Elastomeric composition

Abstract

The present invention relates to a rubber composition based on: 20 to 100 phr of a copolymer of ethylene, a first 1,3-diene and a second 1,3-diene of formula CH2=CR-CH=CH2, the first 1,3-diene being 1,3-butadiene, isoprene or a mixture thereof, wherein the symbol R represents a hydrocarbon chain having 3 to 20 carbon atoms, the ethylene units in the copolymer representing more than 50 mol% of the monomer units of the copolymer, the diene unit weight content of the diene elastomer being greater than 50%, 10 to 100 phr of a plasticizing system, a reinforcing filler and a crosslinking system, the plasticizing system comprising at least one plasticizing resin having a glass transition temperature higher than 20°C and / or at least one plasticizer which is liquid at 23°C. The present invention also relates to an elastomeric laminate and a rubber article, in particular a pneumatic or non-pneumatic tire, comprising such a composition.

Description

Technical Field

[0001] The field of this invention is the field of rubber compositions (particularly compositions intended for use in tires) containing highly saturated diene elastomers. Background Technology

[0002] A tire typically includes two beads, a crown, and two sidewalls. The beads are designed to contact the rim, the crown consists of at least one crown reinforcement and a tread, and the tire is reinforced by a carcass reinforcement anchored in the two beads.

[0003] In conventional tire manufacturing, the various components—the tread, carcass reinforcement, bead, and sidewall—are assembled to form a pneumatic tire. Following assembly is the tire shaping process to give the components a tortuous shape, followed by a curing step in a press.

[0004] When assembling a tire, the tread is located radially outside the crown reinforcement and is typically separated from the crown reinforcement by the tread substructure. The sidewall itself is an elastomeric layer located outside the carcass reinforcement relative to the tire's interior and between the crown and the bead, thus completely or partially covering the area of ​​the carcass reinforcement extending from the crown to the bead.

[0005] The tread, designed to contact the ground when rolling, must possess very specific properties, particularly good grip on both dry and wet surfaces, low rolling resistance, and good abrasion resistance. As the tire rolls, the tire sidewall itself undergoes cycles of deformation (e.g., bending); the rubber composition constituting the tire sidewall must have sufficient flexibility and not too high hysteresis, and must also have good resistance to physical attacks (e.g., road impacts) and chemical attacks (e.g., ozone exposure). Therefore, the composition of the tire tread and sidewall is made of very specific materials and differs from the tire layers (e.g., the tread base layer or carcass ply) located below the tread and sidewall, which are typically composed of compositions containing highly unsaturated diene elastomers (e.g., natural rubber) and reinforcing fillers (e.g., carbon black).

[0006] This difference in composition can lead to a decrease in the adhesive properties of the tire tread or sidewall to its respective adjacent layers.

[0007] Therefore, it remains important to develop compositions that have good properties relative to their intended location (e.g., tread or sidewall) while also having good adhesion to their respective adjacent layers (thus particularly improving the retention of the cured interface). Summary of the Invention

[0008] During further research, the applicant discovered that using copolymers of ethylene and two specific 1,3-dienes could further improve the adhesion of the composition to the diene composition.

[0009] Therefore, the first subject of this invention is a rubber composition based on:

[0010] A copolymer of at least one ethylene, a first 1,3-diene, and a second 1,3-diene of formula (I) from -20 phr to 100 phr, wherein the first 1,3-diene is 1,3-butadiene, isoprene, or a mixture thereof, and the ethylene units in the copolymer account for more than 50 mol% of the monomer units of the copolymer.

[0011] CH2=CR-CH=CH2(I)

[0012] The symbol R represents a hydrocarbon chain with 3 to 20 carbon atoms;

[0013] At least one diene elastomer from -0 phr to 80 phr, wherein the diene elastomer contains more than 50% by weight of diene units;

[0014] A plasticizing system ranging from -10 phr to 100 phr, wherein the plasticizing system comprises at least one plasticizer that is liquid at 23°C and / or at least one plasticizing resin with a glass transition temperature above 20°C.

[0015] -Reinforced fillers; and

[0016] - Crosslinking system.

[0017] Another subject of the invention is a laminate comprising at least two layers, a first layer consisting of the composition, and a rubber composition constituting the second layer based on a diene elastomer and a crosslinking system, wherein the diene elastomer contains more than 50% by weight diene units. Another subject of the invention is rubber articles comprising the composition or the laminate, and pneumatic or non-pneumatic tires. Detailed Implementation

[0018] I-Definition

[0019] The expression “based on” used to define the components of a catalytic system is understood to mean a mixture of these components or the reaction products between some or all of these components.

[0020] The statement “composition based” should be understood to mean that the composition comprises a mixture of various components used and / or in-situ reaction products, some of which are capable (and / or intended) to react with each other at least partially during the various manufacturing stages of the composition; therefore, the composition may be in a fully or partially crosslinked state or a non-crosslinked state.

[0021] "Elastomer matrix" is understood to mean all elastomers in the composition, including copolymers as defined below.

[0022] Unless otherwise stated, the content of units obtained by inserting monomers into copolymers is expressed as a molar percentage relative to all monomer units of the copolymer.

[0023] In the context of this invention, the expression "parts by weight / percentage of elastomer" (or phr) should be understood to mean parts by weight / percentage of elastomer. In laminates comprising multiple layers, the expression "parts by weight / percentage of elastomer" applies to the rubber composition considered and constituting the layers.

[0024] Furthermore, any numerical interval expressed as "between a and b" represents a range of values ​​greater than a and less than b (i.e., excluding the limits a and b), while any numerical interval expressed as "from a to b" means a range of values ​​from a to b (i.e., including the strict limits a and b). In this application, when a numerical interval is expressed as "from a to b," it is also preferable to express the interval expressed as "between a and b."

[0025] When referring to a "major" compound, for the purposes of this invention, it is understood to mean that the compound is dominant among compounds of the same type in the composition, i.e., the compound that constitutes the largest amount by weight among compounds of the same type. Thus, for example, a major elastomer is the elastomer that constitutes the largest weight relative to the total weight of elastomers in the composition. Similarly, a "major" filler is the filler that constitutes the largest weight among the fillers in the composition. For example, in a system containing only one elastomer, said elastomer is dominant for the purposes of this invention, and in a system containing two elastomers, the major elastomer constitutes more than half the weight of the elastomer. Conversely, a "minor" compound is a compound that does not constitute the largest weight fraction among compounds of the same type. Preferably, the term "major" is intended to mean present at a concentration greater than 50% by weight, preferably greater than 60%, 70%, 80%, or 90%, and more preferably, the "major" compound constitutes 100% by weight.

[0026] The compounds mentioned in the specification can be fossil-derived compounds or bio-based compounds. In the case of bio-based compounds, they can be partially or wholly derived from biomass or obtained from renewable raw materials derived from biomass. Similarly, the mentioned compounds can also be derived from the recycling of already used materials, i.e., they can be partially or wholly derived from recycling processes or obtained from raw materials that are themselves derived from recycling processes.

[0027] The values ​​of all glass transition temperatures “Tg” described in this application are measured by DSC (differential scanning calorimetry) in a known manner according to standard ASTM D3418 (1999).

[0028] II - Detailed Description of the Invention

[0029] II-1 Elastomer Matrix

[0030] The composition according to the invention is based on:

[0031] A copolymer of at least one ethylene, a first 1,3-diene, and a second 1,3-diene of formula (I) from -20 phr to 100 phr, wherein the first 1,3-diene is 1,3-butadiene, isoprene, or a mixture thereof, and the ethylene units in the copolymer account for more than 50 mol% of the monomer units of the copolymer.

