polyene copolymer (L-1) having a structural unit derived from ethylene (A), a structural unit derived from an α-olefin (B) having 4 to 20 carbon atoms, and a structural unit derived from a non-conjugated polyene (C) containing, in one molecule, two or more partial structures selected from the group consisting of the following general formulas (I) and (II): an ethylene-α-olefin copolymer (L-2) other than the copolymer (L-1) containing structural units derived from ethylene and structural units derived from an α-olefin having 3 to 20 carbon atoms; trans polyoctenylene (M), 1. A copolymer composition for a conveyor belt, comprising:

[0008] [ka]

[0009] <2> The ethylene-α-olefin-non-conjugated polyene copolymer (L-1) satisfies the following requirements (1) to (3): <1> The copolymer composition for a conveyor belt according to claim 1. Requirement (1): The ratio [A] / [B] of the number of moles of structural units derived from ethylene (A) to the number of moles [B] of structural units derived from an α-olefin having 4 to 20 carbon atoms is 40 / 60 to 90 / 10; Requirement (2): The content ratio of the number of moles [C] of the structural units derived from the non-conjugated polyene (C) is 0.1 to 6.0 mol % relative to 100 mol % in total of the [A], the [B], and the [C]; Requirement (3): The B value represented by the following formula (i) is 1.20 or more. B value = ([EX] + 2[Y]) / (2 × [E] × ([X] + [Y])) ... Formula (i) [Here, [E], [X], and [Y] represent the molar fractions of structural units derived from ethylene [A], α-olefin [B] having 4 to 20 carbon atoms, and non-conjugated polyene [C], respectively, and [EX] represents the ethylene [A]-α-olefin [B] having 4 to 20 carbon atoms dyad chain fraction.] <3> the structural unit derived from the α-olefin (B) having 4 to 20 carbon atoms is a structural unit derived from 1-butene; <1> or <2> The copolymer composition for a conveyor belt according to claim 1. <4> The structural unit derived from the non-conjugated polyene (C) is a structural unit derived from 5-vinyl-2-norbornene (VNB). <1> ~ <3> 10. The copolymer composition for a conveyor belt according to claim 9, wherein the copolymer composition is a copolymer of a hydroxybenzoate and a hydroxybenzoate. <5> the content of structural units derived from ethylene in the ethylene-α-olefin copolymer (L-2) is 30 to 70 mass% based on the total structural units constituting the copolymer (L-2); <1> ~ <4> 10. The copolymer composition for a conveyor belt according to claim 9, wherein the copolymer composition is a copolymer of a hydroxybenzoate and a hydroxybenzoate. <6> the content of the trans polyoctenylene (M) is 0.5 to 50 parts by mass relative to 100 parts by mass in total of the ethylene-α-olefin-non-conjugated polyene copolymer (L-1) and the ethylene-α-olefin copolymer (L-2); <1> ~ <5> 10. The copolymer composition for a conveyor belt according to claim 9, wherein the copolymer composition is a copolymer of a hydroxybenzoate and a hydroxybenzoate. <7> further comprising an organic peroxide, <1> ~ <6> 10. The copolymer composition for a conveyor belt according to claim 9, wherein the copolymer composition is a copolymer of a hydroxybenzoate and a hydroxybenzoate. <8> <1> ~ <7> and a layer [II] containing a fiber material, A laminate in which the layer [I] and the layer [II] are in contact with each other. <9> The layer [I] is the outermost layer. <8> The laminate according to claim 1. <10> the layer [I] is a crosslinked product of a copolymer composition for a conveyor belt; <8> or <9> The laminate according to claim 1. <11> The fibrous material of the layer [II] contains RFL-treated fibers. <8> ~ <10> 10. The laminate according to claim 9, wherein the first and second laminates are oriented in a direction perpendicular to the plane of the <12> The fiber material of the layer [II] is canvas. <8> ~ <11> 10. The laminate according to claim 9, wherein the first and second laminates are oriented in a direction perpendicular to the plane of the <13> <8> ~ <12> An industrial belt comprising the laminate according to any one of the above. [Effects of the Invention]

[0010] According to one embodiment of the present invention, there is provided a copolymer composition for a conveyor belt that can give a laminate having excellent adhesion to a layer containing a fiber material and an excellent balance between heat aging resistance and abrasion resistance. Furthermore, according to one embodiment of the present invention, a laminate and an industrial belt are provided that have an excellent balance between heat aging resistance and abrasion resistance. DETAILED DESCRIPTION OF THE INVENTION

[0011] The present invention will be described in detail below. The following description of the components may be based on a representative embodiment of the present invention, but the present invention is not limited to such an embodiment. In this specification and claims, "parts by mass" refers to parts by mass converted into solid content excluding solvent. Furthermore, a numerical range expressed by "to" means a numerical range in which the numbers before and after "to" are the lower and upper limits. Furthermore, in this specification, when referring to the amount of each component in a composition, if there are multiple substances corresponding to each component in the composition, it means the total amount of the multiple substances present in the composition, unless otherwise specified. As used herein, a combination of two or more preferred embodiments is a more preferred embodiment. In this specification, unless otherwise specified, each component in the composition or each structural unit in the polymer may be contained alone or in combination of two or more types. The present invention will be described in detail below.

[0012] <Copolymer composition for conveyor belts> The copolymer composition for a conveyor belt according to the present invention comprises an ethylene-α-olefin-non-conjugated polyene copolymer (L-1) having structural units derived from ethylene (A), structural units derived from an α-olefin (B) having 4 to 20 carbon atoms, and structural units derived from a non-conjugated polyene (C) having, per molecule, two or more partial structures selected from the group consisting of the following general formulae (I) and (II): an ethylene-α-olefin copolymer (L-2) other than (L-1) having structural units derived from ethylene and structural units derived from an α-olefin having 3 to 20 carbon atoms; and trans-polyoctenylene (M). The copolymer composition for a conveyor belt having the above structure provides a laminate having excellent adhesion to a layer containing a fibrous material and an excellent balance between heat aging resistance and abrasion resistance. The ethylene-α-olefin copolymer (L-2) other than (L-1) has a smaller amount of double bonds than the ethylene-α-olefin-non-conjugated polyene copolymer (L-1) containing a non-conjugated polyene, and therefore exhibits better heat aging resistance. Furthermore, non-conjugated polyenes are highly reactive to peroxides. Therefore, when comparing copolymer (L-1) with copolymer (L-2), copolymer (L-2) has a slower reaction rate. The inclusion of copolymer (L-2), which has a slower reaction rate than copolymer (L-1), in the copolymer composition of the present invention prolongs the life of the cleaved peroxide radicals during crosslinking using peroxide. As a result, when a laminate is formed in which a layer containing the copolymer composition and a layer containing a fiber material are in contact with each other, the amount of radicals available for reaction with the fiber material increases, thereby increasing the amount of chemical bonds between the copolymer composition and the fiber material, thereby improving the adhesive strength between the copolymer composition of the present invention and the fiber material. Each component constituting the copolymer composition for a conveyor belt will be described in detail below.

[0013] <<Ethylene-α-olefin-non-conjugated polyene copolymer (L-1)>> The ethylene-α-olefin-non-conjugated polyene copolymer (L-1) (hereinafter sometimes simply referred to as "copolymer (L-1)") has structural units derived from ethylene (A), structural units derived from an α-olefin (B) having 4 to 20 carbon atoms, and structural units derived from a non-conjugated polyene (C) containing, in the molecule, two or more partial structures selected from the group consisting of the following general formulas (I) and (II):

[0014] [ka]

[0015] [α-Olefins (B) having 4 to 20 carbon atoms] Examples of the α-olefin (B) having 4 to 20 carbon atoms (hereinafter, sometimes simply referred to as "α-olefin (B)") include 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-heptene, 1-octene, 1-decene, 1-dodecene, 1-tetradecene, 1-hexadecene, and 1-eicosene. Among these, the α-olefin (B) preferably contains an α-olefin having 4 to 8 carbon atoms such as 1-butene, 1-hexene, or 1-octene, more preferably contains 1-butene, and further preferably the α-olefin (B) is 1-butene. Such α-olefins (B) are preferred because the raw material cost is relatively low, the resulting copolymer composition for a conveyor belt exhibits excellent mechanical properties, and a conveyor belt having rubber elasticity can be obtained. These α-olefins (B) may be used alone or in combination of two or more.

