JP2001192504A - Method for producing conjugated diene rubber composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fracturing property, abrasion resistance and low heat build-up (low rolling resistance) by mixing a conjugated diene polymer having a specific microstructure dissolved in an organic solvent with a filler. A rubber composition that excels in fuel economy) and satisfies various requirements such as wet grip performance and processability in a well-balanced manner. SOLUTION: 1,4-cis bond content is 85% or more;
The 1,2-vinyl bond content is 2.0% or less, and the ratio of the weight average molecular weight (Mw) to the number average molecular weight (Mn) (Mw / M
n) is 3.5 or less, and the Mooney viscosity (ML _{1 + 4} , 100
C.) is 10 to 70, and a conjugated diene polymer having a ratio (SV / MV) of 2 to 15 between the solution viscosity (SV) and the Mooney viscosity (MV) is 2 to 15 and mixed with a filler in a state of being dissolved in an organic solvent. Then, a rubber composition is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a fracture characteristic, abrasion resistance and low heat build-up (low rolling resistance) obtained by mixing a specific conjugated diene-based polymer with a filler in a state of being dissolved in an organic solvent. , Low fuel consumption).

[0002]

2. Description of the Related Art Numerous proposals have been made for polymerization catalysts for conjugated dienes, and they play an extremely important role industrially. In particular, for the purpose of obtaining a conjugated diene-based polymer having improved performance in thermal and mechanical properties, many polymerization catalysts giving a high cis 1,4 bond content have been studied and developed. For example, composite catalyst systems containing transition metal compounds such as nickel, cobalt, and titanium as main components are known, and some of them are already industrially widely used as polymerization catalysts for butadiene, isoprene, and the like [ End. Ing. Chem. , 48,78
4 (1956), JP-B-37-8198].

[0003] In recent years, attempts have been made to improve the tensile stress and fracture characteristics of rubber compositions using the above-mentioned polymers and compounding fillers. For example, in tire applications, there is a demand for a rubber composition that has a good balance of various properties such as processability and fracture properties, and is excellent in abrasion resistance and low heat build-up as the performance of tires is improved. In order to improve abrasion resistance and low heat build-up, development of a polymer having a high 1,4-cis bond content and a small degree of polymer chain branching has been studied. In Japanese Patent Publication No. 61-54808, a cobalt compound, diethylaluminum chloride and water are used.
JP-A-10-7717, JP-A-11-14011
No. 8 reports that a combination of a cobalt compound and an alumoxane can polymerize a polymer having a high 1,4-cis bond content and a narrow molecular weight distribution.

On the other hand, in order to achieve a higher 1,4-cis bond content, a composite catalyst system comprising a rare earth metal compound and a group I-III organometallic compound has also been studied and developed. For example, Japanese Patent Publication No. 47-14729 discloses a catalyst system comprising a rare earth metal compound such as cerium octanoate and an alkyl aluminum hydride such as diisobutyl aluminum hydride or an aluminum halide such as a trialkyl aluminum and ethyl aluminum dichloride. In particular, it has been shown that aging the catalyst in the presence of butadiene increases the catalytic activity. Also, JP-A-6-219916, JP-A-6-306113, JP-A-8-73515, JP-A-10-306113, and JP-A-11-3
No. 5633 reports that when a catalyst system using methylalumoxane as a neodymium compound is used, a conjugated diene polymer having high polymerization activity and a narrow molecular weight distribution can be obtained. However, even when a rubber composition containing a filler is produced using these conjugated diene-based polymers, the reinforcing effect between the polymer and the filler is insufficient, so that the effect of improving abrasion resistance and low heat generation is reduced. Is not sufficient, and further improvement in properties is desired.

[0005]

As a result of intensive studies, the present inventors have found that certain microstructures, ie, high 1,4
A conjugated diene polymer having a narrow cis bond content and a low 1,2-vinyl bond content and a narrow molecular weight distribution, such as a conjugated diene polymer polymerized using a rare earth element or transition metal catalyst, is dissolved in an organic solvent. By using a rubber composition obtained by mixing with a filler in a state where it has been used, it has excellent breaking characteristics, abrasion resistance and low heat generation (low rolling resistance, low fuel consumption) and various properties such as wet grip performance and workability. The inventors have found that the required characteristics are satisfied in a well-balanced manner, and have reached the present invention.

[0006]

