JP2000344955A - Modified diene-based rubber composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a modified diene-based rubber composition excellent in rolling friction-resisting characteristics, grip performance and wear resistance. SOLUTION: This modified diene-based rubber composition comprises compounding a rubber component containing 10-80 wt.% of a modified diene- based rubber in an amount of 100 pts.wt. with silica in an amount of 5-100 pts.wt. and a silane coupling agent in an amount of 0-10 wt.% based on weight of the silica, wherein the modified diene-based rubber is formed by polymerizing a diolefin having conjugated double bonds by the use of a catalyst comprising (A) a cobalt compound, (B) an organoaluminum compound and (C) water to form a diene-based rubber and subsequently modifying the formed diene-based rubber by the use of an organosilicon compound containing amino and alkoxyl groups as a modifying agent so that not less than 80% of repeating units of the modified diene-based rubber comprise a cis-1,4 form, and the modified diene- based rubber has a weight-average molecular weight(Mw) of 20, 000-1,000,000 according to gel permeation chromatography(GPC) and contains nitrogen, which is derived from the modifying agent, in an amount of >=10 ppm.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a rolling friction resistance characteristic (fuel consumption) comprising a modified diene rubber obtained by modifying a rubber having a high cis-1,4 structure with an organosilicon compound containing an amino group and an alkoxy group. The present invention relates to a modified diene rubber composition having excellent grip characteristics such as wet skid characteristics and wet-on-ice characteristics (performance on snow and ice) and friction resistance.

[0002]

2. Description of the Related Art Conventionally, rubbers for automobile tires include polybutadiene rubber (BR), natural rubber (NR),
Styrene-butadiene rubber (SBR) and the like are used.

In recent years, there has been an increasing demand for low fuel consumption of automobiles and a demand for running safety on rainy weather, on snow and on ice, and as a tire tread rubber for automobiles, the rolling resistance at high temperatures is small, and on rainy weather, on snow and on ice. It has been desired to develop a material having a large road grip.

However, rubber having high rebound resilience (small rolling resistance) such as BR has low wet skid resistance, and rubber having low resilience (high rolling resistance) such as SBR has high wet skid resistance. These are characteristics that are mutually exclusive. Therefore, how to maintain these characteristic values in a well-balanced manner and improve both characteristic values has been an issue.

Hitherto, as a means for solving such a problem, many methods have been proposed for chemically modifying a low cis-conjugated diene rubber obtained using a lithium catalyst with a modifier.

For example, a method of modifying a low cis BR with a benzophenone compound has been proposed in JP-A-58-162604 and JP-A-59-117514, in which the rolling resistance of an automobile tire is small and a wet skid is provided. An improvement effect of increasing resistance has been recognized.

Further, a low cis BR produced with a lithium catalyst is used.
Is reacted with a silicon or tin compound and a specific aminosilane compound to produce a modified diene rubber, which is disclosed in JP-A-1-284503.
It is described that it has high rebound resilience, low JIS hardness at low temperature, and excellent workability.

However, a low cis BR is a high cis BR
As compared with the above, the abrasion resistance and rebound resilience are insufficient, and this problem cannot be solved even by modification.

The low cis BR obtained by using a lithium catalyst is in a state where the terminal of the polymer is activated (living state) and easily reacts with a modifying agent. The high cis BR produced by the above catalyst has poor reactivity and is difficult to react with a modifier. Therefore, there have been few proposals on modification methods for rubbers having a high cis-1,4 structure.

On the other hand, in recent years, from the viewpoint of reinforcing properties, many methods have been reported in which silica is used as a filler for reducing heat generation. However, silica particles aggregate due to hydrogen bonds of silanol groups, which are surface functional groups. Therefore, various silane coupling agents have been developed to solve these problems. However, this silane coupling agent is still insufficient to raise the workability and processability of the rubber composition to a high level, although the cost is high.

[0011]

DISCLOSURE OF THE INVENTION The present invention relates to a modified diene rubber which is excellent in gripping properties such as rolling friction resistance properties (fuel consumption properties), wet skid properties and wet-on-ice properties (performance on snow and ice) and friction resistance. It is intended to provide a composition.

