JPS6399248A - Rubber composition - Google Patents

Abstract

PURPOSE:To obtain a rubber composition having balanced processability, abrasion resistance, wet skid resistance, etc., and suitable for various kinds of vulcanized rubber such as tire, etc., by compounding a specific styrene-butadiene copolymer with a specific polybutadiene, etc. CONSTITUTION:(A) A styrene-butadiene copolymer having a styrene-content of 10-60wt% and a bonded vinyl content in the butadiene segment of 60-80% is compounded with (B) a polybutadiene having a bonded vinyl content of 25-95% and (C) a rubbery conjugated diene polymer other than the components A and B (e.g. natural rubber, polyisoprene rubber, etc.). The amounts of the components are selected to give a weight ratio (A:B) of 20-80:80-20, preferably 25-75:75-25, a weight ratio of the component C to the sum of the components A and B of 100-25:0-75, a styrene content in the mixture of A and B of 10-50wt% and a bonded vinyl content in the butadiene segment of 60-80%.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a rubber composition containing a styrene-butadiene copolymer having a specific structure and a polybutadiene having a specific structure. It is a composition suitable for each rubber application with excellent processability and dynamic properties.

In addition to conventional natural rubber and styrene-butadiene copolymer rubber obtained by emulsion polymerization, the raw material rubber used in various vulcanized rubber products such as automobile tires, anti-vibration rubber, and footwear includes: With the development of polymer polymerization technology, various types of melt polymerized rubbers, such as Zieg
Polyimprene rubber, high cis-polybutadiene rubber, ethylene-
Examples include propylene copolymer rubber, low cis-boridetadiene rubber obtained by polymerization using a lithium catalyst, and styrene-butadiene copolymer rubber, which can be used singly or blended. Used as a raw material for German vulcanized rubber products.

Among the various solution-polymerized rubbers mentioned above, polybutadiene rubber and styrene-butadiene copolymer rubber obtained using lithium-based catalysts can be used, for example, as additives for catalysts such as ether, thioether, 6th-class amine, and hexitemethyl phosphor. By adding polar substances such as lutriamide, specific polymers with different microstructures of the butadiene moiety can be obtained,
It is a polymer that has been attracting attention in recent years because it is possible to change the polymer structure by changing the method of adding monomers, such as obtaining random copolymers and block copolymers.

Among the polymers obtained using these lithium-based catalysts, Japanese Patent Publication No. 49-4311 describes polymers with a microstructure of 1,2
- Bond (synonymous with vinyl bond) amount: 25-50%, 1,4
- Rubber compositions for tires using polybutadiene having a trans bond content of 15 to 55% and a 1,4-cis bond content of 10 to 40% are disclosed. When polybutadiene with such a microstructure is used in tire treads, it exhibits satisfactory abrasion resistance and wet skid resistance (slip resistance on wet road surfaces), but on the other hand, it is difficult to process or mold the rubber. The workability was not necessarily satisfactory.

On the other hand, the styrene-butadiene copolymer produced by polymerizing styrene and butadiene using a lithium-based catalyst in the presence of a polar substance such as an ether or 6th class amine is superior to that obtained by polymerizing without using a polar substance. A rubber composition for a H7t tire using a styrene-butadiene copolymer having a large amount of vinyl/I/bonds, for example, 20 to 60%, has a vinyl bond content of 20% to 60%. General low cis-boridetadiene and vinyl bond amount is 20%
Compared to the nostyrene-detadiene co-polymer, there are problems with wear resistance and other issues.

Furthermore, in recent years in the rubber industry, vulcanization has been carried out at higher temperatures and shorter times than conventional vulcanization conditions in order to improve productivity. However, when vulcanization is performed at a high temperature for a short time, there is a difference in the vulcanization state between the center and the outside of the molded product due to heat conduction, resulting in over-vulcanization on the outside. Problems such as the phenomenon of so-called "cure recovery" occurring frequently and deterioration of the physical properties of the vulcanized product occur. For this reason, there has been a demand for a raw material rubber that has less vulcanization relapse and can be vulcanized at high temperatures and in a short period of time. The results showed that a rubber composition containing a specific styrene-detadiene copolymer and a specific polycitadiene, as well as other rubber-like substances, showed a good balance between processability, abrasion resistance and wet skid resistance, and vulcanization. A rubber composition that exhibits little re-scattering during vulcanization and has other excellent properties,
We have discovered that it is suitable for various vulcanized rubber applications including tire applications, and have arrived at the present invention.

