Tyre incorporating a rubber composition comprising a specific hydrocarbon resin

Abstract

The present invention relates to a tyre comprising a rubber composition based on at least: - an elastomer matrix comprising a styrene-butadiene copolymer A having a Tg(A) that varies in a range from -100°C to -60°C, and a styrene-butadiene copolymer B having a Tg(B) that varies in a range from -70°C to -40°C, where 10°C ≤Tg(B)-Tg(A) ≤ 60°C, the Tg being measured according to the ASTM D3418-12 standard; - a reinforcing filler comprising silica; - a vulcanisation system; and - a plasticising system comprising a hydrocarbon resin, which resin is based on a cyclic monomer selected from the group consisting of a distillation cut derived from a petroleum refinery stream, C4, C5 and C6 cyclic olefins and mixtures thereof, and which hydrocarbon resin has an aromatic proton content (H Ar, expressed in mol%), a glass transition temperature (Tg, expressed in °C) and a number average molecular weight (Mn, expressed in g / mol) such that (1) H Ar > 6 mol% (2) Tg ≥ 95 - 2.2 * (H Ar), (3) Tg ≥ -53 + (0.265 * Mn) and (4) 250 g / mol ≤ Mn ≤ 600 g / mol.

Description

[0001] Tire incorporating a rubber composition comprising a specific hydrocarbon resin

[0002] technical field

[0003] The present invention relates to tires comprising rubber compositions including a specific hydrocarbon resin.

[0004] Previous technique

[0005] Tire manufacturers are constantly seeking ways to improve tire performance. This research involves continuously improving the properties of the rubber compounds used in tire manufacturing. The compounds that make up a tire generally represent compromises between performance properties that are difficult to reconcile simultaneously. Therefore, it is an ongoing objective for tire manufacturers to find formulas that improve the balance between all these performance properties.

[0006] It is known from prior art to combine hydrocarbon plasticizing resins with elastomeric matrices in order to balance properties such as wear resistance and adhesion, which must be high, and rolling resistance, which must be low to minimize fuel consumption. There is extensive literature concerning the use of hydrocarbon resins in rubber compounds.

[0007] Document WO2013 / 176712 describes various cyclopentadiene / dicyclopentadiene / methylcyclopentadiene resins with specific masses and softening points. In this document, these resins are used in the disclosed examples to improve wet adhesion.

[0008] Documents WO2017 / 064235 and WO2017 / 168099 also describe various cyclopentadiene / dicyclopentadiene / methylcyclopentadiene type resins, and their use in tires with high adhesion and low rolling resistance.

[0009] Furthermore, the Applicant has demonstrated in the past that combining an elastomer, particularly SBR or BR, with a specific hydrocarbon resin based on a cyclic monomer exhibiting a certain aromaticity, produces tires with improved road handling at various temperatures. Documents WO202118547A1, WO202118548A1, and WO2022161742A1 are examples of this.

[0010] Description of the invention

[0011] The Applicant has now shown that a particular composition comprising a specific hydrocarbon resin combined with a particular blend of elastomers makes it possible to obtain compositions exhibiting improved breaking strength and therefore improved tensile strength, which suggests improved durability for a tire incorporating such a composition. The invention relates to such tires, as described in more detail below. Summary of the invention

[0012] The invention, described in more detail below, relates to at least one of the implementations listed in the following points:

[0013] 1. Tire comprising a rubber composition based on at least:

[0014] - an elastomeric matrix comprising a styrene-butadiene copolymer A with Tg(A) varying in a range from -100°C to -60°C and a styrene-butadiene copolymer B with Tg(B) varying in a range between -70°C and -40°C, with 10°C <Tg(B)-Tg(A)< 60°C, la Tg étant mesurée par ASTM D3418-12,

[0015] - a reinforcing load,

[0016] - a vulcanization system and

[0017] - a plasticizing system comprising a hydrocarbon resin, which resin is based on a cyclic monomer selected from the group consisting of a distillation cut from a petroleum refinery stream, C4, C5 and C6 cyclic olefins and mixtures thereof, and which hydrocarbon resin has an aromatic proton content (H₂Ar, expressed in mol%), a glass transition temperature (Tg, expressed in °C) and a number-average molecular weight (Mn, expressed in g / mol) such that

[0018] H Ar > 6%mol,

[0019] (2) Tg > 95 - 2.2

[0020] (3) Tg > -53 + (0,

[0021] (4) 250 g / mol < Mn < 600 g / mol.

[0022] 2. Tyre according to embodiment 1, in which the styrene-butadiene copolymer B has a Tg(B) varying in a range from -60°C to -40°C.

[0023] 3. Tire according to embodiment 1 or 2, in which the Tgs of the styrene-butadiene copolymers (A) and (B) are such that 15°C <Tg(B)-Tg(A)< 50°C.

[0024] 4. Tyre according to any one of the preceding embodiments, in which the styrene-butadiene copolymer (A) has a Tg(A) varying in a range from -90°C to -70°C.

[0025] 5. Tire according to any one of the preceding embodiments, in which the elastomer matrix comprises from 20 pc to 70 pc of styrene-butadiene copolymer (B), preferably from 30 pc to 70 pc.

[0026] 6. Tire according to any one of the preceding embodiments, in which the elastomer matrix comprises from 20 pc to 70 pc of styrene-butadiene copolymer (A), preferably from 30 pc to 70 pc.

[0027] 7. A tire according to any one of the preceding embodiments, in which the elastomeric matrix comprises from 30% to 50% of styrene-butadiene copolymer (A) and from 50% to 70% of styrene-butadiene copolymer (B). 8. A tire according to any one of the preceding embodiments, in which at least one of the styrene-butadiene copolymers (A) and (B) is functionalized and bears at least one silanol or alkoxysilyl -SiOR group, R representing a C1-C8 alkyl radical, preferably C1-C4.

[0028] 9. Tyre according to any one of the preceding embodiments, in which the styrene-butadiene copolymers (A) and (B) are functionalized and bear at least one silanol or alkoxysilyl -SiOR function, R representing a C1-C8 alkyl radical, preferably C1-C4.

[0029] 10. Tire according to any one of the preceding embodiments, in which the silanol or alkoxysilyl -SiOR function, R representing an alkyl radical in C1-C8, preferably C1-C4, bears a group comprising another function comprising at least one heteroatom selected from N, S, O, P, said other function being attached to the silicon atom of the silanol or alkoxysilyl function, by a covalent bond or by a spacer, the spacer being a divalent linear aliphatic group in C1-C10, preferably C1-C6, preferably again C1-C4.

[0030] 11. Tyre according to any one of the preceding embodiments, in which the silanol or alkoxysilyl function -SiOR, R representing a C1-C8 alkyl radical, preferably C1-C4, carries a group comprising another function selected from the primary, protected or unprotected, secondary, protected or unprotected, or tertiary amine functions of formula -NR'a, each of the R's independently representing a hydrogen atom or a Cl-C8 alkyl radical, preferably C1-C4, the glycidyloxy and epoxy functions, and the thiol function -SH, protected or unprotected.

