JP2002356583A - Method for producing rubber composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a dien-rubber composition having excellent processability in a silica formulation and improve in a balance between low rolling resistance, wet skid resistance, strength characteristic. SOLUTION: This method for producing a rubber composition containing reinforcing silica comprises the steps of obtaining a rubber composition containing reinforcing silica by (1) a first kneading and (2) a second kneading, adding total amount of (D) a vulcanizer and a vulcanizing accelerator kneading at the kneading/discharging temperature of 120 deg.C or lower, cooling to obtain a vulcanizable composition and vulcanizing at the temperature of 130 to 200 deg.C is performed. The rubber composition to be vulcanized comprises (A-1) 100 pts.wt. raw material rubber comprising a dien-rubber having a modified group compatible with reinforcing silica, (B-1) 25 to 150 pts.wt. reinforcing silica filler, (C) 0.1 to 15 pts.wt. silane coupling agent, and (D) 1.0 to 20 pts.wt. total of vulcanizer and vulcanizing accelerator.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention provides a rubber composition containing a conjugated diene rubber having improved processability, and further excellent hysteresis loss characteristics and strength characteristics, and a reinforcing silica as a filler. About the method. More specifically, the present invention relates to a method for preparing a rubber containing a diene-based rubbery polymer having a modifying group having an affinity for reinforcing silica (hereinafter, may be simply referred to as a modifying group) with a reinforcing silica under specific conditions. By kneading, it is possible to further enhance the reaction between the reinforcing silica and the modifying group in the rubber, and to obtain a rubber composition having excellent processability and good hysteresis loss characteristics which cannot be obtained by the conventional kneading method. And a method for producing a rubber composition. The composition obtained by the method is suitably used for applications where a conjugated diene polymer rubber composition has been conventionally used, mainly for tires.

[0002]

2. Description of the Related Art In recent years, in addition to resource saving and energy saving, social demands for reduction of carbon dioxide emission from the standpoint of environmental protection have increased. Various measures are being considered for automobiles, such as reducing the weight of automobiles and using electric energy, with the aim of reducing carbon dioxide emissions.A common issue for automobiles is improving fuel efficiency by improving rolling resistance of tires Is needed. At the same time, there is a growing demand for automobiles to improve driving safety. The fuel efficiency and safety of these vehicles largely depend on the performance of the tires to be used, and there is an increasing demand for tires for vehicles to improve fuel efficiency, steering stability and durability. The characteristics of these tires depend on various factors such as the structure and materials of the tire, but the performance of the rubber composition used for the tread portion in contact with the road surface is particularly important for the tire characteristics such as fuel efficiency, safety and durability. Contribution is large. For this reason, many technical improvements of rubber compositions for tires have been studied and proposed and put to practical use.

[0003] For example, in terms of rubber performance of a tire tread, hysteresis loss is small for improving fuel economy.
It is required that the wet skid resistance is high in order to improve the steering stability, and the wear resistance is excellent in order to improve the durability. However, the relationship between low hysteresis loss and wet skid resistance is contradictory, and the relationship between abrasion resistance and wet skid resistance is also contradictory.It is important to improve the balance between these conflicting performances. At present, it is difficult to solve the problem with only one performance improvement. A typical method for improving a rubber composition for tires is to improve raw materials to be used.
Improvements have been made in the polymer structure of raw rubber represented by R, and in the structure and composition of reinforcing fillers such as carbon black and silica, vulcanizing agents, and plasticizers.

[0004] Among these, a technique which has attracted particular attention in recent years is a technique in which silica is used as a reinforcing filler instead of conventional carbon black. The typical technology is
For example, as shown in U.S. Pat. No. 5,227,425, by using silica as a reinforcing filler in SBR having a specific structure, and specifying the kneading conditions of the rubber composition, the fuel-saving performance of the tread rubber composition is improved. And a method for improving the balance between wet skid resistance performance. However, rubber compositions using silica as a reinforcing filler have some problems to be solved. For example, silica has lower affinity with rubber than conventional carbon black,
Dispersibility in rubber is not always good, and poor dispersibility tends to cause insufficient wear resistance and insufficient strength characteristics. In order to improve the dispersibility of silica, kneading is performed under specific temperature conditions using a silane coupling agent represented by bis- (triethoxysilylpropyl) -tetrasulfide, and the number of kneading is further increased to disperse the silica. Need to be improved.

Under these circumstances, the rubber ends are modified with various alkoxysilyl groups for the purpose of improving the dispersibility of silica in the rubber and reducing the amount of the silane coupling agent used. And a silica compound rubber composition using them are disclosed in
These are proposed in Japanese Patent Application Laid-Open Nos. 27908, 8-53513, 8-53576 and 9-225324. Further, a silica-blended composition using an epoxidized polymer has been proposed in JP-A-9-118785 and JP-A-9-241429.
In these methods, the modifying group obtained by modifying the rubber and the silane coupling agent compete with silica to react with each other, so that the balance between them cannot always be controlled properly.

In addition to attempts to improve the polymer used, attempts have been made to improve the method of kneading a filler mainly composed of rubber and silica.
No. 269305 and JP-A-11-263882 disclose that SBR, silica, and a silane coupling agent are kneaded in advance at a temperature of less than 130 ° C.
A method has been proposed in which a rubber composition having excellent balance of rolling performance, wet performance and abrasion resistance is provided by kneading at 80 ° C., but control in a low temperature range cannot increase productivity. There was a problem.

[0007]

In such a situation,
The present invention, in a silica blend, excellent processability,
It is another object of the present invention to provide a diene rubber composition having improved balance between low rolling resistance and wet skid resistance, strength characteristics, and the like.

[0008]

Means for Solving the Problems In order to solve the above-mentioned problems, the present inventors have conducted intensive studies on the molecular structure and modified structure of the diene-based polymer and on the production method, and have found that a modified group having an affinity for silica is obtained. Using a diene rubber-like polymer having, by performing a specific kneading method, to find that a rubber composition having excellent performance can be obtained,
The present invention has been reached.

That is, the present invention relates to (A-1) 100 parts by weight of a raw rubber containing a diene rubber-like polymer having a modifying group having an affinity for reinforcing silica, and (B-1) filling of reinforcing silica. 25 to 150 parts by weight of an agent, 0.1 to 15 parts by weight of (C) a silane coupling agent, and 1.0 to 20 parts by weight of a total of (D) a vulcanizing agent and a vulcanization accelerator. (1) In the first stage kneading, (A-1) the total amount of the diene rubber polymer having a modifying group having an affinity for the reinforcing silica is 7
0 to 100% by weight (B-1) 50 to 50% of the total amount of reinforcing silica
A mixture containing 0 to 10 parts by weight of 100% by weight of (C) silane coupling agent with respect to 100 parts by weight of reinforcing silica used at this stage is kneaded at least once at a kneading discharge temperature of 120 to 180 ° C., and then cooled. (2) Second-stage kneading with respect to the first composition obtained in (1), the remaining amount of the component (A-1), the remaining amount of the component (B-1),
(C) at least one of the remaining amounts of the components is added, and
After kneading at least once at a kneading discharge temperature of 180 ° C., the mixture is cooled to obtain a reinforcing silica-containing second composition. (3) As a third step, the second composition obtained in (2) is mixed with (D) ) The total amount of the components is added, the mixture is kneaded at a kneading discharge temperature of 120 ° C or lower, and then cooled to obtain a vulcanizable composition. (4) Reinforcing silica-containing rubber obtained by vulcanizing at a temperature of 130 to 200 ° C A method for producing a composition.

