tire

Abstract

To provide a tire comprising two rubber components cured together, which is an advanced tire with desirable rolling resistance and / or hysteresis characteristics.SOLUTION: The first rubber component comprises 85 phr to 100 phr of a hydrogenated styrene-butadiene rubber, 0 phr to 15 phr of a polybutadiene, 5 phr to 20 phr of a polyoctenamer, and 40 phr to 160 phr of a first filler. The second rubber component comprises 90 phr to 100 phr of a diene-based elastomer, and 20 phr to 160 phr of a second filler. Moreover, the present invention is directed to a rubber composition comprising a hydrogenated styrene-butadiene rubber, 5 phr to 20 phr of a polyoctenamer, and 40 phr to 160 phr of a reinforcing filler.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a tire comprising a first rubber component cured against a second rubber component, the first rubber component having a different composition than the second rubber component.The present invention further relates to a rubber composition. [Background technology]

[0002] In view of the constant demand for improving tire performance, new material combinations are constantly being evaluated and tested by tire manufacturers. For example, tensile properties and resistance to oxidative degradation can be improved by using hydrogenated styrene-butadiene rubber compared to standard diene polymers, especially in tread compounds. However, it can be recognized that co-curability can be limited with another diene compound. As a result, it can happen that a rubber component containing such hydrogenated styrene-butadiene rubber cured against at least a second rubber component containing a diene-based rubber can tear more easily from the second rubber component, thereby affecting the robustness of the cured tire. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] U.S. Patent Application Publication No. 2018201065 [Patent Document 2] US Patent Application Publication No. 2018251576 [Patent Document 3] U.S. Patent Application Publication No. 20190062539 [Patent Document 4] U.S. Patent No. 5,698,643 [Patent Document 5] U.S. Patent No. 5,451,646 [Patent Document 6] U.S. Patent No. 6,242,534 [Patent Document 7] U.S. Patent No. 6,207,757 [Patent Document 8] U.S. Patent No. 6,133,364 [Patent Document 9] U.S. Patent No. 6,372,857 [Patent Document 10] U.S. Patent No. 5,395,891 [Patent Document 11] U.S. Patent No. 6,127,488 [Patent Document 12] U.S. Patent No. 5,672,639 [Patent Document 13] U.S. Patent No. 6,608,125 [Patent Document 14] US Patent Application Publication No. 2003 / 0130535 [Non-patent literature]

[0004] [Non-Patent Document 1] Standard Methods for Analysis & Testing of Petroleum and Related Products and British Standard 2000 Parts, 2003, 62nd edition [Non-Patent Document 2] Journal of the American Chemical Society, Volume 60, Page 304 (1930) [Non-Patent Document 3] The Vanderbilt Rubber Handbook (1978), pp. 344-346 Summary of the Invention [Problem to be solved by the invention]

[0005] SUMMARY OF THE PRESENT EMBODIMENTS The present invention can have as a first object to provide an advanced tire having rubber components that are highly cured relative to one another. Another object of the present invention can be to provide an advanced tire having desirable rolling resistance and / or hysteresis characteristics.

[0006] Another object of the present invention can be to provide an advanced tire having a tread with advanced rolling resistance and / or hysteresis characteristics. Another object of the present invention can be to provide a tire having good tensile properties and / or advanced durability and wear resistance.

[0007] The invention is defined by the independent claims. Further preferred embodiments are defined by the dependent claims. [Means for solving the problem]

[0008] Thus, in a first aspect of the invention, a tire, preferably a cured tire, comprises a first rubber component and a second rubber component, the first rubber component being cured (or co-cured) against the second rubber component, where the first rubber component comprises 85 phr to 100 phr of a hydrogenated styrene-butadiene rubber, preferably a solution polymerized styrene-butadiene rubber (SSBR), 0 phr to 15 phr of a polybutadiene, 5 phr to 20 phr of a polyoctenamer, and 40 phr to 160 phr of a first filler. The second rubber component comprises 90 phr to 100 phr of a diene-based elastomer, and 20 phr to 160 phr of a second filler. The inventors have discovered that the polyoctenamer surprisingly improves the co-curability of the first rubber component comprising the hydrogenated SSBR with another diene-based rubber composition. At the same time, the level of exhibited hysteresis is reduced, indicating reduced tire rolling resistance, ultimately resulting in better vehicle fuel economy.

