Ethylene copolymer composition for fuel cell gasket, fuel cell gasket made of the composition

Abstract

To provide an ethylene copolymer composition for a fuel cell gasket which is improved in fluidity, vulcanization rate, and durability such as thermal aging resistance.SOLUTION: The present invention relates to an ethylene copolymer composition for a fuel cell gasket which contains: 0-50 pts. mass of an ethylene / α-olefin / nonconjugated polyene copolymer (S) which has constituent units derived from ethylene (A), a C3-20 α-olefin (B), and a nonconjugated polyene (C) containing two or more partial structures selected from a group consisting of following general formulae (1) and (II) in total in a molecule and satisfies specific requirements; and 100-50 pts. mass of an ethylene / α-olefin / nonconjugated polyene copolymer (A) which has a structural unit derived from ethylene [A1], a structural unit derived from a C4-20 α-olefin [A2], and a structural unit derived from a nonconjugated polyene [A3] and satisfies specific requirements [provided that the total of the copolymer (S) and the copolymer (A) is 100 pts. mass].SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to an ethylene copolymer composition for a fuel cell gasket and its use.

Background Art

[0002] Ethylene-α-olefin copolymer elastomers such as ethylene-propylene copolymer (EPM, EPR) and ethylene-propylene-diene copolymer (EPDM) do not have unsaturated bonds in the main chain of their molecular structure. Therefore, compared with general-purpose conjugated diene rubbers, they are excellent in heat aging resistance, weather resistance, and ozone resistance, and are widely used in applications such as automotive parts, wire materials, electronic and electrical parts, building and civil engineering materials, and industrial material parts.

[0003] It is known to obtain a rubber molded body for sealing using EPDM (for example, Patent Document 1). The seal packing, which is a rubber molded body for sealing, is used in various applications such as automobiles, industrial machines, and electronic parts. However, since automobiles and industrial machines are used even in cold regions, the seal packing is required to have low-temperature characteristics in addition to mechanical strength at normal temperature.

[0004] Further, Patent Document 2 proposes an ethylene copolymer composition for a fuel cell gasket capable of forming a seal packing that achieves both low-temperature characteristics and mechanical strength (strength and elongation). The ethylene copolymer composition for a fuel cell gasket contains an ethylene-α-olefin-non-conjugated polyene copolymer containing a structural unit derived from ethylene [A] with a B value of 1.20 or more, 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].

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0006] The fuel cell gasket of a fuel cell vehicle (FCV) is a rubber component that prevents leakage of hydrogen, oxygen, and water in the FC stack. In addition to low-temperature characteristics, excellent durability is required. Further, there is a demand for a composition for a fuel cell gasket that can improve fluidity and shorten the vulcanization time for further productivity improvement.

[0007] An object of the present invention is to obtain an ethylene copolymer composition for a fuel cell gasket with improved durability such as fluidity, vulcanization rate, and heat aging resistance.

Means for Solving the Problems

[0008] The present invention has structural units derived from ethylene (A), an α-olefin (B) having 3 to 20 carbon atoms, and a non-conjugated polyene (C) containing two or more partial structures selected from the group consisting of the following general formulas (I) and (II) in the molecule, and satisfies the following requirements (i) to (vi): 100 to 20 parts by mass of an ethylene·α-olefin·non-conjugated polyene copolymer (S), 0 to 80 parts by mass of an ethylene·α-olefin·non-conjugated polyene copolymer (A) having a structural unit derived from ethylene [A1], a structural unit derived from an α-olefin [A2] having 4 to 20 carbon atoms, and a structural unit derived from a non-conjugated polyene [A3], and satisfying the following requirements (1) to (3) (wherein the total of the copolymer (S) and the copolymer (A) is 100 parts by mass). The present invention relates to an ethylene copolymer composition for a fuel cell gasket.

[0009]

Chemical Formula

[0010] 〔Requirements for the ethylene·α-olefin·non-conjugated polyene copolymer (S)〕 (i) The molar ratio [(A) / (B)] of the structural unit derived from ethylene (A) to the structural unit derived from α-olefin (B) is from 40 / 60 to 99.9 / 0.1; (ii) The mass fraction of the structural unit derived from non-conjugated polyene (C) is from 0.07% by mass to 10% by mass in 100% by mass of the copolymer (S); (iii) The weight-average molecular weight (Mw) of the copolymer (S), the weight fraction of the structural unit derived from non-conjugated polyene (C) (weight fraction of (C) (% by weight)), and the molecular weight of non-conjugated polyene (C) (molecular weight of (C)) satisfy the following formula (1); 4.5 ≤ Mw × (mass fraction of (C) / 100) / (molecular weight of (C)) ≤ 40 ··· Formula (1) (iv) The ratio P (η*(ω = 0.1) / η*(ω = 100)) of the complex viscosity η*(ω = 0.1) (Pa·sec) at a frequency ω = 0.1 rad / s to the complex viscosity η*(ω = 100) (Pa·sec) at a frequency ω = 100 rad / s, obtained by linear viscoelastic measurement (190°C) using a rheometer, the intrinsic viscosity [η], and the mass fraction of the structural unit derived from the non-conjugated polyene (C) (mass fraction of (C)) satisfy the following formula (2); P / ([η] 2.9 ) ≤ (mass fraction of (C)) × 6 ··· Formula (2) (v) The ratio (molecular weight distribution; Mw / Mn) of the weight-average molecular weight (Mw) to the number-average molecular weight (Mn), measured by gel permeation chromatography (GPC), is in the range of 4 to 80; (vi) The number-average molecular weight (Mn) is 30,000 or less.

[0011] [Requirements for ethylene·α-olefin·non-conjugated polyene copolymer (A)] (1) The molar ratio {[A1] / [A2]} of the structural unit derived from ethylene [A1] to the structural unit derived from an α-olefin having 4 to 20 carbon atoms [A2] is from 40 / 60 to 90 / 10, (2) The content ratio of the structural unit derived from non-conjugated polyene [A3] is from 0.1 to 6.0 mol% based on 100 mol% of the total of the structural units derived from [A1], [A2], and [A3], (3) The B value represented by the following formula (i) is 1.20 or more. B value = ([EX] + 2[Y]) / {2 × [E] × ([X] + [Y])} ··· (i) [Here, [E], [X], and [Y] respectively represent the molar fractions of structural units derived from ethylene [A1], α-olefin [A2] having 4 to 20 carbon atoms, and non-conjugated polyene [A3], and [EX] represents the ethylene [A1]-α-olefin [A2] having 4 to 20 carbon atoms diad chain fraction.]

Advantages of the Invention

[0012] The ethylene copolymer composition for fuel cell gaskets of the present invention has a fast crosslinking rate (vulcanization rate) and good fluidity. The fuel cell gasket obtained by crosslinking the copolymer composition has excellent compression set and heat aging resistance, so that the productivity and product durability (long life) in manufacturing fuel cell gaskets can be improved.

Embodiments for Carrying Out the Invention

[0013] <Ethylene·α-olefin·non-conjugated polyene copolymer (S)> The ethylene·α-olefin·non-conjugated polyene copolymer (S) [hereinafter may be abbreviated as "copolymer (S)"] which is the main component of the ethylene copolymer composition for fuel cell gaskets of the present invention has constituent units derived from ethylene (A), α-olefin (B) having 3 to 20 carbon atoms, and non-conjugated polyene (C) containing two or more substructures selected from the group consisting of the following general formulas (I) and (II) in total in the molecule, and is an ethylene·α-olefin·non-conjugated polyene copolymer satisfying the following requirements (i) to (vi).

[0014]

Chemical formula

[0015] (i) The molar ratio [(A) / (B)] of the structural unit derived from ethylene (A) to the structural unit derived from α-olefin (B) is from 40 / 60 to 99.9 / 0.1; (ii) The mass fraction of the structural unit derived from non-conjugated polyene (C) is from 0.07% by mass to 10% by mass in 100% by mass of the copolymer (S); (iii) The weight-average molecular weight (Mw) of the copolymer (S), the weight fraction of the structural unit derived from non-conjugated polyene (C) (weight fraction of (C) (% by weight)), and the molecular weight of non-conjugated polyene (C) (molecular weight of (C)) satisfy the following formula (1); (iv) The ratio P (η*(ω = 0.1) / η*(ω = 100)) of the complex viscosity η*(ω = 0.1) (Pa·sec) at a frequency ω = 0.1 rad / s to the complex viscosity η*(ω = 100) (Pa·sec) at a frequency ω = 100 rad / s obtained by linear viscoelastic measurement (190 °C) using a rheometer, the intrinsic viscosity [η], and the mass fraction of the structural unit derived from the non-conjugated polyene (C) (mass fraction of (C)) satisfy the following formula (2); 4.5 ≦ Mw × (mass fraction of (C) / 100) / (molecular weight of (C)) ≦ 40 ··· Formula (1) (v) The ratio (molecular weight distribution; Mw / Mn) of the weight-average molecular weight (Mw) to the number-average molecular weight (Mn) measured by gel permeation chromatography (GPC) is in the range of 4 to 80; P / ([η] 2.9 ) ≦ (mass fraction of (C)) × 6 ··· Formula (2) (vi) The number-average molecular weight (Mn) is 30,000 or less. (vii) The copolymer (S) according to the present invention may have a structural unit derived from a non-conjugated polyene (D) that contains only one substructure selected from the group consisting of the above general formulas (I) and (II) in the molecule in addition to the structural units derived from the above (A), (B), and (C).

[0016]

[0017] ​Examples of the α-olefin (B) having 3 to 20 carbon atoms include propylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-heptene, 1-octene, 1-decene, 1-dodecene, 1-tetradecene, 1-hexadecene, 1-eicosene and the like. Among these, α-olefins having 3 to 8 carbon atoms such as propylene, 1-butene, 1-hexene and 1-octene are preferable, and propylene is particularly preferable. Such α-olefins are preferable because the raw material cost is relatively low, the obtained ethylene·α-olefin·non-conjugated polyene copolymer exhibits excellent mechanical properties, and a molded article having rubber elasticity can be obtained. These α-olefins may be used alone or in combination of two or more.

[0018] The copolymer (S) according to the present invention contains a structural unit derived from at least one α-olefin (B) having 3 to 20 carbon atoms, and may contain structural units derived from two or more α-olefins (B) having 3 to 20 carbon atoms.

[0019] Examples of the non-conjugated polyene (C) containing two or more partial structures selected from the group consisting of the above general formulas (I) and (II) in the molecule include 5-vinyl-2-norbornene (VNB), norbornadiene, 1,4-hexadiene, dicyclopentadiene and the like. Among these, it is preferable that the non-conjugated polyene (C) contains VNB because of high availability, good hydrosilylation crosslinking, and easy improvement of the heat resistance of the polymer composition, and it is more preferable that the non-conjugated polyene (C) is VNB. The non-conjugated polyene (C) may be used alone or in combination of two or more.

[0020] The copolymer (S) according to the present invention may further contain a structural unit derived from a non-conjugated polyene (D) containing only one partial structure selected from the group consisting of the above general formulas (I) and (II) in the molecule, in addition to the structural units derived from ethylene (A), the α-olefin (B) having 3 to 20 carbon atoms and the non-conjugated polyene (C).

[0021] 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, ENB is preferred because it is easily available, the crosslinking rate during hydrosilylation is easy to control, and good mechanical properties are easily obtained. The non-conjugated polyene (D) may be used alone or in combination of two or more.

[0022] When the copolymer (S) according to the present invention contains a structural unit derived from a non-conjugated polyene (D) that contains only one substructure selected from the group consisting of the general formulas (I) and (II) in the molecule, the ratio is not particularly limited as long as the object of the present invention is not impaired, but usually, it is contained at a mass fraction of 0 to 20% by mass, preferably 0 to 8% by mass, more preferably about 0.01 to 8% by mass (however, the total mass fraction of (A), (B), (C), and (D) is 100% by mass).

[0023] 〈Requirement (i)〉 Requirement (i) specifies that the molar ratio of ethylene / α-olefin in the copolymer (S) according to the present invention satisfies 40 / 60 to 99.9 / 0.1, and this molar ratio preferably satisfies 50 / 50 to 90 / 10, more preferably 55 / 45 to 85 / 15, and even more preferably 55 / 45 to 78 / 22. The ethylene copolymer composition for fuel cell gaskets containing the ethylene·α-olefin·non-conjugated polyene copolymer (S) according to the present invention is crosslinked to obtain a fuel cell gasket that exhibits excellent rubber elasticity and is excellent in mechanical strength and heat aging resistance, so it is preferable.

[0024] In addition, the amount of ethylene (content of the structural unit derived from ethylene (A)) and the amount of α-olefin (content of the structural unit derived from α-olefin (B)) in the ethylene·α-olefin·non-conjugated polyene copolymer (S) can be 13 determined by C-NMR.

[0025] 〈Requirement (ii)〉 Requirement (ii) specifies that in the ethylene·α-olefin·non-conjugated polyene copolymer (S) according to the present invention, the mass fraction of the structural unit derived from the non-conjugated polyene (C) is in the range of 0.07 to 10% by mass in 100% by mass of the ethylene·α-olefin·non-conjugated polyene copolymer (S) (that is, in the total mass fraction of all structural units of 100% by mass). The mass fraction of the structural unit derived from this non-conjugated polyene (C) is preferably 0.1 to 8.0% by mass, and more preferably 0.5 to 5.0% by mass.

[0026] When the copolymer (S) according to the present invention satisfies requirement (ii), the ethylene copolymer composition for fuel cell gaskets according to the present invention has good fluidity and vulcanization rate, and the obtained fuel cell gasket exhibits excellent rubber elasticity and is excellent in mechanical strength and heat aging resistance, so it is preferable. In addition, the amount of non-conjugated polyene (C) (content of the structural unit derived from non-conjugated polyene (C)) in the copolymer (S) can be 13 determined by C-NMR.

[0027] <Requirement (iii)> Requirement (iii) specifies that in the copolymer (S) according to the present invention, the weight-average molecular weight (Mw) of the ethylene·α-olefin·non-conjugated polyene copolymer, the mass fraction of the structural unit derived from the non-conjugated polyene (C) in the copolymer ((mass fraction of (C): mass %), and the molecular weight of the non-conjugated polyene (C) ((molecular weight of (C)) satisfy the following relational expression (1). 4.5 ≦ Mw × (mass fraction of (C) / 100) / (molecular weight of (C)) ≦ 40 ··· Formula (1)

[0028] When the copolymer (S) according to the present invention satisfies Requirement (iii), the content of the structural unit derived from the non-conjugated polyene (C) such as VNB is appropriate, and when a fuel cell gasket is manufactured using the ethylene copolymer composition for fuel cell gaskets according to the present invention, it is preferable because it has excellent crosslinking speed and the fuel cell gasket after crosslinking exhibits excellent mechanical properties.

[0029] More preferably, the copolymer (S) according to the present invention desirably satisfies the following relational expression (1'). 4.5 ≦ Mw × (mass fraction of (C) / 100) / (molecular weight of (C)) ≦ 35 ··· Formula (1') The weight-average molecular weight (Mw) of the copolymer (S) can be determined as a polystyrene-equivalent value measured by gel permeation chromatography (GPC).

[0030] When the "Mw × (mass fraction of (C) / 100) / (molecular weight of (C))" of the copolymer (S) according to the present invention satisfies the above formula (1) or (1'), the degree of crosslinking is appropriate, and by using this, a fuel cell gasket excellent in mechanical physical properties and heat aging resistance can be manufactured in a well-balanced manner. When the "Mw × (mass fraction of (C) / 100) / (molecular weight of (C))" is too small, the crosslinkability may be insufficient and the crosslinking speed may become slow. When it is too large, excessive crosslinking may occur and the mechanical physical properties of the obtained fuel cell gasket may deteriorate.

[0031] <Requirement (iv)> Requirement (iv) specifies that the ratio P(η * ( ω =0.1) (Pa·sec) at a frequency ω = 0.1 rad / s and the complex viscosity η * ( ω =100) (Pa·sec) at a frequency ω = 100 rad / s of the copolymer (S) according to the present invention, the intrinsic viscosity [η], and the mass fraction of the structural unit derived from the non-conjugated polyene (C) ((mass fraction of (C): mass %) satisfy the following formula (2). * ( ω =0.1) / η * ( ω =100) ) is a measure of the frequency dependence of the viscosity, and P / ([η] P / ([η] 2.9 ) ≤ (mass fraction of (C)) × 6... Formula (2)

[0032] Here, the ratio P(η * ( ω =0.1) at a frequency ω = 0.1 rad / s and the complex viscosity η * ( ω =100) at a frequency ω = 100 rad / s represents the frequency dependence of the viscosity, and P / ([η] * ( ω =0.1) / η * ( ω =100) ) corresponds to the left side of formula (2). 2.9) shows a tendency to exhibit a high value when there are many long-chain branches, although there are influences such as short-chain branches and molecular weight. Generally, in an ethylene·α-olefin·non-conjugated polyene copolymer, the more constituent units derived from non-conjugated polyene it contains, the more likely it is to contain many long-chain branches. However, the copolymer (S) according to the present invention is considered to be able to satisfy the above formula (2) because it has fewer long-chain branches than a conventionally known ethylene·α-olefin·non-conjugated polyene copolymer. In the present invention, the P value was determined by measuring with a viscoelasticity measuring device Ares (manufactured by Rheometric Scientific) at 190 °C, a strain of 1.0%, and varying the frequency. The ratio (η* ratio) was obtained from the complex viscosity at 0.1 rad / s and the complex viscosity at 100 rad / s.