[0012]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to improve the above-mentioned problems, and as a result, have found that a rubber having a high cis-1,4 structure can be converted into a silicon compound containing amino groups and alkoxy groups. The modified diene rubber composition composed of the modified diene rubber modified by the above has grip characteristics such as rolling friction resistance characteristics (fuel consumption characteristics), wet skid characteristics and wet on ice characteristics (performance on snow and ice) and friction resistance. And completed the present invention.

That is, the present invention provides a diene rubber obtained by polymerizing a diolefin having a conjugated double bond using a catalyst comprising (A) a cobalt compound, (B) an organoaluminum compound and (C) water. Was modified using an organosilicon compound containing an amino group and an alkoxy group as a modifier, wherein 80% or more of the repeating units were cis-1,
It has 4 structures, a weight average molecular weight (Mw) by GPC of 20,000 to 1,000,000, and contains 10 to 80% by weight of a modified diene rubber having a nitrogen content of 10 ppm or more due to a modifier. The present invention relates to a modified diene rubber composition (Claim 1) in which 5 to 100 parts by weight of silica and 0 to 10% by weight of silica are blended with respect to 100 parts by weight of a rubber component.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION The modified diene rubber used in the present invention is a diolefin having a conjugated double bond using a catalyst comprising (A) a cobalt compound, (B) an organoaluminum compound and (C) water. 80% obtained by polymerizing
The above is a diene rubber having a cis-1,4 structure modified using an organosilicon compound containing an amino group and an alkoxy group as a modifier.

The diolefin having a conjugated double bond can be used without particular limitation as long as it is generally used as a raw material monomer for diene rubber. Specifically, polybutadiene rubber, styrene-butadiene rubber, styrene-isoprene-butadiene rubber and the like are preferable as the diene rubber,
1,3-butadiene, isoprene and the like are preferably used. These may be used alone or in combination of two or more. In addition, styrene is preferably used as a copolymer component.

The polymerization of the diolefin is generally carried out in the polymerization solvent using the catalyst. The polymerization conditions are not particularly limited, and may be general conditions known to those skilled in the art.

Examples of the polymerization solvent include inert aromatic hydrocarbons, aliphatic hydrocarbons and alicyclic hydrocarbons. Specifically, benzene, toluene, xylene, n-hexane, n-pentane, n-heptane, n-
Octane, cyclohexane, methylcyclohexane, decalin and the like. These may be used alone or in combination of two or more.

The cobalt compound which is the component (A) of the catalyst used in the present invention includes organic cobalt carboxylate, cobalt organic sulfonate, β-diketone complex compound of cobalt, and tertiary amine complex compound of cobalt halide. Are used. Specifically, cobalt naphthenate, cobalt octenoate, cobalt malonate, cobalt octoate, cobalt stearate, cobalt acetate, cobalt benzoate, cobalt oxalate, cobalt salicylate,
Cobalt dodecylbenzenesulfonate, bis (ethyl acetoacetate) cobalt, bis (acetylacetonato) cobalt, tris (acetylacetonato) cobalt, dichloro-bis (pyridine) cobalt and the like can be mentioned.
These may be used alone or in combination of two or more. Among these, organic cobalt carboxylate, especially cobalt naphthenate, cobalt octenoate,
Cobalt octoate is preferred.

The organoaluminum compound which is the component (B) of the catalyst used in the present invention is represented by the general formula Al
R ₂ X (where R represents an alkyl group having 1 to 6 carbon atoms such as an ethyl group, an isobutyl group and a hexyl group, and the two alkyl groups may be the same or different; X represents a chlorine atom, a bromine atom, (Indicates halogen atom such as iodine atom)
Are represented by Specifically, diethyl aluminum monochloride, diisobutyl aluminum monochloride, dihexyl aluminum monochloride,
And diethyl aluminum monobromide. These may be used alone or in combination of two or more. Of these, diethyl aluminum monochloride and diisobutyl aluminum monochloride are preferably used.

The amount of the cobalt compound to be used is preferably 1 × 10 ^-7 to 1 × 10 ^-3 mol per 1 mol of the diolefin.

The amount of the organoaluminum compound used is:
1 × 10 ⁻⁵ to 1 × 10 per 1 mol of the diolefin
^-1 mole is preferred.