[0016] [Non-conjugated polyene (C)] Examples of the non-conjugated polyene (C) include 5-vinyl-2-norbornene (VNB), norbornadiene, 1,4-hexadiene, dicyclopentadiene, etc. Among these, from the viewpoints of high availability, good reactivity with organic peroxides during the crosslinking reaction after polymerization, and ease of improving the heat resistance of the resulting laminate, it is preferable that the non-conjugated polyene (C) contains 5-vinyl-2-norbornene (VNB), and it is more preferable that the non-conjugated polyene (C) is 5-vinyl-2-norbornene (VNB). The non-conjugated polyene (C) may be used alone or in combination of two or more.

[0017] [Non-conjugated polyene (D)] The ethylene-α-olefin-non-conjugated polyene copolymer (L-1) may further contain, in addition to the structural units derived from ethylene (A), the structural units derived from the α-olefin (B) having 4 to 20 carbon atoms, and the structural units derived from the non-conjugated polyene (C), a structural unit derived from a non-conjugated polyene (D) containing only one partial structure selected from the group consisting of the general formulae (I) and (II) in one molecule.

[0018] Examples of such non-conjugated polyenes (D) include 5-ethylidene-2-norbornene (ENB), 5-methylene-2-norbornene, 5-(2-propenyl)-2-norbornene, 5-(3-butenyl)-2-norbornene, 5-(1-methyl-2-propenyl)-2-norbornene, 5-(4-pentenyl)-2-norbornene, 5-(1-methyl-3-butenyl)-2-norbornene, 5-(5-hexenyl)-2-norbornene, 5-(1-methyl-4-pentenyl)-2-norbornene, 5-(2,3-dimethyl-3-butenyl)-2-norbornene, 5-(2-ethyl-3- butenyl)-2-norbornene, 5-(6-heptenyl)-2-norbornene, 5-(3-methyl-5-hexenyl)-2-norbornene, 5-(3,4-dimethyl-4-pentenyl)-2-norbornene, 5-(3-ethyl-4-pentenyl)-2-norbornene, 5-(7-octenyl)-2-norbornene, 5-(2-methyl-6-heptenyl)-2-norbornene, 5-(1,2-dimethyl-5-hexenyl)-2-norbornene, 5-(5-ethyl-5-hexenyl)-2-norbornene, 5-(1,2,3-trimethyl-4-pentenyl)-2-norbornene, and the like. Among these, 5-ethylidene-2-norbornene (ENB) is preferred as the non-conjugated polyene (D) because it is easily available, has high reactivity with sulfur and vulcanization accelerators during the crosslinking reaction after polymerization, is easy to control the crosslinking rate, and tends to provide good mechanical properties. The non-conjugated polyene (D) may be used alone or in combination of two or more.

[0019] When the ethylene-α-olefin-non-conjugated polyene copolymer (L-1) contains a structural unit derived from a non-conjugated polyene (D) containing only one partial structure selected from the group consisting of the general formulae (I) and (II) in one molecule, the content is not particularly limited as long as the object of the present invention is not impaired, but is usually contained in a mass fraction of about 0 to 20 mass%, preferably 0 to 8 mass%, and more preferably 0.01 to 8 mass% (however, the total mass fraction of the structural units derived from (A), (B), (C) and (D) is 100 mass%).

[0020] The ethylene-α-olefin-non-conjugated polyene copolymer (L-1) may contain, as a constituent unit derived from at least one monomer selected from the aforementioned ethylene (A), the α-olefin (B) having 4 to 20 carbon atoms, the non-conjugated polyene (C), and the non-conjugated polyene (D), a constituent unit derived from a biomass-derived monomer and / or a chemically recycled monomer.

[0021] The ethylene-α-olefin-non-conjugated polyene copolymer (L-1) may contain a structural unit derived from at least one biomass-derived monomer. The biomass-derived monomer used as the raw material for the ethylene-α-olefin-non-conjugated polyene copolymer (L-1) may be biomass-derived ethylene, biomass-derived α-olefin, or biomass-derived non-conjugated polyene. An example of a biomass-derived α-olefin is biomass-derived propylene. Examples of biomass-derived non-conjugated polyenes include biomass-derived 5-ethylidene-2-norbornene (ENB) and biomass-derived 5-vinyl-2-norbornene (VNB). The monomers used as raw materials for the ethylene-α-olefin-non-conjugated polyene copolymer (L-1) may contain only biomass-derived monomers, or may contain both biomass-derived monomers and fossil fuel-derived monomers. Biomass-derived monomers such as biomass-derived ethylene, biomass-derived α-olefins, and biomass-derived non-conjugated polyenes can be obtained by known methods. It is desirable for the ethylene-α-olefin-non-conjugated polyene copolymer (L-1) to contain structural units derived from biomass-derived monomers from the viewpoint of reducing environmental impact.

[0022] The ethylene-α-olefin-non-conjugated polyene copolymer (L-1) may contain a structural unit derived from at least one chemically recycled monomer. The chemically recycled monomer used as the raw material for the ethylene-α-olefin-non-conjugated polyene copolymer (L-1) may be ethylene derived from chemical recycling, an α-olefin derived from chemical recycling, or a non-conjugated polyene derived from chemical recycling. Furthermore, the monomer used as the raw material for the ethylene-α-olefin-non-conjugated polyene copolymer (L-1) may contain only chemically recycled monomers, or may contain both chemically recycled monomers and fossil fuel-derived monomers. Chemically recycled monomers, such as ethylene derived from chemical recycling, α-olefins derived from chemical recycling, and non-conjugated polyenes derived from chemical recycling, can be obtained by known methods. It is desirable for the ethylene-α-olefin-non-conjugated polyene copolymer (L-1) to contain structural units derived from chemically recycled monomers from the viewpoint of reducing environmental impact (mainly waste generation).

[0023] The ethylene-α-olefin-non-conjugated polyene copolymer (L-1) preferably satisfies the following requirements (1) to (3).

[0024] [Requirement (1)] In the ethylene-α-olefin-non-conjugated polyene copolymer (L-1), the ratio ([A] / [B]) of the number of moles of structural units derived from ethylene (A) [A] to the number of moles of structural units derived from an α-olefin (B) having 4 to 20 carbon atoms [B] is 40 / 60 to 90 / 10, preferably 45 / 55 to 90 / 10, more preferably 50 / 50 to 85 / 15, even more preferably 55 / 45 to 80 / 20, and particularly preferably 60 / 40 to 75 / 25. The ethylene-α-olefin-non-conjugated polyene copolymer (L-1) satisfies the requirement (1), and when the copolymer (L-1) is used as a raw material for a crosslinked molded article, the resulting crosslinked molded article exhibits excellent rubber elasticity and is excellent in mechanical strength and flexibility, which is preferable. The ratio ([A] / [B]) of the number of moles of the structural units derived from ethylene (A) to the number of moles of the structural units derived from α-olefin (B) in the copolymer (L-1) is determined by the method described in the Examples below. 13 It can be determined by C-NMR.

[0025] [Requirement (2)] In the ethylene-α-olefin-non-conjugated polyene copolymer (L-1), the content ratio of the number of moles [C] of constituent units derived from the non-conjugated polyene (C) is 0.1 to 6.0 mol %, preferably 0.1 to 3.0 mol %, more preferably 0.2 to 1.0 mol %, and even more preferably 0.3 to 0.5 mol %, relative to 100 mol % in total of the [A], the [B], and the [C]. The ethylene-α-olefin-non-conjugated polyene copolymer (L-1) is preferred because it satisfies requirement (2), and the crosslinked product obtained from the copolymer composition has sufficient hardness and excellent mechanical properties. The mass fraction of the structural units derived from the non-conjugated polyene (C) in the copolymer (L-1) is determined by the formula (I) shown in the Examples below. 13 It can be determined by C-NMR.

[0026] When the proportion of the constitutional units derived from the non-conjugated polyene (C) in the ethylene-α-olefin-non-conjugated polyene copolymer (L-1) is expressed as an iodine value, it is preferably 0.14 to 20, more preferably 0.2 to 16, and even more preferably 1.0 to 10. When the proportion of the constitutional units derived from the non-conjugated polyene (C) is within the preferred iodine value range, good rubber elasticity can be obtained. The iodine value can be determined by the measurement method described in the Examples.