According to the present invention, a 1,4-cis bond content is 85% or more, and a 1,2-vinyl bond content is 2.8%.
0% or less, weight average molecular weight (Mw) and number average molecular weight (M
n), the Mooney viscosity (ML _{1 + 4} , 100 ° C.) is 10 to 70,
Mixing the conjugated diene polymer having a ratio (SV / MV) of the solution viscosity (SV) measured at 5 ° C. to the above Mooney viscosity (MV) of 2 to 15 with the filler dissolved in an organic solvent. And a method for producing a rubber composition characterized by the following. Here, the conjugated diene-based polymer is preferably a polymer having its terminal modified. The filler is preferably carbon black and / or silica.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION The method for producing a rubber composition of the present invention is characterized in that, first, a conjugated diene polymer having a specific microstructure and Mooney viscosity is used. Here, the conjugated diene polymer used in the present invention has a 1,4-cis bond content of 85% or more, preferably 9% or more.
0% or more, the 1,2-vinyl bond content is 2.0% or less, preferably 1.5% or less, and the ratio (Mw / Mn) of the weight average molecular weight (Mw) to the number average molecular weight (Mn) is 3. 5 or less,
Preferably it is 3.0 or less. Outside these ranges, the mechanical properties and the wear resistance are inferior. Mooney viscosity of the conjugated diene polymer (ML _{1 + 4} , 100 ° C.)
Is 10 to 70, preferably 15 to 60, and more preferably 20 to 50. If it is less than 10, the breaking strength is inferior, while if it exceeds 70, the workability is inferior, which is not preferable. Furthermore, the ratio (SV / MV) between the solution viscosity (SV) (measured in toluene at 25 ° C.) and the Mooney viscosity (MV) of the conjugated diene polymer used in the present invention indicates the degree of branching of the polymer chain. Here, SV represents the solution viscosity of the conjugated diene-based polymer in toluene. When SV / MV is large, it indicates that the degree of branching of the polymer is small.
When V is large, the degree of branching increases. The conjugated diene polymer used in the present invention has an SV / MV of 2 to 15, preferably 2.5 to 10. If SV / MV is less than 2,
Abrasion resistance and low heat build-up are inferior, and the die well is undesirably large. On the other hand, when SV / MV exceeds 15, the solution viscosity becomes too high, and the synthesis becomes difficult.

The conjugated diene-based polymer can be obtained by polymerizing a conjugated diene-based compound in the presence of a rare earth element-based catalyst or a transition element-based catalyst. Further, the conjugated diene-based polymer may be a modified conjugated diene-based polymer obtained by polymerizing a conjugated diene-based polymer with a rare-earth element-based catalyst and subsequently reacting with a terminal modifier. The above-mentioned modified conjugated diene-based polymer and unmodified conjugated diene-based polymer can be used alone or in combination of one kind. It is preferable in terms of stability.

The conjugated diene compound which can be polymerized with the rare earth catalyst or the transition metal catalyst is as follows.
Examples include 1,3-butadiene, 2-methyl-1,3-butadiene (isoprene), 2,3-dimethyl-1,3-butadiene, 1,3-pentadiene, 1,3-hexadiene, and myrcene. Preferred are 1,3-butadiene, isoprene and 1,3-pentadiene. Further, these conjugated diene-based polymers may be used alone or as a mixture of two or more kinds. In this case, a copolymer is obtained.

As the rare earth element-based catalyst used for the polymerization of the conjugated diene-based polymer, known catalysts can be used. For example, a catalyst comprising a combination of (a) a lanthanum series rare earth element compound, (b) an organoaluminum compound, (c) an alumoxane, (d) a halogen-containing compound, and if necessary, a Lewis base can be used. here,
(A) As the lanthanum series rare earth element compound, a metal halide, a carboxylate, an alcoholate, a thioalcoholate, an amide or the like having an atomic number of 57 to 71 is used. Specific examples of the (a) lanthanide series rare earth element compound are described in detail in, for example, paragraphs “0015” to “0020” of Japanese Patent Application No. 11-117511. Further, (b) the organoaluminum compound includes AlR ¹ R ² R ³ (where R ¹ , R ² and R ³
Are the same or different and each represent a hydrogen atom or a hydrocarbon residue having 1 to 8 carbon atoms). Specific examples of (b) the organoaluminum compound include trimethylaluminum, triethylaluminum, tri-n-propylaluminum, triisobutylaluminum, tri-t-butylaluminum, and the like. For example, Japanese Patent Application No. 11-117511. It is described in detail in paragraph number “0024” of the specification. further,
(C) The alumoxane is represented by the following formula (I) or the following formula (I
This is a compound having a structure represented by I). Also, Fine Chemicals, 23, (9), 5 (1994); A
m. Chem. Soc. , 115, 4971 (199
3). Am. Chem. Soc. , 117,646
5 (1995).

[0011]

[0012]

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(Wherein, in the formula, when there are a plurality of R ⁴ , R ⁴ is the same or different and is a hydrocarbon group containing 1 to 20 carbon atoms, and n is an integer of 2 or more.) (C) For specific examples of alumoxanes, for example, see paragraph number “0” of Japanese Patent Application No. 11-117511.
021 "to" 0024 ". further,
(D) As the halogen-containing compound, AlX _n R
_3-n (where X is halogen and R is
-20 hydrocarbon residues, for example, an alkyl group, an aryl group, or an aralkyl group, and n is 1, 1.5, 2, or 3);
Organic halides such as butyl chloride and benzyl chloride, Me ₃ Si Cl, Me ₂ Si Cl ₂ , MeSi HC
l ₂ , halogenated organosilicon compounds such as MeSiCl ₃ ; metal halides such as silicon tetrachloride, tin tetrachloride, titanium tetrachloride, magnesium chloride, manganese chloride, zinc chloride and phosphoric acid triester, carboxylic acid or alcohol Is used. (D) Specific examples of the halogen-containing compound include, for example, Japanese Patent Application No. 11-117511.
And the composition ratio of these components (a) to (d), the catalyst production conditions, and the like are described in the paragraph number “002” of the same specification.
8 "to" 0030 ".