The amount of the water used is preferably 1 × 10 ^-5 to 1 × 10 ^-1 mol per 1 mol of the diolefin. When the amount of water added is less than 1 × 10 ^-5 mol, the effect of improving the catalyst activity is small, and when it exceeds 1 × 10 ^-1 mol, the activity decreases.

There are no particular restrictions on the order in which the catalyst components are added, but it is desirable that the organoaluminum compound and water be reacted beforehand before addition.

The diene rubber is modified with an organosilicon compound containing an amino group and an alkoxy group.
Preferably, it is modified immediately after production. Here, "immediately after production" means that the modification is continuously performed in a polymerization system in which a diolefin rubber is obtained by polymerization of a diolefin. In this case, the modification may be performed by directly adding a modifying agent to the polymerization system from which the diene rubber was obtained. The temperature at which denaturation is performed is preferably in the range of 0 to 100 ° C, more preferably in the range of room temperature to 70 ° C. If the temperature is too low, the modification reaction hardly proceeds, and if the temperature is too high, the diene rubber gels, which is not preferable. The denaturation reaction time is not particularly limited, but is preferably in the range of 0.5 to 6 hours. If the denaturation time is too short, the reaction does not proceed sufficiently, and if the time is too long, the diene rubber may gel, which is not preferable.

The modifier may be any organosilicon compound containing an amino group and an alkoxy group such as a methoxy group, an ethoxy group, a propoxy group and a butoxy group in the molecule, and is not particularly limited. Specifically, 3-aminopropyldimethylmethoxysilane, 3-aminopropylmethyldimethoxysilane, 3-aminopropylethyldimethoxysilane, 3-aminopropyltrimethoxysilane,
3-aminopropyldimethylethoxysilane, 3-aminopropylmethyldiethoxysilane, 3-aminopropyltriethoxysilane, 3-aminopropyldimethylbutoxysilane, 3-aminopropylmethyldibutoxysilane, 3- (2-aminoethylamino Propyl) dimethoxymethylsilane, 3- (2-aminoethylaminopropyl) dimethoxyethylsilane, 3- (2-aminoethylaminopropyl) dimethoxypropylsilane, 3-
(2-aminoethylaminopropyl) dimethoxybutylsilane, 3- (2-aminoethylaminopropyl) diethoxymethylsilane, 3- (2-aminoethylaminopropyl) trimethoxysilane, 3- (2-aminoethylaminopropyl ) Triethoxysilane, 3- (2-aminoethylaminopropyl) tributoxysilane and the like. These may be used alone or in combination of two or more. Of these, especially 3
-Aminopropyltrimethoxysilane, 3- (2-aminoethylaminopropyl) dimethoxymethylsilane, 3
-(2-Aminoethylaminopropyl) trimethoxysilane is preferably used.

The amount of the modifier to be used is as follows:
0.01 to 150 mmol, more preferably 1.
0-100 mmol is preferred. If the amount of the modifying agent is small, the amount (modified amount) of the silicon compound containing an amino group and an alkoxysilyl group introduced into the modified diene rubber becomes small, and a satisfactory modifying effect is hardly exhibited.
On the other hand, if the amount of the modifying agent is too large, unreacted modifying agent remains in the modified diene rubber, and it takes time to remove the modifying agent. Hard to appear.

It is considered that the modifier is bonded to a double bond and / or a 1,2-vinyl group and / or a terminal of the main chain.

The modified diene rubber preferably has a cis-1,4 structure in which at least 80%, more preferably at least 85%, of its repeating units.

The modified diene rubber has a GP
The weight average molecular weight (Mw) by C (gel permeation method) is preferably from 20,000 to 1,000,000, and more preferably from 100,000 to 1,000,000. When the weight average molecular weight is less than 20,000,
When the strength becomes low and exceeds 1,000,000, the workability is reduced. Further, the molecular weight distribution (Mw / number average molecular weight (Mn)) is preferably 1 to 3. For the same reason, Mooney viscosity (ML _{1 + 4} , 100 ° C.)
It is preferably from 20 to 80.

The fact that the diene rubber has been chemically modified is confirmed by measuring the nitrogen content of the modified diene rubber from which the unreacted modifier has been sufficiently removed by the Kjeldahl method described later. Can be. The nitrogen content is
This is an index indicating how much the diene rubber and the modifier have reacted. Even if the content of the nitrogen atom is very small, easy and reliable analysis is possible, and the modification ratio of the modified diene rubber can be evaluated based on the nitrogen content.

