JP2009287020A - Rubber composition and tire using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rubber composition with which a tire with significantly improved low pyrogenicity and wear resistance can be produced. <P>SOLUTION: The rubber composition comprises (A) a rubber component containing 10 mass% or more of a modified conjugated diene-based polymer having at least one type of functional group, which has weight-average molecular weight in terms of polystyrene of 200,000 or more as determined by gel permeation chromatography and, based on 100 pts.mass of (A), (B) 20 pts.mass or more of a reinforcing filler and (C) 5-60 pts.mass of an unmodified and/or modified low-molecular-weight aromatic vinyl compound-conjugated diene compound copolymer having weight-average molecular weight of ≥5,000 and <200,000 in its unmodified state or before modification, wherein the modified conjugated diene-based polymer in the (A) component has, as functional groups, an amino group that is protected by a protic amino group or eliminable group and a functional group containing a silicon atom. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a rubber composition and a tire using the rubber composition. More specifically, the present invention relates to a rubber composition that gives a tire with greatly improved low heat buildup and wear resistance, and a tire having the above characteristics using the rubber composition.

  In recent years, demands for reducing the fuel consumption of automobiles are becoming more severe in connection with the movement of global carbon dioxide emission regulations due to the social demand for energy saving and the increasing interest in environmental problems. In order to meet such demands, a reduction in rolling resistance has also been demanded for tire performance. As a technique for reducing the rolling resistance of the tire, although a technique by optimizing the tire structure has been studied, the most common technique is to use a material having lower heat generation as the rubber composition.

  In order to obtain such a rubber composition having a low exothermic property, many technical developments have been made on modified rubbers for rubber compositions using silica or carbon black as a filler. Among them, a method in which the polymerization active terminal of a conjugated diene polymer obtained by anionic polymerization using organolithium is modified with an alkoxysilane derivative containing a functional group that interacts with a filler has been proposed as effective. (For example, see Patent Documents 1, 2, and 3).

  Each of these alkoxysilane derivatives is a silicon compound having an alkoxy group directly bonded to a silicon atom in the molecule and a nitrogen-containing functional group that interacts with the filler. The modified conjugated diene polymer obtained by modification has the effect of reducing the rolling resistance of the tire (improving the low heat buildup) and improving the fracture characteristics and the wear resistance.

On the other hand, with respect to 100 parts by mass of the rubber component containing 10% by mass or more of the modified conjugated diene polymer, 20 parts by mass or more of the reinforcing filler and a low molecular weight having specific properties instead of a softener such as aroma oil. A rubber composition containing 5 to 60 parts by mass of an aromatic vinyl compound-conjugated diene compound copolymer or a modified copolymer thereof is disclosed (for example, see Patent Documents 4 and 5). These rubber compositions also have the effect of improving fracture characteristics, wear resistance, low heat build-up, and the like.
However, in recent years, from the viewpoints of energy saving and environmental problems, further reduction in fuel consumption of automobiles (reduction in rolling resistance of tires) and improvement in wear resistance are desired.

  By the way, as a rubber composition applied to the tread portion of the tire, a rubber composition having a moderately high storage elastic modulus (G ′) is preferable from the viewpoint of dry grip performance. Therefore, a rubber composition having a low loss tangent (tan δ) (low exothermic property) and an appropriate storage elastic modulus (G ′) is demanded. On the other hand, as means for improving the storage elastic modulus (G ′) of the rubber composition, a method of increasing the blending amount of carbon black blended in the rubber composition or N, N as described in Patent Document 6 is used. A technique for blending a bismaleimide having a specific structure such as'-(4,4'-diphenylmethane) -bismaleimide, a reactive group for a rubber component such as polyethylene glycol dimaleate as described in Patent Document 7, and a filler A technique for blending a compound having an adsorbing group is known.

However, when the blending amount of carbon black in the rubber composition is increased, the storage elastic modulus (G ′) of the rubber composition can be improved, but at the same time, the loss tangent (tan δ) of the rubber composition increases. Further, there is a problem that the low heat build-up of the rubber composition is lowered, and further, the Mooney viscosity of the rubber composition is increased and the processability is lowered.
In addition, when the rubber composition contains a compound having a reactive group for the bismaleimide or rubber component and an adsorbing group for the filler, the storage elastic modulus (G ′) of the rubber composition can be improved. The loss tangent (tan δ) of the rubber composition is substantially the same, and the low heat build-up of the rubber composition cannot be sufficiently improved.

JP 2001-158837 A JP 2005-232364 A JP-A-2005-290355 WO2006 / 093051 pamphlet WO2007 / 032209 Pamphlet JP 2002-121326 A JP 2003-176378 A

  An object of the present invention is to provide a rubber composition that gives a tire with greatly improved low heat buildup and wear resistance under such circumstances, and a tire having the above characteristics using the rubber composition. It is what.

As a result of intensive studies to achieve the above object, the present inventors have used a rubber component containing a certain value or more of a modified conjugated diene polymer having a specific functional group, and a reinforcing filler. And the rubber composition containing the low-molecular conjugated diene polymer having a specific property at a predetermined ratio, respectively, has found that the object can be achieved.
The present invention has been completed based on such findings.

That is, the present invention
[1] (A) A rubber component containing 10% by mass or more of a modified conjugated diene polymer having at least one functional group having a polystyrene-equivalent weight average molecular weight of 200,000 or more as measured by gel permeation chromatography, and 100 masses thereof. (B) 20 parts by mass or more of the reinforcing filler, and (C) unmodified or modified and unmodified and / or modified with a weight average molecular weight of 5,000 to less than 200,000. An amino group containing 5 to 60 parts by mass of a low molecular weight conjugated diene polymer and the modified conjugated diene polymer in the component (A) protected with a protic amino group or a detachable group as a functional group And a rubber composition having a functional group containing a silicon atom,
[2] A primary amino group protected by a protic amino group or a detachable group, or a primary amino group or a secondary amino group protected by a secondary amino group or a detachable group The rubber composition of [1] above,
[3] The rubber composition according to claim 1 or 2, wherein the functional group containing a silicon atom is a hydrocarbyloxy group, a hydroxy group or a halogen atom directly bonded to the silicon atom.
[4] The rubber composition according to any one of the above [1] to [3], wherein the modified conjugated diene polymer in the component (A) has a functional group at a terminal.
[5] The above [1], wherein the modified conjugated diene polymer in the component (A) has an amino group protected with a protic amino group or a detachable group at the same end and a functional group containing a silicon atom. [3] any rubber composition,
[6] The rubber composition according to the above [5], wherein the same terminal is a polymerization termination terminal.
[7] The modified conjugated diene polymer in component (A) has the following general formula (1) as a modifier at the active end of the conjugated diene polymer having an active end.

[Wherein, A ¹ is a halogen atom or a hydrocarbyloxy group having 1 to 20 carbon atoms, R ² is a hydrocarbon group R ³ is a hydrocarbon group, L ¹ is a detachable functional group, and L ² is detachable. When it is a possible group or a hydrocarbon group and L ² is a detachable functional group, it may have the same structure as L ¹ or a different structure, and L ¹ and L ² may be bonded. n represents 0 or 1, and m represents 1 or 2. ]
General formula (2)

Wherein R ⁴ is a hydrocarbon group having 1 to 20 carbon atoms, R ⁵ is a hydrocarbon group having 1 to 12 carbon atoms, A ² and A ³ are each independently a halogen atom or hydrocarbyloxy having 1 to 20 carbon atoms. Group L ³ is a detachable functional group or hydrocarbon group, L ⁴ is a detachable functional group, k is 0 or 1, and f is an integer of 1 to 10.)
And general formula (3)

(In the formula, A ⁴ is a halogen atom or a hydrocarbyloxy group having 1 to 20 carbon atoms, R ⁶ is a hydrocarbon group having 1 to 20 carbon atoms, R ⁷ is a hydrocarbon group having 1 to 12 carbon atoms, and L ⁵ is a desorbing group. A separable functional group or hydrocarbon group, q represents ˜0 or 1.)
The rubber composition according to any one of the above [1] to [6], which is selected from silane compounds represented by:
[8] The rubber composition according to any one of the above [1] to [7], wherein the detachable group is a trimethylsilyl group,
[9] The modifier is N, N-bis (trimethylsilyl) aminopropylmethyldimethoxysilane, N, N-bis (trimethylsilyl) aminopropylmethyldiethoxysilane, N, N-bis (trimethylsilyl) aminopropylmethylmethoxychlorosilane, or The rubber composition of the above [7] or [8], which is N, N-bis (trimethylsilyl) aminopropylmethylethoxychlorosilane,
[10] The modifier is 1-trimethylsilyl-2-ethoxy-2-methyl-1-aza-2-sila-cyclopentane, 1-trimethylsilyl-2-methoxy-2-methyl-1-aza-2-silacyclo [7] or [8] above which is pentane, 1-trimethylsilyl-2,2-diethoxy-1-aza-2-silacyclopentane or 1-trimethylsilyl-2,2-dimethoxy-1-aza-2-silacyclopentane ] Rubber composition,
[11] The conjugated diene polymer in component (A) reacts with the active end of the conjugated diene polymer having an active end, and then a silane compound is involved in the presence of a condensation accelerator. The rubber composition according to any one of the above [7] to [10], which is obtained by performing a condensation reaction
[12] The modified conjugated diene polymer in the component (A) hydrolyzes a group derived from a silane compound formed by bonding to the active terminal of the conjugated diene polymer, and the protected amino group in the group is converted to a protected amino group. The rubber composition according to any one of the above [7] to [11], which is formed by conversion into a free amino group
[13] The rubber composition according to any one of the above [1] to [12], wherein the modified conjugated diene polymer in component (A) is polymerized using an organic alkali metal compound or a rare earth metal compound,
[14] The rubber composition according to the above [13], wherein the organic alkali metal compound is alkyl lithium.
[15] The above-mentioned [1] to [14], wherein the modified conjugated diene polymer in component (A) is a 1,3-butadiene homopolymer or a copolymer of 1,3-butadiene and an aromatic vinyl compound. ] Any rubber composition,
[16] The rubber composition according to the above [15], wherein the aromatic vinyl compound is styrene.
[17] The rubber composition according to any one of the above [1] to [16], wherein the reinforcing filler of the component (B) is carbon black and / or silica.
[18] The rubber composition according to [17], wherein the total content of carbon black and silica is 20 to 120 parts by mass with respect to 100 parts by mass of (A) the rubber component,
[19] The rubber composition according to the above [17] or [18], wherein the silica content is 50 parts by mass or more with respect to 100 parts by mass of the rubber component (A),
[20] The rubber according to any one of [1] to [19], wherein the unmodified and / or modified low molecular weight conjugated diene polymer of component (C) is a low molecular weight aromatic vinyl compound-conjugated diene compound copolymer. Composition,
[21] The rubber composition according to any one of [1] to [20], wherein the aromatic vinyl compound unit in the unmodified and / or modified low molecular weight aromatic vinyl compound-conjugated diene compound copolymer is a styrene unit.
[22] The rubber according to any one of [1] to [21], wherein the conjugated diene compound unit in the unmodified and / or modified low molecular weight aromatic vinyl compound-conjugated diene compound copolymer is a 1,3-butadiene unit. Composition,
[23] The rubber composition according to [21] or [22] above, wherein the unmodified and / or modified low molecular weight aromatic vinyl compound-conjugated diene compound copolymer is a solution-polymerized styrene-butadiene copolymer rubber.
[24] Any of the above 1 to 23, wherein the unmodified and / or modified low molecular weight conjugated diene polymer of component (C) contains 10% by mass of a modified low molecular weight conjugated diene polymer having at least one functional group. The rubber composition according to
Any one of the above rubber compositions [1] to [23],
[25] The rubber composition according to the above [24], wherein the functional group is a functional group containing nitrogen, silicon, or tin,
[26] The functional group containing nitrogen is a primary amino group, a primary amino group protected with a detachable group, a substituted amino group, an amide group, an imino group, an imidazole residue, a nitrile group or a pyridyl group. The rubber composition of the above [25],
[27] The rubber composition according to the above [26], wherein the detachable protecting group is a trimethylsilyl group,
[28] The modifier is N, N-bis (trimethylsilyl) aminopropylmethyldimethoxysilane, N, N-bis (trimethylsilyl) aminopropylmethyldiethoxysilane, N, N-bis (trimethylsilyl) aminopropylmethylmethoxychlorosilane, or The rubber composition according to any one of the above [25] to [27], which is N, N-bis (trimethylsilyl) aminopropylmethylethoxychlorosilane;
[29] The modifier is 1-trimethylsilyl-2-ethoxy-2-methyl-1-aza-2-sila-cyclopentane, 1-trimethylsilyl-2-methoxy-2-methyl-1-aza-2-silacyclo [25] to [27] which are pentane, 1-trimethylsilyl-2,2-diethoxy-1-aza-2-silacyclopentane or 1-trimethylsilyl-2,2-dimethoxy-1-aza-2-silacyclopentane. ] Any rubber composition,
[30] The functional group containing nitrogen is represented by the following general formula (4).

[Wherein, R ⁸ and R ⁹ each independently represents an alkyl group having 1 to 12 carbon atoms, a cycloalkyl group having 3 to 12 carbon atoms, or an aralkyl group having 7 to 12 carbon atoms. ]
A substituted amino group represented by general formula (5):

[Wherein, R ¹⁰ represents an alkylene group having 3 to 16 methylene groups, a substituted alkylene group, an oxyalkylene group or an N-alkylaminoalkylene group. ]
The rubber composition according to the above [25], which is a group selected from cyclic amino groups represented by:
[31] The modified product of the low molecular weight conjugated diene polymer as the component (C) is bonded to the active end of the low molecular weight conjugated diene polymer having an active end by the following general formula (6).

