DESC:
FIELD OF THE INVENTION
The present invention relates to Rubber Composition with improved dispersion properties achieved through fillers in combination with coupling agent, wherein the Coupling agents with bifunctional motifs efficiently improve dispersion of carbon black filler in the rubber compositions. The present invention also relates to coupling agents with bifunctional motifs in which an efficient class of Mercapto derivatives of aromatic amine-based carbon black coupling agent is added along with reinforcing filler at the non-productive stage of the rubber compounding process. The present invention further relates to a reduction in the mixing stages of rubber composition exhibiting improved dispersion of carbon filler in the rubber compound thereby improving the properties. The present invention includes an article of manufacture, including a tire, non-tire, having at least one component comprised of such rubber composition.

BACKGROUND OF THE INVENTION
In recent years, the key focus in case of manufacturing of Rubber articles, especially Tires is on the reduction of rolling resistance in the Automobile Industry, as it improves fuel efficiency and reduces carbon dioxide emission. The causes of rolling resistance are attributed to three forms of energy loss viz. energy loss due to tire deformation namely hysteresis loss, energy loss due to friction of the tire thread against the road surface, and energy loss due to air resistance of tire rotation. However, the significant contribution to rolling resistance is due to tire deformation or hysteresis loss. The factors responsible for hysteresis loss are i) friction caused by a cyclical tire deformation due to the flexibility of polymers, ii) friction due to polymer and filler; iii) the friction between filler-filler interaction.
Currently, SBR/BR/-silica based compounding systems (Green Tires) with a higher silica filler loading along with silica coupling agents are popularly used in the rubber industry and are known to provide good dispersion/ bonding of silica with rubber. Natural rubber-carbon black (NR – CB) compounding systems are also extensively used in various sections of Tires due to their high elasticity, durability, and high load-bearing capacity. But such Natural rubber -Carbon black (NR – CB) compounding systems are not as fuel and energy-efficient as it involves multistage mixing for better dispersion of carbon black in rubber matrix and therefore the demand for fuel and energy savings in NR-CB compounding systems in Tire manufacturing is increasing. The rolling resistance of such a system can be reduced by effective dispersion and bonding between CB and the rubber. Poor interaction between carbon black filler and the rubber leads to deteriorated physical and dynamic properties of the vulcanizate, in particular, increased hysteresis and increased heat build-up. There is therefore a need for improved carbon black dispersion in Rubber to improve both the physical and processing characteristics of Rubber compounds. Particularly, the finer particle size of carbon black requires more (three or four) mixing stages for proper dispersion and control of the viscosity for further processing. So, there is a need in the tire manufacturing industry to have strategies for carbon black dispersion in the rubber matrix with a reduction in mixing stages and Viscosity of rubber composite.
Three methodologies including surface modification of carbon black (e.g. Part et.al, Oxygen plasma treatment on Surface and Mechanical Properties of Carbon Black/Rubber Composites, Carbon, 2003, 41, 1437-1442), functionalization of rubber (e.g. Functionalized Liquid Butadiene Rubber as a Processing Aid; Sanghoon Song et.al. Polymers 2022, 14, 3343), and incorporation of the interfacial modifier (e.g. Han et.al, Effect of coupling agents on the vulcanizate structure of carbon black filled natural rubber, Composite interface, 2020, 27, 355-370) have been used to improve the dispersion of carbon black in rubber.
Continuous effort is being made by incorporating various processing aids with high dosages (additives) to achieve better mixing and reduce viscosity in mixing stages, however in these cases, no chemical bonding occurs between carbon black and rubber, therefore, the final performance of the product did not improve, but there is a risk of the blooming of these additives on the rubber surface.
Carbon black coupling agents have been explored to achieve good efficiency in terms of reduction of hysteresis loss and heat build-up, resulting in good fuel savings. US Pat. No.2315855 (1943) by Howland et al discloses that N,4-dinitroso – N-methyl aniline is useful as a coupling agent for carbon black and provides better dispersion in NR/CB compounding system. Walker et al (J. Org. Chem. 1962, Vol. 27, 2767) disclose that N-(2-methyl -2-nitropropyl-)-4-nitrosoaniline acts as a coupling agent for carbon black and reduces hysteresis loss. Yamaguchi et al (Rubber World, Feb.30 (1989)) described a coagent called Sumifine (N, N’-bis(2-methyl-2-nitropropyl)-1,6-diaminohexane that could significantly reduce hysteresis loss and good fuel savings performance. But all these aforesaid coupling agents are not used commercially due to their toxicity/carcinogenicity issues.
Datta et. al. (US Patent No. 2,809,971) described use of Zinc Pyrithione (ZPNO i.e., Zinc salt of pyridine -2-thiol -N-oxide) as an effective carbon black coupling agent for polyisoprene rubber and carbon black. Narita et. al. (US 2009/0043014 A1) also described the reduction of heat build-up and fuel savings using ZPNO with a modified mixing strategy. Shikoku Chemicals Corporation (EP 2738208A1) describes the coupling agents for rubber and carbon black. Recently, Sumitomo Chemical Co. Ltd. proposed two compounds (Tradename SUMILINK 100 i.e., 3-Amino propyl thiosulphonic acid & SUMILINK 200 i.e., N-substituted maleic acid sodium salt of paraphenylenediamine) for good dispersion of various grades of carbon black in rubber. Also, M. Galimberti et.al (ACS Sustainable Chemistry & Engineering, 2023, 22, 2713-2726) reported 2-(2,5-dimethyl-1H-pyrrol-1-yl)-1,3-propanediol (Serinol pyrrole) as a universal coupling agent for carbon black. Recently, Liqun Zhang et.al. reported amino functionalized polysulfide for improved dispersion (Chem. Mater. 2023, 35, 764-772 and CN202210056309.7) of carbon black in natural rubber, However, our studies on the material cited in the research article that the processing parameters showed no reduction in compound Mooney viscosity and lower scorch safety, thereby affecting processing characteristics of the compound and further processing difficulty while manufacturing rubber article.
Dispersion of carbon black in the polymer (rubber) is very essential step to improve the processing of rubber compounding and improve the performance of rubber products. Surface modification of carbon black and rubber surfaces to have better dispersion is challenging as it involves pre-treatment and chemical modification. Thus, the use of a coupling agent during the rubber compounding process for better dispersion of carbon black in rubber is a practical & economical approach. In the past, nitroso aniline and derivatives have been reported as carbon black coupling agents, but these compounds are not in practice due to their toxicity and carcinogenicity issues. Though few coupling agents have been highlighted in the literature as disclosed previously; the Rheological properties of some compounds are not desirable for rubber compounds and are not easily available commercially. Higher dispersion of carbon black in rubber can reduce the mixing cycles and rubber compounding time, and therefore there is a high demand for the same.
The inventors of the present invention have surprisingly found that by incorporating a suitable coupling agent in the non-productive stage of rubber compounding, the number of mixing stages/ cycles are reduced. As the viscosity of the non-Productive rubber compounds is significantly reduced it does not require remixing (re-pass) to reduce the viscosity of the compound for ease of further processing. Also, the coupling agents as disclosed in the present application are easy to commercialize and also meet the current requirements of improving the dispersion of carbon black.