[0033] The copolymer (S) according to the present invention preferably satisfies the following formula (2'). P / ([η] 2.9 ) ≤ (mass fraction of (C)) × 5.7 ··· formula (2') Note that the intrinsic viscosity [η] means a value measured in decalin at 135 °C.

[0034] 〈Requirement (v)〉 The copolymer (S) according to the present invention has a ratio of weight-average molecular weight (Mw) to number-average molecular weight (Mn) (molecular weight distribution; Mw / Mn) measured by gel permeation chromatography (GPC) in the range of 4 to 80, preferably 3 to 70.

[0035] 〈Requirement (vi)〉 The copolymer (S) according to the present invention has the number-average molecular weight (Mn) in the range of 30,000 or less, preferably 200 to 28,000.

[0036] The copolymer (S) according to the present invention desirably has an intrinsic viscosity [η] preferably in the range of 0.1 to 5 dL / g, more preferably 0.5 to 5.0 dL / g, and even more preferably 0.7 to 4.0 dL / g.

[0037] <Production of ethylene·α-olefin·non-conjugated polyene copolymer (S)> The ethylene·α-olefin·non-conjugated polyene copolymer (S) according to the present invention is a copolymer obtained by copolymerizing a monomer composed of ethylene (A), an α-olefin (B) having 3 to 20 carbon atoms, a non-conjugated polyene (C) containing two or more substructures selected from the group consisting of the general formulas (I) and (II) in total in the molecule, and, if necessary, a non-conjugated polyene (D) containing only one substructure selected from the group consisting of the general formulas (I) and (II) in total in the molecule.

[0038] The copolymer (S) according to the present invention may be prepared by any production method as long as the above requirements (i) and (ii), preferably (iii) to (v) are satisfied, but it is preferably obtained by copolymerizing monomers in the presence of a metallocene compound, and more preferably obtained by copolymerizing monomers in the presence of a catalyst system containing a metallocene compound.

[0039] Specifically, the copolymer (S) according to the present invention can be produced, for example, by adopting the method described in the metallocene catalyst described in the pamphlet of International Publication No. 2015 / 122495.

[0040] <Ethylene·α-olefin·non-conjugated polyene copolymer (A)> The ethylene·α-olefin·non-conjugated polyene copolymer (A) [hereinafter, may be abbreviated as "copolymer (A)"] which is a subcomponent of the ethylene copolymer composition for a fuel cell gasket of the present invention contains a structural unit derived from ethylene [A], a structural unit derived from at least one α-olefin [B] having 4 to 20 carbon atoms, and a structural unit derived from at least one non-conjugated polyene [C], and satisfies the following requirements (1) to (4).

[0041] <Requirement (1)> The molar ratio [A] / [B] of the structural unit derived from ethylene [A] and the structural unit derived from α-olefin [B] is 40 / 60 to 90 / 10, <Requirement (2)> The content of the structural unit derived from the non-conjugated polyene [C] is 0.1 to 6.0 mol% based on the total of the structural units of [A], [B], and [C] being 100 mol%. 〈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])} ··· (i) [Here, [E], [X], and [Y] represent the molar fractions of 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 diad chain fraction.]

[0042] Examples of the α-olefin [B] having 4 to 20 carbon atoms include linear structures without side chains, starting from 1-butene having 4 carbon atoms, passing through 1-nonene having 9 carbon atoms and 1-decene having 10 carbon atoms, to 1-nonadecene having 19 carbon atoms, 1-eicosene having 20 carbon atoms, and 4-methyl-1-pentene, 9-methyl-1-decene, 11-methyl-1-dodecene, 12-ethyl-1-tetradecene, etc. having side chains.

[0043] These α-olefins [B] can be used alone or in combination of two or more. Among these, α-olefins having 4 to 10 carbon atoms are preferred, and particularly 1-butene, 1-hexene, 1-octene, etc. are preferred, and particularly 1-butene is suitable.

[0044] Ethylene·propylene·non-conjugated polyene copolymers in which the α-olefin is propylene have insufficient rubber elasticity at low temperatures, so their applications may be limited. On the other hand, ethylene·α-olefin·non-conjugated polyene copolymer (A) has a structural unit derived from the α-olefin [B] having 4 to 20 carbon atoms, so it has excellent rubber elasticity at low temperatures.

[0045] Examples of the non-conjugated polyene [C] include chain non-conjugated dienes such as 1,4-hexadiene, 1,6-octadiene, 2-methyl-1,5-hexadiene, 6-methyl-1,5-heptadiene, 7-methyl-1,6-octadiene; cyclic non-conjugated dienes such as cyclohexadiene, dicyclopentadiene, methyltetrahydroindene, 5-vinyl-2-norbornene, 5-ethylidene-2-norbornene, 5-methylene-2-norbornene, 5-isopropylidene-2-norbornene, 6-chloromethyl-5-isopropenyl-2-norbornene; and trienes such as 2,3-diisopropylidene-5-norbornene, 2-ethylidene-3-isopropylidene-5-norbornene, 2-propenyl-2,5-norbornadiene, 1,3,7-octatriene, 1,4,9-decatriene, 4,8-dimethyl-1,4,8-decatriene, 4-ethylidene-8-methyl-1,7-nonadiene.

[0046] These non-conjugated polyenes [C] can be used alone or in combination of two or more. Among these, chain non-conjugated dienes such as 1,4-hexadiene and cyclic non-conjugated dienes such as 5-ethylidene-2-norbornene, 5-vinyl-2-norbornene are preferred, and cyclic non-conjugated dienes are more preferred, with 5-ethylidene-2-norbornene and 5-vinyl-2-norbornene being particularly preferred.

[0047] Examples of the ethylene·α-olefin·non-conjugated polyene copolymer (A) according to the present invention include the following. Ethylene·1-butene·1,4-hexadiene copolymer, Ethylene·1-pentene·1,4-hexadiene copolymer, Ethylene·1-hexene·1,4-hexadiene copolymer, Ethylene·1-heptene·1,4-hexadiene copolymer, Ethylene·1-octene·1,4-hexadiene copolymer, Ethylene·1-nonene·1,4-hexadiene copolymer, Ethylene-1-decene-1,4-hexadiene copolymer, Ethylene-1-butene-1-octene-1,4-hexadiene copolymer, Ethylene-1-butene-5-ethylidene-2-norbornene copolymer, Ethylene-1-pentene-5-ethylidene-2-norbornene copolymer, Ethylene-1-hexene-5-ethylidene-2-norbornene copolymer, Ethylene-1-heptene-5-ethylidene-2-norbornene copolymer, Ethylene-1-octene-5-ethylidene-2-norbornene copolymer, Ethylene-1-nonene-5-ethylidene-2-norbornene copolymer, Ethylene-1-decene-5-ethylidene-2-norbornene copolymer, Ethylene-1-butene-1-octene-5-ethylidene-2-norbornene copolymer, Ethylene-1-butene-5-ethylidene-2-norbornene-5-vinyl-2-norbornene copolymer, Ethylene-1-pentene-5-ethylidene-2-norbornene-5-vinyl-2-norbornene copolymer, Ethylene-1-hexene-5-ethylidene-2-norbornene-5-vinyl-2-norbornene copolymer, Ethylene-1-heptene-5-ethylidene-2-norbornene-5-vinyl-2-norbornene copolymer, Ethylene-1-octene-5-ethylidene-2-norbornene-5-vinyl-2-norbornene copolymer, Ethylene-1-nonene-5-ethylidene-2-norbornene-5-vinyl-2-norbornene copolymer, Ethylene-1-decene-5-ethylidene-2-norbornene-5-vinyl-2-norbornene copolymer, Ethylene-1-butene-1-octene-5-ethylidene-2-norbornene-5-vinyl-2-norbornene copolymer.

[0048] The ethylene·α-olefin·non-conjugated polyene copolymer (A) is used in one kind or two or more kinds as necessary.

[0049] 〈Requirement (1)〉 The molar ratio [[A] / [B]] of the structural unit derived from ethylene [A] and the structural unit derived from α-olefin [B] is in the range of 40 / 60 to 90 / 10, preferably 40 / 60 to 80 / 20, more preferably 45 / 55 to 70 / 30, and particularly preferably 50 / 50 to 70 / 30. When the molar ratio of the structural unit derived from ethylene [A] and the structural unit derived from α-olefin [B] is in the above range, an ethylene-based copolymer excellent in the balance between rubber elasticity at low temperature and tensile strength at normal temperature can be obtained.

[0050] 〈Requirement (2)〉 The content of the structural unit derived from non-conjugated polyene [C] is in the range of 0.1 to 6.0 mol%, preferably 0.1 to 4.0 mol%, more preferably 0.5 to 3.0 mol%, based on 100 mol% of the total of the structural units of [A], [B], and [C]. When the structural unit derived from non-conjugated polyene [C] is in the above range, an ethylene-based copolymer having sufficient crosslinkability and flexibility can be obtained.

[0051] 〈Requirement (3)〉 The B value is 1.20 or more, preferably in the range of 1.20 to 1.80, and particularly preferably in the range of 1.22 to 1.40. An ethylene-based copolymer with a B value of less than 1.20 may have a large compression set at low temperature, and it may not be possible to obtain an ethylene-based copolymer excellent in the balance between rubber elasticity at low temperature and tensile strength at normal temperature.

[0052] The B value is an index indicating the randomness of the copolymer monomer chain distribution in the copolymer. [E], [X], [Y], and [EX] in the above formula (i) are 13The 13C-NMR spectrum is measured and can be determined based on the reports of J. C. Randall [Macromolecules, 15, 353 (1982)], J. Ray [Macromolecules, 10, 773 (1977)], etc.

[0053] The ethylene·α-olefin·non-conjugated polyene copolymer (A) according to the present invention preferably has a Mooney viscosity ML at 100 °C (1+4) 100 is in the range of 5 to 100, more preferably 10 to 90, and particularly preferably 10 to 70.

[0054] When the Mooney viscosity is in the above range, an ethylene·α-olefin·non-conjugated polyene copolymer (A) showing good post-treatment (ribbon handling property) and having excellent rubber physical properties can be obtained.

[0055] <<Manufacturing Method of Ethylene·α-Olefin·Non-Conjugated Polyene Copolymer (A)>> The copolymer (A) according to the present invention can be obtained by the following manufacturing method. Specifically, in the presence of an olefin polymerization catalyst containing (a) a transition metal compound represented by the following general formula [I] (hereinafter also referred to as "bridged metallocene compound") and (b) at least one compound selected from (b-1) an organometallic compound, (b-2) an organoaluminum oxy compound, and (b-3) a compound that reacts with the transition metal compound (a) to form an ion pair, ethylene, an α-olefin having 4 to 20 carbon atoms, and a non-conjugated polyene are copolymerized.

[0056] [Chemical formula]

[0057] (In formula [I], Y is selected from a carbon atom, a silicon atom, a germanium atom, and a tin atom, M is a titanium atom, a zirconium atom, or a hafnium atom, R 1 、R 2 、R3 , R 4 , R 5 and R 6 are each an atom or substituent selected from a hydrogen atom, a hydrocarbon group having 1 to 20 carbon atoms, an aryl group, a substituted aryl group, a silicon-containing group, a nitrogen-containing group, an oxygen-containing group, a halogen atom, and a halogen-containing group, and may be the same or different from each other. R 1 from R 6 to R Q is selected from a halogen atom, a hydrocarbon group having 1 to 20 carbon atoms, an anionic ligand, and a neutral ligand capable of coordinating with a lone pair in the same or different combinations. n is an integer of 1 to 4. j is an integer of 1 to 4.)

[0058] <Crosslinked metallocene compound (a)> The crosslinked metallocene compound (a) is represented by the above general formula [I]. Y, M, R 1 ~R 6 , Q, and j will be described below.

[0059] (Y, M, R 1 ~R 6 , Q, n, and j) Y is selected from a carbon atom, a silicon atom, a germanium atom, and a tin atom, preferably a carbon atom.

[0060] M is a titanium atom, a zirconium atom, or a hafnium atom, preferably a hafnium atom.

[0061] R 1 , R 2 , R 3 , R 4 , R 5 and R 6 are each an atom or substituent selected from a hydrogen atom, a hydrocarbon group having 1 to 20 carbon atoms, an aryl group, a substituted aryl group, a silicon-containing group, a nitrogen-containing group, an oxygen-containing group, a halogen atom, and a halogen-containing group, and may be the same or different from each other. Also, R 1From R 6 The adjacent substituents from R to R may be bonded to each other to form a ring, or may not be bonded to each other.

[0062] Here, examples of the hydrocarbon group having 1 to 20 carbon atoms include an alkyl group having 1 to 20 carbon atoms, a cyclic saturated hydrocarbon group having 3 to 20 carbon atoms, a chain unsaturated hydrocarbon group having 2 to 20 carbon atoms, and a cyclic unsaturated hydrocarbon group having 3 to 20 carbon atoms. Also, R 1 From R 6 When the adjacent substituents from R to R are bonded to each other to form a ring, examples thereof include an alkylene group having 1 to 20 carbon atoms and an arylene group having 6 to 20 carbon atoms.

[0063] Examples of the alkyl group having 1 to 20 carbon atoms include a methyl group, an ethyl group, an n-propyl group, an n-butyl group, an n-pentyl group, an n-hexyl group, an n-heptyl group, an n-octyl group, an n-nonyl group, an n-decanyl group, etc., which are linear saturated hydrocarbon groups, and an isopropyl group, an isobutyl group, an s-butyl group, a t-butyl group, a t-amyl group, a neopentyl group, a 3-methylpentyl group, a 1,1-diethylpropyl group, a 1,1-dimethylbutyl group, a 1-methyl-1-propylbutyl group, a 1,1-dipropylbutyl group, a 1,1-dimethyl-2-methylpropyl group, a 1-methyl-1-isopropyl-2-methylpropyl group, a cyclopropylmethyl group, etc., which are branched saturated hydrocarbon groups. The number of carbon atoms of the alkyl group is preferably 1 to 6.

[0064] Examples of the cyclic saturated hydrocarbon group having 3 to 20 carbon atoms include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, a norbornenyl group, a 1-adamantyl group, a 2-adamantyl group, etc., which are cyclic saturated hydrocarbon groups, and a 3-methylcyclopentyl group, a 3-methylcyclohexyl group, a 4-methylcyclohexyl group, a 4-cyclohexylcyclohexyl group, a 4-phenylcyclohexyl group, etc., which are groups in which a hydrogen atom of the cyclic saturated hydrocarbon group is replaced by a hydrocarbon group having 1 to 17 carbon atoms. The number of carbon atoms of the cyclic saturated hydrocarbon group is preferably 5 to 11.

[0065] Examples of chain unsaturated hydrocarbon groups having 2 to 20 carbon atoms include alkenyl groups such as ethenyl group (vinyl group), 1-propenyl group, 2-propenyl group (allyl group), 1-methylethenyl group (isopropenyl group), and alkynyl groups such as ethynyl group, 1-propynyl group, 2-propynyl group (propargyl group). The number of carbon atoms in the chain unsaturated hydrocarbon group is preferably 2 to 4.

[0066] Examples of cyclic unsaturated hydrocarbon groups having 3 to 20 carbon atoms include cyclic unsaturated hydrocarbon groups such as cyclopentadienyl group, norbornyl group, phenyl group, naphthyl group, indenyl group, azulenyl group, phenanthryl group, anthracenyl group, and groups in which a hydrogen atom of a cyclic unsaturated hydrocarbon group is replaced by a hydrocarbon group having 1 to 15 carbon atoms, such as 3-methylphenyl group (m-tolyl group), 4-methylphenyl group (p-tolyl group), 4-ethylphenyl group, 4-t-butylphenyl group, 4-cyclohexylphenyl group, biphenylyl group, 3,4-dimethylphenyl group, 3,5-dimethylphenyl group, 2,4,6-trimethylphenyl group (mesityl group), and groups in which a hydrogen atom of a linear hydrocarbon group or a branched saturated hydrocarbon group is replaced by a cyclic saturated hydrocarbon group or a cyclic unsaturated hydrocarbon group having 3 to 19 carbon atoms, such as benzyl group, cumyl group. The number of carbon atoms in the cyclic unsaturated hydrocarbon group is preferably 6 to 10.

[0067] Examples of alkylene groups having 1 to 20 carbon atoms include methylene group, ethylene group, dimethylmethylene group (isopropylidene group), ethylmethylene group, 1-methylethylene group, 2-methylethylene group, 1,1-dimethylethylene group, 1,2-dimethylethylene group, n-propylene group. The number of carbon atoms in the alkylene group is preferably 1 to 6.

[0068] Examples of arylene groups having 6 to 20 carbon atoms include o-phenylene group, m-phenylene group, p-phenylene group, 4,4'-biphenylylene group. The number of carbon atoms in the arylene group is preferably 6 to 12.