The nitrogen content of the modified diene rubber is as follows:
It is preferably 10 ppm or more, more preferably 10 to 5,000 ppm. When the nitrogen content is less than 10 ppm, the effect due to the modification of the diene rubber decreases, and
If it exceeds 00 ppm, gelation of the rubber during kneading is promoted, and the processability tends to deteriorate.

The modified diene rubber may be used alone or in combination of two or more. The modified diene rubber is used by being blended with another synthetic rubber or natural rubber.However, the effect of using the modified diene rubber is sufficiently obtained. The amount is from 10 to 80% by weight, preferably from 15 to
75% by weight. If necessary, it may be used after being oil-extended with process oil.

Examples of the other synthetic rubbers include unmodified diene rubbers such as styrene-butadiene rubber, polyisoprene rubber, styrene-isoprene-butadiene rubber, ethylene-propylene-diene rubber, chloroprene rubber, acrylonitrile-butadiene rubber. And so on.

The silica used in the rubber composition of the present invention is not particularly limited, and examples thereof include dry silica (silicic anhydride) and wet silica (hydrous silicic acid), with wet silica being preferred. In addition, nitrogen adsorption specific surface area (N ₂ S
Those having A) of 50 to 300 m ² / g are preferred. When the nitrogen adsorption specific surface area (N ₂ SA) of silica is less than 50 m ² / g, the dispersibility improving effect and the reinforcing effect tend to be small, and when it exceeds 300 m ² / g, dispersibility becomes poor and heat generation increases Tend to. Preferred examples of the wet process silica include Ultrasil VN3 (trade name) manufactured by Degussa Corporation and Nip Seal VN3 AQ manufactured by Nippon Silica Co., Ltd.
(Product name).

The amount of silica is 5 to 100 parts by weight, preferably 10 to 85 parts by weight, per 100 parts by weight of the rubber component.
Parts by weight, more preferably 20 to 65 parts by weight. If the amount of silica is less than 5 parts by weight, the reinforcing effect is small,
If it exceeds 100 parts by weight, the workability is undesirably reduced. The amount of silica is preferably 20 to 65 parts by weight from the viewpoint of low heat generation and workability.

The silane coupling agent used in the rubber composition of the present invention has the effect of strengthening the bond between silica and the rubber component and improving wear resistance. As the silane coupling agent, any silane coupling agent conventionally used in combination with silica may be used. Specifically, bis (3-triethoxysilylpropyl) tetrasulfide, bis (2-triethoxysilylethyl) tetrasulfide, bis (3-trimethoxysilylpropyl) tetrasulfide, bis (2-trimethoxysilylethyl)
Tetrasulfide, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, 2-mercaptoethyltrimethoxysilane, 2-mercaptoethyltriethoxysilane, 3-nitropropyltrimethoxysilane, 3-nitropropyltriethoxysilane , 3-chloropropyltrimethoxysilane, 3
-Chloropropyltriethoxysilane, 2-chloroethyltrimethoxysilane, 2-chloroethyltriethoxysilane, 3-trimethoxysilylpropyl-N, N-dimethylthiocarbamoyltetrasulfide, 3-triethoxysilylpropyl-N, N -Dimethylthiocarbamoyltetrasulfide, 2-triethoxysilylethyl-N, N-dimethylthiocarbamoyltetrasulfide, 3-trimethoxysilylpropylbenzothiazoletetrasulfide, 3-triethoxysilylpropylbenzothiazoletetrasulfide, 3-triethoxy Silylpropyl methacrylate monosulfide, 3-trimethoxysilylpropyl methacrylate monosulfide and the like can be mentioned. Bis (3-triethoxysilylpropyl) tetrasulfide or the like is preferable from the viewpoint of achieving both the effect of adding the coupling agent and the cost.

The amount of the silane coupling agent is from 0 to 10% by weight, preferably from 0.5 to 8%, based on the weight of the silica.
% By weight is preferred. The amount of the silane coupling agent is 1
If the amount exceeds 0% by weight, the coupling effect cannot be obtained in spite of the increased cost, which is not preferable. From the viewpoint that the dispersibility of silica and the coupling effect can be obtained, the amount of the silane coupling agent is preferably 0.5 to 8% by weight.