[0032] CH2=CR-CH=CH2 (I)

[0033] The symbol R represents a hydrocarbon chain with 3 to 20 carbon atoms;

[0034] At least one diene elastomer from -0 phr to 80 phr, wherein the diene elastomer contains more than 50% by weight of diene units.

[0035] In this application, unless otherwise stated, for the sake of brevity, the term "copolymer" means "a copolymer of at least one ethylene, a first 1,3-diene and a second 1,3-diene of formula (I), wherein the first 1,3-diene is 1,3-butadiene, isoprene or a mixture thereof, wherein the ethylene units in the copolymer account for more than 50% of the units, CH2=CR-CH=CH2(I), and the symbol R represents a hydrocarbon chain having 3 to 20 carbon atoms."

[0036] Furthermore, unless otherwise stated, the content of units obtained by inserting monomers into copolymers is expressed as a molar percentage relative to all monomer units of the copolymer.

[0037] The first 1,3-diene is 1,3-butadiene, isoprene, or a mixture thereof (i.e., a mixture of 1,3-butadiene and isoprene). The first 1,3-diene is preferably 1,3-butadiene.

[0038] The 1,3-diene of formula (I) is a substituted 1,3-diene that can produce a 1,2 configuration unit represented by formula (1), a 3,4 configuration unit represented by formula (2), and a 1,4 configuration unit (the trans form of which is represented by formula (3) below).

[0039]

[0040] As is well known, the ethylene unit is a unit of the -(CH2-CH2)- part.

[0041] The copolymer used for the purposes of this invention is a copolymer of ethylene, a first 1,3-diene, and a second 1,3-diene of formula (I), wherein the first 1,3-diene is 1,3-butadiene, isoprene, or a mixture thereof, which means that the monomeric unit of the copolymer is a unit produced by the polymerization of ethylene, the first 1,3-diene, and the second 1,3-diene of formula (I). According to the invention, the second 1,3-diene may be only one compound (i.e., only one 1,3-diene of formula (I)), or it may be a mixture of 1,3-dienes of formula (I) (the 1,3-dienes in the mixture are distinguished from each other by the group represented by the symbol R).

[0042] The copolymer used for the purposes of this invention is advantageously a random copolymer according to any embodiment of the invention. More advantageously, the copolymer is a random polymer according to any embodiment of the invention.

[0043] In formula (I) of 1,3-diene, the symbol R represents an unsaturated hydrocarbon chain having 3 to 20 carbon atoms. Preferably, the symbol R represents a hydrocarbon chain having 6 to 16 carbon atoms.

[0044] The second 1,3-diene can be a single compound (i.e., only one 1,3-diene of formula (I)) or a mixture of 1,3-dienes of formula (I) (the 1,3-dienes in the mixture are distinguished from each other by the group represented by the symbol R).

[0045] The hydrocarbon chain represented by the symbol R can be a saturated chain or an unsaturated chain. Preferably, the symbol R represents an aliphatic chain, in which case, in formula (I) of the 1,3-diene, the hydrocarbon chain represented by the symbol R is an aliphatic hydrocarbon chain. It can be a linear chain or a branched chain, in which case, the symbol R represents a linear chain or a branched chain. Preferably, the hydrocarbon chain is acyclic, in which case, the symbol R represents an acyclic chain. More preferably, the symbol R represents an unsaturated and branched acyclic hydrocarbon chain. Thus, the hydrocarbon chain represented by the symbol R is advantageously an unsaturated and branched acyclic chain containing 3 to 20 carbon atoms, particularly 6 to 16 carbon atoms. Very advantageously, the 1,3-diene is myrcene, β-farnesene, or a mixture of myrcene and β-farnesene.

[0046] Preferably, the copolymer contains ethylene units at a concentration between 50 mol% and 95 mol% of the monomer units of the copolymer, i.e., between 50 mol% and 95 mol% of the ethylene units and 1,3-diene units. Very preferably, the copolymer contains ethylene units at a concentration of 60 mol% to 90 mol% of the monomer units of the copolymer, more preferably 70 mol% to 85 mol%.

[0047] Advantageously, the copolymer contains a first 1,3-diene unit between 1 mol% and 49 mol% of the monomer units of the copolymer, preferably between 4 mol% and 29 mol%, and more preferably between 4 mol% and 25 mol%.

[0048] Advantageously, the copolymer contains 1,3-diene units of formula (I) in a concentration between 1 mol% and 50 mol% of the monomer units of the copolymer, preferably between 1 mol% and 30 mol%, and more preferably between 5 mol% and 30 mol%.

[0049] According to one embodiment of the invention, the copolymer comprises more than 60 mol% to 90 mol% of ethylene units and at most 20 mol%, preferably at most 15 mol% of a second 1,3-diene unit. According to this embodiment of the invention, the copolymer preferably comprises less than 30 mol% of a first 1,3-diene unit, or preferably less than 20 mol% of a first 1,3-diene unit.

[0050] According to another embodiment of the invention, the copolymer comprises 70 mol% to 90 mol% of ethylene units and up to 20 mol%, preferably up to 15 mol% of a second 1,3-diene unit. According to this embodiment of the invention, the copolymer preferably comprises less than 20 mol% of a first 1,3-diene unit.

[0051] According to another embodiment of the invention, the copolymer comprises more than 60 mol% to 85 mol% of ethylene units and at most 20 mol%, preferably at most 15 mol% of a second 1,3-diene unit. According to this embodiment of the invention, the copolymer preferably comprises less than 30 mol% of a first 1,3-diene unit, or preferably less than 20 mol% of a first 1,3-diene unit.

[0052] According to another embodiment of the invention, the copolymer comprises 70 mol% to 85 mol% of ethylene units and up to 20 mol%, preferably up to 15 mol% of a second 1,3-diene unit. According to this embodiment of the invention, the copolymer preferably comprises less than 20 mol% of a first 1,3-diene unit.

[0053] According to any embodiment of the invention, the copolymer preferably contains less than 80 mol% of ethylene units. According to any embodiment of the invention, the copolymer preferably contains at least 1 mol% of a second 1,3-diene unit, more preferably at least 5 mol% of a second 1,3-diene unit.

[0054] According to a particular embodiment of the invention, particularly when the first 1,3-diene is 1,3-butadiene or a mixture of 1,3-butadiene and isoprene, the copolymer also comprises units of the 1,2-cyclohexanediyl moiety. The presence of these cyclic structures in the copolymer results from very specific insertions of ethylene and 1,3-butadiene during polymerization. The content of the 1,2-cyclohexanediyl moiety units in the copolymer varies depending on the respective contents of ethylene and 1,3-butadiene in the copolymer. The copolymer preferably comprises less than 15 mol% of the 1,2-cyclohexanediyl moiety units.

[0055] Preferably, the glass transition temperature of the copolymer is below -35°C, more preferably between -90°C and -35°C, and even more preferably between -70°C and -35°C.

[0056] The copolymer can be prepared by a method comprising copolymerizing ethylene, a first 1,3-diene, and a second 1,3-diene of formula (I) in the presence of a catalytic system, said catalytic system being at least based on a metallocene of formula (II) and an organomagnesium compound of formula (III).

[0057] P(Cp 1 Cp 2 Nd(BH4) (1+y)- L y -N x (II)

[0058] MgR 1 R 2 (III)

[0059] in:

[0060] -Cp 1 and Cp 2 They may be the same or different, and are selected from cyclopentadienyl groups of formula C5H4, formula C 13 The unsubstituted and substituted fluorene groups of H8

[0061] -P bridges the two Cp values. 1 and Cp 2 The group represents ZR. 3 R 4 The group of the group, Z represents silicon or carbon atom, R 3 and R 4 They may be the same or different, and each represents an alkyl group containing 1 to 20 carbon atoms, preferably a methyl group.