[0069] Examples of the aryl group partly overlap with the examples of the cyclic unsaturated hydrocarbon group having 3 to 20 carbon atoms described above, and include a phenyl group, 1-naphthyl group, 2-naphthyl group, anthracenyl group, phenanthrenyl group, tetracenyl group, chrysenyl group, pyrenyl group, indenyl group, azulenyl group, pyrrolyl group, pyridyl group, furanyl group, thiophenyl group, etc., which are substituents derived from aromatic compounds. As the aryl group, a phenyl group or 2-naphthyl group is preferable.

[0070] Examples of the aromatic compound include benzene, naphthalene, anthracene, phenanthrene, tetracene, chrysene, pyrene, pyrene, indene, azulene, pyrrole, pyridine, furan, thiophene, etc., which are aromatic hydrocarbons and heterocyclic aromatic compounds.

[0071] Examples of the substituted aryl group partly overlap with the examples of the cyclic unsaturated hydrocarbon group having 3 to 20 carbon atoms described above, and include a group in which one or more hydrogen atoms of the aryl group are substituted with a substituent selected from a hydrocarbon group having 1 to 20 carbon atoms, aryl group, silicon-containing group, nitrogen-containing group, oxygen-containing group, halogen atom, and halogen-containing group. Specifically, 3-methylphenyl group (m-tolyl group), 4-methylphenyl group (p-tolyl group), 3-ethylphenyl group, 4-ethylphenyl group, 3,4-dimethylphenyl group, 3,5-dimethylphenyl group, biphenylyl group, 4-(trimethylsilyl)phenyl group, 4-aminophenyl group, 4-(dimethylamino)phenyl group, 4-(diethylamino)phenyl group, 4-morpholinylphenyl group, 4-methoxyphenyl group, 4-ethoxyphenyl group, 4-phenoxyphenyl group, 3,4-dimethoxyphenyl group, 3,5-dimethoxyphenyl group, 3-methyl-4-methoxyphenyl group, 3,5-dimethyl-4-methoxyphenyl group, 3-(trifluoromethyl)phenyl group, 4-(trifluoromethyl)phenyl group, 3-chlorophenyl group, 4-chlorophenyl group, 3-fluorophenyl group, 4-fluorophenyl group, 5-methylnaphthyl group, 2-(6-methyl)pyridyl group, etc. are exemplified. Further, as the substituted aryl group, an "electron-donating group-containing substituted aryl group" described later is also included.

[0072] Examples of the silicon-containing group include alkylsilyl groups such as trimethylsilyl group, triethylsilyl group, t-butyldimethylsilyl group, triisopropylsilyl group, etc., in which a carbon atom in a hydrocarbon group having 1 to 20 carbon atoms is replaced by a silicon atom; arylsilyl groups such as dimethylphenylsilyl group, methyldiphenylsilyl group, t-butyldiphenylsilyl group, etc.; pentamethyldisilanyl group; trimethylsilylmethyl group and the like. The number of carbon atoms in the alkylsilyl group is preferably 1 to 10, and the number of carbon atoms in the arylsilyl group is preferably 6 to 18.

[0073] Examples of the nitrogen-containing group include amino group, nitro group, N-morpholinyl group, and groups in which the =CH- structural unit in the above-mentioned hydrocarbon group having 1 to 20 carbon atoms or silicon-containing group is replaced by a nitrogen atom, groups in which the -CH2- structural unit is replaced by a nitrogen atom bonded with a hydrocarbon group having 1 to 20 carbon atoms, or groups in which the -CH3 structural unit is replaced by a nitrogen atom bonded with a hydrocarbon group having 1 to 20 carbon atoms or a nitrile group, such as dimethylamino group, diethylamino group, dimethylaminomethyl group, cyano group, pyrrolidinyl group, piperidinyl group, pyridinyl group, etc. Preferred nitrogen-containing groups are dimethylamino group and N-morpholinyl group.

[0074] Examples of the oxygen-containing group include a hydroxyl group, a hydrocarbon group having 1 to 20 carbon atoms, a silicon-containing group or a nitrogen-containing group described above, a group in which a -CH2- structural unit is replaced by an oxygen atom or a carbonyl group, or a methoxy group, an ethoxy group, a t-butoxy group, a phenoxy group, a trimethylsiloxy group, a methoxyethoxy group, a hydroxymethyl group, a methoxymethyl group, an ethoxymethyl group, a t-butoxymethyl group, a 1-hydroxyethyl group, a 1-methoxyethyl group, a 1-ethoxyethyl group, a 2-hydroxyethyl group, a 2-methoxyethyl group, a 2-ethoxyethyl group, an n-2-oxabutylene group, an n-2-oxapentylene group, an n-3-oxapentylene group, an aldehyde group, an acetyl group, a propionyl group, a benzoyl group, a trimethylsilylcarbonyl group, a carbamoyl group, a methylaminocarbonyl group, a carboxy group, a methoxycarbonyl group, a carboxymethyl group, an ethoxycarbonylmethyl group, a carbamoylmethyl group, a furanyl group, a pyranyl group, etc. As the oxygen-containing group, a methoxy group is preferable.

[0075] Examples of the halogen atom include fluorine, chlorine, bromine, iodine, etc., which are Group 17 elements. Examples of the halogen-containing group include a trifluoromethyl group, a tribromomethyl group, a pentafluoroethyl group, a pentafluorophenyl group, etc., which are groups in which a hydrogen atom is replaced by a halogen atom in the hydrocarbon group having 1 to 20 carbon atoms, the silicon-containing group, the nitrogen-containing group or the oxygen-containing group described above.

[0076] Q is selected from a halogen atom, a hydrocarbon group having 1 to 20 carbon atoms, an anionic ligand and a neutral ligand capable of coordinating with a lone pair of electrons in the same or different combinations. Details of the halogen atom and the hydrocarbon group having 1 to 20 carbon atoms are as described above. When Q is a halogen atom, a chlorine atom is preferable. When Q is a hydrocarbon group having 1 to 20 carbon atoms, the number of carbon atoms of the hydrocarbon group is preferably 1 to 7.

[0077] Examples of the anionic ligand include alkoxy groups such as methoxy group, t-butoxy group, and phenoxy group, carboxylate groups such as acetate and benzoate, and sulfonate groups such as mesylate and tosylate.

[0078] Examples of the neutral ligand capable of coordinating with an lone pair of electrons include organophosphorus compounds such as trimethylphosphine, triethylphosphine, triphenylphosphine, and diphenylmethylphosphine, and ether compounds such as tetrahydrofuran, diethyl ether, dioxane, and 1,2-dimethoxyethane.

[0079] n is an integer of 1 to 4. j is an integer of 1 to 4, preferably 2. Note that the above examples regarding the formula [I] are similarly applicable in the following description.

[0080] The 2,3,6,7-tetramethylfluorenyl group contained in the crosslinked metallocene compound (a) represented by the general formula [I] has four substituents at the 2, 3, 6, and 7 positions, so it has a large electronic effect. Thus, it is presumed that it has high polymerization activity and produces a high molecular weight ethylene·α-olefin·non-conjugated polyene copolymer (A). On the other hand, generally, non-conjugated polyene is bulkier than α-olefin. Therefore, it is presumed that the vicinity of the central metal of the metallocene compound, which is the polymerization catalyst, particularly the polymerization active site, should not be bulky for improving the copolymerization performance of non-conjugated polyene. The four methyl groups contained in the 2,3,6,7-tetramethylfluorenyl group are not bulkier than other hydrocarbon groups, etc., so this is considered to contribute to high non-conjugated polyene copolymerization performance. From the above, it is presumed that the crosslinked metallocene compound represented by the general formula [I] containing particularly the 2,3,6,7-tetramethylfluorenyl group simultaneously and well-balancedly realizes a high molecular weight, high non-conjugated polyene copolymerization performance, and high polymerization activity of the produced ethylene·α-olefin·non-conjugated polyene copolymer (A) at a high level.

[0081] In the crosslinked metallocene compound (a) represented by the above general formula [I], n is preferably 1. Such a crosslinked metallocene compound (a-1) is represented by the following general formula [V].

[0082]

Chemical formula

[0083] (In formula [V], the definitions of Y, M, R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , Q and j are as defined above.)

[0084] Compared with the compound in which n in the above general formula [I] is an integer of 2 to 4, the crosslinked metallocene compound (a-1) has a simplified manufacturing process, a reduced manufacturing cost, and ultimately, the manufacturing cost of the ethylene·α-olefin·non-conjugated polyene copolymer (A) can be reduced by using this crosslinked metallocene compound. Furthermore, when ethylene, an α-olefin having 4 or more carbon atoms, and a non-conjugated polyene are copolymerized in the presence of an olefin polymerization catalyst containing the crosslinked metallocene compound (a-1), the advantage of increasing the molecular weight of the resulting ethylene·α-olefin·non-conjugated polyene copolymer (A) can also be obtained.

[0085] In the crosslinked metallocene compound (a-1) represented by the above general formula [I], it is preferable that R 1 , R 2 , R 3 and R 4 are all hydrogen atoms. Such a crosslinked metallocene compound (a-2) is represented by the following general formula [VI].

[0086]

Chemical formula

[0087] (In formula [VI], Y, M, R 5 , R6 The definitions of Q and j are as described above.)

[0088] The bridged metallocene compound (a-2) has a simpler production process, lower production cost, and thus the production cost of the ethylene / α-olefin / non-conjugated polyene copolymer can be reduced by using this bridged metallocene compound, compared to a compound in which any one or more of R 1 , R 2 , R 3 and R 4 are substituted with substituents other than hydrogen atoms. Further, when ethylene, an α-olefin having 4 or more carbon atoms, and a non-conjugated polyene are copolymerized in the presence of an olefin polymerization catalyst containing the bridged metallocene compound (a-2), advantages such as improved polymerization activity and increased molecular weight of the resulting ethylene·α-olefin·non-conjugated polyene copolymer (A) can be obtained. At the same time, an advantage of improved copolymerization performance of the non-conjugated polyene can also be obtained.

[0089] In the bridged metallocene compound (a-2) represented by the above general formula [VI], it is more preferable that Y is a carbon atom. Such a bridged metallocene compound (a-3) is represented by the following general formula [VII].

[0090]

Chemical formula

[0091] (In formula [VII], the definitions of M, R 5 , R 6 , Q and j are as described above.) The bridged metallocene compound (a-3) can be synthesized by a simple method such as the following formula [VIII].

[0092]

Chemical formula

[0093] (In formula [VIII], M, R5 , R 6 is defined as described above.)

[0094] In the above formula [VIII], R 5 and R 6 are atoms or substituents selected from a hydrogen atom, a hydrocarbon group having 1 to 20 carbon atoms, an aryl group, a substituted aryl group, a silicon-containing group, a nitrogen-containing group, an oxygen-containing group, a halogen atom, and a halogen-containing group, which may be the same or different from each other, and may be bonded to each other to form a ring. However, for various ketones represented by the general formula R 5 -C(=O)-R 6 satisfying such conditions are commercially available from general reagent manufacturers, so the raw materials of the crosslinked metallocene compound (a-3) are easily available. Further, even if such a ketone is not commercially available, the ketone can be easily synthesized, for example, by the method by Olah et al. [Heterocycles, 40, 79 (1995)]. Thus, the crosslinked metallocene compound (a-3) has a simpler and easier manufacturing process compared to the compounds in which Y in the above general formula [V] is selected from a silicon atom, a germanium atom, and a tin atom, the manufacturing cost is further reduced, and ultimately, the manufacturing cost of the ethylene-based copolymer is reduced by using this crosslinked metallocene compound. Furthermore, when ethylene, an α-olefin having 4 or more carbon atoms, and a non-conjugated polyene are copolymerized in the presence of an olefin polymerization catalyst containing the crosslinked metallocene compound (a-3), an additional advantage of further increasing the molecular weight of the resulting ethylene·α-olefin·non-conjugated polyene copolymer (A) is obtained.

[0095] In the crosslinked metallocene compound (a-3) represented by the above general formula [VII], R 5 and R 6is preferably a group selected from an aryl group and a substituted aryl group. When ethylene, an α-olefin having 4 or more carbon atoms, and a non-conjugated polyene are copolymerized in the presence of an olefin polymerization catalyst containing the bridged metallocene compound, advantages such as further improvement in polymerization activity and further increase in the molecular weight of the produced ethylene·α-olefin·non-conjugated polyene copolymer (A) can be obtained. At the same time, an advantage of improving the copolymerization performance of the non-conjugated polyene can also be obtained.

[0096] In the bridged metallocene compound (a-3) represented by the above general formula [VII], R 5 and R 6 are more preferably the same group selected from an aryl group and a substituted aryl group. By selecting R 5 and R 6 in this way, the synthesis process of the bridged metallocene compound is simplified, the manufacturing cost is further reduced, and ultimately, the manufacturing cost of the ethylene-based copolymer can be reduced by using this bridged metallocene compound.

[0097] In the bridged metallocene compound (a-3) represented by the above general formula [VII], R 5 and R 6 are more preferably the same substituted aryl group. When ethylene, an α-olefin having 4 or more carbon atoms, and a non-conjugated polyene are copolymerized in the presence of an olefin polymerization catalyst containing the bridged metallocene compound, an advantage of further increasing the molecular weight of the produced ethylene·α-olefin·non-conjugated polyene copolymer (A) can be obtained.

[0098] In the bridged metallocene compound (a-3) represented by the above general formula [VII], R 5 and R 6is a substituted aryl group obtained by substituting one or more hydrogen atoms of an aryl group with an electron-donating substituent having a Hammett's substituent constant σ of -0.2 or less. When having a plurality of the electron-donating substituents, each of the electron-donating substituents may be the same or different. It may have a substituent selected from a hydrocarbon group having 1 to 20 carbon atoms, a silicon-containing group, a nitrogen-containing group, an oxygen-containing group, a halogen atom, and a halogen-containing group other than the electron-donating substituent. When having a plurality of the substituents, each of the substituents may be the same or different (hereinafter also referred to as "substituted aryl group containing an electron-donating group"). When ethylene, an α-olefin having 4 or more carbon atoms, and a non-conjugated polyene are copolymerized in the presence of an olefin polymerization catalyst containing the bridged metallocene compound, an advantage of further increasing the molecular weight of the produced ethylene·α-olefin·non-conjugated polyene copolymer (A) can be obtained.

[0099] An electron-donating group with a Hammett substituent constant σ of -0.2 or less is defined and exemplified as follows. The Hammett rule is an empirical rule proposed by L. P. Hammett in 1935 to quantitatively discuss the influence of substituents on the reactions or equilibria of benzene derivatives, and it is widely recognized as valid today. The substituent constants obtained by the Hammett rule include σp when substituted at the para-position of the benzene ring and σm when substituted at the meta-position, and these values can be found in many common literature. For example, the literature by Hansch and Taft [Chem. Rev., 91, 165 (1991)] describes in detail a very wide range of substituents. However, the σp and σm described in these literatures may have slightly different values depending on the literature even for the same substituent. In the present invention, in order to avoid the confusion caused by such a situation, for the substituents as far as described, the values described in Table 1 (pages 168 - 175) of the literature by Hansch and Taft [Chem. Rev., 91, 165 (1991)] are defined as the Hammett substituent constants σp and σm. In the present invention, an electron-donating group with a Hammett substituent constant σ of -0.2 or less means that when the electron-donating group is substituted at the para-position (4-position) of the phenyl group, it is an electron-donating group with σp of -0.2 or less, and when it is substituted at the meta-position (3-position) of the phenyl group, it is an electron-donating group with σm of -0.2 or less. Further, when the electron-donating group is substituted at the ortho-position (2-position) of the phenyl group, or when it is substituted at any position of an aryl group other than the phenyl group, it is an electron-donating group with σp of -0.2 or less.

[0100] Examples of electron-donating substituents having a Hammett substituent constant σp or σm of -0.2 or less include nitrogen-containing groups such as p-amino group (4-amino group), p-dimethylamino group (4-dimethylamino group), p-diethylamino group (4-diethylamino group), m-diethylamino group (3-diethylamino group); oxygen-containing groups such as p-methoxy group (4-methoxy group), p-ethoxy group (4-ethoxy group); tertiary hydrocarbon groups such as p-t-butyl group (4-t-butyl group); and silicon-containing groups such as p-trimethylsiloxy group (4-trimethylsiloxy group). It should be noted that the electron-donating substituents having a Hammett substituent constant σp or σm of -0.2 or less as defined in the present invention are not limited to the substituents described in Table 1 (pages 168 - 175) of the literature [Chem. Rev., 91, 165 (1991)] by Hansch and Taft. Even substituents not described in the literature, as long as the substituent constant σp or σm measured based on the Hammett rule falls within that range, are included in the electron-donating groups having a Hammett substituent constant σp or σm of -0.2 or less as defined in the present invention. Examples of such substituents include p-N-morpholinyl group (4-N-morpholinyl group), m-N-morpholinyl group (3-N-morpholinyl group).

[0101] In the substituted aryl group containing an electron-donating group, when a plurality of the electron-donating substituents are substituted, each of the electron-donating substituents may be the same or different. In addition to the electron-donating substituents, substituents selected from hydrocarbon groups having 1 to 20 carbon atoms, silicon-containing groups, nitrogen-containing groups, oxygen-containing groups, halogen atoms, and halogen-containing groups may be substituted. When a plurality of the substituents are substituted, each of the substituents may be the same or different. However, the sum of the substituent constants σ of the Hammett's rule of each of the electron-donating substituents and the substituents contained in one substituted aryl group is preferably -0.15 or less. Examples of such substituted aryl groups include m,p-dimethoxyphenyl group (3,4-dimethoxyphenyl group), p-(dimethylamino)-m-methoxyphenyl group (4-(dimethylamino)-3-methoxyphenyl group), p-(dimethylamino)-m-methylphenyl group (4-(dimethylamino)-3-methylphenyl group), p-methoxy-m-methylphenyl group (4-methoxy-3-methylphenyl group), p-methoxy-m,m-dimethylphenyl group (4-methoxy-3,5-dimethylphenyl group), and the like.

