Rubber composition

Abstract

To provide a rubber composition capable of forming a molded article having excellent tensile strength.SOLUTION: A rubber composition contains: at least one copolymer rubber (A) selected from ethylene-α-olefin copolymer rubber and ethylene-α-olefin-nonconjugated polyene copolymer rubber; a modified ethylene-α-olefin copolymer (B) satisfying specific requirements; an inorganic filler (C); and a coupling agent (D). The content of the modified ethylene-α-olefin copolymer (B) is 1 to 100 pts.mass, and the content of the inorganic filler (C) is 1 to 200 pts.mass, based on 100 pts.mass of the copolymer rubber (A). The content rate of the coupling agent (D) is 0.5 to 20 mass% based on the total of 100 mass% of the inorganic filler (C) and the coupling agent (D).SELECTED DRAWING: None

Description

[Technical field]

[0001] The present disclosure relates to a rubber composition. [Background technology]

[0002] Modifiers such as softeners may be blended into rubber compositions for the purpose of improving processability and moldability, and adjusting rubber physical properties such as hardness and flexibility (see, for example, Patent Documents 1 and 2). Mineral oils refined from crude oil and synthetic oils are used as softeners. In addition, inorganic fillers may be blended into rubber compositions for the purpose of improving mechanical properties. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 61-246215 [Patent Document 2] Patent Publication No. 2021-024912 Summary of the Invention [Problem to be solved by the invention]

[0004] According to the investigations of the present inventors, molded articles formed from conventional rubber compositions containing ethylene-α-olefin copolymer rubber etc. sometimes have insufficient tensile strength. One of the objects of the present disclosure is to provide a rubber composition capable of forming a molded article having excellent tensile strength. [Means for solving the problem]

[0005] One aspect of the rubber composition of the present disclosure contains one or more copolymer rubbers (A) selected from ethylene-α-olefin copolymer rubber and ethylene-α-olefin-non-conjugated polyene copolymer rubber, a modified ethylene-α-olefin copolymer (B) that satisfies specific requirements, an inorganic filler (C), and a coupling agent (D). With respect to 100 parts by mass of the copolymer rubber (A), the content of the modified ethylene-α-olefin copolymer (B) is 1 to 100 parts by mass, the content of the inorganic filler (C) is 1 to 200 parts by mass, and the content ratio of the coupling agent (D) is 0.5 to 20% by mass in the total 100% by mass of the inorganic filler (C) and the coupling agent (D).

Effects of the Invention

[0006] According to the present disclosure, it is possible to provide a rubber composition capable of forming a molded body excellent in tensile strength.

Modes for Carrying Out the Invention

[0007] In this specification, "N1~N2" indicating a numerical range means "N1 or more and N2 or less" unless otherwise specified. N1 and N2 are each arbitrary numbers satisfying the condition of N1 < N2.

[0008] In this specification, the description "(meth)acryl" is used in the sense of including acryl and methacryl. That is, "(meth)acryl" may be acryl, may be methacryl, or may be both acryl and methacryl.

[0009] [Rubber Composition and Method for Producing the Same] The rubber composition of the present disclosure contains one or more copolymer rubbers (A) selected from ethylene-α-olefin copolymer rubbers and ethylene-α-olefin-non-conjugated polyene copolymer rubbers, a modified ethylene-α-olefin copolymer (B) described below, an inorganic filler (C), and a coupling agent (D). By using a rubber composition containing the copolymer rubber (A), the modified ethylene-α-olefin copolymer (B), the inorganic filler (C), and the coupling agent (D) preferably within the ranges described below, a molded article having excellent tensile properties (for example, tensile strength such as tensile strength at break) can be formed.

[0010] The method for producing a rubber composition of the present disclosure includes a step of mixing one or more kinds of copolymer rubber (A) selected from ethylene-α-olefin copolymer rubbers and ethylene-α-olefin-non-conjugated polyene copolymer rubbers, a modified ethylene-α-olefin copolymer (B) described below, an inorganic filler (C), and a coupling agent (D).

[0011] <Copolymer rubber (A)> The copolymer rubber (A) is at least one selected from the group consisting of ethylene-α-olefin copolymer rubbers and ethylene-α-olefin-non-conjugated polyene copolymer rubbers.

[0012] The copolymer rubber (A) has structural units derived from ethylene and structural units derived from an α-olefin having 3 or more carbon atoms. In the total amount of structural units derived from polymerizable monomers in the copolymer rubber (A), the content of structural units derived from ethylene is preferably 40 to 90 mol%, more preferably 45 to 85 mol%, and even more preferably 50 to 80 mol%, and the content of structural units derived from an α-olefin having 3 or more carbon atoms is preferably 10 to 60 mol%, more preferably 15 to 55 mol%, and even more preferably 20 to 50 mol%. The content of the above structural units is 13 It is measured by C-NMR.

[0013] The α-olefin having 3 or more carbon atoms is preferably an α-olefin having 3 to 20 carbon atoms, more preferably an α-olefin having 3 to 12 carbon atoms, and further preferably an α-olefin having 3 to 8 carbon atoms. Examples of the α-olefin include propylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-heptene, 1-octene, 1-nonene, 1-decene, 1-undecene, 1-dodecene, 1-tridecene, 1-tetradecene, 1-pentadecene, 1-hexadecene, 1-heptadecene, 1-octadecene, 1-nonadecene, 1-eicosene, 9-methyl-1-decene, 11-methyl-1-dodecene, and 12-ethyl-1-tetradecene, and more preferably propylene, 1-butene, 4-methyl-1-pentene, 1-hexene, and 1-octene, and particularly preferably propylene. That is, the copolymer rubber (A) is preferably one or more selected from ethylene-propylene copolymer rubber and ethylene-propylene-non-conjugated polyene copolymer rubber.

[0014] The ethylene-α-olefin-non-conjugated polyene copolymer rubber further has a structural unit derived from a non-conjugated polyene in addition to the structural unit derived from ethylene and the structural unit derived from an α-olefin having 3 or more carbon atoms. In the ethylene-α-olefin-non-conjugated polyene copolymer rubber, the content ratio of the structural unit derived from the non-conjugated polyene is preferably 0.1 to 5 mol%, more preferably 0.3 to 4 mol%, and even more preferably 0.5 to 4 mol%. In this case, the content ratio of the structural unit derived from ethylene is preferably 40 to 89.9 mol%, more preferably 45 to 84.7 mol%, and even more preferably 50 to 79.5 mol%, and the content ratio of the structural unit derived from an α-olefin having 3 or more carbon atoms is preferably 10 to 59.9 mol%, more preferably 15 to 54.7 mol%, and even more preferably 20 to 49.5 mol%. The content ratio of the above structural units is 13 It is measured by C-NMR.

[0015] Examples of the non-conjugated polyenes include linear non-conjugated dienes such as 1,4-hexadiene, 1,6-octadiene, 2-methyl-1,5-hexadiene, 6-methyl-1,5-heptadiene, and 7-methyl-1,6-octadiene; cyclohexadiene, dicyclopentadiene, methyltetrahydroindene, 5-vinyl-2-norbornene, 5-ethylidene-2-norbornene, 5-methylene-2-norbornene, and 5-isopropylidene-2-norbornene. and cyclic non-conjugated dienes such as 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, and 4-ethylidene-8-methyl-1,7-nonadiene. Among these, at least one selected from 5-ethylidene-2-norbornene and 5-vinyl-2-norbornene is preferred.

[0016] The copolymer rubber (A) has at least one structural unit derived from an α-olefin, and may have two or more structural units derived from an α-olefin. The copolymer rubber (A) may have one structural unit derived from a non-conjugated polyene, and may have two or more structural units derived from a non-conjugated polyene. The ethylene, the α-olefin having 3 or more carbon atoms, and the non-conjugated polyene, which are monomers constituting or capable of constituting the copolymer rubber (A), may each be, for example, a monomer derived from a fossil fuel or a monomer derived from biomass, and these monomers may be used alone or in combination of two or more.

[0017] The weight average molecular weight (Mw) of the copolymer rubber (A) determined by gel permeation chromatography (GPC) is preferably 30,000 to 1,000,000, more preferably 50,000 to 500,000, and further preferably 100,000 to 300,000. Such a copolymer rubber (A) tends to have an excellent balance between processability when kneaded with the modified ethylene-α-olefin copolymer (B) or the inorganic filler (C), and tensile properties such as tensile strength of a molded article obtained from the rubber composition.

[0018] Details of the conditions for measuring Mw are described in the Examples section.

[0019] The Mooney viscosity ML(1+4)100°C of the copolymer rubber (A) is preferably 10 to 100, more preferably 20 to 90, and further preferably 30 to 80. The Mooney viscosity is measured by a method in accordance with JIS K6300-1:2013 "Unvulcanized rubber-Physical properties-Part 1: Determination of viscosity and scorch time using a Mooney viscometer."

[0020] The rubber composition of the present disclosure may contain one type of copolymer rubber (A) or may contain two or more types of copolymer rubbers (A). The content of the copolymer rubber (A) in the rubber composition of the present disclosure is preferably 20 to 90 mass%, more preferably 30 to 80 mass%, and further preferably 40 to 70 mass% in 100 mass% of the rubber composition. The rubber composition of such an embodiment tends to be capable of forming a molded article having excellent rubber physical properties such as hardness and flexibility. In the method for producing the rubber composition of the present disclosure, the above "content" is read as "blending ratio".

[0021] <Modified ethylene-α-olefin copolymer (B)> The modified ethylene-α-olefin copolymer (B) (hereinafter also referred to as "modified copolymer (B)") satisfies the requirements (b-1) to (b-3) described below. In one embodiment, the modified copolymer (B) is liquid at 23° C. and 1 atmospheric pressure. The modified copolymer (B) has structural units derived from ethylene and structural units derived from an α-olefin having 3 or more carbon atoms.

[0022] <Requirement (b-1)> In the ethylene-α-olefin copolymer (B') before the modification of the modified copolymer (B) with an organosilicon compound described below, the content of structural units derived from ethylene (hereinafter also referred to as "ethylene content") is 10 to 90 mol %, provided that the sum of the content of structural units derived from ethylene and the content of structural units derived from α-olefins having 3 or more carbon atoms is 100 mol %.

[0023] The copolymer (B') has structural units derived from ethylene and structural units derived from an α-olefin having 3 or more carbon atoms. In one embodiment of the modified copolymer (B), at least a portion of the structural units derived from ethylene (ethylene units) and / or the structural units derived from an α-olefin having 3 or more carbon atoms (α-olefin units) is modified with an organosilicon compound described below. Specifically, at least a portion of the structural units has a moiety derived from an organosilicon compound introduced therein.

[0024] The ethylene content in the copolymer (B') is 10 to 90 mol%, preferably 30 to 80 mol%, more preferably 40 to 60 mol%. The copolymer (B) which is a modified product of such copolymer (B') is low crystalline or amorphous, and has a composition close to that of the copolymer rubber (A) and good compatibility, so that the rubber composition containing the modified copolymer (B) tends to be excellent in flexibility and mechanical properties.

[0025] The ethylene content of the copolymer (B') is 13 It is measured by C-NMR and is determined by identifying and quantifying peaks according to the method employed in the examples described below and the method described in "Polymer Analysis Handbook" (published by Asakura Publishing, pp. 163-170).

[0026] Examples of the α-olefin having 3 or more carbon atoms include α-olefins having 3 to 20 carbon atoms, such as propylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-decene, 1-undecene, 1-dodecene, 1-tridecene, 1-tetradecene, 1-pentadecene, 1-hexadecene, 1-heptadecene, 1-octadecene, 1-nonadecene, and 1-eicosene. Among the α-olefins, α-olefins having 3 to 10 carbon atoms are preferred, propylene and 1-butene are more preferred, and propylene is even more preferred, from the viewpoint of effectively reducing the crystallinity of the copolymer, obtaining a liquid copolymer, and easily obtaining a rubber composition and a molded article that exhibit the above-mentioned desired effects. That is, the modified copolymer (B) is preferably a modified ethylene-propylene copolymer.

[0027] The modified copolymer (B) has at least one type of structural unit derived from an α-olefin, and may have two or more types of structural units derived from an α-olefin. The monomers constituting the modified copolymer (B), ethylene and an α-olefin having 3 or more carbon atoms, may each be, for example, a monomer derived from a fossil fuel or a monomer derived from biomass, and these monomers may be used alone or in combination of two or more.

[0028] <Requirement (b-2)> The weight average molecular weight (Mw) of the modified copolymer (B) determined by gel permeation chromatography (GPC) is 1,000 to 100,000. The Mw of the modified copolymer (B) is 1,000 to 100,000, preferably 2,000 to 50,000, and more preferably 2,000 to 30,000. Such modified copolymer (B) tends to have an excellent balance between processability when kneaded with the copolymer rubber (A) and rubber properties such as flexibility and tensile strength in a molded article obtained from the rubber composition.

[0029] The ratio (Mw / Mn) of the molecular weight distribution of the modified copolymer (B) is preferably 1.4 to 3.0, more preferably 1.4 to 2.9, and further preferably 1.4 to 2.8. A rubber composition containing such a modified copolymer (B) tends to be able to suppress the deterioration of mechanical properties of a molded article due to volatilization of low molecular weight components and / or the bleeding out of low molecular weight components to the surface of the molded article when used in a high temperature environment.

[0030] Mw and Mn are determined by gel permeation chromatography (GPC). Details of the measurement conditions for Mw and Mn are described in the Examples section.

[0031] <Requirement (b-3)> The modified copolymer (B) is a modified copolymer having a moiety derived from an organosilicon compound containing one or more carbon-carbon unsaturated bonds, and the content ratio of the moiety derived from the organosilicon compound in 100% by mass of the modified copolymer is 0.5 to 50% by mass. The content ratio of the moiety is preferably 0.5 to 30% by mass, more preferably 0.5 to 20% by mass, and particularly preferably 0.5 to 19% by mass. A rubber composition containing such a modified copolymer (B) tends to be able to form a molded article having excellent tensile strength. The position of the moiety derived from the organosilicon compound, for example, the graft position of the organosilicon compound, is not particularly limited.