[0031] 12. Tire according to any one of the preceding embodiments, in the silanol or alkoxysilyl function -SiOR, R representing an alkyl radical in C1-C8, preferably C1-C4, carries a group comprising another function chosen from among the tertiary amine functions, of formula -NR'a, each of the R's independently representing an alkyl radical in C1-C4, preferably the R's are all identical.

[0032] 13. Tire according to any one of the preceding embodiments, in which at least one of the styrene-butadiene copolymers (A) and (B), preferably both, is functionalized and bears at least one >SiOR(Sp-NR'3) group, the Si atom being in the main chain of the copolymer, R representing a C1-C8 alkyl radical, preferably C1-C4, or a hydrogen atom, R' representing a C1-C4 alkyl radical, and Sp being a linear divalent aliphatic group in C1-C6, preferably again C1-C4, the symbol ">" indicates that the silicon atom is bonded to 2 carbon atoms of the main polymer chain.

[0033] 14. A tire according to any one of the preceding embodiments, wherein the hydrocarbon resin is further characterized by a Tg of 70°C to 95°C, preferably 70°C to 90°C. 15. A tire according to any one of the preceding embodiments, wherein the hydrocarbon resin is further characterized by an aromatic proton content of 12 mol% < H Ar < 19 mol%.

[0034] 16. Tire according to any of the preceding embodiments, in which the hydrocarbon resin comprises the cyclic monomer in an amount from 10% by weight to 90% by weight, preferably in an amount from 25% by weight to 80% by weight, of the total weight of the resin.

[0035] 17. Tire according to any one of the preceding embodiments, wherein the cyclic monomer is selected from the group consisting of cyclopentene, cyclopentadiene, dicyclopentadiene, cyclohexene, 1,3-cyclohexadiene, 1,4-cyclohexadiene, methylcyclopentadiene, di(methylcyclopentadiene) and mixtures thereof.

[0036] 18. Tire according to any one of the preceding embodiments, wherein the cyclic monomer is chosen from the group consisting of dicyclopentadiene, cyclopentadiene, methylcyclopentadiene and mixtures thereof.

[0037] 19. Tire according to any one of the preceding embodiments in which the cyclic monomer comprises cyclopentadiene.

[0038] 20. Tyre according to any of the preceding embodiments, in which the hydrocarbon resin comprises methylcyclopentadiene in an amount from 0.1% by weight to 15% by weight, preferably from 0.1% by weight to 5% by weight.

[0039] 21. Tire according to any one of the preceding embodiments, wherein the resin is further based on an aromatic monomer.

[0040] 22. Tire according to any of the preceding embodiments, wherein the resin is further based on an aromatic monomer in an amount ranging from 10% by weight to 90% by weight, preferably in an amount ranging from 20% by weight to 75% by weight of the weight of the resin.

[0041] 23. Tire according to any one of embodiments 21 and 22, wherein the aromatic monomer is chosen from the group consisting of aromatic olefin compounds, aromatic distillation cuts and mixtures thereof.

[0042] 24. Tire according to the preceding embodiment, wherein the aromatic monomer comprises an aromatic distillation cut, preferably a distillation cut comprising at least one of styrene, alkyl substituted derivatives of styrene, indene, alkyl substituted derivatives of indene, and mixtures thereof.

[0043] 25. Tyre according to any one of embodiments 21 and 23, wherein the aromatic monomer comprises an olefinic-aromatic compound selected from the group consisting of indene derivatives, vinylaromatic compounds and mixtures thereof.

[0044] 26. Tire according to the preceding embodiment, in which the aromatic monomer comprises an indene derivative of Formula (I) in which RI and R2 represent, independently of each other, a hydrogen atom, an alkyl group, an alkenyl group, a cycloalkyl group, an aryl group or an arylalkyl group.

[0045] 27. A tire according to any one of the preceding embodiments, in which the hydrocarbon resin has at least one and preferably all of the following additional characteristics:

[0046] - an average molecular mass by number (Mn) ranging from 300 to 450 g / mol,

[0047] - a glass transition temperature (Tg) represented by Tg > 100 - 2.2* (H Ar),

[0048] - a glass transition temperature (Tg) represented by Tg > -32 + (0.265*Mn).

[0049] 28. Tyre according to any of the preceding embodiments, wherein the content of said hydrocarbon resin is in a range of 15 to 150 parts per annum and preferably of 25 to 120 parts per annum.

[0050] 29. Tire according to any of the preceding embodiments, in which the reinforcing load ratio is within a range of 40 to 200 pc.

[0051] 30. Tyre according to any of the preceding embodiments, in which the reinforcing filler comprises silica as the major reinforcing filler.

[0052] 31. Tyre according to any of the preceding embodiments, in which the silica content is within a range of 40 to 160 parts per annum.

[0053] Definitions

[0054] The term "part by weight per hundred parts by weight of elastomer" (or pce) is used in the context of this invention to mean the part by mass per hundred parts by mass of elastomer. Furthermore, any range of values ​​designated by the expression "between a and b" represents the range of values ​​from greater than a to less than b (i.e., excluding the limits a and b), while any range of values ​​designated by the expression "from a to b" means the range of values ​​from a to b (i.e., including the strict limits a and b). In this invention, when a range of values ​​is designated by the expression "from a to b," it explicitly includes the range represented by the expression "between a and b."

[0055] When referring to a "major" compound, for the purposes of this invention, it is understood that this compound is the majority among the compounds of the same type in the composition; that is, it is the one that represents the largest quantity by mass among the compounds of the same type. Thus, for example, a major elastomer is the elastomer representing the greatest mass relative to the total mass of the elastomers in the composition. Similarly, a major filler is the one representing the greatest mass among the fillers in the composition. For example, in a system comprising a single elastomer, this elastomer is the major component for the purposes of this invention; and in a system comprising two elastomers, the major elastomer represents more than half the mass of the elastomers. Conversely, a "minor" compound is a compound that does not represent the largest mass fraction among the compounds of the same type.Preferably, by major, we mean a mass proportion of more than 50%; when the compound represents 100% by mass, it is also described as "major".

[0056] The term "alkoxy" refers to a radial -OR in which R represents an alkyl radical.

[0057] By "alkyl" we mean a saturated hydrocarbon radical, linear or branched, comprising from 1 to 20 carbon atoms, preferably from 1 to 10 carbon atoms, for example the methyl radical, ethyl radical, propyl radical, butyl radical, pentyl radical, hexyl radical, heptyl radical, octyl radical, nonyl radical and decyl radical.

[0058] By "divalent aliphatic group", we mean a divalent group, saturated or unsaturated, linear or branched, comprising from 1 to 20 carbon atoms, preferably from 1 to 10 carbon atoms, preferably still from 1 to 6 carbon atoms, the methanediyl group, ethanediyl, propanediyl, butanediyl, pentanediyl, hexanediyl radicals.