Further, the present invention provides (A-1) 100 parts by weight of a raw rubber containing a diene rubber-like polymer having a modifying group having an affinity for reinforcing silica, and (B-1) reinforcing silica. 25 to 150 parts by weight, (C) 0.1 to 15 parts by weight of a silane coupling agent, and (D) a total of 1.0 to 20 parts by weight of a vulcanizing agent and a vulcanization accelerator. (1) In the first stage kneading, (A-1) the total amount of the diene rubber-like polymer having a modifying group having an affinity for the reinforcing silica is 6%.
0 to 95% by weight, (B-1) 50 to 50% of the total amount of reinforcing silica
100% by weight of the (C) silane coupling agent is added in an amount of 0 to 10 parts by weight based on 100 parts by weight of the reinforcing silica used at this stage, kneading is started, and after reaching a temperature of 100 to 140 ° C, (A-1) ) Add the remaining amount of ingredients and continue kneading,
After kneading at least once at a kneading discharge temperature of 20 to 180 ° C., the mixture is cooled to obtain a first composition. (2) As a second-stage kneading, the first composition obtained in (1) is subjected to (B-1) At least one of the remaining amount of the component and the remaining amount of the component (C) is added, and the mixture is kneaded at least once at a kneading discharge temperature of 120 to 180 ° C., and then cooled to obtain a reinforcing silica-containing second composition. As a third step, a vulcanizable composition is obtained by adding the entire amount of the component (D) to the second composition obtained in (2), kneading at a kneading discharge temperature of 120 ° C. or lower, and then cooling. (4) A method for producing a reinforcing silica-containing rubber composition by a method of vulcanizing at a temperature of 130 to 200 ° C.

The present invention also relates to (A-1) a diene rubbery polymer 1 having a modifying group having an affinity for reinforcing silica.
A raw rubber comprising 5 to 99 parts by weight and 85 to 1 part by weight of (A-2) one or more rubbery polymers other than (A-1) is 100 parts by weight in total (B-1) reinforcing silica. 25-150
(C) 0.1 to 15 parts by weight of a silane coupling agent, and (D) a total of 1.0 to 2 parts of a vulcanizing agent and a vulcanization accelerator.
When obtaining a vulcanized reinforcing silica-containing rubber composition containing 0 parts by weight, (1) First-stage kneading (A-1) Diene rubber having a modifying group having an affinity for reinforcing silica 7 of the total amount of the polymer
0 to 100% by weight (A-2) The raw material rubber consisting of 30 to 0% by weight of the total amount of the rubbery polymer other than (A-1) has (B)
-1) 50 to 100% by weight of the total amount of reinforcing silica, (C)
A mixture containing 0 to 10 parts by weight of the silane coupling agent with respect to 100 parts by weight of the reinforcing silica used at this stage is kneaded at least once at a kneading discharge temperature of 120 to 180 ° C., and then cooled to obtain a first composition. (2) Second-stage kneading, with respect to the first composition obtained in (1), the remaining amount of the component (A-1), the remaining amount of the component (A-2),
At least one of the remaining amount of the component (B-1) and the remaining amount of the component (C) is added, and the mixture is kneaded at least once at a kneading discharge temperature of 120 to 180 ° C., and then cooled to obtain a reinforcing silica-containing second composition (3) As a third step, the entire amount of the component (D) is added to the second composition obtained in (2), and the mixture is kneaded at a kneading discharge temperature of 120 ° C. or lower, and then cooled, (4) A method for producing a reinforcing silica-containing rubber composition by a method of vulcanizing at a temperature of 130 to 200 ° C.

Further, the present invention relates to (A-1) 15 to 99 parts by weight of a diene rubber-like polymer having a modifying group having an affinity for reinforcing silica, and (A-2) one or more kinds of (A-2) -1)
Total of 1 to 85 to 1 part by weight of rubbery polymer other than component
25 parts by weight of (B-1) reinforcing silica containing
50 parts by weight, (C) 0.1 to 1 silane coupling agent
5 parts by weight, (D) a vulcanizing agent and a vulcanization accelerator in total of 1.0 to
In producing a rubber composition containing 20 parts by weight of vulcanized reinforcing silica-containing rubber composition, (1) first-stage kneading (A-1) a diene-based rubber having a modifying group having an affinity for reinforcing silica. The reinforcing silica of the component (B-1) is added in an amount of 50 to 100 based on the total amount of the polymer.
0 to 10 parts by weight of the silane coupling agent is added to 100 parts by weight of the reinforcing silica used at this stage, kneading is started, and after reaching a temperature of 100 to 140 ° C,
(A-2) The whole amount of the rubbery polymer as the component is added, and the kneading is continued. The mixture is kneaded at least once at a kneading discharge temperature of 120 to 180 ° C., and then cooled to obtain a first composition. (2) Second stage At least one of the remaining amount of the component (B-1) and the remaining amount of the component (C) is added to the first composition obtained in (1) as kneading, and the mixture is kneaded at a kneading discharge temperature of 120 to 180 ° C. After kneading at least once, the mixture is cooled to obtain a reinforcing silica-containing second composition. (3) As a third step, the total amount of the component (D) is added to the second composition obtained in (2). And kneading at a kneading discharge temperature of 120 ° C. or less, followed by cooling to obtain a vulcanizable rubber composition. (4) A method for producing a rubber composition obtained by a method of vulcanizing at a temperature of 130 to 200 ° C. .

Hereinafter, the present invention will be described in detail. The method for producing a rubber composition of the present invention includes a raw rubber containing a diene rubber-like polymer having a modifying group having affinity for silica (hereinafter, may be simply referred to as a modifying group), reinforcing silica,
Using a silane coupling agent as a main component, kneading is performed in a specific method and under specific conditions, and then vulcanized. The diene rubber-like polymer uses a conjugated diene represented by butadiene or isoprene as a monomer, and is a homopolymer thereof or a copolymer with a vinyl aromatic compound such as styrene. It is obtained by anionic polymerization using an organic alkali metal represented by alkyllithium as a catalyst, or obtained by radical polymerization, and contains a specific modifying group. As the modifying group having affinity for silica contained in the diene rubbery polymer, various modifying groups are selected,
As examples thereof, polar modifying groups such as an alkylamino group, an amide group, a glycidyl group and a silanol group are effective. Examples of a method for obtaining a rubber-like polymer containing such a polar modifying group include, in an inert solvent, a conjugated diene-based rubber-like polymer having an active terminal obtained by anionic polymerization and imparting a polar modifying group. It is obtained by reacting a possible polyfunctional compound. One example of a polyfunctional compound to which a polar modifying group can be imparted is a polyfunctional compound having two or more epoxy groups in a molecule, and two or more epoxy groups and one or more nitrogen-containing groups in a molecule. Is preferable, and examples thereof include compounds represented by the following general formula (1).

[0014]

Embedded image

However, R ¹ and R ^{2 each} have 1 to 10 carbon atoms.
And a hydrocarbon group having 1 to 10 carbon atoms having a tertiary amine, R ³ and R ⁴
Is hydrogen, a hydrocarbon group or ether having 1 to 20 carbon atoms and / or a hydrocarbon group having 1 to 20 carbon atoms having a tertiary amine, and R ⁵ is a hydrocarbon group or ether having 1 to 20 carbon atoms and a tertiary amine. It is a hydrocarbon group having 1 to 20 carbon atoms having at least one group among amine, epoxy, carbonyl and halogen, and n is 1 to 6. Examples of the specific compound include polyglycidyl ethers of polyhydric alcohols such as ethylene glycol diglycidyl ether,
Polyepoxy compounds such as 4-diglycidylbenzene and polyepoxidized liquid polybutadiene; tertiary amines containing epoxy groups such as 4,4'-diglycidyl-diphenylmethylamine and 4,4'-diglycidyl-dibenzylmethylamine; diglycidyl Examples thereof include diglycidylamino compounds such as aniline, diglycidyl orthotoluidine, tetraglycidyl metaxylenediamine, diglycidylaminomethylcyclohexane, and tetraglycidyl-1,3-bisaminomethylcyclohexane.

These polyfunctional compounds having two or more epoxy groups in the molecule are reacted at a ratio of epoxy group / active terminal of the rubbery polymer of 0.3 equivalent to 10 equivalent,
By increasing the amount of the polyfunctional compound, it becomes possible to leave the epoxy group as a modifying group. Examples of the polyfunctional compound to which a polar modifying group can be added include a compound having a functional group represented by the following general formula (2),
Typical examples thereof include an N-alkyl cyclic lactam compound, an N-alkyl cyclic urea compound and an N-alkyl benzophenone compound.
N-methylpyrrolidone, dimethylimidazoline, N, N
', There is dimethylbenzophenone.