[0032] In one embodiment, the modified copolymer (B) has an ethylene-α-olefin copolymer portion (main chain portion) and a graft portion derived from the organosilicon compound. The ethylene-α-olefin copolymer portion has structural units derived from ethylene and structural units derived from an α-olefin having 3 or more carbon atoms. The ethylene-α-olefin copolymer portion is preferably a random copolymer chain of ethylene and an α-olefin having 3 or more carbon atoms.

[0033] The reason why the rubber composition of the present disclosure can form a molded article having excellent tensile properties such as tensile strength is not clear, but it is presumed to be due to the following reasons. The modified copolymer (B) has a site derived from the above-mentioned organosilicon compound, and therefore reacts with the inorganic filler (C) to form a chemical bond, and the modified copolymer (B) is unevenly distributed on the surface of the inorganic filler (C), which is thought to suppress the aggregation of the inorganic filler (C) in the rubber composition. In addition, since the ethylene-α-olefin copolymer main chain constituting the modified copolymer (B) has excellent compatibility with the copolymer rubber (A), it is thought that the modified copolymer (B) functions as a compatibilizer between the copolymer rubber (A) and the inorganic filler (C), and the dispersibility of the inorganic filler (C) in the rubber composition is improved. Furthermore, in one embodiment, the inorganic filler (C) in a state of excellent dispersibility can be chemically bonded to the copolymer rubber (A) due to the effect of co-crosslinking of the coupling agent (D) and the main chain of the modified copolymer (B) with the copolymer rubber (A). It is presumed that the tensile properties such as the tensile strength of the molded article are improved due to these reasons. In addition, since the coupling agent (D) is usually lower in viscosity than the modified copolymer (B), even if the reactivity of the functional group itself is the same, the reactivity of the molecule itself with respect to the inorganic filler (C) is considered to be higher for the coupling agent (D) than for the modified copolymer (B). Therefore, even if the content of the coupling agent (D) is less than the content of the modified copolymer (B), it is considered that the reaction between the inorganic filler (C) and the coupling agent (D) and the modified copolymer (B) competes. Due to this effect, the aggregation of the inorganic filler (C) via the modified copolymer (B) is suppressed, and it is presumed that the same effect will be exhibited even if the content of the modified copolymer (B) is high. The above reasons are merely speculations and do not limit the rubber composition of the present disclosure in any way.

[0034] The content of the moiety derived from the organosilicon compound in the modified copolymer (B) is 1 The measurement conditions are described in detail in the Examples section.

[0035] The organosilicon compound is preferably a compound having one or more carbon-carbon unsaturated bonds and one or more hydrolyzable groups directly bonded to silicon. The number of carbon-carbon unsaturated bonds in the organosilicon compound is preferably 1 to 3, more preferably 1 to 2, and even more preferably 1. The number of hydrolyzable groups in the organosilicon compound is preferably 1 to 9, more preferably 1 to 6, and even more preferably 1 to 3.

[0036] The organosilicon compound has a group containing the carbon-carbon unsaturated bond. The carbon-carbon unsaturated bond is preferably a carbon-carbon unsaturated double bond. Examples of such groups include alkenyl groups such as vinyl and allyl groups, (meth)acryloyl groups, (meth)acryloxy groups and vinylphenyl groups, with alkenyl groups being preferred, and vinyl groups being more preferred. Examples of hydrolyzable groups include alkoxy groups, alkoxyalkoxy groups, aryloxy groups and acyloxy groups, with alkoxy groups being preferred. The organosilicon compound is preferably an unsaturated silane compound.

[0037] An example of the organosilicon compound is a compound represented by the formula (E1). (X 1 -Y 1 -) a Si(R 1 ) b (R 2 ) c (E1)

[0038] The meanings of the symbols in formula (E1) are as follows. X 1 is an alkenyl group, a (meth)acryloxy group, or a vinylphenyl group, and preferably an alkenyl group. The number of carbon atoms in the alkenyl group is preferably 2 to 10, more preferably 2 to 6, and further preferably 2 to 4. Examples of the alkenyl group include a vinyl group, an allyl group, and an octenyl group.

[0039] Y 1is a direct bond or an alkanediyl group, and is bonded to Si. The number of carbon atoms in the alkanediyl group is preferably 1 to 10, more preferably 1 to 6, and further preferably 1 to 3. Examples of the alkanediyl group include a methanediyl group, an ethanediyl group, a propanediyl group, and an octanediyl group.

[0040] R 1 is an alkoxy group, an alkoxyalkoxy group, an aryloxy group, or an acyloxy group, and is bonded to Si. The number of carbon atoms in the alkoxy group is preferably 1 to 10, more preferably 1 to 6, and even more preferably 1 to 3. The number of carbon atoms in the alkoxyalkoxy group is preferably 2 to 12, more preferably 2 to 8, and even more preferably 2 to 6. The number of carbon atoms in the aryloxy group is preferably 6 to 10. The number of carbon atoms in the acyloxy group is preferably 2 to 10, more preferably 2 to 6, and even more preferably 2 to 4. Examples of the alkoxy group include a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a pentyloxy group, a hexyloxy group, a heptyloxy group, and an octyloxy group. Examples of the alkoxyalkoxy group include a methoxyethoxy group, an ethoxyethoxy group, and a methoxypropoxy group. Examples of the aryloxy group include a phenoxy group. Examples of the acyloxy group include an acetoxy group.

[0041] R 2 is an alkyl group or a substituted or unsubstituted aryl group, and is bonded to Si. The number of carbon atoms in the alkyl group is preferably 1 to 10, more preferably 1 to 6, and further preferably 1 to 4. The number of carbon atoms in the substituted or unsubstituted aryl group is preferably 6 to 12, and more preferably 6 to 8. Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, and an octyl group. Examples of the aryl group include a phenyl group. Examples of the substituent of the aryl group include a halogen atom, a cyano group, a nitro group, and an alkyl group.

[0042] a and b may be the same or different, and each is an integer of 1 to 3, and c is an integer of 0 to 2, provided that a+b+c=4. a=1, b=3, and c=0, and a=1, b=2, and c=1 are preferred, and a=1, b=3, and c=0 are more preferred.

[0043] The organosilicon compound is preferably a compound containing one or more carbon-carbon unsaturated bonds and one or more trialkoxysilyl groups. The number of carbon-carbon unsaturated bonds in the organosilicon compound is preferably 1 to 3, more preferably 1 to 2, and even more preferably 1. The number of trialkoxysilyl groups in the organosilicon compound is preferably 1 to 3, more preferably 1 to 2, and even more preferably 1.

[0044] The trialkoxysilyl group is -Si(R 11 ) 3 In the formula, the three R 11 are each independently an alkoxy group. The alkoxy group preferably has 1 to 10 carbon atoms, more preferably 1 to 6 carbon atoms, and further preferably 1 to 3 carbon atoms.

[0045] As the organosilicon compound, for example, a compound represented by the formula (E2) is preferable. X 1 -Y 1 -Si(R 11 ) 3 (E2) In formula (E2), X 1 is X in formula (E1). 1 is synonymous with Y 1 is Y in formula (E1). 1 There are three R 11 are each independently an alkoxy group. The alkoxy group preferably has 1 to 10 carbon atoms, more preferably 1 to 6 carbon atoms, and further preferably 1 to 3 carbon atoms.

[0046] The organosilicon compound preferably has 2-20 carbon atoms.

[0047] Examples of the compound represented by formula (E2) include alkenyltrialkoxysilane, (meth)acryloxyalkyltrialkoxysilane, (vinylphenyl)trialkoxysilane, and (vinylphenylalkyl)trialkoxysilane. Examples of alkenyltrialkoxysilanes include vinyltrialkoxysilanes such as vinyltrimethoxysilane, vinyltriethoxysilane, vinyltri-n-propoxysilane, vinyltriisopropoxysilane, vinyltri-n-butoxysilane, vinyltriisobutoxysilane, vinyltri-sec-butoxysilane, and vinyltri-tert-butoxysilane; allyltrialkoxysilanes such as allyltrimethoxysilane and allyltriethoxysilane; and octenyltrialkoxysilanes such as 7-octenyltrimethoxysilane and 7-octenyltriethoxysilane. Examples of (meth)acryloxyalkyltrialkoxysilanes include 3-(meth)acryloxypropyltrimethoxysilane, 3-(meth)acryloxypropyltriethoxysilane, 8-(meth)acryloxyoctyltrimethoxysilane, and 8-(meth)acryloxyoctyltriethoxysilane. Examples of (vinylphenyl)trialkoxysilanes include 4-vinylphenyltrimethoxysilane and 4-vinylphenyltriethoxysilane. Examples of (vinylphenylalkyl)trialkoxysilanes include 4-vinylphenyloctyltrimethoxysilane and 4-vinylphenyloctyltriethoxysilane.

[0048] Other examples of the compound represented by formula (E1) include alkenylalkyldialkoxysilanes, ((meth)acryloxyalkyl)alkyldialkoxysilanes, ((meth)acryloxyalkyl)aryldialkoxysilanes, vinylphenyldialkoxysilanes, allylphenyldialkoxysilanes, 4-vinylphenylalkyldialkoxysilanes, 4-vinylphenylphenyldialkoxysilanes, alkoxydialkylvinylsilanes, tris(alkoxyalkoxy)vinylsilanes, vinyltriacetoxysilanes, allyltriacetoxysilanes, (meth)acryloxyalkyltriacetoxysilanes, 4-vinylphenyltriacetoxysilanes, vinylalkyldiacetoxysilanes, vinylphenyldiacetoxysilanes, allylalkyldiacetoxysilanes, allylphenyldiacetoxysilanes, ((meth)acryloxyalkyl)alkyldiacetoxysilanes, ((meth)acryloxyalkyl)phenyldiacetoxysilanes, 4-vinylphenylalkyldiacetoxysilanes, and 4-vinylphenylphenyldiacetoxysilane. Examples of alkenylalkyldialkoxysilanes include dialkoxyalkylvinylsilanes such as dimethoxymethylvinylsilane and diethoxymethylvinylsilane; allylalkyldialkoxysilanes such as allylmethyldimethoxysilane and allylmethyldiethoxysilane; and octenylalkyldialkoxysilanes such as 7-octenylmethyldimethoxysilane and 7-octenylmethyldiethoxysilane. Examples of ((meth)acryloxyalkyl)alkyldialkoxysilanes include (3-(meth)acryloxypropyl)methyldimethoxysilane, (3-(meth)acryloxypropyl)methyldiethoxysilane, (3-(meth)acryloxypropyl)ethyldiethoxysilane, (8-(meth)acryloxyoctyl)methyldimethoxysilane, and (8-(meth)acryloxyoctyl)methyldiethoxysilane. Examples of ((meth)acryloxyalkyl)aryldialkoxysilanes include (3-(meth)acryloxypropyl)phenyldimethoxysilane and (3-(meth)acryloxypropyl)phenyldiethoxysilane.

[0049] The modified copolymer (B) may have one type of moiety derived from the above organosilicon compound, or may have two or more types of moieties derived from the above organosilicon compound.

[0050] By appropriately controlling the ethylene content and weight average molecular weight, the modified copolymer (B) becomes an amorphous copolymer with good fluidity, and the rubber composition tends to have good processability and flexibility. The modified copolymer (B) is a modified copolymer having a site derived from an organosilicon compound containing one or more carbon-carbon unsaturated bonds, and has excellent interaction and reactivity with the inorganic filler (C). In addition, the ethylene-α-olefin copolymer main chain of the modified copolymer (B) has a composition similar to that of the copolymer rubber (A), and the modified copolymer (B) has excellent compatibility with the copolymer rubber (A). For this reason, the modified copolymer (B) functions as a compatibilizer between the copolymer rubber (A) and the inorganic filler (C), the rubber composition has good dispersibility of the inorganic filler (C), and the obtained molded body tends to have excellent tensile properties such as tensile strength.

[0051] The rubber composition of the present disclosure may contain one type of modified copolymer (B) or may contain two or more types of modified copolymers (B). The content of the modified copolymer (B) in the rubber composition of the present disclosure is preferably 1 to 100 parts by mass, more preferably 5 to 50 parts by mass, further preferably 10 to 40 parts by mass, and particularly preferably 15 to 40 parts by mass, based on 100 parts by mass of the copolymer rubber (A). The rubber composition of such an embodiment tends to exhibit the above-mentioned effects more satisfactorily. In the manufacturing method of the rubber composition of the present disclosure, the above "content" is read as "blended amount". The same applies to other parts. The content of the modified copolymer (B) in the rubber composition of the present disclosure is preferably 20 to 200 parts by mass, more preferably 30 to 160 parts by mass, and further preferably 40 to 120 parts by mass, based on 100 parts by mass of the inorganic filler (C). The rubber composition of such an embodiment tends to exhibit the above-mentioned effects more satisfactorily.

[0052] <Method for producing modified copolymer (B)> The modified copolymer (B) can be produced, for example, by modifying an ethylene-α-olefin copolymer (B') having structural units derived from ethylene and structural units derived from an α-olefin having 3 or more carbon atoms as a base copolymer with the above-mentioned organosilicon compound. Specifically, the modified copolymer (B) can be produced by modifying the ethylene-α-olefin copolymer (B') by various conventionally known methods described in JP-A-61-126120 and Japanese Patent No. 2593264, or by the following method (1) or (2). Hereinafter, the ethylene-α-olefin copolymer (B') to be modified is also referred to as "copolymer (B')".

[0053] (1) A method in which copolymer (B') is charged into an extruder or a batch reactor, and the organosilicon compound to be reacted is added thereto to modify copolymer (B'). (2) A method in which the copolymer (B') is dissolved in a solvent and the organosilicon compound to be reacted is added thereto to modify the copolymer (B').

[0054] In either of the above methods, in order to efficiently react (preferably graft react) the copolymer (B') with the organosilicon compound, it is preferable to carry out the reaction in the presence of a radical initiator or the like.