[In the formula, A ⁵ represents (thio) epoxy group, (thio) isocyanate group, (thio) carbonyl group, (thio) formyl group, imine residue, amide group, isocyanuric acid triester residue, (thio) carboxyl One having at least one functional group selected from an acid hydrocarbyl ester residue, a metal salt residue of (thio) carboxylic acid, a carboxylic acid anhydride residue, a carboxylic acid halide residue, and a carbonic acid dihydrocarbyl ester residue A valent group, R ¹¹ and R ¹² are each independently a monovalent aliphatic hydrocarbon group having 1 to 20 carbon atoms or a monovalent aromatic hydrocarbon group having 6 to 18 carbon atoms, and R ¹³ is a single bond or carbon. indicates the number of 1 to 20 divalent inert hydrocarbon group, n is an integer of 1 to 3, if the OR ¹¹ there are multiple to a plurality of OR ¹¹ may be the same or different, R ¹² is If there are multiple, multiple R ¹² It may be the same or different, do not include active proton and onium salt in the molecule. ]
And a partial condensate thereof, and the general formula (7)
R ¹⁴ _p -Si- (OR ¹⁵ ) _4-p (7)
[Wherein, R ¹⁴ and R ¹⁵ each independently represent a monovalent aliphatic hydrocarbon group having 1 to 20 carbon atoms or a monovalent aromatic hydrocarbon group having 6 to 18 carbon atoms; an integer 2, if the OR ¹⁵ there are multiple to a plurality of OR ¹⁵ may be the same or different, if R ¹⁴ is plural, R ¹⁴ may be the same or different in the molecule Does not include active protons and onium salts. ]
The rubber composition according to any one of the above [25] to [30], wherein the rubber composition is obtained by reacting at least one selected from the hydrocarbyloxysilane compound represented by:
[32] A modified product of the conjugated diene polymer of component (C) is represented by the following general formula (8):
R ¹⁶ _a ZX _b (8)
[Wherein R ¹⁶ is an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 3 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, or an aralkyl group having 7 to 20 carbon atoms, and Z is a tin atom or silicon. An atom, X represents a chlorine atom or a bromine atom, a is 0 to 3, b is 1 to 4, and when there are a plurality of R ^{16 s} , a plurality of R ^{11 s} may be the same or different; In some cases, multiple Xs may be the same or different and a + b = 4. ]
The rubber composition according to any one of the above [25] to [31], which has at least one tin-carbon bond or silicon-carbon bond derived from a coupling agent represented by:
[33] Any of the above [25] to [32], wherein the functional group of the modified product of the low molecular weight conjugated diene polymer of component (C) has an interaction with the reinforcing filler of component (B). Any rubber composition,
[34] The above-mentioned [1], wherein the unmodified and / or modified low molecular weight conjugated diene polymer of the component (C) is an unmodified product or a property before modification and has a weight average molecular weight of 20,000 to 200,000. ] To [33] any rubber composition,
[35] The above-mentioned [34], wherein the unmodified and / or modified low molecular weight conjugated diene polymer of the component (C) is an unmodified product or a property before modification and has a weight average molecular weight of 50,000 to 150,000. ], The rubber composition according to
[36] The modified conjugated diene polymer in the component (A) has, as functional groups, an amino group protected with a protic amino group or a detachable group, and a functional group containing a silicon atom, And the modified low molecular weight conjugated diene polymer in the component (C) has, as functional groups, an amino group protected with a protic amino group or a detachable group and a functional group containing a silicon atom [1 ] To [35] any rubber composition,
[37] (A) The rubber composition of the above [1] to [36], wherein the rubber component comprises natural rubber and / or synthetic isoprene rubber, and [38] the rubber composition of any of [1] to [37] above. A tire characterized by using an object is provided.

  According to the present invention, there is provided a rubber composition that gives a tire that maintains good dry clip performance and has greatly improved low heat buildup and wear resistance, and a tire having the above characteristics using the rubber composition. Can be provided.

First, the rubber composition of the present invention will be described.
The rubber composition of the present invention comprises the following (A) a rubber component containing a modified conjugated diene polymer having at least one functional group, (B) a reinforcing filler, (C) unmodified and / or It is a composition containing a modified low molecular weight conjugated diene polymer.
[(A) Rubber component]
In the rubber composition of the present invention, the rubber component used as the component (A) is a modified conjugated diene polymer having at least one functional group (hereinafter sometimes simply referred to as a modified conjugated diene polymer) 10. It is necessary that the modified conjugated diene polymer contains at least mass% and has an amino group protected with a protic amino group or a detachable group as a functional group and a functional group containing a silicon atom. .

(Modified conjugated diene polymer)
The modified conjugated diene polymer is preferably a copolymer of 1,3-butadiene and an aromatic vinyl compound or a 1,3-butadiene homopolymer. Examples of the aromatic vinyl compound include styrene, α-methylstyrene, 1-vinylnaphthalene, 3-vinyltoluene, ethylvinylbenzene, divinylbenzene, 4-cyclohexylstyrene, 2,4,6-trimethylstyrene, and the like. Styrene is preferred.
The modified conjugated diene polymer preferably has a glass transition point (Tg) of 10 ° C. or lower. This is because if Tg is 10 ° C. or lower, the rolling resistance can be further reduced and the flexibility of the rubber composition at low temperatures can be increased.
In the modified conjugated diene polymer, the functional group may be present in at least one position selected from a polymerization initiation side terminal, a polymerization termination side terminal, a main chain, and a side chain. It is preferable to have an amino group protected with a protic amino group or a detachable group at the same end, and a functional group containing a silicon atom, and in particular, the same end is a polymerization termination side end. Preferably there is.

Examples of the amino group protected with a protic amino group or a detachable group in the modified conjugated diene polymer include a primary amino group and a secondary amino group, or a primary amino protected with a detachable group. And a secondary amino group, and a primary amino group or a primary amino group protected with a detachable group is particularly preferable.
As the detachable group, for example, a trimethylsilyl group is preferable. Specifically, in the case of a primary amino group, an N, N-bis (trimethylsilyl) group is used. In the case of a secondary amino group, an N-trimethylsilyl group is used. Can be mentioned.
On the other hand, examples of the functional group containing a silicon atom include a hydrocarboxy group, a hydroxy group, and a halogen atom that are directly bonded to the silicon atom. Here, as the hydrocarbyloxy group, those having 1 to 20 carbon atoms, specifically, alkoxy groups having 1 to 20 carbon atoms, alkenyloxy groups having 2 to 20 carbon atoms, aryloxy groups having 6 to 18 carbon atoms, carbon The aralkyloxy group of several 7-18 can be mentioned. Examples of the halogen atom include a chlorine atom and a bromine atom.

The modified conjugated diene polymer is preferably polymerized by anionic polymerization using an organic alkali metal compound as a polymerization initiator, or polymerized by coordination polymerization using a rare earth metal compound as a polymerization initiator.
<Anionic polymerization>
As the organic alkali metal compound, it is preferable to use a hydrocarbyl lithium compound, a lithium amide compound, or a Group 1 metal alkoxide. Examples of the Group 1 metal of the Group 1 metal alkoxide include lithium, sodium, potassium, rubidium, and cesium. When a hydrocarbyl lithium compound is used as a polymerization initiator, a conjugated diene polymer having a hydrocarbyl group at the polymerization initiation terminal and the other terminal being a polymerization active site is obtained. On the other hand, when a lithium amide compound is used as a polymerization initiator, a conjugated diene polymer having a nitrogen-containing functional group at the polymerization initiation terminal and the other terminal being a polymerization active site is obtained.
In addition, the usage-amount as a polymerization initiator of organolithium compounds, such as a hydrocarbyl lithium compound and a lithium amide compound, or a group 1 metal alkoxide has the preferable range of 0.2-20 mmol (mmol) per 100g of monomers.

  Examples of the hydrocarbyl lithium compound include ethyl lithium, n-propyl lithium, isopropyl lithium, n-butyl lithium, sec-butyl lithium, tert-octyl lithium, n-decyl lithium, phenyl lithium, 2-naphthyl lithium, and 2-butylphenyl. Examples include lithium, 4-phenyl-butyllithium, cyclohexyllithium, cyclopentyllithium, reaction products of diisopropenylbenzene and butyllithium, and among these, ethyllithium, n-propyllithium, isopropyllithium, n-butyl Alkyl lithium such as lithium, sec-butyl lithium, tert-octyl lithium and n-decyl lithium is preferable, and n-butyl lithium is particularly preferable.

  On the other hand, the lithium amide compounds include lithium hexamethylene imide, lithium pyrrolidide, lithium piperidide, lithium heptamethylene imide, lithium dodecamethylene imide, lithium dimethylamide, lithium diethylamide, lithium dipropylamide, lithium dibutylamide, lithium Dihexylamide, lithium diheptylamide, lithium dioctylamide, lythym-2-ethylhexylamide, lithium didecylamide, lithium-N-methylpiperazide, lithium ethylpropylamide, lithium ethylbutyramide, lithium methylbutyramide, lithium ethylbenzylamide, Examples include lithium methylphenethylamide.

  The lithium amide compound may be preliminarily prepared from a secondary amine and a lithium compound and used for the polymerization reaction, but may be generated in a polymerization system. Here, as the secondary amine, in addition to dimethylamine, diethylamine, dibutylamine, dioctylamine, dicyclohexylamine, diisobutylamine and the like, azacycloheptane (ie, hexamethyleneimine), 2- (2-ethylhexyl) pyrrolidine, 3 -(2-propyl) pyrrolidine, 3,5-bis (2-ethylhexyl) piperidine, 4-phenylpiperidine, 7-decyl-1-azacyclotridecane, 3,3-dimethyl-1-azacyclotetradecane, 4- Dodecyl-1-azacyclooctane, 4- (2-phenylbutyl) -1-azacyclooctane, 3-ethyl-5-cyclohexyl-1-azacycloheptane, 4-hexyl-1-azacycloheptane, 9-isoamyl -1-Azacycloheptadecane, 2-methyl-1-aza Chloheptade-9-ene, 3-isobutyl-1-azacyclododecane, 2-methyl-7-tert-butyl-1-azacyclododecane, 5-nonyl-1-azacyclododecane, 8- (4′-methylphenyl) ) -5-pentyl-3-azabicyclo [5.4.0] undecane, 1-butyl-6-azabicyclo [3.2.1] octane, 8-ethyl-3-azabicyclo [3.2.1] octane, 1-propyl-3-azabicyclo [3.2.2] nonane, 3- (t-butyl) -7-azabicyclo [4.3.0] nonane, 1,5,5-trimethyl-3-azabicyclo [4. 4.0] cyclic amines such as decane. On the other hand, as the lithium compound, the hydrocarbyl lithium compound can be used.

    In the present invention, it is preferable to use alkyl lithium as the organic alkali metal compound of the polymerization initiator. Further, the method for producing the modified conjugated diene polymer by anionic polymerization using the organic alkali metal compound as a polymerization initiator is not particularly limited. For example, in a hydrocarbon solvent inert to the polymerization reaction, the conjugated A conjugated diene polymer can be produced by polymerizing a diene compound alone or a mixture of a conjugated diene compound and an aromatic vinyl compound. Here, as the hydrocarbon solvent inert to the polymerization reaction, propane, n-butane, isobutane, n-pentane, isopentane, n-hexane, cyclohexane, propene, 1-butene, isobutene, trans-2-butene, cis -2-butene, 1-pentene, 2-pentene, 1-hexene, 2-hexene, benzene, toluene, xylene, ethylbenzene and the like. These may be used alone or in combination of two or more.

The anionic polymerization may be performed in the presence of a randomizer. The randomizer can control the microstructure of the conjugated diene compound. For example, the randomizer can control the 1,2-bond content of a butadiene unit in a polymer using butadiene as a monomer, or can be styrene as a monomer. And butadiene units of a copolymer using butadiene are randomized.
Examples of the randomizer include dimethoxybenzene, tetrahydrofuran, dimethoxyethane, diethylene glycol dibutyl ether, diethylene glycol dimethyl ether, bistetrahydrofurylpropane, triethylamine, pyridine, N-methylmorpholine, N, N, N ′, N′-tetramethylethylenediamine, 1 , 2-dipiperidinoethane, potassium t-amylate, potassium t-butoxide, sodium t-amylate and the like. The amount of these randomizers used is preferably in the range of 0.01 to 100 molar equivalents per mole of the organic alkali metal compound as the polymerization initiator.

  The anionic polymerization may be performed by any of solution polymerization, gas phase polymerization, and bulk polymerization, but in the case of solution polymerization, the concentration of the monomer in the solution is preferably in the range of 5 to 50% by mass, A range of 10 to 30% by mass is more preferable. In addition, when using together a conjugated diene compound and an aromatic vinyl compound as a monomer, the content rate of the aromatic vinyl compound in a monomer mixture has the preferable range of 3-50 mass%, and 4-45 mass%. The range of is more preferable. Further, the polymerization mode is not particularly limited, and may be batch type or continuous type.

  The polymerization temperature of the anionic polymerization is preferably in the range of 0 to 150 ° C, more preferably in the range of 20 to 130 ° C. The polymerization can be carried out under generated pressure, but it is usually preferable to carry out the polymerization under a pressure sufficient to keep the monomer used in a substantially liquid phase. Here, when the polymerization reaction is carried out under a pressure higher than the generated pressure, it is preferable to pressurize the reaction system with an inert gas. In addition, it is preferable to use raw materials such as monomers, polymerization initiators, and solvents used for polymerization from which reaction inhibitors such as water, oxygen, carbon dioxide, and protic compounds have been removed in advance.

<Coordination polymerization>
On the other hand, when the modified conjugated diene polymer is produced by coordination polymerization using a rare earth metal compound as a polymerization initiator, the following (A) component, (B) component, and (C) component may be used in combination: preferable.
The component (a) used for the coordination polymerization is selected from a rare earth metal compound, a complex compound of a rare earth metal compound and a Lewis base, and the like. Here, examples of rare earth metal compounds include rare earth element carboxylates, alkoxides, β-diketone complexes, phosphates and phosphites, and Lewis bases include acetylacetone, tetrahydrofuran, pyridine, N, N. -Dimethylformamide, thiophene, diphenyl ether, triethylamine, an organic phosphorus compound, monovalent or divalent alcohol, etc. are mentioned. As the rare earth element of the rare earth metal compound, lanthanum, neodymium, praseodymium, samarium and gadolinium are preferable, and among these, neodymium is particularly preferable. Specific examples of the component (a) include neodymium tri-2-ethylhexanoate, complex compounds thereof with acetylacetone, neodymium trineodecanoate, complex compounds thereof with acetylacetone, neodymium tri-n-butoxide, and the like. It is done. These components (a) may be used alone or in combination of two or more.