[0017]

Embedded image Here, R ⁶ is a hydrocarbon group having 1 to 20 carbon atoms or a hydrocarbon group having 1 to 20 carbon atoms having at least one group among ether, tertiary amine, epoxy, carbonyl, and halogen.

Further, examples of the polyfunctional compound to which a polar modifying group can be imparted include a polyfunctional compound containing two or more alkoxy groups in the molecule. In particular, in addition to the two or more alkoxy groups in the molecule, Further, those containing an alkylamino group or an epoxy group in the molecule are more preferable. Specific examples of these include tetramethoxysilane, glycidoxypropyltrimethoxysilane, and the like. In addition to the above-described reaction with the active terminal of anionic polymerization, a conjugated diene monomer, a vinyl aromatic monomer, and a specific vinyl monomer containing a modifying group having an affinity for silica by radical polymerization. And a method in which a compound having a modifying group having an affinity for silica is added to a double bond such as polybutadiene, styrene-butadiene copolymer, or polyisoprene obtained by pre-polymerization. The amount of the modifying group having an affinity for silica in the diene-based rubbery polymer used in the present invention is preferably 0.05 mmol or more, more preferably 0.2 mmol or more, per 100 parts by weight of the polymer.

The molecular weight distribution Mw / Mn of the diene rubbery polymer (A-1) having a modifying group having an affinity for silica used in the present invention is 1.02 to 5.0, preferably 1.05 to 5.0.
４4.0. The molecular weight distribution uses GPC,
It is determined by a method of measuring from the molecular weight of standard polystyrene. If the molecular weight distribution is less than 1.02, processability is poor,
Moreover, it is difficult to manufacture industrially. When it exceeds 5.0, the mechanical strength of the obtained rubber composition is inferior. A polymer having a molecular weight distribution of 2.2 or more has advantages such as excellent workability during kneading, a small torque during processing, and a short kneading time. On the other hand, the molecular weight distribution is 2.
When it is less than 2, the workability is generally poor, and particularly in the case of silica blending, the torque at the time of processing becomes large. Therefore, conventionally, it was necessary to use a large amount of carbon black in combination. In the case of the present invention, the processability is excellent even when the compounding amount of carbon black is small because the affinity for silica is particularly increased, and furthermore, the fuel economy and wet skid resistance of the obtained rubber composition are improved. The balance is excellent and the strength properties are more excellent.

The weight average molecular weight of the diene rubbery polymer (A-1) having a modifying group having an affinity for silica of the present invention must be 100,000 to 2,000,000. The weight average molecular weight is determined by using GPC and measuring from the molecular weight of standard polystyrene. When the weight average molecular weight is less than 100,000, the strength and abrasion resistance of the obtained rubber composition decrease, and 2,000,000
If the ratio exceeds the above range, the processability will be extremely reduced and it will be difficult to obtain a rubber composition. Mooney viscosity of the diene rubber-like polymer having a modifying group having an affinity for silica of the present invention,
Preferably it is in the range of 20 to 200. This Mooney viscosity is measured using the Mooney viscometer specified in the standard.
Mooney viscosity measured at 100 ° C (ML1 + 4 (100 ° C))
It is. When the Mooney viscosity is less than 20, the strength and abrasion resistance of the obtained rubber composition are reduced, and when it exceeds 200, the processing performance is extremely reduced and it becomes difficult to obtain the rubber composition. The Mooney viscosity is more preferably in the range of 25 to 180. The diene-based rubber-like polymer (A-1) having a modifying group having an affinity for silica of the present invention is prepared by using an ordinary rubber-extending oil for rubber 10 to make the processing easier.
It is also possible to practically use as an oil-extended rubber in which 10 to 60 parts by weight is added per 0 part by weight.

The glass transition temperature of the diene rubbery polymer (A-1) having a modifying group having an affinity for silica of the present invention is -100 because the rubber composition finally obtained shows rubber elasticity. The range of to 0 ° C is preferred. Furthermore, -95 ~
A range of −10 ° C. is more preferred. The glass transition temperature is controlled by the composition of the constituent conjugated diene and styrene, and when the conjugated diene is butadiene or isoprene, the microstructure (1,4-bond and 1,2-bond) in the polymer chain is controlled.
And 3,4-bond). When the diene-based rubbery polymer having a modifying group having an affinity for the silica of the present invention is polybutadiene, the 1,2-bond amount of the microbonds of butadiene is preferably 10 to 80%, and the affinity for the silica of the present invention is high. When the rubbery copolymer having a functional modifying group is a styrene-butadiene random copolymer, the styrene content is 5 to 60%, preferably 5 to 50%, more preferably 5 to 45%. The block amount is less than 4%, preferably 1% or less. The 1,2-bond amount of the micro bond of the butadiene portion is preferably in the range of 10 to 70%. In the case of a styrene-butadiene block copolymer having a styrene block in the molecule, the styrene content is 5 to 60%, preferably 5 to 50%, more preferably 5 to 45%, and the styrene block is 4 to 50%.
It is 30%, preferably 4 to 20%. The 1,2-bond amount of the micro bond in the butadiene portion is preferably in the range of 10 to 70%.

The rubbery polymer (A-1) of the present invention is not limited to one kind but may be, for example, two or more kinds of rubbery polymers. In that case, in the case of polybutadiene and a styrene-butadiene copolymer rubber, a combination of styrene-butadiene copolymer rubbers having different molecular weights / molecular weight distributions and different glass transition temperatures may be used. In the present invention, it is possible to use only the component (A-1) as the raw rubber, and further, 15 to 99% by weight of the component (A-1) and (A-1) as the component (A-2).
It is also possible to use a raw rubber consisting of 1 to 85% by weight of a rubbery polymer other than the components. As the (A-2 component), one or more of synthetic rubber and natural rubber may be used as necessary. When the (A-2 component) is specifically shown, (A-
1) One or more rubbers selected from butadiene rubber, styrene-butadiene rubber, styrene-isoprene-butadiene rubber, synthetic polyisoprene rubber, butyl rubber, and natural rubber other than the components. The composition is optimized for physical properties and processability according to the intended use of the rubber composition.

As the reinforcing silica of the component (B-1) of the present invention, any of wet-process silica, dry-process silica, and synthetic silicate-based silica can be used. Silica having a small particle diameter has a high reinforcing effect and a high effect of improving grip performance, and a small particle diameter and high aggregation type is preferable. In the reinforcing silica of the present invention, 25 to 150 parts by weight per 100 parts by weight of the raw rubber is used as a filler having a reinforcing effect. If it is less than 25 parts by weight, strength and other physical properties are inferior,
If it exceeds 150 parts by weight, the rubber composition becomes too hard, the strength is rather reduced, and the rubber performance is reduced. The amount of the reinforcing silica as the component (B) is preferably 30 to 100 parts by weight.

Next, the rubbery polymer composition of the present invention contains, as the component (C), an organic silane coupling agent of 0.1 to 0.1%.
Use 15 parts by weight. The organic silane coupling agent is preferably (B-) in order to make the coupling action (interaction) between the reinforcing silica filler and the raw rubber tight.
1) 0.1-20% by weight of reinforcing silica is added.
When the amount of the organic silane coupling agent exceeds 15 parts by weight, the reinforcing property is impaired. The organic silane coupling agent has a double bond of a polymer and a group having an affinity or a bonding property on a silica surface in a molecule. Examples include bis- [3- (triethoxysilyl) -propyl] -tetrasulfide, bis- [3- (triethoxysilyl) -propyl] -disulfide, bis- [2-
(Triethoxysilyl) -ethyl] -tetrasulfide, 3-mercaptopropyl-trimethoxysilane, 3
-Triethoxysilylpropyl-N, N-dimethylthiocarbamoyltetrasulfide, 3-triethoxysilylpropylbenzothiazoletetrasulfide and the like.