[0062] -y is an integer equal to or greater than 0.

[0063] -x represents an integer equal to or greater than 0, or a non-integer.

[0064] -L indicates an alkali metal selected from lithium, sodium, and potassium.

[0065] -N indicates an ether molecule, preferably a diethyl ether or tetrahydrofuran.

[0066] -R 1 and R 2 They can be the same or different, and represent carbon-based.

[0067] As a substituted fluorene group, fluorene groups substituted with alkyl groups having 1 to 6 carbon atoms or aryl groups having 6 to 12 carbon atoms may be mentioned. The choice of group also depends on the availability of the corresponding molecule (substituted fluorene), since substituted fluorene is commercially available or readily synthesized.

[0068] As substituted fluorenyl groups, 2,7-di(tert-butyl)fluorenyl and 3,6-di(tert-butyl)fluorenyl are particularly noteworthy. Positions 2, 3, 6, and 7 represent the positions of carbon atoms in the ring shown in the diagram below, and position 9 corresponds to the carbon atom attached to bridge P.

[0069]

[0070] The catalytic system can be conventionally prepared by methods similar to those described in patent applications WO 2007054224 or WO 2007054223. For example, organomagnesium compounds and metallocenes are typically reacted in a hydrocarbon solvent at a temperature ranging from 20°C to 80°C for a period of time (between 5 and 60 minutes). The catalytic system is typically prepared in an aliphatic hydrocarbon solvent (e.g., methylcyclohexane) or an aromatic hydrocarbon solvent (e.g., toluene). Typically, after synthesis, the catalytic system is used in this form in methods for synthesizing copolymers according to the invention.

[0071] Alternatively, the catalytic system can be prepared by a method similar to that described in patent application WO 2017 / 093654 A1 or patent application WO2018 / 020122A1. According to this alternative, the catalytic system further comprises a preformed monomer selected from conjugated dienes, ethylene, or mixtures of ethylene and conjugated dienes, in which case the catalytic system is at least based on metallocene, organomagnesium compounds, and the preformed monomer. For example, the organomagnesium compound and metallocene are typically reacted in a hydrocarbon solvent at a temperature of 20°C to 80°C for 10 to 20 minutes to obtain a first reaction product, and then the preformed monomer selected from conjugated dienes, ethylene, or mixtures of ethylene and conjugated dienes is reacted with the first reaction product at a temperature of 40°C to 90°C for 1 to 12 hours. As the preformed monomer, the conjugated diene is preferably a 1,3-diene, such as 1,3-butadiene, isoprene, or a 1,3-diene of formula (I), particularly myrcene or β-farnesene. The resulting catalytic system can be used immediately in the method according to the invention, or stored in an inert atmosphere and then used in the method according to the invention.

[0072] Metallocenes used to prepare catalytic systems can be in the form of crystalline or amorphous powders, or in single-crystal form. Metallocenes can be in monomeric or dimer form, depending on the method of preparation, as described in patent applications WO 2007 / 054224 or WO 2007 / 054223. Metallocenes can be conventionally prepared by methods similar to those described in patent applications WO2007054224 or WO 2007054223, particularly under inert and anhydrous conditions by reacting an alkali metal salt of a ligand with a rare earth metal borohydride in a suitable solvent (e.g., an ether (e.g., diethyl ether or tetrahydrofuran) or any other solvent known to those skilled in the art). After the reaction, the metallocene is separated from the reaction by techniques known to those skilled in the art (e.g., filtration or precipitation in a second solvent). Finally, the metallocene is dried and separated in solid form.

[0073] Any synthesis, including metallocene synthesis and catalytic synthesis, in the presence of organometallic compounds is carried out under anhydrous conditions and an inert atmosphere. Typically, the reaction begins with anhydrous solvents and compounds under anhydrous nitrogen or argon.

[0074] The organomagnesium compounds used for the purposes of this invention have the formula MgR 1 R 2 , where R 1 and R 2 They can be the same or different, and both represent carbonyl groups. Carbonyl is understood to mean a group containing one or more carbon atoms. Preferably, R 1 and R 2It contains 2 to 10 carbon atoms. More preferably, R 1 and R 2 Each represents an alkyl group. Organomagnesia compounds are advantageously dialkylmagnesia compounds, more preferably butylethylmagnesium or butyloctylmagnesium, and even more preferably butyloctylmagnesium.

[0075] According to any embodiment of the invention, the molar ratio of the organomagnesia compound to the metal Nd constituting the metallocene is preferably in the range of 1 to 100, more preferably greater than or equal to 1 and less than 10. The numerical range of 1 to less than 10 is particularly advantageous for obtaining copolymers with high molar mass.

[0076] When the copolymer used for the purposes of this invention is a copolymer having a microstructure defined according to a first variant of the invention, it is prepared using a metallocene of formula (II) according to the method mentioned in this application, wherein Cp 1 and Cp 2 They may be the same or different, and are selected from substituted fluorene groups and formula C. 13 The unsubstituted fluorene group of H8. For this variant, the metallocene of the following formula (where the symbol Flu represents the formula C) is used. 13 The fluorene groups of H8 are particularly suitable: [{Me2SiFlu2Nd(μ-BH4)2Li(THF)}2], [Me2SiFlu2Nd(μ-BH4)2Li(THF)], [Me2SiFlu2Nd(μ-BH4)(THF)], [{Me2SiFlu2Nd(μ-BH4)(THF)}2], [Me2SiFlu2Nd(μ-BH4)].

[0077] Those skilled in the art also know how to adjust polymerization conditions and the concentrations of various reactants (components of the catalytic system, monomers) according to the equipment (apparatus, reactors) used to carry out polymerization and various chemical reactions. As is known to those skilled in the art, copolymerization, as well as the operation of monomers, catalytic systems, and polymerization solvents, is carried out under anhydrous conditions and an inert atmosphere. The polymerization solvent is typically an aliphatic hydrocarbon solvent or an aromatic hydrocarbon solvent.

[0078] Polymerization is preferably carried out continuously or batchwise in solution. The polymerization solvent can be an aromatic hydrocarbon solvent or an aliphatic hydrocarbon solvent. Examples of polymerization solvents that may be mentioned include toluene and methylcyclohexane. The monomer can be introduced into a reactor containing the polymerization solvent and a catalytic system, or conversely, the catalytic system can be introduced into a reactor containing the polymerization solvent and the monomer. Copolymerization is generally carried out under anhydrous conditions in the absence of oxygen and in the optional presence of an inert gas. The polymerization temperature is generally varied in the range of 30°C to 150°C, preferably from 30°C to 120°C. Preferably, the copolymerization is carried out at a constant ethylene pressure.

[0079] During the polymerization of ethylene, the first 1,3-diene, and the second 1,3-diene of formula (I) in a polymerization reactor, ethylene, the first 1,3-diene, and the second 1,3-diene of formula (I) can be continuously added to the polymerization reactor, in which case the polymerization reactor is a feed reactor. This embodiment is most particularly suitable for the synthesis of random copolymers.

[0080] Polymerization can be terminated by cooling the polymerization medium. The polymer can be recovered using conventional techniques known to those skilled in the art (e.g., precipitation, solvent evaporation under reduced pressure, or steam stripping).