The Lewis base optionally used is used for complexing (a) a lanthanum series rare earth element compound or (d) a halogen-containing compound. Examples thereof include acetylacetone, kent alcohol, carboxylic acid, and phosphorus. Acid esters and the like are preferably used. Above all, the use of a neodymium catalyst using a neodymium compound as a lanthanum series rare earth element compound has led to excellent polymerization of a conjugated diene polymer having a high content of 1,4-cis bonds and a low content of 1,2-vinyl bonds. It is preferable because it can be obtained by activity. A specific example of the above rare earth element-based catalyst is disclosed in Japanese Patent Application No. 11-1175 described above.
No. 11, JP-B-62-1404, JP-B-1-16244, and paragraph numbers "0014" to "0" of JP-A-11-35633 by the present applicant.
028 ”and paragraph Nos.“ 0016 ”to“ 0031 ”of Japanese Patent Application No. 10-59098, and these can be used.

When (a) a conjugated diene compound is polymerized in the presence of a rare earth element-based catalyst using a lanthanum series rare earth element compound (La compound), the cis content and Mw / Mn must be within the above ranges. The conjugated diene-based compound / (a) La compound is usually in a molar ratio of 1,000 to
2 million, particularly preferably 5,000 to 1,000,000, and (b) an organoaluminum compound (AlR ¹
R ² R ³ ) / (a) La compound is in a molar ratio of 1 to 1,0.
00, particularly preferably 3 to 500. Further, (d) a halogen-containing compound / (a) a La compound is
The molar ratio is preferably from 0.1 to 30, particularly preferably from 0.2 to 15. The molar ratio of the Lewis base / (a) La compound is preferably 0 to 30, particularly preferably 1 to 10. Further, the ratio of the component (a) to the component (c) is a molar ratio,
The ratio of component (a) to component (c) is from 1: 1 to 1: 500, preferably from 1: 3 to 1: 250. In the polymerization, a solvent may be used, or bulk polymerization or gas phase polymerization may be performed without using a solvent. The polymerization temperature is usually -30C to 15C.
0 ° C, preferably 10 to 100 ° C. Examples of the solvent include a conjugated diene-based polymer solvent used when mixed with the filler, as described later.

The modified conjugated diene polymer can be obtained by reacting a terminal modifier with the active terminal of the polymer following the above polymerization. Examples of the terminal modifier include the compounds described in the following (e) to (j). ^{_{(E) R 4 n M'X 4}} -n, M'X 4, M'X 3, R 4 n
^{M '(-R 5 -COOR 6)} 4-n or R ⁴ _n M' (-
R ⁵ —COR ⁶ ) _4-n (wherein, R ⁴ and R ⁵ are the same or different, and are a hydrocarbon group containing 1 to 20 carbon atoms, and R ⁶ is a 1 to 20 carbon atom. A hydrocarbon group containing a carbonyl group or an ester group in the side chain, M 'is a tin atom, a silicon atom, a germanium atom or a phosphorus atom, X is a halogen atom, and n is 0 to 0.
A halogenated organometallic compound, a metal halide compound or an organometallic compound corresponding to (3). (F) A heterocumulene containing a Y ＝ C ＝ Z bond (wherein Y is a carbon atom, an oxygen atom, a nitrogen atom or a sulfur atom, and Z is an oxygen atom, a nitrogen atom or a sulfur atom) in the molecule. Compound. (G) In the molecule

[0017]

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Heterocyclic three-membered ring compounds containing a bond, wherein Y is an oxygen atom, a nitrogen atom or a sulfur atom. (H) halogenated isocyano compounds. ^{(I) R 7 - (COOH} ) m, R 8 (COX) m, R 9
^{- (COO-R 10),} R 11 -OCOO-R 12, R 13 - (
COOCO-R < ¹⁴ >) _m , or

[0019]

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Where R⁷~ R^FifteenAre the same or different
And a hydrocarbon group containing 1 to 50 carbon atoms, X is
Halogen atom, m is an integer of 1 to 5)
Rubonic acid, acid halide, ester compound, carbonate
Ter compounds or acid anhydrides. (J) R¹⁶ _lM "(OCOR¹⁷)_4-l, R¹⁸ _lM "(O
CO-R¹⁹-COOR ²⁰)_4-lOr

[0021]

Embedded image

(Wherein R ^{16 to} R ²² are the same or different and are each a hydrocarbon group having 1 to 20 carbon atoms, M ″
Is a tin atom, a silicon atom or a germanium atom, and 1 is an integer of 0 to 3).
Specific examples of the terminal modifier shown in the above (e) to (j) are described in, for example, JP-A-11-356 by the present applicant.
No. 33, paragraph numbers “0035” to “0059”, and Japanese Patent Application No. 10-59098, paragraph number “0036”.
To “0060”, and paragraphs “0036” to “0060” of Japanese Patent Application No. 11-117511. Also, the paragraph number “0” of JP-A-9-87426 is disclosed.
The alkoxysilane compounds described in "027" to "0031" can also be used as the terminal modifier.

The reaction method for modification with the above terminal modifier is as follows:
A method known per se can be used. For example, paragraph number “0060” of Japanese Patent Application No. 9-65607, paragraph number “0059” of Japanese Patent Application No. 11-117511, and paragraph number “0017” of Japanese Patent Application Laid-Open No. 7-268132. To "0027" can be adopted.