[0059] The compounds mentioned in the description can be of fossil origin or bio-based. In the latter case, they may be partially or entirely derived from biomass or obtained from renewable raw materials derived from biomass. Similarly, the compounds mentioned may also come from the recycling of previously used materials; that is, they may be partially or entirely produced through a recycling process, or obtained from raw materials themselves derived from a recycling process. This includes, in particular, polymers, plasticizers, fillers, etc.

[0060] Detailed description of the invention

[0061] Elastomer matrix

[0062] By "elastomer matrix", we mean all the elastomers in the composition.

[0063] According to the invention, the elastomeric matrix comprises a styrene-butadiene copolymer A with Tg(A) varying in a range from -100°C to -

[0064] 60°C and a styrene-butadiene copolymer B of Tg(B) varying in a range from -70°C to -40°C, with 10°C <Tg(B)-Tg(A)< 60°C, la Tg étant mesurée selon la norme ASTM D3418-12.

[0065] According to a particular embodiment of the invention, the styrene-butadiene copolymer (B) advantageously exhibits a Tg of -60°C to -40°C.

[0066] According to a particular embodiment of the invention, the styrene-butadiene copolymer (B) has a styrene content of 15% to 40% by weight, preferably 20% to 40% by weight of the total copolymer weight. According to this particular embodiment of the invention, the styrene-butadiene copolymer (B) advantageously has a vinyl unit content relative to the diene portion of the copolymer ranging from 10% to 60% by weight, preferably ranging from 20% to 40% by weight.

[0067] Preferably for the purposes of the invention, the styrene-butadiene copolymer (B) has a Tg in the range of -60°C to -40°C, a styrene content relative to the total weight of the copolymer of 20% to 40% by weight and a vinyl unit content relative to the diene portion of the copolymer of 20 to 40% by weight.

[0068] According to a particular embodiment of the invention, the styrene-butadiene copolymer (A) advantageously has a Tg of -90°C to -60°C. Most preferably, the styrene-butadiene copolymer has a Tg of -90 to -70°C.

[0069] According to a particular embodiment of the invention, the styrene-butadiene copolymer (A) has a styrene content of 1 to 20% by weight, preferably 1 to 5% by weight, of the total weight of the copolymer. According to this particular embodiment of the invention, the styrene-butadiene copolymer advantageously has a vinyl unit content relative to the diene portion of the copolymer ranging from 8 to 25% by weight, preferably ranging from 10 to 15% by weight.

[0070] Preferably for the purposes of the invention, the styrene-butadiene copolymer (A) has a Tg within a range of -90°C to -60°C, a styrene content relative to the total weight of the copolymer ranging from 1 to 20% by weight and a vinyl unit content relative to the diene portion of the copolymer ranging from 8 to 25% by weight.

[0071] Preferably, for the purposes of the invention, the styrene-butadiene copolymer (A) has a Tg in the range of -90°C to -80°C, a styrene content relative to the total weight of the copolymer ranging from 1 to 5% by weight and a vinyl unit content relative to the diene portion of the copolymer ranging from 8 to 15% by weight.

[0072] According to the invention, the Tg values ​​of styrene-butadiene copolymers (A) and (B) are such that 10°C <Tg(B)- Tg(A)< 60°C, de préférence 15°C <Tg(B)-Tg(A)< 50°C.

[0073] According to a preferred embodiment of the invention, the styrene-butadiene copolymer (A) has a Tg in the range of -90°C to -60°C, and the styrene-butadiene copolymer (B) has a Tg in the range of -60°C to -40°C.

[0074] According to another preferred embodiment of the invention, the styrene-butadiene copolymer (A) has a Tg in the range of -90°C to -80°C, and the styrene-butadiene copolymer (B) has a Tg in the range of -70°C to -40°C.

[0075] According to preferred embodiments of the invention, at least one of the styrene-butadiene copolymers (A) and (B) is functionalized and bears at least one silanol or alkoxysilyl SiOR group, R representing a C1-C8 alkyl radical, preferably C1-C4. More preferably, both styrene-butadiene copolymers (A) and (B) are functionalized and bear at least one silanol or alkoxysilyl -SiOR group, R representing a C1-C8 alkyl radical, preferably C1-C4.

[0076] According to these embodiments, the silanol or alkoxysilyl function also carries at least one other function, preferably linked to the silicon atom of the silanol or alkoxysilane function by a covalent bond or by a spacer, the spacer being a linear divalent aliphatic group in C1-C10, preferably C1-C6, preferably even more C1-C4.

[0077] The other function is a function comprising at least one heteroatom chosen from N, S, O, P. Examples of these functions include primary, secondary or tertiary amines, cyclic or non-cyclic, isocyanates, imines, cyano, the thiol function, carboxylates, epoxides and primary, secondary or tertiary phosphines.

[0078] According to preferred embodiments of the invention, the other function is selected from primary amine functions, protected or unprotected, secondary amine functions, protected or unprotected, or tertiary amine functions of formula -NR'3, each of the R's independently representing a hydrogen atom or an alkyl radical in the C1-C8 position, preferably in the C1-C4 position, the glycidyloxy and epoxy functions, and the thiol function -SH, protected or unprotected. According to these embodiments, the other function is preferably a tertiary amine function of formula -NR'3, each of the R's independently representing an alkyl radical in the C1-C4 position; advantageously, the R's are identical.

[0079] The silanol or alkoxysilyl group can be located at the end of the main chain of the copolymer. In this case, the diene elastomer is said to be end-functionalized. The silanol or alkoxysilyl group can also be located within the main chain of the copolymer. In this case, the diene elastomer is said to be coupled or mid-chain functionalized, as opposed to the "end-of-chain" position, even though the group is not located precisely in the middle of the elastomer chain. Those skilled in the art will understand that a functionalization reaction with an agent containing more than one reactive group with respect to the living elastomer results in a mixture of end- and mid-chain functionalized species, constituting the linear chains of the functionalized elastomer, as well as, where applicable, stellate species.

[0080] According to preferred embodiments of the invention, at least one of the styrene-butadiene copolymers (A) and (B), preferably both, is functionalized and bears at least one >SiOR(Sp-NR'3) group, the Si atom being in the main chain of the copolymer (mid-chain functionalization), R representing a C1-C8 alkyl radical, preferably C1-C4, preferably ethyl or methyl, or a hydrogen atom, R' representing a C1-C4 alkyl radical, preferably ethyl or methyl, and Sp being a divalent linear aliphatic group in the C1-C6 range, preferably C1-C4, preferably propyl. The symbol ">" indicates that the silicon atom is bonded to two carbon atoms of the main polymer chain.Functionalized styrene-butadiene copolymers can, for example, be obtained according to the processes described in documents US20050203251 Al, WO2015 / 018743A1, W02009 / 133068A1, WO 2017 / 060396, W02017 / 001683A1, W02007 / 047943 Al, EP1457501 Al. Functionalized styrene-butadiene copolymers described in WO2015 / 018743A1, W02009 / 133068A1, WO 2017 / 060396, W02017 / 001683A1 are particularly suitable.