OBJECT OF THE INVENTION
It is an object of the invention to provide rubber composition with improved dispersion of fillers such as carbon black in the rubber matrix.
It is an object of the invention to provide coupling agents which can improve the dispersion of reinforcing filler (Carbon black) used in rubber composition.
It is an object of the invention to provide rubber composition with improved carbon black dispersion in the rubber matrix.
It is another object of the invention to provide a rubber composition comprising of reinforcing fillers coupled with coupling agents with bifunctional motifs [A] having both amino- and mercapto-functionality.
It is an object of the invention to reduce the mixing time of the non-productive stages in rubber compounding process by eliminating the remixing (re-pass) stage.
It is an object of the invention to reduce the mixing stages in the rubber compounding process.
It is an object of the invention to provide a rubber compounding process with reduced rolling resistance, and reduced heat-built up.
It is another object of the invention to provide a rubber compounding process, with reduced mixing stage/time, better carbon black dispersion, low heat-build-up, good processability, and improved Physical, Rheological & Dynamic properties.

SUMMARY OF THE INVENTION
According to one aspect of the invention, the present application provides a Rubber composition comprising:
a diene elastomer; a vulcanization agent, an anti-degradant agent; reinforcing filler such as carbon black alone or in combination with other filler and coupling agent, wherein the coupling agent is a compound having the following formula [A]:

wherein,
n is 2, 3 4 i.e. Sulfide linkage is di-, tri- or tetra- alone or a mixture thereof;
R1 and R2 independently represent are -H, Alkyl chain of C1-C20 carbon chain which is substituted with alkyl or carboxylic acid or esters or -OH or anhydride or alkali salt or reactive functional group and the
NR1, R2 are position at ortho or para position with respect to sulfide chain.
According to another aspect of the invention, the present application provides a coupling agent for enhancing dispersion properties of carbon black filler, comprising a mercapto moiety and an amine moiety and having the formula:

M: Na /K

M: Na / K

According to yet another aspect of the invention, there is provided a Rubber composition comprising 100 parts by weight of the diene rubber components, 0.1 to 3.0 parts by weight of sulfur or insoluble sulfur or polymeric sulfur or/ and combination thereof, 0.1. to 9.0 parts by weight of carbon black coupling agent I-V, 0.1 to 3.0 parts by weight of vulcanizing agents; 50-60 parts by weight of carbon black, 0.1 to 4.0 parts by weight of antidegradant and other additives required for rubber compounding.

DESCRIPTION OF THE INVENTION
The present invention describes a Rubber composition comprising of a diene elastomer; a vulcanization agent, an anti-degradant agent; reinforcing filler such as carbon black alone or in combination with other filler, and coupling agents with bifunctional motifs [A] such as amino- and mercapto-functionality to enhance the dispersing properties of carbon black due to the interaction of amino functionality with functional group present on carbon black and sulfide linkage with diene system and thereby enhance the rubber compounding process.
The present invention describes a process for making a carbon-reinforced rubber composition for Rubber article manufacturing specially in Tires, which provides efficient mixing of carbon black in diene rubber by incorporation of a carbon black coupling agent of the formula I-V alone or in combination thereof in the non-productive stage of mixing (master batch) in an internal mixer or two-roll mill. Subsequently, the productive stage of mixing a rubber composition comprising sulfur, a vulcanization accelerator, and antioxidants in the final vulcanization of said rubber composition.
Mercapto-amino-dual functionalized carbon black coupling agents (compounds) are represented by the formula I-V, Compounds I-V are primarily bifunctional molecules having an affinity towards both carbon black and diene rubber, in which amino-functionality has an affinity towards carbon black (CB) and interacts with oxygenic groups of carbon black (carboxyl, ester, etc), whereas mercapto functionality has an affinity towards rubber, resulting in efficient mixing of carbon black in rubber matrix and hence function as a coupling agent for carbon black. Moreover, these molecules participate in the vulcanization process due to sulfur -sulfur bond breaking of carbon black coupling agents to form respective radical and are found to reduce the viscosity of the compounding material due to better dispersion of carbon black filler in rubber and help in processing in subsequent mixing stages, and finally provide reduced rolling resistance and heat build-up towards fuel savings.