On the other hand, those used for the polymerization of a conjugated diene polymer
Known transition element catalysts should be used.
Can be. For example, (a) ′ transition element compounds,
(B) 'organoaluminum compound, (c)' alumoxa
And (d) 'a contact mainly containing a halogen-containing compound.
A medium can be used. Here, (a) ′ transition elementization
Compounds include groups 3A, 4A, 5A, and 6 in the periodic table.
Group A, Group 7A or Group 8 metal halide, carbo
Phosphate, alcoholate, thioalcoholate, amide, etc.
Is used. Also, (b) ′ organoaluminum compound
Is the same as the component (b) above,¹R^TwoR^Three
(Where R¹, R^TwoAnd R^ThreeAre the same or different
To form hydrogen or a hydrocarbon residue having 1 to 8 carbon atoms, respectively.
) Is used. (C) 'Arumoki
Sun has a structure represented by the above formula (I) or (II)
Is a compound having (D) 'a halogen-containing compound;
The same as the component (d), _nR_3-n
(Where X is halogen and R is 1 to 2 carbon atoms)
0 hydrocarbon residue, for example, alkyl group, aryl
Group, an aralkyl group, and n is 1, 1.5, 2 or
3) is t-butyl
Organic halides such as luchloride and benzyl chloride, B
F_Three・ Et_TwoAnd boron halide compounds such as O.
It is.

In particular, the use of a cobalt transition element-based catalyst as a transition element compound can be used to convert a conjugated diene polymer having a high content of 1,4-cis bonds and a low content of 1,2-vinyl bonds into an excellent polymerization activity. Is preferred. Specific examples of these transition element catalysts and polymerization conditions are described in JP-B-61-54.
No. 808, column 4, line 19 to column 6, line 18, paragraphs "0008" to "00" of JP-A-10-7717.
21 ", and paragraphs" 0010 "to" 0027 "of JP-A-11-140118.

In the present invention, secondly, after the conjugated diene-based polymer obtained above is subjected to a polymerization reaction, the polymer is left alone in an organic solvent as a polymerization solvent, or a dried polymer or a polymer from which the solvent has been removed. After adding and dissolving a new organic solvent, a necessary amount of filler is added and mixed. In the production method of the present invention, it is important to mix the filler together with the polymer in the presence of an organic solvent from the viewpoint of uniform dispersion of the filler and reactivity with the polymer.

The organic solvent used in the present invention includes butane, pentane, hexane, heptane and the like having 4 to 4 carbon atoms.
A saturated aliphatic hydrocarbon having 6 to 20 carbon atoms such as 10 saturated aliphatic hydrocarbons, cyclopentane and cyclohexane;
Monoolefins such as butene and 2-butene, aromatic hydrocarbons such as benzene, toluene and xylene, methylene chloride, chloroform, carbon tetrachloride, trichloroethylene, perchlorethylene, 1,2-dichloroethane, chlorobenzene and bromo Examples thereof include halogenated hydrocarbons such as benzene and chlorotoluene, and a mixture of these organic solvents may be used. The amount of the solvent used is usually 50 to 2,000 per 100 parts by weight of the conjugated diene polymer.
0 parts by weight, preferably 100 to 1,500 parts by weight. If the amount is less than 50 parts by weight, the viscosity of the solution becomes high, and the dispersion of the filler becomes uneven. On the other hand, if it exceeds 2,000 parts by weight, it does not act as a highly active catalyst.

The fillers used in the present invention are carbon black, silica, calcium carbonate and magnesium carbonate. Preferably, it is carbon black and / or silica. These fillers may be used as a mixture. The carbon black used is DBP
(Dibutyl phthalate) oil absorption 100-300cc
/ 100 g of carbon black is preferable, and specifically, carbon black such as FEF, HAF, ISAF, and SAF. As the silica, silica having a BET surface area of 80 to 450 m ² / g and an oil absorption of DBP (dibutyl phthalate) of 80 to 400 cc / 100 g is preferable. Further, as the silica, dry silica or wet silica is used, and preferably wet silica. The amount of the filler used is 1 to 100 parts by weight, preferably 5 to 70 parts by weight, based on 100 parts by weight of the produced polymer. If the amount is less than 1 part by weight, the reinforcing property is inferior, and the abrasion resistance and the breaking characteristics tend to be deteriorated. On the other hand, if it exceeds 100 parts by weight, the workability at the time of kneading becomes poor and the handling becomes difficult.

The mixing of the conjugated diene polymer and the filler is carried out by sufficiently reacting the polymer and the filler at a temperature of 0 to 150 ° C., preferably 20 to 100 ° C. When the above polymer is mixed with a filler, a process oil or the like can be added in the presence of an organic solvent, if necessary. Examples of the process oil that can be used in the production method of the present invention include paraffinic, naphthenic, and aromatic oils. An aromatic type is used for applications that emphasize fracture characteristics and abrasion resistance, and a naphthene type or paraffin type is used for applications that emphasize low heat generation and low temperature characteristics. The amount of process oil used is 100
It is not more than 100 parts by weight with respect to parts by weight, and if it exceeds 100 parts by weight, the resulting vulcanized rubber has significantly deteriorated breaking characteristics and low heat build-up.

After completion of the mixing with the filler and the completion of the reaction, the target rubber composition (master batch rubber composition) is treated with a known antioxidant, and a known solvent removal and drying operation in the production of a conjugated diene polymer is carried out. Can be recovered.