[0055] The above organosilicon compounds may be used alone or in combination of two or more. The amount of the organosilicon compound used is preferably 0.5 to 150 parts by mass, more preferably 0.5 to 60 parts by mass, and even more preferably 0.5 to 40 parts by mass, based on 100 parts by mass of the copolymer (B').

[0056] Radical initiators include, for example, organic peroxides and azo compounds. Examples of organic peroxides include benzoyl peroxide, dichlorobenzoyl peroxide, dicumyl peroxide, di-t-butyl peroxide, 2,5-dimethyl-2,5-di(t-butylperoxy)hexane, 2,5-dimethyl-2,5-di(t-butylperoxy)-3-hexyne, 2,5-dimethyl-2,5-di(peroxybenzoate)-3-hexyne, 1,4-bis(t-butylperoxyisopropyl)benzene, t-butylperoxyacetate, t-butylperoxybenzoate, t-butylperoxyphenylacetate, t-butylperoxyisobutyrate, t-butylperoxy-sec-octoate, t-butylperoxypivalate, t-butylperoxydiethylacetate, and cumylperoxypivalate. As the organic peroxide, a compound having a decomposition temperature of 150 to 270°C with a half-life of 1 minute is preferable. Azo compounds include, for example, azobisisobutyronitrile and dimethylazoisobutyrate.

[0057] Among these, dialkyl peroxides such as dicumyl peroxide, di-t-butyl peroxide, 2,5-dimethyl-2,5-di(t-butylperoxy)hexane, 2,5-dimethyl-2,5-di(t-butylperoxy)-3-hexyne, and 1,4-bis(t-butylperoxyisopropyl)benzene are particularly preferred.

[0058] The radical initiator may be used alone or in combination of two or more. The amount of the radical initiator used is preferably 0.01 to 15 parts by mass, more preferably 0.05 to 10 parts by mass, and further preferably 0.1 to 8 parts by mass, based on 100 parts by mass of the copolymer (B').

[0059] The reaction temperature in the above modification reaction is preferably 20 to 350° C., more preferably 60 to 300° C., further preferably 120 to 200° C., and particularly preferably 130 to 180° C. The reaction time in the above modification reaction is preferably 30 minutes to 80 hours, and more preferably 1 hour to 50 hours.

[0060] The modified copolymer (B) is obtained, for example, by modifying (preferably graft-modifying) an ethylene-α-olefin copolymer (B') having structural units derived from ethylene and structural units derived from an α-olefin having 3 or more carbon atoms with the above-mentioned organosilicon compound. The copolymer (B') is, for example, a random copolymer of ethylene and an α-olefin having 3 or more carbon atoms. As described above, in the copolymer (B'), the content of structural units derived from ethylene is 10 to 90 mol%, preferably 30 to 80 mol%, more preferably 40 to 60 mol%. However, the total of the content of structural units derived from ethylene and the content of structural units derived from an α-olefin having 3 or more carbon atoms is 100 mol%.

[0061] The copolymer (B') may further have a structural unit derived from at least one other monomer selected from a polar group-containing monomer, an aromatic vinyl compound, and a cyclic olefin. The content of the structural unit derived from the other monomer in the copolymer (B') is preferably 20 moles or less, more preferably 10 moles or less, even more preferably 5 moles or less, even more preferably 1 mole or less, and particularly preferably 0.5 moles or less, per 100 moles in total of the structural unit derived from ethylene and the structural unit derived from an α-olefin having 3 or more carbon atoms. It is preferable that the copolymer (B') does not have a structural unit derived from the other monomer.

[0062] Examples of polar group-containing monomers include α,β-unsaturated carboxylic acids such as (meth)acrylic acid, fumaric acid, and maleic anhydride; metal salts of the α,β-unsaturated carboxylic acids, such as sodium salts; α,β-unsaturated carboxylic acid esters, such as methyl (meth)acrylate, ethyl (meth)acrylate, and n-propyl (meth)acrylate; vinyl esters, such as vinyl acetate and vinyl propionate; and unsaturated glycidyls, such as glycidyl (meth)acrylate.

[0063] Examples of aromatic vinyl compounds include styrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, o,p-dimethylstyrene, methoxystyrene, vinylbenzoic acid, methyl vinylbenzoate, vinylbenzyl acetate, hydroxystyrene, p-chlorostyrene, divinylbenzene, α-methylstyrene, and allylbenzene.

[0064] Examples of the cyclic olefin include cyclopentene, cycloheptene, norbornene, 5-methyl-2-norbornene, 5-ethylidene-2-norbornene, 5-vinyl-2-norbornene, and tetracyclododecene. The number of carbon atoms in the cyclic olefin is preferably 3 to 30, and more preferably 3 to 20.

[0065] As the method for producing copolymer (B'), for example, a method using a vanadium catalyst containing a vanadium compound and an organoaluminum compound, as described in JP-B-2-1163 or JP-B-2-7998, can be mentioned. As the method for producing copolymer (B') with high polymerization activity, for example, a method using a metallocene catalyst containing a metallocene compound such as zirconocene and an organoaluminum oxy compound (aluminoxane), as described in JP-A-61-221207, JP-B-7-121969, Japanese Patent No. 2796376 or JP-A-2015-147215, can be mentioned. This method is preferable from the viewpoint of reducing the chlorine content in the obtained copolymer and the 2,1-insertion amount of α-olefin.

[0066] The reduction in the 2,1-insertion amount of α-olefins makes it possible to further reduce the ethylene chains in the copolymer molecules, and since the intramolecular crystallinity of ethylene can be suppressed, the copolymer (B') tends to become an amorphous copolymer with good fluidity. Due to this characteristic, a rubber composition with good processability and flexibility can be obtained. The 2,1-insertion amount of α-olefins can be reduced according to the method described in JP-A-7-145212. 13 The amount of 2,1-insertion of α-olefin is preferably 1% or less, more preferably 0.5% or less, and further preferably 0.1% or less. 13 A copolymer in which no peak is observed in the range of 15.0 to 17.5 ppm in C-NMR measurement is particularly preferred.

[0067] For example, by using the following method, a copolymer (B') having a good balance of performance in terms of molecular weight, molecular weight distribution, amorphousness, etc. can be obtained. The copolymer (B') can be produced by copolymerizing ethylene and an α-olefin having 3 or more carbon atoms in the presence of an olefin polymerization catalyst. The olefin polymerization catalyst contains, for example, a bridged metallocene compound (P) represented by formula [I] and at least one compound (Q) selected from the group consisting of an organometallic compound (Q-1), an organoaluminum oxy compound (Q-2), and a compound (Q-3) that reacts with the bridged metallocene compound (P) to form an ion pair.

[0068] ((Bridged metallocene compound (P))) The bridged metallocene compound (P) is represented by the formula [I]. [ka]

[0069] Each element in formula [I] is explained below. R 1 , R 2 , R 3 , R 4 , R 5 , R8 , R 9 and R 12 R is each independently a hydrogen atom, a hydrocarbon group, or a silicon-containing hydrocarbon group. 1 , R 2 , R 3 , R 4 , R 5 , R 8 , R 9 and R 12 Adjacent groups in may be linked to each other to form a ring structure. R 6 and R 11 are the same group and are a hydrogen atom, a hydrocarbon group, or a silicon-containing hydrocarbon group. 7 and R 10 are the same group and are a hydrogen atom, a hydrocarbon group, or a silicon-containing hydrocarbon group. 6 and R 7 R may be bonded to a hydrocarbon having 2 to 3 carbon atoms to form a ring structure. 10 and R 11 R may be bonded to a hydrocarbon having 2 to 3 carbon atoms to form a ring structure. 6 , R 7 , R 10 and R 11 is not a hydrogen atom (i.e., R 6 =R 7 =R 10 =R 11 = never a hydrogen atom). R 13 and R 14 are each independently a hydrogen atom, a hydrocarbon group, or a silicon-containing hydrocarbon group, and may be linked together to form a ring structure.

[0070] Examples of the hydrocarbon group include hydrocarbon groups having 1 to 20 carbon atoms. Examples of the hydrocarbon group having 1 to 20 carbon atoms include linear saturated hydrocarbon groups having 1 to 20 carbon atoms, linear unsaturated hydrocarbon groups having 2 to 20 carbon atoms, cyclic saturated hydrocarbon groups having 3 to 20 carbon atoms, and cyclic unsaturated hydrocarbon groups having 3 to 20 carbon atoms.

[0071] Examples of the linear saturated hydrocarbon group having 1 to 20 carbon atoms include linear alkyl groups such as methyl, ethyl, n-propyl, n-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, n-nonyl, and n-decanyl; and branched alkyl groups such as isopropyl, isobutyl, s-butyl, t-butyl, t-amyl, neopentyl, 3-methylpentyl, 1,1-diethylpropyl, 1,1-dimethylbutyl, 1-methyl-1-propylbutyl, 1,1-propylbutyl, 1,1-dimethyl-2-methylpropyl, and 1-methyl-1-isopropyl-2-methylpropyl. The number of carbon atoms in the linear saturated hydrocarbon group is preferably 1 to 6.

[0072] Examples of the linear unsaturated hydrocarbon group having 2 to 20 carbon atoms include alkenyl groups such as ethenyl group (vinyl group), 1-propenyl group, 2-propenyl group (allyl group), and 1-methylethenyl group (isopropenyl group); and alkynyl groups such as ethynyl group, 1-propynyl group, and 2-propynyl group (propargyl group). The number of carbon atoms in the linear unsaturated hydrocarbon group is preferably 2 to 4.

[0073] Examples of cyclic saturated hydrocarbon groups having 3 to 20 carbon atoms include cyclic saturated hydrocarbon groups such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, norbornenyl, 1-adamantyl, and 2-adamantyl groups, and groups in which at least one hydrogen atom of the cyclic saturated hydrocarbon groups is replaced with a hydrocarbon group having 1 to 17 carbon atoms, such as 3-methylcyclopentyl, 3-methylcyclohexyl, 4-methylcyclohexyl, and 4-cyclohexylcyclohexyl. The number of carbon atoms in the cyclic saturated hydrocarbon group is preferably 5 to 11.

[0074] Examples of the cyclic unsaturated hydrocarbon group having 3 to 20 carbon atoms include cyclic unsaturated hydrocarbon groups such as phenyl group, naphthyl group, indenyl group, azulenyl group, phenanthryl group, anthracenyl group, cyclopentadienyl group, and norbornyl group; groups in which at least one hydrogen atom of the cyclic unsaturated hydrocarbon group is replaced with a hydrocarbon group having 1 to 15 carbon atoms, such as 3-methylphenyl group, 4-methylphenyl group, 4-ethylphenyl group, 4-t-butylphenyl group, 4-cyclohexylphenyl group, biphenylyl group, 3,4-dimethylphenyl group, 3,5-dimethylphenyl group, and 2,4,6-trimethylphenyl group; and groups in which at least one hydrogen atom of a chain saturated hydrocarbon group is replaced with a cyclic unsaturated hydrocarbon group having 3 to 19 carbon atoms, such as benzyl group and cumyl group. The number of carbon atoms of the cyclic unsaturated hydrocarbon group is preferably 6 to 10.

[0075] Examples of silicon-containing hydrocarbon groups include those in which at least one carbon atom in the above-mentioned hydrocarbon groups is replaced with a silicon atom, and specific examples thereof include alkylsilyl groups such as trimethylsilyl, triethylsilyl, t-butyldimethylsilyl, and triisopropylsilyl; arylsilyl groups such as dimethylphenylsilyl, methyldiphenylsilyl, and t-butyldiphenylsilyl; pentamethyldisilanyl, and trimethylsilylmethyl. 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.

[0076] R 13 and R 14 Preferably, one or both of R 13 and R 14 are both aryl groups, and R 2 and R 3 More preferably, either one of R is a saturated hydrocarbon group having 4 carbon atoms. 13 and R 14The bridged metallocene compound (P) in which both are aryl groups has high polymerization activity for copolymerization of ethylene and α-olefin, and the use of this bridged metallocene compound (P) selectively terminates polymerization by hydrogen introduction into the molecular end, so that the resulting copolymer (B') tends to have fewer unsaturated bonds. Therefore, by simply performing a simpler hydrogen addition operation or even without performing a hydrogen addition operation, it is possible to obtain a copolymer (B') with a high degree of saturation and excellent heat resistance, which tends to be excellent in terms of cost. In addition, the copolymer (B') obtained from the compound (P) tends to have a controlled molecular weight distribution due to its high random copolymerizability.

[0077] Y is a carbon atom or a silicon atom, preferably a carbon atom. M is a transition metal atom such as titanium (Ti), zirconium (Zr) or hafnium (Hf), and is preferably zirconium from the viewpoint of high polymerization activity.

[0078] Q is a halogen atom, a hydrocarbon group, an anionic ligand, or a neutral ligand capable of coordinating with a lone electron pair, and j is an integer of 1 to 4, preferably 2. When j is an integer of 2 or more, multiple Qs may be the same or different.

[0079] Examples of halogen atoms include fluorine, chlorine, bromine and iodine atoms. 1 etc. are as described above. When Q is a halogen atom, it is preferably a chlorine atom. When Q is a hydrocarbon group, it is preferably a hydrocarbon group having 1 to 7 carbon atoms.

[0080] Anionic ligands include, for example, alkoxy groups such as methoxy and t-butoxy groups; aryloxy groups such as phenoxy groups; carboxylate groups such as acetate and benzoate; and sulfonate groups such as mesylate and tosylate.

[0081] Examples of neutral ligands capable of coordinating with lone pairs of electrons include organic phosphorus compounds such as trimethylphosphine, triethylphosphine, triphenylphosphine, and diphenylmethylphosphine; and ether compounds such as tetrahydrofuran, diethyl ether, dioxane, and 1,2-dimethoxyethane.

[0082] Specific examples of the bridged metallocene compound (P) include the compounds listed in paragraphs

[0093] and

[0094] of JP-A-2023-51117.

[0083] The bridged metallocene compound (P) may be used alone or in combination of two or more.