[0081] The elastomeric matrix of the composition according to the invention may primarily comprise the copolymer. In this case, the content of the copolymer is advantageously in the range of greater than 50 phr to 100 phr, preferably 75 phr to 100 phr, more preferably 90 phr to 100 phr. The copolymer content may advantageously be 100 phr, i.e., the elastomeric matrix of the composition does not contain any elastomer other than the copolymer of ethylene, the first 1,3-diene, and the second 1,3-diene of formula (I). It should be understood that the copolymer may consist of a mixture of copolymers with different microstructures or macrostructures. When the elastomeric matrix of the composition primarily comprises the copolymer of ethylene, the first 1,3-diene, and the second 1,3-diene of formula (I), the content of the diene elastomer in the composition according to the invention, with a diene unit weight content greater than 50%, may be in the range of 0 phr to less than 50 phr, preferably 0 phr to 25 phr, more preferably 0 phr to 10 phr.

[0082] The elastomeric matrix of the composition according to the invention advantageously comprises a mixture of the copolymer and a diene elastomer with a weight content of at least one diene unit greater than 50%. Advantageously, the composition according to the invention comprises 20 phr to 90 phr, preferably 25 phr to 80 phr, more preferably 30 phr to 80 phr of the copolymer. It should be understood that the copolymer can consist of a mixture of copolymers with different microstructures or macrostructures. In this case, the content of the diene elastomer with a weight content of greater than 50% of the diene unit in the composition according to the invention is advantageously in the range of 10 phr to 80 phr, preferably 20 phr to 75 phr, more preferably 20 phr to 70 phr.

[0083] The diene unit is defined as a monomer unit formed by inserting a monomeric portion into the monomeric portion due to the polymerization of conjugated diene monomers or non-conjugated diene monomers, and the diene unit contains a carbon-carbon double bond.

[0084] Advantageously, the diene elastomers in which the weight content of the diene units of the compositions according to the invention is greater than 50% are selected from polybutadiene (BR), natural rubber (NR), synthetic polyisoprene (IR), butadiene copolymers, isoprene copolymers, and mixtures of these elastomers.

[0085] Preferably, the diene elastomer in which the weight content of the diene unit of the composition according to the invention is greater than 50% is selected from isoprene elastomers.

[0086] As is known, “isoprene elastomer” is understood to mean isoprene homopolymer or copolymer, in other words, diene elastomers selected from natural rubber (NR), synthetic polyisoprene (IR), various isoprene copolymers and mixtures of these elastomers.

[0087] Advantageously, the isoprene elastomer has a cis-1,4 bond weight content of at least 90% of the polyisoprene, preferably at least 98% of the polyisoprene.

[0088] Preferably, the polyisoprene is selected from natural rubber, synthetic polyisoprene, and mixtures thereof. More preferably, the polyisoprene is natural rubber.

[0089] II-2 Plasticizing System

[0090] The rubber composition according to the invention further comprises a plasticizing system of 10 phr to 100 phr, said plasticizing system comprising at least one plasticizer that is liquid at 23°C (referred to as "low Tg", that is, by definition, having a Tg below -20°C, preferably below -40°C) and / or a plasticizing resin with a glass transition temperature above 20°C (referred to as "high Tg") (also referred to as "plasticizing resin" in this application for the sake of brevity).

[0091] Advantageously, the content of the plasticizing system comprising at least one plasticizer that is liquid at 23°C and / or at least one plasticizing resin with a glass transition temperature higher than 20°C in the composition according to the invention is in the range of 35 phr to 100 phr, preferably 50 phr to 95 phr, more preferably 55 phr to 90 phr.

[0092] Advantageously, the plasticizing system of the composition according to the invention comprises at least one plasticizing resin with a glass transition temperature higher than 20°C, preferably, it simultaneously comprises a plasticizer that is liquid at 23°C and a plasticizing resin with a glass transition temperature higher than 20°C.

[0093] II-2.1 Plasticizing Resin

[0094] As defined by those skilled in the art, the term "resin" in this patent application is reserved for compounds that are solid at ambient temperature (23°C), which is different from liquid plasticizers (e.g., oils).

[0095] Plasticizing resins are polymers known to those skilled in the art, primarily based on carbon and hydrogen, but may also contain other types of atoms, and can be used particularly as plasticizers or tackifiers in polymer matrices. Plasticizing resins are generally substantially miscible (i.e., compatible) with the polymer composition intended to use the plasticizing resin at the concentrations used, thus acting as a true diluent. They have been described, for example, in the article entitled “Hydrocarbon Resins” by R. Mildenberg, M. Zander, and G. Collin (New York, VCH, 1997, ISBN 3-527-28617-9), Chapter 5 of which relates to their applications, particularly in the field of rubber tires (5.5. “Rubber Tires and Mechanical Goods”). They can be aliphatic, alicyclic, aromatic, hydrogenated aromatic, or aliphatic / aromatic types (i.e., based on aliphatic and / or aromatic monomers). They can be natural or synthetic, and can be petroleum-based or non-petroleum-based (if petroleum-based, they are also referred to as petroleum resins). Its Tg is preferably higher than 20°C (usually between 30°C and 95°C).

[0096] As is known, these plasticized resins can also be described as thermoplastic resins because they soften upon heating and are therefore moldable. They are also defined by their softening point. The softening point of a plasticized resin is typically about 50°C to 60°C higher than its Tg value. The softening point is measured according to standard ISO 4625 (ring and sphere method). The macrostructure (Mw, Mn, and PDI) is determined by size exclusion chromatography (SEC) as shown below.

[0097] As a reminder, SEC analysis, for example, involves separating macromolecules in solution based on their size using a column packed with a porous gel; molecules are separated based on their hydrodynamic volume, with the largest molecules eluting first. The sample to be analyzed is pre-dissolved simply in a suitable solvent (tetrahydrofuran) at a concentration of 1 g / L. The solution is then filtered through a filter with a porosity of 0.45 μm before being injected into the instrument. The instrument used is, for example, a Waters Alliance chromatogram according to the following conditions:

[0098] - The elution solvent is tetrahydrofuran;

[0099] -Temperature: 35℃;

[0100] -Concentration: 1 g / L;

[0101] -Flow rate: 1 ml / min;

[0102] -Injection volume: 100 μl;

[0103] - Molar calibration was performed using polystyrene standards;

[0104] - A series of three "Waters" columns (Styragel HR4E, Styragel HR1 and Styragel HR0.5);

[0105] - Detection is performed using a differential refractometer (e.g., WATERS2410) that can be equipped with operating software (e.g., Waters Millenium).

[0106] Molar calibration was performed using a series of commercial polystyrene standards with low PDI (less than 1.2), known molar masses, and covering the mass range to be analyzed. The weight-average molar mass (Mw), number-average molar mass (Mn), and polydispersity index (PDI = Mw / Mn) were derived from the recorded data (weight distribution curves of molar mass).

[0107] Therefore, all molar mass values ​​shown in this patent application are relative to a calibration curve generated from polystyrene standards.

[0108] According to a preferred embodiment of the invention, the plasticizing resin has at least one, preferably two or three, and more preferably all of the following characteristics:

[0109] - Tg greater than 25°C (especially between 30°C and 100°C), more preferably greater than 30°C (especially between 30°C and 95°C);

[0110] - Softening point greater than 50°C (especially between 50°C and 150°C);

[0111] - Number-average molar mass (Mn) between 300 g / mol and 2000 g / mol, preferably between 400 g / mol and 1500 g / mol;

[0112] - A polydispersity index (PDI) less than 3, preferably less than 2 (as a reminder: PDI = Mw / Mn, where Mw is the weight-average molar mass).