Further, the rubber composition of the present invention has a nitrogen adsorption specific surface area (N ₂ SA) of 30 to 200 m ² / g and a compressed dibutyl phthalate oil absorption (24M4DBP oil absorption) of 30 to 200 m ² / g.
It may contain carbon black in the range of 150 ml / 100 g. When the nitrogen adsorption specific surface area (N ₂ SA) and the compressed dibutyl phthalate oil absorption (24M4DBP oil absorption) are smaller than the respective lower limits, the dispersibility improving effect and the reinforcing effect are small, and when exceeding the upper limits,
Dispersibility is poor, and heat generation tends to increase. Examples of carbon black that can be used include HAF, ISA
F, SAF and the like.

In addition to the rubber component, silica, silane coupling agent and carbon black, the rubber composition of the present invention may further contain, if necessary, a softener, an antioxidant, a vulcanizing agent, a vulcanization accelerator. A compounding agent used in the ordinary rubber industry, such as a vulcanization accelerator, can be appropriately compounded, and a tire,
It is applied as a rubber composition requiring mechanical properties and abrasion resistance of hoses, belts and other various industrial products.

[0040]

EXAMPLES Hereinafter, the present invention will be described specifically with reference to Examples, but these do not limit the purpose of the present invention. First, various chemicals used in the following Examples and Comparative Examples will be described below.

(Explanation of Various Chemicals) Natural rubber: NR 7 silica: Ultrasil VN3 (N ₂ manufactured by Degussa)
(SA: 180 m ² / g) Silane coupling agent: Si69 (chemical name: bis (3-triethoxysilylpropyl) tetrasulfide) manufactured by Degussa Vulcanization accelerator A: Noxeller N manufactured by Ouchi Shinko Chemical Co., Ltd.
S (chemical name: Nt-butyl-2-benzothiazyl sulfenamide) Vulcanization accelerator B: Noxeller D manufactured by Ouchi Shinko Chemical Co., Ltd.
(Chemical name: N, N'-diphenyl guanidine) The cis-1,4 structure amount, weight average molecular weight and molecular weight distribution, nitrogen content and Mooney viscosity of the rubber component were measured by the following methods.

(Cis-1,4 structure amount) By measuring the microstructure of the rubber using a 0.4% by weight carbon disulfide solution by infrared absorption spectroscopy,
The 1,4 structure amount was calculated.

(Weight average molecular weight and molecular weight distribution) Gel permeation (permeation) chromatography (manufactured by Tosoh Corporation, GPC) using polystyrene as a standard substance and tetrahydrofuran as a solvent at a temperature of 40 ° C. was performed, and the obtained molecular weight was obtained. The weight average molecular weight (Mw) and the number average molecular weight (Mn) were determined using a calibration curve determined from the distribution curve. The molecular weight distribution was calculated as a ratio (Mw / Mn) between the weight average molecular weight (Mw) and the number average molecular weight (Mn).

(Nitrogen content) It was quantified by the Kjeldahl method according to JIS K0102.

(Mooney viscosity (ML _{1 + 4} , 100 ° C.))
After preheating at 100 ° C. for 1 minute according to JIS K6300, the rubber Mooney viscosity (ML) measured for 4 minutes
_{1 + 4} , 100 ° C).

In the following Examples and Comparative Examples, the tensile strength (M300), Lambourn abrasion index, rolling resistance index and wet skid index of the rubber composition were measured by the following methods.

(Tensile test) Measured according to JIS K6301 and indicated as a modulus of 300%.

(Rolling Resistance Index) Using a viscoelastic spectrometer VES (manufactured by Iwamoto Seisakusho Co., Ltd.) at a temperature of 7
The tan δ of each composition was measured under the measurement conditions of 0 ° C., an initial strain of 10%, and a dynamic strain of 2%. The larger the index, the better the rolling resistance characteristics. Rolling resistance index = (tan δ of Comparative Example 1 / ta of each formulation)
nδ) × 100

(Lambourn abrasion index) Using a Lambourn abrasion tester, the Lambourn abrasion was measured under the conditions of a temperature of 20 ° C., a slip ratio of 20%, and a test time of 5 minutes, and the volume loss of each composition was calculated and compared. The loss amount of Example 1 was set to 100, and an index was expressed by the following formula. A larger index indicates better wear resistance. Wear index = (Loss of Comparative Example 1 / Loss of each compound) × 1
00

(Wet skid index) ASTM E3 using a portable squid tester manufactured by Stanley
It was measured according to the method of 03-83 and expressed as an index by the following formula. The larger the index, the better the wet skid performance.