[0084] ((Compound (Q))) The compound (Q) is at least one compound selected from the group consisting of an organometallic compound (Q-1), an organoaluminum oxy compound (Q-2), and a compound (Q-3) that reacts with the bridged metallocene compound (P) to form an ion pair. The compound (Q) may be used alone or in combination of two or more.

[0085] Examples of the organometallic compound (Q-1) include organometallic compounds (Q-1a), (Q-1b), and (Q-1c) of Groups 1, 2, 12, and 13 of the periodic table.

[0086] (Q-1a) General formula R a m Al(OR b ) n H p X q Organoaluminum compounds represented by. In the formula, R a and R b may be the same or different from each other, and are hydrocarbon groups having 1 to 15 carbon atoms, preferably 1 to 4 carbon atoms, X is a halogen atom, m is 0 < m ≦ 3, n is 0 ≦ n < 3, p is 0 ≦ p < 3, q is 0 ≦ q < 3, and m + n + p + q = 3.

[0087] Examples of such compounds include tri-n-alkylaluminums such as trimethylaluminum, triethylaluminum, tri-n-butylaluminum, tri-n-hexylaluminum, and tri-n-octylaluminum; tribranched alkylaluminums such as triisopropylaluminum, triisobutylaluminum, trisec-butylaluminum, tri-t-butylaluminum, tri-2-methylbutylaluminum, tri-3-methylhexylaluminum, and tri-2-ethylhexylaluminum; tricycloalkylaluminums such as tricyclohexylaluminum and tricyclooctylaluminum; triarylaluminums such as triphenylaluminum and tri(4-methylphenyl)aluminum; dialkylaluminum hydrides such as diisopropylaluminum hydride and diisobutylaluminum hydride; and compounds represented by the general formula (iC 4 H 9 ) x Al y (C 5 H 10 ) z (wherein x, y, and z are positive numbers, and z≦2x); alkylaluminum alkoxides such as isobutylaluminum methoxide and isobutylaluminum ethoxide; dialkylaluminum alkoxides such as dimethylaluminum methoxide, diethylaluminum ethoxide, and dibutylaluminum butoxide; alkylaluminum sesquialkoxides such as ethylaluminum sesquiethoxide and butylaluminum sesquibutoxide; a 2.5 Al(OR b ) 0.5and the like; alkylaluminum aryloxides such as diethylaluminum phenoxide and diethylaluminum (2,6-di-t-butyl-4-methylphenoxide); dialkylaluminum halides such as dimethylaluminum chloride, diethylaluminum chloride, dibutylaluminum chloride, diethylaluminum bromide, and diisobutylaluminum chloride; alkylaluminum sesquihalides such as ethylaluminum sesquichloride, butylaluminum sesquichloride, and ethylaluminum sesquibromide; partially halogenated alkylaluminums such as alkylaluminum dihalides such as ethylaluminum dichloride; dialkylaluminum hydrides such as diethylaluminum hydride and dibutylaluminum hydride; alkylaluminum dihydrides such as ethylaluminum dihydride and propylaluminum dihydride, and other partially hydrogenated alkylaluminums; partially alkoxylated and halogenated alkylaluminums such as ethylaluminum ethoxychloride, butylaluminum butoxychloride, and ethylaluminum ethoxybromide. Also, the above general formula R a m Al(OR b ) n H p X q Compounds similar to the compound represented by the formula (C) can also be used, such as organoaluminum compounds in which two or more aluminum compounds are bonded via nitrogen atoms. Examples of such compounds include organoaluminum compounds represented by the formula (C 2 H 5 ) 2 AlN(C 2 H 5 )Al(C 2 H 5 ) 2 Examples include:

[0088] (Q-1b) General formula M 2 AlR a 4It is a complex alkylation product of a metal in Group 1 of the periodic table and aluminum. In the formula, M 2 is Li, Na or K, and R a is a hydrocarbon group having 1 to 15 carbon atoms, preferably 1 to 4 carbon atoms.

[0089] Such compounds include, for example, LiAl(C 2 H 5 ) 4 , and LiAl(C 7 H 15 ) 4 Examples include:

[0090] (Q-1c) General formula R a R b M 3 A dialkyl compound of a metal in Group 2 or 12 of the periodic table, represented by the formula: In the formula, R a and R b may be the same or different and are hydrocarbon groups having 1 to 15 carbon atoms, preferably 1 to 4 carbon atoms; M 3 is Mg, Zn or Cd.

[0091] As the organoaluminum oxy compound (Q-2), a conventionally known aluminoxane can be used as it is. Specifically, the compounds represented by the general formula [II] and the compounds represented by the general formula [III] can be mentioned.

[0092] [ka] In the formulas [II] and [III], R is a hydrocarbon group having 1 to 10 carbon atoms, and n is an integer of 2 or more.

[0093] Methylaluminoxanes in which R is a methyl group and n is at least 3, preferably at least 10, are preferred. There is no problem if these aluminoxanes contain a small amount of an organoaluminum compound.

[0094] When copolymerization of ethylene with an α-olefin having 3 or more carbon atoms is carried out at high temperature, benzene-insoluble organoaluminum oxy compounds such as those exemplified in JP-A-2-78687 can also be used. In addition, organoaluminum oxy compounds described in JP-A-2-167305 and aluminoxanes having two or more alkyl groups described in JP-A-2-24701 and JP-A-3-103407 can also be suitably used. The term "benzene-insoluble organoaluminum oxy compounds" refers to compounds that are insoluble or poorly soluble in benzene, with the Al component dissolved in benzene at 60°C being preferably 10% or less, more preferably 5% or less, and even more preferably 2% or less in terms of Al atoms.

[0095] The organoaluminum oxy compound (Q-2) may, for example, be a modified methylaluminoxane represented by the general formula [IV].

[0096] [ka] In formula [IV], Rx is a hydrocarbon group having 1 to 10 carbon atoms, and m and n are each independently an integer of 2 or more.

[0097] The modified methylaluminoxane represented by formula [IV] is prepared using trimethylaluminum and alkylaluminum other than trimethylaluminum, for example, trimethylaluminum and triisobutylaluminum, as shown in U.S. Pat. Nos. 4,960,878 and 5,041,584. Aluminoxanes in which Rx is an isobutyl group are commercially available in the form of saturated hydrocarbon solutions under the trade names MMAO and TMAO (see Tosoh Finechem Corporation, Tosoh Research & Technology Review, Vol. 47, 55 (2003)).

[0098] The organoaluminum oxy compound (Q-2) also includes a boron-containing organoaluminum oxy compound represented by the general formula [V].

[0099] [ka] In formula [V], R c is a hydrocarbon group having 1 to 10 carbon atoms, R d may be the same or different and are a hydrogen atom, a halogen atom, or a hydrocarbon group having 1 to 10 carbon atoms.

[0100] Examples of the compound (Q-3) that reacts with the bridged metallocene compound (P) to form an ion pair (hereinafter also referred to as "ionized ionic compound" or simply "ionic compound") 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, JP-A-2004-51676 and U.S. Pat. No. 5,321,106, and further include heteropoly compounds and isopoly compounds.

[0101] An example of the ionized ionic compound is a boron compound represented by the general formula [VI].

[0102] [ka] In formula [VI], R e+ For example, H + , carbenium cations, oxonium cations, ammonium cations, phosphonium cations, cycloheptyltrienyl cations, and ferrocenium cations with transition metals. f ~R i may be the same or different and are substituents 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, and are preferably substituted aryl groups.

[0103] Examples of the carbenium cation include trisubstituted carbenium cations such as triphenylcarbenium cation, tris(4-methylphenyl)carbenium cation, and tris(3,5-dimethylphenyl)carbenium cation.

[0104] Examples of the ammonium cation include trialkyl-substituted ammonium cations such as trimethylammonium cation, triethylammonium cation, tri(n-propyl)ammonium cation, triisopropylammonium cation, tri(n-butyl)ammonium cation, and triisobutylammonium cation; N,N-dialkylanilinium cations such as N,N-dimethylanilinium cation, N,N-diethylanilinium cation, and N,N-2,4,6-pentamethylanilinium cation; and dialkylammonium cations such as diisopropylammonium cation and dicyclohexylammonium cation.

[0105] Examples of the phosphonium cation include triarylphosphonium cations such as triphenylphosphonium cation, tris(4-methylphenyl)phosphonium cation, and tris(3,5-dimethylphenyl)phosphonium cation.

[0106] R e+ Of the above specific examples, preferred are carbenium cations and ammonium cations, and more preferred are triphenylcarbenium cation, N,N-dimethylanilinium cation, and N,N-diethylanilinium cation.

[0107] Among the ionized ionic compounds, examples of compounds containing a carbenium cation include triphenylcarbenium tetraphenylborate, triphenylcarbenium tetrakis(pentafluorophenyl)borate, triphenylcarbenium tetrakis{3,5-di-(trifluoromethyl)phenyl}borate, tris(4-methylphenyl)carbenium tetrakis(pentafluorophenyl)borate, and tris(3,5-dimethylphenyl)carbenium tetrakis(pentafluorophenyl)borate.

[0108] Among the ionized ionic compounds, examples of compounds containing a trialkyl-substituted ammonium cation include triethylammonium tetraphenylborate, tripropylammonium tetraphenylborate, tri(n-butyl)ammonium tetraphenylborate, trimethylammonium tetrakis(4-methylphenyl)borate, trimethylammonium tetrakis(2-methylphenyl)borate, tri(n-butyl)ammonium tetrakis(pentafluorophenyl)borate, triethylammonium tetrakis(pentafluorophenyl)borate, tripropylammonium tetrakis(pentafluorophenyl)borate, tripropylammonium tetrakis(2,4-dimethylphenyl)borate, tri(n-butyl)ammonium tetrakis(3,5-dimethylphenyl)borate, and tri(n-butyl)ammonium tetrakis{4-(trifluoromethyl)phenyl}borate. ammonium tetrakis{3,5-di(trifluoromethyl)phenyl}borate, tri(n-butyl)ammonium tetrakis(2-methylphenyl)borate, dioctadecylmethylammonium tetraphenylborate, dioctadecylmethylammonium tetrakis(4-methylphenyl)borate, dioctadecylmethylammonium tetrakis(4-methylphenyl)borate, dioctadecylmethylammonium tetrakis(pentafluorophenyl)borate, dioctadecylmethylammonium tetrakis(2,4-dimethylphenyl)borate, dioctadecylmethylammonium tetrakis(3,5-dimethylphenyl)borate, dioctadecylmethylammonium tetrakis{4-(trifluoromethyl)phenyl}borate, and dioctadecylmethylammonium tetrakis{3,5-di(trifluoromethyl)phenyl}borate.

[0109] Among the ionized ionic compounds, examples of compounds containing an N,N-dialkylanilinium cation include N,N-dimethylanilinium tetraphenylborate, N,N-dimethylanilinium tetrakis(pentafluorophenyl)borate, N,N-dimethylanilinium tetrakis{3,5-di(trifluoromethyl)phenyl}borate, N,N-diethylanilinium tetraphenylborate, N,N-diethylanilinium tetrakis(pentafluorophenyl)borate, N,N-diethylanilinium tetrakis{3,5-di(trifluoromethyl)phenyl}borate, N,N-2,4,6-pentamethylanilinium tetraphenylborate, and N,N-2,4,6-pentamethylanilinium tetrakis(pentafluorophenyl)borate.

[0110] Among the ionizing ionic compounds, examples of compounds containing a dialkylammonium cation include di-n-propylammonium tetrakis(pentafluorophenyl)borate and dicyclohexylammonium tetraphenylborate.

[0111] Examples of catalyst system configurations include the following [1] to [4]. [1] Bridged metallocene compound (P) and compound (Q-2) [2] Includes bridged metallocene compound (P), compound (Q-1) and compound (Q-2) [3] Bridged metallocene compound (P), compound (Q-1) and compound (Q-3) are included. [4] Includes bridged metallocene compound (P), compound (Q-2) and compound (Q-3)

[0112] ((Carrier (R))) As a constituent component of the olefin polymerization catalyst, a support (R) may be used as necessary. The carrier (R) is an inorganic or organic compound, and is a granular or fine particle solid. Among these, the inorganic compound is preferably a porous oxide, an inorganic chloride, a clay, a clay mineral, or an ion-exchangeable layered compound. Specific examples of the carrier (R) include the compounds or substances listed in paragraphs

[0127] to

[0131] of JP 2023-51117 A.

[0113] The method of use and order of addition of each component of the polymerization catalyst can be selected arbitrarily. The bridged metallocene compound (P) and the compounds (Q-1) to (Q-3) can be introduced into the reaction system in any order. At least two or more of the components in the catalyst may be contacted in advance.

[0114] The bridged metallocene compound (P) (hereinafter also referred to as "component (P)") is, for example, preferably 10 -9 ~10 -1 moles, more preferably 10 -8 ~10 -2 It is used in molar amounts.

[0115] The organometallic compound (Q-1) (hereinafter also referred to as "component (Q-1)") is used in an amount such that the molar ratio of component (Q-1) to the transition metal atom (M) in component (P) [(Q-1) / M] is preferably 0.01 to 50,000, and more preferably 0.05 to 10,000.

[0116] The organoaluminum oxy compound (Q-2) (hereinafter also referred to as "component (Q-2)") is used in an amount such that the molar ratio [(Q-2) / M] of the aluminum atom in component (Q-2) to the transition metal atom (M) in component (P) is preferably 10 to 5,000, and more preferably 20 to 2,000.

[0117] The ionic compound (Q-3) (hereinafter also referred to as "component (Q-3)") is used in an amount such that the molar ratio of component (Q-3) to the transition metal atom (M) in component (P) [(Q-3) / M] is preferably 1 to 10,000, and more preferably 1 to 5,000.

[0118] The polymerization temperature is preferably −50 to 300° C., more preferably 30 to 250° C., further preferably 100 to 250° C., and particularly preferably 130 to 200° C. The polymerization pressure is preferably normal pressure to 10 MPa gauge pressure (MPa-G), more preferably normal pressure to 8 MPa-G.