The component (b) used for the coordination polymerization is selected from organoaluminum compounds. As the organoaluminum compound, specifically, the formula: R ¹² trihydrocarbyl aluminum compound represented by ₃ Al, wherein: hydrocarbyl during hydrocarbyl aluminum hydride (formula represented by R ¹² ₂ AlH or R ¹² AlH _2, R ¹² are each independently a hydrocarbon group having 1 to 30 carbon atoms), hydrocarbylaluminoxane compounds having a hydrocarbon group having 1 to 30 carbon atoms, and the like. Specific examples of the organoaluminum compound include trialkylaluminum, dialkylaluminum hydride, alkylaluminum dihydride, and alkylaluminoxane. These compounds may be used alone or in combination of two or more. In addition, as (b) component, it is preferable to use aluminoxane and another organoaluminum compound in combination.

  The component (c) used in the coordination polymerization is a compound having a hydrolyzable halogen or a complex compound thereof with a Lewis base; an organic halide having a tertiary alkyl halide, benzyl halide or allyl halide; a non-coordinating anion And an ionic compound comprising a counter cation. Specific examples of the component (c) include alkylaluminum dichloride, dialkylaluminum chloride, silicon tetrachloride, tin tetrachloride, zinc chloride and Lewis base complexes such as alcohol, magnesium chloride and alcohol such as Lewis. Examples include complexes with bases, benzyl chloride, t-butyl chloride, benzyl bromide, t-butyl bromide, triphenylcarbonium tetrakis (pentafluorophenyl) borate and the like. These components (c) may be used alone or in combination of two or more.

  The polymerization initiator is preliminarily used by using the same conjugated diene compound and / or non-conjugated diene compound as the polymerization monomer, if necessary, in addition to the components (a), (b) and (c). May be prepared. Further, part or all of the component (a) or the component (c) may be supported on an inert solid. Although the usage-amount of said each component can be set suitably, (a) component is 0.001-0.5 millimoles (mmol) per 100g of monomers normally. In addition, (b) component / (b) component is preferably 5 to 1,000, and (c) component / (b) component is preferably 0.5 to 10 in molar ratio.

The polymerization temperature in the coordination polymerization is preferably in the range of −80 to 150 ° C., and more preferably in the range of −20 to 120 ° C. Moreover, as a solvent used for coordination polymerization, a hydrocarbon solvent inert to the reaction exemplified in the above-mentioned anionic polymerization can be used, and the concentration of the monomer in the reaction solution is the same as in the case of anionic polymerization. . Furthermore, the reaction pressure in coordination polymerization is the same as that in the case of anionic polymerization, and it is desirable that the raw material used for the reaction substantially removes reaction inhibitors such as water, oxygen, carbon dioxide, and protic compounds.
The modified conjugated diene polymer is preferably an anionic polymer using an organic alkali metal compound, particularly an alkyl lithium.

<Production of Modified Conjugated Diene Polymer>
(Modifier)
In the present invention, a primary amino group protected with a detachable group and / or 2 is used as a modifying agent to react with the active end of the conjugated diene polymer having an active end obtained as described above. A silane compound in which a secondary amino group-containing group and a hydrocarbyloxy group are bonded to the same silicon atom is preferably used.
Preferred examples of such a modifier include silane compounds selected from the following general formula (1), general formula (2), and general formula (3).

In the general formula (1), A ¹ is a halogen atom or a hydrocarbyloxy group having 1 to 20 carbon atoms, R ² is a hydrocarbon group R ³ is a hydrocarbon group, L ¹ is a detachable functional group, and L ² is When it is a detachable group or a hydrocarbon group, and L ² is a detachable functional group, it may have the same structure as L ¹ or a different structure, and L ¹ and L ² may be bonded. n represents 0 or 1, and m represents 1 or 2.
The hydrocarbon group represented by R ² is preferably a gate having 1 to 20 carbon atoms, and the hydrocarbon group represented by R ³ is preferably one having 1 to 12 carbon atoms.
In the general formula (2), R ⁴ is a hydrocarbon group having 1 to 20 carbon atoms, R ⁵ is a hydrocarbon group having 1 to 12 carbon atoms, A ² and A ³ are each independently a halogen atom or a carbon number 1 to 1 carbon atom. 20 hydrocarbyloxy groups, L ³ is a detachable functional group or hydrocarbon group, and L ⁴ is a detachable functional group. K represents 0 or 1, and f represents an integer of 1 to 10.
In the general formula (3), A ⁴ is a halogen atom or a hydrocarbyloxy group having 1 to 20 carbon atoms, R ⁶ is a hydrocarbon group having 1 to 20 carbon atoms, and R ⁷ is a hydrocarbon having 1 to 12 carbon atoms. Group, L ⁵ represents a detachable functional group or hydrocarbon group, and q represents ˜0 or 1.
Thus, N in the general formulas (1) to (3) has a form in which a primary amino group or a secondary amino group is protected with a detachable functional group.

In the general formulas (1) to (3), among A ^{1 to} A ⁴ , the halogen atom is preferably Cl, Br or I, and the hydrocarbyloxy group having 1 to 20 carbon atoms is carbon. It is preferable that it is a hydrocarbyloxy group of number 1-10. Examples of the hydrocarbyloxy group having 1 to 10 carbon atoms include an alkoxy group having 1 to 10 carbon atoms, an alkenyloxy group having 2 to 10 carbon atoms, an aryloxy group having 6 to 10 carbon atoms, and an aralkyloxy group having 7 to 10 carbon atoms. Among these, an alkoxy group having 1 to 10 carbon atoms is preferable from the viewpoint of having good reactivity. The alkyl group constituting the alkoxy group may be linear, branched or cyclic. Examples of such an alkoxy group include a methoxy group, an ethoxy group, an n-propoxy group, an isopropoxy group, an n-butoxy group, an isobutoxy group, a sec-butoxy group, a tert-butoxy group, various pentoxy groups, various hexoxy groups, Examples include various heptoxy groups, various octoxy groups, various decyloxy groups, cyclopetyloxy groups, cyclohexyloxy groups, and the like. Among these, alkoxy groups having 1 to 6 carbon atoms are preferable, and methoxy groups are particularly preferable. And ethoxy groups are preferred.

In the general formulas (1) to (3), examples of the hydrocarbon group having 1 to 20 carbon atoms represented by R ² , R ⁴ , and R ⁶ include an alkyl group having 1 to 18 carbon atoms and 2 to 2 carbon atoms. 18 alkenyl groups, aryl groups having 6 to 18 carbon atoms, aralkyl groups having 7 to 18 carbon atoms, and the like. Among these, from the viewpoint of the reactivity and performance of the modifier, those having 1 to 18 carbon atoms. An alkyl group is preferable, and an alkyl group having 1 to 10 carbon atoms is more preferable. The alkyl group may be linear, branched, or cyclic. For example, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, tert. -A butyl group, various pentyl groups, various hexyl groups, various octyl groups, various decyl groups, a cyclopentyl group, a cyclohexyl group, etc. can be mentioned. Among these, from the viewpoint of the reactivity and performance of the modifier, an alkyl group having 1 to 6 carbon atoms is preferable, and a methyl group is particularly preferable.

In the general formula (1) to (3), the R ^3, R ^5, and hydrocarbon group having 1 to 12 carbon atoms represented by R ^7, in view of the performance of modifier, from 1 to 12 carbon atoms Alkanediyl groups are more preferred, alkanediyl groups having 2 to 10 carbon atoms are more preferred, and alkanediyl groups having 2 to 6 carbon atoms are particularly preferred.
The alkanediyl group having 2 to 6 carbon atoms may be linear or branched. For example, ethylene group, 1,3-propanediyl group, 1,2-propanediyl group, various butanediyl groups, various types Examples thereof include a pentanediyl group and various hexanediyl groups, and among these, linear ones such as ethylene group, 1,3-propanediyl group, 1,4-butanediyl group, 1,5-pentanediyl group 1,6-hexanediyl group and the like, and 1,3-propanediyl group is particularly preferable.

In the general formula (1), L ¹ is a detachable functional group, and L ² is a detachable functional group or a hydrocarbon group. When L ² is a detachable functional group, it may be the same structure as L ¹ or a different structure, and L ¹ and L ² may be bonded.
In the general formula (2), L ³ is a detachable functional group or hydrocarbon group, and L ⁴ is a detachable functional group. In the general formula (3), L ⁵ is a detachable functional group or a hydrocarbon group.
Examples of the detachable functional group in L ^{1 to} L ⁴ include a trihydrocarbylsilyl group, preferably a trialkylsilyl group in which the hydrocarbyl group is an alkyl group having 1 to 10 carbon atoms. Particularly preferred is a trimethylsilyl group.
Examples of primary amino groups protected with a detachable group include N, N-bis (trimethylsilyl) amino group, and examples of secondary amino groups protected with a detachable group include N A-(trimethylsilyl) imino group can be mentioned.
The hydrocarbon group in L ^2, L ³ and L ^5, preferably a hydrocarbon group having 1 to 20 carbon atoms. For the hydrocarbon group of 1 to 20 carbon atoms is as indicated in the description of the aforementioned R ^2, R ⁴ and R ^6.

  In the present invention, as the silane compound represented by the general formula (1), a bifunctional hydrocarbyloxysilane compound in which m is 2 is preferable. By using such a bifunctional silane compound as a modifier, the resulting modified conjugated diene copolymer can introduce a highly efficient modified end and has an interaction with an inorganic filler such as silica. growing.

As a silane compound represented by the general formula (1), for example, when m has a primary amino group protected by 2 functional groups that can be eliminated, N, N-bis ( Trimethylsilyl) aminopropyl (methyl) dimethoxysilane, N, N-bis (trimethylsilyl) aminopropyl (methyl) diethoxysilane, N, N-bis (trimethylsilyl) aminopropyl (methyl) dipropoxysilane, N, N-bis ( Trimethylsilyl) aminopropyl (ethyl) dimethoxysilane, N, N-bis (trimethylsilyl) aminopropyl (ethyl) diethoxysilane, N, N-bis (trimethylsilyl) aminopropyl (ethyl) dipropoxysilane, N, N-bis ( Trimethylsilyl) aminoethyl (methyl) dimethoxysilane, N, N-bis Trimethylsilyl) aminoethyl (methyl) diethoxysilane, N, N-bis (trimethylsilyl) aminoethyl (methyl) dipropoxysilane, N, N-bis (trimethylsilyl) aminoethyl (ethyl) dimethoxysilane, N, N-bis ( Bifunctional alkoxysilane compounds such as trimethylsilyl) aminoethyl (ethyl) diethoxysilane, N, N-bis (trimethylsilyl) aminoethyl (ethyl) dipropoxysilane; N, N-bis (trimethylsilyl) aminopropyl (methyl) methoxychlorosilane N, N-bis (trimethylsilyl) aminopropyl (methyl) ethoxychlorosilane, N, N-bis (trimethylsilyl) aminoethyl (methyl) methoxychlorosilane, N, N-bis (trimethylsilyl) aminoethyl (meth) B) Bifunctional alkoxychlorosilane compounds such as ethoxychlorosilane; N, N-bis (trimethylsilyl) aminopropyl (methyl) dichlorosilane, N, N-bis (trimethylsilyl) aminopropyl (methyl) dichlorosilane, N, N-bis ( Bifunctional chlorosilane compounds such as trimethylsilyl) aminoethyl (methyl) dichlorosilane and N, N-bis (trimethylsilyl) aminoethyl (methyl) dichlorosilane can be exemplified.
Among these, N, N-bis (trimethylsilyl) aminopropyl (methyl) dimethoxysilane, N, N-bis (trimethylsilyl) aminopropyl (methyl) diethoxysilane and N, N-bis (trimethylsilyl) aminopropyl (methyl) ) Dipropoxysilane is preferred.

Further, the compound represented by the general formula (1) includes, for example, a case where m is 1 and L ² is a hydrocarbon group and has a secondary amino group protected by a detachable functional group. N-methyl-N-trimethylsilylaminopropyl (methyl) dimethoxysilane, N-methyl-N-trimethylsilylaminopropyl (methyl) diethoxysilane, N-ethyl-N-trimethylsilylaminopropyl (methyl) diethoxysilane, etc. Bifunctional alkoxysilane compounds and the like can be mentioned.

In the general formula (2), a bifunctional compound in which k is 1 is preferable for the same reason as in the general formula (1).
In the general formula (2), when f is 1, the silane compound represented by the general formula (2) is a detachable functional group 2 in the compound represented by the general formula (1). In the case of having a primary amino group protected by an individual and in the case of having a secondary amino group protected by one detachable functional group, the same compounds as the exemplified compounds can be exemplified.

In the general formula (3), a bifunctional silane compound in which q is 1 is preferable for the same reason as in the general formula (1).
Examples of the silane compound represented by the general formula (3) include 1-trimethylsilyl-2-ethoxy-2-methyl-1-aza-2-silacyclopentane, 1-trimethylsilyl-2-methoxy-2-methyl- 1-aza-2-silacyclopentane, 1-trimethylsilyl-2,2-diethoxy-1-aza-2-silacyclopentane, 1-trimethylsilyl-2,2-dimethoxy-1-aza-2-silacyclopentane, etc. Is mentioned.