[0027] [Requirement (3)] The ethylene-α-olefin-non-conjugated polyene copolymer (L-1) has a B value represented by the following formula (i) of 1.20 or more, preferably 1.30 to 1.80, and more preferably 1.35 to 1.50. When the B value of the ethylene-α-olefin-non-conjugated polyene copolymer (L-1) is 1.20 or more, the alternation of the monomer units constituting the copolymer is high and the crystallinity is low, resulting in improved processability of the resulting copolymer composition.

[0028] B value = ([EX] + 2[Y]) / (2 × [E] × ([X] + [Y])) ... Formula (i) [Here, [E], [X], and [Y] represent the molar fractions of structural units derived from ethylene [A1], α-olefin [B] having 4 to 20 carbon atoms, and non-conjugated polyene [C], respectively, and [EX] represents the ethylene [A]-α-olefin [B] having 4 to 20 carbon atoms dyad chain fraction.]

[0029] The B value is an index showing the randomness of the copolymerization monomer sequence distribution in the ethylene-α-olefin-non-conjugated polyene copolymer (L-1), and [E], [X], [Y], and [EX] in the formula (i) are 13 The C-NMR spectrum can be measured and determined based on the reports of J. C. Randal [Macromolecules, 15, 353 (1982)], J. Ray [Macromolecules, 10, 773 (1977)], et al.

[0030] Furthermore, the copolymer (L-1) may satisfy the following requirements (4) to (7) in addition to the above requirements (1) to (3). The requirements (4) and (5) are both indicators related to the content of long chain branches in the copolymer (L-1).

[0031] [Requirement (4)] The complex viscosity η of ethylene-α-olefin-non-conjugated polyene copolymer (L-1) at a frequency of ω=0.1 rad / s was measured by linear viscoelasticity measurement (190℃) using a rheometer. *( ω =0.1) (Pa·sec) and complex viscosity η at frequency ω=100rad / s * ( ω =100) (Pa·sec) and the ratio P(η * ( ω =0.1) / η * ( ω =100) ), the intrinsic viscosity [η], and the mass fraction of the structural units derived from the non-conjugated polyene (C) (mass fraction of (C): mass %) satisfy the following formula (2). P / ([η] 2.9 ) ≦ (C) mass fraction × 6 Equation (2)

[0032] The rheometer used for linear viscoelasticity measurement in requirement (4) is the Ares viscoelasticity measuring device (manufactured by Rheometric Scientific), and the complex viscosity η * (ω=0.1) (Pa·sec) is measured at 190°C and 1.0% strain while changing the frequency.

[0033] Here, the complex viscosity η at frequency ω=0.1 rad / s * ( ω =0.1) and the complex viscosity η at frequency ω=100rad / s * ( ω =100) The ratio P(η * ( ω =0.1) / η * ( ω =100) ) represents the frequency dependence of viscosity, and is the left side of equation (2), P / ([η] 2.9) tends to show a high value when there is a lot of long-chain branching, although it is affected by factors such as short-chain branching and molecular weight. Generally, in an ethylene-α-olefin-non-conjugated polyene copolymer, the more structural units derived from non-conjugated polyenes it contains, the more long-chain branching it tends to have. However, the ethylene-α-olefin-non-conjugated polyene copolymer (L-1) has less long-chain branching than the conventionally known ethylene-α-olefin-non-conjugated polyene copolymers, and is therefore thought to satisfy the above formula (2). The above ratio P was determined by measuring the complex viscosity of the copolymer (L-1) at 190°C, strain 1.0% and changing the frequency using a viscoelasticity measuring device Ares (manufactured by Rheometric Scientific), and then calculating the complex viscosity η at a frequency ω = 0.1 rad / s. * ( ω =0.1) and the complex viscosity η at frequency ω=100rad / s * ( ω =100) The intrinsic viscosity [η] is the value measured in decalin at 135°C.

[0034] The ethylene-α-olefin-non-conjugated polyene copolymer (L-1) preferably satisfies the following formula (2′): P / ([η] 2.9 ) ≦ (C) mass fraction × 5.7 Equation (2') The intrinsic viscosity [η] means the value measured in decalin at 135°C.

[0035] [Requirement (5)] The ethylene-α-olefin-non-conjugated polyene copolymer (L-1) was analyzed by 3D-GPC to determine the number of long chain branches (LCB) per 1000 carbon atoms. 1000C ) and the natural logarithm of the weight average molecular weight (Mw) [Ln(Mw)] satisfy the following formula (3). LCB 1000C ≦1-0.07×Ln(Mw) Equation (3)

[0036] The above formula (3) specifies the upper limit of the long chain branch content per unit carbon number of the ethylene-α-olefin-non-conjugated polyene copolymer (L-1). Such an ethylene-α-olefin-non-conjugated polyene copolymer (L-1) is preferred because it contains a small proportion of long chain branches, has excellent curing properties when crosslinked using a peroxide, and produces molded articles with excellent heat aging resistance.

[0037] The ethylene-α-olefin-non-conjugated polyene copolymer (L-1) preferably satisfies the following formula (3′): LCB 1000C ≦1-0.071×Ln(Mw)...Equation (3') Here, the weight average molecular weight (Mw) and the number of long chain branches (LCB) per 1000 carbon atoms 1000C ) can be determined by a structural analysis method using 3D-GPC. In this specification, it is specifically determined as follows.

[0038] Using a 3D-high temperature GPC device (PL-GPC220, Polymer Laboratories), the absolute molecular weight distribution of ethylene-α-olefin-non-conjugated polyene copolymer (L-1) is determined, and at the same time, the intrinsic viscosity is determined using a viscometer. The main measurement conditions are as follows: Detector: Differential refractometer / GPC device built-in 2-angle light scattering photometer PD2040 type (manufactured by Precison Detectors) Bridge-type viscometer PL-BV400 (Polymer Laboratories) Column: TSKgel GMH HR -H(S)HT x 2 + TSKgel GMH HR -M(S)×1 piece (Each piece has an inner diameter of 7.8mm and a length of 300mm) Temperature: 140℃ Mobile phase: 1,2,4-trichlorobenzene (containing 0.025% BHT) Injection volume: 0.5mL Sample concentration: ca 1.5mg / mL Sample filtration: Filtration through a sintered filter with a pore size of 1.0 μm The dn / dc value required to determine the absolute molecular weight is determined for each sample from the dn / dc value (differential value of refractive index n with respect to concentration c) of 0.053 for standard polystyrene (molecular weight 190,000) and the response intensity of the differential refractometer per unit injected mass.

[0039] The long chain branching parameter g'i for each eluted component was calculated from the relationship between the intrinsic viscosity measured in decalin at 135 obtained by a viscometer and the absolute molecular weight obtained by a light scattering photometer using equation (v-1).

[0040]

number

[0041] where [η]=KM v The relational equation, v = 0.725, was applied. This equation is called the Mark-Houwink-Sakurada equation, where K is the solvent constant, M is the absolute molecular weight, and v is the conformation of the polymer chain (i.e., the molecular shape, degree of bending, and other molecular extensions) in the measurement solvent at the measurement temperature. Furthermore, the average values ​​of g' were calculated from the following formulas (v-2), (v-3), and (v-4): A trendline assuming only short chain branches was determined for each sample.

[0042]

number

[0043] Furthermore, the weight average long chain branching parameter g' represented by the above formula (v-3) w The number of branch points per molecular chain: BrNo, and the number of long chain branches per 1000 carbon atoms: LCB 1000C The branching degree λ per unit molecular weight was calculated. BrNo was calculated using the Zimm-Stockmayer formula (v-5). 1000C The calculation of and λ was performed using the following equations (v-6) and (v-7). g is the long chain branching parameter calculated from the radius of gyration Rg, and the following simple correlation is established between g' calculated from the intrinsic viscosity: g=g' (1 / ε) Various values ​​have been proposed for ε in the above formula depending on the shape of the molecule. Here, the calculation was performed assuming ε = 1 (i.e., g' = g).

[0044]

number

[0045] ·≠arNo / M···(V-6) LCB 1000C =λ×14000 (V-7) In formula (V-7), 14,000 represents the molecular weight of 1,000 methylene (CH2) units.

[0046] The ethylene-α-olefin-non-conjugated polyene copolymer (L-1) has an intrinsic viscosity [η] measured in decalin at 135°C of preferably 0.1 to 5 dL / g, more preferably 0.5 to 5.0 dL / g, even more preferably 1.0 to 3.0 dL / g, and particularly preferably 1.5 to 2.0 dL / g.