[0102] Examples of the hydrocarbon groups having 1 to 20 carbon atoms, silicon-containing groups, nitrogen-containing groups, oxygen-containing groups, halogen atoms, and halogen-containing groups that the substituted aryl group containing an electron-donating group may have include the specific examples of these atoms or substituents described above.

[0103] As a result of intensive studies on various bridged metallocene compounds (a), the applicant of the present application has found that in the bridged metallocene compound (a-3) represented by the above general formula [VII], when R 5 and R 6 are each a substituted aryl group containing an electron-donating group having one or more electron-donating substituents with a substituent constant σ of the Hammett's rule of -0.2 or less, when ethylene, an α-olefin having 4 or more carbon atoms, and a non-conjugated polyene are copolymerized in the presence of an olefin polymerization catalyst containing the bridged metallocene compound (a-3), the molecular weight of the resulting ethylene·α-olefin·non-conjugated polyene copolymer (A) becomes higher.

[0104] In the coordination polymerization of olefins using an organometallic complex catalyst such as the crosslinked metallocene compound (a-3), olefins repeatedly polymerize on the central metal of the catalyst, whereby the molecular chain of the olefin polymer containing the produced ethylene·α-olefin·non-conjugated polyene copolymer (A) grows (growth reaction), and it is known that the molecular weight of the olefin polymer increases. On the other hand, in a reaction called chain transfer, it is also known that when the molecular chain of the olefin polymer dissociates from the central metal of the catalyst, the growth reaction of the molecular chain stops, and thus the increase in the molecular weight of the olefin polymer also stops. From the above, the molecular weight of the olefin polymer is characterized by the ratio of the frequency of the growth reaction to the frequency of the chain transfer reaction, which is specific to the organometallic complex catalyst that produces it. That is, the larger the ratio of the frequency of the growth reaction to the frequency of the chain transfer reaction, the higher the molecular weight of the produced olefin polymer, and conversely, the smaller the ratio, the lower the molecular weight. Here, the frequency of each reaction can be estimated from the activation energy of each reaction, and it is considered that a reaction with a lower activation energy has a higher frequency, and conversely, a reaction with a higher activation energy has a lower frequency. Generally, it is known that the frequency of the growth reaction in olefin polymerization is sufficiently higher than the frequency of the chain transfer reaction, that is, the activation energy of the growth reaction is sufficiently lower than the activation energy of the chain transfer reaction. Therefore, the value obtained by subtracting the activation energy of the growth reaction from the activation energy of the chain transfer reaction (hereinafter, ΔE C ) is positive, and it is presumed that the larger this value is, the larger the frequency of the growth reaction is compared to the frequency of the chain transfer reaction, and as a result, the molecular weight of the produced olefin polymer becomes higher. The validity of the estimation of the molecular weight of the olefin polymer performed in this way is also supported by, for example, the calculation results of Laine et al. [Organometallics, 30, 1350 (2011)].

[0105] In the crosslinked metallocene compound (a-3) represented by the above general formula [VII], when R 5 and R 6 are particularly electron-donating group-containing substituted aryl groups substituted with one or more electron-donating substituents having a Hammett substituent constant σ of -0.2 or less, the above ΔEC increases, and when ethylene, an α-olefin having 4 or more carbon atoms, and a non-conjugated polyene are copolymerized in the presence of an olefin polymerization catalyst containing the crosslinked metallocene compound (a-3), it is presumed that the molecular weight of the produced ethylene·α-olefin·non-conjugated polyene copolymer (A) becomes high.

[0106] In the crosslinked metallocene compound (a-3) represented by the above general formula [VII], R 5 and R 6 The electron-donating substituents contained in are more preferably groups selected from nitrogen-containing groups and oxygen-containing groups.

[0107] In the crosslinked metallocene compound (a-3) represented by the above general formula [VII], R 5 and R 6 are more preferably substituted phenyl groups containing groups selected from nitrogen-containing groups and oxygen-containing groups as the above electron-donating substituents. For example, when synthesized according to the method as in the above formula [VIII], various benzophenones as raw materials are commercially available from general reagent manufacturers, so the raw materials are easily available, the manufacturing process is simplified, the manufacturing cost is further reduced, and ultimately, the manufacturing cost of the ethylene·α-olefin·non-conjugated polyene copolymer (A) can be reduced by using this crosslinked metallocene compound.

[0108] Here, examples of the substituted phenyl group containing a group selected from a nitrogen-containing group and an oxygen-containing group as the electron-donating substituent include an o-aminophenyl group (2-aminophenyl group), a p-aminophenyl group (4-aminophenyl group), an o-(dimethylamino)phenyl group (2-(dimethylamino)phenyl group), a p-(dimethylamino)phenyl group (4-(dimethylamino)phenyl group), an o-(diethylamino)phenyl group (2-(diethylamino)phenyl group), a p-(diethylamino)phenyl group (4-(diethylamino)phenyl group), an m-(diethylamino)phenyl group (3-(diethylamino)phenyl group), an o-methoxyphenyl group (2-methoxyphenyl group), a p-methoxyphenyl group (4-methoxyphenyl group), an o-ethoxyphenyl group (2-ethoxyphenyl group), a p-ethoxyphenyl group (4-ethoxyphenyl group), an o-N-morpholinylphenyl group (2-N-morpholinylphenyl group), a p-N-morpholinylphenyl group (4-N-morpholinylphenyl group), an m-N-morpholinylphenyl group (3-N-morpholinylphenyl group), an o,p-dimethoxyphenyl group (2,4-dimethoxyphenyl group), an m,p-dimethoxyphenyl group (3,4-dimethoxyphenyl group), a p-(dimethylamino)-m-methoxyphenyl group (4-(dimethylamino)-3-methoxyphenyl group), a p-(dimethylamino)-m-methylphenyl group (4-(dimethylamino)-3-methylphenyl group), a p-methoxy-m-methylphenyl group (4-methoxy-3-methylphenyl group), a p-methoxy-m,m-dimethylphenyl group (4-methoxy-3,5-dimethylphenyl group), and the like.

[0109] In the crosslinked metallocene compound (a-3) represented by the above general formula [VII], R 5 and R 6It is more preferable that it is a substituted phenyl group containing a group selected from a nitrogen-containing group and an oxygen-containing group as the above electron-donating substituent at the meta-position and / or para-position with respect to the bond to the carbon atom as the above Y. For example, when synthesizing according to a method such as the above formula [VIII], the synthesis becomes easier compared to the case where the group is substituted at the ortho-position, the manufacturing process is simplified, the manufacturing cost is further reduced, and ultimately, by using this bridged metallocene compound, the manufacturing cost of the ethylene-based copolymer can be reduced.

[0110] In the bridged metallocene compound (a-3) represented by the above general formula [VII], R 5 and R 6 When they are substituted phenyl groups containing a nitrogen-containing group as the above electron-donating substituent at the meta-position and / or para-position with respect to the bond to the carbon atom as the above Y, it is more preferable that the nitrogen-containing group is a group represented by the following general formula [II].

[0111]

Chemical formula

[0112] (In formula [II], R 7 and R 8 are atoms or substituents selected from a hydrogen atom, a hydrocarbon group having 1 to 20 carbon atoms, a silicon-containing group, an oxygen-containing group, and a halogen-containing group, and may be the same or different from each other, and may be bonded to each other to form a ring. The line drawn to the right of N represents the bond to the phenyl group.)

[0113] R 7 and R 8 As the hydrocarbon group having 1 to 20 carbon atoms, the silicon-containing group, the oxygen-containing group, and the halogen-containing group as, specific examples of these substituents described above can be given. Such a bridged metallocene compound (a-4) is represented by the following general formula [IX].

[0114]

Chemical formula

[0115] (In formula [IX], the definitions of M, Q, j, etc. are as described above. R 7 , R 8 and R 10 are substituents selected from a hydrogen atom, a hydrocarbon group having 1 to 20 carbon atoms, a silicon-containing group, a nitrogen-containing group, an oxygen-containing group, a halogen atom, and a halogen-containing group, and may be the same or different from each other. Among R 7 , R 8 and R 10 , adjacent substituents may be bonded to each other to form a ring. NR 7 R 8 is a nitrogen-containing group with a Hammett substituent constant σ of -0.2 or less. When there are a plurality of such nitrogen-containing groups, the nitrogen-containing groups may be the same or different from each other. n is an integer from 1 to 3, and m is an integer from 0 to 4.)

[0116] In the crosslinked metallocene compound (a-3) represented by the above general formula [VII], when R 5 and R 6 are substituted phenyl groups containing an oxygen-containing group as the above electron-donating substituent at the meta-position and / or para-position with respect to the bond to the carbon atom as Y above, it is more preferable that the oxygen-containing group is a group represented by the following general formula [III].

[0117] [Chemical formula]

[0118] (In formula [III], R 9 is an atom or substituent selected from a hydrogen atom, a hydrocarbon group having 1 to 20 carbon atoms, a silicon-containing group, a nitrogen-containing group, and a halogen-containing group. The line drawn to the right of O represents the bond to the phenyl group.)

[0119] R 9Examples of the hydrocarbon group, silicon-containing group, nitrogen-containing group, and halogen-containing group having 1 to 20 carbon atoms as described above include specific examples of these substituents mentioned above. Such a crosslinked metallocene compound (a-5) is represented by the following general formula [X].

[0120]

Chemical formula

[0121] (In formula [X], the definitions of M, Q, j, etc. are as described above. R 9 and R 10 are atoms or substituents selected from a hydrogen atom, a hydrocarbon group having 1 to 20 carbon atoms, a silicon-containing group, a nitrogen-containing group, an oxygen-containing group, a halogen atom, and a halogen-containing group, and may be the same or different from each other. Adjacent substituents of R 10 may be bonded to each other to form a ring. OR 9 is an oxygen-containing group with a Hammett substituent constant σ of -0.2 or less. When there are a plurality of such oxygen-containing groups, each oxygen-containing group may be the same or different from each other. n is an integer of 1 to 3, and m is an integer of 0 to 4.)

[0122] In the crosslinked metallocene compound (a) represented by the above general formula [I], the crosslinked metallocene compound (a-1) represented by the above general formula [V], the crosslinked metallocene compound (a-2) represented by the above general formula [VI], the crosslinked metallocene compound (a-3) represented by the above general formula [VII], the crosslinked metallocene compound (a-4) represented by the above general formula [IX], or the crosslinked metallocene compound (a-5) represented by the above general formula [X], it is more preferable that M is a hafnium atom. When ethylene, an α-olefin having 4 or more carbon atoms, and a non-conjugated polyene are copolymerized in the presence of an olefin polymerization catalyst containing the above crosslinked metallocene compound in which M is a hafnium atom, advantages such as further increasing the molecular weight of the resulting ethylene·α-olefin·non-conjugated polyene copolymer (A) and improving the copolymerization performance of the non-conjugated polyene can be obtained.

[0123] (Exemplification of the bridged metallocene compound (a), etc.) Examples of such bridged metallocene compounds (a) include [Dimethylmethylene(η 5 -cyclopentadienyl)(η 5 -2,3,6,7-tetramethylfluorenyl)]hafnium dichloride, [Diethylmethylene(η 5 -cyclopentadienyl)(η 5 -2,3,6,7-tetramethylfluorenyl)]hafnium dichloride, [Di-n-butylmethylene(η 5 -cyclopentadienyl)(η 5 -2,3,6,7-tetramethylfluorenyl)]hafnium dichloride, [Dicyclopentylmethylene(η 5 -cyclopentadienyl)(η 5 -2,3,6,7-tetramethylfluorenyl)]hafnium dichloride, [Dicyclohexylmethylene(η 5 -cyclopentadienyl)(η 5 -2,3,6,7-tetramethylfluorenyl)]hafnium dichloride, [Cyclopentylidene(η 5 -cyclopentadienyl)(η 5 -2,3,6,7-tetramethylfluorenyl)]hafnium dichloride, [Cyclohexylidene(η 5 -cyclopentadienyl)(η 5 -2,3,6,7-tetramethylfluorenyl)]hafnium dichloride, [Diphenylmethylene(η 5 -cyclopentadienyl)(η 5 -2,3,6,7-tetramethylfluorenyl)]hafnium dichloride, [Di-1-naphthylmethylene(η 5 -cyclopentadienyl)(η 5 -2,3,6,7-tetramethylfluorenyl)]hafnium dichloride, [Di-2-naphthylmethylene(η 5 -cyclopentadienyl)(η 5 -2,3,6,7-tetramethylfluorenyl)]hafnium dichloride, [Bis(3-methylphenyl)methylene(η5 -(Cyclopentadienyl)(η 5 -2,3,6,7-Tetramethylfluorenyl)]hafnium dichloride, [Bis(4-methylphenyl)methylene(η 5 -Cyclopentadienyl)(η 5 -2,3,6,7-Tetramethylfluorenyl)]hafnium dichloride, [Bis(3,4-dimethylphenyl)methylene(η 5 -Cyclopentadienyl)(η 5 -2,3,6,7-Tetramethylfluorenyl)]hafnium dichloride, [Bis(4-n-hexylphenyl)methylene(η 5 -Cyclopentadienyl)(η 5 -2,3,6,7-Tetramethylfluorenyl)]hafnium dichloride, [Bis(4-cyclohexylphenyl)methylene(η 5 -Cyclopentadienyl)(η 5 -2,3,6,7-Tetramethylfluorenyl)]hafnium dichloride, [Bis(4-t-butylphenyl)methylene(η 5 -Cyclopentadienyl)(η 5 -2,3,6,7-Tetramethylfluorenyl)]hafnium dichloride, [Bis(3-methoxyphenyl)methylene(η 5 -Cyclopentadienyl)(η 5 -2,3,6,7-Tetramethylfluorenyl)]hafnium dichloride, [Bis(4-methoxyphenyl)methylene(η 5 -Cyclopentadienyl)(η 5 -2,3,6,7-Tetramethylfluorenyl)]hafnium dichloride, [Bis(3,4-dimethoxyphenyl)methylene(η 5 -Cyclopentadienyl)(η 5 -2,3,6,7-Tetramethylfluorenyl)]hafnium dichloride, [Bis(4-methoxy-3-methylphenyl)methylene(η 5 -Cyclopentadienyl)(η 5 -2,3,6,7-Tetramethylfluorenyl)]hafnium dichloride, [Bis(4-methoxy-3,4-dimethylphenyl)methylene(η 5-(Cyclopentadienyl)(η 5 -2,3,6,7-Tetramethylfluorenyl)]hafnium dichloride, [Bis(4-ethoxyphenyl)methylene(η 5 -Cyclopentadienyl)(η 5 -2,3,6,7-Tetramethylfluorenyl)]hafnium dichloride, [Bis(4-phenoxyphenyl)methylene(η 5 -Cyclopentadienyl)(η 5 -2,3,6,7-Tetramethylfluorenyl)]hafnium dichloride, [Bis{4-(trimethylsiloxy)phenyl}methylene(η 5 -Cyclopentadienyl)(η 5 -2,3,6,7-Tetramethylfluorenyl)]hafnium dichloride, [Bis{3-(dimethylamino)phenyl}methylene(η 5 -Cyclopentadienyl)(η 5 -2,3,6,7-Tetramethylfluorenyl)]hafnium dichloride, [Bis{4-(dimethylamino)phenyl}methylene(η 5 -Cyclopentadienyl)(η 5 -2,3,6,7-Tetramethylfluorenyl)]hafnium dichloride, [Bis(4-N-morpholinylphenyl)(η 5 -Cyclopentadienyl)(η 5 -2,3,6,7-Tetramethylfluorenyl)]hafnium dichloride, [Bis{4-(trimethylsilyl)phenyl}methylene(η 5 -Cyclopentadienyl)(η 5 -2,3,6,7-Tetramethylfluorenyl)]hafnium dichloride, [Bis(3-chlorophenyl)methylene(η 5 -Cyclopentadienyl)(η 5 -2,3,6,7-Tetramethylfluorenyl)]hafnium dichloride, [Bis(4-chlorophenyl)methylene(η 5 -Cyclopentadienyl)(η 5 -2,3,6,7-Tetramethylfluorenyl)]hafnium dichloride, [Bis(3-fluorophenyl)methylene(η5 -(Cyclopentadienyl)(η 5 -2,3,6,7-Tetramethylfluorenyl)]hafnium dichloride, [Bis(4-fluorophenyl)methylene(η 5 -Cyclopentadienyl)(η 5 -2,3,6,7-Tetramethylfluorenyl)]hafnium dichloride, [Bis{3-(trifluoromethyl)phenyl}methylene(η 5 -Cyclopentadienyl)(η 5 -2,3,6,7-Tetramethylfluorenyl)]hafnium dichloride, [Bis{4-(trifluoromethyl)phenyl}methylene(η 5 -Cyclopentadienyl)(η 5 -2,3,6,7-Tetramethylfluorenyl)]hafnium dichloride, [Methylphenylmethylene(η 5 -Cyclopentadienyl)(η 5 -2,3,6,7-Tetramethylfluorenyl)]hafnium dichloride, [Methyl(4-methylphenyl)methylene(η 5 -Cyclopentadienyl)(η 5 -2,3,6,7-Tetramethylfluorenyl)]hafnium dichloride, [Methyl(4-methoxyphenyl)methylene(η 5 -Cyclopentadienyl)(η 5 -2,3,6,7-Tetramethylfluorenyl)]hafnium dichloride, [Methyl{4-(dimethylamino)phenyl}methylene(η 5 -Cyclopentadienyl)(η 5 -2,3,6,7-Tetramethylfluorenyl)]hafnium dichloride, [Methyl(4-N-morpholinylphenyl)methylene(η 5 -Cyclopentadienyl)(η 5 -2,3,6,7-Tetramethylfluorenyl)]hafnium dichloride, [Dimethylsilylene(η 5 -Cyclopentadienyl)(η 5 -2,3,6,7-Tetramethylfluorenyl)]hafnium dichloride, [Diethylsilylene(η 5 -Cyclopentadienyl)(η5 -2,3,6,7-Tetramethylfluorenyl)]hafnium dichloride, [dicyclohexylsilylene(η 5 -cyclopentadienyl)(η 5 -2,3,6,7-Tetramethylfluorenyl)]hafnium dichloride, [diphenylsilylene(η 5 -cyclopentadienyl)(η 5 -2,3,6,7-Tetramethylfluorenyl)]hafnium dichloride, [di(4-methylphenyl)silylene(η 5 -cyclopentadienyl)(η 5 -2,3,6,7-Tetramethylfluorenyl)]hafnium dichloride, [Dimethylgermylene(η 5 -cyclopentadienyl)(η 5 -2,3,6,7-Tetramethylfluorenyl)]hafnium dichloride, [diphenylgermylene(η 5 -cyclopentadienyl)(η 5 -2,3,6,7-Tetramethylfluorenyl)]hafnium dichloride, [1-(η 5 -cyclopentadienyl)-2-(η 5 -2,3,6,7-Tetramethylfluorenyl)ethylene]hafnium dichloride, [1-(η 5 -cyclopentadienyl)-3-(η 5 -2,3,6,7-Tetramethylfluorenyl)propylene]hafnium dichloride, [1-(η 5 -cyclopentadienyl)-2-(η 5 -2,3,6,7-Tetramethylfluorenyl)-1,1,2,2-tetramethylsilylene]hafnium dichloride, [1-(η 5 -cyclopentadienyl)-2-(η 5 -2,3,6,7-Tetramethylfluorenyl)phenylene]hafnium dichloride, and compounds in which the hafnium atom of these compounds is replaced with a zirconium atom or compounds in which the chloro ligand is replaced with a methyl group, etc. are exemplified, but the bridged metallocene compound (a) is not limited to these examples.