The rubber composition obtained by the present invention is blended with the composition alone or by blending it with another synthetic rubber or natural rubber, and comprises a vulcanizing agent, a vulcanization accelerator and other usual compounding agents. Can be added. In addition, emulsion polymerization SBR other than natural rubber, solution polymerization SBR, polyisoprene,
EP (D) M, butyl rubber, hydrogenated BR and hydrogenated SBR can be used by blending. When blended with natural rubber or other synthetic rubber, it is necessary that the master batch rubber composition of the present invention be contained in an amount of 10 parts by weight or more based on 100 parts by weight of all rubber raw materials used in the rubber composition. In order to sufficiently exert the effect of the coalescence, it is preferable that the content be at least 40 parts by weight. Also, when blended with natural rubber or other synthetic rubber,
If necessary, a filler such as carbon black or silica can be further added at the time of solid content. In that case,
With respect to 100 parts by weight of the total rubber raw material used in the rubber composition, the amount of the filler contained in the master batch rubber composition and the total amount of the filler added during kneading are 1 to 10
0 parts by weight, preferably in the range of 5 to 70 parts by weight. If the amount is less than 1 part by weight, the reinforcing properties are poor, and the abrasion resistance and the breaking characteristics tend to decrease. On the other hand, if it exceeds 100 parts by weight, the workability at the time of kneading becomes poor and handling becomes difficult.

The rubber composition of the present invention obtained as described above is subjected to vulcanization after molding, and is used for winter tires such as passenger car, truck, bus tires and studless tires, sidewalls and various members, and hoses. It is used for rubber applications that require mechanical properties, workability, and abrasion resistance, such as belts, vibration-proof rubbers, golf balls, and various other industrial products.

[0033]

EXAMPLES The present invention will be described in more detail with reference to the following Examples, which should not be construed as limiting the scope of the present invention. The percentages and parts in the examples are on a weight basis unless otherwise specified. Various measurements in the examples were performed according to the following.

Mooney viscosity (MLl + 4, 100 ° C.) Measured at a residual heat of 1 minute, a measuring time of 4 minutes and a temperature of 100 ° C. Solution Viscosity (SV ) A 5.23% toluene solution viscosity was measured at 30 ° C. using a Cannon-Fenske viscometer. It was determined by a microstructure infrared method (Morello method). Ratio between number average molecular weight (Mn) and weight average molecular weight (Mw)
(Mw / Mn) The measurement was performed using HLC-8120GPC manufactured by Tosoh Corporation under the following conditions using a differential refractometer as a detector. Column: Tosoh column GMHHXL Mobile phase: Tetrahydrofuran

Tensile strength was measured according to JIS K6301. Rebound Dunlop Ltd., using a rebound tester, to measure the value of at 50 ° C.. Using a wear-resistant Lambourn abrasion tester (manufactured by Shimada Giken Co., Ltd.)
The slip ratio was measured at room temperature at 60%.

Example 1 Anhydrous zinc chloride was placed in a three-necked flask having an inner volume of 100 ml.
(0.1 mmol) and 1-decanol (0.3
mmol) and heated to 100 ° C. to react for 2 hours.
Was. After completion of the reaction, 50 ml of toluene was added, and zinc chloride was added.
A toluene solution of the 1-decanol complex was prepared. Nitrogen storage
In a replaced 5 L autoclave, put cyclohexa under nitrogen.
2.4 kg, 300 g of 1,3-butadiene
It is. To these, versatic acid
Ojim (hereinafter "Nd (ver)_Three") (0.0
9 mmol) cyclohexane solution, methylalumoxa
(Hereinafter also referred to as “MAO”) (3.6 mmol)
Ruene solution, diisobutylaluminum hydride (hereinafter
"Al ⁱBu_TwoH ”) (3.6 mmol) and
Solution of 1-decanol complex of zinc chloride and zinc chloride (0.
09 mol) in 5 times the amount of neodymium in 1,3-butadiene
And a catalyst aged at 50 ° C. for 30 minutes.
Polymerization was performed at 60 ° C for 60 minutes. Reaction of 1,3-butadiene
The conversion was almost 100%. Measure Mooney viscosity
To this end, a part of the polymerization solution was withdrawn, coagulated and dried.
The cis-1,4 bond content is 97.0%, and the vinyl bond content is
1.0%, Mw / Mn was 2.1. Next, this weight
Keep the temperature of the combined solution at 50 ° C and use silica [VN3 (product
Name), made by Nippon Silica) 150g and stirred for 1.5 hours
Afterwards, 2,4-di-tert-butyl-p-cresol
The polymerization was terminated by adding a methanol solution containing 1.5 g of toluene.
Then, the solvent was removed by steam stripping,
And dried to obtain a polymer. Polymerization conditions and minutes
The results of the analysis are shown in Table 1.