The present invention consists of (A) component: a thealstyrene-detadiethyl copolymer with a styrene content of 10 to 60% by weight and a vinyl bond content of the butadiene moiety of 60 to 80%; (81 components: a vinyl bond content of 25%); ~95% of polycitadiene, (C) component: A rubber composition using the above-mentioned recovered portion or a comb-like polymer other than the fBl component as a raw material rubber, and the summer-to-sum ratio of the recovered portion and the +81 component is 20~95%. 80:80-20 a.m.
The weight ratio of the total amount of LAI component and component (B) to component (C) is 100 to 25:0 to 75. This is a rubber composition for vulcanization that contains a vulcanizing agent.

The styrene-butadiene copolymer used in the recovered portion of the present invention has a styrene content of 10 to 60%, preferably 10%.
The amount of the copolymer is between 15% and 55%, particularly preferably between 15% and 50%. If the styrene content is less than 10% by weight, Ik%, processability will be insufficient and the resulting rubber composition will have poor tensile strength and wet skid resistance. On the other hand, when the above amount exceeds 60% by weight, the resulting composition has a
Abrasion resistance becomes insufficient.

The vinyl bond cap (1,2-bond amount) of the butadiene portion of the recovered styrene-butadiene copolymer was 60 to 80%,
Preferably it is in the range of 60 to 70%. If the vinyl bond amount is less than 60%, the resulting composition will have insufficient skid resistance, and if it exceeds 80%, the composition will have poor abrasion resistance.
Resilience is poor.

(5) A polymer in which styrene in the styrene-butadiene copolymer as an ingredient exists uniformly along the molecular chain, a polymer in which the amount of styrene increases or decreases along the molecular chain, and the amount of styrene A copolymer with a large amount of styrene or a block copolymer having one or more blocks consisting of polystyrene and a copolymer with a small amount of styrene or one or more blocks consisting of polybutadiene, etc. Any copolymer may be used. The amount of polystyrene in (J, Polym Sc
i 1429<1946)) is 5 of the copolymer! % or less is preferable from the viewpoint of exothermic properties of the resulting composition.

In addition, like the styrene mentioned above, copolymers in which the vinyl bonds in the butadiene moiety are uniform along the molecular chain, copolymers in which the vinyl bonds increase or decrease, and parts with many and few vinyl bonds in block shapes are also available. Any of the existing copolymers can be used as component (A) of this invention'.

The number average molecular weight of the styrene-butadiene copolymer as component (A) is preferably from so, o o to 400,000.
゜More preferably, it is 75,000 to 300.0130, and the molecular weight distribution (ratio of weight average molecular weight (Mw) to number average molecular weight [excitation] <Mw/yn)) is preferably 1
．． 1 to 4.0, preferably 1.2 to 3.0.

A) component and the component described below (including 100 parts of the total amount of Bl component) are 20 to 80 parts by weight, preferably 2 parts by weight.
They are used in a composition of 5 to 75 parts by weight, and outside the above composition range, the effect is slight compared to when each is used alone.

The polybutadiene (Bl component) of the present invention has a vinyl bond content of 25 to 95%, preferably 25 to 70%. If the vinyl bond content is less than 25%, wet skid resistance and In addition to poor processability, vulcanization is likely to occur during the vulcanization process of the obtained composition.If the above amount exceeds 95%, the abrasion properties, anti-shock elasticity, etc. of the obtained composition will deteriorate. becomes a problem.

Furthermore, (the number average molecular weight of the polybutadiene ingredient is
It is preferably 50,000 to 400,000, more preferably 75,000 to 300,000, and the molecular weight distribution is preferably 1.1 to 4.0, more preferably 1.
．． It is 2 to 3.0.