[0009] In one embodiment of the present invention, the first rubber component, or in other words the rubber composition of said component, comprises 95 phr to 100 phr of hydrogenated styrene-butadiene rubber, and 0 phr to 5 phr of polybutadiene. The inventors have found that lower amounts of polybutadiene are much more desirable in the preferred embodiment of the present invention. Much more preferably, the compound can comprise 100 phr of hydrogenated SSBR.

[0010] Hydrogenated SSBR and its preparation are known per se to those skilled in the art and are described, for example, in U.S. Patent Application Publication Nos. 2018201065, 2018251576 and 20190062539.

[0011] In another embodiment, the first rubber component comprises from 5 phr to 15 phr of polyoctenamer, such an amount has been found to be most desirable. In yet another embodiment, the diene based elastomer (of the second rubber component) comprises polyisoprene or polybutadiene or a combination thereof.

[0012] In yet another embodiment, the tire has a tread and the first and second components are components of the tread. Alternatively, the second rubber component may be a sidewall, the sidewall being cured relative to the tread at an axially outer portion of the tread.

[0013] In yet another embodiment, the first rubber component is a tread cap layer of the tread and the second rubber component is a second tread cap layer or a tread base layer of the tread. The first rubber component may be cured against the second rubber component essentially along a cylindrical surface extending circumferentially around the tire.

[0014] In yet another embodiment, the hydrogenated SSBR has less than 5%, preferably less than 2%, non-hydrogenated vinyl groups (vinyl groups that are not hydrogenated), based on the total number of vinyl and ethyl groups in the hydrogenated SSBR.

[0015] In yet another embodiment, the hydrogenated SSBR has less than 5%, or less than 2%, or even less than 1% of double bonds along its backbone (excluding styrene, vinyl, ethyl, and other side groups) based on the total number of bonds along its backbone. In some cases, the hydrogenated SSBR will be 60%-99% hydrogenated, 70%-99% hydrogenated, or 90%-99% hydrogenated. In another preferred embodiment, the hydrogenated styrene-butadiene rubber has 90%-98% hydrogenated double bonds. In other words, there are still unhydrogenated double bonds remaining. Generally, styrene groups or any cyclic groups shall not be counted in this case for purposes of determining the number of bonds or double bonds. As known to those skilled in the art, the number of double bonds can be determined by NMR.

[0016] In yet another embodiment, the second rubber component comprises 30 phr to 90 phr of polyisoprene, 10 phr to 70 phr of polybutadiene, and 30 phr to 70 phr of fillers, particularly carbon black and / or silica. For example, this may be the composition of the base compound of the present invention. The polyisoprene may be natural rubber or synthetic polyisoprene rubber. The polybutadiene rubber will typically be a high cis-1,4-polyisoprene rubber having at least 95% cis microstructure content.

[0017] In yet another embodiment, the first filler comprises primarily silica and / or the second filler comprises primarily carbon black. For example, the first filler may comprise 1 phr to 10 phr of carbon black and 30 phr to 159 phr of silica; and / or the second filler may comprise 15 phr to 70 phr of carbon black and 10 phr to 60 phr of silica.

[0018] In another embodiment, the first component comprises 60 to 80 phr of silica. In yet another embodiment, the polybutadiene has a glass transition temperature in the range of -90°C to -115°C, preferably -90°C to -110°C.

[0019] In yet another embodiment, the hydrogenated styrene-butadiene rubber has a glass transition temperature in the range of -20°C to -50°C. In yet another embodiment, the styrene-butadiene rubber will have a bound styrene content in the range of 10% to 40% and a bound butadiene content in the range of 60% to 90% by weight as determined by NMR. The styrene-butadiene rubber will typically have a bound styrene content in the range of 25% to 35% and a bound butadiene content in the range of 65% to 75%.

[0020] In yet another embodiment, the first rubber component comprises between 5 phr and 25 phr of oil, and 5 phr to 20 phr of a plasticizer comprising a resin, from 15 phr to 40 phr. In a preferred embodiment, the first compound comprises a resin, particularly in the range of 5 phr to 20 phr, which may optionally be a hydrocarbon resin, preferably an alpha-pinene based resin.

[0021] In yet another preferred embodiment, the resin to oil ratio is in the range of about 1:1 to 1:4 (all by phr). Even more preferably, the resin to oil ratio is in the range of about 1:1.5 to 1:3.