In the rubber composition of the present invention, it is possible to use the reinforcing carbon black of the component (B-2) as long as the performance of the reinforcing silica is not impaired. As the reinforcing carbon black, FT, SRF,
Each class of carbon black such as FEF, HAF, ISAF, SAF, etc. can be used, and the nitrogen adsorption specific surface area is 50 mg.
/ G or more, and carbon black having a DBP oil absorption of 80 ml / 100 g is preferable. The amount of the reinforcing carbon black is 0.1 to 100 parts by weight per 100 parts by weight of the raw rubber, and (B-1 component) reinforcing silica and (B-2 component)
The total amount of carbon black is preferably 30 to 150 parts by weight. The vulcanizing agent and vulcanization accelerator of the (D component) of the present invention are used in an amount of 1 to 20 parts by weight per 100 parts by weight of the rubbery polymer. As a typical vulcanizing agent, sulfur is used, and in addition, a sulfur-containing compound, a peroxide and the like are used. Sulfenamide-based, guanidine-based, thiuram-based, and the like are used as vulcanizing accelerators as needed.

In the composition of the present invention, a rubber extending oil is used if necessary. As extender oils for rubber, in addition to conventionally used aromatic, naphthenic and paraffinic extender oils, rubbers that are low in polynuclear aromatic components such as MES, T-DAE, T-RAE and are environmentally friendly Extender oils can also be used. In the present invention, when a rubber extender oil is used, 1 to 100 parts by weight is used per 100 parts by weight of the raw rubber. The amount of the rubber extender oil is increased or decreased according to the amounts of the reinforcing silica filler and the reinforcing carbon black described below, and is used to adjust the elastic modulus of the compound after vulcanization. If the amount of the rubber extender oil exceeds 100 parts by weight, the hysteresis loss performance and abrasion resistance of the obtained rubber composition are undesirably deteriorated. The amount of extender oil for rubber is 1-60
A range of parts by weight is preferred. Further, the present invention provides, as necessary, other additives such as zinc white, stearic acid, a vulcanization aid, an antioxidant, and a processing aid in an amount according to the purpose, for example, 0.1 to 20 parts by weight. Used in.

[0027] The present invention relates to the component (A-1) or (A-
Component 1), component (A-2) and component (B-1), and if necessary, component (B-2), component (C), and other additives, using a well-known closed kneader such as an internal mixer. However, a process of cooling after kneading by a specific method is required three times or more. This is necessary for maximizing the performance of the rubber (A-1) having a modifying group having an affinity for silica. In the conventional kneading method in which the components of raw rubber, reinforcing silica, and silane coupling agent are collectively charged, effective results cannot be obtained even if the kneading and cooling steps are repeated. .

The method of the present invention when (A-1) is used as a raw material rubber is as follows: (1-1) As the first stage kneading, (A-1) a diene having a modifying group having an affinity for reinforcing silica. 70 to 100% by weight of the total amount of the rubber-based polymer (B-1) 5 of the total amount of the reinforcing silica
0 to 100% by weight of the (C) silane coupling agent is used in an amount of 0 to 1 based on 100 parts by weight of the reinforcing silica used at this stage.
The mixture containing 0 parts by weight was kneaded at least once at a kneading discharge temperature of 120 to 180 ° C., and then cooled to obtain a first composition. (1-2) Second-stage kneading obtained in (1-1) At least one of the remaining amount of the component (A-1), the remaining amount of the component (B-1), and the remaining amount of the component (C) is added to one composition,
After kneading at least once at a kneading discharge temperature of 120 to 180 ° C., the mixture is cooled to obtain a reinforcing silica-containing second composition. (1-3) As a third step, the second composition obtained in (1-2) The whole amount of the component (D) is added to the mixture, and the mixture is kneaded at a kneading discharge temperature of 120 ° C. or less and then cooled to obtain a vulcanizable composition. How to

Another method is as follows: (2-1) as the first-stage kneading, (A-1) 60 to 95% by weight of the total amount of the diene rubbery polymer having a modifying group having an affinity for the reinforcing silica, (B-1) 5 of the total amount of reinforcing silica
0 to 100% by weight of the (C) silane coupling agent is used in an amount of 0 to 1 based on 100 parts by weight of the reinforcing silica used at this stage.
0 parts by weight are added to start kneading, and after reaching a temperature of 100 to 140 ° C., the remaining amount of the component (A-1) is added to continue kneading, and kneading is performed at least once at a kneading discharge temperature of 120 to 180 ° C. After cooling, the first composition was obtained. (2-2) The second stage kneading was performed with respect to the first composition obtained in (2-1) with respect to the remaining amount of the component (B-1) and the component (C). And kneading at least once at a kneading discharge temperature of 120 to 180 ° C., followed by cooling to obtain a reinforcing silica-containing second composition. (2-3) As a third step, To the second composition obtained in 2-2), the entire amount of the component (D) is added, and the mixture is kneaded at a kneading discharge temperature of 120 ° C. or lower and then cooled to obtain a vulcanizable composition. 4) Vulcanization at a temperature of 130 to 200 ° C.

In the first-stage kneading in (1-1) and (2-1), the diene rubber-like polymer having a modifying group and the reinforcing silica are effectively kneaded, and the reinforcing silica and the reinforcing silica are mixed. The chemical bond of the diene rubber-like polymer or the interaction between the silica and the diene rubber-like polymer is strengthened to improve the fuel-saving performance,
Performed to increase the strength of the composition. The temperature at this stage is preferably in the range of 130 to 170C. The second-stage kneading in (1-2) and (2-2) is a step of adding and kneading the remaining components to improve the dispersibility of each component, improve the moldability, and improve the reinforcing silica. This is a step of improving the abrasion resistance by improving the dispersion. The temperature at this stage is 140 ~
A range of 170 ° C. is preferred. In the kneading up to the second stage, the amount of bound rubber after kneading (the ratio of the raw rubber component bonded to the reinforcing filler) is preferably 30 to 70% by weight.

In addition, rubber oil, carbon black, vulcanization aids such as zinc oxide and stearic acid, antioxidants, etc., which are added as required other than the raw rubber, reinforcing silica and silane coupling agent. It is preferable to add an antioxidant which may hinder the reaction between the diene rubber-like polymer containing a modifying group and the reinforcing silica in the latter half of the kneading so as to reduce the adverse effect. The third-stage kneading of (1-3) and (2-3) is a step of adding a vulcanization system composed of sulfur and a vulcanization accelerator, and (1-4) and (2-)
4) is a step of vulcanizing the composition, and in these steps, a conventional method can be applied.

On the other hand, (A-1) and (A-
In the case where the component (A) is used, prior to the reaction between the component (A-2) and the reinforcing silica, a diene polymer having a modifying group having an affinity for the silica of the component (A-1) is reinforced. It is necessary to surely carry out the reaction with the silica. The method is as follows: (3-1) First stage kneading (A-1) 70 to 100% by weight of the total amount of the diene rubber-like polymer having a modifying group having an affinity for reinforcing silica (A-2) (B-1) 50 to 100% by weight of the total amount of reinforcing silica, based on 30 to 0% by weight of the total amount of the rubbery polymer other than (A-1).
(C) A mixture containing 0 to 10 parts by weight, based on 100 parts by weight of the reinforcing silica used at this stage, of the silane coupling agent is kneaded at least once at a kneading discharge temperature of 120 to 180 ° C., and then cooled, (3-2) Residual amount of component (A-1) and residual amount of component (A-2) with respect to the first composition obtained in (3-1) as second stage kneading. , At least one of the remaining amount of the component (B-1) and the remaining amount of the component (C) is added, and the mixture is kneaded at least once at a kneading discharge temperature of 120 to 180 ° C., and then cooled to obtain a reinforcing silica-containing second mixture. (3-3) As a third step, add the entire amount of the component (D) to the second composition obtained in (3-2), and knead the mixture at a kneading discharge temperature of 120 ° C or lower. (3-4) A method of vulcanizing at a temperature of 130 to 200 ° C.