The modifier in the present invention may be a compound having a primary amino group or secondary amino group-containing group protected with a detachable functional group and a silicon-containing hydrolyzable functional group, and the general formula ( It is not limited to the silane compounds represented by 1) to (3).
For example, (2,2,5,5-tetramethyl-1-aza-2,5-disilacyclopentan-1-yl) propyl (methyl) dimethoxysilane, (2,2,5,5-tetramethyl- 1-aza-2,5-disilacyclopentan-1-yl) propyl (methyl) diethoxysilane, N-trimethylsilyl (hexamethyleneimin-2-yl) propyl (methyl) dimethoxysilane, N-trimethylsilyl (Hexamethyleneimin-2-yl) propyl (methyl) diethoxysilane, N-trimethylsilyl (pyrrolidin-2-yl) propyl (methyl) dimethoxysilane, N-trimethylsilyl (pyrrolidin-2-yl) propyl (methyl) diethoxy Silane, N-trimethylsilyl (piperidin-2-yl) propyl (methyl) dimethoxy Lan, N-trimethylsilyl (piperidin-2-yl) propyl (methyl) diethoxysilane, N-trimethylsilyl (imidazol-2-yl) propyl (methyl) dimethoxysilane, N-trimethylsilyl (imidazol-2-yl) propyl (methyl) ) Diethoxysilane, N-trimethylsilyl (4,5-dihydroimidazol-5-yl) propyl (methyl) dimethoxysilane, N-trimethylsilyl (4,5-dihydroimidazol-5-yl) propyl (methyl) diethoxysilane, etc. Can also be used.

In the present invention, among the modifiers, in particular, N, N-bis (trimethylsilyl) aminopropyl (methyl) dimethoxysilane, N, N-bis (trimethylsilyl) aminopropyl (methyl) diethoxysilane, 1-trimethylsilyl 2-Ethoxy-2-methyl-1-aza-2-silacyclopentane is preferred.
These modifiers may be used alone or in combination of two or more.

《Condensation accelerator》
In this invention, in order to accelerate | stimulate the condensation reaction in which the silane compound used as the above-mentioned modifier is concerned, after performing a modification reaction, you may perform a condensation reaction in presence of a condensation accelerator as needed.
When the silane compound having a functional group is used as the primary modifier as described above, a secondary modification reaction is performed using a silane compound having the same or different functional group as the secondary modifier as necessary. be able to. Also in this case, the secondary modification reaction may be performed in the presence of a condensation accelerator as necessary.
As the condensation accelerator, a compound of an element belonging to at least one of Groups 4, 13, 14, and 15 of the periodic table is used.
As the condensation accelerator, at least one selected from a titanium compound, a tin compound, a zirconium compound, a bismuth compound, and an aluminum compound is preferably used, and more preferably, the alkoxide or carboxyl of each of the above elements. Acid salt and acetylacetonate complex salt, more preferably titanium alkoxide, titanium carboxylate, tin carboxylate, bismuth carboxylate, zirconium alkoxide, zirconium carboxylate, aluminum alkoxide and It is an aluminum carboxylate.

  As the condensation accelerator comprising a titanium compound, tetrakis (2-ethyl-1,3-hexanediolato) titanium, tetrakis (2-methyl-1,3-hexanediolato) titanium, tetrakis (2-propyl-1, 3-hexanediolato) titanium, tetrakis (2-butyl-1,3-hexanediolato) titanium, tetrakis (1,3-hexanediolato) titanium, tetrakis (1,3-pentanediolato) titanium, tetrakis ( 2-methyl-1,3-pentanediolato) titanium, tetrakis (2-ethyl-1,3-pentanediolato) titanium, tetrakis (2-propyl-1,3-pentanediolato) titanium, tetrakis (2- Butyl-1,3-pentanediolato) titanium, tetrakis (1,3-heptanediolato) titanium, tetrakis (2-methyl) -1,3-heptanediolato) titanium, tetrakis (2-ethyl-1,3-heptanediolato) titanium, tetrakis (2-propyl-1,3-heptanediolato) titanium, tetrakis (2-butyl-1,3-heptanediolato) titanium , Tetrakis (2-ethylhexoxy) titanium, tetramethoxy titanium, tetraethoxy titanium, tetra-n-propoxy titanium, tetraisopropoxy titanium, tetra-n-butoxy titanium, tetra-n-butoxy titanium oligomer, tetraisobutoxy titanium, tetra -Sec-butoxytitanium, tetra-tert-butoxytitanium, bis (oleate) bis (2-ethylhexanoate) titanium, titanium dipropoxybis (triethanolamate), titanium dibutoxybis (triethanolamino) ), Titanium tributoxy systemate, titanium tripropoxy systemate, titanium tripropoxyacetylacetonate, titanium dipropoxybis (acetylacetonate), titanium tripropoxy (ethylacetoacetate), titaniumpropoxyacetylacetonatebis (ethyl) Acetoacetate), titanium tributoxyacetylacetonate, titanium dibutoxybis (acetylacetonate), titanium tributoxyethylacetoacetate, titaniumbutoxyacetylacetonatebis (ethylacetoacetate), titanium tetrakis (acetylacetonate), titanium diacetyl Acetonate bis (ethyl acetoacetate), bis (2-ethylhexanoate) titanium oxide, bis (laurate) titanium oxide, bis (Naphthate) titanium oxide, bis (stearate) titanium oxide, bis (oleate) titanium oxide, bis (linoleate) titanium oxide, tetrakis (2-ethylhexanoate) titanium, tetrakis (laurate) titanium, tetrakis (naphthate) titanium , Tetrakis (stearate) titanium, tetrakis (oleate) titanium, tetrakis (linoleate) titanium, titanium di-n-butoxide (bis-2,4-pentanedionate), titanium oxide bis (tetramethylheptanedionate), titanium oxide Bis (pentanedionate), titanium tetra (lactate), etc. are mentioned. Among these, tetrakis (2-ethyl-1,3-hexanediolato) titanium, tetrakis (2-ethylhexoxy) titanium, and titanium di-n-butoxide (bis-2,4-pentanedionate) are preferable.

As the condensation accelerator made of a tin compound, for example, divalent tin carboxylate and tetravalent dihydrocarbyltin dicarboxylate can be preferably exemplified, and bis (2-ethylhexanoic acid) tin is particularly preferable. It is.
Examples of the condensation accelerator composed of a bismuth compound include tris (2-ethylhexanoate) bismuth, tris (laurate) bismuth, tris (naphthate) bismuth, tris (stearate) bismuth, tris (oleate) bismuth, tris ( Linoleate) bismuth. Of these, tris (2-ethylhexanoate) is preferred.

  Examples of the condensation accelerator composed of a zirconium compound include tetraethoxyzirconium, tetran-propoxyzirconium, tetraisopropoxyzirconium, tetran-butoxyzirconium, tetrasec-butoxyzirconium, tetratert-butoxyzirconium, tetra (2-ethylhexoxy). Zirconium, zirconium tributoxy systemate, zirconium tributoxyacetylacetonate, zirconium dibutoxybis (acetylacetonate), zirconium tributoxyethylacetoacetate, zirconiumbutoxyacetylacetonatebis (ethylacetoacetate), zirconium tetrakis (acetylacetonate) ), Zirconium diacetylacetonate bis (ethylacetoacetate) Bis (2-ethylhexanoate) zirconium oxide, bis (laurate) zirconium oxide, bis (naphthate) zirconium oxide, bis (stearate) zirconium oxide, bis (oleate) zirconium oxide, bis (linoleate) zirconium oxide, tetrakis ( Examples include 2-ethylhexanoate) zirconium, tetrakis (laurate) zirconium, tetrakis (naphthate) zirconium, tetrakis (stearate) zirconium, tetrakis (oleate) zirconium, tetrakis (linoleate) zirconium and the like. Among these, tetra n-propoxyzirconium, bis (2-ethylhexanoate) zirconium oxide, bis (oleate) zirconium oxide, and zirconium tetrakis (acetylacetonate) are preferable.

Examples of the condensation accelerator composed of an aluminum compound include triethoxyaluminum, tri-n-propoxyaluminum, triisopropoxyaluminum, tri-n-butoxyaluminum, trisec-butoxyaluminum, tritert-butoxyaluminum, tri (2-ethylhexoxy) Aluminum, aluminum dibutoxy systemate, aluminum dibutoxyacetylacetonate, aluminum butoxybis (acetylacetonate), aluminum dibutoxyethylacetoacetate, aluminum tris (acetylacetonate), aluminum tris (ethylacetoacetate), tris (2 -Ethylhexanoate) aluminum, tris (laurate) aluminum, tris (naphthate) aluminum, Squirrel (stearate) aluminum, tris (oleate) aluminum, and tris (linolate) aluminum.
Among these, triisopropoxyaluminum, trisec-butoxyaluminum, tris (2-ethylhexanoate) aluminum, tris (stearate) aluminum, and aluminum tris (acetylacetonate) are preferable.

The amount of the condensation accelerator used is preferably such that the number of moles of the above compound is 0.1 to 10 as the molar ratio to the total amount of functional groups bonded to silicon atoms present in the reaction system. ~ 5 is particularly preferred. By setting the use amount of the condensation accelerator within the above range, the condensation reaction proceeds efficiently.
The addition time of the condensation accelerator is usually 5 minutes to 5 hours after the start of the modification reaction, preferably 15 minutes to 1 hour after the start of the modification reaction.
The condensation reaction in the present invention is preferably carried out in the presence of water. As the water, a form such as a simple substance, a solution of alcohol or the like, a dispersed micelle in a hydrocarbon solvent, etc. are suitably used. Water that is potentially contained in a compound capable of releasing water in the reaction system, such as water adsorbed in water and hydrated water of hydrates, can also be used effectively. Accordingly, it is also preferable to use a compound that can easily release water, such as a solid having adsorbed water or a hydrate, in combination with the metal compound.
The two of the condensation accelerator and water may be added separately to the reaction system or mixed immediately before use as a mixture, but long-term storage of the mixture is preferable because it causes decomposition of the condensation accelerator. Absent.
The molar ratio between the condensation accelerator and water effective for the reaction varies depending on the required reaction conditions, but is preferably about 1 / 0.5 to 1/20.

Moreover, it is preferable to perform reaction using this condensation accelerator at the temperature of 20 degreeC or more, Furthermore, the range of 30-120 degreeC is preferable. The reaction time is preferably about 0.5 to 120 minutes, more preferably 3 to 60 minutes.
The pressure of the reaction system during the condensation reaction is usually 0.01 to 20 MPa, preferably 0.05 to 10 MPa.
There is no restriction | limiting in particular about the form of a condensation reaction, You may carry out by a continuous type using apparatuses, such as a batch type reactor and a multistage continuous reactor. Moreover, you may perform this condensation reaction and a desolvent simultaneously.
In addition, when the silane compound which has a protected amino group is used as a modifier, it can convert into the free amino group by hydrolyzing the silyl protecting group in this protected amino group. By removing the solvent from this, a dried polymer having a protic amino group is obtained. In addition, the deprotection treatment of the protective amino group derived from the modifier can be performed as necessary in any stage from the stage including the condensation treatment to the solvent removal to the dry polymer.

The modified conjugated diene polymer thus obtained preferably has a glass transition point (Tg) of 10 ° C. or lower. This is because if Tg is 10 ° C. or lower, the rolling resistance can be further reduced and the flexibility of the rubber composition at low temperatures can be increased.
The Mooney viscosity (ML _{1 + 4} , 100 ° C.) of the modified conjugated diene polymer is preferably 10 to 150, more preferably _{15 to} 100. By setting the Mooney viscosity value within the above range, a rubber composition having excellent kneading workability and mechanical properties after vulcanization can be obtained.

(Optional rubber component)
In the rubber composition of the present invention, it is necessary that (A) the rubber component contains 10% by mass or more of the modified conjugated diene polymer described above.
(A) By setting the modified conjugated diene polymer in the rubber component to 10% by mass or more, a rubber composition having desired physical properties can be obtained. The preferable content of the modified conjugated diene polymer in the rubber component is 30% by mass or more, and particularly preferably 40% by mass or more.
One kind of this modified conjugated diene polymer may be used, or two or more kinds may be used in combination. Other rubber components used in combination with this modified conjugated diene polymer include natural rubber, synthetic isoprene rubber, butadiene rubber, styrene-butadiene rubber, ethylene-α-olefin copolymer rubber, and ethylene-α-olefin. Examples thereof include at least one selected from diene copolymer rubber, chlorobrene rubber, halogenated butyl rubber, and a copolymer of styrene and isobutylene having a halogenated methyl group.
In the present invention, it is preferable to use natural rubber and / or synthetic isoprene rubber as the other rubber component.

[(B) Reinforcing filler]
As the reinforcing filler (B) in the rubber composition of the present invention, carbon black and / or silica can be used.
Carbon black is not particularly limited, and for example, SRF, GPF, FEF, HAF, 1SAF, SAF, etc. are used, iodine adsorption amount (IA) is 60 mg / g or more, and dibutyl phthalate oil absorption amount (DBP) is 80 ml / 100 g. The above carbon black is preferable. By using carbon black, the effect of improving grip performance and fracture resistance is increased, but HAF, ISAF, and SAF, which are excellent in wear resistance, are particularly preferable.
On the other hand, the silica is not particularly limited, and can be arbitrarily selected from those conventionally used as reinforcing fillers for rubber.
Examples of the silica include wet silica (hydrous silicic acid), dry silica (anhydrous silicic acid), calcium silicate, aluminum silicate, and the like. Wet silica that is noticeable is preferred.

In the present invention, as the (B) reinforcing filler, only carbon black may be used, silica alone may be used, or carbon black and silica may be used in combination. The reinforcing filler needs to be blended in an amount of 20 parts by mass or more with respect to 100 parts by mass of the (A) rubber component. If the amount is less than 20 parts by mass, the reinforcing effect is not sufficiently exhibited.
Silica and / or carbon black is preferably blended in an amount of 20 to 120 parts by mass with respect to 100 parts by mass of (A) rubber component. Part by mass is more preferable. By setting the amount of carbon black and / or silica within the above range, factory workability such as kneading workability is excellent, and desired fracture characteristics can be obtained as a rubber composition.
In the case of silica alone, the compounding amount of silica is preferably 50 parts by mass or more and more preferably 55 to 80 parts by mass with respect to 100 parts by mass of the (A) rubber component.