[0022] In another preferred embodiment, the polyoctenamer has a glass transition temperature in the range of −50° C. to −80° C., as determined below under ASTM D3418; a weight average molecular weight M between 80,000 and 100,000, as determined by gel permeation chromatography (GPC) according to ASTM 5296-11 or equivalent using polystyrene calibration standards. W and having one or more of a melting point between 45° C. and 55° C. as measured on the second heat by DSC according to ASTM D3418 or equivalent.

[0023] In yet another preferred embodiment, the polyoctenamer has between 65% and 85% trans double bonds of all double bonds in the polyoctenamer. In another preferred embodiment, the first component comprises a (first) rubber composition and the second component comprises a (second) rubber composition different from the rubber composition of the first rubber component. The first and / or second rubber composition may be a sulfur vulcanizable or sulfur vulcanized rubber composition.

[0024] In another embodiment of the present invention, there is provided a rubber composition consisting of (in other words including) hydrogenated styrene-butadiene rubber, 5 phr to 20 phr of polyoctenamer, and 40 phr to 160 phr of reinforcing filler. The rubber composition may be a rubber composition of the first rubber component.

[0025] In one embodiment, the rubber composition further comprises 5 phr to 15 phr of a high cis-polybutadiene rubber having at least 95% cis microstructure content. In another embodiment, the rubber composition further comprises 5 phr to 25 phr of oil and 5 phr to 15 phr of resin.

[0026] In yet another embodiment, the resin is an alpha pinene-based resin. In yet another embodiment, the hydrogenated styrene-butadiene rubber has one or more of: (i) less than 5% unhydrogenated vinyl groups, based on the total number of vinyl and ethyl groups of the hydrogenated styrene-butadiene rubber; (ii) less than 2% double bonds along its backbone, based on the total number of bonds along its backbone, excluding the number of bonds of styrene groups, vinyl groups, ethyl groups and other side groups of the styrene-butadiene rubber; and (iii) 90% to 99% hydrogenated double bonds.

[0027] Although some embodiments of the rubber composition have been explicitly given above, all the features of the rubber composition already mentioned with respect to the (first) rubber component and its composition of the tire may also be present in the rubber composition described separately in this embodiment.

[0028] In an embodiment, the rubber composition may include at least one and / or an additional diene-based rubber. Representative synthetic polymers may be homopolymerization products of butadiene and its homologs and derivatives, such as methylbutadiene, dimethylbutadiene and pentadiene, as well as copolymers with other unsaturated monomers, such as those formed from butadiene or its homologs or derivatives. Among the latter may be acetylene, such as vinyl acetylene; olefins, such as isobutylene, which is copolymerized with isoprene to form butyl rubber; vinyl compounds, such as acrylic acid, acrylonitrile (which is polymerized with butadiene to form NBR), methacrylic acid and styrene (which is polymerized with butadiene to form SBR), as well as vinyl esters and various unsaturated aldehydes, ketones and ethers, such as acrolein, methyl isopropenyl ketone and vinyl ethyl ether. Specific examples of synthetic rubbers include neoprene (polychloroprene), polybutadiene (including cis 1,4-polybutadiene), polyisoprene (including cis 1,4-polyisoprene), butyl rubber, halobutyl rubber, such as chlorobutyl rubber or bromobutyl rubber, styrene / isoprene / butadiene rubber, copolymers of 1,3-butadiene or isoprene with monomers such as styrene, acrylonitrile and methyl methacrylate, and ethylene / propylene terpolymers, also known as ethylene / propylene / diene monomer (EPDM), and in particular ethylene / propylene / dicyclopentadiene terpolymers. Additional examples of rubbers that may be used include alkoxysilyl end-functionalized solution polymerized polymers (SBR, PBR, IBR and SIBR), silicon-coupled, and tin-coupled star-branched polymers. Preferred rubbers or elastomers may generally be natural rubber, synthetic polyisoprene, polybutadiene and SBR, including SSBR.

[0029] In another embodiment, the composition may include at least two diene-based rubbers, such as cis 1,4-polyisoprene rubber (natural or synthetic, but natural is preferred), 3,4-polyisoprene rubber, styrene / isoprene / butadiene rubber, emulsion and solution polymerization derived styrene / butadiene rubber, cis 1,4-polybutadiene rubber, and butadiene / acrylonitrile copolymers prepared by emulsion polymerization.