[0119] The polymerization reaction can be carried out in any of batch, semi-continuous and continuous systems. Furthermore, the polymerization can be carried out continuously in two or more polymerization vessels with different reaction conditions.

[0120] The molecular weight of the resulting copolymer can be adjusted by changing the hydrogen concentration in the polymerization system and / or the polymerization temperature, and can also be adjusted by the amount of compound (Q) used. When hydrogen is added, the amount is preferably about 0.001 to 5,000 NL per kg of the resulting copolymer.

[0121] The polymerization solvent used in the liquid phase polymerization method is preferably an inert hydrocarbon solvent, more preferably a saturated hydrocarbon having a boiling point of 50 to 200°C under normal pressure. Specific examples of the polymerization solvent include aliphatic hydrocarbons such as propane, butane, pentane, hexane, heptane, octane, decane, dodecane, and kerosene; alicyclic hydrocarbons such as cyclopentane, cyclohexane, and methylcyclopentane, and particularly preferably hexane, heptane, octane, decane, and cyclohexane. The α-olefin itself to be polymerized can also be used as the polymerization solvent. Aromatic hydrocarbons such as benzene, toluene, and xylene, and halogenated hydrocarbons such as ethylene chloride, chlorobenzene, and dichloromethane can also be used as the polymerization solvent, but from the viewpoint of reducing the burden on the environment and minimizing the impact on human health, the use of these may not be preferable.

[0122] The molecular weight distribution (Mw / Mn) of the copolymer can be adjusted by removing low molecular weight components of the copolymer by a conventionally known method such as vacuum distillation. The copolymer obtained may be hydrogenated by a conventionally known method. If the double bonds of the copolymer obtained are reduced by hydrogenation, the oxidation stability and heat resistance are improved.

[0123] <Inorganic filler (C)> The rubber composition of the present disclosure contains an inorganic filler (C). The rubber composition containing the inorganic filler (C) tends to be capable of forming a molded article having excellent tensile properties such as tensile strength, and mechanical properties such as hardness and abrasion resistance.

[0124] Examples of the inorganic filler (C) include silicon-containing fillers such as silica, finely powdered silicic acid, talc, kaolinite, clay, and diatomaceous earth; oxide-based fillers such as alumina, magnesium oxide, barium oxide, and calcium oxide; hydroxide-based fillers such as aluminum hydroxide and magnesium hydroxide; calcium carbonate-based fillers such as light calcium carbonate and heavy calcium carbonate; carbon-based fillers such as carbon black and graphite; magnetic fillers such as ferrite, iron, and cobalt; conductive fillers such as silver, gold, copper, and alloys; limestone, etc. Among these, from the viewpoint of the interaction or reactivity between the inorganic filler (C) and the modified copolymer (B), silicon-containing fillers are preferred, silanol group-containing fillers are more preferred, and silica is even more preferred.

[0125] In particular, it is preferred that the modified copolymer (B) is a modified copolymer having a site derived from a compound having one or more carbon-carbon unsaturated bonds and one or more hydrolyzable groups directly bonded to silicon, and the inorganic filler (C) is a silanol group-containing filler. This is because, in such a combination, for example, the Si-OH groups on the surface of the silanol group-containing filler react well with the Si-hydrolyzable groups in the modified copolymer to form siloxane bonds (-Si-O-Si-), and the modified copolymer is unevenly distributed on the surface of the filler, thereby more effectively exerting the above-mentioned effects.

[0126] Examples of silica include dry silica (anhydrous silicic acid) and wet silica (hydrated silicic acid). Among these, wet silica is preferred because it has a large number of silanol groups. Examples of wet silica include precipitated silica and gel silica, with precipitated silica being preferred. Silica may be surface-treated with, for example, reactive silane or low molecular weight siloxane. Examples of reactive silane include hexamethyldisilazane, chlorosilane, and alkoxysilane.

[0127] The nitrogen adsorption specific surface area of ​​silica (N 2 SA) is preferably 50 to 500 m 2 / g, more preferably 150 to 400m 2 / g. The N of silica 2 SA is measured by a method in accordance with ASTM D3037-81.

[0128] The rubber composition of the present disclosure may contain one type of inorganic filler (C), or may contain two or more types of inorganic fillers (C). The content of the inorganic filler (C) in the rubber composition of the present disclosure is preferably 1 to 200 parts by mass, more preferably 5 to 100 parts by mass, and further preferably 10 to 80 parts by mass, based on 100 parts by mass of the copolymer rubber (A). The rubber composition of such an embodiment tends to be capable of forming a molded article having excellent mechanical properties.

[0129] <Coupling agent (D)> The rubber composition of the present disclosure contains a coupling agent (D). The coupling agent is preferably an organic silane coupling agent.The organic silane coupling agent can be, for example, a sulfide-functional silane coupling agent, a mercapto-functional silane coupling agent, an alkenyl-functional silane coupling agent, a (meth)acrylic-functional silane coupling agent, an epoxy-functional silane coupling agent, and an amino- or imino-functional silane coupling agent.

[0130] Examples of sulfide-functional silane coupling agents include bis(2-trimethoxysilylethyl)tetrasulfide, bis(2-triethoxysilylethyl)tetrasulfide, bis(3-trimethoxysilylpropyl)tetrasulfide, bis(3-triethoxysilylpropyl)tetrasulfide, bis(3-diethoxymethylsilylpropyl)tetrasulfide, bis(2-trimethoxysilylethyl)disulfide, bis(2-triethoxysilylethyl)disulfide, bis(3-trimethoxysilylpropyl)disulfide, bis(3-triethoxysilylpropyl)disulfide, and bis(3-diethoxymethylsilylpropyl)disulfide.

[0131] Examples of mercapto-functional silane coupling agents include 2-mercaptoethyltrimethoxysilane, 2-mercaptoethyltriethoxysilane, 2-mercaptoethylmethyldimethoxysilane, 2-mercaptoethylmethyldiethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, 3-mercaptopropylmethyldimethoxysilane, and 3-mercaptopropylmethyldiethoxysilane.

[0132] Alkenyl-functional silane coupling agents include, for example, vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris(2-methoxyethoxy)silane, vinylmethyldimethoxysilane, vinylmethyldiethoxysilane, propenyltrimethoxysilane, and propenyltriethoxysilane.

[0133] Examples of (meth)acryloxy-functional silane coupling agents include (meth)acryloxymethyltrimethoxysilane, (meth)acryloxymethyltriethoxysilane, 3-(meth)acryloxypropyltrimethoxysilane, 3-(meth)acryloxypropyltriethoxysilane, 3-(meth)acryloxypropylmethyldimethoxysilane, and 3-(meth)acryloxypropylmethyldiethoxysilane.

[0134] Epoxy-functional silane coupling agents include, for example, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltriethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, and 3-glycidoxypropylmethyldiethoxysilane.

[0135] Amino- or imino-functional silane coupling agents include, for example, alkoxysilanes containing amino groups and / or imino groups, such as 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, N-(2-aminoethyl)-3-aminopropyltriethoxysilane, N-(2-aminoethyl)-3-aminopropylmethyldimethoxysilane, N-(2-aminoethyl)-3-aminopropylmethyldiethoxysilane, N,N'-bis(3-(trimethoxysilyl)propyl)ethylenediamine, and N,N'-bis(3-(triethoxysilyl)propyl)ethylenediamine; Reaction products of amino- and / or imino-containing alkoxysilanes with epoxy-functional silane coupling agents such as 3-glycidoxypropyltrimethoxysilane, and 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane; Reaction products of amino- and / or imino-containing alkoxysilanes with (meth)acryl-functional silane coupling agents, such as (meth)acryloxymethyltrimethoxysilane, and 3-(meth)acryloxypropyltrimethoxysilane; Examples include:

[0136] The molecular weight of the coupling agent (D) is, for example, less than 1,000.

[0137] The rubber composition of the present disclosure may contain one type of coupling agent (D) or may contain two or more types of coupling agents (D). The content ratio of the coupling agent (D) in the rubber composition of the present disclosure is preferably 0.5 to 20 mass%, more preferably 1 to 17 mass%, and further preferably 1.5 to 15 mass% in the total of 100 mass% of the inorganic filler (C) and the coupling agent (D). The rubber composition of such an embodiment tends to be capable of forming a molded article having an excellent balance between tensile properties and mechanical properties. In the manufacturing method of the rubber composition of the present disclosure, the above "content ratio" is read as "blending ratio".

[0138] <Other ingredients> The rubber composition of the present disclosure may contain other components in addition to the above-mentioned components (A) to (D). Examples of the other components include rubber components other than the copolymer rubber (A), plastics, crosslinking agents, crosslinking assistants, softeners, plasticizers, tackifiers, colorants, foaming agents, foaming assistants, activators, reaction inhibitors, dispersants, flame retardants, lubricants, ultraviolet absorbers, heat stabilizers, antioxidants, and antiaging agents. The rubber composition of the present disclosure may contain one type of other component, or may contain two or more types of other components.

[0139] Examples of rubber components other than the copolymer rubber (A) include natural rubber, isoprene rubber, butyl rubber, halogenated butyl rubber, butadiene rubber, styrene-butadiene rubber, acrylonitrile-butadiene rubber, nitrile rubber, acrylic rubber, chloroprene rubber, fluororubber, urethane rubber, and silicone rubber. Plastics include, for example, polyolefins such as crystalline polypropylene and poly(4-methyl-1-pentene), nylon, polyester, and polycarbonate.

[0140] Examples of crosslinking agents include organic peroxides; sulfur such as powdered sulfur, precipitated sulfur, colloidal sulfur, surface-treated sulfur, and insoluble sulfur; sulfur compounds such as sulfur monochloride, sulfur dichloride, morpholine disulfide, alkylphenol disulfide, tetramethylthiuram disulfide, dipentamethylenethiuram tetrasulfide, and selenium dimethyldithiocarbamate; and metal compounds such as magnesium oxide, zinc oxide, and red lead.

[0141] Examples of organic peroxides include dicumyl peroxide, di-t-butyl peroxide, di-t-butylperoxy-3,3,5-trimethylcyclohexane, t-butylcumyl peroxide, di-t-amyl peroxide, t-butyl hydroperoxide, 2,5-dimethyl-2,5-di(t-butylperoxy)hexyne-3, 2,5-dimethyl-2,5-di(benzoylperoxy)hexane, 2,5-dimethyl-2,5-mono(t-butylperoxy)hexane, and and α,α'-bis(t-butylperoxy-m-isopropyl)benzene; peroxy esters such as t-butyl peroxyacetate, t-butyl peroxyisobutyrate, t-butyl peroxypivalate, t-butyl peroxymaleic acid, t-butyl peroxyneodecanoate, t-butyl peroxybenzoate, and di-t-butyl peroxyphthalate; and ketone peroxides such as dicyclohexanone peroxide.

[0142] As the form of the organic peroxide, it is possible to use the organic peroxide as it is, but due to the problem of handling, it is preferable to use a diluted product in which the organic peroxide is adsorbed on an inorganic filler such as calcium carbonate, or a master batch type diluted product for the purpose of suppressing powdering during kneading and improving dispersibility in a polymer. The concentration of the organic peroxide in the diluted product is preferably 10 to 60% by mass, more preferably 20 to 50% by mass.

[0143] When the rubber composition of the present disclosure contains an organic peroxide, the content of the organic peroxide is preferably 0.05 to 10 parts by mass, more preferably 0.1 to 5 parts by mass, per 100 parts by mass of the total of the copolymer rubber (A) and the modified copolymer (B).

[0144] When the rubber composition of the present disclosure contains sulfur or a sulfur compound, the content of the sulfur or the sulfur compound is preferably 0.05 to 10 parts by mass, more preferably 0.1 to 5 parts by mass, per 100 parts by mass of the total of the copolymer rubber (A) and the modified copolymer (B).

[0145] When an organic peroxide is used as the crosslinking agent, examples of the crosslinking assistant include sulfur, sulfur compounds such as dipentamethylene thiuram tetrasulfide, quinone dioxime compounds such as p-quinone dioxime and p,p'-dibenzoyl quinone oxime, and polyfunctional monomers. Examples of the polyfunctional monomer include (meth)acrylate compounds such as polyethylene glycol di(meth)acrylate, allyl compounds such as diallyl phthalate and triallyl cyanurate, maleimide compounds such as metaphenylene bismaleimide and toluylene bismaleimide, and divinylbenzene.

[0146] When sulfur or a sulfur compound is used as the crosslinking agent, examples of the crosslinking assistant include sulfenamide compounds such as N-cyclohexyl-2-benzothiazole sulfenamide, N-oxydiethylene-2-benzothiazole sulfenamide, Nt-butyl-2-benzothiazole sulfenamide, and N,N-diisopropyl-2-benzothiazole sulfenamide; 2-mercaptobenzothiazole, 2-(2,4-dinitrophenyl)mercaptobenzothiazole, 2-(4-morpholino)-2-phenylpropanediol, and the like. Thiazole compounds such as 2-(2,6-diethyl-4-morpholinothio)benzothiazole, 2-(2,6-diethyl-4-morpholinothio)benzothiazole, and dibenzothiazyl disulfide; guanidine compounds such as diphenylguanidine, triphenylguanidine, diorthotolylguanidine, orthotolylbiguanide, and diphenylguanidine phthalate; aldehyde amines such as acetaldehyde-aniline condensation product, butyraldehyde-aniline condensation product, hexamethylenetetramine, and acetaldehyde ammonia; or aldehyde-ammonia compounds; imidazoline compounds such as 2-mercaptoimidazoline; thiourea compounds such as thiocarbanilide, diethylthiourea, dibutylthiourea, trimethylthiourea, and diorthotolylthiourea; tetramethylthiuram monosulfide, tetramethylthiuram disulfide, tetraethylthiuram disulfide, tetrabutylthiuram disulfide, tetrakis(2-ethylhexyl)thiuram disulfide, and dipentamethylenethiuram tetrasulfide. dithiocarbamates such as zinc dimethyldithiocarbamate, zinc diethyldithiocarbamate, zinc di-n-butyldithiocarbamate, zinc ethylphenyldithiocarbamate, zinc butylphenyldithiocarbamate, sodium dimethyldithiocarbamate, selenium dimethyldithiocarbamate, and tellurium dimethyldithiocarbamate; xanthates such as zinc dibutylxanthate; zinc oxide (zinc oxide); and fatty acids such as stearic acid.