[0081] According to a preferred embodiment of the invention, the elastomeric matrix comprises at least 20 parts per annum of styrene-butadiene copolymer (B), preferably at least 30 parts per annum.

[0082] According to a preferred embodiment of the invention, the elastomeric matrix predominantly comprises the styrene-butadiene copolymer (A). That is to say, the styrene-butadiene copolymer (A) is the major elastomer. According to this embodiment, the elastomeric matrix preferably comprises at least 50% of the styrene-butadiene copolymer (A).

[0083] Particularly according to this embodiment of the invention, the elastomeric matrix comprises at least 50 parts of styrene-butadiene copolymer and at least 20 parts of styrene-butadiene copolymer (B), preferably at least 30 parts.

[0084] According to one embodiment of the invention, the matrix consists of styrene-butadiene copolymer (A) and styrene-butadiene copolymer (B) and does not comprise any other diene elastomer. This definition, however, does not preclude the possibility of the presence of traces of other elastomers without any impact on the properties of the rubber composition.

[0085] According to another embodiment of the invention, in addition to the styrene-butadiene copolymer (A) and the styrene-butadiene copolymer (B), the matrix comprises at least one other diene elastomer. This diene elastomer is then preferably chosen from polybutadienes (BR), synthetic polyisoprenes (IR), butadiene copolymers other than styrene-butadiene copolymer (SBR), isoprene copolymers, natural rubber, and mixtures of these elastomers.

[0086] Preferably, for the purposes of the invention, the matrix consists of at least 20 parts per unit of styrene-butadiene copolymer (B) and at most 80 parts per unit of styrene-butadiene copolymer (A) and does not comprise any other diene elastomer. Preferably, the matrix consists of 20 to 50 parts per unit of styrene-butadiene copolymer (B) and 50 to 80 parts per unit of styrene-butadiene copolymer (A).

[0087] Reinforcing load

[0088] According to the invention, the rubber composition for the tire is based on a reinforcing filler comprising silica. The rubber composition of the invention may include another reinforcing filler besides silica.

[0089] Any type of reinforcing filler, known for its ability to strengthen a rubber compound suitable for use in tire manufacturing, can be used. Examples include organic fillers such as carbon black, inorganic fillers other than silica, or mixtures of these fillers. All carbon blacks are suitable, particularly those conventionally used in tires or their treads. Among these, reinforcing carbon blacks of the 100, 200, and 300 series, or those of the 500, 600, and 700 series (ASTM D-1765-2017 grades), such as N115, N134, N234, N326, N330, N339, N347, N375, N550, N683, and N772, are particularly noteworthy. These carbon blacks can be used in their isolated state, as commercially available, or in any other form, for example as a carrier for some of the rubberizing additives used.Carbon blacks could, for example, already be incorporated into the elastomer matrix in the form of a masterbatch (see, for example, applications WO97 / 36724-A2 or W099 / 16600-A1).

[0090] As reinforcing inorganic fillers, other than silica, mineral fillers of the aluminous type, in particular alumina (Al2O3), are suitable.

[0091] The silica used can be any reinforcing silica known to those skilled in the art, in particular any precipitated or fumed silica having a specific surface area BET and a specific surface area CTAB both less than 450 m² / g, preferably within a range of 30 to 400 m² / g, and in particular from 60 to 300 m² / g. Precipitated silica can be produced from non-renewable raw materials, in particular those derived from inorganic sand (silicon dioxide from inorganic sand), from recycled materials such as foundry sands, end-of-life tires, and in particular the treads of end-of-life tires consisting mainly of silica as a reinforcing filler, or from bio-based raw materials such as organic waste from plants, preferably inedible organic waste from plants.Among the plants containing silicon dioxide in their tissues are mustard, grasses, corn, sugarcane bagasse, rice, wheat, and in particular mustard husks, bamboo leaves, corn cobs, wheat husks, and rice husks. For example, and quite well known, silica derived from rice husk ash is called RHA silica (Rice Husk Ash Silica). Bio-based silicas are available from suppliers such as Solvay, Evonik, Quechen, Wilmar International, and Wuxi.

[0092] Any type of precipitated silica can be used, including highly dispersible precipitated silicas (known as "HDS" for "highly dispersible" or "highly dispersible silica"). These precipitated silicas, whether highly dispersible or not, are well known to those skilled in the art and are commercially available. Examples include the silicas described in applications W003 / 016215-A1 and W003 / 016387-A1. Among the commercially available HDS silicas, the following can be used: "Ultrasil® 5000GR" and "Ultrasil® 7000GR" from Evonik, and "Zeosil® 1085GR", "Zeosil® 1115 MP", "Zeosil® 1165 MP", "Zeosil® Premium 200 MP", and "Zeosil® HRS 1200 MP" from Solvay.As non-HDS silica, the following commercial silicas may be used: “Ultrasil ® VN2GR”, “Ultrasil ® VN3GR” silicas from Evonik, “Hi-Sil EZ120G(-D)”, “Hi-Sil EZ160G(-D)”, “Hi-Sil EZ200G(-D)”, “Hi-Sil 243LD”, “Hi-Sil 210”, “Hi-Sil HDP 320G” silicas from PPG, “K160”, “K185”, “K195” silicas from Wilmar International.

[0093] The physical state of the silica is irrelevant, whether it be in the form of powder, microbeads, granules, spheres, or any other suitable densified form. Of course, the term "silica" also includes mixtures of different silicas as described above. Those skilled in the art will understand that a reinforcing filler of another type may be used in place of the silica described above, provided that this reinforcing filler is coated with a layer of silica. Examples include carbon blacks partially or fully coated with silica, or carbon blacks modified with silica, such as, but not limited to, the "Ecoblack®" fillers in the CRX2000 series or the "CRX4000" series from Cabot Corporation.

[0094] A skilled professional will know how to adjust the total reinforcing compound and its type according to the intended use, particularly the type of tire or its compound. The total reinforcing compound typically ranges from 40 to 200 parts per cubic inch (ppc), more preferably from 45 to 180 ppc, and even more preferably from 50 to 160 ppc; the optimum is known to vary depending on the specific application.

[0095] According to a particular embodiment of the invention, the reinforcing filler comprises mainly silica, preferably comprising more than 50% silica by weight relative to the total weight of the reinforcing filler. In this embodiment, the silica is preferably used at a concentration in the range of 40 to 160 parts per cubic meter (ppm), preferably 40 to 150 ppm, or even 60 to 120 ppm. Optionally, in this embodiment, the reinforcing filler also comprises carbon black. In this option, the carbon black is used at a concentration of 20 ppm or less, more preferably 10 ppm or less (for example, the carbon black concentration may be in the range of 0.5 to 20 ppm, in particular from 1 to 10 ppm).Within the indicated ranges, we benefit from the coloring (black pigmenting agent) and anti-UV properties of carbon blacks, without penalizing the typical performance provided by the reinforcing inorganic filler.