Example 2 Anhydrous zinc chloride (0.1 mmol) was weighed into a 100 ml three-necked flask and 1-decanol (0.3 mmol) was added.
(mmol) was added dropwise, and the mixture was heated to 100 ° C and reacted for 2 hours. After the reaction was completed, 50 ml of toluene was added to prepare a toluene solution of a zinc chloride 1-decanol complex. In a 5 L autoclave purged with nitrogen, 2.4 kg of cyclohexane and 300 g of 1,3-butadiene were charged under nitrogen. In advance, as a catalyst component, a cyclohexane solution of neodymium versatate (0.09 mmol), a toluene solution of methylalumoxane (7.2 mmol),
A toluene solution (0.09 mol) of tri-2-ethylhexyl phosphate complex of diisobutylaluminum hydride (3.6 mmol) and magnesium chloride was reacted with 1,3-butadiene, which is 5 times the amount of neodymium, at 50 ° C. for 30 minutes. The catalyst was charged and polymerization was carried out at 80 ° C. for 60 minutes. The reaction conversion of 1,3-butadiene is almost 100%
Met. Next, 3-glycidyloxypropyltrimethoxysilane (2.7 mmol) was added to the polymerization solution and reacted at 80 ° C. for 30 minutes. In order to measure Mooney viscosity, a part of the polymerization solution was withdrawn, coagulated and dried. The cis-1,4-content was 97.1%, the vinyl bond amount was 1.0%, and the Mw / Mn was 2.5. Thereafter, the temperature of the polymerization solution was maintained at 50 ° C., 150 g of silica [VN3 (trade name), manufactured by Nippon Silica] was added, and the mixture was stirred for 1.5 hours, and then 2,4-di-tert-butyl-p-cresol. A methanol solution containing 5 g was added, and after the polymerization was stopped, the solvent was removed by steam stripping.
And dried to obtain a polymer. Table 1 shows the polymerization conditions and analysis results.

Example 3 A polymer was obtained in the same manner as in Example 2, except that epoxidized soybean oil was used instead of 3-glycidyloxytrimethoxysilane. Table 1 shows the polymerization conditions and analysis results.
Shown in

Example 4 A polymer was obtained in the same manner as in Example 1 except that the silica was changed to carbon black (HAF).
Table 1 shows the polymerization conditions and analysis results.

Example 5 The procedure of Example 2 was repeated except that 3-glycidyloxytrimethoxysilane was replaced by polymeric diphenylmethane diisocyanate (hereinafter also referred to as “MDI”) and silica by carbon black (HAF). A polymer was obtained in the same manner as in Example 2. Table 1 shows the polymerization conditions and analysis results.
Shown in

Example 6 In Example 2, 3-glycidyloxytrimethoxysilane was replaced with tin tetrachloride and silica was replaced with carbon black (HAF).
A polymer was obtained in the same manner as in Example 2 except that the polymer was replaced with Table 1 shows the polymerization conditions and analysis results.

Example 7 In a nitrogen-substituted 5 L autoclave, 2.4 kg of cyclohexane and 300 g of 1,3-butadiene were charged under nitrogen. To these, a cyclohexane solution of neodymium versatate (0.37 mmol) as a catalyst component, triisobutylaluminum (11.1 mmol)
, A toluene solution of diisobutylaluminum hydride (2.2 mmol) and diethylaluminum chloride (hereinafter also referred to as "DEAC")
74 mol) was mixed with 1,3-butadiene (5 times the amount of neodymium) at 50 ° C. for 30 minutes.
Polymerization was performed at 60 ° C for 60 minutes. The reaction conversion of 1,3-butadiene was almost 100%. In order to measure Mooney viscosity, a part of the polymerization solution was withdrawn, coagulated and dried.
The cis-1,4-content is 96.4%, and the vinyl bond content is 1.
2% and Mw / Mn were 2.4. Next, the temperature of the polymerization solution was maintained at 50 ° C., and silica [VN3 (trade name),
Nippon Silica] 150 g was added, and after stirring for 1.5 hours, a methanol solution containing 1.5 g of 2,4-di-tert-butyl-p-cresol was added, and after polymerization was stopped,
The solvent was removed by steam stripping and dried with a roll at 110 ° C. to obtain a polymer. Table 1 shows the polymerization conditions and analysis results.

Example 8 A nitrogen-substituted 5 L autoclave was charged with 2.4 kg of cyclohexane and 300 g of 1,3-butadiene under nitrogen. To these, a cyclohexane solution of neodymium versatate (0.37 mmol) as a catalyst component, triisobutylaluminum (11.1 mmol)
, A toluene solution of diisobutylaluminum hydride (2.2 mmol) and a toluene solution of diethylaluminum chloride (0.74 mol) were reacted with 1,3-butadiene 5 times the amount of neodymium at 50 ° C. for 30 minutes to prepare a catalyst. At 80 ° C. for 60 minutes.
The reaction conversion of 1,3-butadiene was almost 100%. Next, 3-glycidyloxypropyltrimethoxysilane (2.7 mmol) was added to the polymerization solution,
The reaction was performed at 80 ° C. for 30 minutes. In order to measure Mooney viscosity, a part of the polymerization solution was withdrawn, coagulated and dried. Mooney viscosity (ML _{1 + 4} , 100 ° C) is 44, cis-1,
4-content: 96.3%, vinyl bond amount: 1.2%, Mw
/ Mn was 2.8. Next, the temperature of the polymerization solution was kept at 50 ° C., 150 g of silica (VN3 (trade name), manufactured by Nippon Silica) was added, and the mixture was stirred for 1.5 hours, and then,
A methanol solution containing 1.5 g of -di-tert-butyl-p-cresol was added, and after terminating the polymerization, the solvent was removed by steam stripping and dried with a roll at 110 ° C to obtain a polymer. Table 1 shows the polymerization conditions and analysis results.

Comparative Example 1 A polymer was obtained in the same manner as in Example 1 except that silica was not added after completion of the polymerization. Table 1 shows the polymerization conditions and analysis results.