Structure I, describes ortho- 2,2'-Dianilino disulfide (o-DADS), & para- 4,4'-Dianilino disulfide (p-DADS);
Structure II, describes polysulfide of o-DADS (i.e., o-DAPS) & p-DADS (i.e., p-DAPS);
Structure III, describes the condensation products of o-DADS and p-DADS with carboxylic acid/ ester/ anhydride e.g. IIIa (o-DADS -maleic anhydride condensation product);
Structure IV, describes metal salts of compounds III [R1: aliphatic saturated/ unsaturated chain with a functional group which can interact with the functional group present on carbon black, Carbon chain length C4-C20, M is metal salt Na, K];
Structure V, describe salts of o-DADS & p-DADS with aliphatic/aromatic carboxylic acid contains C4-C20 saturated/ unsaturated carbon chain.
These compounds I-V can be prepared by synthetic methods that are known to a person skilled in the art.
2,2'-Dianilino disulfide (referred to as o-DADS) is prepared from Benzothiazole hydrolysis by caustic under reflux, followed by cooling and solvent extraction to remove unreacted benzothiazole & other impurities and then oxidized by H2O2-Acid in good yield as solid yellow material having melting point 91- 93oC. This product can also be synthesized from ortho-Chloronitrobenzene (ONCB) by reacting with sodium sulfide, followed by removal of by-products and then oxidation with a suitable oxidizing agent. Similarly, the para-isomer (p-DADS) process is from para-chloronitrobenzene by reacting with sodium sulphide, followed by oxidation with oxidizing agent.
Compounds II are the polysulfide of 2,2'-Dianilino disulfide (o-DADS) and 4,4’-Dianilino disulfides (p-DADS) obtained from sulfur insertion methods.
Compounds III can easily be prepared by dissolving compounds 2,2'-Dianilino/ 4,4’-Dianilino disulfides (ortho/ para) in a solvent and reaction with two equivalents of anhydrides/ carboxylic acid/acid chloride/ esters in good yield.
The compound of formula IV is the alkali salts of compound formula III which can be obtained by reaction with alkali salts at moderate temperature in desired solvents.
Compounds of formula V are the salts of 2,2'-Dianilino/ 4,4’-Dianilino disulfides (ortho/para) with carboxylic acid obtained by simply mixing 2,2'-Dianilino/4,4’-Dianilino disulfides and carboxylic acid at elevated temperature.
According to an embodiment of the present invention, the coupling agents for carbon black and the rubber mixture obtained in the first non-productive mixing step comprise 100 parts by weight of the diene rubber, 50-60 parts of carbon black, and 0.1 to 9 parts of Mercapto-amino-functionalized carbon black coupling agents I-V.
According to another embodiment, coupling agents are mixed in the non-productive stage as such or on carriers such as carbon black, and or silica.
According to another embodiment of the present invention, the coupling agents for carbon black and the rubber mixture obtained in the first non-productive mixing step comprise preferably 1-2 parts by weight per 100 parts by weight of rubber component and other agents which are used in the processing.
The diene rubber that is used in the present invention process can be selected from natural rubber (NR), synthetic rubber such as isoprene rubber, butadiene rubber (BR), styrene-butadiene rubber (SBR) alone, or a mixture thereof. In the case of a mixture, the blend contains more than 20- 80 parts by weight of the natural rubber per 100 parts by weight of the total rubber blend, preferably 50-60 parts by weight of the natural rubber per 100 parts by weight of total rubber.
Various types of Carbon black (CB) having varying particle sizes and morphology are used in Tire for different purpose namely CB type of fine particle size (< 20 Micron) are used for Treads, slightly coarser particle sizes (< 30 Micron) are used for Belt and relatively larger particle size (< 50 Micron) are used for sidewalls and other tire components. Examples of such carbon black include various grades of N110, N121, N210, N220, N234, N231, N299, N326, N330, N339, N347, N351, N358, N375, N550, N539, N650, N660, N762, N765, N774 in ASTM numbers.
In accordance with the present invention, a sulfur vulcanizable rubber composition typically contains 20 to 80 parts of carbon black by weight per 100 parts by weight of the rubber component, more preferably 50 to 60 parts by weight of carbon black.
In the present invention, the amount of sulfur (normal and/or Insoluble sulfur), any other type of polymeric sulfur or sulfur donor or a mixture thereof, and/ or Polymer bound sulfur is employed is 0.1 to 3 phr or more preferably 1.0 – 2 0 phr by weight per 100 parts by weight of rubber component.
In the present invention, either a single vulcanization accelerator or a mixture of accelerators can be employed in an amount of 0.1 – 3 parts per weight, more preferably 0.5 -1.5 parts per weight per 100 parts by weight of rubber component.
Typical vulcanization accelerators include thiazole- and benzothiazole-based accelerators for example 2-Mercaptobenzothiazole, bis-(2-benzothiazolyl) disulphide, benzothiazole-2-sulphenamide based accelerators such as N-Cyclohexyl-benzothiazole-2-sulphenamide (CBS), N-tert-butyl-benzothiazole-2-sulphenamide (TBBS), N, N’-dicyclohexyl-benzothiazole-2-sulphenamide (DCBS) and 2-(Morpholinothio)benzothiazole (MOR), N-t-butyl-2-benzothiazole sulfenamide (TBSI), and other conventional thiurams, dithiocarbamates etc. Preferably, the vulcanization accelerator comprises an N-Cyclohexyl-benzothiazole-2-sulphenamide (CBS) and N-tert-butyl-benzothiazole-2-sulphenamide (TBBS).
In the present invention, conventional rubber additives may also be included in the vulcanizable rubber composition for examples processing oils, tackifiers, waxes, antioxidants (phenolic or TMQ), antidegradants (phenylenediamine based), resins, plasticizers, and vulcanization activators, such as stearic acid and zinc oxide as per requirement.
According to another aspect of the invention, the coupling agent of the present invention is added in the non-productive stage (master batch) of mixing and reduces the mixing stages and time. In Practice, any rubber compound is mixed as a non-productive stage and a productive stage. Non-productive stage involves a number of re-passes (mixing stages) to achieve the desired Mooney Viscosity for processing, while the productive stage involves the addition of sulfur and accelerator which cannot be re-passed.
Re-pass/ remixing stages are required to achieve the desired Mooney Viscosity during manufacturing rubber goods (it involves a minimum of three mixing stages, according to the present invention one stage can be eliminated at the manufacturing level).
The vulcanization process of the present invention involves preparing a masterbatch comprising of rubber, carbon black, activators, anti-degradant, a processing oil, and the carbon black coupling agent in an internal mixer such as Banbury mixer, Kneeder, intermix i.e., the non-productive stage of mixing and later adding a vulcanization system comprising of sulfur, and vulcanization accelerators to the masterbatch in internal mixer such as Banbury, Two-roll mill in the productive stage of mixing. After mixing, the uncured rubber composition is matured for 24 hrs, followed by vulcanization by heating at 140 -1800C for 6 hours, more preferably for 3 hours, e.g., by compression moulding, transfer moulding, and injection moulding. The present invention relates to articles of manufacture, such as pneumatic tires, e.g., Not limited to passenger cars and trucks but applicable to all types of tire, and industrial rubber goods which comprise the rubber vulcanizate obtained by the invention process.
In the present invention, rubber compounding is performed by known methods for rubber compounding, except for the addition of novel coupling agents in master batch for coupling carbon black and improving the dispersibility of very fine carbon black particles. A master batch of rubber, carbon black, stearic acid, zinc oxide, processing oil, antidegradant and carbon black coupling agent mixed in an internal mixer (Banbury, dump temperature 140-1600 C). Subsequently, sulfur, an accelerator were mixed with the masterbatch on a two-roll mill at 50 -700 C and matured for 24 hours. Rubber compounds were vulcanized by compression moulding at 1400C for a period of time equal to the optimum cure time (t90- Rheometer graph). After cooling the vulcanized sheets were kept for 24 hours. Test specimens were cut, and their properties were determined as per ASTM standard methods.
The rheological properties were determined on a Monsanto Rheometer MDR 2000 as per ASTM D 5289, Scorch time (ts2) is the time to increase the torque 2 dNm above the minimum torque (MH). Tend is the time at the rheometer and is set at 1 hour (Delta S) is the difference between the minimum and the maximum torque. The slope of a rheograph between ML and MH is a measure of the cure rate (RH). Hysteresis is the percentage of energy lost per cycle of deformation. The ratio of loss modulus to storage modulus is defined as mechanical loss and this corresponds to Tangent delta (tan delta).
Heat build-up (HBU) measurements i.e., determination of the needle temperature, were carried out in accordance with ASTM D623/A.
In the present invention, the carbon dispersion study (Payne effect) is determined by ASTM D8059 Method on the uncured samples from each carbon black compound through measurement of shear storage modules at low & high strains. The Rubber Processor Analyzer (RPA) of Alpha technologies is used for this study and the dynamic mechanical properties were determined. Goodrich heat built-up study is conducted on Goodrich Flexometer ASTM D 623 method. The carbon black dispersion in the rubber matrix is observed by AlphaView Dispergrader of Alpha Technologies- ASTM D7723 method.