Further, as another method of the present invention, (4-1) as the first-stage kneading, (A-1) the total amount of the diene rubber-like polymer having a modifying group having an affinity for the reinforcing silica, B-1) The reinforcing silica of the component is used in a total amount of 50 to 1
After adding 0 to 10 parts by weight of 100% by weight of the silane coupling agent (C) to 100 parts by weight of the reinforcing silica used at this stage, kneading was started, and after reaching a temperature of 100 to 140 ° C, (A- 2) The whole amount of the rubbery polymer as the component is added and the kneading is continued, and the mixture is kneaded at least once at a kneading discharge temperature of 120 to 180 ° C and then cooled to obtain a first composition. (4-2) Second-stage kneading To the first composition obtained in (4-1), at least one of the remaining amount of the component (B-1) and the remaining amount of the component (C) is added, and a kneading discharge temperature of 120 to 180 ° C. After kneading at least once, the mixture is cooled to obtain a reinforcing silica-containing second composition. (4-3) As a third step, the component (D) is added to the second composition obtained in (4-2). And kneading at a kneading discharge temperature of 120 ° C. or lower, followed by cooling to obtain a vulcanizable rubber composition. (4-4) A method of vulcanizing at a temperature of 130 to 200 ° C..

In the first stage kneading in (3-1) and (4-1), the diene rubber-like polymer having a modifying group and the reinforcing silica are effectively kneaded, and the reinforcing silica and the reinforcing silica are mixed. The chemical bond of the diene rubber-like polymer or the interaction between the silica and the diene rubber-like polymer is strengthened to improve the fuel-saving performance,
Performed to increase the strength of the composition. The temperature at this stage is preferably in the range of 130 to 170C. The second-stage kneading in (3-2) and (4-2) is a step of adding and kneading the remaining components to improve the dispersibility of each component, improve the moldability, and improve the reinforcing silica. This is a step of improving the abrasion resistance by improving the dispersion. The temperature at this stage is 140 ~
A range of 170 ° C. is preferred. In the kneading up to the second stage, the amount of bound rubber after kneading (the ratio of the raw rubber component bonded to the reinforcing filler) is preferably 30 to 70% by weight. In addition, in addition to the raw rubber, reinforcing silica and silane coupling agent, rubber extender oil, carbon black, vulcanization aids such as zinc oxide and stearic acid, antioxidants, etc. It is preferable to add an antioxidant or the like which may hinder the reaction between the diene rubber-like polymer containing the compound and the reinforcing silica in the latter half of the kneading so as to reduce the adverse effect.

The third-stage kneading of (3-3) and (4-3) is a step of adding a vulcanization system comprising sulfur and a vulcanization accelerator, and (3-4) and (3-4) Is a step of vulcanizing the composition, and in these steps, a conventional method can be applied. In the above kneading process, kneading using a known kneader such as an internal mixer or a mixing roll is important to control the kneading discharge temperature, and the shape and rotation speed of the rotor and the like of the mixer, mixing It is adjusted by the filling amount of the rubber composition in the machine. In the present invention, the vulcanization is performed at a temperature of 130 to 200 ° C, preferably 140 to 1.
It is carried out at a temperature of 80 ° C. and exhibits its performance in the state of the obtained diene polymer rubber vulcanizate. The rubbery polymer of the present invention, in the form of a diene-based polymer rubber vulcanizate, is suitably used in a tire tread compound which is representative of high-performance tires and all-season tires. It can also be applied to applications, anti-vibration rubber, belts, industrial supplies, footwear, etc., taking advantage of its features.

Hereinafter, the present invention will be described specifically with reference to Examples and Comparative Examples, but these do not limit the scope of the present invention.

Reference Example 1 Production method of SBR-1: An internal volume of 10 liters, an inlet at the bottom and an outlet at the head, two autoclaves equipped with a stirrer and a jacket were connected in series as reactors, and 16 After mixing .38 g / min, styrene at 8.82 g / min and n-hexane at 132.3 g / min, the mixed solution was passed through a dehydration column filled with activated alumina to remove n. -Butyllithium was mixed at a rate of 0.0046 g / min in a static mixer, and then continuously supplied from the bottom of the first reactor using a metering pump. Further, 2,2-bis (2 -Oxolanyl) propane in 0.02
N-Butyl lithium as a polymerization initiator was supplied directly to the reactor at a rate of 2 g / min at a rate of 0.0060 g / min, and the temperature inside the reactor was maintained at 83 ° C. The polymer solution was continuously withdrawn from the reactor head and supplied to the second reactor. After the state of the first reactor was stabilized, the Mooney viscosity of the resulting polymer before the modification reaction was 80 as measured at 100 ° C.
The temperature of the second reactor was kept at 80 ° C., and tetraglycidyl-1,3-bisaminomethylcyclohexane was added to 0.02 ° C.
It was added from the bottom of the reactor at a rate of 309 g / min (equivalent ratio to active lithium = 4) to cause a modification reaction. An antioxidant was continuously added to the polymer solution to terminate the modification reaction, and then the solvent was removed to obtain a styrene-butadiene copolymer having a desired modification component. The Mooney viscosity of the polymer after this modification was 140 as measured at 120 ° C. Further, an aromatic oil (X-140 manufactured by Japan Energy Co., Ltd.) was added to the polymer solution at 37.5 parts by weight per 100 parts by weight of the polymer to obtain an oil-extended rubber (Sample A).

As a result of analyzing Sample A, the amount of bound styrene was 35%, the amount of bound butadiene was 65%, and one of the butadiene moieties calculated from the measurement results using an infrared spectrophotometer according to the Hampton method was used. , 2-bond amount is 33 mol%, Mooney viscosity after oil extension (ML1 + 4, 100 ° C.) is 70,
GPC with glass transition temperature of -36 ° C and THF as solvent
The molecular weight distribution by measurement (detector: RI) was such that the weight average molecular weight (Mw) in terms of polystyrene was 713,000, the number average molecular weight (Mn) was 366,000, and the molecular weight distribution (Mw / M).
n) was 1.95, and the shape of the GPC curve was monomodal. GPC using a silica-based adsorption column
The modification rate determined from the curve was 75% by weight.

[0038]

REFERENCE EXAMPLE 2 SBR production method-2: 565 g of butadiene from which impurities were removed, 350 g of styrene, and 350 g of cyclohexane were used as reactors, using an autoclave having an internal volume of 10 liters and having a stirrer and a jacket and capable of controlling temperature, as a reactor. 5,500 g and 0.40 g of 2,2-bis (2-oxolanyl) propane as a polar substance were put into the reactor, and the temperature inside the reactor was maintained at 30 ° C. A cyclohexane solution containing 0.85 g of n-butyllithium as a polymerization initiator was supplied to the reactor. After the start of the reaction, the sound in the reactor gradually increased due to the heat generated by the polymerization. 75 g of butadiene was added to the mixture over a period of 7 to 12 minutes after the addition of the polymerization initiator.
g / min. The final reactor temperature is 73 ° C
Reached. After the completion of the polymerization reaction, a part of the polymer solution was collected. The Mooney viscosity of the polymer before the modification reaction measured after removing the solvent was 8 at 100 ° C.

As a modifier, 2.42 tetraglycidyl-1,3-bisaminomethylcyclohexane was added to the reactor.
g and maintained at 75 ° C. for 5 minutes to carry out a denaturation reaction. After adding an antioxidant to the polymer solution, the solvent was removed to obtain a styrene-butadiene copolymer (Sample B) having a desired modified component. The Mooney viscosity of the polymer after modification was 69 as measured at 100 ° C. Analysis of Sample B showed that the amount of bound styrene was 35% and the amount of bound butadiene was 65%. The 1,2-bond amount in the microstructure of the butadiene portion calculated from the measurement results using an infrared spectrophotometer according to the Hampton method is 40 mol%, and the molecular weight distribution in terms of polystyrene by GPC measurement is: , The weight average molecular weight (Mw) is 446,000, the number average molecular weight (Mn) is 2880, the molecular weight distribution (Mw / Mn) is 1.55, the glass transition temperature is -32 ° C, and silica-based adsorption. The denaturation rate determined by GPC using a column was 83% by weight. Further, in the same manner as the sample B was obtained,
Sample C having a modifying group having an affinity for silica shown in Table 1
Sample D and Sample E having no affinity for silica were prepared.