[0147] When the rubber composition of the present disclosure contains a crosslinking aid, the content of the crosslinking aid is preferably 0.1 to 20 parts by mass, more preferably 0.2 to 10 parts by mass, per 100 parts by mass of the total of the copolymer rubber (A) and the modified copolymer (B).

[0148] The modified copolymer (B) can also exert its effect as a softener, but a softener other than the modified copolymer (B) may also be used. Examples of such softeners include petroleum-based softeners such as mineral oil, lubricating oil, paraffin, liquid paraffin, petroleum asphalt, and vaseline; coal tar-based softeners such as coal tar and coal tar pitch; fatty oil-based softeners such as castor oil, linseed oil, rapeseed oil, soybean oil, and coconut oil; tall oil; sap; waxes such as beeswax, carnauba wax, and lanolin; fatty acids and their salts such as ricinoleic acid, palmitic acid, stearic acid, barium stearate, calcium stearate, and zinc laurate; synthetic polymer substances such as petroleum resin, atactic polypropylene, and coumarone-indene resin. Among these, petroleum-based softeners are preferred, and mineral oil is more preferred.

[0149] When the rubber composition of the present disclosure contains a softener other than the modified copolymer (B), the content of the softener is preferably 1 to 100 parts by mass, more preferably 2 to 80 parts by mass, per 100 parts by mass of the copolymer rubber (A).

[0150] Examples of the plasticizer include phthalate, adipate, sebacate, or phosphate plasticizers. Examples of the tackifier include coumarone-indene resin, terpene-phenol resin, and xylene-formaldehyde resin. Examples of the colorant include inorganic pigments and organic pigments. Examples of the foaming agent include sodium bicarbonate, ammonium carbonate, N,N'-dinitrosopentamethylenetetramine, azocarbonamide, azobisisobutyronitrile, benzenesulfonyl hydrazide, toluenesulfonyl hydrazide, calcium amide, and paratoluenesulfonyl azide. Examples of the foaming assistant include salicylic acid, phthalic acid, and urea.

[0151] <Production of Rubber Composition> The rubber composition of the present disclosure can be produced, for example, by blending the copolymer rubber (A), the modified ethylene-α-olefin copolymer (B), the inorganic filler (C) and the coupling agent (D), and other components as necessary, by a known method.

[0152] The production of the rubber composition and the production of a molded body, a premolded body for producing a cross-linked molded body, or a cross-linked molded body may be carried out continuously, or after the rubber composition is produced, molding and cross-linking may be carried out separately using the rubber composition.

[0153] When producing a crosslinked molded article from a rubber composition, for example, an uncrosslinked rubber composition (compounded rubber) may be produced once, as in the case of crosslinking general rubber, and then this compounded rubber may be molded into an intended shape and then crosslinked.

[0154] Specifically, the rubber composition can be produced by the following method: Using an internal mixer (internal mixer) such as a Banbury mixer, kneader or intermix, the copolymer rubber (A), the modified ethylene-α-olefin copolymer (B), the inorganic filler (C), the coupling agent (D), and other components as required are kneaded at a temperature of 90 to 170°C for 1 to 20 minutes, and then using rolls such as an open roll or a kneader, other components (crosslinking agent, crosslinking aid, foaming agent, etc.) are added and mixed as required, and the mixture is kneaded at 40 to 90°C for 5 to 30 minutes and then separated to produce the rubber composition.

[0155] The crosslinkable rubber composition produced as described above can be molded into an intended shape by various molding methods using an extrusion molding machine, a calendar roll, a press molding machine, an injection molding machine, a transfer molding machine, or the like, and crosslinked either simultaneously with molding or by introducing the obtained molded body into a crosslinking tank.

[0156] The crosslinking can be carried out by heating at preferably 100 to 270°C, more preferably 110 to 250°C, and even more preferably 120 to 200°C, for preferably 1 to 60 minutes, more preferably 5 to 40 minutes, and even more preferably 10 to 30 minutes. When obtaining a crosslinked molded product by crosslinking with heat in this way, it is preferable that the rubber composition contains a crosslinking agent. Crosslinking can also be carried out by irradiating a predetermined amount of radiation to a molded uncrosslinked rubber composition as necessary. Examples of radiation include α-rays, β-rays, γ-rays, electron beams, neutron beams, and X-rays. When crosslinking is carried out by irradiation with radiation such as electron beams, the rubber composition does not necessarily need to contain a crosslinking agent. Crosslinking may be carried out using a mold, or may be carried out without using a mold. When a mold is not used, the molding and crosslinking steps are usually carried out continuously. For heating in the crosslinking tank, for example, hot air, steam, a glass bead fluidized bed, UHF (ultra-high frequency electromagnetic wave), or LCM (thermal molten salt bath) can be used.

[0157] [Application] The rubber composition of the present disclosure or a molded article thereof can be applied to products used in the fields of, for example, moving objects (e.g., automobiles, ships, aircraft, or railway vehicles, and related products thereof), construction and civil engineering, medical care, electrical and electronic equipment, machinery, food and cosmetics, textiles, and pulp. A molded article according to the present disclosure includes the rubber composition or a crosslinked product thereof.

[0158] Examples of automotive related products include the following: (1) Tire parts such as the tread, carcass, sidewall, inner liner, undertread, and belt section, (2) Exterior parts such as radiator grilles, side moldings, garnishes (pillars, rear, cowl tops), aero parts (air dams, spoilers), wheel covers, weather strips, cowbelt grilles, air outlet louvers, air scoops, hood bulges, ventilation parts, anti-touch parts (over fenders, side seal panels, moldings (windows, hoods, door belts)), and marks; weather strip sponges for doors, lights, and wipers (for example, door weather strips, trunk weather strips, luggage weather strips, roof side rail weather strips, sliding door weather strips, ventilator weather strips, sliding roof weather strips, front window weather strips, rear window weather strips, quarter window weather strips, rock pillar weather strips, door glass outer weather strips, door glass inner weather strips), glass runs, glass run channels, and other interior window frame parts; (3) Air duct hoses, radiator hoses, brake hoses, (4) Lubricating oil parts such as crankshaft seals, valve stem seals, head cover gaskets, A / T oil cooler hoses, transmission oil seals, P / S hoses, and P / S oil seals, (5) Fuel system parts such as fuel hoses, emission control hoses, inlet filler hoses, and diaphragms; vibration-proof parts such as engine mounts and in-tank pump mounts; (6) Boots such as CVJ boots, rack and pinion boots, (7) Air conditioning parts such as A / C hoses and A / C seals, (8) Timing belts, auxiliary belts, and other belt parts, (9) Sealers, such as windshield sealers, vinyl plastisol sealers, anaerobic sealers, body sealers, and spot weld sealers.

[0159] Examples of construction and civil engineering products include building material sealants used for butt joints in glass screen construction in commercial buildings, joints around glass between sashes, interior joints in toilets, washrooms or showcases, joints around bathtubs, exterior expansion joints for prefabricated houses, and joints for sizing boards; sealing materials for double-glazing; civil engineering sealants used in road repairs; paints and adhesives for metal, glass, stone, slate, concrete or roof tiles; adhesive sheets, waterproof sheets, and vibration-proof sheets.

[0160] Examples of medical products include rubber stoppers for medicines, syringe gaskets, and rubber stoppers for reduced pressure blood vessels.

[0161] Examples of products for electrical and electronic equipment include sealing materials, potting materials, coating materials or adhesives for heavy electrical parts, low electrical parts, and circuits and substrates of electrical and electronic equipment; sealing materials for wiring connection branch boxes, electrical system parts or electric wires; adhesives for electric wires or glass; repair materials for electric wire coatings; insulating sealing materials for electric wire joint parts; rolls for office equipment (charging rolls, transfer rolls, developing rolls, paper feed rolls); vibration absorbers; grommets; and encapsulating materials for gels or capacitors.

[0162] Applications of the rubber composition of the present invention or its molded article partially overlap with those mentioned above, but further include belts, hoses, tubes, sheets, sealing materials, potting materials, coating materials, adhesives, and vibration damping materials.

[0163] Examples of belts include power transmission belts (V-belts, flat belts, toothed belts, timing belts), and conveyor belts (light conveyor belts, cylindrical belts, rough top belts, flanged conveyor belts, U-shaped guided conveyor belts, V-shaped guided conveyor belts). Examples of hoses include radiator hoses and heater hoses. Examples of tubes include vacuum tubes and tire tubes. Examples of sheets include roofing sheets, waterproof sheets, and rubber sheets.

[0164] Examples of the sealing material include sealing materials for refrigerators, freezers, washing machines, gas meters, microwave ovens, steam irons, and earth leakage breakers. Materials used for the purpose of making joints and contacts watertight or airtight in various industries such as mechanical, electrical, and chemical industries are also sealing materials in a broad sense.

[0165] Examples of potting materials include potting materials for potting high-voltage transformer circuits, printed circuit boards, high-voltage transformers with variable resistors, electrical insulating parts, semiconductive parts, conductive parts, solar cells, or flyback transformers for televisions.

[0166] Examples of coating materials include coating materials for coating various circuit elements such as high-voltage thick film resistors or hybrid ICs; HICs, electrically insulating components; semiconductive components; conductive components; modules; printed circuits; ceramic substrates; buffer materials such as diodes, transistors, or bonding wires; semiconductive elements; or optical fibers for optical communications.

[0167] Adhesives include, for example, adhesives for bonding cathode ray tube wedges, necks, electrically insulating parts, semiconducting parts, or conductive parts.

[0168] Examples of vibration-damping materials include vibration-proof rubbers, such as automobile vibration-proof rubbers (engine mounts, liquid-sealed engine mounts, damper pulleys, chain dampers, carburetor mounts, torsional dampers, strut mounts, rubber bushes, bumper rubbers, helper rubbers, spring seats, shock absorbers, air springs, body mounts, bumper guards, muffler supports, rubber couplings, center bearing supports, clutch rubbers, differential mounts, suspension bushes, sliding bushes, cushion strut bars, stoppers, handle dampers, radiator supporters, or muffler hangers), railway vibration-proof rubbers (slab mats, ballast mats, or track mats), and industrial machine vibration-proof rubbers (expansion joints, flexible joints, bushes, and mounts).

[0169] Applications of the rubber composition or a molded article thereof according to the present disclosure partially overlap with those described above, but further include automotive cups and seals (master cylinder piston cups, wheel cylinder piston cups, constant velocity joint boots, pin boots, dust covers, piston seals, packings, O-rings, diaphragms, dam windshields, door mirror brackets, sealed headlamps, sealed cowl tops), industrial seals (capacitor packings, O-rings, packings), foams (hose protection sponges, cushion sponges, heat insulating sponges, insulation pipes), coated electric wires, electric wire joints, electrical insulating parts, semiconductive rubber parts, industrial rolls (ironmaking rolls, papermaking rolls, printing electric wire rolls), anode caps, plug caps, ignition cables, lamp socket covers, terminal covers, wiper blades, air springs, shoe soles, shoe heels, tire sidewalls, and fabric coatings.

[0170] Applications of the rubber composition or molded article thereof according to the present disclosure partially overlap with the applications described above, but further include air conditioning-related products such as passenger vehicle air conditioners, bus air conditioners, and freezers, rollers, linings, rubber-coated cloth, gloves, fenders, medical rubber (syringe gaskets, tubes, catheters), gaskets (for home appliances and construction), leisure products (swimming components such as swimming caps, diving masks, and earplugs; gel cushioning components such as sports shoes and baseball gloves), asphalt modifiers, hot melt adhesives, boots, and grips. , toys, shoes, sandals, keypads, gear, elastomers such as PET bottle cap liners, rubber footwear, rubber rolls, printing blankets, rubber and resin linings, conductive rubber products, urethane coating waterproofing, sealing devices, extruded rubber products, sponge rubber products, fenders, construction gaskets, seismic isolation rubber, rubber blocks for paving, non-metallic chains, medical and sanitary rubber products, rubber-coated fabric products, rubber and vinyl gloves, coating materials such as anti-fingerprint coatings for touch panels, lubricating coats for metal surfaces, and primers for metal painting.

[0171] [Example of the situation] The present disclosure relates to, for example, the following [1] to

[15] . [1] A rubber composition comprising one or more copolymer rubbers (A) selected from ethylene-α-olefin copolymer rubbers and ethylene-α-olefin-non-conjugated polyene copolymer rubbers, a modified ethylene-α-olefin copolymer (B) satisfying the following requirements (b-1) to (b-3), an inorganic filler (C), and a coupling agent (D), wherein, relative to 100 parts by mass of the copolymer rubber (A), the content of the modified ethylene-α-olefin copolymer (B) is 1 to 100 parts by mass, the content of the inorganic filler (C) is 1 to 200 parts by mass, and the content of the coupling agent (D) is 0.5 to 20% by mass relative to 100 parts by mass of the total of the inorganic filler (C) and the coupling agent (D); Requirement (b-1): the content of structural units derived from ethylene in the ethylene-α-olefin copolymer (B') before modification is 10 to 90 mol % (wherein the total of the content of structural units derived from ethylene and the content of structural units derived from an α-olefin having 3 or more carbon atoms is 100 mol %); Requirement (b-2): the weight average molecular weight (Mw) determined by gel permeation chromatography (GPC) is 1,000 to 100,000; Requirement (b-3): The modified ethylene-α-olefin copolymer (B) is a modified copolymer having a moiety derived from an organosilicon compound containing one or more carbon-carbon unsaturated bonds, and the content of the moiety derived from the organosilicon compound in 100% by mass of the modified copolymer is 0.5 to 50% by mass. [2] The rubber composition according to [1], wherein in the requirement (b-1), the content of structural units derived from ethylene is 40 to 60 mol %, in the requirement (b-2), the weight average molecular weight (Mw) determined by gel permeation chromatography (GPC) is 2,000 to 30,000, and in the requirement (b-3), the content of the moiety derived from the organosilicon compound in 100 mass % of the modified copolymer is 0.5 to 20 mass %. [3] The rubber composition according to the above [1] or [2], wherein the content of the modified ethylene-α-olefin copolymer (B) is 10 to 40 parts by mass, the content of the inorganic filler (C) is 10 to 80 parts by mass, and the content of the coupling agent (D) is 1.5 to 15 mass% in the total of 100 mass% of the inorganic filler (C) and the coupling agent (D). [4] The rubber composition according to any one of [1] to [3], wherein in the requirement (b-3), the organosilicon compound is a compound containing one or more carbon-carbon unsaturated bonds and one or more trialkoxysilyl groups, and the inorganic filler (C) is a silicon-containing filler. [5] A belt comprising the rubber composition or a crosslinked product thereof according to any one of the above [1] to [4]. [6] A hose comprising the rubber composition or a crosslinked product thereof according to any one of the above [1] to [4]. [7] A tube comprising the rubber composition or a crosslinked product thereof according to any one of the above [1] to [4]. [8] A sealing material comprising the rubber composition or a crosslinked product thereof according to any one of the above [1] to [4]. [9] A vibration damping material comprising the rubber composition or a crosslinked product thereof according to any one of the above [1] to [4].