Comparative Example 2 A polymer was obtained in the same manner as in Example 2 except that silica was not added after completion of the polymerization. Table 1 shows the polymerization conditions and analysis results.

Comparative Example 3 A polymer was obtained in the same manner as in Example 5 except that silica was not added after completion of the polymerization. Table 1 shows the polymerization conditions and analysis results.

Comparative Example 4 A polymer was obtained in the same manner as in Example 7 except that silica was not added after the completion of the polymerization. Table 1 shows the polymerization conditions and analysis results.

Comparative Example 5 A polymer was obtained in the same manner as in Example 8, except that silica was not added after completion of the polymerization. Table 1 shows the polymerization conditions and analysis results.

Comparative Example 6 In a nitrogen-substituted 5 L autoclave, 2.4 kg of dehydrated benzene and 300 g of 1,3-butadiene were charged under nitrogen. The temperature of this mixed solution was maintained at 40 ° C., and diethylaluminum chloride (1.65 mmol), cobalt octenoate (0.22 mmol) (hereinafter referred to as “Co (Oct)
₃ ") and 1,5-cyclooctadiene (3.3 mmol), and polymerization was carried out for 60 minutes. The reaction conversion of 1,3-butadiene was 90%. A part of the polymerization solution was withdrawn, coagulated and dried. Cis-
1,4-content is 95.1%, vinyl bond amount is 3.3%,
Mw / Mn was 3.5. Next, the temperature of the polymerization solution was kept at 50 ° C., 150 g of silica (VN3 (trade name), manufactured by Nippon Silica) was added, and the mixture was stirred for 1.5 hours.
2,4-di-tert-butyl-p-cresol 1.5
A methanol solution containing g was added, and after terminating the polymerization, the solvent was removed by steam stripping and dried with a roll at 110 ° C. to obtain a polymer. Table 1 shows the polymerization conditions and analysis results.

Comparative Example 7 A polymer was obtained in the same manner as in Comparative Example 6, except that carbon black was used instead of silica. Table 1 shows the polymerization conditions and analysis results.

Comparative Example 8 Polybutadiene rubber BR01 (Moony viscosity = 45, 1,4-cis bond content = 95.0%, manufactured by JSR Corporation)
1,2-vinyl bond content = 2.5%, Mw = 670,000, M
w / Mn = 4.0) was used.

Example 9 400 g of toluene was placed in a separable flask having an inner volume of 3 L.
And 100 g of the polymer of Comparative Example 1 were charged and dissolved. After heating this solution to 50 ° C., carbon black (H
AF) A slurry solution in which 50 g was dispersed in toluene was added, and reacted at 50 ° C. for 1 hour. Next, the solvent was removed by steam stripping, and dried with a roll at 110 ° C. to obtain a polymer. Table 1 shows the analysis results.

Example 10 A polymer was obtained in the same manner as in Example 9 except that the polymer of Comparative Example 1 was replaced with the polymer of Comparative Example 3. Table 1 shows the analysis results.

Example 11 In a nitrogen-substituted 5 L autoclave, 2.4 kg of cyclohexane and 300 g of 1,3-butadiene were charged under nitrogen. Then, 1,5-cyclooctadiene (9.0
mmol) of cyclohexane, methylalumoxane (14.8 mmol) in toluene, diethylaluminum chloride (14.8 mmol) in cyclohexane, and cobalt octenoate (0.074 mmol) in cyclohexane were added in that order to bring the polymerization temperature to 60 ° C. To conduct polymerization for 1 hour. To measure Mooney viscosity,
A part of the polymerization solution was withdrawn, coagulated and dried. Cis-1,
4-content: 97.2%, vinyl bond amount: 1.7%, Mw
/ Mn was 2.2. Next, the temperature of the polymerization solution was kept at 50 ° C., 150 g of silica (VN3 (trade name), manufactured by Nippon Silica) was added, and the mixture was stirred for 1.5 hours, and then,
A methanol solution containing 1.5 g of -di-tert-butyl-p-cresol was added, and after terminating the polymerization, the solvent was removed by steam stripping and dried with a roll at 110 ° C to obtain a polymer. Table 1 shows the polymerization conditions and analysis results.

Example 12 A polymer was obtained in the same manner as in Example 11, except that carbon black was used instead of silica. Table 1 shows the analysis results.

Example 13 A nitrogen-substituted 5 L autoclave was charged with 2.4 kg of dehydrated benzene and 300 g of 1,3-butadiene under nitrogen. Further, 1.3 mmol of water was added, and for 30 minutes,
Stirred. While maintaining the temperature of the mixed solution at 40 ° C., diethyl aluminum chloride (1.65 mmol), cobalt octenoate (0.22 mmol) and 1,5-cyclooctadiene (3.3 mmol) were added, and the polymerization was carried out for 60 minutes. went. The reaction conversion of 1,3-butadiene was 90%. Withdraw part of the polymerization solution, coagulate,
Dried. The cis-1,4-content was 96.3%, the amount of vinyl bond was 1.8%, and Mw / Mn was 2.3. next,
The temperature of the polymerization solution was maintained at 50 ° C., and silica [VN3
(Trade name, manufactured by Nippon Silica), 150 g was added, and the mixture was stirred for one and a half hours, and then 2,4-di-tert-butyl-p-
A methanol solution containing 1.5 g of cresol was added, and after terminating the polymerization, the solvent was removed by steam stripping.
The polymer was dried with a roll at 10 ° C. to obtain a polymer. Table 1 shows the polymerization conditions and analysis results.