[0040]

[Reference Example 3] Production method 3 of SBR: an internal volume of 10 liters, a stirrer and a jacketed autoclave capable of temperature control were used as a reactor, and 550 g of butadiene, 450 g of styrene, and cyclohexane of impurities were removed. 5,500 g and 0.40 g of 2,2-bis (2-oxolanyl) propane as a polar substance were put into the reactor, and the temperature inside the reactor was maintained at 30 ° C. 6.2 ml of a cyclohexane solution containing 0.95 g of n-butyllithium as a polymerization initiator was supplied to the reactor. After the start of the reaction, the sound in the reactor gradually increased due to the heat generated by the polymerization. The final reactor temperature reached 81 ° C. After the completion of the polymerization reaction, a part of the polymer solution was collected. The Mooney viscosity of the polymer before the modification reaction measured after removing the solvent was 38 at 100 ° C.
2.88 g of tetraglycidyl-1,3-bisaminomethylcyclohexane was added to the reactor as a modifier,
The denaturation reaction was carried out at 8 ° C. for 5 minutes. After adding an antioxidant to this polymer solution, the solvent was removed to obtain a styrene-butadiene block copolymer (Sample F) having a desired modified component. A sample G which was similarly polymerized and unmodified and had no affinity for silica was prepared. Sample F had a styrene block amount of 13%, and sample G had a styrene block amount of 13.5.
%Met. In addition, commercially available styrene butadiene rubbers, butadiene rubbers, and natural rubbers of samples RA to RD shown in Table 2 were also used as samples.

The analysis values of the above samples are shown in Tables 1 and 2.
The analysis of the sample was performed by the following method. 1) Amount of bound styrene A sample was prepared as a chloroform solution, and the amount of bound styrene [S] was determined by the absorption of UV at 254 nm by the phenyl group of styrene.
(Wt%) was measured. 2) Amount of styrene block The sample was dissolved in chloroform, decomposed with osmium tetroxide, reprecipitated in methanol, filtered through a glass filter, dried and determined from its weight. 3) Microstructure of butadiene portion The sample was prepared as a carbon disulfide solution, and the infrared spectrum was measured in the range of 600 to 1000 cm ^-1 using a solution cell, and the microstructure of the butadiene portion was calculated from the predetermined absorbance according to the Hampton formula. I asked. 4) Glass transition temperature Measured at a heating rate of 10 ° C./min using DSC. The extrapolation start temperature (On set point) was defined as Tg.

5) Mooney viscosity, JIS K 6300
The viscosity was measured after 4 minutes at 100 ° C and 1 minute preheating. 6) Molecular weight and molecular weight distribution A chromatogram was measured using GPC using three columns connected with a polystyrene-based gel as a filler, and the molecular weight and molecular weight distribution were calculated using a calibration curve using standard polystyrene. 7) Modification rate By applying the property of adsorbing the modified polymer to a GPC column using silica gel as a filler, the polystyrene gel (5) described above for sample and sample solution containing low molecular weight internal standard polystyrene was applied. Made by Shodex) GP
C and silica-based column GPC (Zorba manufactured by DuPont)
Both chromatograms of x) were measured, and the amount of adsorption on the silica column was measured from the difference between them to determine the denaturation rate (% by weight).

[0043]

EXAMPLES Using the samples shown in Tables 1 and 2 as raw rubbers and using the formulations shown in Table 3, rubber compounds were obtained by the following kneading method.

[0044]

[Table 1]

[0045]

[Table 2]

[0046]

[Table 3]

[Kneading method] A closed kneader equipped with a temperature control device using circulating water from the outside (capacity: 1.7 liter)
It was used. The final filling rate was set to 65%, and the rotor rotation speed was 66/77 rpm. The kneading procedure is shown in each table of Examples and Comparative Examples. The “input time (minute / second)” in the kneading method shown in each of Tables 4 to 8 is the elapsed time from the start of kneading in each step (“0′00”) to the input time of each compounding material. And "total kneading time (min)" represents the total kneading time in each step. In each kneading stage, the temperature of the closed mixer was controlled to obtain a rubber composition having a predetermined discharge temperature. The next kneading stage proceeded after the formulation had cooled to room temperature.

This was molded and vulcanized with a vulcanizing press at 160 ° C. for a predetermined period of time, and the properties of the following tire properties were measured. 1) Bound rubber amount: After completion of the second-stage kneading, 0.2 g of the sampled composition was cut into approximately 1 mm squares, placed in a Harris basket (made of 100 mesh wire mesh), and measured for weight. After being immersed in toluene for 24 hours, the weight was measured, and the amount of rubber bonded to the filler was calculated from the amount of undissolved components to obtain the bound rubber amount. 2) Formula Mooney viscosity: Using Mooney viscometer, J
According to IS K 6300, preheating at 130 ° C. for 1 minute, 2
Measure viscosity 4 minutes after rotation. If the Mooney viscosity exceeds 80, workability is poor. If the Mooney viscosity is 30 or less, the adhesion becomes large and it becomes difficult to process. 3) 300% modulus and tensile strength: JIS K6
251 measured by the tensile test method. 4) Fuel economy characteristics: Tested with Tan δ at 50 ° C. Measured at 50 Hz with a frequency of 10 Hz and a strain of 3% using an ARES viscoelasticity tester manufactured by Rheometrics Co., Ltd. by the torsion method.
The smaller the number, the better the fuel economy performance. 5) Wet skid resistance performance: Tan δ at 0 ° C.
Test with. Rheometrics Ales viscoelasticity tester, torsion method, frequency 10Hz, strain 3%, 0
Measured in ° C. The higher the number, the better the wet skid resistance performance.

[0049]

Examples 1-1 to 1-8,

Comparative Examples 1-1 to 1-3 As the raw rubber, a sample A, which is an SBR having a modifying group having an affinity for silica, and a commercially available emulsion-polymerized SBR for comparison were used. Using M1 and M2, rubber compositions were produced by the kneading methods shown in Tables 4-1 to 4-3 and vulcanized. The results of measuring the performance as a tire tread rubber are shown in Table 4-
It is shown in FIG. As shown in Table 4-4, the rubber compositions of Examples 1-1 to 1-7 produced by the specific kneading method of the present invention using Sample A having a modifying group having an affinity for silica are as follows: As compared with the rubber composition of Comparative Example 1-1 obtained by a usual method using a rubber having the same modifying group, the amount of the bound rubber (the ratio of the raw rubber component bonded to the reinforcing filler) was reduced. The interaction between silica and rubber increases, the processability represented by the Mooney viscosity of the compound is good, and the tire performance such as tensile strength, fuel economy and wet skid resistance is excellent. On the other hand, sample RA (emulsion polymerization SBR) having no modifying group of Comparative Example 1-3
In the case of using the sample RA (Emulsion Polymerization S) which does not have a modifying group, the tire performance of tensile strength, fuel economy and wet skid resistance can be similarly obtained by the kneading method of the present invention.
No improvement was obtained as compared with the composition produced by the ordinary kneading method of Comparative Example 1-2 using BR).