(Silane coupling agent)
In the rubber composition of the present invention, when silica is used as the reinforcing filler, a silane coupling agent can be blended for the purpose of further improving the reinforcing property and low exothermic property.
Examples of the silane coupling agent include bis (3-triethoxysilylpropyl) tetrasulfide, bis (3-triethoxysilylpropyl) trisulfide, bis (3-triethoxysilylpropyl) disulfide, and bis (2-sodium trisulfide). Ethoxysilylethyl) tetrasulfide, bis (3-trimethoxysilylpropyl) tetrasulfide, bis (2-trimethoxysilylethyl) tetrasulfide, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, 2-mercapto Ethyltrimethoxysilane, 2-mercaptoethyltriethoxysilane, 3-trimethoxysilylpropyl-N, N-dimethylthiocarbamoyl tetrasulfide, 3-triethoxysilylpropyl-N, N-dimethylthioca Vamoyl tetrasulfide, 2-triethoxysilylethyl-N, N-dimethylthiocarbamoyl tetrasulfide, 3-trimethoxysilylpropylbenzothiazolyl tetrasulfide, 3-triethoxysilylpropylbenzothiazolyl tetrasulfide, 3- Triethoxysilylpropyl methacrylate monosulfide, 3-trimethoxysilylpropyl methacrylate monosulfide, bis (3-diethoxymethylsilylpropyl) tetrasulfide, 3-mercaptopropyldimethoxymethylsilane, dimethoxymethylsilylpropyl-N, N-dimethylthio Carbamoyl tetrasulfide, dimethoxymethylsilylpropylbenzothiazolyl tetrasulfide, and the like can be mentioned. Among these, from the viewpoint of reinforcing effect, Scan (3-triethoxysilylpropyl) polysulfide and 3-trimethoxysilylpropyl benzothiazolyl tetrasulfide are preferable.
One of these silane coupling agents may be used alone, or two or more thereof may be used in combination.

  In the rubber composition of the present invention, the compounding amount of the silane coupling agent varies depending on the type of the silane coupling agent and the like, but is preferably selected in the range of 1 to 20% by mass with respect to silica. If this amount is less than 1% by mass, the effect as a coupling agent is hardly exhibited, and if it exceeds 20% by mass, the rubber component may be gelled. From the viewpoints of the effect as a coupling agent and the prevention of gelation, a more preferable blending amount of this silane coupling agent is in the range of 5 to 15% by mass.

[(C) Unmodified and / or Modified Low Molecular Weight Conjugated Diene Polymer]
In the rubber composition of the present invention, an unmodified and / or modified low molecular weight conjugated diene polymer having the following properties is blended as the component (C).
In the present invention, the unmodified and / or modified low molecular weight conjugated diene polymer of component (C) is preferably an unmodified and / or aromatic vinyl compound-conjugated diene compound copolymer. (Hereafter, it may be abbreviated as “unmodified and / or modified low molecular weight diene copolymer”.)
This low molecular weight conjugated diene copolymer may be only unmodified or may contain 10% by mass or more of a modified product having at least one functional group.
Conventional softeners such as aroma oil have a relatively high polarity, and thus have a high affinity for a modified conjugated diene polymer having a functional group. Therefore, the modified conjugated diene polymer is trapped by a softening agent such as aroma oil during the kneading of the rubber composition, and the effect of improving the dispersibility of the (B) reinforcing filler is impaired. In contrast, the (C) unmodified and / or modified low molecular weight diene copolymer used in the present invention does not trap the modified conjugated diene polymer during kneading, and is based on the modified conjugated diene polymer ( B) The effect of improving the dispersibility of the reinforcing filler can be sufficiently exhibited, and the workability, fracture characteristics, wear resistance and low heat build-up of the rubber composition can be sufficiently improved.

(Properties of unmodified low molecular weight diene copolymer)
In the rubber composition of the present invention, the unmodified and / or modified low molecular weight diene copolymer of the component (C) is an unmodified product or a property before modification, and the content of the aromatic vinyl compound unit is 5 to 5. A low molecular weight diene copolymer having a weight average molecular weight of 5,000 to 300,000 and a weight average molecular weight of 5,000 to 300,000 is 80% by mass and the vinyl bond content of the conjugated diene moiety is 10 to 80% by mass. It is necessary to contain 5 to 60 parts by mass with respect to 100 parts by mass of the component, preferably 15 to 60 parts by mass, and more preferably 20 to 60 parts by mass. If content of the said (C) component is less than 5 mass parts, the workability | operativity of a rubber composition will deteriorate.
The low molecular weight diene copolymer of the component (C) is an unmodified product or a property before modification, and the vinyl bond amount of the conjugated diene compound portion is required to be 10 to 80% by mass. When the vinyl bond amount of the conjugated diene compound portion is less than 10% by mass or more than 80% by mass, it is not possible to sufficiently achieve both workability of the rubber composition and reduction of the loss tangent (tan δ) of the rubber composition. . Furthermore, the weight average molecular weight is 5,000 to 300,000, preferably 20,000 to 200,000, and more preferably 30,000 to 150,000. When the weight average molecular weight is less than 5,000, the storage elastic modulus (G ′) of the rubber composition tends to decrease and the loss tangent (tan δ) of the rubber composition tends to increase, whereas when it exceeds 300,000. The workability of the rubber composition is reduced.
In addition, the said weight average molecular weight is the value of polystyrene conversion measured by the gel permeation chromatography method (GPC method).

(Production of unmodified low molecular weight diene copolymer)
An unmodified low molecular weight diene copolymer is obtained by copolymerizing an aromatic vinyl compound and a conjugated diene compound, which are monomers, using a polymerization initiator. Here, examples of the aromatic vinyl compound include styrene, p-methylstyrene, m-methylstyrene, p-tert-butylstyrene, α-methylstyrene, chloromethylstyrene, vinyltoluene, and the like. Among these, styrene Is preferred. On the other hand, examples of the conjugated diene compound include 1,3-butadiene, isoprene, 1,3-pentadiene, 2,3-dimethylbutadiene, and among these, 1,3-butadiene is preferable.

  This unmodified low molecular weight diene copolymer is preferably produced by anionic polymerization using an organic alkali metal compound as a polymerization initiator, and is the same as the above-described production by anionic polymerization of a modified conjugated diene polymer. Thus, the amount of the monomer used and the amount of the polymerization initiator used can be adjusted as appropriate. In addition, it is preferable that the said copolymer is manufactured by solution polymerization, and since the said copolymer is 5-80 mass% of aromatic vinyl compounds, it is the conjugated diene compound in a polymerization reaction solution, and The content of the aromatic vinyl compound in the total amount with the aromatic vinyl compound is preferably in the range of 5 to 80% by mass.

(Modified low molecular weight diene copolymer)
In the present invention, as an unmodified and / or modified low molecular weight diene copolymer of component (C), a modified product having at least one functional group is 10% by mass or more, preferably 15% by mass or more, more preferably It is desirable to use those containing 20% by mass or more from the viewpoint of better exhibiting the effects of the present invention.
The modified low molecular weight diene copolymer is (1) an aromatic vinyl compound and a conjugated diene compound, which are monomers, are copolymerized using a polymerization initiator to have an active terminal and the above-mentioned aromatic properties. After producing a vinyl compound-conjugated diene compound copolymer, a method of modifying the active terminal with various modifiers, and (2) having a functional group of a monomeric aromatic vinyl compound and a conjugated diene compound It can be obtained by a method of copolymerization using a polymerization initiator.
As a polymerization initiator used for manufacture of a modified low molecular weight diene copolymer, an organic alkali metal compound is preferable, and a lithium compound is more preferable. Examples of the lithium compound include hydrocarbyl lithium and lithium compounds listed as the polymerization initiator used for the production of the conjugated diene polymer described above. Here, when the above-described hydrocarbyl lithium is used as a polymerization initiator, a copolymer having a hydrocarbyl group at the polymerization initiation terminal and the other terminal being a polymerization active site is obtained. Further, when the above-mentioned lithium amide compound is used as a polymerization initiator, a copolymer having a nitrogen-containing functional group at the polymerization initiation terminal and the other terminal being a polymerization active site is obtained. Even if it is not modified with an agent, it has at least one functional group.

In the modified low molecular weight diene copolymer used in the present invention, the functional group is preferably a functional group containing nitrogen, and the functional group containing nitrogen is protected with a primary amino group or a detachable group. Further, primary amino group, substituted amino group, amide group, imino group, imidazole residue, nitrile group, pyridyl group and the like can be mentioned.
Examples of the detachable group formed by protecting the primary amino group include a trimethylsilyl group and 2,2,5,5-tetramethyl- (1-aza-2,5-disilacyclopentane) -1 -An yl group etc. can be mentioned.
Furthermore, as a functional group containing nitrogen, the following general formula (4)

[Wherein, R ⁸ and R ⁹ each independently represents an alkyl group having 1 to 12 carbon atoms, a cycloalkyl group having 3 to 12 carbon atoms, or an aralkyl group having 7 to 12 carbon atoms. ]
A substituted amino group represented by general formula (5):

[Wherein, R ¹⁰ represents an alkylene group having 3 to 16 methylene groups, a substituted alkylene group, an oxyalkylene group or an N-alkylaminoalkylene group. ]
And a group selected from cyclic amino groups represented by the formula:
Specific examples of R ⁸ and R ⁹ in the general formula (4) include a methyl group, an ethyl group, a butyl group, an octyl group, a cyclohexyl group, a 3-phenyl-1-propyl group and an isobutyl group. R ⁸ and R ⁹ may be the same or different.
In the general formula (5), the substituted alkylene group in R ¹⁰ includes a mono- to octa-substituted alkylene group, and the substituent is a linear or branched alkyl group having 1 to 12 carbon atoms. Cycloalkyl group, bicycloalkyl group, aryl group and aralkyl group. R ¹⁰ is specifically preferably a trimethylene group, a tetramethylene group, a hexamethylene group, an oxydiethylene group, an N-alkylazadiethylene group, a dodecamethylene group, a hexadecamethylene group, or the like.
These functional groups containing nitrogen are represented by the following general formula (9) as a polymerization initiator.
Li-AM (9)
[Wherein, AM represents a substituted amino group represented by the general formula (4) or a cyclic amino group represented by the general formula (5). ]
An anionic vinyl compound and a conjugated diene compound are subjected to anionic polymerization using a lithium amide compound represented by the following formula, and the substituted amino group represented by the above general formula (4) or the general formula A modified low molecular weight diene copolymer into which the cyclic amino group represented by (5) is introduced is obtained.

(Modifier)
The modified product of the low molecular weight diene copolymer used in the present invention can also be produced by reacting the active terminal of the low molecular weight diene copolymer having an active terminal with an appropriate modifier and performing a modification reaction. be able to.
Here, the low molecular weight diene copolymer having an active end is an aromatic organic metal compound, preferably a lithium compound, as described in the production of the modified conjugated diene polymer in the component (A). An aromatic vinyl compound and a conjugated diene compound can be obtained by anionic polymerization in the same manner as described above. In this case, the reaction conditions are appropriately selected so that the resulting low molecular weight diene copolymer having an active terminal has the above-described properties.
Nitrogen-containing compounds, silicon-containing compounds, tin-containing compounds, and the like can be used as modifiers to be reacted with the active terminals of the low molecular weight diene copolymer thus obtained.
Nitrogen-containing compounds that can be used as the modifier include bis (diethylamino) benzophenone, dimethylimidazolidinone, N-methylpyrrolidone, 4-dimethylaminobenzylideneaniline, and the like. By using these nitrogen-containing compounds as modifiers, functional groups containing nitrogen such as substituted and unsubstituted amino groups, amide groups, imino groups, imidazole residues, nitrile groups, and pyridyl groups can be introduced.
In the modification reaction of the present invention, it is preferable that the low molecular weight diene copolymer having an active terminal to be used has at least 10% of polymer chains having a living property.

  The silicon-containing compound that can be used as the modifier is preferably a hydrocarbyloxysilane compound. For example, the following general formula (6)

[In the formula, A ⁵ represents (thio) epoxy group, (thio) isocyanate group, (thio) carbonyl group, (thio) formyl group, imine residue, amide group, isocyanuric acid triester residue, (thio) carboxyl One having at least one functional group selected from an acid hydrocarbyl ester residue, a metal salt residue of (thio) carboxylic acid, a carboxylic acid anhydride residue, a carboxylic acid halide residue, and a carbonic acid dihydrocarbyl ester residue A valent group, R ¹¹ and R ¹² are each independently a monovalent aliphatic hydrocarbon group having 1 to 20 carbon atoms or a monovalent aromatic hydrocarbon group having 6 to 18 carbon atoms, and R ¹³ is a single bond or carbon. indicates the number of 1 to 20 divalent inert hydrocarbon group, n is an integer of 1 to 3, if the OR ¹¹ there are multiple to a plurality of OR ¹¹ may be the same or different, R ¹² is If there are multiple, multiple R ¹² It may be the same or different, do not include active proton and onium salt in the molecule. ]
And a partial condensate thereof, and the general formula (7)
R ¹⁴ _p -Si- (OR ¹⁵ ) _4-p (7)
[Wherein, R ¹⁴ and R ¹⁵ each independently represent a monovalent aliphatic hydrocarbon group having 1 to 20 carbon atoms or a monovalent aromatic hydrocarbon group having 6 to 18 carbon atoms; an integer 2, if the OR ¹⁵ there are multiple to a plurality of OR ¹⁵ may be the same or different, if R ¹⁴ is plural, R ¹⁴ may be the same or different in the molecule Does not include active protons and onium salts. ]
More preferred is at least one selected from the hydrocarbyloxysilane compounds represented by the formula (1) and partial condensates thereof.