[0113] The above-mentioned preferred high-Tg plasticizing resins are known to those skilled in the art and are commercially available, for example, in the following ways:

[0114] - Polylimonene resin: sold by DRT under the name Dercolyte L120 (Mn = 625 g / mol; Mw = 1010 g / mol; PDI = 1.6; Tg = 72℃), or by Arizona under the name Sylvagum TR7125C (Mn = 630 g / mol; Mw = 950 g / mol; PDI = 1.5; Tg = 70℃);

[0115] -C5 fraction / vinyl aromatic copolymer resins (especially C5 fraction / styrene or C5 fraction / C9 fraction copolymer resins): sold by Neville Chemical Company under the names Super Nevtac 78, Super Nevtac 85 and Super Nevtac 99, by Goodyear Chemicals under the name Wingtack Extra, by Kolon under the names Hikorez T1095 and Hikorez T1100, or by Exxon under the names Escorez 2101 and Escorez 1273;

[0116] - Limonene / styrene copolymer resin: sold by DRT under the name Dercolyte TS105 or by Arizona Chemical Company under the names ZT115LT and ZT5100.

[0117] According to the present invention, the plasticizing resin with a glass transition temperature higher than 20°C may be selected from: cyclopentadiene (abbreviated as CPD) homopolymer or copolymer resin, dicyclopentadiene (abbreviated as DCPD) homopolymer or copolymer resin, terpene homopolymer or copolymer resin, C5 fraction homopolymer or copolymer resin, C9 fraction homopolymer or copolymer resin, α-methylstyrene homopolymer or copolymer resin, and mixtures thereof. Preferably, the plasticizing resin is selected from: (D)CPD / vinyl aromatic copolymer resin, (D)CPD / terpene copolymer resin, terpene / phenol copolymer resin, (D)CPD / C5 fraction copolymer resin, (D)CPD / C9 fraction copolymer resin, terpene / vinyl aromatic copolymer resin, terpene / phenol copolymer resin, C5 fraction / vinyl aromatic copolymer resin, and mixtures thereof.

[0118] The term "terpene" here refers to α-pinene, β-pinene, and limonene monomers in a known manner; preferably, limonene monomers are used, which are known to exist in three possible isomers: L-limonene (levorotatory enantiomer), D-limonene (dextrorotatory enantiomer), or dipentene (a racemic mixture of the dextrorotatory and levorotatory enantiomers). Suitable vinyl aromatic monomers include, for example, styrene, α-methylstyrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, vinyltoluene, p-(tert-butyl)styrene, methoxystyrene, chlorostyrene, hydroxystyrene, vinyltrimethylbenzene, divinylbenzene, vinylnaphthalene, or those derived from C9 fractions (or more generally from C8 to C9). 10 Any vinyl aromatic monomer (fraction).

[0119] More specifically, reference may be made to plasticizing resins selected from (D)CPD homopolymer resins, (D)CPD / styrene copolymer resins, polylimonene resins, limonene / styrene copolymer resins, limonene / D(CPD) copolymer resins, C5 fraction / styrene copolymer resins, C5 fraction / C9 fraction copolymer resins, and mixtures thereof.

[0120] All of the aforementioned plasticizing resins are known to those skilled in the art and are commercially available, such as polylimonene resin sold by DRT under the name Dercolyte, C5 fraction / styrene or C5 fraction / C9 fraction resin sold by Neville Chemical Company under the name Super Nevtac, by Kolon under the name Hikorez, or by Exxon Mobil under the name Escorez, or a mixture of aromatic and / or aliphatic resins sold by Struktol under the names 40MS or 40NS.

[0121] Advantageously, the content of the plasticizing resin with a glass transition temperature above 20°C in the composition according to the invention is in the range of 1 phr to 99 phr, preferably 5 phr to 95 phr, preferably 10 phr to 90 phr, and preferably 15 phr to 85 phr. Those skilled in the art will readily understand that when the content of the plasticizing resin with a glass transition temperature above 20°C is below the minimum content of the plasticizing system (the plasticizing system comprises at least one plasticizer that is liquid at 23°C and / or at least one plasticizing resin with a glass transition temperature above 20°C), the composition comprises at least the balance of a plasticizer that is liquid at 23°C. When the composition according to the invention does not contain a plasticizer that is liquid at 23°C, the content of the resin with a glass transition temperature above 20°C in the composition is advantageously in the range of 10 phr to 90 phr, preferably 15 phr to 85 phr, and preferably 20 phr to 80 phr.

[0122] II-2.2 is a liquid plasticizer at 23°C.

[0123] Any plasticizer (or oil) that is liquid at 23°C and has plasticizing properties for diene elastomers can be used, whether it is aromatic or non-aromatic. At ambient temperature (23°C), these plasticizers or these oils (which are more or less viscous) are liquid (as a reminder, i.e., substances that can eventually take on their container shape), which is particularly in contrast to plasticized resins that are essentially solid at ambient temperature.

[0124] Particularly suitable plasticizers that are liquid at 23°C are selected from: liquid diene polymers, polyolefin oils, naphthenic oils, paraffin oils, DAE oils, MES (medium extraction solvate) oils, TDAE (treated distilled aromatic extract) oils, RAE (residual aromatic extract) oils, TRAE (treated residual aromatic extract) oils, SRAE (safe residual aromatic extract) oils, mineral oils, vegetable oils, ether plasticizers, ester plasticizers, phosphate ester plasticizers, sulfonate ester plasticizers, and mixtures of these plasticizers that are liquid at 23°C.

[0125] For example, a plasticizer that is liquid at 23°C can be petroleum-based, preferably non-aromatic. A liquid plasticizer is described as a non-aromatic liquid plasticizer when the content of polycyclic aromatic compounds relative to the total weight of the plasticizer, as determined by the extract in DMSO according to method IP 346, is less than 3% by weight.

[0126] Plasticizers that are liquid at 23°C can also be liquid polymers derived from the polymerization of olefins or dienes, such as polybutene, polydiene (especially polybutadiene, polyisoprene (also known as LIR), or copolymers of butadiene and isoprene), butadiene, or copolymers of isoprene and styrene, or mixtures of these liquid polymers. The number-average molar mass of such liquid polymer is preferably in the range of 500 g / mol to 50,000 g / mol, more preferably 1,000 g / mol to 10,000 g / mol. As an example, Ricon products from Sartamomer can be mentioned.

[0127] When the plasticizer, which is liquid at 23°C, is a vegetable oil, it can be, for example, selected from the following oils: linseed oil, safflower oil, soybean oil, corn oil, cottonseed oil, rapeseed oil, castor oil, tung oil, pine oil, sunflower oil, palm oil, olive oil, coconut oil, peanut oil, grapeseed oil, and mixtures of these oils. The vegetable oil is preferably rich in oleic acid, meaning that the fatty acids derived from the vegetable oil (or, if multiple fatty acids are present, conjugated fatty acids) contain at least 60% by weight, and more preferably at least 70% by weight, of oleic acid. Sunflower oil is advantageously used as a vegetable oil, and the conjugated fatty acids derived from sunflower oil contain at least 60% by weight, preferably 70%, and, according to a particularly advantageous embodiment of the invention, at least 80% by weight of oleic acid.

[0128] According to another specific embodiment of the invention, the liquid plasticizer is a triester selected from carboxylic acid triesters, phosphate triesters, sulfonate triesters, and mixtures of these triesters.