(B) component is (Aj acid component (total amount of subcomponents 1ooM
20 to 8 parts, preferably 25 to 7 parts, based on the spear part
It is used in a composition of 5 parts by weight.

In the present invention, component 8) and component (B) are used within the above composition range, but preferably component (5) and component (B)
Styrene-containing 9 or 10 as a mixed composition with ingredients
~401 Mayuzumi, the vinyl bond amount of the butadiene moiety is 35 ~
It is convenient to use the structures and compositions of the styrene component and the iBl component such that the content is 80% in terms of the processability and abrasion resistance of the resulting composition.More preferably, the styrene content is 15 to 65%, and the vinyl bond content is 40 to 70%.

The styrene-butadiene copolymer (J component) and the polybutadiene (Bl component) can be used as the raw rubber component of the present invention, regardless of the production method, as long as they meet the above-mentioned limiting conditions.

(A + skin component styrene-butyl lithium co-monomer is manufactured by using an organic lithium such as n-butyllithium or 5ec-butyllithium as a polymerization catalyst in an inert solvent such as hexane, cyclohexane, or benzene. If necessary, other organic compounds such as alkoxides such as potassium butoxide and organic acid salts such as dodecylbenzene sulfonate are used as co-catalyst components, and as compounds that connect the vinyl bond M, ether, polyether, It can be obtained by copolymerizing styrene and butadiene using a polar compound such as a 6th class amine, a polyamine, a thioether, or hexamethylphosphorotriamide.The above polymerization process can be a batch polymerization process, a continuous polymerization process, or may be any of nine combinations.

Furthermore, branched or radial copolymers can be obtained by coupling a polymer chain containing a t-active end obtained by the above method with silicon tetrachloride, tin tetrachloride, divinylbenzene, or the like. MatS Said 1
Based on one method, adjust the monomer addition method,
Vinyl bond - By changing the polymerization conditions, such as changing the pigment group during polymerization, the styrene content and the amount of vinyl bond in the molecular chain can be continuously increased or decreased. , it is also possible to obtain a cylindrical shape. Mat1 acetylene, 1゜2-butadiene,
Various molecular weight regulators such as fluorene, primary amine, and 241 amine are also used.

Mano (The manufacturing method of polybutadiene used as a subcomponent is
Polybutadiene of various structures can be obtained by homopolymerizing butadiene in substantially the same manner as for the styrene-butadiene copolymer of component (5), and further by the above-mentioned post-treatment method.

Next, the rubbery 1 polymer of the tC) component used in the rubber composition of the present invention is the rubbery conjugated diene polymer other than the Bl component, and the + component and the rubbery conjugated diene polymer other than the Bl component. Any material can be used as the tC) component of the present invention as long as it can be mixed with the fraction, preferably natural rubber, polyisoprene, or styrene with a content of D to
Polybutadiene or styrene with 60 wt%
Polyisoprene is preferably used as a natural rubber compound made from a butadiene copolymer.

The above-mentioned natural rubber, polyisoprene, polydetadiene-matahastyrene-butadiene copolymer are raw rubbers that are generally used for rubber applications.

In the rubber composition of the present invention, the rubbery substance of the component (C), the component (A) and the (Bl component) are the K+ component and the (Bl component).
Total amount of subcomponents: 25-100 parts by weight, component (C): 75-100 parts by weight
0 parts by weight, preferably the total Bt amount of the four components and component (B) 6
0~100. mfi part, (C) component 70 to O heavy image part, total amount of (A) component, (BI acid component Ic) component 10
0M parts are used in the composition.

(8) If the total amount of the component and the fBl component is less than 25Jit, then
The improvement effect on backlash is slight.

Next, the percentage characteristics of the rubber composition obtained by Kinoe 8AK will be described.

Four components of the rubber composition of the present invention and two components, the fBj component?
The characteristics of (111Alb) when used as raw material rubber are
i, abrasion resistance compared to 1 when using only the raw material rubber,
Excellent rebound elasticity.

f2J fBl component alone f! : Excellent workability and wet skid resistance compared to raw rubber binding.