Examples
The present invention is described by the following examples, but the invention is not limited to those examples only.

Example 1: Carbon Black Coupling agents [I-V].
2,2'-Dianilino disulfide (o-DADS) Ia, synthesized from benzothiazole (1.0 mole) in alkaline hydrolysis (NaOH 2.0 mole) at 100-120 oC for 4 hours & further oxidations using 30% hydrogen-peroxide acid mixture (1.42 mole) at 20-30 oC for 1-2 hours. Unreacted benzothiazole is recovered by toluene extraction & oxidation of sodium salt of ortho-amino-thiophenol present in an aqueous layer using H2SO4-hydrogen peroxide to obtain yellow color crystalline o-DADS (Ia) in good yield (> 95%) having Melting point 90-92 oC & HPLC purity > 98 %.
p-DADS (Ib) having Melting point 76-77 °C and HPLC purity > 98 % was prepared by reacting para-chloro nitrobenzene with sodium sulfide, followed by removal para-chloro aniline by-product and oxidation using suitable oxidizing agent.
2,2'-Dianilino polysulfides (o-DAPS) IIa, and 4,4'-Dianilino polyulfide (p-DAPS) IIb are synthesized from Ia & Ib. Reaction of o/p-DADS (1.0 mole) and sulfur (1.0 mole) at 130 oC for 2 hours results in IIa & IIb which are a mixture of di-sulfide, tri-sulfide, and tetra-sulfide and higher sulfide. The percentage of di- ~25%, tri- ~30%, and tetra- ~20 % and higher sulfides ~5 % are found by analysis.
Compound IIIa prepared from 2,2'-Dianilino disulfides (Ia) & maleic anhydride condensation reaction in solvent (ethyl acetate, THF, Acetonitrile, toluene) at elevated temperature. 2,2'-Dianilino disulfide (ortho) (1.0 mole) is dissolved in a suitable solvent, and maleic anhydride (2.0 mole) is also dissolved in the same solvent at 25-40 oC. Solution of o-DADS is added to the dissolved maleic anhydride over a period of 2 hours and the reaction mass is heated to 75-77 oC for 2 hours. Cooled the reaction mass to 30 oC to precipitate the product, which is filtered, and dried. The melting point is 205-208 oC, the yield is 96-98 %, having Purity > 98 %.
Compound IVa is prepared from IIIa. Compound IIIa (1.0 mole) is dissolved in methanol-water (50:50) solvents. Sodium carbonate solution (1.0 mole) is added to the compound IIIa solution and heated the reaction mass at 50 oC for 2 hours. After 2 hours, removed the methanol-water to dryness to obtain compound IVa in 98 % yield having > 98 % purity.
Compound Va is prepared from 2,2'-Dianilino disulfide (ortho) and stearic acid at elevated temperature. 2,2'-Dianilino disulfide (1.0 mole) and stearic acid (2.0 mole) melted separately and mixed at 92 oC. Cooled the mixture to isolate the yellow color salt in solid form.

Table 1: Representative Carbon Black Coupling Agents
Abbreviation Compounds Structure

o-DADS
(Ia)

p-DADS
(Ib)

o-DAPS
(IIa)

p-DAPS
(IIb)

o-DADS-MAA
(IIIa)

[o-DADS – Maleic anhydride condensation product]

p-DADS-MAA
(IIIb)
[p-DADS -Maleic anhydride condensation product]
o-DADS-MAAS
(IVa)

[Sodium salt of o-DADS– Maleic anhydride condensation product]
M: Na
p-DADS-MAAS
(IVb)

[Sodium salt of p-DADS–Maleic anhydride condensation product]
M: Na

o-DADS-SA
(Va)

[o-DADS– stearic acid salt]

p-DADS-SA
(Vb)

[p-DADS– stearic acid salt]

Example 2
The mixing sequence of rubber compounding of 100 parts by weight of the total rubber is conducted in Banbury as per Table 2 and formulation as per Table 3. Non-productive mixing of the compounds was done in laboratory scale Banbury mixture of 1.5 Lit Capacity. The temperature control unit was set as 140-150 oC during non-productive mixing and productive mixing at 50-70 oC on the lab two-roll mill. ASTM Standards were followed for conducting the tests: Mooney Viscosity, Mooney Scorch, Rheometer, and Tensile Properties on the compound as shown in Table-3.

Table 2: Mixing Sequence of Compounds followed in Banbury and two-roll mill.
Time (s) Actions
Non-productive stage
0.0 Loading a raw rubber (NR or synthetic rubber alone or mixture) at 50 rpm at 65-70oC Chamber temperature.
0.5 Addition of zinc oxide at 75 ± 5oC.
1.0 Addition of half the quantity of carbon black & carbon black coupling agent at 100 ± 5oC.
3.0 Addition of stearic acid + half the quantity of carbon black + Elasto 245 + 6PPD + TMQ at 125 ± 5oC.
4.5 Sweep the blend at 145 ± 5oC.
4.6 Dump the master batch at 140oC and time 6 minutes.
Productive stage Lab Two Roll Mill mixing
Heat the mill roll to 50-70oC.
Addition of non-productive compound on the mill roll and allow it to band on the front roll.
8.0-10.0 Addition of sulfur + accelerator on the two-roll mill and allow it to incorporate.