[0096] In this presentation, the specific surface area BET is determined by gas adsorption using the Brunauer-Emmett-Teller method described in "The Journal of the American Chemical Society" (Vol. 60, page 309, February 1938), and more specifically according to a method adapted from the standard NF ISO 5794-1, Annex E of June 2010 [multipoint volumetric method (5 points) - gas: nitrogen - degassing under vacuum: one hour at 160°C - relative pressure range w / in: 0.05 to 0.17],

[0097] For inorganic fillers such as silica, for example, the CTAB specific surface area values ​​were determined according to the NF ISO 5794-1 standard, Annex G of June 2010. The process is based on the adsorption of CTAB (N-hexadecyl-N,N,N-trimethylammonium bromide) on the "external" surface of the reinforcing filler.

[0098] To couple silica to the SBRs of the elastomer matrix, a coupling agent (or bonding agent) with at least two functional groups can be used in a well-known manner. This agent is designed to ensure sufficient chemical and / or physical interaction between the silica (surface of its particles) and an SBR. Organosilanes or polyorganosiloxanes with at least two functional groups are particularly useful. "Two functional groups" refers to a compound possessing a first functional group capable of interacting with silica and a second functional group capable of interacting with an SBR. For example, such a two-functional compound might include a first functional group comprising a silicon atom, which is capable of interacting with the hydroxyl groups of silica, and a second functional group comprising a sulfur atom, which is capable of interacting with an SBR.Preferably, organosilanes are chosen from the group consisting of polysulfide organosilanes (symmetric or asymmetric) such as bis(3-triethoxysilylpropyl) tetrasulfide, abbreviated TESPT and marketed under the name "Si69" by Evonik, or bis-(triethoxysilylpropyl) disulfide, abbreviated TESPD and marketed under the name "Si75" by Evonik; polyorganosiloxanes; mercaptosilanes; and blocked mercaptosilanes, such as S-(3-(triethoxysilyl)propyl) octanethioate, marketed by Momentive under the name "NXT Silane". More preferably, the organosilane is a polysulfide organosilane.

[0099] Of course, mixtures of the coupling agents described above could also be used.

[0100] The coupling agent content in the composition of the invention is advantageously less than or equal to 30 parts per liter, it being understood that it is generally desirable to use as little as possible. Typically, the coupling agent content represents 0.5% to 15% by weight relative to the amount of silica. This percentage is easily adjusted by a person skilled in the art according to the amount of silica used in the composition of the invention.

[0101] Plasticizing System

[0102] The tire rubber composition according to the invention is based on a plasticizing system comprising at least one hydrocarbon plasticizing resin, which resin is based on a cyclic monomer selected from the group consisting of a distillation cut from a petroleum refinery stream, C4, C5, and C6 cyclic olefins, and mixtures thereof, and which hydrocarbon resin has an aromatic proton content (H₂Ar, expressed in mol%), a glass transition temperature (Tg, expressed in °C), and a number-average molecular weight (Mn, expressed in g / mol) such that

[0103] (1) H Ar > 6 mol

[0104] (2) Tg > 95 - 2.2

[0105] (3) Tg > -53 + (0

[0106] (4) 250 g / mol < Mn < 600 g / mol.

[0107] The term "hydrocarbon resin based on" refers to the polymer resulting from the polymerization of cyclic monomers and / or aromatic monomers, these monomers being replaced by their corresponding units in the polymer after the polymerization reaction. Such polymerization of cyclic and / or aromatic monomers yields hydrocarbon resins comprising the corresponding cyclic and / or aromatic units.

[0108] As used here, the term "cyclic monomer" refers to a distillation cut and / or a synthetic mixture of C5 and C6 cyclic olefins, diolefins, dimers, codimers, and trimers. More specifically, cyclic monomers include, but are not limited to, cyclopentene, cyclopentadiene ("CPD"), dicyclopentadiene ("DCPD"), cyclohexene, 1,3-cyclohexadiene, 1,4-cyclohexadiene, methylcyclopentadiene ("MCPD"), di(methylcyclopentadiene) ("MCPD dimer"), and codimers of CPD and / or MCPD with C4 cyclics such as butadienes, and C5 cyclics such as piperylene. An example of a cyclic monomer is cyclopentadiene. Cyclic monomers may be substituted. Dicyclopentadiene can be in endo or exo form. Substituted cyclic monomers include cyclopentadienes and dicyclopentadienes substituted with a linear, branched or cyclic alkyl group in Cl to C40.According to one aspect, the substituted cyclic monomer may have one or more methyl groups. According to one aspect, the cyclic monomers are chosen from the group comprising: cyclopentadiene, cyclopentadiene dimer, cyclopentadiene-C4 codimer, cyclopentadiene-C5 codimer, cyclopentadiene-methylcyclopentadiene codimer, methylcyclopentadiene-C4 codimer, methylcyclopentadiene-C5 codimer, methylcyclopentadiene dimer, cyclopentadiene and methylcyclopentadiene, trimers and cotrimers, and / or mixtures thereof.

[0109] In one aspect, the cyclic monomer is chosen from the group consisting of cyclopentene, cyclopentadiene, dicyclopentadiene, cyclohexene, 1,3-cyclohexadiene, 1,4-cyclohexadiene, methylcyclopentadiene, di(methylcyclopentadiene), and mixtures thereof. According to another aspect, the cyclic monomer is chosen from the group consisting of dicyclopentadiene, cyclopentadiene, and methylcyclopentadiene. According to yet another aspect, the cyclic monomer is cyclopentadiene.

[0110] In one aspect, the hydrocarbon resin comprises the cyclic monomer in an amount ranging from 10% by weight to 90% by weight. In another aspect, the hydrocarbon resin comprises the cyclic monomer in an amount ranging from 25% by weight to 80% by weight.

[0111] In one aspect, the hydrocarbon resin comprises dicyclopentadiene, cyclopentadiene, and / or methylcyclopentadiene in an amount ranging from 10% to 90% by weight. In another aspect, the hydrocarbon resin comprises dicyclopentadiene, cyclopentadiene, and / or methylcyclopentadiene in an amount ranging from 25% to 80% by weight. In another aspect, the hydrocarbon resin comprises methylcyclopentadiene in an amount ranging from 0.1% to 15% by weight. In another aspect, the hydrocarbon resin comprises methylcyclopentadiene in an amount ranging from 0.1% to 5% by weight.

[0112] The hydrocarbon resin in question comprises one or more cyclic monomers used to prepare one or more complex copolymers as described herein. The composition of the complex copolymer can be controlled by the type and quantity of monomer included in the resin, i.e., the copolymer microstructure. However, the placement of the monomers within the polymer chain is random, further complicating the polymer microstructure.

[0113] In one aspect, the hydrocarbon resin further comprises an aromatic monomer. According to one aspect, the aromatic monomer is selected from the group consisting of olefin-aromatic compounds, aromatic distillation cuts, and mixtures thereof.

[0114] Depending on one aspect, the hydrocarbon resin comprises the aromatic monomer in an amount ranging from 10% by weight to 90% by weight. Depending on another aspect, the hydrocarbon resin comprises the aromatic monomer in an amount ranging from 20% by weight to 75% by weight.