[0129] Examples of phosphate ester plasticizers include phosphate ester plasticizers containing between 12 and 30 carbon atoms, such as trioctyl phosphate. Examples of carboxylic acid ester plasticizers include compounds selected from trimellitate, pyromellitic ester, phthalate, 1,2-cyclohexanedicarboxylate, adipate, azelaic acid ester, sebacic acid ester, triglycerides, and mixtures thereof. Among the aforementioned triesters, those preferably primarily (greater than 50% by weight, more preferably greater than 80% by weight) composed of unsaturated C atoms are particularly noteworthy. 18 Triglycerides composed of fatty acids (i.e., fatty acids selected from oleic acid, linoleic acid, linolenic acid, and mixtures of these acids). Triglycerides are preferred. More preferably, whether from synthetic or natural sources (e.g., in the case of sunflower oil or rapeseed oil), the fatty acids used consist of more than 50% by weight, and even more preferably more than 80% by weight, of oleic acid. Such triglycerides (trioleic acid esters) with a high oleic acid content are known; they are described, for example, as plasticizers for tire treads in patent application WO 02 / 088238.

[0130] When the plasticizer that is liquid at 23°C is an ether plasticizer, it can be, for example, polyethylene glycol or polypropylene glycol.

[0131] Preferably, the plasticizer that is liquid at 23°C is selected from: MES oil, TDAE oil, naphthenic oil, vegetable oil, and mixtures of these plasticizers that are liquid at 23°C. More preferably, the plasticizer that is liquid at 23°C is a vegetable oil, preferably sunflower oil.

[0132] Furthermore, the compositions according to the invention do not contain any liquid polymers.

[0133] Advantageously, the content of the plasticizer that is liquid at 23°C in the composition according to the invention is in the range of 1 phr to 49 phr, preferably 5 phr to 40 phr. Those skilled in the art will readily understand that when the content of the plasticizer that is liquid at 23°C is below the minimum content of the plasticizing system (the plasticizing system comprises at least one plasticizer that is liquid at 23°C and / or at least one plasticizing resin with a glass transition temperature higher than 20°C), the composition comprises at least the balance of a plasticizing resin with a glass transition temperature higher than 20°C. When the composition according to the invention does not contain a resin with a glass transition temperature higher than 20°C, the content of the plasticizer that is liquid at 23°C in the composition is advantageously in the range of 20 phr to 49 phr, preferably 30 phr to 49 phr.

[0134] II-3 Reinforced Filler

[0135] The compositions according to the invention may also contain reinforcing fillers. Such reinforcing fillers are typically composed of nanoparticles with an average (by weight) size of less than one micrometer, typically less than 500 nm, most typically between 20 nm and 200 nm, and particularly and more preferably between 20 nm and 150 nm.

[0136] The reinforcing filler may comprise carbon black, silica, or mixtures thereof. The composition according to the invention may consist primarily of silica. Alternatively, it may consist primarily (preferably only) of carbon black.

[0137] Those skilled in the art can adjust the content of reinforcing filler according to the intended use of the rubber composition. Advantageously, the content of reinforcing filler in the compositions according to the invention is in the range of 30 phr to 200 phr, preferably 40 phr to 190 phr, and more preferably 50 phr to 180 phr.

[0138] All carbon blacks (particularly those conventionally used in tires or their treads) are suitable as carbon blacks. Among these, the reinforcing carbon blacks of the 100, 200, and 300 series, or the carbon blacks of the 500, 600, or 700 series (ASTM D-1765-2017 grade), such as N115, N134, N234, N326, N330, N339, N347, N375, N550, N683, and N772, will be mentioned more specifically. These carbon blacks can be used commercially available in their standalone state, or in any other form (e.g., as a carrier for some rubber additives used). Carbon blacks can, for example, be incorporated into diene elastomers (particularly isoprene elastomers) in masterbatch form (see, for example, patent applications WO97 / 36724-A2 or WO99 / 16600-A1).

[0139] Suitable silica includes any type of precipitated silica, particularly highly dispersible precipitated silica (referred to as "HDS," used to denote "highly dispersible" or "highly dispersible silica"). These precipitated silicas (which may or may not be highly dispersible precipitated silica) are well known to those skilled in the art. Reference may be made to silica described, for example, in patent applications WO03 / 016215-A1 and WO03 / 016387-A1. In commercial HDS silica, silica from Evonik may be used in particular. 5000GR and 7000GR silica, or from Solvay 1085GR 1115MP 1165MP Premium 200MP and HRS1200MP silica. As a non-HDS silica, the following commercial silica can be used: from Evonik... VN2GR and VN3GR silica, from Solvay 175GR silica, or Hi-Sil EZ120G(-D), Hi-Sil EZ160G(-D), Hi-Sil EZ200G(-D), Hi-Sil 243LD, Hi-Sil 210 and Hi-Sil HDP 320G silica from PPG.

[0140] To couple silica to a diene elastomer, a coupling agent (or binder) that is at least bifunctional can be used in a known manner to provide a connection between the inorganic filler (its particulate surface) and the diene elastomer with satisfactory chemical and / or physical properties. Organosilanes or polyorganosiloxanes that are at least bifunctional are particularly used. The term "bifunctional" is understood to mean a compound having a first functional group capable of interacting with the inorganic filler and a second functional group capable of interacting with the diene elastomer. For example, such a bifunctional compound may contain a first functional group containing silicon atoms and a second functional group containing sulfur atoms, the first functional group being capable of interacting with the hydroxyl groups of the inorganic filler and the second functional group being capable of interacting with the diene elastomer.

[0141] Preferably, the organosilane is selected from (symmetric or asymmetric) organosilane polysulfides (e.g., bis(3-triethoxysilylpropyl)tetrasulfide (abbreviated TESPT) sold by Evonik under the name Si69, or bis(3-triethoxysilylpropyl)disulfide (abbreviated TESPD) sold by Evonik under the name Si75), polyorganosiloxanes, mercaptosilanes, and terminal mercaptosilanes (e.g., S-(3-(triethoxysilyl)propyl)octanethioate sold by Momentive under the name NXT Silane). More preferably, the organosilane is an organosilane polysulfide.

[0142] When using silica, those skilled in the art can readily adjust the content of the coupling agent in the compositions of the present invention. Typically, the content of the coupling agent is from 0.5% to 15% by weight relative to the amount of silica.

[0143] II-4 crosslinking system

[0144] The crosslinking system can be any type of system known to those skilled in the art of tire rubber compositions. The crosslinking system may be particularly based on sulfur and / or peroxides and / or bismaleimides.

[0145] Preferably, the crosslinking system is based on sulfur; it is then referred to as a vulcanization system. Sulfur can be provided in any form (particularly molecular sulfur or sulfur donor). It is also preferred that at least one vulcanization accelerator is present, and optionally, and even more preferably, various known vulcanization activators or known vulcanization retarders can be used, such as zinc oxide, stearic acid or equivalent compounds (e.g., stearates) and transition metal salts, guanidine derivatives (particularly diphenylguanidine).

[0146] The sulfur content is preferably between 0.3 phr and 10 phr, more preferably between 0.3 phr and 5 phr. The main vulcanization accelerator is preferably between 0.5 phr and 10 phr, more preferably between 0.5 phr and 5 phr.

[0147] As accelerators, any compound capable of acting as a vulcanization accelerator for diene elastomers in the presence of sulfur can be used, particularly thiazole-type accelerators and their derivatives, or accelerators of the sulfenamide, thiuram, dithiocarbamate, dithiophosphate, thiourea, and xanthate types. Examples of such accelerators include, in particular, the following compounds: 2-mercaptobenzothiazole disulfide (abbreviated “MBTS”), N-cyclohexyl-2-benzothiazole sulfenamide (“CBS”), N,N-dicyclohexyl-2-benzothiazole sulfenamide (“DCBS”), N-(tert-butyl)-2-benzothiazole sulfenamide (“TBBS”), N-(tert-butyl)-2-benzothiazole sulfenimide (“TBSI”), tetrabenzylthiuram disulfide (“TBZTD”), zinc dibenzyl dithiuramate (“ZBEC”), and mixtures of these compounds.