[0124] <Method for Producing Bridged Metallocene Compound> The above bridged metallocene compound can be produced by a known method, and the production method is not particularly limited. As the production method, for example, J. Organomet. Chem., 63, 509 (1996), WO2006 / 123759, a publication related to an application by the present applicant, WO01 / 27124, JP-A-2004-168744, JP-A-2004-175759, JP-A-2000-212194, etc. can be used for production.

[0125] <Preferred Form When Using Bridged Metallocene Compound as Catalyst for Ethylene·α-Olefin·Non-Conjugated Polyene Copolymer (A)> Next, the preferred form when using the above bridged metallocene compound as a catalyst for ethylene·α-olefin·non-conjugated polyene copolymer (A) (olefin polymerization catalyst) will be described.

[0126] When using the bridged metallocene compound as an olefin polymerization catalyst component, the catalyst is (a) the bridged metallocene compound represented by the general formula [I], and (b) at least one compound selected from (b-1) an organometallic compound, (b-2) an organoaluminum oxy compound, and (b-3) a compound that reacts with the bridged metallocene compound (a) to form an ion pair, and furthermore, if necessary, (c) a particulate carrier.

[0127] Hereinafter, each component will be specifically described. <(b-1) Organometallic Compound> As the (b-1) organometallic compound used in the present invention, specifically, organometallic compounds of Groups 1, 2, 12, and 13 of the periodic table such as the following general formulas [VII] to [IX] are used.

[0128] (b-1a) General formula R a m Al(OR b ) nH p X q ···[VII]

[0129] (In formula [VII], R a and R b may be the same as or different from each other, and each represents a hydrocarbon group having 1 to 15 carbon atoms, preferably 1 to 4 carbon atoms; X represents a halogen atom; m is a number such that 0 < m ≦ 3, n is a number such that 0 ≦ n < 3, p is a number such that 0 ≦ p < 3, q is a number such that 0 ≦ q < 3, and m + n + p + q = 3.) An organoaluminum compound represented by the formula.

[0130] Examples of such compounds include trialkylaluminums such as trimethylaluminum, triethylaluminum, triisobutylaluminum, tri-n-octylaluminum, tricycloalkylaluminum, isobutylaluminum dichloride, diethylaluminum chloride, ethylaluminum dichloride, ethylaluminum sesquichloride, methylaluminum dichloride, dimethylaluminum chloride, and diisobutylaluminum hydride.

[0131] (b-1b) General formula M 2 AlR a 4···[VIII]

[0132] (In formula [VIII], M 2 represents Li, Na or K, and R a is a hydrocarbon group having 1 to 15 carbon atoms, preferably 1 to 4 carbon atoms.) A complex alkyl compound of a Group 1 metal of the periodic table and aluminum represented by the formula.

[0133] Examples of such compounds include LiAl(C2H5)4, LiAl(C7H 15 )4, etc.

[0134] (b-1c) General formula R a R b M 3 ···[IX]

[0135] (In formula [IX], R aand R b may be the same as or different from each other and each represents a hydrocarbon group having 1 to 15 carbon atoms, preferably 1 to 4 carbon atoms, and M 3 is Mg, Zn or Cd. A dialkyl compound having a Group 2 or Group 12 metal of the periodic table represented by ().

[0136] Among the above organometallic compounds (b-1), organoaluminum compounds such as triethylaluminum, triisobutylaluminum, and tri-n-octylaluminum are preferable. Further, such an organometallic compound (b-1) may be used alone or in combination of two or more.

[0137] 〈(b-2) Organoaluminum oxy compound〉 The (b-2) organoaluminum oxy compound used in the present invention may be a conventionally known aluminoxane or a benzene-insoluble organoaluminum oxy compound as exemplified in JP-A-2-78687.

[0138] Conventionally known aluminoxanes can be produced, for example, by the following methods and are usually obtained as a solution in a hydrocarbon solvent. (1) A method in which an organoaluminum compound such as trialkylaluminum is added to a hydrocarbon medium suspension of a compound containing adsorbed water or a salt containing water of crystallization, such as magnesium chloride hydrate, copper sulfate hydrate, aluminum sulfate hydrate, nickel sulfate hydrate, cerium(I) chloride hydrate, etc., to react the adsorbed water or water of crystallization with the organoaluminum compound. (2) A method in which water, ice or steam is directly allowed to act on an organoaluminum compound such as trialkylaluminum in a medium such as benzene, toluene, ethyl ether, tetrahydrofuran, etc. (3) A method in which an organotin oxide such as dimethyltin oxide or dibutyltin oxide is reacted with an organoaluminum compound such as trialkylaluminum in a medium such as decane, benzene, toluene, etc.

[0139] The aluminoxane may contain a small amount of an organometallic component. Further, after distilling and removing the solvent or unreacted organoaluminum compound from the recovered aluminoxane solution, it may be redissolved in a solvent or suspended in a poor solvent for aluminoxane.

[0140] Specific examples of the organoaluminum compound used in preparing the aluminoxane include the same organoaluminum compounds as those exemplified as the organoaluminum compounds belonging to the above (b-1a).

[0141] Among these, trialkylaluminum and tricycloalkylaluminum are preferable, and among them, trimethylaluminum and triisobutylaluminum are particularly preferable. The above organoaluminum compounds are used alone or in combination of two or more.

[0142] Further, the benzene-insoluble organoaluminum oxy compound, which is one embodiment of the (b-2) organoaluminum oxy compound used in the present invention, has an Al component dissolved in benzene at 60 °C of usually 10% by weight or less, preferably 5% by weight or less, particularly preferably 2% by weight or less in terms of Al atoms based on 100% by weight of benzene, that is, those insoluble or hardly soluble in benzene are preferable.

[0143] Examples of the (b-2) organoaluminum oxy compound used in the present invention also include an organoaluminum oxy compound containing boron represented by the following general formula [X].

[0144]

Chemical formula

[0145] (In formula [X], R 1 represents a hydrocarbon group having 1 to 10 carbon atoms, and R 2 ~R 5may be the same as or different from each other, and represent a hydrogen atom, a halogen atom, or a hydrocarbon group having 1 to 10 carbon atoms.)

[0146] The organoaluminum oxy compound containing boron represented by the general formula [X] is obtained by reacting an alkylboronic acid represented by the following general formula [XI] with R 1 -B(OH)2…[XI] (In the formula [XI], R 1 represents the same group as R 1 in the general formula [X].) an organoaluminum compound in an inert gas atmosphere in an inert solvent at a temperature of -80°C to room temperature for 1 minute to 24 hours.)

[0147] Specific examples of the alkylboronic acid represented by the general formula [XI] include methylboronic acid, ethylboronic acid, isopropylboronic acid, n-propylboronic acid, n-butylboronic acid, isobutylboronic acid, n-hexylboronic acid, cyclohexylboronic acid, phenylboronic acid, 3,5-difluorophenylboronic acid, pentafluorophenylboronic acid, 3,5-bis(trifluoromethyl)phenylboronic acid, and the like.)

[0148] Among these, methylboronic acid, n-butylboronic acid, isobutylboronic acid, 3,5-difluorophenylboronic acid, and pentafluorophenylboronic acid are preferred. These may be used alone or in combination of two or more.)

[0149] Specific examples of the organoaluminum compound to be reacted with such an alkylboronic acid include the same organoaluminum compounds as those exemplified as the organoaluminum compounds belonging to (b-1a).

[0150] Among these, trialkylaluminum and tricycloalkylaluminum are preferred, and trimethylaluminum, triethylaluminum, and triisobutylaluminum are particularly preferred. These may be used alone or in combination of two or more. The above-mentioned (b-2) organoaluminumoxy compound may be used alone or in combination of two or more.

[0151] 〈(b-3) Compound that reacts with the transition metal compound (a) to form an ion pair〉 Examples of the compound (b-3) (hereinafter referred to as "ionizing ionic compound") that reacts with the above-mentioned bridged metallocene compound (a) to form an ion pair include Lewis acids, ionic compounds, borane compounds, and carborane compounds described in JP-T-1-501950, JP-T-1-502036, JP-A-3-179005, JP-A-3-179006, JP-A-3-207703, JP-A-3-207704, USP-5321106, etc. Further, heteropoly compounds and isopoly compounds can also be mentioned. Such ionizing ionic compounds (b-3) may be used alone or in combination of two or more.

[0152] Specifically, examples of the Lewis acid include compounds represented by BR3 (R is a phenyl group or fluorine which may have a substituent such as fluorine, a methyl group, or a trifluoromethyl group), for example, trifluoroboron, triphenylboron, tris(4-fluorophenyl)boron, tris(3,5-difluorophenyl)boron, tris(4-fluoromethylphenyl)boron, tris(pentafluorophenyl)boron, tris(p-tolyl)boron, tris(o-tolyl)boron, tris(3,5-dimethylphenyl)boron, etc.

[0153] Examples of the ionic compound include compounds represented by the following general formula [XII].

[0154]

Chemical formula

[0155] (In formula [XII], R 1+ is, for example, H + , a carbonium cation, an oxonium cation, an ammonium cation, a phosphonium cation, a cycloheptyltrienyl cation, a ferrocenium cation having a transition metal, and the like. R 2 ~R 5 may be the same as or different from each other, and is an organic group, preferably an aryl group or a substituted aryl group.)

[0156] Specific examples of the carbonium cation include trisubstituted carbonium cations such as triphenylcarbonium cation, tri(methylphenyl)carbonium cation, and tri(dimethylphenyl)carbonium cation, and the like.

[0157] Specific examples of the ammonium cation include trialkylammonium cations such as trimethylammonium cation, triethylammonium cation, tripropylammonium cation, tributylammonium cation, and tri(n-butyl)ammonium cation; N,N-dialkylanilinium cations such as N,N-dimethylanilinium cation, N,N-diethylanilinium cation, and N,N,2,4,6-pentamethylanilinium cation; dialkylammonium cations such as di(isopropyl)ammonium cation and dicyclohexylammonium cation, and the like.

[0158] Specific examples of the phosphonium cation include triarylphosphonium cations such as triphenylphosphonium cation, tri(methylphenyl)phosphonium cation, and tri(dimethylphenyl)phosphonium cation, and the like.

[0159] R 1+Examples include carbonium cations and ammonium cations, and particularly preferred are triphenylcarbonium cations, N,N-dimethylanilinium cations, and N,N-diethylanilinium cations.

[0160] Examples of the ionic compound also include trialkyl-substituted ammonium salts, N,N-dialkylanilinium salts, dialkylammonium salts, and triarylphosphonium salts.

[0161] Specific examples of the trialkyl-substituted ammonium salt include triethylammonium tetra(phenyl)borate, tripropylammonium tetra(phenyl)borate, tri(n-butyl)ammonium tetra(phenyl)borate, trimethylammonium tetra(p-tolyl)borate, trimethylammonium tetra(o-tolyl)borate, tri(n-butyl)ammonium tetra(pentafluorophenyl)borate, tripropylammonium tetra(o,p-dimethylphenyl)borate, tri(n-butyl)ammonium tetra(N,N-dimethylphenyl)borate, tri(n-butyl)ammonium tetra(p-trifluoromethylphenyl)borate, tri(n-butyl)ammonium tetra(3,5-ditrifluoromethylphenyl)borate, and tri(n-butyl)ammonium tetra(o-tolyl)borate.

[0162] Specific examples of the N,N-dialkylanilinium salt include N,N-dimethylanilinium tetra(phenyl)borate, N,N-diethylanilinium tetra(phenyl)borate, and N,N,2,4,6-pentamethylanilinium tetra(phenyl)borate.

[0163] Specific examples of the dialkylammonium salt include di(1-propyl)ammonium tetra(pentafluorophenyl)borate and dicyclohexylammonium tetra(phenyl)borate.

[0164] Furthermore, examples of the ionic compound include triphenylcarbenium tetrakis(pentafluorophenyl)borate, N,N-dimethylanilinium tetrakis(pentafluorophenyl)borate, ferrocenium tetra(pentafluorophenyl)borate, triphenylcarbenium pentaphenylcyclopentadienyl complex, N,N-diethylanilinium pentaphenylcyclopentadienyl complex, and boron compounds represented by the following formula [XIII] or [XIV].

[0165]

Chem.

[0166]

Chem.

[0167] Specific examples of the borane compound include, for example decaborane; salts of anions such as bis[tri(n-butyl)ammonium] nonaborate, bis[tri(n-butyl)ammonium] decaborate, bis[tri(n-butyl)ammonium] undecaborate, bis[tri(n-butyl)ammonium] dodecaborate, bis[tri(n-butyl)ammonium] decachlorodecaborate, and bis[tri(n-butyl)ammonium] dodecachlorododecaborate; salts of metal borane anions such as tri(n-butyl)ammonium bis(dodecahydridedodecaborate) cobaltate(III) and bis[tri(n-butyl)ammonium] bis(dodecahydridedodecaborate) nickelate(III).