[0050]

[Table 4]

[0051]

[Table 5]

[0052]

[Table 6]

[0053]

[Table 7]

[0054]

Examples 2-1 to 2-3],

Comparative Examples 2-1 to 2-5 As raw rubbers, Samples B and C having modifying groups having an affinity for silica shown in Table 1 were prepared.
Using Sample D, Sample E having no affinity for silica for comparison, using N1 shown in Table 3 for formulation, Table 5-1 to Table 5-1
Rubber compositions were produced by the kneading methods shown in Table 5-2. The results of measuring the performance as a rubber for a tire tread are shown in Table 5-3. As shown in Table 5-3, Example 2-1 to Example 2- produced by the specific kneading method of the present invention using Sample B, Sample C, and Sample D having a modifying group having an affinity for silica. Comparative Examples 2-1 to 3 obtained by a usual method using the rubber having the same modifying group
Compared to the rubber composition of Comparative Example 2-3, each had a larger amount of bound rubber, increased interaction between silica and rubber, and had good workability represented by the blend Mooney viscosity, and a high tensile strength. The tires are excellent in fuel economy and wet skid resistance. On the other hand, Comparative Example 2-5
In the case of using the sample E (modified with tin coupling) having no modified group, the tire performances of the tensile strength, the fuel economy and the wet skid resistance can be similarly changed by the kneading method of the present invention. The improvement effect is small compared to the composition produced by the ordinary kneading method of Comparative Example 2-4 using Sample E (tin-coupling modified) having no.

[0055]

[Table 8]

[0056]

[Table 9]

[0057]

[Table 10]

[0058]

Example 2-4,

Comparative Examples 2-6 and 2-7 Sample F of a styrene-butadiene block copolymer having a modifying group having an affinity for silica as shown in Table 1 as a raw rubber, and having no affinity for silica for comparison Using the sample G of the styrene-butadiene block copolymer, the compounding was carried out using N1 shown in Table 3 and a kneading method shown in Table 6-1 was used to produce a rubber composition.
The results of measuring the performance as a rubber are shown in Table 6-2. As shown in Table 6-2, the rubber composition of Example 2-4 produced by the specific kneading method of the present invention using the sample F having a modifying group having an affinity for silica has the same modifying group. Comparative Example 2-6 obtained by an ordinary method using Sample F having
Compared to the rubber composition of any of the above, the amount of bound rubber is large, the interaction between silica and rubber is large, and the tire performance such as tensile strength, fuel economy, wet skid resistance, etc. is excellent. Excellent compression set and heat resistance. On the other hand, the composition using the sample G having no modifying group of Comparative Example 2-7 was also obtained by the kneading method of the present invention.
All performances are inferior to Examples 2-4.

[0059]

[Table 11]

[0060]

[Table 12]

[0061]

Examples 3-1 to 3-7],

Comparative Examples 3-1 to 3-3 Samples A and B having modifying groups having affinity for silica shown in Table 1 as raw rubbers
The composition of the sample RB with the butadiene rubber was blended using P1 and P2 shown in Table 3;
The rubber composition was manufactured by the kneading method shown in -2. Table 7 shows the results of measuring the performance as a tire tread rubber.
-3. As shown in Table 7-3, the rubber compositions of Examples 3-1 to 3-7 produced by the specific kneading method of the present invention were obtained by a usual method using a rubber having the same modifying group. Compared with the rubber compositions of Comparative Examples 3-1 to 3-3, all have a large amount of bound rubber and an increased interaction between silica and rubber, and the processability represented by the blend Mooney viscosity is low. The tires are excellent in tensile strength, fuel economy and wet skid resistance.

[0062]

[Table 13]

[0063]

[Table 14]

[0064]

[Table 15]

[0065]

Examples 4-1 to 4-3],

Comparative Examples 4-1 and 4-2 Samples A and B having modifying groups having affinity for silica shown in Table 1 as raw rubbers
Using a composition of the emulsion polymerization SBR of the sample RC and the natural rubber of the sample RD, the compounding using Q1 shown in Table 3,
Rubber compositions were produced by the kneading methods shown in Table 8-1. The results of measuring the performance as a rubber for a tire tread are shown in Table 8-2. As shown in Table 8-2, Example 4-1 to Example 4 produced by the specific kneading method of the present invention.
Rubber composition of Comparative Example 4-1 to Comparative Example 4-2 obtained by a usual method using a rubber having the same modifying group also in a blend with emulsion-polymerized SBR and natural rubber. As compared with the above, the amount of bound rubber is large and the interaction between silica and rubber is large, the workability represented by the blend Mooney viscosity is good, the tensile strength, fuel economy, wet skid resistance The performance of each tire is excellent.

[0066]

[Table 16]

[0067]

[Table 17]

[0068]

The rubber composition containing a reinforcing silica filler produced by a specific kneading method using a diene polymer having a modifying group having an affinity for silica of the present invention has strength characteristics,
Provided are vulcanized rubber compositions suitable for tire treads and the like having excellent workability, fuel saving performance, wet skid resistance, etc., and vulcanized rubber compositions useful for industrial articles having excellent heat resistance and compression set. You.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C08K 3/36 C08K 3/36 5/00 5/00 // B29K 9:00 B29K 9:00 105: 16 105: 16 (72) Inventor Tokubo Ishimura 1-3-1 Yoko, Kawasaki-ku, Kawasaki-shi, Kanagawa Prefecture F-term in Asahi Kasei Corporation 4F070 AA06 AA07 AA08 AA09 AC23 AE01 AE08 BA02 GA06 GA07 GA08 GB01 GC01 4F201 AA46 AB03 AB11 AB17 AD02 AH20 AR06 BA01 BC01 BC03 BC12 BC37 BD08 BK01 BK14 BK75 BN11 4J002 AC021 AC031 AC071 AC081 AC091 DJ016 FD01 FD07 FD14 FD15 GN01

Claims (14)