[0148] II.5 Possible Additives

[0149] The compositions used for the purposes of this invention may also contain all or part of common additives typically used in elastomer compositions intended for use in tires, such as processing aids, pigments, and protective agents (e.g., anti-ozone waxes, chemical anti-ozone agents, antioxidants).

[0150] II-6 laminate

[0151] According to the present invention, the laminate comprises at least two (preferably strictly two) adjacent layers, referred to as the "first layer" and the "second layer".

[0152] -The first layer is composed of the composition according to the invention.

[0153] - The rubber composition constituting the second layer is based on a diene elastomer and a crosslinking system, wherein the diene elastomer has a diene unit content of more than 50% by weight.

[0154] The term "adjacent layers" is intended to mean that the layers are at least partially in contact with each other.

[0155] The thickness of the first layer of the laminate according to the invention can be in the range of 0.2 mm to 120 mm, preferably 0.3 mm to 15 mm.

[0156] Advantageously, the thickness of the first layer of the laminate according to the invention is in the range of 0.5 mm to 120 mm, preferably 1 mm to 15 mm. These dimensions are particularly advantageous when the first layer constitutes the outer layer of a tire (e.g., tire sidewall or tire tread).

[0157] The thickness of the first layer of the laminate according to the invention can also be in the range of 0.2 mm to 10 mm, preferably 0.3 mm to 5 mm. These dimensions are particularly advantageous when the first layer forms the adhesive layer between two tire layers.

[0158] Regardless of the thickness of the first layer, the thickness of the second layer is preferably in the range of 0.2 mm to 10 mm, more preferably 0.3 mm to 7 mm.

[0159] The first and second layers of a laminate can overlap completely or partially.

[0160] The diene elastomers in the second layer composition, with a diene unit weight content greater than 50%, are selected from polybutadiene (BR), natural rubber (NR), synthetic polyisoprene (IR), butadiene copolymers, isoprene copolymers, and mixtures of these elastomers.

[0161] Preferably, the diene elastomer in the composition of the second layer, wherein the weight content of the diene unit is greater than 50%, is selected from isoprene elastomers.

[0162] Advantageously, the isoprene elastomer has a cis-1,4 bond weight content of at least 90% of the polyisoprene, preferably at least 98% of the polyisoprene.

[0163] Preferably, the polyisoprene is selected from natural rubber, synthetic polyisoprene, and mixtures thereof. More preferably, the polyisoprene is natural rubber.

[0164] Particularly advantageously, both the diene elastomers with a first layer diene unit content greater than 50% by weight and the diene elastomers with a second layer diene unit content greater than 50% by weight are polyisoprene, and may be the same or different. Preferably, both the diene elastomers with a first layer diene unit content greater than 50% by weight and the diene elastomers with a second layer diene unit content greater than 50% by weight have a cis-1,4 bond content of at least 90% by weight of the polyisoprene, more preferably at least 98% polyisoprene.

[0165] Advantageously, the elastomeric matrix of the composition of the second layer of the laminate according to the invention primarily comprises a diene elastomer with a diene unit weight content greater than 50%. The content of the diene elastomer with a diene unit weight content greater than 50% in the composition of the second layer of the laminate according to the invention is advantageously in the range of 60 phr to 100 phr, preferably 80 phr to 100 phr, more preferably 90 phr to 100 phr. Particularly advantageously, the content of the diene elastomer with a diene unit weight content greater than 50% in the composition of the second layer of the laminate according to the invention is 100 phr.

[0166] The composition of the second layer of the laminate according to the invention may further comprise reinforcing fillers. The reinforcing fillers of the second layer may comprise carbon black, silica, or mixtures thereof. Advantageously, the composition of the second layer of the laminate according to the invention is primarily composed of (preferably only of) carbon black. Alternatively, the composition of the second layer of the laminate according to the invention may be primarily composed of silica.

[0167] Those skilled in the art can adjust the content of reinforcing filler according to the intended use of the rubber composition. Advantageously, the content of reinforcing filler in the composition of the second layer of the laminate according to the invention is in the range of 20 phr to 80 phr, preferably 25 phr to 70 phr, and more preferably 30 phr to 60 phr.

[0168] The properties of the reinforcing filler can be as described above for the composition of the first layer of the laminate, and the reinforcing filler of the first layer and the reinforcing filler of the second layer are not necessarily the same.

[0169] When silica is used in the second layer of the laminate according to the invention, those skilled in the art can readily adjust the content of the coupling agent in the composition of the second layer of the laminate. Typically, the content of the coupling agent is from 0.5% by weight to 15% by weight relative to the amount of silica.

[0170] The crosslinking system of the composition of the second layer of the laminate according to the invention can be any type of system known to those skilled in the art of tire rubber compositions. The crosslinking system can be particularly based on sulfur and / or peroxides and / or bismaleimide.

[0171] Preferably, the crosslinking system of the composition of the second layer of the laminate according to the invention is based on sulfur; it is then referred to as a vulcanization system. Sulfur can be provided in any form (particularly molecular sulfur or sulfur donor). It is also preferred that at least one vulcanization accelerator is present, and optionally, and even more preferably, various known vulcanization activators or known vulcanization retarders can be used, such as zinc oxide, stearic acid or equivalent compounds (e.g., stearates) and transition metal salts, guanidine derivatives (particularly diphenylguanidine).

[0172] The sulfur content is preferably between 0.3 phr and 10 phr, more preferably between 0.3 phr and 5 phr. The main vulcanization accelerator is preferably between 0.5 phr and 10 phr, more preferably between 0.5 phr and 5 phr.

[0173] As an accelerator, any compound that acts as a vulcanization accelerator for diene elastomers in the presence of sulfur can be used, as described above for the composition of the first layer of the laminate, but these accelerators are not necessarily the same.

[0174] The composition of the second layer of the laminate for the purposes of this invention may also contain all or part of common additives typically used in elastomer compositions intended for use in tires, such as processing aids, plasticizers, pigments, and protective agents (e.g., anti-ozone waxes, chemical anti-ozone agents, antioxidants).

[0175] Preparation of II-7 Rubber Composition

[0176] The compositions that can be used in the laminates according to the invention can be manufactured in a suitable mixer using two consecutive preparation stages known to those skilled in the art:

[0177] - The first stage of thermomechanical processing or kneading (“non-production” stage), which can be carried out in a single thermomechanical stage, involves introducing all necessary components (particularly the elastomer matrix, reinforcing fillers, and various other optional additives besides the crosslinking system) into a suitable mixer (e.g., a standard closed mixer (e.g., a 'Banbury' type)). During thermomechanical kneading, optional fillers can be introduced into the elastomer in one or multiple batches. Where the filler has been fully or partially introduced into the elastomer in masterbatch form (e.g., as described in patent applications WO 97 / 36724 or WO 99 / 16600), the masterbatch is kneaded directly, where appropriate, introducing other elastomers or fillers present in the composition not in masterbatch form, and various other optional additives besides the crosslinking system. The non-production stage can be carried out at high temperatures, with a maximum temperature between 110°C and 200°C, preferably between 130°C and 185°C, for a duration typically between 2 and 10 minutes.

[0178] - After the mixture obtained in the first non-production stage is cooled to a lower temperature (typically less than 120°C, for example, between 40°C and 100°C), a second stage of machining (“production” stage) is carried out in an open mixer (e.g., a two-roll mill). The crosslinking system is then introduced, and the combined mixture is mixed for several minutes, for example, between 5 and 15 minutes.