[0115] According to one aspect, the aromatic monomer is an aromatic distillation cut. According to another aspect, the hydrocarbon resin comprises an aromatic distillation cut from a petroleum refinery stream, such as a stream obtained by steam cracking, and then separating the boiling fraction in the range of 135 °C to 220 °C by fractional distillation. According to another aspect, the aromatic distillation cut component comprises at least one element of styrene, alkyl-substituted derivatives of styrene, indene, alkyl-substituted derivatives of indene, and mixtures thereof. According to one aspect, the aromatic distillation cut component comprises 4% by weight to 7% by weight of styrene, 20% by weight to 30% by weight of alkyl-substituted derivatives of styrene, 10% by weight to 25% by weight of indene, 5% by weight to 10% by weight of alkyl-substituted derivatives of indene and 35% by weight to 45% by weight of non-reactive aromatics.

[0116] In one aspect, the aromatic monomer comprises an olefinic aromatic compound selected from the group consisting of indene derivatives, vinylaromatic compounds, and mixtures thereof.

[0117] In one aspect, the aromatic monomer comprises an indene derivative represented by the formula (O- in which RI and R2 independently represent a hydrogen atom, an alkyl group, an alkenyl group, a cycloalkyl group, an aryl group, or an arylalkyl group. For example, such compounds may be 1H-indene; 1-methyl-1H-indene; alkylindene; 5-(2-methylbut-2-enyl)-1H-indene; 5,6,7,8-tetrahydro-1H-cyclopentanaphthalene; 4Hindene-5butan-1H or its derivatives.

[0118] In one aspect, the aromatic monomer comprises a vinylaromatic compound represented by formula (II). in which R3 and R4 independently represent a hydrogen atom, an alkyl group, an alkenyl group, a cycloalkyl group, an aryl group, or an arylalkyl group. Alpha-methylstyrene or substituted alpha-methylstyrenes having one or more substituents on the aromatic ring are suitable, particularly when the substituents are chosen from alkyl, cycloalkyl, aryl radicals, or a combination thereof, each having one to eight carbon atoms per substituent. Non-limiting examples include alpha-methylstyrene, alpha-methyl-4-butylstyrene, alpha-methyl-3,5-di-t-benzylstyrene, alpha-methyl-3,4,5-trimethylstyrene, alpha-methyl-4-benzylstyrene, alpha-methyl-4-chlorohexylstyrene, and / or mixtures thereof. These hydrocarbon resins can be prepared using different methodologies.For example, the thermal polymerization of cyclic feed streams can be used in combination with or without aromatic olefins, substituted benzene, and aromatic distillation cuts. As described in the examples below, different resins were prepared to achieve a desired molecular weight and a specific stickiness point. Specifically, Tables 2A, 2B, 3A, and 3B below describe the feed streams, polymerization conditions, and final properties of these hydrocarbon resins.

[0119] Incompatibility with base polymers can limit the applications of high-Tg resins where low molecular weight and ease of processing are desirable. These hydrocarbon resins overcome this drawback thanks to a novel combination of Tg and Mn.

[0120] Furthermore, hydrocarbon resins are defined by their aromatic proton content ("H Ar"), in addition to their glass transition temperature ("Tg") and number-average molecular weight ("Mn"). More specifically, the hydrocarbon resin according to the invention has an aromatic proton content ("H Ar"), expressed as a percentage, greater than 6% by mole, preferably between 6% by mole and 25% by mole, and more preferably from 12% by mole to 19% by mole.

[0121] More specifically, these hydrocarbon resins are defined as:

[0122] - Tg > 95 - 2.2

[0123] - Tg > -53 + (0,

[0124] - 250 g / mol < Mn < 600 g / mol, preferably 300 g / mol < Mn < 450 g / mol, preferably even 350 g / mol < Mn < 420 g / mol where Tg is the glass transition temperature expressed in °C of the resin, H Ar represents the aromatic proton content in the resin and Mn represents the number-average molecular weight of the resin.

[0125] According to one aspect, the hydrocarbon resin has a glass transition temperature (Tg) ranging from 70 °C to 95 °C, preferably from 70 °C to 90 °C.

[0126] In one aspect, the hydrocarbon resin has an average molecular weight z (Mz) of less than 1000 g / mol.

[0127] Depending on one aspect, the hydrocarbon resin exhibits at least one and preferably all of the following additional characteristics:

[0128] - an average number molecular mass (Mn) of 300 g / mol < Mn < 450 g / mol, preferably ranging from 350 to 420 g / mol,

[0129] - a glass transition temperature (Tg) represented by Tg > 100 - 2.2* (H Ar),

[0130] - a glass transition temperature (Tg) represented by Tg > -32 + (0.265*Mn).

[0131] As described above, the tire rubber compositions according to the invention comprise one or more of the present hydrocarbon resins.

[0132] The hydrocarbon resin content in the rubber compound can range from 15% to 150%, 25% to 120%, 40% to 115%, 50% to 110%, and 65% to 110%. Below 15% of this hydrocarbon resin, its effect becomes insufficient, and the rubber compound may exhibit adhesion problems. Above 15%, the compound may present manufacturing difficulties in terms of incorporating the hydrocarbon resin. The Tg of the terpene resin is measured by Differential Scanning Calorimetry (DSC) according to ASTM D3418-12.

[0133] The macrostructure (Mw, Mn and IP) of the terpene resin is determined by size exclusion chromatography (SEC) based on ISO 16014 (Determination of average molecular mass and molecular mass distribution of polymers using size exclusion chromatography), ASTM D5296 (Molecular Weight Averages and molecular weight distribution of polystyrene by High performance size exclusion chromatography), and DIN 55672 (size exclusion chromatography): tetrahydrofuran solvent; temperature 35°C; concentration 1 g / l; flow rate 1 ml / min; solution filtered on a 0.45 pm porosity filter before injection; Moore calibration with polystyrene standards; set of 3 "WATERS" columns in series ("STYRAGEL" HR4E, HR1 and HR0.5); detection by differential refractometer ("WATERS 2410") and its associated operating software ("WATERS EMPOWER").

[0134] The plasticizing system according to the invention may comprise, in addition to the hydrocarbon resin, at least one plasticizing oil, a liquid plasticizer, or at least one hydrocarbon resin different from that described above. These plasticizers are well known to those skilled in the art and are commercially available.

[0135] The total percentage of plasticizers constituting the plasticizing system is greater than or equal to 25 parts per million, preferably within a range of 25 to 150 parts per million.

[0136] Crosslinking system

[0137] The crosslinking system can be any type of system known to those skilled in the art in the field of tire rubber compounds. It may, in particular, be sulfur-based, and / or peroxide-based, and / or bismaleimide-based.