[0047] The weight average molecular weight (Mw) of the ethylene-α-olefin-non-conjugated polyene copolymer (L-1) is preferably 10,000 to 600,000, more preferably 50,000 to 500,000, still more preferably 100,000 to 400,000, and particularly preferably 150,000 to 300,000.

[0048] The ethylene-α-olefin-non-conjugated polyene copolymer (L-1) preferably satisfies both the above-mentioned intrinsic viscosity [μm] and weight average molecular weight (Mw). In the ethylene-α-olefin-non-conjugated polyene copolymer (L-1), the non-conjugated polyene (C) preferably contains 5-vinyl-2-norbornene (VNB), and more preferably is 5-vinyl-2-norbornene (VNB). That is, in the above-mentioned formula (1), formula (2), and formula (4) described later, the "mass fraction of (C)" is preferably the "mass fraction of VNB" (mass %).

[0049] As described above, the ethylene-α-olefin-non-conjugated polyene copolymer (L-1) preferably contains, in addition to the structural units derived from the above (A), (B), and (C), structural units derived from a non-conjugated polyene (D) containing only one partial structure selected from the group consisting of the general formulae (I) and (II) in the molecule, in a mass fraction of 0 to 20% by mass (where the total mass fractions of (A), (B), (C), and (D) is 100% by mass).

[0050] [Requirement (6)] The complex viscosity η of ethylene-α-olefin-non-conjugated polyene copolymer (L-1) at a frequency of ω=0.01 rad / s was measured by linear viscoelasticity measurement (190℃) using a rheometer. * ( ω =0.01) (Pa·sec) and the complex viscosity η at frequency ω=10 rad / s * ( ω =10) It is preferable that the apparent iodine value (Pa·sec) and the apparent iodine value derived from the non-conjugated polyene (C) satisfy the following formula (4): Log{η * ( ω =0.01)} / Log{η * ( ω =10)}≦0.0753 × {apparent iodine value derived from non-conjugated polyene (C)} + 1.42 Equation (4) Here, the complex viscosity η * ( ω =0.01) and complex viscosity η * ( ω=10) is the complex viscosity η of requirement (4), except that in the measurement method using the viscoelasticity measuring device of requirement (4), the measurement frequency is changed to frequency ω = 0.01 rad / s and frequency ω = 10 rad / s. * ( ω =0.1) and complex viscosity η * ( ω =100) It can be determined in the same manner as in the measurement method of

[0051] The apparent iodine value derived from the non-conjugated polyene (C) can be calculated by the following formula: Apparent iodine value derived from (C) = mass fraction of (C) × 253.81 / molecular weight of (C) In the above formula (4), the left side represents the shear rate dependency, which is an index of the amount of long chain branches, and the right side represents an index of the content of non-conjugated polyene (C) that is not consumed as long chain branches during polymerization. When requirement (vii) and the above formula (4) are satisfied, the degree of long chain branching is not too high, which is preferable. On the other hand, when the above formula (4) is not satisfied, it is clear that a large proportion of the copolymerized non-conjugated polyene (C) is consumed in the formation of long chain branches.

[0052] [Requirement (7)] <<Glass transition temperature>> The ethylene-α-olefin-non-conjugated polyene copolymer (L-1) preferably has a glass transition temperature (Tg) of -100 to -65°C, and more preferably -80 to -70°C. The glass transition temperature (Tg) is measured in accordance with JIS K7121 (2012) using a differential scanning calorimeter (PerkinElmer, model number: DSC8500) at a heating rate of 10 / min, and is determined by differential scanning calorimetry (DSC) measurement of the intersection of the tangent point at the baseline and the inflection point where enthalpy relaxation is observed, or the midpoint of the displacement.

[0053] <Production of Ethylene-α-Olefin-Non-Conjugated Polyene Copolymer (L-1)> The method for producing the ethylene-α-olefin-non-conjugated polyene copolymer (L-1) is not particularly limited, and any known production method can be used. However, it is preferably a copolymer obtained by copolymerizing monomers in the presence of a metallocene compound, and more preferably a copolymer obtained by copolymerizing monomers in the presence of a catalyst system containing a metallocene compound. Specific examples of the production method for the ethylene-α-olefin-non-conjugated polyene copolymer (L-1) include the production methods using metallocene catalysts described in JP 2018-119096 A and WO 2015 / 122495 A.

[0054] <<Ethylene-α-olefin copolymer (L-2)>> The ethylene-α-olefin copolymer (L-2) other than the above (L-1) (hereinafter, may be simply referred to as "ethylene-α-olefin copolymer (L-2)") contains structural units derived from ethylene and structural units derived from an α-olefin having 3 to 20 carbon atoms.

[0055] The α-olefin preferably has 3 to 12 carbon atoms, more preferably 4 to 8 carbon atoms, in order to obtain a conveyor belt having excellent mechanical strength. Specific examples of such α-olefins include propylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-heptene, 1-octene, 1-nonene, 1-decene, 1-undecene, 1-dodecene, 1-tridecene, 1-tetradecene, 1-pentadecene, 1-hexadecene, 1-heptadecene, 1-octadecene, 1-nonadecene, 1-eicosene, 9-methyl-1-decene, 11-methyl-1-dodecene, 12-ethyl-1-tetradecene, etc. Among these, propylene, 1-butene, 1-hexene, and 1-octene are preferred as α-olefins having 3 to 20 carbon atoms, and propylene is more preferred. These α-olefins may be used alone or in combination of two or more.

[0056] In the ethylene-α-olefin copolymer (L-2), the content of structural units derived from ethylene is preferably 30 to 85 mass%, more preferably 30 to 70 mass%, even more preferably 40 to 60 mass%, and particularly preferably 45 to 55 mass%, based on all structural units constituting the copolymer (L-2). When the content of the structural units derived from ethylene is within the above range, a copolymer composition for a conveyor belt having excellent compatibility with the copolymer (L-1) can be obtained.

[0057] The copolymer composition for a conveyor belt preferably contains the polymer (L-1) in an amount of 90 to 10 parts by mass, preferably 80 to 20 parts by mass, more preferably 70 to 30 parts by mass, and particularly preferably 60 to 40 parts by mass, and the copolymer (L-2) in an amount of 10 to 90 parts by mass, preferably 20 to 80 parts by mass, more preferably 30 to 70 parts by mass, and particularly preferably 40 to 60 parts by mass, relative to 100 parts by mass of the total amount of the copolymer (L-1) and the copolymer (L-2).

[0058] <<Trans-polyoctenylene (M)>> Trans polyoctenylene (M) is a polymer of octenylene having a trans structure, and is mainly a metathesis polymer of cyclooctene having a trans double bond. Note that the metathesis polymer means a polymer obtained by metathesis polymerization of trans double-bonded cyclooctene using a metal atom as a polymerization catalyst. By containing trans-polyoctenylene (M), the copolymer composition has good adhesion to other materials, for example, layers containing fibrous materials such as industrial belts, and the crosslinked laminate has excellent adhesive strength to layers containing fibrous materials.

[0059] The trans-polyoctenylene (M) may be synthesized or may be a commercially available product, such as VESTENAMER (trade name) from Evonik Industries.

[0060] The content of trans-polyoctenylene (M) is preferably 0.5 to 50 parts by mass, more preferably 1 to 30 parts by mass, even more preferably 2 to 15 parts by mass, and particularly preferably 3 to 10 parts by mass, relative to 100 parts by mass in total of the ethylene-α-olefin-non-conjugated polyene copolymer (L-1) and the copolymer (L-2).

[0061] [Organic peroxide] The copolymer composition preferably further contains an organic peroxide. Organic peroxides are a type of crosslinking agent, and specific examples thereof include dicumyl peroxide (DCP), di-tert-butyl peroxide, 2,5-di-(tert-butylperoxy)hexane, 2,5-dimethyl-2,5-di-(tert-butylperoxy)hexane, 2,5-dimethyl-2,5-di-(tert-butylperoxy)hexyne-3, 1,3-bis(tert-butylperoxyisopropyl)benzene, 1,1-bis(tert-butylperoxy)-3,3,5-trimethylcyclohexane, n-butyl-4,4-bis(tert-butylperoxy)valerate, benzoyl peroxide, p-chlorobenzoyl peroxide, 2,4-dichlorobenzoyl peroxide, tert-butyl peroxybenzoate, ert-butylperoxyisopropyl carbonate, diacetyl peroxide, lauroyl peroxide, and tert-butylcumyl peroxide. Among these, the organic peroxide is preferably dicumyl peroxide (DCP), 2,5-di-(tert-butylperoxy)hexane, 2,5-dimethyl-2,5-di-(tert-butylperoxy)hexane, 2,5-dimethyl-2,5-di-(tert-butylperoxy)hexyne-3, 1,3-bis(tert-butylperoxyisopropyl)benzene, 1,1-bis(tert-butylperoxy)-3,3,5-trimethylcyclohexane, or n-butyl-4,4-bis(tert-butylperoxy)valerate.