In the general formula (6), among the functional groups in A ⁵ , the imine residue includes ketimine, aldimine and amidine residues, and the (thio) carboxylic acid hydrocarbyl ester is an unsaturated carboxylic acid such as acrylate or methacrylate. Includes ester residues. Examples of the metal of the metal salt residue of (thio) carboxylic acid include alkali metals, alkaline earth metals, aluminum, tin, and zinc.

Examples of R ¹¹ and R ¹² include an alkyl group having 1 to 20 carbon atoms, an alkenyl group having 2 to 18 carbon atoms, an aryl group having 6 to 18 carbon atoms, and an aralkyl group having 7 to 18 carbon atoms. Here, the alkyl group and alkenyl group may be linear, branched, or cyclic, for example, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group. , Sec-butyl, tert-butyl, pentyl, hexyl, octyl, decyl, dodecyl, cyclopentyl, cyclohexyl, vinyl, propenyl, allyl, hexenyl, octenyl, cyclo A pentenyl group, a cyclohexenyl group, etc. are mentioned. The aryl group may have a substituent such as a lower alkyl group on the aromatic ring, and examples thereof include a phenyl group, a tolyl group, a xylyl group, and a naphthyl group. Furthermore, the aralkyl group may have a substituent such as a lower alkyl group on the aromatic ring, and examples thereof include a benzyl group, a phenethyl group, and a naphthylmethyl group.

The divalent inert hydrocarbon group having 1 to 20 carbon atoms in R ¹³ is preferably an alkylene group having 1 to 20 carbon atoms. The alkylene group may be linear, branched or cyclic, but a linear one is particularly preferable. Examples of the linear alkylene group include a methylene group, an ethylene group, a trimethylene group, a tetramethylene group, a pentamethylene group, a hexamethylene group, an octamethylene group, a decamethylene group, and a dodecamethylene group.
N is an integer of 1 to 3, but 3 is preferable. When n is 2 or 3, each R ⁶ O may be the same or different. When n is 1, two R ⁷ may be the same or different.

  Examples of the hydrocarbyloxysilane compound represented by the general formula (6) include (thio) epoxy group-containing hydrocarbyloxysilane compounds such as 2-glycidoxyethyltrimethoxysilane, 2-glycidoxyethyltriethoxysilane, (2-glycidoxyethyl) methyldimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, (3-glycidoxypropyl) methyldimethoxysilane, 2- (3,4 -Epoxycyclohexyl) ethyltrimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltriethoxysilane, 2- (3,4-epoxycyclohexyl) ethyl (methyl) dimethoxysilane, and thioepoxy groups in these compounds Replace with There may be mentioned a was, among these, 3-glycidoxypropyltrimethoxysilane and 3-glycidoxypropyl triethoxysilane are particularly preferred.

  Further, as the imine residue-containing hydrocarbyloxysilane compound, N- (1,3-dimethylbutylidene) -3- (triethoxysilyl) -1-propanamine, N- (1-methylethylidene) -3- (tri Ethoxysilyl) -1-propanamine, N-ethylidene-3- (triethoxysilyl) -1-propanamine, N- (1-methylpropylidene) -3- (triethoxysilyl) -1-propanamine, N -(4-N, N-dimethylaminobenzylidene) -3- (triethoxysilyl) -1-propanamine, N- (cyclohexylidene) -3- (triethoxysilyl) -1-propanamine and their tris Trimethoxysilyl compounds, methyldiethoxysilyl compounds, ethyldiethoxysilyl compounds corresponding to ethoxysilyl compounds Examples thereof include a methyldimethoxysilyl compound and an ethyldimethoxysilyl compound. Among these, N- (1-methylpropylidene) -3- (triethoxysilyl) -1-propanamine and N- (1,3 -Dimethylbutylidene) -3- (triethoxysilyl) -1-propanamine is particularly preferred.

  Examples of the imine (amidine) residue-containing compound include 1- [3- (triethoxysilyl) propyl] -4,5-dihydroimidazole, 1- [3- (trimethoxysilyl) propyl] -4,5- Dihydroimidazole, N- (3-triethoxysilylpropyl) -4,5-dihydroimidazole, N- (3-isopropoxysilylpropyl) -4,5-dihydroimidazole, N- (3-methyldiethoxysilylpropyl) Examples include -4,5-dihydroimidazole, and among these, N- (3-triethoxysilylpropyl) -4,5-dihydroimidazole is preferable.

  Furthermore, the following can be mentioned as another hydrocarbyl oxysilane compound. That is, examples of the carboxylic acid hydrocarbyl ester residue-containing compound include 3-methacryloyloxypropyltriethoxysilane, 3-methacryloyloxypropyltrimethoxysilane, 3-methacryloyloxypropylmethyldiethoxysilane, and 3-methacryloyloxypropyl. Examples include triisopropoxysilane, among which 3-methacryloyloxypropyltrimethoxysilane is preferable.

  Examples of the isocyanate group-containing compound include 3-isocyanatopropyltrimethoxysilane, 3-isocyanatopropyltriethoxysilane, 3-isocyanatopropylmethyldiethoxysilane, and 3-isocyanatopropyltriisopropoxysilane. Among these, 3-isocyanatopropyltriethoxysilane is preferable.

  Further, as carboxylic acid anhydride residues, 3-triethoxysilylpropyl succinic anhydride residue, 3-trimethoxysilylpropyl succinic anhydride residue, 3-methyldiethoxysilylpropyl succinic anhydride residue Among them, 3-triethoxysilylpropyl succinic anhydride residue is preferable among these.

On the other hand, in the general formula (7), R ¹⁴ and R ¹⁵ are as described for R ¹¹ and R ¹² in the general formula (6), respectively.
Examples of the hydrocarbyloxysilane compound represented by the general formula (7) include tetramethoxysilane, tetraethoxysilane, tetra-n-propoxysilane, tetraisopropoxysilane, tetra-n-butoxysilane, tetraisobutoxysilane, Tetra-sec-butoxysilane, tetra-tert-butoxysilane, methyltrimethoxysilane, methyltriethoxysilane, methyltripropoxysilane, methyltriisopropoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, propyltriethoxysilane, Butyltrimethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, dimethyldimethoxysilane, methylphenyldimethoxysilane, vinyltrimethoxysilane, vinyltriet Shishiran, divinyl dimethoxysilane, divinyl diethoxy silane and the like, and among them, tetraethoxysilane is particularly preferred.
One of these hydrocarbyloxysilane compounds may be used alone, or two or more thereof may be used in combination. Moreover, the partial condensate of the said hydrocarbyl oxysilane compound can also be used.

As the modifier, the following general formula (8)
R ¹⁶ _a ZX _b (8)
[Wherein R ¹⁶ is an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 3 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms or an aralkyl group having 7 to 20 carbon atoms, and Z is a tin atom or silicon. atom, X is shows a chlorine atom or a bromine atom, a is 0 to 3, b is 1 to 4, if R ¹⁶ have multiple to a plurality of R ¹⁶ may be the same or different, X is more In some cases, multiple Xs may be the same or different and a + b = 4. ]
A coupling agent represented by the formula can also be used. The low molecular weight diene copolymer modified with the coupling agent of the general formula (6) has at least one tin carbon bond or silicon-carbon bond. In the general formula (8), specific examples of R ¹⁶ include a methyl group, an ethyl group, an n-butyl group, a neopentyl group, a cyclohexyl group, an n-octyl group, and a 2-ethylhexyl group.
As the coupling agent of the general formula (6), for example, tin tetrachloride, R ¹⁶ SnCl ₃ , R ¹⁶ ₂ SnCl ₂ , R ¹⁶ ₃ SnCl and the like are preferable, and tin tetrachloride is particularly preferable.

  The modification reaction with the modifying agent is preferably performed by a solution reaction, and the solution may contain a monomer used during polymerization. The reaction mode of the modification reaction is not particularly limited, and may be a batch type or a continuous type. Furthermore, the reaction temperature of the modification reaction is not particularly limited as long as the reaction proceeds, and the reaction temperature of the polymerization reaction may be employed as it is. In addition, the usage-amount of modifier | denaturant has the preferable range of 0.25-3.0 mol with respect to 1 mol of polymerization initiators used for manufacture of a low molecular weight diene-type copolymer, and the range of 0.5-1.5 mol. Further preferred.

In the present invention, in order to accelerate the condensation reaction involving the alkoxysilane compound used as the modifier, the condensation reaction may be performed in the presence of a condensation accelerator as necessary after the modification reaction. .
Moreover, when an alkoxysilane compound is used as a primary modifier as described above, a secondary modification reaction can be performed using the same or different alkoxysilane compound as a secondary modifier, if necessary. Also in this case, the secondary modification reaction may be performed in the presence of a condensation accelerator as necessary.
The type of condensation accelerator, the condensation reaction conditions, and the like are as described in the production of the modified conjugated diene polymer in the component (A).

  The functional group in the modified low molecular weight diene copolymer of component (C) thus obtained preferably has an interaction with the reinforcing filler of component (B). When the functional group interacts with the reinforcing filler, the dispersibility of the reinforcing filler in the rubber composition is improved, and the workability, fracture characteristics, wear resistance and low resistance of the rubber composition are improved. Exotherm is improved reliably.

[Preparation and use of rubber composition]
In the rubber composition of the present invention, various chemicals usually used in the rubber industry, for example, a vulcanizing agent, a vulcanization accelerator, an anti-aging agent, an anti-scorch agent, as long as the purpose of the present invention is not impaired. An agent, zinc white, stearic acid and the like can be contained.
Further, the rubber composition of the present invention is obtained by kneading using a kneader such as an open kneader such as a roll, a closed kneader such as a Banbury mixer, and vulcanized after molding. Applicable to various rubber products. For example, it can be used for tire applications such as tire treads, base treads, carcass, sidewalls, beads and inner liner parts, vibration proof rubber, fenders, belts, hoses and other industrial products. In particular, it is suitably used as a tread rubber for low fuel consumption tires, large tires, and high performance tires, which have an excellent balance of low heat generation, wear resistance, and breaking strength.

[tire]
The tire of the present invention is characterized by using the above-described rubber composition of the present invention for a tire member. As the tire member, a tread, a base tread, and a sidewall can be preferably mentioned, and the rubber composition of the present invention can be used for any of these, and it is particularly preferable to use for a tread.
A tire using the rubber composition of the present invention for a tread has low rolling resistance and excellent fuel efficiency, and excellent fracture characteristics and wear resistance. In addition, as gas with which the tire of the present invention is filled, normal or air with a changed oxygen partial pressure, or an inert gas such as nitrogen is exemplified. When the rubber composition of the present invention is used for a tread, for example, it is extruded on a tread member, and is pasted and molded by a usual method on a tire molding machine to form a raw tire. The green tire is heated and pressed in a vulcanizer to obtain a tire.

Hereinafter, the present invention will be described in more detail with reference to examples. However, the present invention is not limited to the following examples.
In addition, the loss tangent (tan δ) and wear resistance of the rubber composition after vulcanization, the bonded styrene content, the microstructure (vinyl bond content) of the unmodified / modified SBR, the number average molecular weight, the weight average molecular weight, and the unmodified The bound styrene content, microstructure (vinyl bond content), and weight average molecular weight before modification of the modified low molecular weight SBR were determined by the following methods.
<Rubber composition after vulcanization>
(1) Loss tangent (tan δ)
Using a viscoelasticity measuring device manufactured by Rheometrics, tan δ was measured at a temperature of 50 ° C., a frequency of 15 Hz, and a strain of 5%. tan δ indicates that the lower the index value, the better the low heat build-up.
(2) Abrasion resistance Using a Ramborn-type abrasion tester, the amount of abrasion with a slip rate of 25% at room temperature was measured, and the reciprocal of the amount of abrasion of the control was represented as an index. It shows that it is excellent in abrasion resistance, so that an index | exponent is large.
<Non-modified / modified SBR, Unmodified / modified low molecular weight SBR>
(3) Microstructure and bound styrene content The microstructure of the polymer was determined by the infrared method (Morero method), and the bound styrene content of the polymer was determined from the integral ratio of the ¹ H-NMR spectrum.
(4) Number average molecular weight (Mn) and weight average molecular weight (Mw)
Gel permeation chromatography [GPC: Tosoh HLC-8020, column: Tosoh GMH-XL (two in series), detector: differential refractometer (RI)] The Mn and Mw of the modified SBR were determined, and the Mw before the modification of the unmodified / modified low molecular weight SBR was determined.

Production Example 1 Production of Unmodified SBR To an 800 mL pressure-resistant glass container that has been dried and purged with nitrogen, 300 g of cyclohexane, 40 g of 1,3-butadiene, 10 g of styrene, 0.2 mmol of ditetrahydrofurylpropane, and n-butyllithium 0 After adding 0.4 mmol, a polymerization reaction was carried out at 50 ° C. for 1.5 hours. The polymerization conversion rate at this time was almost 100%. Thereafter, 0.5 mL of an isopropanol solution (concentration: 5% by mass) of 2,6-di-t-butyl-p-cresol is added to the polymerization reaction system to stop the polymerization reaction, and further dried according to a conventional method. Unmodified SBR was obtained. Table 1 shows the bound styrene content of the unmodified SBR and the bound vinyl content of the butadiene part, and Mn and Mw.

Production Example 2 Production of Modified SBR A <Production of SBR with Active End>
After adding 300 g of cyclohexane, 40 g of 1,3-butadiene, 10 g of styrene, 0.2 mmol of ditetrahydrofurylpropane, and further adding 0.48 mmol of n-butyllithium to an 800 mL pressure-resistant glass container that has been dried and purged with nitrogen, The polymerization reaction was carried out at ° C for 1.5 hours. The polymerization conversion rate at this time was almost 100%.
<Modification reaction process>
Next, 0.43 mmol of modifier X (3-N, N-bis (trimethylsilyl) aminopropyl (methyl) diethoxysilane) was added to the polymerization reaction system, and a modification reaction was further performed at 50 ° C. for 30 minutes.
<Post-polymerization treatment>
Next, 2,6-di-tert-butyl-p-cresol in an isopropanol solution (concentration: 5% by mass) was added to the polymerization reaction system to stop the polymerization reaction. Thereafter, steam was blown to lower the solvent partial pressure (steam stripping) to remove the solvent, followed by vacuum drying to obtain modified SBR A. Table 1 shows the bound styrene content of the modified SBR A and the bound vinyl content of the butadiene moiety, and Mn and Mw.