Wet skid index = (numerical value of each formulation /
Next, the rubber component will be described.

Production Example 1 In a 1.5 L stainless steel autoclave whose inside was sufficiently purged with nitrogen, 1 L of a benzene-C ₄ fraction mixed solution containing 27.9% by weight of 1,3-butadiene (benzene 26.
9 wt% and cis-2-butene containing 45.2 wt% of C ₄ fraction as a main component) were charged, then, distilled water 2 mmol, diethylaluminum monochloride (n- hexane solution) 2.9 mmol Was added and the mixture was stirred. Next, 4.24 mmol of cyclooctadiene was added, and the temperature of the autoclave was raised. After the internal temperature reached 58.5 ° C, the polymerization of 1,3-butadiene was started by injecting 0.0087 mmol of cobalt octenoate (benzene solution) as a main catalyst, and the temperature was increased to 30 ° C at 60 ° C.
The polymerization reaction was performed for minutes.

After the completion of the polymerization reaction, the unreacted gas is discharged out of the system, and 500 ml of toluene is added.
After making a toluene solution of unmodified polybutadiene, 500 ml of methanol was further added, and the contents were sufficiently stirred for 10 minutes. After the stirring was stopped, the entire contents of the autoclave were transferred to another container, and the unmodified polybutadiene was filtered and separated. After dissolving the separated polymer in 800 ml of toluene, 800 ml of methanol was added to precipitate the polymer, and the operation of filtration and separation was repeated three times. Next, Irganox 1010 was used as an antioxidant for the unmodified polymer.
(Tetrakis (methylene-3- (3 ', 5'-di-t
0.11 phr of -butyl-4'-hydroxyphenyl) propionate) methane, 0.45 phr of trisnonylphenyl phosphite as an antioxidant were added and kneaded, followed by vacuum drying at 100 ° C. for 1.5 hours. , Unmodified polybutadiene (hereinafter referred to as polymer 1)
Manufactured).

Using the obtained polymer 1, cis-1,4
The structure amount, weight average molecular weight and molecular weight distribution, nitrogen content and Mooney viscosity were measured. Table 1 shows the results.

Production Example 2 In a 1.5 L stainless steel autoclave whose inside was sufficiently purged with nitrogen, 1 L of a benzene-C ₄ fraction mixed solution containing 27.9% by weight of 1,3-butadiene (benzene 26.
9 includes by weight% and C ₄ fraction 45.2% by weight consisting primarily of cis-2-butene) were charged, and then distilled water 2 mmol, diethylaluminum monochloride (n- hexane) 2.9 mmol of In addition, stirring was performed. Next, 4.24 mmol of cyclooctadiene was added, and the temperature of the autoclave was raised. After the internal temperature reached 58.5 ° C, the polymerization of 1,3-butadiene was started by injecting 0.0087 mmol of cobalt octenoate (benzene solution) as a main catalyst, and the temperature was increased to 30 ° C at 60 ° C.
The polymerization reaction was performed for minutes.

Immediately after the completion of the polymerization reaction, at the same temperature, 1.78 mmol of 3- (2-aminoethylaminopropyl) trimethoxysilane as a modifier was added to 100 g of rubber, and the modification reaction was carried out for 120 minutes. Was.

After completion of the denaturation reaction, the unreacted gas is discharged out of the system, and 500 ml of toluene is added.
After making the modified polybutadiene solution in toluene, 500 ml of methanol was further added, and the contents were sufficiently stirred for 10 minutes. After stopping the stirring, transfer the entire content of the autoclave to another container, and filter the modified polybutadiene.
separated. The separated polymer was dissolved in 800 ml of toluene, and then 800 ml of methanol was added to precipitate the polymer, followed by filtration and separation three times. Next, 0.11 phr of Irganox 1010 (tetrakis- (methylene-3- (3 ′, 5′-di-tert-butyl-4′-hydroxyphenyl) propionate) methane) as an antioxidant was added to the modified polymer. A modified polybutadiene (hereinafter referred to as polymer 2) was produced by adding and kneading 0.45 phr of trisnonylphenyl phosphite as an antioxidant, followed by vacuum drying at 100 ° C. for 1.5 hours.