[10] A method for producing a rubber composition, comprising the step of mixing one or more copolymer rubbers (A) selected from ethylene-α-olefin copolymer rubbers and ethylene-α-olefin-non-conjugated polyene copolymer rubbers, a modified ethylene-α-olefin copolymer (B) satisfying the following requirements (b-1) to (b-3), an inorganic filler (C), and a coupling agent (D), wherein, in the step, the amount of the modified ethylene-α-olefin copolymer (B) is 1 to 100 parts by mass, the amount of the inorganic filler (C) is 1 to 200 parts by mass, and the mixing ratio of the coupling agent (D) is 0.5 to 20 mass% relative to 100 parts by mass of the total of the inorganic filler (C) and the coupling agent (D); Requirement (b-1): the content of structural units derived from ethylene in the ethylene-α-olefin copolymer (B') before modification is 10 to 90 mol % (wherein the total of the content of structural units derived from ethylene and the content of structural units derived from an α-olefin having 3 or more carbon atoms is 100 mol %); Requirement (b-2): the weight average molecular weight (Mw) determined by gel permeation chromatography (GPC) is 1,000 to 100,000; Requirement (b-3): The modified ethylene-α-olefin copolymer (B) is a modified copolymer having a moiety derived from an organosilicon compound containing one or more carbon-carbon unsaturated bonds, and the content of the moiety derived from the organosilicon compound in 100% by mass of the modified copolymer is 0.5 to 50% by mass.

[11] The method for producing a rubber composition according to the above

[10] , wherein the modified ethylene-α-olefin copolymer (B) is a modified copolymer obtained by modifying an ethylene-α-olefin copolymer (B') produced by the following method (α) with the organosilicon compound; Method (α): A method comprising a step of copolymerizing ethylene and an α-olefin having 3 or more carbon atoms in the presence of an olefin polymerization catalyst comprising a bridged metallocene compound (P) represented by the above-mentioned formula [I] and at least one compound (Q) selected from the group consisting of an organometallic compound (Q-1), an organoaluminum oxy compound (Q-2), and a compound (Q-3) which reacts with the bridged metallocene compound (P) to form an ion pair.

[12] In the formula [I], R 13 and R 14 wherein either or both of the above is an aryl group.

[13] In the formula [I], R 13 and R 14 are both aryl groups, and R 2 and R 3 wherein either one of the above is a saturated hydrocarbon group having 4 carbon atoms.

[14] The method for producing a rubber composition according to any one of the items

[10] to

[13] , wherein, in the step, the amount of the modified ethylene-α-olefin copolymer (B) is 10 to 40 parts by mass, the amount of the inorganic filler (C) is 10 to 80 parts by mass, and the mixing ratio of the coupling agent (D) is 1.5 to 15 mass% in 100 mass% of the total of the inorganic filler (C) and the coupling agent (D); in the requirement (b-1), the content ratio of structural units derived from ethylene is 40 to 60 mol%; in the requirement (b-2), the weight average molecular weight (Mw) determined by gel permeation chromatography (GPC) is 2,000 to 30,000; and in the requirement (b-3), the content ratio of the moiety derived from the organosilicon compound in 100 mass% of the modified copolymer is 0.5 to 20 mass%.

[15] The method for producing a rubber composition according to any one of the items

[10] to

[14] , wherein, in the requirement (b-3), the organosilicon compound is a compound containing one or more carbon-carbon unsaturated bonds and one or more trialkoxysilyl groups, and the inorganic filler (C) is a silicon-containing filler. EXAMPLES

[0172] The rubber composition of the present disclosure will be described more specifically below based on examples, but the rubber composition of the present disclosure is not limited to these examples.

[0173] [Methods for measuring raw material structure, molecular weight, etc.] The structure, molecular weight, etc. of each copolymer were measured by the following methods.

[0174] <Ethylene content (mol%)> 13 The ethylene content (mol%) of each copolymer was measured by C-NMR method using the following equipment and conditions: ECP500 nuclear magnetic resonance apparatus manufactured by JEOL Ltd. Solvent: mixed solvent of orthodichlorobenzene / heavy benzene (80% by volume / 20% by volume), sample concentration: 55 mg / 0.6 mL, measurement temperature: 120°C, observation nucleus: 13 The measurements were performed under the following conditions: C (125 MHz), sequence: single pulse proton decoupling, pulse width: 4.7 μsec (45° pulse), repetition time: 5.5 sec, number of integrations: 10,000 or more, chemical shift reference value: 27.50 ppm. 13 The ethylene content was determined from the C-NMR spectrum based on the reports of GJ Ray (Macromolecules, 10, 773 (1977)), JC Randal (Macromolecules, 15, 353 (1982)), and K. Kimura (Polymer, 25, 4418 (1984)).

[0175] <Number average molecular weight, weight average molecular weight and molecular weight distribution> The weight average molecular weight (Mw) and number average molecular weight (Mn) were calculated in terms of polystyrene molecular weight by gel permeation chromatography (GPC) according to the general calibration procedure, and the molecular weight distribution (Mw / Mn) was calculated from these values. High-speed GPC measuring device: HLC-8320GPC (Tosoh Corporation) Separation column: TSKgel Super MultiporeHZ-M (Tosoh Corporation) 4 pieces connected in series Column temperature: 40℃ Mobile phase: Tetrahydrofuran (Wako Pure Chemical Industries, Ltd.) Mobile phase flow rate: 0.35mL / min Sample concentration: 5.5g / L Sample injection volume: 20 μL Detector: Differential refractometer Standard polystyrene: PStQuick MP-M (manufactured by Tosoh Corporation).

[0176] <Content of parts derived from organosilicon compounds> 1 The content (mass%) of the site derived from the organosilicon compound (modified site) in the modified copolymer (B) was measured by H-NMR method using the following equipment and conditions. A Bruker Biospin AVANCEIIIcryo-500 nuclear magnetic resonance spectrometer (500MHz) was used, and the solvent was 1,1,2,2-tetrachloroethane-d 2 The measurement was performed under the following conditions: measurement temperature: 120° C., spectrum width: 20 ppm, pulse repetition time: 30 seconds, pulse width: 5.00 μsec. 1 The content ratio was determined by calculating the area ratio of peaks characteristic of the organosilicon compound (peaks of methoxy groups in the case of vinyltrimethoxysilane) from the H-NMR spectrum.

[0177] [Production of modified copolymer (B)] [Production Example 1] 250 mL of heptane was charged into a 1 L glass polymerization vessel that had been thoroughly purged with nitrogen, and the temperature inside the system was raised to 50°C. Then, ethylene was continuously fed into the vessel at a flow rate of 25 L / h, propylene at 75 L / h, and hydrogen at 100 L / h, and the vessel was stirred at a rotation speed of 600 rpm. Next, 0.2 mmol of triisobutylaluminum was charged into the vessel, followed by 0.688 mmol of MMAO and [diphenylmethylene(η 5 -cyclopentadienyl)(η 5 The polymerization was started by charging 0.00230mmol of 1,2-di-t-butylfluorenyl)zirconium dichloride in toluene for 15 minutes or more into the polymerization vessel. Ethylene, propylene, and hydrogen were then continuously fed and the polymerization was carried out at 50°C for 15 minutes. A small amount of isobutyl alcohol was added to the system to terminate the polymerization, and the unreacted ethylene, propylene, and hydrogen were purged. The resulting polymerization solution was washed three times with 1000mL of 0.2mol / L hydrochloric acid and three times with 1000mL of distilled water, dried over magnesium sulfate, and the solvent was removed under reduced pressure to obtain a crude ethylene-propylene copolymer.

[0178] In a 1L stainless steel autoclave, 100mL of a hexane solution of 0.5% by mass Pd / alumina catalyst (hydrogenation catalyst) and 500mL of a 30% by mass hexane solution of the obtained crude ethylene-propylene copolymer were added, the autoclave was sealed, and the atmosphere was replaced with nitrogen. The temperature was then raised to 140°C while stirring, and the system was replaced with hydrogen. The pressure was then raised to 1.5MPa with hydrogen and the hydrogenation reaction was carried out for 15 minutes. The reaction solution was filtered to remove the hydrogenation catalyst, and the solvent was distilled off under reduced pressure. The mixture was dried at 80°C under reduced pressure for 24 hours to obtain an ethylene-propylene copolymer (B1'). The ethylene content of this ethylene-propylene copolymer (B1') was 51.4 mol%, Mw was 13,000, and Mw / Mn was 1.9.

[0179] [Production Example 2] 760 mL of heptane and 120 g of propylene were charged into a 2 L stainless steel autoclave that had been thoroughly purged with nitrogen, and the temperature inside the system was raised to 150°C. Then, 0.85 MPa of hydrogen and 0.19 MPa of ethylene were fed to adjust the total pressure to 3 MPaG. Next, 0.4 mmol of triisobutylaluminum, [diphenylmethylene (η 5 -3-n-butylcyclopentadienyl)(η 5 0.0002mmol of N,N-dimethylanilinium tetrakis(pentafluorophenyl)borate was added with nitrogen and polymerization was started by changing the stirring speed to 400rpm. Then, the total pressure was kept at 3MPaG by continuously supplying only ethylene, and polymerization was carried out at 150℃ for 5 minutes. After the polymerization was stopped by adding a small amount of ethanol to the system, unreacted ethylene, propylene, and hydrogen were purged. The obtained polymerization solution was washed three times with 1000mL of 0.2mol / L hydrochloric acid and then three times with 1000mL of distilled water, dried over magnesium sulfate, and the solvent was distilled off under reduced pressure. The obtained polymer was dried at 80℃ under reduced pressure for 24 hours to obtain ethylene-propylene copolymer (B2'). The ethylene-propylene copolymer (B2') had an ethylene content of 49.5 mol%, Mw of 5,100, and Mw / Mn of 1.7.

[0180] [Production Example 3] 710 mL of heptane and 145 g of propylene were charged into a 2 L stainless steel autoclave that had been thoroughly purged with nitrogen, and the temperature inside the system was raised to 150°C. Then, 0.40 MPa of hydrogen and 0.27 MPa of ethylene were fed to adjust the total pressure to 3 MPaG. Next, 0.4 mmol of triisobutylaluminum, [methylphenylmethylene (η 5 -cyclopentadienyl)(η 50.0001mmol of N,N-dimethylanilinium tetrakis(pentafluorophenyl)borate was added with nitrogen and polymerization was started by changing the stirring speed to 400 rpm. Then, polymerization was continued for 5 minutes at 150°C while maintaining the total pressure at 3MPaG by continuously supplying only ethylene. After stopping the polymerization by adding a small amount of ethanol to the system, unreacted ethylene, propylene, and hydrogen were purged. The obtained polymerization solution was washed three times with 1000mL of 0.2mol / L hydrochloric acid and then three times with 1000mL of distilled water, dried over magnesium sulfate, and the solvent was removed under reduced pressure to obtain a crude ethylene-propylene copolymer.

[0181] In a 1L stainless steel autoclave, 100mL of a hexane solution of 0.5% Pd / alumina catalyst (hydrogenation catalyst) and 500mL of a 30% hexane solution of the obtained crude ethylene-propylene copolymer were added, the autoclave was sealed, and nitrogen replacement was performed. The temperature was then raised to 140°C while stirring, and the system was replaced with hydrogen. The pressure was then raised to 1.5MPa with hydrogen and the hydrogenation reaction was performed for 15 minutes. The reaction solution was filtered to remove the hydrogenation catalyst, and the solvent was distilled off under reduced pressure. The mixture was dried at 80°C under reduced pressure for 24 hours to obtain an ethylene-propylene copolymer (B3'). The ethylene content of this ethylene-propylene copolymer (B3') was 53.1 mol%, Mw was 8,600, and Mw / Mn was 1.8.

[0182] [Denaturation Example 1] In a 1L glass autoclave, 383.7g of unmodified ethylene-propylene copolymer (B1') and 53.8g of vinyltrimethoxysilane were placed, and the atmosphere was replaced with nitrogen. The temperature was then raised to 160°C with stirring, and 1.2g of di-t-butyl peroxide was fed over 1 hour, and the reaction was allowed to continue for 1.5 hours after the completion of the feeding. Next, the pressure was reduced for 1 hour while gradually passing nitrogen through the vacuum pump to remove impurities (unreacted vinyltrimethoxysilane and decomposition products of di-t-butyl peroxide). The above operations yielded vinyltrimethoxysilane-modified ethylene-propylene copolymer (B-1). This is also referred to as "liquid silane-modified copolymer (B-1)" below.