[0062] The content of the organic peroxide is preferably 0.1 to 30 parts by mass, more preferably 0.5 to 20 parts by mass, even more preferably 1.0 to 10 parts by mass, and particularly preferably 1.5 to 5.0 parts by mass, per 100 parts by mass of the total amount of the copolymer (L-1) and the copolymer (L-2). The organic peroxides may be contained in the composition either alone or in combination of two or more.

[0063] The copolymer composition for a conveyor belt may contain components other than the above-mentioned copolymer (L-1), copolymer (L-2), trans-polyoctenylene (M) and organic peroxide (hereinafter also referred to as "other components"), within the range that does not impair the effects of the present invention.

[0064] Examples of other components include crosslinking aids, softeners, antioxidants, processing aids, activators, heat stabilizers, weather stabilizers, antistatic agents, colorants, lubricants, thickeners, antifoaming agents, foaming agents, and foaming aids. These other components may be used alone or in combination of two or more.

[0065] [Carbon black] Carbon black is one of the known rubber reinforcing agents compounded in rubber compositions, and is an inorganic substance generally called carbon black. Specific examples of carbon black include Asahi #55G, Asahi #60G, Asahi #60UG, and Asahi #70 (all manufactured by Asahi Carbon Co., Ltd.), Seast (V, SO, 116, 3, 6, 9, SP, TA, etc.) carbon black (manufactured by Tokai Carbon Co., Ltd.), and carbon blacks that have been surface-treated with a silane coupling agent or the like. The carbon black content is preferably 5 to 120 parts by mass, more preferably 10 to 100 parts by mass, even more preferably 20 to 70 parts by mass, and particularly preferably 30 to 50 parts by mass, per 100 parts by mass of the total amount of copolymer (L-1) and the copolymer (L-2). The carbon black may be contained in the composition either alone or in combination of two or more.

[0066] 〔silica〕 The copolymer composition for conveyor belts preferably contains silica. Silica has hydroxyl groups, which is thought to improve the adhesiveness of the composition itself and the adhesiveness and adhesion to fibrous materials. Silica usually has a specific surface area of ​​5 to 200 m 2 / g, preferably 5 to 190 m 2 / g, more preferably 5 to 180m 2 / g range. A suitable example of silica is ULTRASIL VN2 (Evonik Industries).

[0067] The content of silica is preferably 1 to 100 parts by mass, more preferably 3 to 50 parts by mass, even more preferably 5 to 30 parts by mass, and particularly preferably 7 to 20 parts by mass, per 100 parts by mass of the total of copolymer (L-1) and copolymer (L-2). The silica may be contained in the composition either alone or in combination of two or more types.

[0068] [Anti-aging agent] As the antioxidant, a conventionally known antioxidant can be used, and examples thereof include amine-based antioxidants, phenol-based antioxidants, and sulfur-based antioxidants. Examples of the antioxidant include aromatic secondary amine antioxidants such as phenylbutylamine and N,N-di-2-naphthyl-p-phenylenediamine; phenolic antioxidants such as dibutylhydroxytoluene and tetrakis[methylene(3,5-di-t-butyl-4-hydroxy)hydrocinnamate]methane (trade name: Irganox 1010, manufactured by BASF); thioether antioxidants such as bis[2-methyl-4-(3-n-alkylthiopropionyloxy)-5-t-butylphenyl]sulfide; dithiocarbamate antioxidants such as nickel dibutyldithiocarbamate; and 2-mercaptobenzoylimidazole (trade name: Examples of suitable antioxidants include sulfur-based antioxidants such as Sandant MB (manufactured by Sanshin Chemical Industry Co., Ltd.), 2-mercaptobenzimidazole, zinc salt of 2-mercaptobenzimidazole, dilauryl thiodipropionate, and distearyl thiodipropionate. The content of the antioxidant is preferably 0.1 to 20 parts by mass, more preferably 1.0 to 15 parts by mass, even more preferably 3.0 to 10 parts by mass, and particularly preferably 5.0 to 7.0 parts by mass, per 100 parts by mass of the total amount of the copolymer (L-1) and the copolymer (L-2). These antioxidants may be used alone or in combination of two or more.

[0069] [Crosslinking aid] Examples of the crosslinking aid include sulfur; quinone dioxime-based crosslinking aids such as p-quinone dioxime; acrylic crosslinking aids such as ethylene glycol dimethacrylate and trimethylolpropane trimethacrylate; allyl crosslinking aids such as diallyl phthalate and triallyl isocyanurate; maleimide-based crosslinking aids; divinylbenzene; and metal oxides such as zinc oxide (e.g., ZnO#1 / zinc oxide type 2 (JIS standard (K-1410)), manufactured by Hakusui Tech Co., Ltd.), magnesium oxide, and activated zinc oxide (e.g., zinc oxide such as "META-Z102" (trade name; manufactured by Inoue Lime Industry Co., Ltd.)). When a crosslinking aid is contained, the content of the crosslinking aid in the copolymer composition for a conveyor belt is usually 0.5 to 10 mol, preferably 0.5 to 7 mol, more preferably 1 to 6 mol, per 1 mol of the organic peroxide. The crosslinking aid may be contained in the composition either alone or in combination of two or more.

[0070] [Softener] Examples of softeners include petroleum-based softeners such as process oil, lubricating oil, paraffin oil, liquid paraffin, petroleum asphalt, and Vaseline; coal tar-based softeners such as coal tar; fatty oil-based softeners such as castor oil, linseed oil, rapeseed oil, soybean oil, and palm oil; waxes such as beeswax and carnauba wax; naphthenic acid, pine oil, rosin, or derivatives thereof; synthetic polymeric substances such as terpene resins, petroleum resins, and coumarone-indene resins; ester-based softeners such as dioctyl phthalate and dioctyl adipate; and others such as microcrystalline wax, liquid polybutadiene, modified liquid polybutadiene, hydrocarbon-based synthetic lubricating oils, tall oil, and sub(factice). Among these, petroleum-based softeners are preferred, and process oil is particularly preferred. When the copolymer composition for a conveyor belt contains a softener, the content of the softener is generally 2 to 100 parts by mass, preferably 5 to 50 parts by mass, more preferably 6 to 30 parts by mass, even more preferably 7 to 20 parts by mass, and particularly preferably 8 to 15 parts by mass, per 100 parts by mass of the total of the copolymer (L-1) and the copolymer (L-2). The softening agent may be contained in the composition either alone or in combination of two or more.

[0071] [Processing aids] Examples of processing aids include known compounds generally compounded in rubber compositions as processing aids. Specific examples include ricinoleic acid, stearic acid, palmitic acid, lauric acid, barium stearate, zinc stearate, calcium stearate, zinc laurate, and esters thereof. Among these, stearic acid is preferred as the processing aid.

[0072] When the copolymer composition for a conveyor belt contains a processing aid, the amount of the processing aid is usually 0.1 to 3 parts by mass, preferably 0.5 to 2.0 parts by mass, per 100 parts by mass of the total of the copolymer (L-1) and the copolymer (L-2). When the content of the processing aid is within the above range, the copolymer composition for a conveyor belt has excellent processability, such as kneading processability, extrusion processability, and injection moldability. The processing aid may be used alone or in combination of two or more kinds.

[0073] The Mooney viscosity (ML) of the copolymer composition for a conveyor belt when it does not contain the organic peroxide (1+4) 100) is preferably 20 to 150, more preferably 30 to 100, even more preferably 40 to 70, and particularly preferably 50 to 60. Mooney viscosity (ML (1+4) 100) in the above range, excellent kneading processability is obtained. Mooney viscosity (ML (1+4) 100) can be determined by the method described in the Examples below.