[0030] In another embodiment, emulsion polymerization derived styrene / butadiene (ESBR) having a styrene content of 20-35 percent bound styrene, or for some applications, ESBR having a moderate to relatively high bound styrene content, i.e., 30-45 percent bound styrene content, may be used. Emulsion polymerization prepared ESBR may mean that styrene and 1,3-butadiene are copolymerized as an aqueous emulsion. Such is well known to those skilled in the art. The bound styrene content may vary, for example, from 5 to 50 percent. In one embodiment, the ESBR may also contain acrylonitrile to form a terpolymer rubber as the ESBAR, for example, in an amount of 2-30 percent bound acrylonitrile in the terpolymer. Emulsion polymerization prepared styrene / butadiene / acrylonitrile copolymer rubber containing 2-40 percent bound acrylonitrile in the copolymer may also be contemplated as a diene-based rubber.

[0031] In another embodiment, solution polymerization prepared SBR (SSBR) may be used. Such SSBR may have a bound styrene content ranging, for example, from 5 to 50, preferably from 9 to 36 percent. SSBR may be conveniently prepared, for example, by anionic polymerization in an inert organic solvent. In particular, SSBR may be synthesized by copolymerization of styrene and 1,3-butadiene monomers in a hydrocarbon solvent using an organolithium compound as an initiator.

[0032] In one embodiment, synthetic or natural isoprene rubber may be used. Synthetic cis 1,4-polyisoprene and cis 1,4-polyisoprene natural rubber are well known per se to those skilled in the rubber art. In particular, the cis 1,4-content may be at least 90%, and in some cases at least 95%.

[0033] In one embodiment, cis 1,4-polybutadiene rubber (BR or PBD) is used. Suitable butadiene rubbers can be prepared, for example, by organic solution polymerization of 1,3-butadiene. BR can be conveniently characterized, for example, as having at least 90 percent cis 1,4-content ("high cis" content) and a glass transition temperature Tg in the range of -95 to -110°C. Suitable polybutadiene rubbers are commercially available from The Goodyear Tire & Rubber Company, such as Budene® 1207, Budene® 1208, Budene® 1223 or Budene® 1280. These high cis-1,4-polybutadiene rubbers can be synthesized using a nickel catalyst system including a mixture of (1) an organonickel compound, (2) an organoaluminum compound, and (3) a fluorine-containing compound, as described, for example, in U.S. Pat. Nos. 5,698,643 and 5,451,646, which are incorporated herein by reference.

[0034] The glass transition temperature, or Tg, of an elastomer or elastomeric composition, as referred to herein, refers to the glass transition temperature of the respective elastomer or elastomeric composition in its uncured state, or possibly in the case of elastomeric compositions, in the cured state. Tg is determined by differential scanning calorimetry (DSC) according to ASTM D3418 as the peak midpoint at a temperature ramp rate of 10° C. per minute.

[0035] The term "phr" as used herein and according to conventional practice refers to "parts by weight of each material per 100 parts by weight of rubber or elastomer." Generally, using this convention, a rubber composition is composed of 100 parts by weight of rubber / elastomer. A claimed composition may contain rubbers / elastomers other than those explicitly recited in the claim, so long as the phr values ​​of the claimed rubbers / elastomers are consistent with the phr ranges of the claim and the amounts of all rubbers / elastomers in the composition result in a total of 100 parts rubber. By way of example, the composition may further contain 1 to 10 phr, and in some cases 1 to 5 phr, of one or more additional diene-based rubbers, such as SBR, SSBR, ESBR, PBD / BR, NR, and / or synthetic polyisoprene. In another example, the composition may contain less than 5 phr, preferably less than 3 phr, of additional diene-based rubbers, or may also be essentially free of such additional diene-based rubbers. The terms "compound" and "composition" may be used interchangeably herein unless otherwise indicated.