[0168] Specific examples of the carborane compound include, for example, 4-carbanonaborane, 1,3-dicarbanonaborane, 6,9-dicarbadecaborane, dodecahydride-1-phenyl-1,3-dicarbanonaborane, dodecahydride-1-methyl-1,3-dicarbanonaborane, undecahydride-1,3-dimethyl-1,3-dicarbanonaborane, 7,8-dicarboundecaborane, 2,7-dicarboundecaborane, undecahydride-7,8-dimethyl-7,8-dicarboundecaborane, dodecahydride-11-methyl-2,7-dicarboundecaborane, tri(n-butyl)ammonium 1-carbadodecaborate, tri(n-butyl)ammonium-1-carbaundecaborate, tri(n-butyl)ammonium-1-carbadodecaborate, tri(n-butyl)ammonium-1-trimethylsilyl-1-carbadodecaborate, tri(n-butyl)ammonium bromo-1-carbadodecaborate, tri(n-butyl)ammonium-6-carbadodecaborate, tri(n-butyl)ammonium-7-carbaundecaborate, tri(n-butyl)ammonium-7,8-dicarboundecaborate, tri(n-butyl)ammonium-2,9-dicarboundecaborate, tri(n-butyl)ammonium dodecahydride-8-methyl-7,9-dicarboundecaborate, tri(n-butyl)ammonium undecahydride-8-ethyl-7,9-dicarboundecaborate, tri(n-butyl)ammonium undecahydride-8-butyl-7,9-dicarboundecaborate, tri(n-butyl)ammonium undecahydride-8-allyl-7,9-dicarboundecaborate, tri(n-butyl)ammonium undecahydride-9-trimethylsilyl-7,8-dicarboundecaborate, tri(n-butyl)ammonium undecahydride-4,6-dibromo-7-carbaundecaborate, and salts of anions such as these; Salts of metal carborane anions such as tris(n-butyl)ammonium bis(nonahydride-1,3-dicarbanonaborate)cobaltate(III), tris(n-butyl)ammonium bis(undecahydride-7,8-dicarbaundecaborate)ferrate(III), tris(n-butyl)ammonium bis(undecahydride-7,8-dicarbaundecaborate)cobaltate(III), tris(n-butyl)ammonium bis(undecahydride-7,8-dicarbaundecaborate)nickelate(III), tris(n-butyl)ammonium bis(undecahydride-7,8-dicarbaundecaborate)cuprate(III), tris(n-butyl)ammonium bis(undecahydride-7,8-dicarbaundecaborate)aurate(III), tris(n-butyl)ammonium bis(nonahydride-7,8-dimethyl-7,8-dicarbaundecaborate)ferrate(III), tris(n-butyl)ammonium bis(nonahydride-7,8-dimethyl-7,8-dicarbaundecaborate)chromate(III), tris(n-butyl)ammonium bis(tribromooctahydride-7,8-dicarbaundecaborate)cobaltate(III), tris[tris(n-butyl)ammonium] bis(undecahydride-7-carbaundecaborate)chromate(III), bis[tris(n-butyl)ammonium] bis(undecahydride-7-carbaundecaborate)manganate(IV), bis[tris(n-butyl)ammonium] bis(undecahydride-7-carbaundecaborate)cobaltate(III), bis[tris(n-butyl)ammonium] bis(undecahydride-7-carbaundecaborate)nickelate(IV), etc.

[0169] The heteropoly compound is composed of an atom selected from silicon, phosphorus, titanium, germanium, arsenic and tin, and one or more atoms selected from vanadium, niobium, molybdenum and tungsten. Specifically, phosphovanadic acid, germanovanadic acid, arsenic vanadic acid, phosphoniobic acid, germanoniobic acid, silicomolybdic acid, phosphomolybdic acid, titanium molybdic acid, germanomolybdic acid, arsenic molybdic acid, tin molybdic acid, phosphotungstic acid, germanotungstic acid, tin tungstic acid, phosphomolybdovanadic acid, phosphotungstovanadic acid, germanotungstovanadic acid, phosphomolybdotungstovanadic acid, germanomolybdotungstovanadic acid, phosphomolybdotungstic acid, phosphomolybdoniobic acid, and salts of these acids, for example, salts with metals of Group 1 or 2 of the periodic table, specifically, lithium, sodium, potassium, rubidium, cesium, beryllium, magnesium, calcium, strontium, barium, etc., and organic salts such as triphenylethyl salts can be used, but it is not limited to this.

[0170] (b-3) Among the ionized ionic compounds, the above-mentioned ionic compounds are preferred, and among them, triphenylcarbenium tetrakis(pentafluorophenyl)borate and N,N-dimethylanilinium tetrakis(pentafluorophenyl)borate are more preferred. (b-3) The ionized ionic compound is used alone or in combination of two or more.

[0171] When the transition metal compound (a) represented by the above general formula [I] is used as a catalyst, an organometallic compound (b-1) such as triisobutylaluminum, an organoaluminum oxy compound (b-2) such as methylaluminoxane, or an ionized ionic compound (b-3) such as triphenylcarbenium tetrakis(pentafluorophenyl)borate is used in combination, it shows very high polymerization activity in the production of ethylene·α-olefin·non-conjugated polyene copolymer.

[0172] In addition, the olefin polymerization catalyst can optionally use a carrier (c) together with the transition metal compound (a) and at least one compound (b) selected from (b-1) an organometallic compound, (b-2) an organoaluminum oxy compound, and (b-3) an ionized ionic compound.

[0173] 〈(c) Carrier〉 In the present invention, the carrier (c) used as needed is an inorganic compound or an organic compound and is a granular or particulate solid.

[0174] Among these, as the inorganic compound, a porous oxide, an inorganic halide, clay, a clay mineral, or an ion-exchangeable layered compound is preferable. As the porous oxide, specifically, SiO2, Al2O3, MgO, ZrO, TiO2, B2O3, CaO, ZnO, BaO, ThO2, etc., or a composite or mixture containing these can be used. For example, natural or synthetic zeolite, SiO2-MgO, SiO2-Al2O3, SiO2-TiO2, SiO2-V2O5, SiO2-Cr2O3, SiO2-TiO2-MgO, etc. can be used. Among these, those mainly composed of SiO2 and / or Al2O3 are preferable. Such porous oxides have different properties depending on the type and production method, but the carrier preferably used in the present invention has a particle size of 10 to 300 μm, preferably 20 to 200 μm, and a specific surface area of 50 to 1000 m 2 / g, preferably 100 to 700 m 2 / g, and a pore volume in the range of 0.3 to 3.0 cm 3 / g is desirable. Such a carrier is calcined at 100 to 1000 °C, preferably 150 to 700 °C, as needed before use.

[0175] As the inorganic halide, MgCl2, MgBr2, MnCl2, MnBr2, etc. are used. The inorganic halide may be used as it is, or may be used after being pulverized by a ball mill or a vibration mill. Also, after dissolving the inorganic halide in a solvent such as alcohol, a precipitate obtained by precipitating it into fine particles with a precipitating agent can be used. Clay is usually composed mainly of clay minerals. An ion-exchangeable layered compound is a compound having a crystal structure in which planes formed by ionic bonds or the like are stacked parallel to each other with a weak binding force, and the contained ions are exchangeable. Most clay minerals are ion-exchangeable layered compounds. Further, as these clays, clay minerals, and ion-exchangeable layered compounds, not only naturally occurring ones but also synthetic ones can be used.

[0176] In addition, examples of the clay, clay mineral, or ion-exchangeable layered compound include clay, clay mineral, and ion-crystalline compounds having a layered crystal structure such as hexagonal close-packing type, antimony type, CdCl2 type, CdI2 type, etc. Examples of such clays and clay minerals include kaolin, bentonite, kibushi clay, gyrolite clay, allophane, hisingerite, pyrophyllite, ummo group, montmorillonite group, vermiculite, ryokudite group, palygorskite, kaolinite, nacrite, dickite, halloysite, etc. Examples of the ion-exchangeable layered compound include crystalline acidic salts of polyvalent metals such as α-Zr(HAsO4)2·H2O, α-Zr(HPO4)2, α-Zr(KPO4)2·3H2O, α-Ti(HPO4)2, α-Ti(HAsO4)2·H2O, α-Sn(HPO4)2·H2O, γ-Zr(HPO4)2, γ-Ti(HPO4)2, γ-Ti(NH4PO4)2·H2O, etc.

[0177] Such a clay, clay mineral, or ion-exchangeable layered compound preferably has a pore volume of 0.1 cc / g or more with a pore radius of 20 Å or more measured by the mercury intrusion method, and particularly preferably 0.3 to 5 cc / g. Here, the pore volume is measured in the range of a pore radius of 20 to 30000 Å by the mercury intrusion method using a mercury porosimeter. When a carrier having a pore volume with a pore radius of 20 Å or more smaller than 0.1 cc / g is used, it tends to be difficult to obtain high polymerization activity.

[0178] It is also preferable to subject clay and clay minerals to chemical treatment. As the chemical treatment, any of surface treatment for removing impurities adhering to the surface, treatment that affects the crystal structure of clay, etc. can be used. Specific examples of the chemical treatment include acid treatment, alkali treatment, salt treatment, organic matter treatment, etc. Acid treatment not only removes surface impurities but also increases the surface area by eluting cations such as Al, Fe, Mg, etc. in the crystal structure. In alkali treatment, the crystal structure of clay is destroyed, resulting in a change in the structure of clay. Also, in salt treatment and organic matter treatment, ion complexes, molecular complexes, organic derivatives, etc. can be formed, and the surface area and interlayer distance can be changed.

[0179] The ion-exchangeable layered compound may be a layered compound in a state where the interlayer is expanded by utilizing the ion-exchangeability and exchanging the exchangeable ions in the interlayer with another large and bulky ion. Such a bulky ion plays a pillar-like role in supporting the layered structure and is usually called a pillar. Also, introducing another substance into the interlayer of the layered compound in this way is called intercalation. Examples of guest compounds for intercalation include cationic inorganic compounds such as TiCl4 and ZrCl4, metal alkoxides such as Ti(OR)4, Zr(OR)4, PO(OR)3, and B(OR)3 (R is a hydrocarbon group, etc.), [Al 13 O4(OH) 24 7+ 、[Zr4(OH) 14 2+ 、[Fe3O(OCOCH3)6] + and other metal hydroxide ions. These compounds can be used alone or in combination of two or more. Also, when intercalating these compounds, polymers obtained by hydrolyzing metal alkoxides such as Si(OR)4, Al(OR)3, Ge(OR)4, etc. (R is a hydrocarbon group, etc.), colloidal inorganic compounds such as SiO2, etc. can also coexist. Also, examples of the pillar include oxides formed by heating and dehydrating after intercalating the above metal hydroxide ions into the interlayer.

[0180] ​​Clay, clay minerals, and ion-exchange layered compounds may be used as they are, or may be used after being processed such as by ball milling or sieving. Further, they may be used after newly adsorbing water or after heat dehydration treatment. Furthermore, they may be used alone or in combination of two or more kinds.

[0181] Among these, preferred ones are clay or clay minerals, and particularly preferred ones are montmorillonite, vermiculite, hectorite, teniolite, and synthetic mica. Examples of the organic compound include granular or fine particulate solids having a particle size in the range of 10 to 300 μm. Specifically, (co)polymers mainly composed of α-olefins having 2 to 14 carbon atoms such as ethylene, propylene, 1-butene, and 4-methyl-1-pentene, (co)polymers mainly composed of vinylcyclohexane or styrene, and modified products thereof can be exemplified.

[0182] The catalyst for olefin polymerization used in the present invention may also contain a crosslinked metallocene compound (a), at least one compound (b) selected from (b-1) an organometallic compound, (b-2) an organoaluminum oxy compound, and (b-3) an ionized ionic compound, and a carrier (c) used as needed.

[0183] <Method for polymerizing monomers in the presence of a catalyst for ethylene·α-olefin·non-conjugated polyene copolymer> When copolymerizing ethylene, an α-olefin having 4 to 20 carbon atoms, and a non-conjugated polyene, the usage and addition order of each component constituting the polymerization catalyst can be arbitrarily selected, and the following methods are exemplified. (1) A method of adding the compound (a) alone to the polymerization vessel. (2) A method of adding the compound (a) and the compound (b) to the polymerization vessel in an arbitrary order. (3) A method of adding a catalyst component in which the compound (a) is supported on the carrier (c) and the compound (b) to the polymerization vessel in an arbitrary order. (4) A method of adding the compound (b) supported on the carrier (c) and the compound (a) to the polymerization reactor in any order. (5) A method of adding a catalyst component in which the compound (a) and the compound (b) are supported on the carrier (c) to the polymerization reactor.

[0184] In each of the methods (2) to (5) above, at least two of the compound (a), the compound (b), and the carrier (c) may be contacted in advance.

[0185] In each of the methods (4) and (5) above in which the compound (b) is supported, the unsupported compound (b) may be added in any order as necessary. In this case, the compound (b) may be the same as or different from the compound (b) supported on the carrier (c).

[0186] Further, the solid catalyst component in which the compound (a) is supported on the carrier (c) and the solid catalyst component in which the compound (a) and the compound (b) are supported on the carrier (c) may be prepolymerized with an olefin, and a catalyst component may be further supported on the prepolymerized solid catalyst component.

[0187] In the method for producing the ethylene·α-olefin·non-conjugated polyene copolymer (A), the ethylene·α-olefin·non-conjugated polyene copolymer (A) can be produced by copolymerizing ethylene, an α-olefin having 4 to 20 carbon atoms, and a non-conjugated polyene in the presence of the catalyst for the ethylene·α-olefin·non-conjugated polyene copolymer as described above.

[0188] In the present invention, it can be carried out in any of liquid phase polymerization methods such as solution (dissolution) polymerization and suspension polymerization or gas phase polymerization methods.

[0189] Specific examples of the inert hydrocarbon medium used in the liquid phase polymerization method include aliphatic hydrocarbons such as propane, butane, pentane, hexane, heptane, octane, decane, dodecane, and kerosene; alicyclic hydrocarbons such as cyclopentane, cyclohexane, and methylcyclopentane; aromatic hydrocarbons such as benzene, toluene, and xylene; and halogenated hydrocarbons such as ethylene chloride, chlorobenzene, and dichloromethane. These can be used alone or in combination of two or more. In addition, the olefin itself can also be used as a solvent.

[0190] When performing polymerization of ethylene or the like using the catalyst for copolymer as described above, Compound (a) is usually 10 -12 ~10 -2 moles, preferably 10 -10 ~10 -8 moles, per liter of the reaction volume.

[0191] Compound (b-1) is used in an amount such that the molar ratio [(b-1) / M] of Compound (b-1) to all transition metal atoms (M) in Compound (a) is usually 0.01 to 50000, preferably 0.05 to 10000. Compound (b-2) is used in an amount such that the molar ratio [(b-2) / M] of the aluminum atom in Compound (b-2) to all transition metals (M) in Compound (a) is usually 10 to 50000, preferably 20 to 10000. Compound (b-3) is used in an amount such that the molar ratio [(b-3) / M] of Compound (b-3) to the transition metal atom (M) in Compound (a) is usually 1 to 20, preferably 1 to 15.

[0192] In addition, the polymerization temperature of ethylene or the like using such a catalyst for copolymer is usually in the range of -50 to +200 °C, preferably 0 to +200 °C, more preferably in the range of +80 to +200 °C. Although it depends on the achievable molecular weight and polymerization activity of the catalyst system for copolymer used, being at a higher temperature (+80 °C or higher) is desirable from the viewpoint of productivity.

[0193] The polymerization pressure is usually from normal pressure to 10 MPa gauge pressure, preferably from normal pressure to 5 MPa gauge pressure, and the polymerization reaction can be carried out by any of the batch, semi - continuous, and continuous methods. Furthermore, it is also possible to carry out the polymerization in two or more stages with different reaction conditions.

[0194] The molecular weight of the obtained ethylene - based polymer can also be adjusted by introducing hydrogen into the polymerization system or by changing the polymerization temperature. Furthermore, it can also be adjusted by the amount of the compound (b) used. Specifically, examples include triisobutylaluminum, methylaluminoxane, diethylzinc, etc. When adding hydrogen, the appropriate amount is about 0.001 - 100 NL per 1 kg of olefin.

[0195] <Ethylene copolymer composition for fuel cell gasket> The ethylene copolymer composition for fuel cell gasket of the present invention contains 100 - 20 parts by mass, preferably 95 - 50 parts by mass of the above ethylene·α - olefin·non - conjugated polyene copolymer (S), and 0 - 80 parts by mass, preferably 5 - 50 parts by mass of the above ethylene·α - olefin·non - conjugated polyene copolymer (A) [provided that the total of the copolymer (S) and the copolymer (A) is 100 parts by mass].

[0196] When the ethylene copolymer composition for fuel cell gasket of the present invention is the above copolymer (S) alone, it has good fluidity and a fast vulcanization rate (crosslinking rate), so the vulcanization time (crosslinking time) can be shortened. Moreover, the fuel cell gasket obtained by crosslinking the composition has good durability such as compression set and heat - aging resistance.

[0197] On the other hand, when the ethylene copolymer composition for fuel cell gasket of the present invention contains the above copolymer (A), although the fluidity and vulcanization rate (crosslinking rate) decrease somewhat, the fuel cell gasket obtained by crosslinking the composition has better mechanical strength and low - temperature properties while maintaining equivalent durability.

[0198] In addition to the above-mentioned copolymer (S) and the above-mentioned copolymer (A), the ethylene copolymer composition for a fuel cell gasket of the present invention may contain other polymers. Examples of other polymers that require crosslinking include crosslinkable rubbers such as natural rubber, isoprene rubber, butadiene rubber, styrene-butadiene rubber, chloroprene rubber, nitrile rubber, butyl rubber, acrylic rubber, silicone rubber, fluororubber, and urethane rubber. Examples of other polymers that do not require crosslinking include styrenic thermoplastic elastomers (TPS) such as block copolymers of styrene and butadiene (SBS), polystyrene-poly(ethylene-butylene)-polystyrene (SEBS), and polystyrene-poly(ethylene-propylene)-polystyrene (SEPS), olefinic thermoplastic elastomers (TPO), vinyl chloride-based elastomers (TPVC), ester-based thermoplastic elastomers (TPC), amide-based thermoplastic elastomers (TPA), urethane-based thermoplastic elastomers (TPU), and other elastomers such as other thermoplastic elastomers (TPZ). The other polymer can be blended in an amount of usually 100 parts by mass or less, preferably 80 parts by mass or less, based on the total amount of the ethylene·α-olefin·non-conjugated polyene copolymer (S) and the above-mentioned ethylene·α-olefin·non-conjugated polyene copolymer (A): 100 parts by mass.