[0138] Preferably, the crosslinking system is sulfur-based; this is then referred to as a vulcanization system. The sulfur can be supplied in any form, including molecular sulfur or a sulfur-donating agent. At least one vulcanization accelerator is also preferably present, and optionally, various known vulcanization activators such as zinc oxide, stearic acid, or equivalent compounds such as stearic acid salts and transition metal salts, guanidine derivatives (particularly diphenylguanidine), or known vulcanization retarders may be used.

[0139] Sulfur is used at a preferential rate of 0.2 to 10 parts per annum, more preferably from 0.3 to 5 parts per annum. The vulcanizing accelerator or accelerator mixture is used at a preferential rate of 0.5 to 10 parts per annum, more preferably from 0.5 to 5 parts per annum.

[0140] Any compound capable of acting as a vulcanization accelerator for diene elastomers in the presence of sulfur can be used as an accelerator, including thiazole-type accelerators and their derivatives, sulfenamide-type accelerators, thiurams, dithiocarbamates, dithiophosphates, thioureas and xanthates. Examples of such accelerators include the following compounds: 2-mercaptobenzothiazyl disulfide (abbreviated "MBTS"), N-cyclohexyl-2-benzothiazyl sulfenamide ("CBS"), N,N-dicyclohexyl-2-benzothiazyl sulfenamide ("DCBS"), N-ter-butyl-2-benzothiazyl sulfenamide ("TBBS"), N-ter-butyl-2-benzothiazyl sulfenimide ("TBSI"), tetrabenzylthiuram disulfide ("TBZTD"), zinc dibenzyldithiocarbamate ("ZBEC") and mixtures of these compounds.

[0141] Additives

[0142] The rubber composition according to the invention may optionally also include all or some of the usual additives commonly used in elastomer compositions for tires, pigments, protective agents such as anti-ozone waxes, chemical anti-ozonants, antioxidants, anti-fatigue agents, reinforcing resins...

[0143] Of course, the compositions according to the invention can be used alone or in cutting (i.e., in mixing) with any other rubber composition usable for the manufacture of rubber articles, in particular semi-finished articles for tires or tires.

[0144] It goes without saying that the invention relates to the rubber compositions described above both in the so-called "raw" or non-crosslinked state (i.e., before cooking) and in the so-called "cooked" or crosslinked state, or even vulcanized (i.e., after crosslinking or vulcanization).

[0145] Preparation of the rubber compound

[0146] The composition according to the invention can be manufactured in suitable mixers, using two successive preparation phases well known to those skilled in the art:

[0147] - a first thermomechanical working or mixing phase (the so-called "non-productive" phase), which can be carried out in a single thermomechanical step during which all the necessary constituents, including the elastomeric matrix, the reinforcing filler, the plasticizing system, and any other miscellaneous additives, with the exception of the crosslinking system, are introduced into a suitable mixer such as a standard internal mixer (for example, of the 'Banbury' type). The incorporation of the filler into the elastomer can be carried out in one or more stages by thermomechanical mixing.Where the filler is already fully or partially incorporated into the elastomer as a masterbatch, as described, for example, in applications WO 97 / 36724 or WO 99 / 16600, the masterbatch is mixed directly. If necessary, other elastomers or fillers present in the composition that are not in masterbatch form are also incorporated, along with any other miscellaneous additives other than the crosslinking system. The non-productive phase can be carried out at high temperature, up to a maximum temperature of 110°C to 200°C, preferably between 130°C and 185°C, for a duration generally ranging from 2 to 10 minutes.

[0148] - a second mechanical working phase (the so-called "productive" phase), which is carried out in an external mixer such as a roller mixer, after cooling the mixture obtained during the first non-productive phase to a lower temperature, typically below 120°C, for example between 40°C and 100°C. The crosslinking system is then incorporated, and the whole is then mixed for a few minutes, for example between 5 and 15 min.

[0149] Such phases are well known to those skilled in the art.

[0150] The resulting final composition is then calendered, for example, into a sheet or plate, particularly for laboratory characterization, or extruded (or co-extruded with another rubber compound) into a semi-finished product (or profile) of rubber usable in a tire, for example as a tread. These products can then be used for tire manufacturing, according to techniques known to those skilled in the art.

[0151] The composition can be either in its raw state (before crosslinking or vulcanization), or in its cooked state (after crosslinking or vulcanization), and can be a semi-finished product that can be used in a tire.

[0152] Crosslinking (or curing), where applicable vulcanization, is carried out in a known manner at a temperature generally ranging from 130°C to 200°C, for a sufficient time which can vary for example between 5 and 90 min depending in particular on the curing temperature, the crosslinking system adopted and the crosslinking kinetics of the composition considered.

[0153] Semi-finished product and tire

[0154] The rubber compound of the tire according to the invention exhibits improved mechanical properties, notably an improved tensile strength. A tire with such a compound in its tread promises improved tire durability.

[0155] Preferably, the composition described above is used in the tread of the tire according to the invention.

[0156] EXAMPLES

[0157] The following examples illustrate the invention without, however, limiting it.

[0158] Description of the resin

[0159] The resin according to the invention is a modified aromatic (Indene) hydrogenated DCPD resin manufactured according to the process described in WO2022161742. It has a Tg of 88°C, a Mn of 389 g / mol and an H Ar content of 16%.

[0160] Manufacturing of rubber compounds

[0161] For the following tests, the compositions are prepared as follows: all components, except for the vulcanization system, are introduced into an internal mixer filled to 70% capacity and with an initial tank temperature of approximately 70°C. A thermomechanical process (non-productive phase) is then carried out in a single stage (total mixing time of approximately 5 minutes) until a maximum "drop" temperature of approximately 165°C is reached.

[0162] The mixture thus obtained is collected, cooled, and then the vulcanization system (sulfur and accelerator) is added to an external mixer (homo-finisher) at 70°C, mixing everything (productive phase) for about 5 to 6 min.

[0163] The resulting compositions are then calendered, either into plates (2 to 3 mm thick) or thin sheets of rubber, to measure their physical and mechanical properties after curing. Tests

[0164] These tests are intended to demonstrate the excellent level of tensile strength of the rubber compositions according to the invention comprising a specific elastomer matrix and a specific plasticizing system comprising a particular hydrocarbon resin compared to a non-conforming rubber composition whose elastomer matrix does not have the same composition.

[0165] Table 1 presents the characteristics of the compositions tested.