[0036] In an embodiment, the rubber composition may also include oil, particularly process oil. The process oil may be included in the rubber composition as an extender oil typically used to extend elastomers. The process oil may also be included in the rubber composition by direct addition of the oil during rubber compounding. The process oil used may be included in both the extender oil present in the elastomer and the process oil added during compounding. Suitable process oils may include various oils known in the art, including aromatic, paraffinic, naphthenic, vegetable oils, and low PCA oils such as MES, TDAE, SRAE, and heavy naphthenic oils. Suitable low PCA oils may include those having a polycyclic aromatic content of less than 3 weight percent as determined by the IP346 method. The procedure for the IP346 method can be found in Standard Methods for Analysis & Testing of Petroleum and Related Products and British Standard 2000 Parts, 2003, 62nd Edition, published by the Institute of Petroleum, United Kingdom.

[0037] In an embodiment, the rubber composition may include silica. Commonly used siliceous pigments that may be used in rubber compounds include, for example, conventional pyrogenic and precipitated siliceous pigments (silica). In one embodiment, precipitated silica is used. The conventional siliceous pigment may be, for example, precipitated silica, such as those obtained by acidification of a soluble silicate, e.g., sodium silicate. Such conventional silicas may be characterized as having a BET surface area, for example, as measured using nitrogen gas. In one embodiment, the BET surface area may be in the range of 40 to 600 square meters per gram. In another embodiment, the BET surface area may be in the range of 80 to 300 square meters per gram. The BET method of measuring surface area is described in Journal of the American Chemical Society, Vol. 60, p. 304 (1930). Conventional silicas may also be characterized as having a dibutyl phthalate (DBP) absorption value in the range of 100 to 400, alternatively 150 to 300. Conventional silicas can be expected to have an average ultimate particle size in the range of 0.01 to 0.05 microns, for example as determined by electron microscopy, although silica particles may be smaller or possibly larger in size. The range of use of silica may range, for example, between 5 and 120 phr, preferably between 20 and 70 phr or between 80 and 120 phr. Various commercially available silicas may be used, such as, for example and not limited to, silicas available under the Hi-Sil trademark from PPG Industries, with designations such as 210, 315G, EZ160G, etc.; silicas available from Solvay, with designations such as Z1165MP and Premium200MP, and silicas available from Evonik AG, with designations such as VN2 and Ultrasil 6000GR, 9100GR, etc.

[0038] In an embodiment, the rubber composition may also include carbon black. Representative examples of such carbon black include grades N110, N121, N134, N220, N231, N234, N242, N293, N299, N315, N326, N330, N332, N339, N343, N347, N351, N358, N375, N539, N550, N582, N630, N642, N650, N683, N754, N762, N765, N774, N787, N907, N908, N990, and N991. These carbon blacks have an iodine absorption in the range of 9 g / kg to 145 g / kg, and an iodine content of 34 cm. 3 / 100g~150cm 3 / 100g range of DBP numbers.

[0039] In another embodiment, other fillers may be used in the rubber composition including, but not limited to, particulate fillers including ultra-high molecular weight polyethylene (UHMWPE), crosslinked particulate polymer gels including, but not limited to, those disclosed in U.S. Patent No. 6,242,534; U.S. Patent No. 6,207,757; U.S. Patent No. 6,133,364; U.S. Patent No. 6,372,857; U.S. Patent No. 5,395,891 or U.S. Patent No. 6,127,488, and plasticized starch composite fillers including, but not limited to, those disclosed in U.S. Patent No. 5,672,639. Other such fillers may be used in amounts ranging from 1 to 10 phr.

[0040] In one embodiment, the rubber composition may include a conventional sulfur-containing organosilicon compound or silane. Examples of suitable sulfur-containing organosilicon compounds include those having the formula: Z-Alk-S n -Alk-Z I wherein Z is

[0041] [ka]

[0042] wherein R1 is an alkyl group of 1 to 4 carbon atoms, cyclohexyl or phenyl; R 2 is an alkoxy of 1 to 8 carbon atoms, or a cycloalkoxy of 5 to 8 carbon atoms; Alk is a divalent hydrocarbon of 1 to 18 carbon atoms, and n is an integer of 2 to 8. In one embodiment, the sulfur-containing organosilicon compound is a 3,3'-bis(trimethoxy or triethoxysilylpropyl) polysulfide. In one embodiment, the sulfur-containing organosilicon compound is a 3,3'-bis(triethoxysilylpropyl) disulfide, and / or a 3,3'-bis(triethoxysilylpropyl) tetrasulfide. Thus, for formula I, Z is

[0043] [ka]