Table 3: Formulation based on natural and synthetic rubber.
Ingredients Control Compounds Test Sample
Master I
Natural Rubber 100.00 100.00
Carbon Black (CB) 55.00 55.00
Carbon Black Coupling Agent - 1.00
Zinc Oxide 5:00 5:00
Stearic acid 2:00 2:00
Elasto 245 5:00 5:00
6-PPD 2:00 2:00
TMQ 1:00 1:00
Final
Sulfur 2:00 2:00
Accelerator –CBS 0.7 0.7
PVI 0.20 0.20

6PPD: N-phenyl-N’-(1,3-dimethylbutyl)-p-phenylene diamine;
TMQ: 2,2,4-Trimethyl-1,2-dihydroquinoline; Elasto 245: Rubber process oil.
CBS: N-Cyclohexyl-2-benzothiazole sulfenamide.
PVI: N-(cyclohexylthio) phthalimide.
Quantities are in parts by weight per 100 parts by weight of the rubber component.

Example 3:
Compounds o-DADS (Ia), o-DAPS (IIa) o-DADS-MAA (IIIa), and o-DADS-MAAS (IVa) are studied for carbon dispersion and other properties in carbon black HAF N330 in natural rubber (Table 4). The rubber mixture obtained in the first step comprises 100 parts by weight of the diene rubber component, Sulfur (2 parts by weight), Zinc Oxide (5 parts by weight), Stearic acid (2 part by weight), 6-PPD (2 part by weight), TMQ (1 part by weight), CBS (0.7 parts by weight), PVI (0.20 parts by weight), Carbon black HAF N330 (55 parts by weight), Elasto 245 ( 5 parts by weight) and carbon black coupling agent (1 part by weight).

Table 4: Rubber Compounding Details: Control, o-DADS, o-DAPS, o-DADS MAA, and o-DADS-MAAS in natural rubber
Base Recipe Control o-DADS
(Ia) o-DAPS
(IIa) o-DADS-MAA
(IIIa) o-DADS-MAAS (IVa)
NR 100.00 100.00 100.00 100.00 100.00
Zinc Oxide 5.00 5.00 5.00 5.00 5.00
Stearic Acid 2.00 2.00 2.00 2.00 2.00
6-PPD 2.00 2.00 2.00 2.00 2.00
TMQ 1.00 1.00 1.00 1.00 1.00
HAF N 330 55.00 55.00 55.00 55.00 55.00
o-DADS -- 1.00
o-DAPS 1.00
o-DADS-MAA 1.00
o-DADS-MAAS 1.00
Elasto 245 5.00 5.00 5.00 5.00 5.00
Mater Total 170.00 171.00 171.00 171.00 171.00
Sulphur 2.00 2.00 2.00 2.00 2.00
CBS 0.70 0.70 0.70 0.70 0.70
PVI 0.20 0.20 0.20 0.20 0.20
Total 172.90 173.90 173.90 173.90 173.90

Mooney Viscosity and Rheological properties of Control, o-DADS, o-DAPS, o-DADS-MAA, and o-DADS-MAAS
Compound Code: Control o-DADS o-DAPS o-DADS MAA o-DADS MAAS
Mooney Viscosity: (ML1+4) - ASTM D 1646: Temp- 100 °C
Productive Compound 74.31 53.91 56.00 70.00 70.88
Rheometric Test: MDR (ASTM D 5289), Arc 0.5°, Temp.140 °C
Delta Torque, dN-m 15.23 16.38 17.72 15.47 15.84
Optimum Cure Time, tc 90 minutes 20.18 22.77 22.19 24.37 29.64

In the present invention, with respect to control, all the carbon coupling agents of the present invention showed a lowering of Mooney viscosity, resulting in better filler-rubber mixing & carbon dispersion; however, lowering of viscosity is relatively more for o-DADS (Ia) and o-DAPS (IIa) in comparison to o-DADS-MAA (IIIa) & o-DADS-MAAS (IVa). As per the present invention, carbon black coupling agents containing bi-functional groups, and amino/ carboxylic acid functional groups interact with the functional groups present on carbon black, which helps in the dispersion of carbon black in rubber by reducing filler-filler interactions. Sulfide linkage is another functional group that participates in the curing (i.e. interaction with the diene system).
Stress-strain properties of rubber composite evaluated at room temperature for o-DADS (Ia), o-DAPS (IIa), o-DADS MAA (IIIa) & o-DADS MAAS (IVa) are summarized in the following Table 5.

Table 5: Stress-Strain properties of rubber composite
Unaged Stress-Strain Properties (ASTM D 412), Cure; 140 °C, Optimum Cure Time
Control o-DADS o-DAPS o-DADS MAA o-DADS MAAS
Modulus 300%, Mpa 15.25 13.43 14.0 14.23 16.8
Tensile Strength, Mpa 27.3 25.15 26.0 26.6 27.0
Elongation at Break, % 490 505 500 515 495
Hardness Shore A 65 65 65 65 65
Compounds o-DADS (Ia), o-DAPS (IIa), o-DADS MAA (IIIa) & o-DADS MAAS (IVa) have shown comparable properties at 300 % modulus (within accepted range) compared to control. Considering the above processing parameters and physical properties all these compounds are suitable for mixing cycle reduction with improved processibility.
One of the key features of carbon black coupling agents is to improve the dispersion of carbon black in the rubber matrix by reducing filler-filler interaction, i.e. less agglomeration. The improved dispersibility of hard (finer) carbon-N330 in natural rubber is confirmed on Alpha View Dispergrader for o-DADS (Ia), o-DADS-MAA (IIIa), and o-DADS-MAAS (IVa) and in all the cases carbon black dispersion have improved with respect to control. The dispersion results are summarized in Table 6. In the present invention, coupling agents helped in improving the dispersibility of carbon black in the rubber matrix.
Table 6: Dispersion of carbon Black N330 in Natural rubber in the presence of coupling agents o-DADS (Ia), o-DADS-MAA (IIIa), and o-DADS-MAAS (IVa) [X= 10 being perfectly dispersed and X= 1 being poorly dispersed], wherein the images have been set out in Figure 1.
Compounds X (Rating) Dispersion %
NR + Carbon Black (Control) 6.2 89.3
Natural Rubber + Carbon Black + o-DADS 9.0 99.3
Natural Rubber + Carbon Black + o-DADS-MAA 6.8 92.4
Natural Rubber + Carbon Black + o-DADS-MAAS 7.9 97.7