(3) Compared to a composition using a styrene-butadiene copolymer having component (A) + (styrene-containing 'Hk corresponding to the Bl component and a vinyl bond amount), Excellent balance of wet skid resistance and excellent workability.

(4) Emulsion polymerized styrene-butadiene copolymer rubber, vinyl 1m obtained by solution polymerization t iE 15
Compared to compositions using styrene-butadiene rubber or y-butadiene rubber as the raw material rubber, the wet skid resistance is greatly improved and the vulcanization during the processing process is improved.

There is a thing called K.

In addition, the characteristics of a rubber composition in which component (C) is added to components (A) and (B) are as follows: fil natural rubber, polyisoprene, polybutadiene used in component (C), and styrene. It has the effect of improving vulcanization failure of butadiene copolymer.

As shown above, the rubber composition according to the present invention is a useful rubber composition that could not be achieved by using conventional raw material rubber or a combination of conventional raw material rubber. Suitable for footwear, etc. It is particularly suitable for tire treads because of its excellent abrasion resistance and wet skid resistance.

The rubber composition of the present invention has the above-mentioned (Al component, (Bl component,
Component C) is a raw material rubber, and by adding various compounding agents to it and vulcanizing it, it can be used for various uses including tires.

Compounding agents added to the above rubber composition include reinforcing agents, softeners, fillers, vulcanizing agents, vulcanization accelerators, vulcanization aids, scorch inhibitors, anti-aging agents or antioxidants, and tackifiers. additives, colorants, heat retardants, lubricants, foaming agents, and other compounding agents, which are appropriately selected and used as required.

Typical reinforcing agents include carbon black, and various types of reinforcing agents with different particle sizes or stractures made by various ridge-building methods are used, including l8AF, R.
Carbon blacks such as AP and FHF are suitably used for applications centered on tires.

The amount of carbon black to be added is determined by taking into consideration the addition of process oil used at the same time, but the amount of carbon black added is
10-150 for 00MJL club! Volume, good 2L (
is used in an amount of 20 to 100 parts by weight. 'S' and addition & of the above-mentioned carbon black are appropriately determined according to the purpose of use of the rubber composition, and two or more types may be used in combination.

Other reinforcing agents used include inorganic reinforcing agents such as silica and activated calcium carbonate, high styrene resins, and phenol-formaldehyde resins.These inorganic or organic reinforcing agents are added to 100 parts by weight of raw rubber. Against 0.
5 to 100 parts by weight, preferably 1 to 50 parts by weight are used.

Typical softeners that are added as needed include process oil, paraffin, naphthenic, and aromatic threads, which are preferably used for rubber max.
2 to 100 parts by weight, preferably 5 to 70 parts by weight
Used in heavy duty. It is also possible to use an oil-extended polymer in which process oil is added to the raw rubber in advance. Other softeners include liquid paraffin, coal fi
-/I/, fatty oil, sub, etc.

As a filler, calcium carbonate, clay, Merck,
Examples include aluminum.

Typical vulcanizing agents are sulfur and raw rubber 1.
It is used in an amount of 0.1 to IQiff parts, preferably 0.2 to 5 parts by weight, per 00Nfjk parts. Other vulcanizing agents include sulfur compounds such as sulfur chloride, morpholine disulfide and alkylphenol disulfide, and sulfur compounds such as peroxide, which may be used alone or in combination with sulfur.

A wide variety of vulcanization accelerators can be used, and these can be used in an amount of 0.01 to 5 parts by weight per 100 parts by weight of N family dem, and two or more types can also be used in combination. Typical vulcanization accelerators include guanidine, aldehyde-amine and aldehyde-ammonia, thiazole, imidacillin thread, thiourea, thiuram, dithiocerbamate, dentate, and mixed accelerators. It will be done.

Examples of vulcanization aids include gold compounds such as zinc oxide, fatty compounds such as stearic acid, and amines. be done.