[0074] <Method of producing copolymer composition for conveyor belt> In a method for producing the copolymer composition for conveyor belts, for example, the copolymer (L-1), the copolymer (L-2), the trans-polyoctenylene (M), and, if necessary, a softener, processing aid, crosslinking aid, etc. are kneaded for 2 to 20 minutes using an internal mixer (internal mixer) such as a Banbury mixer, kneader, or intermix. Next, additives such as a crosslinking agent, softener, crosslinking aid, and vulcanization accelerator are added to the resulting blend using rolls such as open rolls or a kneader, and the vulcanization accelerator and crosslinking aid are added as necessary. The mixture is kneaded for 5 to 30 minutes at a roll temperature of 40 to 80°C, and then separated out to prepare the composition.

[0075] When the kneading temperature in an internal mixer is low, the organic peroxide may be kneaded together with the copolymer (L-1), the copolymer (L-2) and the trans polyoctenylene (M).

[0076] [Laminate] The laminate according to the present invention preferably comprises a layer [I] containing the copolymer composition and a layer [II] containing a fibrous material, and the layers [I] and [II] are in contact with each other, and the layer [I] is preferably the outermost layer.

[0077] <<Layer [I]>> The layer [I] preferably contains the above copolymer composition, and more preferably is a crosslinked product of the above copolymer composition for a conveyor belt.

[0078] <<Layer[II]>> The layer [II] contains a fibrous material. At least a part of the layer [II] may contain a fibrous material.

[0079] <<Fiber materials>> The fiber material is not particularly limited, and various known fiber materials can be used, including natural fibers such as cotton and wood cellulose fiber, organic fiber materials such as fibers made of synthetic resins such as polyamide, polyester, polyvinyl alcohol, rayon, polyparaphenylene benzobisoxazole, polyethylene, polypropylene, polyarylate, polyimide, polyphenylene sulfide, polyether ether ketone, polylactic acid, polycaprolactone, polybutylene succinate, and fluorine-based polymers, and inorganic fiber materials such as glass fiber, PAN-based carbon fiber, pitch-based carbon fiber, alumina fiber, silicon carbide fiber, aluminum borate fiber, and potassium titanate whisker.

[0080] These fiber materials may be long fibers (filaments) or short fibers (staples).Furthermore, the fiber materials may be cord yarns, spun yarns, woven fabrics, knitted fabrics, canvas, nonwoven fabrics, etc. Among these, canvas is preferred as the fiber material.

[0081] Examples of the polyamide include aliphatic polyamides such as nylon 6, nylon 6,6, and nylon 6,10; semi-aromatic polyamides such as polymetaxylene adipamide (MXD6), polyhexamethylene terephthalamide (6T), or copolyamides containing these units; and wholly aromatic polyamides such as polybenzamide, polyp-phenylene terephthalamide, and polyp-m-phenylene isophthalamide.

[0082] <<RFL treatment>> In addition, these fiber materials may be surface-treated by known methods in order to improve the adhesiveness between the fiber materials or between the above layer [I]. Examples of the surface treatment method for the fiber materials include methods such as resorcinol-formalin-latex (RFL) treatment.

[0083] RFL treatment is an adhesion treatment of fiber materials using a treatment liquid (RFL liquid) containing resorcinol-formalin-latex. The RFL liquid is a mixed liquid of an initial condensate of resorcinol and formalin and a rubber latex. Examples of the rubber latex include styrene-butadiene-vinylpyridine terpolymer (VP), styrene-butadiene copolymer (SBR), chloroprene (CR), acrylonitrile-butadiene copolymer (NBR), hydrogenated NBR (H-NBR), chlorosulfonated ethylene (CSM), and natural rubber. The rubber latex may be used alone or in a blend of two or more. It is preferable that the fiber material of layer [II] includes fibers treated with resorcinol-formalin-latex (RFL).

[0084] <Method for manufacturing the laminate> The method for manufacturing the laminate is not particularly limited, and known methods for manufacturing laminates can be adopted. Examples of methods for producing a laminate include a method of laminating a layer [I] containing an uncrosslinked copolymer composition, which has been produced (molded) in advance by a known method, with a layer [II] containing a fiber material, and then crosslinking the layer [I] containing the resin composition; a method of laminating a layer [I] containing a crosslinked resin composition with a layer [II] containing a fiber material; or a method of extrusion coating a layer [I] containing a resin composition onto a layer [II] containing a fiber material, and then crosslinking the layer [I] containing the resin composition.

[0085] The method for preparing the resin composition is not particularly limited, and examples thereof include a method in which the ethylene-α-olefin-non-conjugated polyene copolymer (L-1), copolymer (L-2), trans-polyoctenylene (M), and, as necessary, optional components such as the organic peroxide, crosslinking aid, silica, softener, antioxidant, and processing aid are kneaded using various known kneading and mixing devices, for example, a Banbury mixer, a kneader, an internal mixer (internal mixer) such as an Intermix, and a roll.

[0086] In addition, the uncrosslinked resin composition obtained by kneading may be molded into a desired shape by various molding methods such as an extrusion molding machine, a calendar roll, a press, an injection molding machine, or a transfer molding machine, and then the resin composition may be crosslinked to form a layer [I] and laminated (bonded) with a layer [II], or the uncrosslinked resin composition may be molded into a desired shape by the above-mentioned method and then laminated (bonded) with a layer [II] and crosslinked.

[0087] The method for crosslinking the layer [I] is not particularly limited, and examples thereof include a method of heating using a crosslinking agent, or a method of irradiating with light, sputum, or electron beams.

[0088] Furthermore, crosslinking may be performed using a mold or without a mold. When crosslinking is performed without a mold, the molding and crosslinking steps are usually performed continuously. Heating methods in the crosslinking tank include heating tanks using hot air, glass bead fluidized beds, UHF (ultra-high frequency electromagnetic waves), steam, etc.

[0089] <<Applications of laminates>> The laminate is suitably used for, for example, automobile hoses, water hoses, gas hoses; industrial belts such as transmission belts and conveyor belts; and escalator handrails. An industrial belt comprising the laminate has an excellent balance of heat aging resistance and abrasion resistance.

[0090] Examples of the automotive hose include brake hoses, radiator hoses, heater hoses, and air cleaner hoses. Examples of the power transmission belt include a V-belt, a flat belt, a toothed belt, etc. Examples of the conveyor belt include a light conveyor belt, a cylindrical belt, a rough-top belt, a flanged conveyor belt, a U-shaped guide conveyor belt, a V-guide conveyor belt, etc. [Example]

[0091] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples. In the following description, "parts" means "parts by mass" unless otherwise specified. The present invention will be explained in more detail below based on examples, but the present invention is not limited to these examples in any way. In the examples and comparative examples, the following copolymers were used.

[0092] [Ethylene-α-olefin-non-conjugated polyene copolymer (L-1)] As the ethylene-α-olefin-non-conjugated polyene copolymer (L-1), the ethylene-1-butene-5-vinyl-2-norbornene (VNB) copolymer obtained in Production Example 1 (hereinafter sometimes referred to as ethylene-based copolymer (L-1)) was used.

[0093] [Production Example 1] Using a 300 L volume polymerization vessel equipped with a stirring blade, a continuous polymerization reaction of ethylene, 1-butene, and 5-vinyl-2-norbornene (VNB) was carried out at 95°C. Hexane (feed rate: 30.5 L / h) was used as the polymerization solvent and continuously supplied to the polymerization reactor so that the ethylene feed rate was 5.3 kg / h, the 1-butene feed rate was 21.5 kg / h, the 5-vinyl-2-norbornene (VNB) feed rate was 566 g / h, and the hydrogen feed rate was 10 NL / h. The polymerization pressure was maintained at 1.6 MPaG and the polymerization temperature at 95°C. Di(p-tolyl)methylene(cyclopentadienyl)(octamethyloctahydrodibenzofluorenyl)zirconium dichloride was continuously fed to the polymerization reactor at a feed rate of 0.00903 mmol / h. Additionally, (C6H5)3CB(C6F5)4 was continuously fed to the polymerization reactor at a feed rate of 0.045 mmol / h as a cocatalyst, and triisobutylaluminum (TIBA) was continuously fed to the polymerization reactor at a feed rate of 30 mmol / h as an organoaluminum compound. In this way, a polymerization reaction mixture containing 20 mass% of ethylene-1-butene-5-vinyl-2-norbornene (VNB) copolymer was obtained. A small amount of methanol was added to the polymerization reaction mixture withdrawn from the bottom of the polymerization reactor to terminate the polymerization reaction. The ethylene-1-butene-5-vinyl-2-norbornene (VNB) copolymer was separated from the solvent by steam stripping and then dried overnight at 80°C under reduced pressure. By the above procedure, ethylene-1-butene-5-vinyl-2-norbornene (VNB) copolymer (ethylene copolymer (L-1)) was obtained at a rate of 8.5 kg / h. The physical properties of the obtained ethylene copolymer (L-1) are shown below.