Example 14 A polymer was obtained in the same manner as in Example 13, except that carbon black was used instead of silica. Table 1 shows the analysis results.

[0058]

[Table 1]

Next, using the rubber compositions obtained in Examples 1 to 3 and 7 to 8 and the rubbers of Comparative Examples 1 to 2 and 4 to 6 and 8,
According to the following formulation, kneading and blending were performed using a plastmill. Press vulcanization was performed at 145 ° C. for an optimum time. In Comparative Examples 1 to 2, Comparative Examples 4 to 6, and Comparative Example 8 (BR01), 50 parts of silica (VN-3) was added at the time of kneading. Tables 2 and 3 show the physical properties of the obtained vulcanized rubber. Formulation (part ) Polymer + silica 150 Aroma oil 15 Zinc flower 3 Stearic acid 2 Antioxidant (* 1) 1 Vulcanization accelerator (* 2) 0.8 Sulfur 1.5 * 1) N-isopropyl-N ' -Phenyl-p-phenylenediamine * 2) N-cyclohexyl-2-benzothiazylsulfenamide

[0060]

[Table 2]

[0061]

[Table 3]

* 1) A commercially available BR (JSR) manufactured by JSR Corporation
BR01) * 2) Comparative Example 8 was set to 100, and the larger the numerical value, the better. From Tables 2 and 3, Examples 1 to 3 and 7 to 8 were Comparative Examples 1 to 3.
2, it is understood that a rubber composition having excellent breaking strength, rebound resilience and abrasion resistance is provided for Comparative Examples 4 to 6 and Comparative Example 8. Comparing Example 1 with Comparative Example 1 and Example 2 with Comparative Example 2, it can be seen that the Mooney viscosities of the blends are almost the same, and that the processability is not impaired by converting the silica into a masterbatch. From Example 1 and Comparative Example 2, even if the polymer was not modified, the rubber composition was prepared by converting silica into a master batch, and then the rubber composition prepared by simultaneously kneading the terminal-modified polymer and silica. It can be seen that vulcanization properties equivalent to those obtained were obtained. Examples 2 and 3 show that when a rubber composition is prepared after converting the terminal-modified polymer into a master batch with silica, the vulcanization properties are further improved. Also, from Examples 7 and 8, regardless of the catalyst system,
When the polymer is made into a masterbatch with silica, the vulcanization properties are improved, and when the terminal-modified polymer is used, the properties are further improved.

Next, the rubber compositions obtained in Examples 4 to 6, 9 to 10 and Comparative Examples 1, 3 and 7, 8 [polybutadiene rubber BR0 manufactured by JSR Corporation]
Using [1], kneading and blending were performed using a plastmill according to the blending recipe shown below. Press vulcanization was performed at 145 ° C. for an optimum time. In Comparative Examples 1 and 3, and Comparative Examples 7 and 8 (BR01), 50 parts of HAF carbon black was added during kneading. Table 3 shows the physical properties of the obtained vulcanized rubber. Formulation (part ) Polymer 50 Aroma oil 15 Zinc white flower 3 Stearic acid 2 Antioxidant (* 1) 1 Vulcanization accelerator (* 2) 0.8 Sulfur 1.5 * 1) N-isopropyl-N'-phenyl -P-phenylenediamine * 2) N-cyclohexyl-2-benzothiazylsulfenamide

[0064]

[Table 4]

[0065]

[Table 5]

* 1) A commercially available BR (JSR) manufactured by JSR Corporation
BR01) * 2) Comparative Example 8 was set to 100, and the larger the numerical value, the better. From Tables 4 to 5, Examples 4 to 6, 9 to 10 are Comparative Examples 1 and 2.
It can be seen that a rubber composition having excellent breaking strength, rebound resilience and abrasion resistance is given to 3, 7 to 8. It can be seen that the physical properties are improved when carbon black is formed into a masterbatch with a polymer similarly to silica. Examples 5 to 6
It can be seen that the use of the terminal-modified polymer further improves the physical properties. Further, from Examples 9 to 10, it can be seen that the physical properties are improved even if the polymer is redissolved in a solvent and then made into a masterbatch with carbon black.

[0067]

The method for producing a rubber composition of the present invention can be widely used industrially because it provides a rubber composition having excellent breaking characteristics, low heat build-up and abrasion resistance.

Claims (3)

[Claims] 1. A 1,4-cis bond content of 85% or more,
The 1,2-vinyl bond content is 2.0% or less, and the ratio of the weight average molecular weight (Mw) to the number average molecular weight (Mn) (Mw / M
n) is 3.5 or less, and the Mooney viscosity (ML _{1 + 4} , 100
C.) is 10 to 70, and the ratio (SV) between the solution viscosity (SV) and the Mooney viscosity (MV) measured in toluene at 25 ° C.
A method for producing a rubber composition, comprising mixing a conjugated diene-based polymer having an (MV) of 2 to 15 with an filler in a state of being dissolved in an organic solvent. 2. The method for producing a rubber composition according to claim 1, wherein the conjugated diene-based polymer is a polymer having a terminal modified. 3. The method for producing a rubber composition according to claim 1, wherein the filler is carbon black and / or silica.