[0199] The ethylene copolymer composition for a fuel cell gasket of the present invention may contain at least one selected from other additives such as crosslinking aids, vulcanization accelerators, vulcanization aids, softeners, reinforcing agents, antioxidants, inorganic fillers, processing aids, activators, moisture absorbers, heat stabilizers, weather stabilizers, antistatic agents, colorants, lubricants, thickeners, foaming agents, and foaming aids, depending on the purpose. Also, each additive may be used alone or in combination of two or more.

[0200] The ethylene copolymer composition for a fuel cell gasket of the present invention can be prepared by kneading the above-mentioned copolymer (S), the above-mentioned copolymer (A), and other components blended as needed at a desired temperature using a kneader such as a mixer, a kneader, or a roll.

[0201] Specifically, using a conventionally well-known kneader such as a mixer or a kneader, the above copolymer (S), the above copolymer (A), and, if necessary, other components are kneaded at a predetermined temperature and time, for example, at 80 to 200°C for 3 to 30 minutes. Then, to the obtained kneaded product, other components that are used as necessary, such as a crosslinking agent, are added as necessary, and kneaded at a predetermined temperature and time using a roll, for example, at a roll temperature of 30 to 80°C for 1 to 30 minutes, whereby the ethylene copolymer composition for a fuel cell gasket of the present invention can be prepared.

[0202] 〈Crosslinking agent, crosslinking aid, vulcanization accelerator, and vulcanization aid〉 Examples of the crosslinking agent include crosslinking agents generally used when crosslinking rubber, such as organic peroxides, phenol resins, sulfur-based compounds, hydrosilicone-based compounds, amino resins, quinones or their derivatives, amine-based compounds, azo-based compounds, epoxy-based compounds, and isocyanate-based compounds. Among these, organic peroxides and sulfur-based compounds (hereinafter also referred to as "vulcanizing agents") are preferred.

[0203] Examples of the organic peroxide 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-butylperoxybenzoate, tert-butylperoxyisopropyl carbonate, diacetyl peroxide, lauroyl peroxide, and tert-butylcumyl peroxide.

[0204] When an organic peroxide is used as a crosslinking agent, its compounding amount in the ethylene copolymer composition for fuel cell gaskets is generally 0.1 to 20 parts by mass, preferably 0.2 to 15 parts by mass, more preferably 0.5 to 10 parts by mass, based on 100 parts by mass in total of the above copolymer (S), the above copolymer (A), and other polymers (crosslinkable rubbers, etc.) that require crosslinking and are compounded as necessary. When the compounding amount of the organic peroxide is within the above range, the ethylene copolymer composition for fuel cell gaskets exhibits excellent crosslinking characteristics without blooming on the surface of the resulting fuel cell gasket, so it is suitable.

[0205] When an organic peroxide is used as a crosslinking agent, it is preferable to use a crosslinking aid in combination. Examples of crosslinking aids 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; metal oxides such as zinc oxide (for example, two types of zinc oxide (JIS standard (K-1410)), zinc oxide #1, manufactured by Hakusuitech Co., Ltd.), magnesium oxide, and activated zinc white (for example, zinc oxide such as "META-Z102" (trade name, manufactured by Inoue Lime Industry Co., Ltd.)).

[0206] When a crosslinking aid is used, the compounding amount of the crosslinking aid in the ethylene copolymer composition for fuel cell gaskets is usually 0.5 to 10 moles, preferably 0.5 to 7 moles, more preferably 1 to 6 moles, per 1 mole of the organic peroxide.

[0207] Examples of sulfur-based compounds (vulcanizing agents) include sulfur, sulfur chloride, sulfur dichloride, morpholine disulfide, alkylphenol disulfide, tetramethylthiuram disulfide, and selenium dithiocarbamate.

[0208] When a sulfur-based compound is used as a crosslinking agent, the blending amount thereof in the ethylene copolymer composition for fuel cell gaskets is usually 0.3 to 10 parts by mass, preferably 0.5 to 7.0 parts by mass, more preferably 0.7 to 5.0 parts by mass with respect to a total of 100 parts by mass of the above copolymer (S), the above polymer (A), and other polymers (crosslinkable rubbers, etc.) that require crosslinking and are blended as necessary. When the blending amount of the sulfur-based compound is within the above range, there is no bloom on the surface of the resulting fuel cell gasket, and the ethylene copolymer composition for fuel cell gaskets exhibits excellent crosslinking characteristics.

[0209] When a sulfur-based compound is used as a crosslinking agent, it is preferable to use a vulcanization accelerator in combination. Examples of the vulcanization accelerator include thiazole-based vulcanization accelerators such as N-cyclohexyl-2-benzothiazolesulfenamide, N-oxydiethylene-2-benzothiazolesulfenamide, N,N'-diisopropyl-2-benzothiazolesulfenamide, 2-mercaptobenzothiazole (e.g., Sanseler M (trade name; manufactured by Sanshin Chemical Industry Co., Ltd.)), 2-(4-morpholinodithio) benzothiazole (e.g., Nocceler MDB-P (trade name; manufactured by Ouchi Shinko Chemical Industry Co., Ltd.)), 2-(2,4-dinitrophenyl) mercaptobenzothiazole, 2-(2,6-diethyl-4-morpholinothio) benzothiazole, and dibenzothiazyl disulfide (e.g., Sanseler DM (trade name; manufactured by Sanshin Chemical Industry Co., Ltd.)); guanidine-based vulcanization accelerators such as diphenylguanidine, triphenylguanidine, and diorthotolylguanidine; aldehydeamine-based vulcanization accelerators such as acetaldehyde aniline condensate and butyraldehyde aniline condensate; imidazoline-based vulcanization accelerators such as 2-mercaptoimidazoline; thiuram-based vulcanization accelerators such as tetramethylthiuram monosulfide (e.g., Sanseler TS (trade name; manufactured by Sanshin Chemical Industry Co., Ltd.)), tetramethylthiuram disulfide (e.g., Sanseler TT (trade name; manufactured by Sanshin Chemical Industry Co., Ltd.)), tetraethylthiuram disulfide (e.g., Sanseler TET (trade name; manufactured by Sanshin Chemical Industry Co., Ltd.)), tetrabutylthiuram disulfide (e.g., Sanseler TBT (trade name; manufactured by Sanshin Chemical Industry Co., Ltd.)), and dipentamethylenethiuram tetrasulfide (e.g., Sanseler TRA (trade name; manufactured by Sanshin Chemical Industry Co., Ltd.)); dithiocarbamate-based vulcanization accelerators such as zinc dimethyldithiocarbamate, zinc diethyldithiocarbamate, zinc dibutyldithiocarbamate (e.g., Sanseler PZ, Sanseler BZ, and Sanseler EZ (trade names; manufactured by Sanshin Chemical Industry Co., Ltd.)), and tellurium diethyldithiocarbamate; thiourea-based vulcanization accelerators such as ethylene thiourea (e.g., Sanseler BUR (trade name; manufactured by Sanshin Chemical Industry Co., Ltd.), Sanseler 22-C (trade name; manufactured by Sanshin Chemical Industry Co., Ltd.)), N,N'-diethylthiourea, and N,N'-dibutylthiourea; and xanthate-based vulcanization accelerators such as zinc dibutylxanthate.

[0210] When using a vulcanization accelerator, the compounding amount of these vulcanization accelerators in the ethylene copolymer composition for fuel cell gaskets is generally 0.1 to 20 parts by mass, preferably 0.2 to 15 parts by mass, and more preferably 0.5 to 10 parts by mass with respect to a total of 100 parts by mass of the above copolymer (S), the above copolymer (A), and other polymers (crosslinkable rubbers, etc.) that require crosslinking and are compounded as necessary. When the compounding amount of the vulcanization accelerator is within the above range, the ethylene copolymer composition for fuel cell gaskets exhibits excellent crosslinking characteristics without blooming on the surface of the resulting fuel cell gasket.

[0211] When using a sulfur-based compound as a crosslinking agent, a vulcanization aid can be used in combination. Examples of the vulcanization aid include zinc oxide (for example, two types of zinc oxide, ZnO#1, manufactured by Hakusuitec Co., Ltd.), magnesium oxide, and activated zinc white (for example, zinc oxide such as "META-Z102" (trade name; manufactured by Inoue Sekkai Kogyo Co., Ltd.)).

[0212] When using a vulcanization aid, the compounding amount of the vulcanization aid in the ethylene copolymer composition for fuel cell gaskets is usually 1 to 20 parts by mass with respect to a total of 100 parts by mass of the above copolymer (S), the above copolymer (A), and other polymers (crosslinkable rubbers, etc.) that require crosslinking and are compounded as necessary.

[0213] 〈Softening agent〉 Examples of the softening agent include petroleum-based softening agents such as process oil, lubricating oil, paraffin oil, liquid paraffin, petroleum asphalt, and petrolatum; coal tar-based softening agents such as coal tar; fatty oil-based softening agents such as castor oil, linseed oil, rapeseed oil, soybean oil, and coconut oil; waxes such as beeswax and carnauba wax; naphthenic acid, pine oil, rosin or its derivatives; synthetic polymer substances such as terpene resin, petroleum resin, and coumarone-indene resin; ester-based softening agents such as dioctyl phthalate and dioctyl adipate; and others such as microcrystalline wax, liquid polybutadiene, modified liquid polybutadiene, hydrocarbon-based synthetic lubricating oil, tall oil, and factice. Among these, petroleum-based softening agents are preferred, and process oil is particularly preferred.

[0214] When the ethylene copolymer composition for a fuel cell gasket contains a softening agent, the blending amount of the softening agent is generally 0 to 100 parts by mass, preferably 0 to 80 parts by mass, based on 100 parts by mass in total of the above copolymer (S), the above copolymer (A), and other polymers (elastomers, crosslinkable rubbers, etc.) blended as necessary.

[0215] 〈Reinforcing agent〉 Examples of the reinforcing agent include carbon black, carbon black surface-treated with a silane coupling agent, silica, calcium carbonate, activated calcium carbonate, fine powder talc, and fine powder silicic acid.

[0216] When the ethylene copolymer composition for a fuel cell gasket contains a reinforcing agent, the blending amount of the reinforcing agent is generally 5 to 150 parts by mass, preferably 5 to 100 parts by mass, based on 100 parts by mass in total of the above copolymer (S), the above copolymer (A), and other polymers (elastomers, crosslinkable rubbers, etc.) blended as necessary.

[0217] 〈Antioxidant (stabilizer)〉 By blending an antioxidant (stabilizer) into the ethylene copolymer composition for a fuel cell gasket of the present invention, the life of the fuel cell gasket to be formed therefrom can be prolonged. Examples of such antioxidants include conventionally known antioxidants, such as amine-based antioxidants, phenol-based antioxidants, and sulfur-based antioxidants.

[0218] Examples of the anti-aging agent include aromatic secondary amine-based anti-aging agents such as phenylbutylamine and N,N-di-2-naphthyl-p-phenylenediamine; phenolic anti-aging agents such as dibutylhydroxytoluene and tetrakis[methylene(3,5-di-t-butyl-4-hydroxy)hydrocinnamate]methane; thioether-based anti-aging agents such as bis[2-methyl-4-(3-n-alkylthiopropionyloxy)-5-t-butylphenyl]sulfide; dithiocarbamate-based anti-aging agents such as nickel dibutyldithiocarbamate; sulfur-based anti-aging agents such as 2-mercaptobenzoyl imidazole, 2-mercaptobenzimidazole, zinc salt of 2-mercaptobenzimidazole, dilauryl thiodipropionate, and distearyl thiodipropionate, etc.

[0219] When the ethylene copolymer composition for fuel cell gaskets contains an anti-aging agent, the compounding amount of the anti-aging agent is usually 0.3 to 10 parts by mass, preferably 0.5 to 7.0 parts by mass, based on 100 parts by mass in total of the above copolymer (S), the above copolymer (A), and other polymers (elastomers, crosslinkable rubbers, etc.) compounded as required. When the compounding amount of the anti-aging agent is within the above range, there is no bloom on the surface of the resulting fuel cell gasket, and furthermore, the occurrence of vulcanization inhibition can be suppressed.

[0220] 〈Inorganic filler〉 Examples of the inorganic filler include light calcium carbonate, heavy calcium carbonate, talc, clay, etc. Among these, heavy calcium carbonate such as "Whiteon SB" (trade name; Shiraishi Calcium Co., Ltd.) is preferred.

[0221] When the ethylene copolymer composition for a fuel cell gasket contains an inorganic filler, the compounding amount of the inorganic filler is usually 2 to 50 parts by mass, preferably 5 to 50 parts by mass, based on 100 parts by mass in total of the copolymer (S), the copolymer (A), and other polymers (elastomers, crosslinkable rubbers, etc.) compounded as necessary. When the compounding amount of the inorganic filler is within the above range, the kneading processability of the ethylene copolymer composition for a fuel cell gasket is excellent, and a fuel cell gasket excellent in mechanical properties can be obtained.

[0222] 〈Processing aid〉 As the processing aid, for example, those generally compounded with rubber as a processing aid can be widely used.

[0223] Specific examples of the processing aid include fatty acids such as ricinoleic acid, stearic acid, palmitic acid, and lauric acid; fatty acid salts such as barium stearate, zinc stearate, and calcium stearate; and esters. Among these, stearic acid is preferred.

[0224] When the ethylene copolymer composition for a fuel cell gasket contains a processing aid, the compounding amount of the processing aid is usually 10 parts by mass or less, preferably 8.0 parts by mass or less, based on 100 parts by mass in total of the copolymer (S), the copolymer (A), and other polymers (elastomers, crosslinkable rubbers, etc.) compounded as necessary.

[0225] 〈Activator〉 Examples of the activator include amines such as di-n-butylamine, dicyclohexylamine, and monoethanolamine; activators such as diethylene glycol, polyethylene glycol, lecithin, triallyl trimellitate, and zinc compounds of aliphatic carboxylic acids or aromatic carboxylic acids; zinc peroxide preparations; and cetadecyl trimethylammonium bromide, synthetic hydrotalcite, and special quaternary ammonium compounds.

[0226] When the ethylene copolymer composition for a fuel cell gasket contains an activator, the compounding amount of the activator is usually 0.2 to 10 parts by mass, preferably 0.3 to 5 parts by mass, based on 100 parts by mass in total of the above copolymer (S), the above copolymer (A), and other polymers (elastomers, crosslinkable rubbers, etc.) compounded as necessary.

[0227] 〈Desiccant〉 Examples of the desiccant include calcium oxide, silica gel, sodium sulfate, molecular sieve, zeolite, and white carbon.

[0228] When the ethylene copolymer composition for a fuel cell gasket contains a desiccant, the compounding amount of the desiccant is usually 0.5 to 15 parts by mass, preferably 1.0 to 12 parts by mass, based on 100 parts by mass in total of the above copolymer (S), the above copolymer (A), and other polymers (elastomers, crosslinkable rubbers, etc.) compounded as necessary.

[0229] 〈Blowing agent and blowing aid〉 The seal packing formed using the ethylene copolymer composition for a fuel cell gasket of the present invention may be a non-foamed body or a foamed body. When the fuel cell gasket is a foamed body, it is preferable that the ethylene copolymer composition for a fuel cell gasket contains a blowing agent.

[0230] As the foaming agent, any commercially available foaming agent can be preferably used. Examples of such foaming agents include inorganic foaming agents such as sodium bicarbonate, sodium carbonate, ammonium bicarbonate, ammonium carbonate, ammonium nitrite, etc.; nitroso compounds such as N,N'-dinitrosoterephthalamide, N,N'-dinitrosopentamethylenetetramine, etc.; azo compounds such as azodicarbonamide, azobisisobutyronitrile, azocyclohexylnitrile, azodiaminobenzene, barium azodicarboxylate, etc.; sulfonyl hydrazide compounds such as benzenesulfonyl hydrazide, toluenesulfonyl hydrazide, p,p'-oxybis(benzenesulfonyl hydrazide), diphenyl sulfone-3,3'-disulfonyl hydrazide, etc.; and azide compounds such as calcium azide, 4,4'-diphenyldisulfonyl azide, paratoluenemalonyl azide, etc. Among them, azo compounds, sulfonyl hydrazide compounds, and azide compounds are preferably used.

[0231] When the ethylene copolymer composition for fuel cell gaskets contains a foaming agent, the blending amount of the foaming agent is appropriately selected according to the performance required for the fuel cell gasket produced from the ethylene copolymer composition for fuel cell gaskets. However, it is usually used in a proportion of 0.1 to 30 parts by mass, preferably 0.2 to 20 parts by mass, based on 100 parts by mass in total of the above copolymer (S), the above copolymer (A), and other polymers (elastomers, crosslinkable rubbers, etc.) blended as required.

[0232] Also, a foaming aid may be used in combination with the foaming agent as required. The addition of the foaming aid is effective in adjusting the decomposition temperature of the foaming agent and homogenizing the bubbles. Specific examples of the foaming aid include organic acids such as salicylic acid, phthalic acid, stearic acid, oxalic acid, etc., urea and its derivatives, etc.

[0233] When the ethylene copolymer composition for fuel cell gaskets contains a foaming aid, the blending amount of the foaming aid is usually used in a proportion of 1 to 100 parts by mass, preferably 2 to 80 parts by mass, based on 100 parts by mass of the foaming agent.