[0094] <<Physical properties of ethylene copolymer (L-1)>> Structural units derived from ethylene: 66.3 mol% Structural units derived from 1-butene: 33.4 mol% Structural units derived from 5-vinyl-2-norbornene (VNB): 0.4 mol% Mooney viscosity (ML (1+4) 100℃):31 B value: 1.4 Ratio P(η * (ω=0.1) / η * (ω=100) ): 15.7 Mass fraction of Mw×[C] / 100 / Molecular weight of [C]: 21.0 P / ([η]^2.9): 3.3 Mass fraction of [C]×6: 6.6 Log{η * (ω=0.01)} / Log{η * (ω=10)}: 1.26 0.0753×{Apparent iodine value derived from [C]} + 1.42: 1.60 Note that the above "mass fraction of [C]" means the mass fraction of the structural unit derived from 5-vinyl-2-norbornene (VNB). Number of branch points per molecular chain (BrNo): 0.94 Limiting viscosity [η]: 1.71 dl / g Weight average molecular weight (Mw): 229040 Glass transition temperature (Tg): -71.7 °C LCB 1000C : 0.02 pieces / 1000C 1 - 0.07×Ln(Mw): 0.14

[0095] The molar amount (mol%) was 1 determined by intensity measurement using an H-NMR spectrometer. Details of the measurement conditions are described in International Publication No. 2015 / 122415.

[0096] <> The B value of the ethylene-based copolymer (L-1) was measured with o-dichlorobenzene-d4 / benzene-d6 (4 / 1 [v / v]) as the measurement solvent at a measurement temperature of 120 °C 13 and a C-NMR spectrum (100 MHz, ECX400P manufactured by JEOL Ltd.) was measured and calculated based on the following formula (i). B value = ([EX] + 2[Y]) / [2×[E]×([X] + [Y])] ··· (i) [Here, [E], [X], and [Y] represent the molar fractions of structural units derived from ethylene [A], α-olefin [B] having 4 to 20 carbon atoms, and non-conjugated polyene [C], respectively, and [EX] represents the ethylene [A]-α-olefin [B] having 4 to 20 carbon atoms dyad chain fraction.]

[0097] <<ratio P>> The rheometer used was a viscoelasticity measuring device, Ares (manufactured by Rheometric Scientific), and the complex viscosity η of the ethylene copolymer (L-1) was measured at a frequency of ω = 0.1 rad / s under the conditions of 190 °C and 1.0% strain. * (ω=0.1) , and the complex viscosity η at frequency ω=100 rad / s * (ω=100) (All units are Pa·sec) were measured. * (ω=0.1) and η * (ω=100) The ratio of complex viscosity P(η * (ω=0.1) / η * (ω=100) ) was calculated.

[0098] [Ethylene-α-olefin copolymer (L-2)] The ethylene-α-olefin copolymer used was the following ethylene-propylene copolymer (L-2) (hereinafter sometimes referred to as "ethylene copolymer (L-2)"). Ethylene-propylene copolymer Product name: Mitsui EPT 0045: Mooney Viscosity ML (1+4) 100 = 40, ethylene content = 51% by mass.

[0099] [Trans-polyoctenylene (M)] As the trans-polyoctenylene (M), VESTENAMER 8012, a trade name of Evonik Industries, was used.

[0100] <<Mooney viscosity>> The Mooney viscosity (ML (1+4) 100) was measured using a Mooney viscometer (Shimadzu Corporation, Model SMV202) in accordance with JIS K6300 (1994).

[0101] <<Crosslinkability>> The crosslinking rate (tc90) of the copolymer composition (compound-1) was measured as follows using a curing measuring device: MDR2000 (manufactured by ALPHATECHNOLOGIES) under the measurement conditions of a temperature of 170°C and a time of 30 minutes. The change in torque obtained under conditions of constant temperature and constant shear rate was measured. The difference between the maximum torque (S'Max) and the minimum torque (S'Min): S'max - S'min [dNm]; the time when the torque of the measured sample increased by 1 [dNm] after reaching the minimum torque S'min: TS1 [min]; the time [min] when the torque of the measured sample reached 90% of the minimum torque S'min, with the maximum torque S'max being 100%, tc90; and MCR [dNm / min] were calculated. The smaller the tc90, the faster the crosslinking rate and the better the crosslinking properties.

[0102] <<Adhesiveness>> The peak value (gf) (maximum value) measured using a probe tack tester under the following conditions (23°C) was evaluated as an index of the tackiness of the uncrosslinked sheet produced as described below. Test piece: 1mm thick uncrosslinked sheet 5mm diameter stainless steel probe Approach speed: 120mm / min. Pressure: 100g Pressurization time: 200 seconds. Peeling speed: mm / min. Temperature at which the probe and test piece (uncrosslinked sheet) are placed: 23°C

[0103] <<Physical properties of cross-linked sheets>> ·Hardness (Duro-A) The hardness (type A durometer, Duro-A) of the crosslinked sheet produced under the conditions (170°C x 15 min) described below was measured in accordance with JIS K 6253. First, six 2mm-thick crosslinked sheets with smooth surfaces were used, and the flat parts were stacked to a thickness of approximately 12mm. However, test pieces containing foreign matter, bubbles, or scratches were not used. The dimensions of the test piece's measurement surface were set so that measurements could be made with the tip of the indenter at least 12mm away from the edge of the test piece.

[0104] Tensile stress (modulus), tensile stress at break and tensile elongation at break The modulus, tensile stress at break and tensile elongation at break of the crosslinked sheet prepared under the conditions described below (170°C x 15 min) were measured by the following methods. A 2 mm thick crosslinked sheet was punched out to prepare a No. 3 dumbbell test piece as specified in JIS K 6251 (1993). Using this test piece, a tensile test was carried out according to the method specified in JIS K 6251 (1993), Section 3, at a measurement temperature of 25°C and a tensile speed of 500 mm / min. The tensile stress (25% modulus (M25), 50% modulus (M50), 100% modulus (M100), 200% modulus (M200), 300% modulus (M300)), tensile stress at break (TB), and tensile elongation at break (EB) were measured when the elongation of the crosslinked sheet was 25% to 300%.

[0105] <<Heat aging resistance>> A crosslinked sheet prepared under the conditions described below (170°C x 15 min) was subjected to a heat aging test (180°C x 72 hours) in which the sheet was held at 180°C for 72 hours (hrs) according to JIS K 6257. After the heat aging test, the hardness (Duro-A), tensile stress at break (MPa), and tensile elongation at break (%) of the sheet were measured using the methods described above in the sections [Hardness (Duro-A)] and [Modulus, tensile stress at break, and tensile elongation at break]. The AH (the difference in hardness before and after the heat aging test) was determined by subtracting the hardness (Duro - A) of the cross - linked sheet before the heat aging test from the value of the hardness (Duro - A) of the cross - linked sheet after the heat resistance aging test (180°C × 72 hours). Furthermore, the change rate (%) [Ac(TB)] of the tensile break point stress (TB) and the change rate (%) [Ac(EB)] of the tensile break point elongation (EB) were determined according to the following formulas respectively. Ac(TB)(%) = (Tensile break point stress (TB) after the heat aging test - Tensile break point stress (TB) before the heat aging test) / Tensile break point stress (TB) before the heat aging test × 100 Ac(EB)(%) = (Tensile break point elongation (EB) after the heat aging test - Tensile break point elongation (EB) before the heat aging test) / Tensile break point elongation (EB) before the heat aging test × 100 For example, Ac(TB)(%) of Example 1 was determined as follows. Ac(TB)(%) of Example 1=(14.2 - 15.4) / 14.2×100 ≒ - 9 When the value of the change rate Ac(TB) of the tensile break point stress is - 10% or more and AH is 15 or less, it can be said that the heat aging resistance is excellent.