Production Example 3 Production of Modified SBR B In the modification reaction step in Production Example 2, 0.43 mmol of modifier X was added, and after 15 minutes of denaturation reaction at 50 ° C., tetrakis (2-ethylhexyloxy) titanium 0.43 mmol In addition, modified SBR B was obtained in the same manner as in Production Example 2 except that the reaction was further performed at 50 ° C. for 15 minutes. Table 1 shows the bound styrene content of the modified SBR B obtained, the bound vinyl content of the butadiene moiety, and Mn and Mw.

Production Example 4 Production of Modified SBR C In the modification reaction step in Production Example 2, 0.43 mmol of modifier X was added and the modification reaction was performed at 50 ° C. for 15 minutes, followed by tetrakis (2-ethyl-1,3-hexane). Diolato) Modified SBR C was obtained in the same manner as in Production Example 2 except that 0.43 mmol of titanium was added and the reaction was further carried out at 50 ° C. for 15 minutes. Table 1 shows the bound styrene content of the modified SBR C obtained, the bound vinyl content of the butadiene moiety, and Mn and Mw.

Production Example 5 Production of Modified SBR D In the modification reaction step in Production Example 2, 0.43 mmol of modifier X was added, and after 15 minutes of modification reaction at 50 ° C., bis (2-ethylhexanoate) tin 0 Modified SBR D was obtained in the same manner as in Production Example 2 except that .43 mmol was added and the reaction was further performed at 50 ° C. for 15 minutes. Table 1 shows the bound styrene content of the modified SBR D obtained, the bound vinyl content of the butadiene moiety, and Mn and Mw.

Production Example 6 Production of Modified SBR E In the modification reaction step in Production Example 2, 0.43 mmol of modifier X was added, and after 15 minutes of modification reaction at 50 ° C., bis (2-ethylhexanoate) zirconium oxide Modified SBR E was obtained in the same manner as in Production Example 2 except that 0.43 mmol was added and the reaction was further performed at 50 ° C. for 15 minutes. Table 1 shows the bound styrene content of the modified SBR E obtained, the bound vinyl content of the butadiene moiety, and Mn and Mw.

Production Example 7 Production of Modified SBR F In the modification reaction step in Production Example 2, the modification agent 3-N, N-aminopropyltriethoxysilane was used in place of the modifier X in the same manner as in Production Example 2. Modified SBR F was obtained. Table 1 shows the bound styrene content of the modified SBR F obtained, the bound vinyl content of the butadiene moiety, and Mn and Mw.

Production Example 8 Production of Modified SBR G Manufacture except that the modifier 3-N, N-bis (trimethylsilyl) aminopropyl (dimethyl) ethoxysilane was used instead of the modifier X in the modification reaction step in Production Example 2. Modified SBR G was obtained in the same manner as in Example 2. Table 1 shows the bound styrene content of the modified SBR G obtained, the bound vinyl content of the butadiene moiety, and Mn and Mw.

Production Example 9 Production of Modified SBR H Modified SBR H was obtained in the same manner as in Production Example 2 except that, in the modification reaction step in Production Example 2, a modifying agent tin tetrachloride was used instead of the modifying agent X. Table 1 shows the bound styrene content of the modified SBR H obtained, the bound vinyl content of the butadiene moiety, and Mn and Mw.

Production Example 10 Production of Modified SBR I In the modification reaction step in Production Example 2, instead of modifier X, modifier N- (1,3-dimethylbutylidene) -3- (triethoxysilyl) -1-propylamine A modified SBR I was obtained in the same manner as in Production Example 2 except that was used. Table 1 shows the bound styrene content of the modified SBR I obtained, the bound vinyl content of the butadiene moiety, and Mn and Mw.

Production Example 11 Production of Modified SBR J Modified SBR J was obtained in the same manner as in Production Example 2 except that the modifier tetraethoxysilane was used in place of the modifier X in the modification reaction step in Production Example 2. Table 1 shows the bound styrene content of the modified SBR J obtained, the bound vinyl content of the butadiene moiety, and Mn and Mw.

［注］
１）変性剤Ｘ：３−Ｎ，Ｎ−ビス（トリメチルシリル）アミノプロピル（メチル）ジエトキシシラン
２）変性剤（ａ）：３−Ｎ，Ｎ−ビス（トリメチルシリル）アミノプロピルトリエトキシシラン
３）変性剤（ｂ）：３−Ｎ，Ｎ−ビス（トリメチルシリル）アミノプロピル（ジメチル）エトキシシラン
４）縮合促進剤Ｓ−１：テトラキス（２−エチルヘキシルオキシ）チタン
５）縮合促進剤Ｓ−２：テトラキス（２−エチル−１，３−ヘキサンジオラト）チタン
６）縮合促進剤Ｓ−３：ビス（２−エチルヘキサノエート）スズ
７）縮合促進剤Ｓ−４：ビス（２−エチルヘキサノエート）酸化ジルコニウム
８）変性剤（ｃ）：四塩化スズ
９）変性剤（ｄ）：Ｎ−（１，３−ジメチルブチリデン）−３−（トリエトキシシリル）−1−プロピルアミン
１０）変性剤（ｅ）：テトラエトキシシラン

[note]
1) Modification agent X: 3-N, N-bis (trimethylsilyl) aminopropyl (methyl) diethoxysilane 2) Modification agent (a): 3-N, N-bis (trimethylsilyl) aminopropyltriethoxysilane 3) modification Agent (b): 3-N, N-bis (trimethylsilyl) aminopropyl (dimethyl) ethoxysilane 4) condensation accelerator S-1: tetrakis (2-ethylhexyloxy) titanium 5) condensation accelerator S-2: tetrakis ( 2-ethyl-1,3-hexanediolato) titanium 6) condensation accelerator S-3: bis (2-ethylhexanoate) tin 7) condensation accelerator S-4: bis (2-ethylhexanoate) Zirconium oxide 8) modifier (c): tin tetrachloride 9) modifier (d): N- (1,3-dimethylbutylidene) -3- (triethoxysilyl) -1-propylamino 10) Modifier (e): Tetraethoxysilane

Production Example 12 Production of Unmodified Low Molecular Weight SBR (hereinafter, “Low Molecular Weight SBR” is abbreviated as LM-SBR) S In an 800 mL pressure-resistant glass container dried and purged with nitrogen, 300 g of cyclohexane, 1,3-butadiene After adding 40 g, 13 g of styrene, 0.90 mmol of ditetrahydrofurylpropane, and further adding 0.90 mmol of n-butyllithium, a polymerization reaction was performed at 50 ° C. for 2 hours. The polymerization conversion rate at this time was almost 100%. Thereafter, 0.5 mL of an isopropanol solution of 2,6-di-t-butyl-p-cresol (concentration: 5% by mass) is added to the polymerization reaction system to stop the polymerization reaction, and further dried according to a conventional method. Unmodified LM-SBR S was obtained. Table 2 shows the bound styrene content of the unmodified LM-SBR, the bound vinyl content of the butadiene moiety, and Mw.

Production Example 13 Production of Unmodified LM-BR A ′ Unmodified BR A ′ was obtained in the same manner as in Production Example 12 except that the styrene monomer was not added. Table 2 shows the bound vinyl content of the butadiene portion before modification of the obtained modified LM-BR A ′, and Mw.

Production Example 14 Production of Unmodified LM-SBR B ′ <Production of LM-SBR with Active End>
After adding 300 g of cyclohexane, 8 g of 1,3-butadiene, 45 g of styrene, 0.90 mmol of ditetrahydrofurylpropane, and further adding 0.90 mmol of n-butyllithium to an 800 mL pressure-resistant glass container that has been dried and purged with nitrogen. The polymerization reaction was carried out at 50 ° C. for 2 hours. The polymerization conversion rate at this time was almost 100%. Thereafter, 0.5 mL of an isopropanol solution of 2,6-di-t-butyl-p-cresol (concentration: 5% by mass) is added to the polymerization reaction system to stop the polymerization reaction, and further dried according to a conventional method. Unmodified LM-SBR was obtained. Table 2 shows the bound styrene content of the unmodified LM-SBR, the bound vinyl content of the butadiene moiety, and Mw.

Production Example 15 Production of Modified LM-SBR C ′ To an 800 mL pressure-resistant glass container dried and purged with nitrogen, 300 g of cyclohexane, 40 g of 1,3-butadiene, 13 g of styrene, 0.90 mmol of ditetrahydrofurylpropane were added. After adding 0.90 mmol of n-butyllithium, a polymerization reaction was performed at 50 ° C. for 2 hours. The polymerization conversion rate at this time was almost 100%.
<Modification reaction process>
Next, 0.225 mmol of a modifier tetraethoxysilane was added to the polymerization reaction system, and a modification reaction was further performed at 50 ° C. for 30 minutes.
<Post-polymerization treatment>
Next, 0.5 mL of an isopropanol solution of 2,6-di-t-butyl-p-cresol (concentration: 5 mass%) is added to the polymerization reaction system to stop the polymerization reaction, and further dried according to a conventional method. Modified LM-SBR C ′. Table 2 shows the bound styrene content before modification of the obtained modified LM-SBR C ', the bound vinyl content of the butadiene moiety, and Mw.

Production Examples 16 to 20 Production of Modified LM-SBR D ′ to G ′ Production Examples except that 0.81 mmol of each of the modifiers shown in Table 2 was used instead of tetraethoxysilane in the modification reaction step in Production Example 15. In the same manner as in Example 15, modified LM-SBR D ′ to H ′ were obtained. Table 2 shows the bound styrene content of each modified LM-SBR obtained before modification, the bound vinyl content of the butadiene portion, and Mw.

Production Example 20 Production of Modified LM-SBR H ′ In the modification reaction step in Production Example 15, N- (1,3-dimethylbutylidene) -3- (triethoxysilyl) -1-propanamine was added as a modifying agent in an amount of 0. 81 mmol was added and the denaturation reaction was carried out at 50 ° C. for 15 minutes, 0.43 mmol of bis (2-ethylhexanoate) tin was added, and the reaction was further carried out at 50 ° C. for 15 minutes. To obtain modified LM-SBR I ′. Table 2 shows the bound styrene content before modification of the obtained modified LM-SBR I ', the bound vinyl content of the butadiene moiety, and Mw.

Production Example 21 Production of low molecular weight SBRs T and U having different molecular weights In Production Example 2, SBR having a weight average molecular weight of 3000 (T) and 220,000 (U) was obtained by changing the amount of butyl lithium as a polymerization catalyst. .

［注］
１）変性剤Ｘ及び６）縮合促進剤Ｓ−３は、第１表の脚注と同じである。
８）変性剤（ｃ）：四塩化スズ
９）変性剤（ｄ）：Ｎ−（１，３−ジメチルブチリデン）−３−（トリエトキシシリル）−１−プロパンアミン
１１）変性剤（ｆ）：Ｎ，Ｎ’−ジエチルアミノベンゾフェノン
１２）変性剤（ｇ）：ジメチルイミダゾリジノン
１３）変性剤（ｈ）：Ｎ−メチルピロリドン
１４）変性剤（ｉ）：Ｎ−（３−トリエトキシシリルプロピル）−４，５−ジヒドロイミダゾール

[note]
1) modifier X and 6) condensation accelerator S-3 are the same as the footnotes in Table 1.
8) Modifier (c): Tin tetrachloride 9) Modifier (d): N- (1,3-dimethylbutylidene) -3- (triethoxysilyl) -1-propanamine 11) Modifier (f) : N, N'-diethylaminobenzophenone 12) modifier (g): dimethylimidazolidinone 13) modifier (h): N-methylpyrrolidone 14) modifier (i): N- (3-triethoxysilylpropyl) -4,5-dihydroimidazole

Examples 1-5 and Comparative Examples 1-6
Each rubber composition was prepared in accordance with Formulations I and II shown in Table 3 in combination with the unmodified SBR, modified SBR and unmodified low molecular weight SBR S obtained in Production Examples 1-11.

［注］
１）製造例１〜１１で製造した無変性ＳＢＲ、変性ＳＢＲ Ａ〜Ｊ
２）ＩＳＡＦ、窒素吸着比表面積（Ｎ₂ＳＡ）＝１１１ｍ²／ｇ
３）東ソーシリカ社製「ニプシルＡＱ」
４）アロマオイル又は無変性の低分子量ＳＢＲ Ｓ
５）Ｎ−（１，３−ジメチルブチル）−Ｎ’−フェニル−ｐ−フェニレンジアミン
６）デグサ社製「Ｓｉ６９」、ビス（３−トリエトキシシリルプロピル）テトラスルフィド
７）メルカプトベンゾチアジルジスルフィド
８）ジフェニルグアニジン
９）Ｎ−ｔ−ブチル−２−ベンゾチアゾリルスルフェンアミド

[note]
1) Unmodified SBR and modified SBR A to J produced in Production Examples 1 to 11
2) ISAF, nitrogen adsorption specific surface area (N ₂ SA) = 111 m ² / g
3) “Nipsil AQ” manufactured by Tosoh Silica Corporation
4) Aroma oil or unmodified low molecular weight SBR S
5) N- (1,3-dimethylbutyl) -N′-phenyl-p-phenylenediamine 6) “Si69” manufactured by Degussa, bis (3-triethoxysilylpropyl) tetrasulfide 7) mercaptobenzothiazyl disulfide 8 ) Diphenylguanidine 9) Nt-butyl-2-benzothiazolylsulfenamide

Each rubber composition was vulcanized at 160 ° C. for 15 minutes to obtain a vulcanized rubber, the abrasion resistance and loss tangent (tan δ) of the vulcanized rubber were determined, and the index was displayed with the control as 100.
As a control, a rubber composition using the unmodified SBR obtained in Production Example 1 and using an aroma oil instead of LM-SBR was used.
The higher the index value, the better the wear resistance, and the lower the index value, the lower the heat generation of tan δ.
The results are shown in Table 4.