[0234] By using the ethylene copolymer composition for fuel cell gaskets of the present invention, it is possible to obtain a fuel cell gasket having excellent low-temperature flexibility compared to the case of using conventional EPDM, and it is possible to obtain a fuel cell gasket having excellent cold resistance compared to the case of using silicone rubber.

[0235] <Fuel cell gasket> The fuel cell gasket of the present invention is formed from the ethylene copolymer composition for fuel cell gaskets described above.

[0236] As a method for manufacturing a fuel cell gasket from the ethylene copolymer composition for fuel cell gaskets of the present invention, for example, there is a method in which the ethylene copolymer composition for fuel cell gaskets is molded into a desired fuel cell gasket shape, and simultaneously with or after this molding, the composition is crosslinked.

[0237] As a method for crosslinking, for example, there are a method in which a composition containing a crosslinking agent is used as the ethylene copolymer composition for fuel cell gaskets and crosslinked by heating, and a method in which the ethylene copolymer composition for fuel cell gaskets is crosslinked by irradiating with an electron beam.

[0238] That is, the fuel cell gasket of the present invention is obtained by molding the ethylene copolymer composition for fuel cell gaskets into a desired shape using a molding machine such as an extrusion molding machine, calender roll, press, injection molding machine, or transfer molding machine, and crosslinking simultaneously with the molding or by introducing the molded product into a vulcanization tank and heating at 120 to 270 °C for 1 to 30 minutes or by irradiating with an electron beam.

[0239] When crosslinking, a mold may be used, or crosslinking may be carried out without using a mold. When not using a mold, the molding and crosslinking steps are usually carried out continuously. As a heating method in the vulcanization tank, means such as hot air, glass bead fluidized bed, UHF (extremely high frequency electromagnetic wave), and steam can be used.

[0240] When an electron beam is used as a crosslinking method without using a crosslinking agent, an electron beam having an energy of usually 0.1 to 10 MeV, preferably 0.3 to 2 MeV, is applied to an ethylene copolymer composition for a fuel cell gasket formed into a predetermined shape so that the absorbed dose is usually 0.5 to 35 Mrad, preferably 0.5 to 10 Mrad.

[0241] The fuel cell gasket of the present invention is a fuel cell gasket used for a hydrogen line. At a hydrogen station that supplies hydrogen to a fuel cell vehicle or the like, there are a large number of hydrogen lines through which hydrogen passes. The fuel cell gasket of the present invention is used as a fuel cell gasket used for such a hydrogen line.

[0242] At a hydrogen station, in order to store a large amount of hydrogen, it is necessary to store it in a compressor at a high pressure. In addition, when supplying hydrogen from a hydrogen station, it is necessary to send it out at a high pressure and high speed, and at this time the temperature of hydrogen rises. In order not to raise the temperature in the hydrogen tank of a fuel cell vehicle or the like too much, it is necessary to store hydrogen at a low temperature, for example, about -40°C, at a hydrogen station. For this reason, the fuel cell gasket used for a hydrogen line is required to have sealing performance at a low temperature. The fuel cell gasket of the present invention has both low temperature characteristics and mechanical strength (strength and elongation), and can be suitably used for a hydrogen line.

Examples

[0243] Hereinafter, the present invention will be described more specifically based on examples, but the present invention is not limited to these examples. Unless otherwise specified, "parts" represents "parts by mass". The following copolymers were used in the examples and comparative examples.

[0244] 〔Ethylene·α-olefin·non-conjugated polyene copolymer (S)〕 Production of copolymer (S-1) <Production of ethylene·propylene·VNB copolymer> In the method for producing an ethylene·propylene·VNB copolymer described in Example 1 (

[0386] ~

[0391] ) of International Publication No. 2019 / 180802, the ethylene·propylene·VNB copolymer (S-1) shown in Table 1 below was produced by adjusting the hydrogen feed amount.

[0245]

Table 1

[0246] <Molar amounts of structural units derived from ethylene, structural units derived from α-olefin, and structural units derived from non-conjugated polyene> The molar amounts were 1 determined by intensity measurement using an H-NMR spectrometer. Details of the measurement conditions are described in International Publication No. 2015 / 122415.

[0247] <Mooney viscosity> The Mooney viscosity (ML(1+4)100 °C) was measured in accordance with JIS K6300 (1994) using a Mooney viscometer (Model SMV202 manufactured by Shimadzu Corporation).

[0248] Using o-dichlorobenzene-d4 / benzene-d6 (4 / 1 [v / v]) as the measurement solvent and a measurement temperature of 120 °C, 13 a 13C-NMR spectrum (100 MHz, Model 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 [A1], α-olefin [A2] having 3 to 20 carbon atoms, and non-conjugated polyene [A3], respectively, and [EX] represents the ethylene [A1]-α-olefin [A2] having 3 to 20 carbon atoms dyad chain fraction.]

[0249] As the ethylene·α-olefin·non-conjugated polyene copolymer (A), the following ethylene·α-olefin·non-conjugated polyene copolymer [copolymer (A-1)] was used. According to the description of [Synthesis Example C1] in International Publication No. 2015 / 122415, an ethylene / 1-butene / 5-ethylidene-2-norbornene (ENB) copolymer having the following physical properties was obtained. Hereinafter, this will be referred to as "copolymer (A-1)".

[0250] The composition and physical properties of the copolymer (A-1) are as follows. Structural unit derived from ethylene: 67.7 mol% Structural unit derived from 1-butene: 30.0 mol% Structural unit derived from ENB: 2.3 mol% Mooney viscosity ML(1+4) 100°C: 30 B value: 1.3

[0251] [Example 1] 《Ethylene Copolymer Composition for Fuel Cell Gasket》 Using a MIXTRON BB MIXER (manufactured by Kobe Steel, Ltd., BB-4 type, volume 2.95L, rotor 4WH), for 25 parts of copolymer (S-1) and 75 parts of copolymer (A-1) [copolymer (S-1) + copolymer (A-1) = 100 parts], active zinc white (trade name META Z-102, manufactured by Inoue Lime Industry Co., Ltd.): 5 parts, stearic acid: 1 part, carbon black "Asahi #60UG" (trade name; manufactured by Asahi Carbon Co., Ltd.): 50 parts, as an antioxidant, Sandant MB (2-mercaptobenzimidazole, manufactured by Sanshin Chemical Industry Co., Ltd.): 6 parts, as an antioxidant, Irganox 1010 (dibutylhydroxytoluene, tetrakis[methylene(3,5-di-t-butyl-4-hydroxy)hydrocinnamate]methane, manufactured by BASF): 3 parts were blended and then kneaded to obtain Blend 1.

[0252] The kneading conditions were a rotor rotation speed of 50 rpm, a floating weight pressure of 3 kg / cm 2 , and the kneading time was 5 minutes, and the kneading discharge temperature was 150°C. Next, after confirming that the temperature of Formulation 1 reached 40°C, using a 6-inch roll, 2,5-dimethyl-2,5-di-(tert-butylperoxy)hexane [trade name: Perhexa 25B, manufactured by NOF Corporation] and Kayaku Mil D-40C (40% by mass of dicumyl peroxide, manufactured by Chemische Fabrik Budenheim KG): 7.3 parts were added to Formulation 1 as a crosslinking agent (vulcanizing agent) and kneaded to obtain Formulation 2.

[0253] The kneading conditions were as follows: the roll temperature was set at front roll / rear roll = 50°C / 50°C, the peripheral speed of the rolls was set at front roll / rear roll = 18 rpm / 15 rpm, the roll gap was 3 mm, and the kneading time was 8 minutes, after which the mixture was discharged to obtain Formulation 2.

[0254] 〔Unvulcanized Physical Property Test 1: Mooney Viscosity〕 The Mooney viscosity ML of Formulation 2 (1+4) at 100°C was measured in accordance with JIS K6300 (1994) using a Mooney viscometer (Model SMV202, manufactured by Shimadzu Corporation).

[0255] 〔Unvulcanized Physical Property Test 2: Vulcanization Characteristics Evaluation〕 Using a vulcanization measuring device: MDR2000 (manufactured by ALPHA TECHNOLOGIES), the vulcanization rate (tC90) of Formulation 2 at 180°C was measured as follows.

[0256] The torque change obtained under the conditions of a constant temperature and a constant shear rate was measured. The time required to reach 90% of the torque, which is the difference between the maximum value (S'Max) and the minimum value (S'Min) of the torque, was defined as TC90 (min). The measurement conditions were a temperature of 180°C and a time of 15 minutes. The smaller this TC90 value, the faster the vulcanization rate (crosslinking rate).

[0257] 《Evaluation of Vulcanizate (Crosslinked Product)》 Using a press molding machine, Formulation 2 was crosslinked at 180°C for 10 minutes to prepare a 2-mm thick sheet (vulcanizate).

[0258] For the obtained sheet, a hardness test, a tensile test, a heat aging resistance test, and a T-R test were conducted according to the following methods. For Compound 2, using a press molding machine equipped with a cylindrical mold, vulcanization was carried out at 180 °C for 13 minutes to prepare a straight cylindrical test piece with a thickness of 12.7 mm and a diameter of 29 mm, and a test piece for the compression set (CS) test (vulcanizate) was obtained. Using the obtained test piece for the compression set (CS) test, the compression set was evaluated according to the following method. The results are shown in Table 2.

[0259] 〔Hardness Test: Hardness (Durometer-A)〕 The hardness of the sheet was measured in accordance with the description of "Hardness Test" in Section 7 of "Physical Test Methods for Thermosetting Polyurethane Elastomer Moldings" of JIS K7312 (1996) and the description of Test Type A of "Durometer Hardness Test" in Section 6 of JIS K6253 (2006) "Vulcanized Rubber and Thermoplastic Rubber - Method for Determining Hardness".

[0260] 〔Tensile Test: Modulus, Tensile Break Stress, Tensile Break Elongation〕 The modulus, tensile break stress, and tensile break elongation of the sheet were measured by the following method. The sheet was punched out to prepare a No. 3 dumbbell test piece described in JIS K6251 (1993). Using this test piece, a tensile test was conducted under the conditions of a measurement temperature of 25 °C and a tensile speed of 500 mm / min according to the method specified in Section 3 of JIS K6251. The tensile stress (25% modulus (M25)), tensile stress (50% modulus (M50)), tensile stress (100% modulus (M100)), tensile break stress (TB), and tensile break elongation (EB) were measured when the elongation rate was 25%, 50%, and 100%, respectively.

[0261] 〔Heat Aging Resistance Test〕 The sheet was subjected to a heat aging test in accordance with JIS K6257 by holding it at 180 °C for 168 hours. The hardness, tensile breaking point stress, and tensile breaking point elongation of the sheet after the heat aging test were measured in the same manner as in the items of [Hardness (Durometer-A)] and [Modulus, Tensile Breaking Point Stress, Tensile Breaking Point Elongation].

[0262] From the difference in hardness before and after the heat aging test, AH (Duro-A) was determined. From the tensile breaking point stress (TB) and tensile breaking point elongation (EB) before and after the heat aging test, the change rates after the test with respect to the values before the heat aging test were determined as Ac (TB) and Ac (EB), respectively.

[0263] [T-R Test (Low Temperature Elastic Recovery Test)] In accordance with JIS K6261, a T-R test (low temperature elastic recovery test) was performed on the sheet to measure the cold resistance.

[0264] In this test, the extended sheet was frozen, and the recoverability of the extended sheet was measured by continuously increasing the temperature. (The temperatures at which the length of the test piece shrinks (recovers) by 10% and 65% due to the temperature increase are denoted as TR-10 and TR-65, respectively.) The lower the TR-10 (unit: °C), the better the cold resistance can be judged.

[0265] [Examples 2 to 4] The procedure was the same as in Example 1, except that the amounts of the copolymer (S-1) and the copolymer (A-1) used in Example 1 were changed to the amounts shown in Table 〇. The results are shown in Table 2.

[0266] [Comparative Example 1] The procedure was the same as in Example 1, except that the copolymer (A-1) was used alone instead of the mixture of the copolymer (S-1) and the copolymer (A-1) used in Example 1. The results are shown in Table 2.

[0267]

Table 2

[0268] As is clear from Table 2, the composition (Example 4) consisting of 100 parts by mass of the copolymer (S-1) has a lower Mooney viscosity, is excellent in fluidity, has a faster vulcanization rate compared to the composition (Comparative Example 1) consisting of 100 parts by mass of the copolymer (A-1), and the resulting vulcanizate is excellent in durability such as heat aging resistance and compression set.

[0269] The compositions containing the copolymer (A-1) (Examples 1 to 3) have slightly lower fluidity and vulcanization rate compared to Example 4, but are superior in fluidity and vulcanization rate compared to Comparative Example 1. Further, the resulting vulcanizates maintain equivalent durability compared to Example 4 while having better mechanical strength and low temperature properties.

[0270] Among them, the compositions obtained in Examples 1 and 2 have a good balance of fluidity, vulcanization rate, and the durability, mechanical strength, and low temperature properties of the resulting vulcanizates.

Claims

1. It has structural units derived from ethylene (A), an α-olefin (B) having 3 to 20 carbon atoms, and a non-conjugated polyene (C) containing two or more substructures selected from the group consisting of the following general formulas (I) and (II) in the molecule, and 100 to 20 parts by mass of an ethylene / α-olefin / non-conjugated polyene copolymer (S) that satisfies the following requirements (i) to (vi): It contains 0 to 80 parts by mass of an ethylene / α-olefin / non-conjugated polyene copolymer (A) having a structural unit derived from ethylene [A1], a structural unit derived from an α-olefin [A2] having 4 to 20 carbon atoms, and a structural unit derived from a non-conjugated polyene [A3], and satisfying the following requirements (1) to (3) [However, the total of the copolymer (S) and the copolymer (A) is 100 parts by mass]. An ethylene copolymer composition for a fuel cell gasket, characterized in that: 【Chemical 1】 〔Requirements for the ethylene / α-olefin / non-conjugated polyene copolymer (S)〕 (i) The molar ratio [(A) / (B)] of the structural unit derived from ethylene (A) and the structural unit derived from α-olefin (B) is 40 / 60 to 99.9 / 0.1; (ii) The mass fraction of the structural unit derived from the non-conjugated polyene (C) is 0.07% by mass to 10% by mass in 100% by mass of the copolymer (S); (iii) The weight average molecular weight (Mw) of the copolymer (S), the weight fraction of the structural unit derived from the non-conjugated polyene (C) ((weight fraction of (C) (wt%)), and the molecular weight of the non-conjugated polyene (C) ((molecular weight of (C)) satisfy the following formula (1); 4.5 ≤ Mw × (mass fraction of (C) / 100) / (molecular weight of (C)) ≤ 40... Formula (1) (iv) The ratio P (η*(ω = 0.1) / η*(ω = 100)) of the complex viscosity η*(ω = 0.1) (Pa·sec) at a frequency ω = 0.1 rad / s and the complex viscosity η*(ω = 100) (Pa·sec) at a frequency ω = 100 rad / s obtained by linear viscoelastic measurement (190 °C) using a rheometer, the intrinsic viscosity [η], and the mass fraction of the structural unit derived from the non-conjugated polyene (C) ((mass fraction of (C)) satisfy the following formula (2); P / ([η] 2.9 ) ≤ (C) mass fraction × 6... Equation (2) (v) The ratio of the weight average molecular weight (Mw) to the number average molecular weight (Mn) (molecular weight distribution; Mw / Mn) measured by gel permeation chromatography (GPC) is in the range of 4 to 80; (vi) The number average molecular weight (Mn) is 30,000 or less. 〔Requirements for Ethylene / α-Olefin / Non-Conjugated Polyene Copolymer (A)〕 (1) The molar ratio of the structural unit derived from ethylene [A1] to the structural unit derived from an α-olefin having 4 to 20 carbon atoms [A2], [A1] / [A2], is 40 / 60 to 90 / 10, (2) The content ratio of the structural unit derived from non-conjugated polyene [A3] is 0.1 to 6.0 mol% with respect to 100 mol% of the total of the structural units derived from [A1], [A2], and [A3], (3) The B value represented by the following formula (i) is 1.20 or more. B value = ([EX] + 2[Y]) / [2×[E]×([X] + [Y])]... (i) [Here, [E], [X], and [Y] represent the mole fractions of the structural units derived from ethylene [A1], an α-olefin having 4 to 20 carbon atoms [A2], and non-conjugated polyene [A3], respectively, and [EX] represents the ethylene [A1]-α-olefin having 4 to 20 carbon atoms [A2] dyad chain fraction.]

2. The ethylene copolymer composition for a fuel cell gasket according to claim 1, wherein the structural unit derived from an α-olefin having 4 to 20 carbon atoms [A2] in the copolymer (A) contains a structural unit derived from 1-butene.

3. The ethylene copolymer composition for a fuel cell gasket according to claim 1 or 2, wherein the non-conjugated polyene (C) in the copolymer (S) contains a structural unit derived from 5-vinyl-2-norbornene.

4. The ethylene copolymer composition for a fuel cell gasket according to any one of claims 1 to 3, further comprising 1 to 30 parts by mass of an organic peroxide per 100 parts by mass in total of the copolymer (S) and the copolymer (A).

5. A gasket for a fuel cell obtained by using the ethylene copolymer composition for a fuel cell gasket according to any one of claims 1 to 4.

6. The gasket for a fuel cell according to claim 5, wherein the gasket for a fuel cell is a crosslinked product.

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