[0183] [Denaturation Example 2] 383.7 g of unmodified ethylene-propylene copolymer (B1') was placed in a 1 L glass autoclave, and the atmosphere was replaced with nitrogen. Next, the temperature was raised to 160°C with stirring, and then 53.8 g of vinyltrimethoxysilane and 1.2 g of di-t-butyl peroxide were fed over 1 hour, and the reaction was allowed to proceed for 1.5 hours after the completion of the feeding. Next, the pressure was reduced for 1 hour while gradually passing nitrogen through the vacuum pump to remove impurities (decomposition products of unreacted vinyltrimethoxysilane and di-t-butyl peroxide). The above operations yielded vinyltrimethoxysilane-modified ethylene-propylene copolymer (B-2). This is also referred to as "liquid silane-modified copolymer (B-2)" below.

[0184] [Denaturation Example 3] The same procedure as in Modification Example 2 was repeated, except that the amount of unmodified ethylene-propylene copolymer (B1') was changed to 348.6 g, the amount of vinyltrimethoxysilane was changed to 97.8 g, and the amount of di-t-butyl peroxide was changed to 2.2 g. The product silane-modified ethylene-propylene copolymer is hereinafter also referred to as "liquid silane-modified copolymer (B-3)".

[0185] [Denaturation Example 4] The same procedure as in Modification Example 2 was repeated, except that 383.7 g of unmodified ethylene-propylene copolymer (B1') was changed to 398.1 g of unmodified ethylene-propylene copolymer (B2'), the amount of vinyltrimethoxysilane added was changed to 25.4 g, and the amount of di-t-butyl peroxide added was changed to 0.6 g. The product silane-modified ethylene-propylene copolymer is hereinafter also referred to as "liquid silane-modified copolymer (B-4)".

[0186] [Denaturation Example 5] The same procedure as in Modification Example 2 was repeated, except that 383.7 g of unmodified ethylene-propylene copolymer (B1') was changed to 402.3 g of unmodified ethylene-propylene copolymer (B3'), the amount of vinyltrimethoxysilane added was changed to 12.4 g, and the amount of di-t-butyl peroxide added was changed to 0.3 g. The product silane-modified ethylene-propylene copolymer is hereinafter also referred to as "liquid silane-modified copolymer (B-5)".

[0187] [Denaturation Example 6] The same procedure as in Modification Example 5 was repeated except that the amount of unmodified ethylene-propylene copolymer (B3') was changed to 369.3 g, the amount of vinyltrimethoxysilane was changed to 55.2 g, and the amount of di-t-butyl peroxide was changed to 1.2 g. The product silane-modified ethylene-propylene copolymer is hereinafter also referred to as "liquid silane-modified copolymer (B-6)".

[0188] The results of measuring the molecular weight and the like of the liquid silane-modified copolymers (B-1) to (B-6) obtained in Modification Examples 1 to 6 are shown in Table 1.

[0189] [Table 1]

[0190] [Rubber composition components] In the following examples, the following components were used. <Copolymer rubber (A)> Ethylene-propylene-non-conjugated polyene copolymer rubber (EPDM, Mitsui Chemicals, Inc., Mitsui EPT 4045, ML(1+4)100℃=45) <Softener> Paraffinic mineral oil (Idemitsu Kosan Co., Ltd., Diana Process Oil PW-380) <Unmodified Copolymer (B')> Liquid ethylene-propylene copolymer (B1') <Modified copolymer (B) and other modified polymers> Liquid silane-modified copolymers (B-1) to (B-6) · Triethoxysilane-terminated liquid polybutadiene (EVONIK, POLYVEST ST-E 60) <Inorganic filler (C)> Silica (Tosoh Silica Corporation, Nipsil VN3) <Coupling agent (D)> ·Organic silane coupling agent (EVONIK, Si-69) Bis(3-triethoxysilylpropyl) polysulfide <Products containing organic peroxide> Kayacumyl D-40C (Dicumyl peroxide diluted with calcium carbonate etc. to 40% by mass, manufactured by Kayaku Nouryon Co., Ltd.)

[0191] [Production of rubber composition and crosslinked molded product] [Example 1] Using a Labo Plastomill (Toyo Seiki Seisakusho, 4C150 type, volume 60cc), 100 parts by mass of EPDM, 25 parts by mass of liquid silane-modified copolymer (B-1), 36 parts by mass of silica "Nipsil VN3", and 4 parts by mass of organic silane coupling agent "Si-69" were kneaded. The kneading conditions were rotor rotation speed of 50 rpm, set temperature of 130°C, and kneading time of 2.5 minutes. Then, the kneaded material was put into the Labo Plastomill again and kneaded with 7 parts by mass of organic peroxide "Kayakumiru D-40C". The kneading conditions were rotor rotation speed of 40 rpm, set temperature of 40°C, and kneading time of 2.5 minutes. Then, the kneaded material was formed into a sheet shape of 1 mm x 65 mm square and 2 mm x 65 mm square using a heat press machine (Shinto Metal Industries Co., Ltd.) to obtain a crosslinked sheet. The crosslinking conditions were a set temperature of 180°C and a vulcanization time of 10 minutes.

[0192] [Examples 2 to 6 and Comparative Examples 1 to 5] A kneaded product and a crosslinked sheet were obtained in the same manner as in Example 1, except that the compounding composition of the raw materials constituting the rubber composition was changed as shown in Table 2.

[0193] [Method for evaluating the physical properties of crosslinked molded products] The hardness (type A durometer hardness) of the test piece obtained by stacking three crosslinked sheets with a thickness of 2 mm was measured under the conditions of a test temperature of 23°C and a measurement time of 3 seconds according to the method in accordance with JIS K6253-3:2012 "Vulcanized rubber and thermoplastic rubber - Determination of hardness - Part 3: Durometer hardness". From the crosslinked sheet with a thickness of 1 mm, a dumbbell-shaped No. 7 test piece was prepared in accordance with JIS K6251:2017 "Vulcanized rubber and thermoplastic rubber - Determination of tensile properties". The tensile strength at break (Tb) and elongation at break (Eb) of the dumbbell-shaped No. 7 test piece were measured at a test temperature of 23°C and a tensile speed of 200 mm / min according to the method in accordance with JIS K6251:2017 "Vulcanized rubber and thermoplastic rubber - Determination of tensile properties".

[0194] [Table 2]

Claims

1. A rubber composition comprising: The rubber composition comprises one or more copolymer rubbers (A) selected from ethylene / α-olefin copolymer rubbers and ethylene / α-olefin / non-conjugated polyene copolymer rubbers; A modified ethylene / α-olefin copolymer (B) that satisfies the following requirements (b-1) to (b-3); An inorganic filler (C); A coupling agent (D); Contains the content of the modified ethylene / α-olefin copolymer (B) is 1 to 100 parts by mass, and the content of the inorganic filler (C) is 1 to 200 parts by mass, relative to 100 parts by mass of the copolymer rubber (A); The content ratio of the coupling agent (D) is 0.5 to 20 mass% in 100 mass% of the total of the inorganic filler (C) and the coupling agent (D). Rubber composition; Requirement (b-1): the content ratio of structural units derived from ethylene in the ethylene / α-olefin copolymer (B') before modification is 10 to 90 mol % (wherein the total of the content of structural units derived from ethylene and the content of structural units derived from an α-olefin having 3 or more carbon atoms is 100 mol %); Requirement (b-2): the weight average molecular weight (Mw) determined by gel permeation chromatography (GPC) is 1,000 to 100,000; Requirement (b-3): The modified ethylene / α-olefin copolymer (B) is a modified copolymer having a moiety derived from an organosilicon compound containing one or more carbon-carbon unsaturated bonds, and the content of the moiety derived from the organosilicon compound in 100% by mass of the modified copolymer is 0.5 to 50% by mass.

2. In the above requirement (b-1), the content of structural units derived from ethylene is 40 to 60 mol %, In the above requirement (b-2), the weight average molecular weight (Mw) determined by gel permeation chromatography (GPC) is 2,000 to 30,000; In the above requirement (b-3), the content of the moiety derived from the organosilicon compound in 100% by mass of the modified copolymer is 0.5 to 20% by mass. The rubber composition according to claim 1.

3. the content of the modified ethylene / α-olefin copolymer (B) is 10 to 40 parts by mass, and the content of the inorganic filler (C) is 10 to 80 parts by mass, relative to 100 parts by mass of the copolymer rubber (A); The content ratio of the coupling agent (D) is 1.5 to 15 mass% in 100 mass% of the total of the inorganic filler (C) and the coupling agent (D). The rubber composition according to claim 1.

4. In the above-mentioned requirement (b-3), the above-mentioned organosilicon compound is a compound containing one or more carbon-carbon unsaturated bonds and one or more trialkoxysilyl groups, The inorganic filler (C) is a silicon-containing filler; The rubber composition according to claim 1.

5. A belt comprising the rubber composition according to any one of claims 1 to 4 or a crosslinked product thereof.

6. A hose comprising the rubber composition according to any one of claims 1 to 4 or a crosslinked product thereof.

7. A tube comprising the rubber composition according to any one of claims 1 to 4 or a crosslinked product thereof.

8. A sealing material comprising the rubber composition according to any one of claims 1 to 4 or a crosslinked product thereof.

9. A vibration damping material comprising the rubber composition according to any one of claims 1 to 4 or a crosslinked product thereof.

10. A method for producing a rubber composition, comprising the steps of: The manufacturing method includes: one or more copolymer rubbers (A) selected from ethylene / α-olefin copolymer rubbers and ethylene / α-olefin / non-conjugated polyene copolymer rubbers; A modified ethylene / α-olefin copolymer (B) that satisfies the following requirements (b-1) to (b-3); An inorganic filler (C); A coupling agent (D); Mixing the above components, In the above process, the blending amount of the modified ethylene / α-olefin copolymer (B) is 1 to 100 parts by mass, and the blending amount of the inorganic filler (C) is 1 to 200 parts by mass, relative to 100 parts by mass of the copolymer rubber (A); The mixing ratio of the coupling agent (D) is 0.5 to 20 mass% in 100 mass% of the total of the inorganic filler (C) and the coupling agent (D). A method for producing a rubber composition; Requirement (b-1): the content ratio of structural units derived from ethylene in the ethylene / α-olefin copolymer (B') before modification is 10 to 90 mol % (wherein the total of the content of structural units derived from ethylene and the content of structural units derived from an α-olefin having 3 or more carbon atoms is 100 mol %); Requirement (b-2): the weight average molecular weight (Mw) determined by gel permeation chromatography (GPC) is 1,000 to 100,000; Requirement (b-3): The modified ethylene / α-olefin copolymer (B) is a modified copolymer having a moiety derived from an organosilicon compound containing one or more carbon-carbon unsaturated bonds, and the content of the moiety derived from the organosilicon compound in 100% by mass of the modified copolymer is 0.5 to 50% by mass.

11. The method for producing a rubber composition according to claim 10, wherein the modified ethylene / α-olefin copolymer (B) is a modified copolymer obtained by modifying an ethylene / α-olefin copolymer (B') produced by the following method (α) with the organosilicon compound: Method (α): A bridged metallocene compound (P) represented by the following formula [I], at least one compound (Q) selected from the group consisting of an organometallic compound (Q-1), an organoaluminum oxy compound (Q-2), and a compound (Q-3) which reacts with the bridged metallocene compound (P) to form an ion pair; The method includes a step of copolymerizing ethylene and an α-olefin having 3 or more carbon atoms in the presence of an olefin polymerization catalyst comprising: 【Chemistry 1】 [In formula [I], R 1 , R 2 , R 3 , R 4 , R 5 , R 8 , R 9 and R 12 are each independently a hydrogen atom, a hydrocarbon group, or a silicon-containing hydrocarbon group, and adjacent groups may be linked to each other to form a ring structure; R 6 and R 11 are the same group and are a hydrogen atom, a hydrocarbon group, or a silicon-containing hydrocarbon group; R 7 and R 10 are the same group and are a hydrogen atom, a hydrocarbon group, or a silicon-containing hydrocarbon group; R 6 and R 7 may be bonded to a hydrocarbon having 2 to 3 carbon atoms to form a ring structure, R 10 and R 11 may be bonded to a hydrocarbon having 2 to 3 carbon atoms to form a ring structure, R 6 , R 7 , R 10 and R 11 is not a hydrogen atom at the same time, R 13 and R 14 each independently represents a hydrogen atom, a hydrocarbon group, or a silicon-containing hydrocarbon group, and may be linked together to form a ring structure, Y is a carbon atom or a silicon atom; M is Ti, Zr or Hf, Q is a halogen atom, a hydrocarbon group, an anionic ligand or a neutral ligand capable of coordinating with a lone electron pair, j is an integer of 1 to 4, and when j is an integer of 2 or more, multiple Qs may be the same or different.

12. In the formula [I], R 13 and R 14 The method for producing a rubber composition according to claim 11, wherein either or both of the following is an aryl group:

13. In the formula [I], R 13 and R 14 are both aryl groups, and R 2 and R 3 The method for producing a rubber composition according to claim 11, wherein either one of the above is a saturated hydrocarbon group having 4 carbon atoms.

14. In the above step, the amount of the modified ethylene / α-olefin copolymer (B) is 10 to 40 parts by mass, the amount of the inorganic filler (C) is 10 to 80 parts by mass, and the mixing ratio of the coupling agent (D) is 1.5 to 15% by mass relative to 100 parts by mass of the total amount of the inorganic filler (C) and the coupling agent (D), In the above requirement (b-1), the content of structural units derived from ethylene is 40 to 60 mol %, In the above requirement (b-2), the weight average molecular weight (Mw) determined by gel permeation chromatography (GPC) is 2,000 to 30,000; In the above requirement (b-3), the content of the moiety derived from the organosilicon compound in 100% by mass of the modified copolymer is 0.5 to 20% by mass. A method for producing the rubber composition according to claim 10.

15. In the above-mentioned requirement (b-3), the above-mentioned organosilicon compound is a compound containing one or more carbon-carbon unsaturated bonds and one or more trialkoxysilyl groups, The inorganic filler (C) is a silicon-containing filler; A method for producing the rubber composition according to claim 10.

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