Examples 6-18 and Comparative Examples 7-10
Each rubber composition was prepared according to Formulations I and II shown in Table 3 in combination with the modified SBR which is the matrix B obtained in Production Example 3 and the modified low molecular weight SBR obtained in Production Examples 12 to 20.
Each rubber composition was vulcanized at 160 ° C. for 15 minutes to obtain a vulcanized rubber, the abrasion resistance and loss tangent (tan δ) of the vulcanized rubber were determined, and the index was displayed with the control as 100.
As a control, a rubber composition using the unmodified SBR obtained in Production Example 1 and using an aroma oil instead of LM-SBR was used.
The higher the index value, the better the wear resistance, and the lower the index value, the lower the heat generation of tan δ.
The results are shown in Table 5.

［注］
１０）変性剤（ｅ）は、第１表の脚注と同じである。
１５）変性剤（ｊ）：ヘキサメチレンイミン

[note]
10) The modifier (e) is the same as the footnote in Table 1.
15) Denaturant (j): Hexamethyleneimine

表５より次のことが分かる。
本発明の実施例はカーボンブラック配合、シリカ配合いずれも耐摩耗性、低発熱性に優れている。
一方、特に比較例９は優れた耐摩耗性、低発熱性は得られているが、低分子量ＳＢＲの重量平均分子量が高いことにより工業作業性が非常に劣る。

Table 5 shows the following.
In the examples of the present invention, both the carbon black compounding and the silica compounding are excellent in wear resistance and low heat generation.
On the other hand, in particular, Comparative Example 9 has excellent wear resistance and low heat build-up, but industrial workability is very poor due to the high weight average molecular weight of the low molecular weight SBR.

  The rubber composition of the present invention can provide a tire with greatly improved low heat buildup and wear resistance.

Claims (38)

  (A) A rubber component containing 10% by mass or more of a modified conjugated diene polymer having at least one reactive functional group having a polystyrene equivalent weight average molecular weight of 200,000 or more measured by gel permeation chromatography, and 100 parts by mass thereof On the other hand, (B) 20 parts by mass or more of reinforcing filler, and (C) unmodified or unmodified and / or unmodified and / or modified low weight average molecular weight less than 5,000 to 200,000 The functional group of the modified conjugated diene polymer in the component (A) was protected with a protic amino group or a group removable by hydrolysis, containing 5 to 60 parts by mass of a molecular weight conjugated diene polymer. A rubber composition comprising an amino group and a silicon atom-containing group.   The amino group protected with a protic amino group or a detachable group is a primary amino group, or a primary amino group or a secondary amino group protected with a secondary amino group or a detachable group. Item 2. The rubber composition according to Item 1.   The rubber composition according to claim 1 or 2, wherein the functional group containing a silicon atom is a hydrocarbyloxy group, a hydroxy group or a halogen atom directly bonded to the silicon atom.   The rubber composition according to any one of claims 1 to 3, wherein the modified conjugated diene polymer in the component (A) has a functional group at a terminal.   The modified conjugated diene polymer in component (A) has an amino group protected with a protic amino group or a detachable group at the same end, and a functional group containing a silicon atom. A rubber composition according to any one of the above.   6. The rubber composition according to claim 5, wherein the same terminal is a polymerization termination terminal. The modified conjugated diene polymer in component (A) has the following general formula (1) as a modifier at the active end of the conjugated diene polymer having an active end.

[Wherein, A ¹ is a halogen atom or a hydrocarbyloxy group having 1 to 20 carbon atoms, R ² is a hydrocarbon group R ³ is a hydrocarbon group, L ¹ is a detachable functional group, and L ² is detachable. a possible group or a hydrocarbon group, when L ² is eliminable functional group, may be a different structure in L ¹ and the same structure, and L ¹ and L ² may be bonded. n represents 0 or 1, and m represents 1 or 2. ]
General formula (2)

(Wherein R ⁴ is a hydrocarbon group having 1 to 20 carbon atoms, R ⁵ is a hydrocarbon group having 1 to 12 carbon atoms, and A ² and A ³ are each independently a halogen atom or hydrocarbyloxy having 1 to 20 carbon atoms. Group L ³ is a detachable functional group or hydrocarbon group, L ⁴ is a detachable functional group, k is 0 or 1, and f is an integer of 1 to 10.)
And general formula (3)

(In the formula, A ⁴ is a halogen atom or a hydrocarbyloxy group having 1 to 20 carbon atoms, R ⁶ is a hydrocarbon group having 1 to 20 carbon atoms, R ⁷ is a hydrocarbon group having 1 to 12 carbon atoms, and L ⁵ is a desorbing group. A separable functional group or hydrocarbon group, q represents ˜0 or 1.)
The rubber composition according to any one of claims 1 to 6, which is selected from silane compounds represented by the formula:   The rubber composition according to any one of claims 1 to 7, wherein the detachable group is a trialkylsilyl group having 1 to 4 carbon atoms.   The modifier is N, N-bis (trimethylsilyl) aminopropylmethyldimethoxysilane, N, N-bis (trimethylsilyl) aminopropylmethyldiethoxysilane, N, N-bis (trimethylsilyl) aminopropylmethylmethoxychlorosilane or N, N The rubber composition according to claim 7, which is bis (trimethylsilyl) aminopropylmethylethoxychlorosilane.   The modifier is 1-trimethylsilyl-2-ethoxy-2-methyl-1-aza-2-sila-cyclopentane, 1-trimethylsilyl-2-methoxy-2-methyl-1-aza-2-silacyclopentane, 1 The rubber composition according to claim 7 or 8, which is -trimethylsilyl-2,2-diethoxy-1-aza-2-silacyclopentane or 1-trimethylsilyl-2,2-dimethoxy-1-aza-2-silacyclopentane. object.   The conjugated diene polymer in component (A) was obtained by reacting the active end of the conjugated diene polymer having an active end with a modifier and then subjecting it to heat treatment in the presence of a condensation accelerator. The rubber composition according to any one of claims 7 to 10, which is a product.   The modified conjugated diene polymer in component (A) hydrolyzes the functional group formed by bonding to the active end of the conjugated diene polymer, and converts the protected amino group in the group into a free amino group. The rubber composition according to any one of claims 7 to 11, which is formed by:   The modified conjugated diene polymer in component (A) is polymerized using an alkali metal compound as a polymerization initiator or a catalyst system comprising a rare earth metal compound. The rubber composition as described in 2.   The rubber composition according to claim 13, wherein the alkali metal compound is alkyl lithium or lithium amide.   The modified conjugated diene polymer in component (A) is a 1,3-butadiene and / or isoprene polymer, or a copolymer of 1,3-butadiene and / or isoprene and an aromatic vinyl compound. The rubber composition in any one of -14.   The rubber composition according to claim 15, wherein the aromatic vinyl compound is styrene.   The rubber composition according to any one of claims 1 to 16, wherein the reinforcing filler (B) is carbon black and / or silica.   The rubber composition according to claim 17, wherein the total content of carbon black and silica is 20 to 120 parts by mass with respect to 100 parts by mass of the (A) rubber component.   The rubber composition according to claim 17 or 18, wherein the content of silica is 50 parts by mass or more with respect to 100 parts by mass of the rubber component (A).   The rubber composition according to any one of claims 1 to 19, wherein the unmodified and / or modified low molecular weight conjugated diene polymer of component (C) is a low molecular weight aromatic vinyl compound-conjugated diene compound copolymer.   The rubber composition according to any one of claims 1 to 20, wherein the aromatic vinyl compound unit in the unmodified and / or modified low molecular weight conjugated diene polymer of the component (C) is a styrene unit.   The rubber composition according to any one of claims 1 to 21, wherein the conjugated diene compound unit in the unmodified and / or modified low molecular weight conjugated diene polymer is 1,3-butadiene and / or isoprene unit.   23. The rubber composition according to claim 21, wherein the unmodified and / or modified low molecular weight aromatic vinyl compound-conjugated diene compound copolymer is a solution-polymerized styrene-butadiene copolymer rubber.   The unmodified and / or modified low molecular weight conjugated diene polymer of the component (C) contains 10% by mass of a modified low molecular weight conjugated diene polymer having at least one functional group. Rubber composition.   The rubber composition according to claim 24, wherein the functional group is a functional group containing nitrogen, silicon, or tin.   The functional group containing nitrogen is a primary amino group, a primary amino group protected with a detachable group, a substituted amino group, an amide group, an imino group, an imidazole residue, a nitrile group or a pyridyl group. The rubber composition as described in 2.   27. The rubber composition according to claim 26, wherein the detachable protecting group is a C1-C4 trialkylsilyl group.   The modifier is N, N-bis (trimethylsilyl) aminopropylmethyldimethoxysilane, N, N-bis (trimethylsilyl) aminopropylmethyldiethoxysilane, N, N-bis (trimethylsilyl) aminopropylmethylmethoxychlorosilane or N, N The rubber composition according to any one of claims 25 to 27, which is -bis (trimethylsilyl) aminopropylmethylethoxychlorosilane.   The modifier is 1-trimethylsilyl-2-ethoxy-2-methyl-1-aza-2-sila-cyclopentane, 1-trimethylsilyl-2-methoxy-2-methyl-1-aza-2-silacyclopentane, 1 28. A trimethylsilyl-2,2-diethoxy-1-aza-2-silacyclopentane or 1-trimethylsilyl-2,2-dimethoxy-1-aza-2-silacyclopentane. Rubber composition. The functional group containing nitrogen is represented by the following general formula (4)

[Wherein, R ⁸ and R ⁹ each independently represents an alkyl group having 1 to 12 carbon atoms, a cycloalkyl group having 3 to 12 carbon atoms, or an aralkyl group having 7 to 12 carbon atoms. ]
A substituted amino group represented by general formula (5):

[Wherein, R ¹⁰ represents an alkylene group having 3 to 16 methylene groups, a substituted alkylene group, an oxyalkylene group or an N-alkylaminoalkylene group. ]
The rubber composition according to claim 25, which is a group selected from cyclic amino groups represented by: The modified product of the low molecular weight conjugated diene polymer has the following general formula (6) at the active end of the low molecular weight conjugated diene polymer having an active end.

[In the formula, A ⁵ represents (thio) epoxy group, (thio) isocyanate group, (thio) carbonyl group, (thio) formyl group, imine residue, amide group, isocyanuric acid triester residue, (thio) carboxyl One having at least one functional group selected from an acid hydrocarbyl ester residue, a metal salt residue of (thio) carboxylic acid, a carboxylic acid anhydride residue, a carboxylic acid halide residue, and a carbonic acid dihydrocarbyl ester residue A valent group, R ¹¹ and R ¹² are each independently a monovalent aliphatic hydrocarbon group having 1 to 20 carbon atoms or a monovalent aromatic hydrocarbon group having 6 to 18 carbon atoms, and R ¹³ is a single bond or carbon. indicates the number of 1 to 20 divalent inert hydrocarbon group, n is an integer of 1 to 3, if the OR ¹¹ there are multiple to a plurality of OR ¹¹ may be the same or different, R ¹² is If there are multiple, multiple R ¹² It may be the same or different, do not include active proton and onium salt in the molecule. ]
And a partial condensate thereof, and the general formula (7)
R ¹⁴ _p -Si- (OR ¹⁵ ) _4-p (7)
[Wherein, R ¹⁴ and R ¹⁵ each independently represent a monovalent aliphatic hydrocarbon group having 1 to 20 carbon atoms or a monovalent aromatic hydrocarbon group having 6 to 18 carbon atoms; an integer 2, if the OR ¹⁵ there are multiple to a plurality of OR ¹⁵ may be the same or different, if R ¹⁴ is plural, R ¹⁴ may be the same or different in the molecule Does not include active protons and onium salts. ]
The rubber composition according to any one of claims 25 to 30, wherein the rubber composition is obtained by reacting at least one selected from a hydrocarbyloxysilane compound represented by formula (1) and a partial condensate thereof. A modified product of a low molecular weight conjugated diene polymer is represented by the following general formula (8):
R ¹⁶ _a ZX _b (8)
[Wherein R ¹⁶ is an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 3 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, or an aralkyl group having 7 to 20 carbon atoms, and Z is a tin atom or silicon. An atom, X represents a chlorine atom or a bromine atom, a is 0 to 3, b is 1 to 4, and when there are a plurality of R ^{16 s} , a plurality of R ^{11 s} may be the same or different; In some cases, multiple Xs may be the same or different and a + b = 4. ]
The rubber composition according to any one of claims 25 to 31, which has at least one tin-carbon bond or silicon-carbon bond derived from a coupling agent represented by the formula:   The rubber composition according to any one of claims 25 to 32, wherein the functional group of the modified product of the low molecular weight conjugated diene polymer has an interaction with the reinforcing filler of the component (B).   The unmodified and / or modified low molecular weight conjugated diene polymer of the component (C) is an unmodified product or a property before modification and has a weight average molecular weight of 20,000 to 200,000. The rubber composition in any one.   The unmodified and / or modified low molecular weight conjugated diene polymer of the component (C) is an unmodified product or a property before modification, and has a weight average molecular weight of 30,000 to 150,000. Rubber composition.   The modified conjugated diene polymer in the component (A) has an amino group protected with a protic amino group or a detachable group as a functional group, and a silicon atom-containing group, and the component (C) The modified low-molecular-weight conjugated diene polymer in (1) has an amino group protected with a protic amino group or a detachable group as a functional group, and a silicon atom-containing group. Rubber composition.   The rubber composition according to any one of claims 1 to 36, which comprises natural rubber and / or synthetic isoprene rubber in addition to (A) as a rubber component.   A tire using the rubber composition according to any one of claims 1 to 37 for any of a tread, a base, a side, and an inner liner.