[0044] [Wherein, R 2 is an alkoxy of 2 to 4 carbon atoms, alternatively 2 carbon atoms; Alk is a divalent hydrocarbon of 2 to 4 carbon atoms, alternatively 3 carbon atoms; n is an integer 2 to 5, alternatively 2 or 4. In another embodiment, suitable sulfur-containing organosilicon compounds include those disclosed in U.S. Pat. No. 6,608,125. In one embodiment, the sulfur-containing organosilicon compound includes 3-(octanoylthio)-1-propyltriethoxysilane, CH3(CH2)6C(=O)-S-CH2CH2CH2Si(OCH2CH3)3, available commercially as NXT™ from Momentive Performance Materials. In another embodiment, suitable sulfur-containing organosilicon compounds include those disclosed in U.S. Patent Application Publication No. 2003 / 0130535. In one embodiment, the sulfur-containing organosilicon compound is Si-363 from Degussa. The amount of sulfur-containing organosilicon compound in the rubber composition may vary depending on the level of other additives used. Generally speaking, the amount of compound may range from 0.5 to 20 phr. In one embodiment, the amount will range from 1 to 10 phr.

[0045] It will be readily understood by those skilled in the art that the rubber composition can be compounded by methods commonly known in the rubber compounding art, such as, for example, mixing the various components of the sulfur vulcanizable rubber with various commonly used additive materials, such as sulfur donors, curing aids, e.g., activators and retarders, and processing additives such as oils, resins including tackifiers and plasticizers, fillers, pigments, fatty acids, zinc oxide, waxes, antioxidants and antiozonants and peptizers. Depending on the intended use of the sulfur vulcanizable and sulfur vulcanized materials (rubbers), as known to those skilled in the art, the additives listed above are selected and generally used in conventional amounts. Representative examples of sulfur donors include elemental sulfur (free sulfur), amine disulfides, polymeric polysulfides, and sulfur olefin adducts. In one embodiment, the sulfur vulcanizing agent is elemental sulfur. The sulfur vulcanizing agent may be used in an amount ranging from, for example, 0.5 phr to 8 phr, alternatively 1.5 phr to 6 phr. Typical amounts of tackifying resins, if used, include, for example, 0.5 phr to 10 phr, usually 1 phr to 5 phr. Typical amounts of processing aids, if used, include, for example, 1 phr to 50 phr (which may include, inter alia, oils). Typical amounts of antioxidants, if used, may include, for example, 1 phr to 5 phr. Representative antioxidants may be, for example, diphenyl-p-phenylenediamine and others, such as those disclosed in The Vanderbilt Rubber Handbook (1978), pages 344-346. Typical amounts of antiozonants, if used, may include, for example, 1 phr to 5 phr. Typical amounts of fatty acids, which may include stearic acid, if used, may include, for example, 0.5 phr to 3 phr. Typical amounts of waxes, if used, may include, for example, 1 phr to 5 phr. Often microcrystalline waxes are used. Typical amounts of peptizers, if used, may include, for example, 0.1 phr to 1 phr. Typical peptizing agents may be, for example, pentachlorothiophenol and dibenzamidodiphenyl disulfide.

[0046] Accelerators are preferably used to control the time and / or temperature required for vulcanization and to improve the properties of the vulcanizate, but may not be necessary. In one embodiment, a single accelerator system may be used, i.e., a primary accelerator. The primary accelerator(s) may be used in a total amount ranging from 0.5 phr to 4 phr, alternatively 0.8 phr to 1.5 phr. In another embodiment, a combination of primary and secondary accelerators may be used, with the secondary accelerator being used in a lower amount, such as 0.05 phr to 3 phr, to activate and improve the properties of the vulcanizate. These accelerator combinations can be expected to produce a synergistic effect on the final properties, which are somewhat better than those produced by the use of either accelerator alone. In addition, delayed action accelerators may also be used, which are not affected by normal processing temperatures but produce a satisfactory cure at ordinary vulcanization temperatures. Vulcanization retarders may also be used. Suitable types of accelerators that may be used in the present invention are, for example, amines, disulfides, guanidines, thioureas, thiazoles, thiurams, sulfenamides, dithiocarbamates, and xanthates. In one embodiment, the primary accelerator is a sulfenamide. If a second accelerator is used, the secondary accelerator may be, for example, a guanidine, dithiocarbamate, or thiuram compound. Suitable guanidines include diphenylguanidine, etc. Suitable thiurams include tetramethylthiuram disulfide, tetraethylthiuram disulfide, and tetrabenzylthiuram disulfide.