[0166] Table 1

[0167] (1) SBR functionalized with 3-(N,N-dimethylaminopropyl)trimethoxysilane prepared according to W02018 / 115722A1, with 27% styrene motif and 24% 1,2 motif of the butadiene part (Tg = -48°C);

[0168] (2) SBR functionalized with 3-(N,N-dimethylaminopropyl)trimethoxysilane prepared according to W02018 / 115722A1, with 2.1% styrene motif and 12.7% 1,2 motif of the butadiene part (Tg = -88°C);

[0169] (3) Modified aromatic DCPD resin (Indene) hydrogenated, Tg=88°C, Mn=389g / mol;

[0170] (4) ASTM N234 grade carbon black marketed by Cabot;

[0171] (5) Silica “Zeosil 1165 MP” from the Solvay company type “HDS”; its specific surface area BET is 160 m2 / g;

[0172] (6) N-(l,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine (Santoflex 6-PPD) from Flexsys;

[0173] (7) Diphenylguanidine “Perkacit DPG” from the company Flexsys;

[0174] (8) Coupling agent silane polysulfide bistriethoxysilyl propyl)tetrasulfide marketed under the reference "Si69" by the company Evonik - Degussa;

[0175] (9) Stearine “Pristerene 4931” from the company Uniqema;

[0176] (10) 2,2,4-trimethyl-1,2-dihydroquinoline (TMQ);

[0177] (11) Industrial grade zinc oxide - Umicore company;

[0178] (12) N-cyclohexyl-2-benzothiazol-sulfenamide (“Santocure CBS” from Flexsys);

[0179] (13) Solid sulfur. Measurements and tests used:

[0180] Tensile test

[0181] These tensile tests determine the elastic stresses and fracture properties. Unless otherwise specified, they are carried out in accordance with the French standard NF T 46-002 of September 1988. Processing the tensile test data also allows for plotting the modulus curve as a function of elongation.

[0182] The breaking stresses (in MPa) are measured at 23°C ± 2°C, according to standard NF T 46-002.

[0183] The tensile strength measurement is a descriptor of a material's tensile performance. The value, expressed as a base of 100, is calculated using the formula: (Tension strength of the sample / Tensile strength of the control) * 100. Therefore, a value higher than the control indicates an increase in tensile strength.

[0184] Results

[0185] Table 2 presents the results of the measurements carried out.

[0186] Table 2

[0187] It is noted that the control composition T1, comprising an elastomer matrix not conforming to the invention, serves as a baseline (100) for comparing the performance of compositions conforming to the invention. It is noted that compositions C1, C2, and C3 according to the invention unexpectedly improve the tensile strength at 23°C and therefore the mechanical properties of the compositions. This suggests an improvement in the durability of tires containing such compositions, particularly when used in the tread.

Claims

DEMANDS 1. Tire comprising a rubber composition based on at least: - an elastomeric matrix comprising a styrene-butadiene copolymer A with Tg(A) varying in the range of -100°C to -60°C and a styrene-butadiene copolymer B with Tg(B) varying in the range of -70°C to -40°C, with 10°C <Tg(B)-Tg(A)< 60°C, la Tg étant mesurée selon la norme ASTM D3418-12, - a reinforcing filler comprising silica, - a vulcanization system and - a plasticizing system comprising a hydrocarbon resin, which resin is based on a cyclic monomer selected from the group consisting of a distillation cut from a petroleum refinery stream, C4, C5 and C6 cyclic olefins and mixtures thereof, and which hydrocarbon resin has an aromatic proton content (H₂Ar, expressed in mol%), a glass transition temperature (Tg, expressed in °C) and a number-average molecular weight (Mn, expressed in g / mol) such that (1) H Ar > 6 mol (2) Tg > 95 - 2.2 (3) Tg > -53 + (0, (4) 250 g / mol < Mn < 600 g / mol.

2. Tyre according to claim 1, wherein the styrene-butadiene copolymer B has a Tg(B) varying in a range from -60°C to -40°C.

3. Tire according to any one of the preceding claims, wherein the styrene-butadiene copolymer (A) has a Tg(A) varying in a range from -90°C to -70°C.

4. Tire according to any one of the preceding claims, wherein the elastomer matrix comprises from 20 pc to 70 pc of styrene-butadiene copolymer (B), preferably from 30 pc to 70 pc.

5. Tire according to any one of the preceding claims, wherein the elastomer matrix comprises from 20 pc to 70 pc of styrene-butadiene copolymer (A), preferably from 30 pc to 70 pc.

6. Tire according to any one of the preceding claims, wherein at least one of the styrene-butadiene copolymers (A) and (B), preferably both, is functionalized and carries at least one silanol or alkoxysilyl -SiOR function, R representing a C1-C8 alkyl radical, preferably C1-C4.

7. Tire according to any one of the preceding claims, wherein at least one of the styrene-butadiene copolymers (A) and (B), preferably both, is functionalized and carries at least one silanol or alkoxysilyl -SiOR function, R representing a C1-C8 alkyl radical, preferably C1-C4 and another function chosen from primary, protected or unprotected, secondary, protected or unprotected, or tertiary amine functions of formula -NR'a, each of the R's independently representing a hydrogen atom or an alkyl radical in C1-C8, preferably in C1-C4, the glycidyloxy and epoxy functions, and the thiol function -SH, protected or unprotected.

8. Tire according to any one of the preceding claims, wherein at least one of the styrene-butadiene copolymers (A) and (B), preferably both, is functionalized and bears at least one >SiOR(Sp-NR'3) group, the Si atom being in the main chain of the copolymer, R representing a C1-C8 alkyl radical, preferably C1-C4, or a hydrogen atom, R' representing a C1-C4 alkyl radical, and Sp being a linear divalent aliphatic group in C1-C6, preferably again C1-C4, the symbol ">" indicates that the silicon atom is bonded to 2 carbon atoms of the main polymer chain.

9. Tire according to any one of the preceding claims, wherein the hydrocarbon resin is further characterized by an aromatic proton content of 12 mol% < H Ar < 19 mol%.

10. Tire according to any one of the preceding claims, wherein the hydrocarbon resin comprises the cyclic monomer in an amount from 10% by weight to 90% by weight, preferably in an amount from 25% by weight to 80% by weight, of the total weight of the resin, wherein the cyclic monomer is selected from the group consisting of cyclopentene, cyclopentadiene, dicyclopentadiene, cyclohexene, 1,3-cyclohexadiene, 1,4-cyclohexadiene, methylcyclopentadiene, di(methylcyclopentadiene) and mixtures thereof.

11. Tire according to any one of the preceding claims, wherein the hydrocarbon resin comprises methylcyclopentadiene in an amount from 0.1% by weight to 15% by weight, preferably from 0.1% by weight to 5% by weight.

12. Tire according to any one of the preceding claims, wherein the resin is further based on an aromatic monomer in an amount from 10% by weight to 90% by weight, preferably in an amount from 20% by weight to 75% by weight of the weight of the resin, which aromatic monomer is selected from the group consisting of aromatic olefin compounds, aromatic distillation cuts and mixtures thereof.

13. Tire according to any one of the preceding claims, wherein the hydrocarbon resin has at least one and preferably all of the following additional characteristics: - an average molecular mass by number (Mn) ranging from 300 to 450 g / mol, - a glass transition temperature (Tg) represented by Tg > 100 - 2.2* (H Ar), - a glass transition temperature (Tg) represented by Tg > -32 + (0.265*Mn).

14. A tire according to any one of the preceding claims, wherein the content of said hydrocarbon resin is in the range of 15 to 150 parts per annum, and preferably from 25 to 120 parts per annum.

15. A tire according to any one of the preceding claims, wherein the silica content is in the range of 40 to 160 parts per annum.

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