[0106] <<DIN Abrasion Test (Abrasion Amount)>> The abrasion resistance of the cross - linked sheet was tested by the DIN abrasion test in accordance with JIS K6264―2:2005. First, three cross - linked sheets with a thickness of 2 mm were stacked to prepare a disk - shaped test piece with a diameter of 16.0 ± 0.2 mm and a thickness of 6 mm. Then, for this test piece, using a DIN abrasion tester, a drum with a diameter of 150.0 ± 0.2 mm and a length of 500 mm was rotated at 40 revolutions per minute, and with a load of 1 kgf, the abrasion amount (DIN abrasion amount: unit mm 3 ) was measured when the abrasion distance was 40.0 ± 0.2 mm 3 When the DIN abrasion amount is 160 mm

[0107] <<Peel Strength>> The adhesion between the layer [I] containing the ethylene copolymer composition and the layer [II] containing the fibrous material in the crosslinked sheet was evaluated by the following method. A 3 mm thick uncrosslinked sheet prepared as described below was placed on a woven fabric of RFL-treated nylon fiber (manufactured by Ayaha Kogyo Co., Ltd.) and crosslinked by applying pressure at 170°C for 15 minutes using a 200-ton press molding machine to obtain a laminate (crosslinked sheet). A 25 mm wide test piece was punched out from the laminate, and a T-peel test was performed on this test piece at a tensile speed of 50 mm / min to determine the peel strength (adhesion strength) (N / cm). The peel test was performed three times, and the arithmetic average value was taken as the peel strength. An adhesive strength of 120 N / cm or higher can be said to indicate excellent adhesion to the layer containing the fiber material.

[0108] Example 1 50 parts by mass of ethylene copolymer (L-1) and 50 parts by mass of ethylene copolymer (L-2) were masticated for 30 seconds, and the masticated ethylene copolymer was mixed with 5 parts by mass of zinc oxide [trade name: Zinc Oxide Type 2, manufactured by Hakusui Tech Co., Ltd.] as a crosslinking aid, 1 part by mass of stearic acid as a processing aid, 2 parts by mass of tetrakis[methylene(3,5-di-t-butyl-4-hydroxy)hydrocinnamate]methane (trade name: Irganox 1010, manufactured by BASF Japan Ltd.) as antiaging agent 1, 4 parts by mass of 2-mercaptobenzimidazole (trade name: Sandant MB, manufactured by Sanshin Chemical Industry Co., Ltd.) as antiaging agent 2, 40 parts by mass of carbon black (manufactured by Asahi Carbon Co., Ltd., trade name: Asahi #70), and silica (trade name: ULTRASIL Ten parts by weight of trans-polyoctenylene (VN2, manufactured by Evonik Japan Co., Ltd.), 5 parts by weight of trans-polyoctenylene (M) (manufactured by Evonik Industries, trade name: VESTENAMER 8012), and 10 parts by weight of a softener (product name: Diana Process Oil PW-380, manufactured by Idemitsu Kosan Co., Ltd.) were mixed in a 1.7-liter Banbury mixer (manufactured by Kobe Steel, Ltd.) for 2 minutes. The ram was then raised and cleaned, and the mixture was mixed for an additional minute and then discharged at approximately 150°C to obtain a copolymer composition (Composition 1). This mixing was performed at a filling rate of 70%. Next, 86 parts by mass of this (Mixture-1) was wound around an 8-inch roll (surface temperature of front roll: 50°C, surface temperature of rear roll: 50°C, rotation speed of front roll: 16 rpm, rotation speed of rear roll: 18 rpm), and 8.5 parts by mass of dicumyl peroxide (manufactured by Kayaku Akzo Co., Ltd., trade name: Mitsui DCP-40C) was added as an organic peroxide and kneaded for 10 minutes to obtain a copolymer composition (Mixture-2).Then, these were cut into sheets according to the test pieces, and uncrosslinked sheets with thicknesses of 2 mm and 3 mm were prepared. The resulting 2 mm-thick uncrosslinked sheet was pressed at 170°C for 15 minutes using a 100-ton press to produce a crosslinked sheet. The physical properties of the resulting uncrosslinked and crosslinked sheets were measured using the methods described above. The results are shown in Table 1.

[0109] Comparative Example 1 An uncrosslinked copolymer composition was prepared in the same manner as in Example 1, except that the amount of ethylene copolymer (L-1) used in Example 1 was changed from 50 parts by mass to 100 parts by mass, the ethylene copolymer (L-2) was not used, and the amount of dicumyl peroxide was changed to 6.8 parts by mass. The copolymer composition was crosslinked to produce a laminate (crosslinked sheet). The physical properties of the obtained uncrosslinked and crosslinked sheets were evaluated by the methods described above. The results are shown in Table 1.

[0110] Comparative Example 2 An uncrosslinked copolymer composition was prepared in the same manner as in Example 1, except that the ethylene copolymer (L-1) used in Example 1 was not used and the amount of ethylene copolymer (L-2) was changed from 50 parts by mass to 100 parts by mass, and the copolymer composition was crosslinked to produce a laminate (crosslinked sheet). The physical properties of the obtained uncrosslinked and crosslinked sheets were evaluated by the methods described above. The results are shown in Table 1.

[0111] [Table 1]

[0112] It can be seen that the crosslinked sheet of Example 1 has superior adhesion to the layer containing a fiber material, and also has an excellent balance between heat aging resistance and abrasion resistance, compared to the crosslinked sheets of Comparative Examples 1 and 2.

Claims

1. an ethylene / α-olefin / non-conjugated polyene copolymer (L-1) having a structural unit derived from ethylene (A), a structural unit derived from an α-olefin (B) having 4 to 20 carbon atoms, and a structural unit derived from a non-conjugated polyene (C) containing, in one molecule, two or more partial structures selected from the group consisting of the following general formulas (I) and (II); an ethylene / α-olefin copolymer (L-2) other than the copolymer (L-1) containing a structural unit derived from ethylene and a structural unit derived from an α-olefin having 3 to 20 carbon atoms; trans polyoctenylene (M), 1. A copolymer composition for a conveyor belt, comprising: 【Chemistry 1】

2. The copolymer composition for a conveyor belt according to claim 1, wherein the ethylene / α-olefin / non-conjugated polyene copolymer (L-1) satisfies the following requirements (1) to (3): Requirement (1): The ratio [A] / [B] of the number of moles of structural units derived from ethylene (A) to the number of moles [B] of structural units derived from an α-olefin having 4 to 20 carbon atoms is 40 / 60 to 90 / 10; Requirement (2): The content ratio of the number of moles [C] of the structural unit derived from the non-conjugated polyene (C) is 0.1 to 6.0 mol % relative to 100 mol % in total of the structural units [A], [B], and [C]; Requirement (3): The B value represented by the following formula (i) is 1.20 or more. B value = ([EX] + 2[Y]) / [2 × [E] × ([X] + [Y])] ... formula (i) [Here, [E], [X], and [Y] represent the molar fractions of structural units derived from ethylene [A], an α-olefin having 4 to 20 carbon atoms [B], and a non-conjugated polyene [C], respectively, and [EX] represents the ethylene [A]-α-olefin having 4 to 20 carbon atoms [B] dyad chain fraction.]

3. 2. The copolymer composition for a conveyor belt according to claim 1, wherein the structural unit derived from the α-olefin (B) having 4 to 20 carbon atoms is a structural unit derived from 1-butene.

4. 2. The copolymer composition for a conveyor belt according to claim 1, wherein the structural unit derived from the non-conjugated polyene (C) is a structural unit derived from 5-vinyl-2-norbornene (VNB).

5. 2. The copolymer composition for a conveyor belt according to claim 1, wherein the content of structural units derived from ethylene in the ethylene-α-olefin copolymer (L-2) is 30 to 70 mass% based on all structural units constituting the copolymer (L-2).

6. 2. The copolymer composition for a conveyor belt according to claim 1, wherein the content of the trans polyoctenylene (M) is 0.5 to 50 parts by mass per 100 parts by mass of the ethylene-α-olefin-non-conjugated polyene copolymer (L-1) and the ethylene-α-olefin copolymer (L-2) combined.

7. The copolymer composition for a conveyor belt according to claim 1, further comprising an organic peroxide.

8. A conveyor belt comprising: a layer [I] containing the copolymer composition for a conveyor belt according to any one of claims 1 to 7; and a layer [II] containing a fibrous material, A laminate in which the layer [I] and the layer [II] are in contact with each other.

9. The laminate according to claim 8, wherein the layer [I] is the outermost layer.

10. The laminate according to claim 8, wherein the layer [I] is a crosslinked product of a copolymer composition for a conveyor belt.

11. The laminate according to claim 8, wherein the fibrous material of the layer [II] comprises RFL-treated fibers.

12. The laminate according to claim 8, wherein the fiber material of the layer [II] is canvas.

13. An industrial belt comprising the laminate of claim 8.

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