Example 4
The present invention applies to each component of the tire, such as the thread part, under the thread, casing, side wall part, bead part, and belt- textile/steel reinforced components. Examples of Carbon black includes various grades of N110, N121, N210, N220, N234, N231, N299, N326, N330, N339, N347, N351, N358, N375, N550, N539, N650, N660, N762, N765, N774 in ASTM numbers. The sequence and formulations of rubber compounding are as per Table 2 and Table 3. The amount of the carbon black blended is about 20 to 80 parts, preferably 50 - 60 parts by weight, more preferably 55 per 100 parts by weight of the rubber components. The carbon black of various grades of different particle sizes in natural and synthetic rubber is used for the dispersion & other properties study. 1.0 part by weight of carbon black coupling agents are used for this study. The test compounds are selected from the ortho series of DADS i.e. o-DADS. The carbon black used for this study are preferably N 220, N 330, N234, N339, N 550, N660, and N774. Formulation details and Rheological properties are summarised in the following Tables 7 and 8.

Table 7: Hard (Finer particle size) Carbon black dispersion study in natural rubber in the presence of o-DADS: Rubber Compounding Details
Base Recipe N 330 N 330 + o-DADS N 339 N 339 + o-DADS N 220 N 220 + o-DADS N 234 N 234 + o-DADS
NR 100.00 100.00 100.00 100.00 100.00 100.00 100.00 100.00
Zinc Oxide 5.00 5.00 5.00 5.00 5.00 5.00 5.00 5.00
Stearic Acid 2.00 2.00 2.00 2.00 2.00 2.00 2.00 2.00
6-PPD 2.00 2.00 2.00 2.00 2.00 2.00 2.00 2.00
TMQ 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00
HAF N 330 55.00 55.00 - - - - - -
HAF N 339 - - 55.00 55.00 - - - -
ISAF N 220 - - - - 55.00 55.00 - -
ISAF N 234 - - - - - - 55.00 55.00
o-DADS - 1.00 - 1.00 - 1.00 - 1.00
Elasto 245 5.00 5.00 5.00 5.00 5.00 5.00 5.00 5.00
Master Total 170.00 171.00 170.00 171.00 170.00 171.00 170.00 171.00
Sulphur 2.00 2.00 2.00 2.00 2.00 2.00 2.00 2.00
CBS 0.70 0.70 0.70 0.70 0.70 0.70 0.70 0.70
PVI 0.20 0.20 0.20 0.20 0.20 0.20 0.20 0.20
Total 172.90 173.90 172.90 173.90 172.90 173.90 172.90 173.90

Table 8. Physical, Rheological, and Dynamic Properties of rubber compounding the in presence of o-DADS carbon black coupling agents.
Properties N 330 N 330 +
o-DADS N 339 N 339 +
o-DADS N 220 N 220 +
o-DADS N 234 N 234 +
o-DADS
Mooney Viscosity (ASTM D 1646): Temp- 100°C
Mooney Viscosity ML (1+4) - Master 108 85 117 90 135 119 145 111
Mooney Viscosity ML (1+4) – Final 77 65 83 70 92 90 108 83
Rheometric Test: MDR (ASTM D 5289), Arc:0.5o, Temp:140 °C
Maximum Torque, dN-m, 19.99 20.26 19.74 20.46 20.67 22.26 22.07 22.23
(Max - Mini) Torque, dN-m, 16.27 16.90 15.75 16.89 16.12 17.44 17.03 17.86
Scorch Time, ts2, minute 8.62 6.70 8.37 6.64 8.42 7.26 7.42 5.83
Optimum Cure Time, Tc 90, minute 19.71 18.27 19.38 18.74 20.40 21.3 18.80 21.14
Unaged Stress–Strain Properties (ASTM D 412), Cure: 140 °C, Optimum Cure Time (OCT)
300% Modulus, Mpa 17.5 16.0 17.5 16.5 17.0 16.0 19.5 17.0
Tensile Strength, Mpa 28.0 27.0 28.0 27.5 28.5 29.0 29.5 28.0
Elongation at Break, % 445 490 445 460 455 490 430 455
Hardness Shore A 68 68 68 69 69 69 69 69

Carbon black of various grades is used in the present study, 1.0 part by weight of coupling agents to 100 parts by rubber components is used for compounding. The carbon coupling agent is used in the master batch (non-productive stage). Reduction in master compound viscosity is observed for studied carbon black indicating no repass step is required to reduce the viscosity of the compound for further processing. Reduction in both mixing and processing time will help in the improvement in energy efficiency. A carbon black with finer particle size showed a 20-30 % viscosity reduction in the presence of o-DADS in comparison to without the carbon black coupling agent, Coarser carbon black showed 10-15 % drop in Mooney viscosity in the presence of o-DADS. Improvement in Elongation at Break, % is observed in the presence of carbon black coupling agent (o-DADS). An increase in cross-link density in the range of 10-15 % is observed for carbon black with o-DADS, this indicates strong polymer-filler interaction due to the presence of Carbon Black Coupling agents.
Heat built-up is the critical factor for carbon black-rubber compounding, in the present invention. Heat build-up study is conducted for different hard grades carbon black (fine/coarse) in the presence of carbon black coupling agent (o-DADS) summarised in the invention (Table 9). For Studied carbon black, a reduction in heat built-up is observed for all carbon black. This confirms less filler-filler interaction of carbon black and better dispersion in rubber matrix.

Table 9: Good-rich heat built-up properties, Payne Effect & Dynamic Properties of carbon black dispersed rubber in the presence of carbon black coupling agent (o-DADS).