Typical anti-aging agents or antioxidants added as needed are amine-based, phenol-based, phosphorus-based, etc., and these are added in amounts of 0.001 parts per 1001 parts of raw rubber.
001 to 10 parts by weight, and two or more types may be used in combination.

Typical scorch inhibitors to be added as necessary include fumeric anhydride, salicylic acid, and donitrone diphenylamine. 0 overlapping section is used.

Furthermore, as a tackifier to be added as necessary,
Coumarone-indene resin, terpene-phenolic resin,
Typical examples include rosin ester, raw material rubber 10
0.1 to 10 parts are used per 0 weight 1a part.

Furthermore, each of the other additives may be added to the rubber composition as needed.

The rubber composition of the present invention is produced by mixing raw rubber and each of the compounding ingredients using various mixing devices generally used for mixing rubber compositions, such as an open roll, a Banbury mixer, a kneader, and an extruder. Then, after being molded into the desired shape, it is vulcanized.

The rubber paraboloid of the present invention is suitable for use in tires for various automobiles such as trunks, buses, passenger cars, and small cars, industrial goods such as belts, hoses, anti-vibration rubber, footwear, daily necessities, construction materials, and other various uses. It is kept alive and used for sutra communication.

Examples are shown below, but these are intended to more specifically explain the present invention, and are not intended to limit the scope of the present invention.

Reference Example A typical example of the method for polymerizing the styrene-butadiene copolymer and polybutadiene used in the present invention is shown below.

fil In the case of sample A-3, one polymerization reactor with an internal volume of 10 stones equipped with a stirrer and a jacket was used, and the internal temperature of each batch was maintained at 98 to 102 °C.
Add 24 g of butadiene as p monomer to the bottom of the reactor.
min % styrene as 8.59/min Hexane as bath medium k 150! / min.

2.6g/tetrahydrofuran as a polar compound
n-butyllithium as monomer 1 as a min
Polymerization reaction by continuously supplying 0°066g to 00g using a metering pump? Start the reaction and continuously withdraw the polymer solution from the top of the reactor. After reaching a steady state, 0.5 parts by weight of di-tert-butyl-P-cresol per 100 N parts of the polymer was added to the resulting homopolymer G solution, and after t, the hexane solvent was removed to obtain fto-superior 7. The analytical values of the polymer are as shown in Table 1.

The microstructures of the styrene-containing adhesion and butadiene moieties were measured using an infrared spectrophotometer and calculated by Hangton's method.

When sample A-3 was analyzed by G, P, and C, the weight average molecular weight (Mw) was 343,000, the number average molecular weight (Mn) was 163,0011, and Mw/Mn-2.1.
In addition, G, P, and C are Shimadzu's Kema LC-1.
The measurement was carried out using a mold, a differential refractometer as a detector, tetrahydrofuran as a solvent, one each of H#S#G-50, 60, and 70 columns, and a temperature of 40°C.

(2) Using the polymerization reactor of Sample A-4 with an internal volume of 402 mm and a stirrer and a jacket, 18.2 kg of cyclohexane, 2.9 kg of butadiene, 1.6 U of styrene, 7.0 g of diethylene glycol dimethyl ether, Add 6.0 g of n-butyllithium, maintain the reactor internal temperature at 45 to 55°C, and polymerize for 1 hour. After the polymerization is complete, 3.0 g of silicon tetrachloride is added to the polymer bath liquid to conduct the coupling reaction. I made him do it. Add 100 parts by weight of polymer to this polymer solution.7? : 90.5 parts by weight of g-tert-butyl-P-cresol was added.
After that, the helium was removed and sample A-4e was obtained. The analytical values for sample person-4 are shown in Table 1. I7? : Mw of sample A-4=284.
000 Mn-164, OLI O, MW/Mn=1.
Atsushi at 73.

Table 1 shows the analytical values of the styrene-butadiene copolymer used in the present invention along with A-3 and A-4.