[0047] Mixing of the rubber composition can be accomplished by methods known to those skilled in the rubber mixing art. For example, the raw materials may typically be mixed in at least two stages, namely, at least one non-productive stage followed by a productive mix stage. The final curatives, including sulfur vulcanizing agents, may typically be mixed in a final stage, conventionally referred to as the "productive" mix stage, where mixing is typically performed at a temperature or at a final temperature that is lower than the mixing temperature(s) of the preceding non-productive mix stage(s). The terms "non-productive" and "productive" mix stages are well known to those skilled in the rubber mixing art. In an embodiment, the rubber composition may be subjected to a thermomechanical mixing step. The thermomechanical mixing step generally involves mechanical operation in a mixer or extruder for a period of time suitable to produce a rubber temperature, which is typically in the range of, for example, 140°C to 190°C. The suitable duration of the thermomechanical operation varies as a function of the operating conditions and the amounts and nature of the components. For example, the thermomechanical operation may be from 1 to 20 minutes.

[0048] The rubber composition can be incorporated into various rubber components of a tire (in other words, tire components). For example, the rubber component can be the tread (including the tread cap and tread base), sidewall, apex, chafer, sidewall insert, wire coat, or innerliner.

[0049] The tire of the present invention may be, for example, a pneumatic or non-pneumatic tire, a race tire, a passenger tire, an aircraft tire, a farm tire, an earthmoving tire, an off-the-road (OTR) tire, a truck tire or a motorcycle tire. The tire may also be a radial or bias tire. Vulcanization of the pneumatic tire of the present invention may be carried out at conventional temperatures, for example, in the range of 100°C to 200°C. In one embodiment, vulcanization is carried out at a temperature in the range of 110°C to 180°C. Any of the usual vulcanization methods may be used, such as heating in a press or mold, heating with superheated steam or hot air, etc. Such tires may be built, shaped, molded and cured by various methods known and readily apparent to those skilled in the art.

[0050] Many features of the aspects and embodiments described herein can be combined with each other. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0051] DETAILED DESCRIPTION OF EMBODIMENTS OF THE PRESENTINVENTION Table 1 below shows the rubber compositions for the first rubber compound. Control 1 and Inventive Example 1 contain hydrogenated SSBR. However, only Inventive Example 1 contains polyoctenamer according to a non-limiting embodiment of the present invention. The second control sample, Control 2, contains non-hydrogenated SSBR blended with polybutadiene without polyoctenamer.

[0052] [Table 1]

[0053] The composition shown in Table 1 above was included in a tread cap layer and co-cured to a tread base layer having the composition shown in Table 2 below, as a non-limiting example.

[0054] [Table 2]

[0055] The properties of Control 1, Control 2 and Inventive Example 1 were determined as shown in Table 3. The tear strength of each sample of Control 1, Control 2 and Inventive Example 1 of the second compound shown in Table 2 is shown in the first row of Table 3. The tear strength is relatively high for compound Control 2, while Control 1 has a significantly lower tear strength relative to the base compound. In other words, it is easier to tear or pull the Control 1 compound containing hydrogenated SSBR away from the second compound shown in Table 2. The addition of polyoctenamer as present in Inventive Example 1 noticeably improves the tear strength behavior, despite the use of hydrogenated SSBR. The rebound value, which is an indication of the hysteresis behavior of the compound and therefore also the expected rolling resistance, is also slightly but clearly improved for Inventive Example 1 compared to the control sample. The Shore A hardness also remains at a comparable level of the control sample. Finally, as previously mentioned, the presence of hydrogenated SSBR in Control 1 and Inventive Example 1 results in a significant increase in tensile strength, greater than 50%, compared to Control 2. Inventive Example 1 is at least able to maintain a level of tear strength relative to the base, or in other words still allows for good co-cure. Hysteresis behavior is also improved.

[0056] [Table 3]

[0057] While certain representative embodiments and details have been shown for the purpose of illustrating the subject invention, it will be apparent to those skilled in the art that various changes and modifications can be made in the present invention without departing from the scope of the subject invention.