Properties N 330 N 330
+ o-DADS N 339 N 339
+ o-DADS N 220 N 220
+ o-DADS N 234 N 234
+ o-DADS
Goodrich Flexometer: ASTM D 623 – 07, Cure: 140 °C / OCT + 5 minutes
Delta T °c 8.5 8.0 8.5 7.0 9.5 8.5 10.0 7.5
RPA Data: ASTM 8059, Condition: Frequency: 1 Hz, Temp.: 70, Conditioning Time: 10 mins.
Payne Effect: 1562 1367 1530 1446 2115 1827 2552 2517
RPA Dynamic Strain: Cure: 140 ?C, 30 mins, Frequency: 10 Hz. Temperature: 60°C
tan-? @1.0 %, Temp. 60°c
0.094 0.089 0.093 0.091 0.106 0.101 0.105 0.087

In the present invention, the Payne effect (Relatively lower value shows better carbon dispersion) and cure dynamic properties for different grades of carbon black dispersed in natural rubber are evaluated. Reduction of Payne effect indicates better rubber-filler interaction & dispersion.
As summarised in the Table 9, the decrease in the Payne effect for test compounds in the presence of carbon black coupling agent confirms less aggregation tendency of carbon black in the presence of o-DADS carbon black coupling agent. This result proves that filler-rubber interaction improves in the presence of o-DADS and strongly support the current invention of Carbon coupling agents for better dispersion of carbon black in rubber and reduction in carbon black filler-filler interaction. Dynamic mechanical properties of the compounds were evaluated for test compounds at 60oC and compared with the control sample. As summarised in the following Table 9, slight reduction in the tan delta without affecting the modulus is an indication of a reduction of rolling resistance properties in the tire.
Like hard carbon grades, physical, rheological, dynamic, and other properties are evaluated in soft-grade (coarser particle size) carbon. Table 10 represents the details of rubber compounding and Table 11 is the properties of compounded rubber in the presence of a carbon black coupling agent.

Table 10: Soft Grade Carbon Black Dispersion Study in Natural Rubber in the Presence of Carbon Black Coupling Agent: Rubber Compounding Details
Base Recipe N 774 N 774 + o-DADS N 660 N 660 + o-DADS N 550 N 550 + o-DADS
NR 100.00 100.00 100.00 100.00 100.00 100.00
Zinc Oxide 5.00 5.00 5.00 5.00 5.00 5.00
Stearic Acid 2.00 2.00 2.00 2.00 2.00 2.00
6-PPD 2.00 2.00 2.00 2.00 2.00 2.00
TMQ 1.00 1.00 1.00 1.00 1.00 1.00
HAF N 774 55.00 55.00 - - - -
HAF N 660 - - 55.00 55.00 - -
ISAF N 550 - - - - 55.00 55.00
o-DADS - 1.00 - 1.00 - 1.00
Elasto 245 5.00 5.00 5.00 5.00 5.00 5.00
Master Total 170.00 171.00 170.00 171.00 170.00 171.00
Sulfur 2.00 2.00 2.00 2.00 2.00 2.00
CBS 0.70 0.70 0.70 0.70 0.70 0.70
PVI 0.20 0.20 0.20 0.20 0.20 0.20
Total 172.90 173.90 172.90 173.90 172.90 173.90

Table 11: Physical, Rheological, and Dynamic Properties of rubber compounding the in presence of o-DADS carbon black coupling agents in soft Grade Carbon Black
Compound Code N774 N774 +
o-DADS N660 N660 + o-DADS N550 N550 + o-DADS
Mooney Viscosity: (ML1+4) - ASTM D 1646: Temp- 100 °C
Productive Compound 47.6 36.5 55.2 39.2 57.4 48.4
Rheometric Test: MDR (ASTM D 5289), Arc 0.5°, Temp.140 °C
Delta Torque, dN-m 12.59 13.42 13.45 13.76 14.45 14.83
Scorch Time, ts2, minutes 11.34 10.20 13.05 10.86 10.65 9.37
Optimum Cure Time, tc 90 minutes 22.30 23.73 24.12 24.46 21.73 23.25
Unaged Stress-Strain Properties (ASTM D 412), Cure; 140 °C, Optimum cure time (OCT)
Modulus 300%, Mpa 11.2 9.30 13.0 9.55 15.0 12.0
Tensile Strength, Mpa 24.8 22.0 24.0 21.5 24.8 22.0
Elongation at Break, % 545 550 505 550 490 515
Hardness Shore A 61 57 62 58 66 61

Example 5
In the present invention, diene rubber used as a rubber component includes natural rubber, synthetic rubber alone, or a mixture thereof. Styrene-butadiene rubber (SBR), butadiene rubber (BR), polybutadiene (PBR) alone, or a mixture of NR-SBR-BR used in the present invention. The rubber compounding is as per Table 2 and Table 3. The diene system used for compounding is 100 parts by weight of the total of natural rubber or synthetic rubber. In the case of a mixture, 20-80 parts by weight of natural rubber to the 100 parts rubber components used, preferably 60-80 parts by weight of natural rubber to the total 100 parts of rubber components. Synthetic rubber used in the invention is 20-40 parts by weight to the 100 parts of rubber components, preferably 20-40 parts by weight. The composition of rubber compounding & obtained properties is summarised in Tables 12 & 13. In natural rubber, o-DADS showed an increase in torque while in the blend (NR+SBR/BR) the torque has been maintained and this will retain the elastic properties of compounds that are required for rubber compounds.

Table 12: Rubber Compounding of NR and mixture of natural - synthetic rubber in the presence of carbon black coupling agents
Base Recipe NR-BR NR-BR- o-DADS NR-SBR NR-SBR- o-DADS
NR 70.00 70.00 80.00 80.00
SBR 1502 20.00 20.00
BR 30.00 30.00
Zinc Oxide 5.00 5.00 5.00 5.00
Stearic Acid 2.00 2.00 2.00 2.00
6-PPD 2.00 2.00 2.00 2.00
TMQ 1.00 1.00 1.00 1.00
N 234 55.00 55.00 55.00 55.00
o-DADS 1.00 1.00
Elasto 245 10.00 10.00 10.00 10.00
Master Total 175.00 176.00 175.00 176.00
CBS 0.80 0.80 0.80 0.80
Sulphur 2.00 2.00 2.00 2.00
PVI 0.10 0.10 0.10 0.10
Total 177.90 178.90 177.90 178.90