Among these, A-1-h-2e A-5e A-
6, A-7, and A-8 were prepared using the same polymerization method as sample A-3 and sample A-4, but by simplifying the amount of butadiene and styrene supplied, the amount of catalyst, the amount of polar compound added, the polymerization temperature, etc. That's what I got. In addition, samples a-1 and a-2 are specific polymers obtained by the continuous polymerization method used to obtain sample A-3 without using a vinylizing agent), and sample a-3 is a commercially available emulsion polymer. It is a polymerized styrene-butadiene copolymer (SBR-1502).

In addition, Table 2 shows the analytical values of the polybutadiene used in the present invention, and samples B-1 to B-<5 were obtained by a polymerization method using a vinylating agent containing samples A-3 or A-4. Butadiene is the only monomer! Sample b-1 is a commercially available low-cis polyamide (Diene-5OR), and ERb-2 is a commercially available high-cis polyamide (Diene-1220). It is. Note that the microstructure of polybutadiene was calculated by measuring the spectrum using an infrared spectrophotometer and using the Morello method.

! Example 1 Each polystyrene-butadiene copolymer shown in Table 1 and each polydetadiene shown in Table 2 were used, and these polymers or their compositions shown in Table 6 were made into rubber. The ingredients were mixed using a Banbury mixer according to the blending method shown in Table 4, and the mixability in the Banbury mixer was good in all cases. Mano These blends were made into a sheet of a predetermined thickness using a heated roll (8 inches), a ribbon of duck was made, and the extrusion processability was evaluated using a Garvey die extruder. The evaluation results of workability are shown in Table 3.

Nine, these formulations were pressed at 140°C with 11rJ
``A, and its physical properties were measured and shown in Table 6.''

Below, we will discuss the results shown in Figure 6.

Example 1 is a composition in which sample A-4 and sample B-2 are blended to form a nine-rubber all-rubber component. The composition of Comparative Example 1-6 using Sample A-4 had good wet skid resistance but poor ffIIt resistance. The composition of Comparative Example 1-4 using Sample B-2 had Although it has good abrasion resistance, it has physical property problems such as inferior wet skid resistance and tensile strength. Does it have an excellent balance of resistance and sufficient tensile strength as a rubber composition? have.

Moreover, Comparative Examples 1-5 are controls for this evaluation. The blended rubber component of Example t has substantially the same styrene content and microstructure as rubber component A-4 used in Comparative Examples 1-5. The composition of Example 1 has the same #abrasion properties as the compositions of Comparative Examples 1-5, has improved wet skid resistance, and has good workability in awns.

Furthermore, the composition of Example 1 is an a-
Compared with the compositions of Comparative Examples 1-6 and 1-7 in which 1, a-2 was used, and the composition of Comparative Example 1-8 in which commercially available emulsion polymerized styrene-butadiene copolymer was used. tl The wet skid resistance has been greatly improved, and the processability is also the same or better.

It can be said that the composition of the present invention has excellent processability and mechanical properties.

□Bottom margin table 4 Rubber 100 parts by weight Aromatic process oil 5I ISAF number Carbon black 45 N
Stearic acid 21 zinc oxide 4N anti-aging agent B-1
1 l vulcanization accelerator CZ”2
1 I sulfur 1.
71"1 Reaction product of diphenylamine and a7ton"2N-
Cyclohexylbenzo? 7 Solsulfenamide Example 2 Using the formulation shown in Table 4, a rubber composition containing the polymer or blend of polymers shown in Table 5 as the rubber component was prepared in the same manner as in Example 1. I decided on a method. Table 5 shows the measurement results of these vulcanizate physical properties.

In Table 5, a rubber composition using Sample A-2, which was used as a comparative example in Example 1, was used as a control. However, some of the results in Example 1 are also included in Table 5 for reference.

The constant composition using the rubber component within the scope of the present invention of Fuzetsuta 2 has improved abrasion properties compared to the composition of Comparative Example 1-5 using the control A-2.