[Claims] (A-1) 100 parts by weight of a raw rubber containing a diene rubber-like polymer having a modifying group having an affinity for reinforcing silica, and (B-1) 2 parts of reinforcing silica filler.
5 to 150 parts by weight, and (C) a silane coupling agent in 0.1 parts by weight.
In order to obtain a vulcanized reinforcing silica-containing rubber composition containing 1 to 15 parts by weight, (D) a vulcanizing agent and a vulcanization accelerator in total of 1.0 to 20 parts by weight, (1) first-stage kneading (A-1) 7 of the total amount of the diene rubbery polymer having a modifying group having an affinity for the reinforcing silica
0 to 100% by weight (B-1) 50 to 50% of the total amount of reinforcing silica
A mixture containing 0 to 10 parts by weight of 100% by weight of (C) silane coupling agent with respect to 100 parts by weight of reinforcing silica used at this stage is kneaded at least once at a kneading discharge temperature of 120 to 180 ° C., and then cooled. (2) Second-stage kneading with respect to the first composition obtained in (1), the remaining amount of the component (A-1), the remaining amount of the component (B-1),
(C) at least one of the remaining amounts of the components is added, and
After kneading at least once at a kneading discharge temperature of 180 ° C., the mixture is cooled to obtain a reinforcing silica-containing second composition. (3) As a third step, the second composition obtained in (2) is mixed with (D) ) The total amount of the components is added, the mixture is kneaded at a kneading discharge temperature of 120 ° C or lower, and then cooled to obtain a vulcanizable composition. (4) Reinforcing silica-containing rubber by a method of vulcanizing at a temperature of 130 to 200 ° C A method for producing the composition. 2. (A-1) 100 parts by weight of a raw rubber containing a diene rubber-like polymer having a modifying group having an affinity for reinforcing silica, and (B-1) 25 to 1 parts by weight of reinforcing silica.
50 parts by weight, (C) 0.1 to 1 silane coupling agent
5 parts by weight, a total of (D) component vulcanizing agent and vulcanization accelerator are 1.
In obtaining a rubber composition containing 0 to 20 parts by weight of vulcanized reinforcing silica, (1) First-stage kneading (A-1) Diene rubber having a modifying group having an affinity for reinforcing silica 6 of the total amount of the polymer
0 to 95% by weight, (B-1) 50 to 50% of the total amount of reinforcing silica
100% by weight of the (C) silane coupling agent is added in an amount of 0 to 10 parts by weight based on 100 parts by weight of the reinforcing silica used at this stage, kneading is started, and after reaching a temperature of 100 to 140 ° C, (A-1) ) Add the remaining amount of ingredients and continue kneading,
After kneading at least once at a kneading discharge temperature of 20 to 180 ° C., the mixture is cooled to obtain a first composition. (2) As a second-stage kneading, the first composition obtained in (1) is subjected to (B-1) At least one of the remaining amount of the component and the remaining amount of the component (C) is added, and the mixture is kneaded at least once at a kneading discharge temperature of 120 to 180 ° C., and then cooled to obtain a reinforcing silica-containing second composition. As a third step, a vulcanizable composition is obtained by adding the entire amount of the component (D) to the second composition obtained in (2), kneading at a kneading discharge temperature of 120 ° C. or lower, and then cooling. (4) A method for producing a reinforcing silica-containing rubber composition by a method of vulcanizing at a temperature of 130 to 200 ° C. 3. (A-1) 15 to 99 parts by weight of a diene rubber-like polymer having a modifying group having an affinity for reinforcing silica and (A-2) one or more kinds other than (A-1) 100 to 100 parts by weight of the raw rubber composed of 85 to 1 part by weight of the rubbery polymer (B-1) 25 to 150 parts by weight of the reinforcing silica (C) 0.1 to 15 parts by weight of the silane coupling agent, D) In order to obtain a vulcanized reinforcing silica-containing rubber composition containing a total of 1.0 to 20 parts by weight of a component vulcanizing agent and a vulcanization accelerator, (1) kneading (A- 1) 7 of the total amount of the diene rubbery polymer having a modifying group having an affinity for the reinforcing silica
0 to 100% by weight (A-2) The raw material rubber consisting of 30 to 0% by weight of the total amount of the rubbery polymer other than (A-1) has (B)
-1) 50 to 100% by weight of the total amount of reinforcing silica, (C)
A mixture containing 0 to 10 parts by weight of the silane coupling agent with respect to 100 parts by weight of the reinforcing silica used at this stage is kneaded at least once at a kneading discharge temperature of 120 to 180 ° C., and then cooled to obtain a first composition. (2) Second-stage kneading, with respect to the first composition obtained in (1), the remaining amount of the component (A-1), the remaining amount of the component (A-2),
At least one of the remaining amount of the component (B-1) and the remaining amount of the component (C) is added, and the mixture is kneaded at least once at a kneading discharge temperature of 120 to 180 ° C., and then cooled to obtain a reinforcing silica-containing second composition. (3) As a third step, the entire amount of the component (D) is added to the second composition obtained in (2), and the mixture is kneaded at a kneading discharge temperature of 120 ° C. or lower, and then cooled, (4) A method for producing a reinforcing silica-containing rubber composition by a method of vulcanizing at a temperature of 130 to 200 ° C. 4. (A-1) 15 to 99 parts by weight of a diene rubber-like polymer having a modifying group having an affinity for reinforcing silica, and (A-2) one or more components (A-1) (B-1) 25 to 150 parts by weight of a reinforcing silica containing 85 to 1 part by weight of a rubbery polymer other than
(C) 0.1 to 15 parts by weight of a silane coupling agent,
(D) When producing a vulcanized reinforcing silica-containing rubber composition containing a total of 1.0 to 20 parts by weight of a vulcanizing agent and a vulcanization accelerator, (1) kneading (A-1) ) 50 to 100 parts by weight of the reinforcing silica of the component (B-1) with respect to the total amount of the diene rubbery polymer having a modifying group having an affinity for the reinforcing silica.
0 to 10 parts by weight of the silane coupling agent is added to 100 parts by weight of the reinforcing silica used at this stage, kneading is started, and after reaching a temperature of 100 to 140 ° C,
(A-2) The whole amount of the rubbery polymer as the component is added, and the kneading is continued. The mixture is kneaded at least once at a kneading discharge temperature of 120 to 180 ° C., and then cooled to obtain a first composition. (2) Second stage At least one of the remaining amount of the component (B-1) and the remaining amount of the component (C) is added to the first composition obtained in (1) as kneading, and the mixture is kneaded at a kneading discharge temperature of 120 to 180 ° C. After kneading at least once, the mixture is cooled to obtain a reinforcing silica-containing second composition. (3) As a third step, the total amount of the component (D) is added to the second composition obtained in (2). And kneading at a kneading discharge temperature of 120 ° C. or lower, followed by cooling to obtain a vulcanizable rubber composition. (4) A method for producing a rubber composition obtained by a method of vulcanizing at a temperature of 130 to 200 ° C. 5. The composition of claim 1, further comprising (B-2) 0.1 to 100 parts by weight of carbon black.
2) The total of the components is 25 to 150 parts by weight.
5. The method for producing a reinforcing silica-containing rubber composition according to any one of 4. 6. (A-1) The diene rubber-like polymer having a modifying group having an affinity for reinforcing silica is a conjugated diene rubber-like polymer or a conjugated diene-vinyl aromatic rubber-like copolymer. And a polyfunctional compound having two or more epoxy groups in the molecule.
The method for producing a reinforcing silica-containing rubber composition according to any one of the above. 7. (A-1) The diene rubber-like polymer having a modifying group having an affinity for reinforcing silica is a conjugated diene rubber-like polymer or a conjugated diene-vinyl aromatic rubber-like copolymer. The method for producing a reinforcing silica-containing rubber composition according to claim 6, which is obtained by reacting a polyfunctional compound having two or more epoxy groups and one or more nitrogen-containing groups in a molecule. 8. The process for producing a reinforcing silica-containing rubber composition according to claim 7, wherein the polyfunctional compound is represented by the following general formula (1). Embedded image Here, R ¹ and R ² are a hydrocarbon group having 1 to 10 carbon atoms or ether and / or a hydrocarbon group having 1 to 10 carbon atoms having a tertiary amine, R ³ and R ⁴ are hydrogen, 1 to 10 carbon atoms. 20 hydrocarbon groups or ethers and / or C 1-20 hydrocarbon groups having a tertiary amine, R
⁵ is a hydrocarbon group having 1 to 20 carbon atoms or a hydrocarbon group having 1 to 20 carbon atoms having at least one group among ether, tertiary amine, epoxy, carbonyl, and halogen, and n is 1 to 6 is there. 9. (A-1) The diene rubber-like polymer having a modifying group having an affinity for reinforcing silica is a conjugated diene rubber-like polymer or a conjugated diene-vinyl aromatic rubber-like copolymer. And a compound having a functional group represented by the following general formula (2).
5. The method for producing a reinforcing silica-containing rubber composition according to any one of 5. Embedded image Here, R ⁶ is a hydrocarbon group having 1 to 20 carbon atoms or a hydrocarbon group having 1 to 20 carbon atoms having at least one group among ether, tertiary amine, epoxy, carbonyl, and halogen. 10. The compound having a functional group represented by the general formula (2) is an N-alkyl cyclic lactam compound,
The method for producing a reinforcing silica-containing rubber composition according to claim 9, which is an -alkyl cyclic urea compound or an N-alkylbenzophenone compound. 11. (A-1) The diene rubber-like polymer having a modifying group having an affinity for reinforcing silica is a conjugated diene rubber-like polymer or a conjugated diene-vinyl aromatic rubber-like copolymer. The method for producing a reinforcing silica-containing rubber composition according to any one of claims 1 to 5, which is obtained by reacting a polyfunctional compound having two or more alkoxy group-containing silanes in the molecule. 12. The polyfunctional silane compound containing two or more alkoxy groups in the molecule, wherein the compound further contains an alkylamino group or an epoxy group in the molecule.
A method for producing the reinforcing silica-containing rubber composition according to the above. 13. (A-1) A conjugated diene-vinyl aromatic rubber-like copolymer having a modifying group having an affinity for reinforcing silica has a vinyl aromatic compound having a block bonding amount of less than 4%. The method for producing a reinforcing silica-containing rubber composition according to any one of claims 6 to 12, which is a random copolymer. 14. (A-1) A conjugated diene-vinyl aromatic rubber-like copolymer containing a modifying group having an affinity for reinforcing silica, wherein the vinyl aromatic compound has a block bonding amount of 4% or more. 6. A block copolymer of 30% by weight.
3. The method for producing the reinforcing silica-containing rubber composition according to any one of 2.