Table 13: Physical, Rheological, and Dynamic Properties of compounded rubbers in the presence of Carbon Black Coupling agents o -DADS in natural and mixture of natural-synthetic rubber
Compound ID: NR-BR NR-BR- o-DADS NR-SBR NR-SBR- o-DADS
Mooney Viscosity (ASTM D 1646): Temp- 100 0 C - Master Batch
ML (1+4) - Master 98 73 103 69
ML (1+4) - Final 79 62 78 58
Rheometric Test: MDR (ASTM D 5289), Arc 0.5o, Temp-140 °C
Minimum Torque, dN-m, 4.15 3.57 4.04 3.26
Maximum Torque, dN-m, 22.24 21.91 21.77 21.24
(Max - Mini) Torque, dN-m, 18.09 18.34 17.73 17.98
Scorch Time, ts2, minute 11.55 8.50 12.50 8.78
Optimum Cure Time, Tc 90, minute 24.67 21.94 28.49 24.47
Unaged Stress-Strain Properties (ASTM D 412), Cure: 140°C / OCT minute
300% Modulus, Mpa 16.0 14.5 17.5 15.5
Tensile Strength, Mpa 26.0 25.0 26.5 25.5
Elongation at Break, % 440 450 425 455
Hardness Shore A 68 68 68 68
Goodrich Flexometer: ASTM D 623 - 07
Delta T °C 12.0 11.0 11.5 10.2
RPA Payne Effect: ASTM 8059, Condition: Frequency: 1 Hz, Temp.: 70, Conditioning Time: 10 mins.
Payne Effect: 2437 1499 2186 1526
RPA Dynamic Strain: Cure:140 ?C, 30 mins, Frequency: 10 Hz.
tan ? @10 %, at 60 ?C
0.136 0.126 0.171 0.156

Data presented in Table 13 is an indication of the dispersion of carbon black in natural rubber and a mixture of natural rubber & synthetic rubber. A decrease in Mooney viscosity in the presence of o-DADS is an indication of reducing the mixing steps to achieve the processing viscosity. Scorch safety, modulus, and elongation break are comparable polymer blends.

Example 6
In the present invention, the dispersion of carbon black (N330) in the presence of carbon black coupling agent and different diene systems is also evaluated Table 14. Natural rubber, butadiene rubber, styrene-butadiene rubber (SBR) used alone or a mixture thereof. Improved dispersion of carbon black is observed in the presence of the coupling agents in comparison with the control compound. The coupling agent o-DADS showed 99.3 % dispersion which is the maximum in natural rubber compounds. Dispersion properties are evaluated as the agglomeration effect of carbon black filler. In the present invention coupling agent helped in the dispersion of carbon black in the rubber system which resulted in less agglomeration.

Table 14: Dispersion of Carbon Black N330 in natural & natural-synthetic rubber in the presence of carbon black coupling agent o-DADS (Ia) and measured by dispergrader wherein the images have been set out in Figure 2.
Compounds X (Rating) Dispersion %
Natural Rubber+ Carbon Black (Control) 6.2 89.3
Natural Rubber+ Carbon Black+
o –DADS 9.0 99.3
Natural Rubber + Butadiene Rubber +
Carbon Black (Control) 7.5 95.0
Natural Rubber + Butadiene Rubber +
Carbon Black + o-DADS 8.4 98.5
Natural Rubber + Styrene Butadiene Rubber +
Carbon Black (Control) 7.0 93.5
Natural Rubber + Styrene Butadiene Rubber +
Carbon Black +o-DADS 7.1 94.3

Description of Figures
Figure 1: Images for Dispersion of carbon Black N330 in Natural rubber in the presence of coupling agents o-DADS (Ia), o-DADS-MAA (IIIa), and o-DADS-MAAS (IVa).
Figure 2: Images for Dispersion of Carbon Black N330 in natural & natural-synthetic rubber in the presence of carbon black coupling agent o-DADS (Ia)
As summarized in Examples 1 -6 of the present invention, carbon black coupling agents presented in the present inventions [A] improve the elongation at break property, reduce heat build-up, and reduce the total mixing time. Compounds also help in carbon black dispersion in the diene system by reducing filler-filler interactions. The presence of carbon black coupling agents reduces the Mooney viscosity, reduction in visco-elastic energy dissipation, and heat built-up. These improved properties can reduce rolling resistance due to filler-rubber dispersion which is expected to reduce fuel consumption and improve the durability, and safety performance of a tire. The present invention indicates scope to reduce mixing stages and help in the reduction of energy consumption during the processing cycles, and hence better manufacturing sustainability.
,CLAIMS:
1. A Rubber composition comprising a diene elastomer; a vulcanization agent, an anti-degradant agent; reinforcing filler such as carbon black alone or in combination with other filler and coupling agent, wherein the coupling agent comprises a compound of formula (A)

wherein,
n is 2, 3 4 i.e. Sulfide linkage is di-, tri- or tetra- alone or a mixture thereof;
R1 and R2 independently represent are -H, Alkyl chain of C1-C20 carbon chain which is substituted with alkyl or carboxylic acid or esters or -OH or anhydride or alkali salt or reactive functional group and the
NR1, R2 are position at ortho or para position with respect to sulfide chain.

2. The Rubber composition as claimed in claim 1, wherein the filler is in a proportion of from 50 to 60 parts by weight to 100 parts by weight of a diene rubber and the coupling agent for carbon black filler is in a proportion of from 0.1 to 9.0 parts by weight to 100 parts by weight of diene elastomer.

3. The Rubber composition as claimed in claim 1, wherein the coupling agent for enhancing dispersing properties of filler used in rubber composition, is selected from compounds having the structures:

Compounds Structure

M: Na

M: Na

4. The rubber composition as claimed in claim 1 wherein the reinforcing filler is selected from the group consisting of carbon black, silica, clay, or a combination thereof.

5. The reinforcing filler as claimed in claim 4, wherein the reinforcing filler is carbon black having particle sizes varying from 10 microns to 60 microns, preferably in between 20 to 45-micron size.

6. The rubber composition as claimed in claim 1 wherein the amount of vulcanization agent, antidegradants, per 100 parts by weight of the diene rubber components are: 0.1 to 3.0 parts by weight of sulfur or insoluble sulfur or polymeric sulfur or/ and combination thereof; 0.1 to 3.0 parts by weight of vulcanizing agent; 0.1 to 4.0 parts by weight of antidegradant system; respectively and other additives required for rubber compounding.

7. The carbon black coupling agents as claimed in claim 1, are mixed in the master batch as such or along with carriers such as carbon black, silica, and clay or a combination thereof.

8. Coupling agent for enhancing dispersion properties of fillers, wherein the coupling agents have the formula:

M: Na/ K

M: Na /K

9. Rubber composition as claimed in claim 1, can be applied to each component of the tire, such as the tread part, under tread, casing, side wall part, bead part, and belt-textile, and steal reinforced components and applied to non-tire rubber components.