Claims

1. A tire comprising a first rubber component and a second rubber component, the first rubber component is cured against the second rubber component; The first rubber component Hydrogenated styrene-butadiene rubber 85 phr to 100 phr; Polybutadiene 0 phr to 15 phr; Polyoctenamer 5 phr to 20 phr; a first filler comprising 40 phr to 160 phr; The second rubber component 90 phr to 100 phr of a diene-based elastomer; and The tire comprises: a second filler in an amount of from 20 phr to 160 phr.

2. the first rubber component comprises 95 to 100 phr of the hydrogenated styrene-butadiene rubber and 0 to 5 phr of the polybutadiene; and / or said first rubber component comprising from 5 phr to 15 phr of said polyoctenamer; and / or 2. The tire of claim 1, wherein the first rubber component comprises 60 to 80 phr of silica.

3. the diene-based elastomer comprises polyisoprene or polybutadiene or a combination thereof; and / or The second rubber component 30 phr to 90 phr polyisoprene; 10 phr to 70 phr polybutadiene; and 3. Tire according to claim 1, characterized in that it contains from 30 phr to 70 phr of carbon black.

4. the tire has a tread and the first rubber component and the second rubber component are components of the tread; and / or 4. A tire according to claim 1, wherein the first rubber component is cured against the second rubber component essentially along a cylindrical surface extending circumferentially around the tire.

5. The tire as described in claim 4, wherein the first rubber component is a tread cap layer of the tread, and the second rubber component is a second tread cap layer or a tread base layer of the tread.

6. The hydrogenated styrene-butadiene rubber is i) less than 5% non-hydrogenated vinyl groups, based on the total number of vinyl and ethyl groups of the hydrogenated styrene-butadiene rubber; ii) less than 2% double bonds along the backbone, based on the total number of bonds along its backbone, excluding the number of bonds of styrene, vinyl, ethyl and other side groups of the styrene-butadiene rubber; and (iii) 90% to 99% hydrogenated double bonds 6. A tire according to claim 1, characterized in that it comprises one or more of the following:

7. the polybutadiene has a glass transition temperature in the range of -90°C to -115°C; and / or the hydrogenated styrene-butadiene rubber has a glass transition temperature in the range of -20°C to -50°C; and / or 7. Tire according to any one of claims 1 to 6, characterized in that the styrene-butadiene rubber has a bound styrene content ranging from 20% to 35% by weight, and a butadiene content ranging from 50% to 80% by weight.

8. Tire according to any one of claims 1 to 7, characterized in that the first rubber component comprises between 5 phr and 25 phr of oil, and 5 phr to 30 phr of a plasticizer comprising a resin, between 15 phr and 30 phr.

9. the resin is an alpha-pinene based resin; and / or 9. The tire of claim 8, wherein the ratio of said resin to said oil is between 1:1 and 1:4 phr.

10. The polyoctenamer is A glass transition temperature in the range of -50°C to -80°C; Molecular weight M between 80,000 and 100,000 as determined by GPC Ｗ ; A melting point on the second heat between 45° C. and 55° C. as measured by DSC; Between 65% and 85% trans double bonds 10. A tire according to claim 1, characterized in that it comprises one or more of the following:

11. Hydrogenated styrene-butadiene rubber; Polyoctenamer 5 phr to 20 phr; and A rubber composition comprising 40 phr to 160 phr of a filler.

12. 85 phr to 100 phr of said hydrogenated styrene-butadiene rubber; 5 phr to 15 phr of a high cis-polybutadiene rubber having at least 95% cis microstructure content; and Oil 5 phr to 25 phr, and resin 5 phr to 30 phr The rubber composition of claim 11 further comprising one or more of:

13. The rubber composition of claim 12, wherein the resin is an alpha-pinene resin.

14. The hydrogenated styrene-butadiene rubber is i) less than 5% non-hydrogenated vinyl groups, based on the total number of vinyl and ethyl groups of the hydrogenated styrene-butadiene rubber; ii) less than 2% double bonds along the backbone, based on the total number of bonds along its backbone, excluding the number of bonds of styrene, vinyl, ethyl and other side groups of the styrene-butadiene rubber; and (iii) 90% to 99% hydrogenated double bonds The rubber composition according to any one of claims 11 to 13, characterized in that it has one or more of the following:

15. A tire component comprising the rubber composition of any one of claims 11 to 14.

16. A tire comprising the tire component of claim 15.

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