On the other hand, the compositions of Comparative Examples 2-1 to 2-5 and Comparative Example 1-2 using the rubber component alone used in these Examples had a lower temperature than the control composition of Comparative Example 1-5. The relationship between wet skid resistance and abrasion resistance is the same or lower, and the composition of Comparative Example 2-4.2-5.1-2, which uses polybutadiene as a rubber component, has inferior tensile strength. .

Furthermore, as component (A), styrene-
The compositions of Comparative Example 2-6 using a butadiene copolymer and Comparative Example 2-7. It has poor wet skid resistance and poor heat generation.

Example 3 As component (C), C-1 (Natural Go (A)) shown in Table 6 was used.
) C-2 (polyisobrene rubber) and a-2 (styrene-butadiene rubber (A) b-1 (t cis-phosphoriftadiene rubber Lb-2c using high-cis polydetadiene rubber (A), Table 7 shows 3 of the A component shown, the (D component), and the (C) component.
The rubber composition was maintained in the same manner as in Example 1 by using the rubber component as the surface portion and the compounding treatment shown in Table 4. When using the rubber components shown in the examples in Table 7, all of them had good blendability with component C.

Table 7 shows the physical properties of the vulcanized products and the results of measuring the vulcanization properties of these rubber compositions.

As shown in Table 7, a composition using a styrene-pumediene copolymer with a small amount of vinyl in Comparative Example 3-6, a composition using the j component of the present invention as in Comparative Example 6-6, fB+M, A composition using polybutadiene with a low VC-vinyl bond k by 1 Bli as in Comparative Example 6-7, a composition with a low natural rubber I9, has a "low effect" on preventing the D sulfur melting of polyisoprene rubber. However, Example 3-1.3-2.3-3.
All of the compositions of the present invention have less vulcanization re-dishing and (
It is sufficiently effective in preventing uncuring of the comb component used in component C).

Also, the composition of Example 6-1 has better wear resistance than the composition of Comparative Example 6-1, and the composition of Actual Example 6-2 has better wear resistance than the composition of Comparative Example 6-2. It has excellent wet nukirad resistance.

Table 6

Claims (1)

[Claims] 1. Component (A): styrene content is 10 to 60% by weight;
Styrene-butadiene copolymer (B) component with a vinyl bond amount of 60 to 80% in the butadiene moiety: Polybutadiene (C) component with a vinyl bond amount of 25 to 95%: The above (A) component or (B) component Component (A) and component (B
) The weight ratio of the components is 20-80:80-20, and (A
A rubber composition in which the weight ratio of the total amount of component () and component (B) to component (C) is 100-25:0-75. 2. Claim 1, wherein the polymer composition obtained by mixing component (A) and component (B) has a styrene content of 10 to 50% by weight and a vinyl bond content of the butadiene moiety of 60 to 80%. The rubber composition described. 3. The weight ratio of component (A) and component (B) is 25 to 75:
75 to 25, the rubber composition according to claim 1. 4. Component (C) is one or more selected from natural rubber, polyisobrene, polybutadiene with a styrene content of 0 to 60% by weight, and a vinyl bond content of the butadiene portion of 1 to 20%, or a sterene-butadiene copolymer. The rubber composition according to claim 1. 5. Claim 4, wherein component (C) is natural rubber.
The rubber composition described in . 6. The rubber composition according to claim 4, wherein component (C) is a polyisoprene rubber having a cis-1,4-bond content of 85% or more. 7. Component (A): Styrene content is 10 to 60% by weight,
Styrene-butadiene copolymer (B) component with a vinyl bond content of 60-80% in the butadiene moiety: Polybutadiene (C) component with a vinyl bond content of 25-95%: Natural rubber, polyisobutylene, styrene content 0 ~60% by weight and one or more rubber-like conjugated diene polymers selected from polybutadiene or styrene-butadiene copolymers having a vinyl bond content of 1 to 20% in the butadiene moiety as a raw material, component (A) and ( B) The weight ratio of the components is 20~
80:80-20, the weight ratio of the total amount of component (A) and component (B) to component (C) is 100-25:0-75, and further, component (C): Reinforcing agent (E) component: vulcanizing rubber composition containing a vulcanizing agent