Using the obtained polymer 2, cis-1,4
The structure amount, weight average molecular weight and molecular weight distribution, nitrogen content and Mooney viscosity were measured. Table 1 shows the results.

Production Example 3 A modified polybutadiene (hereinafter referred to as polymer 3) was prepared in the same manner as in polymer 2, except that the modifier was changed to 3- (2-aminoethylaminopropyl) dimethoxymethylsilane.
Was manufactured.

Using the obtained polymer 3, cis-1,4
The structure amount, weight average molecular weight and molecular weight distribution, nitrogen content and Mooney viscosity were measured. Table 1 shows the results.

Production Example 4 A modified polybutadiene (hereinafter referred to as Polymer 4) was produced in the same manner as in Polymer 2, except that the modifier was changed to 3-aminopropyltrimethoxysilane.

Using the obtained polymer 4, cis-1,4
The structure amount, weight average molecular weight and molecular weight distribution, nitrogen content and Mooney viscosity were measured. Table 1 shows the results.

Production Example 5 3- (2-aminoethylaminopropyl) as a modifier
A modified polybutadiene (hereinafter, referred to as polymer 5) was produced in the same manner as in polymer 2, except that the amount of trimethoxysilane was changed to 0.95 mmol.

Using the obtained polymer 5, cis-1,4
The structure amount, weight average molecular weight and molecular weight distribution, nitrogen content and Mooney viscosity were measured. Table 1 shows the results.

[0065]

[Table 1]

Examples 1 to 5 and Comparative Examples 1 and 2 The compositions shown in Table 2 were used as the basic composition.

Using a 60 cc Banbury-type plastmill, a composition having a main composition shown in Table 3 (see Table 2 for components of sawdust) was kneaded (vulcanizing agent was kneaded using a roll). Press vulcanization at 150 ° C. for 30 minutes to prepare various rubber compositions, tensile strength (M300),
The Lambourn abrasion index, rolling resistance index and wet skid index were measured. Table 3 shows the results.

[0068]

[Table 2]

[0069]

[Table 3]

[0070]

According to the present invention, the rolling friction resistance characteristic (fuel consumption) of a modified diene rubber obtained by modifying a rubber having a high cis-1,4 structure with an organosilicon compound containing an amino group and an alkoxy group is provided. Characteristics), wet skid characteristics and wet-on-ice characteristics (performance on snow and ice) and a modified diene rubber composition having excellent friction resistance.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C08K 3/36 C08K 3/36 5/541 5/54 (72) Inventor Atsushi Inoue Goi Minami, Ichihara-shi, Chiba Eighth coast, Ube Industries, Ltd. Chiba Petrochemical Factory (72) Inventor Tetsuji Nakajima Eighth, Goi south coast, Ichihara City, Chiba Prefecture Eighth Ube Industries, Ltd. Chiba Petrochemical Factory F-term (reference) 4J002 AC02W AC06W AC07W AC08W AC09W AC11X BB15W BC05W CP17X DJ016 FB096 GN01 4J028 AA01A AB00A AC47A BA00A BB00A BB01B BC14B BC16B EB12 EB13 EB14 FA02 GA01 GA06 GA11 GA26 4J100 AA02 CA03 CA02 AS03A02 AS03A02 AS03A02

Claims (1)

[Claims] 1. A catalyst comprising (A) a cobalt compound, (B) an organoaluminum compound and (C) water,
A diene rubber obtained by polymerizing a diolefin having a conjugated double bond is modified with an organosilicon compound containing an amino group and an alkoxy group as a modifier, and 80% or more of the repeating units are cis. -1, 4 structure, GP
The weight average molecular weight (Mw) by C is from 20,000 to 1,
100,000 parts by weight of a rubber component containing 10 to 80% by weight of a modified diene rubber having a nitrogen content of 10 ppm or more,
A modified diene rubber composition comprising 00 parts by weight and a silane coupling agent in an amount of 0 to 10% by weight based on the weight of silica.