[0179] These stages have been described, for example, in patent applications EP-A-0501227, EP-A-0735088, EP-A-0810258, WO 00 / 05300, or WO 00 / 05301.

[0180] The resulting final composition is then calendered, for example, in the form of sheets or plates (particularly for laboratory characterization), or extruded (or co-extruded with another rubber composition) as a rubber semi-finished product (or molding element). Regarding laminates, according to techniques known to those skilled in the art, the first and second layers can be produced separately, and then one layer can be laid on top of the other during tire manufacturing.

[0181] The composition can be in an uncured state (before crosslinking or vulcanization) or a cured state (after crosslinking or vulcanization). It can be a semi-finished product that can be used in tires.

[0182] Crosslinking (or curing) (or vulcanization where appropriate) is carried out in a known manner at a temperature typically between 130°C and 200°C for a sufficient time (e.g., varying between 5 minutes and 90 minutes), the time being particularly dependent on the curing temperature, the crosslinking system employed, and the crosslinking kinetics of the composition under consideration.

[0183] II-8 Rubber Products

[0184] Another subject of the invention is a rubber article comprising at least one composition according to the invention or comprising at least one laminate according to the invention. The rubber article may be selected from pneumatic tires, non-pneumatic tires, tracks, conveyor belts, and vibration damping articles. Preferably, the rubber article is selected from pneumatic tires, non-pneumatic tires, and conveyor belts. More preferably, the rubber article is a pneumatic or non-pneumatic tire.

[0185] More particularly, another subject of the invention is a pneumatic or non-pneumatic tire having a tread comprising a composition according to the invention or a first layer comprising a laminate according to the invention. Preferably, the composition according to the invention constitutes part or all of the tire tread, or the first layer of the laminate constitutes part or all of the tire tread, and the second layer of the laminate constitutes part or all of the tread base layer.

[0186] Another subject of the invention is a pneumatic tire, wherein the composition according to the invention constitutes part or all of at least one sidewall, or the first layer of the laminate constitutes part or all of at least one sidewall of the tire, and the second layer of the laminate constitutes part or all of the carcass ply.

[0187] The tires according to the invention can be designed to fit any type of vehicle, particularly motor vehicles, without any particular limitation.

[0188] III - Preferred Implementation Scheme

[0189] Based on the above description, preferred embodiments of the present invention are described as follows:

[0190] 1. A rubber composition, said rubber composition being based on:

[0191] A copolymer of at least one ethylene, a first 1,3-diene, and a second 1,3-diene of formula (I) from -20 phr to 100 phr, wherein the first 1,3-diene is 1,3-butadiene, isoprene, or a mixture thereof, and the ethylene units in the copolymer account for more than 50 mol% of the monomer units of the copolymer.

[0192] CH2=CR-CH=CH2(I)

[0193] The symbol R represents a hydrocarbon chain with 3 to 20 carbon atoms;

[0194] At least one diene elastomer from -0 phr to 80 phr, wherein the diene elastomer contains more than 50% by weight of diene units;

[0195] A plasticizing system ranging from -10 phr to 100 phr, wherein the plasticizing system comprises at least one plasticizing resin with a glass transition temperature above 20°C and / or at least one plasticizer that is liquid at 23°C.

[0196] -Reinforced fillers; and

[0197] - Crosslinking system.

[0198] 2. The composition according to embodiment 1, wherein the copolymer comprises ethylene units in an amount between 50 mol% and 95 mol% of the monomer units of the copolymer, preferably 60 mol% to 90 mol%, and more preferably 70 mol% to 85 mol%.

[0199] 3. The composition according to any of the foregoing embodiments, wherein the symbol R of the copolymer represents a hydrocarbon chain having 6 to 16 carbon atoms.

[0200] 4. The composition according to any of the foregoing embodiments, wherein the symbol R of the copolymer represents an aliphatic chain.

[0201] 5. The composition according to any of the foregoing embodiments, wherein the symbol R of the copolymer represents a non-cyclic chain.

[0202] 6. The composition according to any of the foregoing embodiments, wherein the symbol R of the copolymer represents a linear or branched chain.

[0203] 7. The composition according to any of the foregoing embodiments, wherein the first 1,3-diene of the copolymer is 1,3-butadiene.

[0204] 8. The composition according to any of the foregoing embodiments, wherein the copolymer comprises a first 1,3-diene unit in an amount between 1 mol% and 49 mol% of the monomer units of the copolymer, preferably between 4 mol% and 29 mol%, and more preferably between 4 mol% and 25 mol%.

[0205] 9. The composition according to any of the foregoing embodiments, wherein the 1,3-diene of formula (I) is myrcene, β-farnesene, or a mixture of myrcene and β-farnesene.

[0206] 10. The composition according to any of the foregoing embodiments, wherein the copolymer comprises 1,3-diene units of formula (I) in a concentration between 1 mol% and 50 mol% of the monomer units of the copolymer, preferably between 1 mol% and 30 mol%, and more preferably between 5 mol% and 30 mol%.

[0207] 11. The composition according to any of the foregoing embodiments, wherein the copolymer is a random copolymer.

[0208] 12. The composition according to any of the foregoing embodiments, wherein the glass transition temperature of the copolymer is below -35°C, preferably between -90°C and -35°C, and more preferably between -70°C and -35°C.

[0209] 13. The composition according to any of the foregoing embodiments, wherein the copolymer content is in the range of greater than 50 phr to 100 phr, preferably 75 phr to 100 phr, more preferably 90 phr to 100 phr.

[0210] 14. The composition according to embodiment 13, wherein the diene elastomer, comprising a diene unit weight content greater than 50%, is present in an amount ranging from 0 phr to less than 50 phr, preferably from 0 phr to 25 phr, and more preferably from 0 phr to 10 phr.

[0211] 15. The composition according to any one of embodiments 1 to 12, wherein the copolymer content is in the range of 20 phr to 90 phr, preferably 25 phr to 80 phr, more preferably 30 phr to 80 phr.

[0212] 16. The composition according to embodiment 15, wherein the diene elastomer, comprising a diene unit content greater than 50% by weight, is present in an amount ranging from 10 phr to 80 phr, preferably from 20 phr to 75 phr, more preferably from 20 phr to 70 phr.

[0213] 17. The composition according to any of the foregoing embodiments, wherein the composition does not contain any elastomer other than a diene elastomer having a copolymer and diene unit weight content greater than 50%.

[0214] 18. The composition according to any of the foregoing embodiments, wherein the diene elastomer, comprising more than 50% by weight of the diene unit, is selected from polybutadiene (BR), natural rubber (NR), synthetic polyisoprene (IR), butadiene copolymers, isoprene copolymers, and mixtures thereof.

[0215] 19. The composition according to any of the foregoing embodiments, wherein the diene elastomer having a diene unit weight content greater than 50% is polyisoprene, preferably having a cis-1,4 bond weight content of at least 90% of the weight of the polyisoprene, preferably at least 98%.

[0216] 20. The composition according to embodiment 19, wherein the polyisoprene is selected from natural rubber, synthetic polyisoprene, or mixtures thereof.

[0217] 21. The composition according to any of the foregoing embodiments, wherein the content of the plasticizing system comprising at least one plasticizer that is liquid at 23°C and / or at least one plasticizing resin with a glass transition temperature higher than 20°C is in the range of 35 phr to 100 phr, preferably 50 phr to 95 phr, more preferably 55 phr to 90 phr.

[0218] 22. The composition according to any of the foregoing embodiments, wherein the plasticizing system comprises a plasticizer that is liquid at 23°C and a plasticizing resin with a glass transition temperature higher than 20°C.

[0219] 23. The composition according to any one of the foregoing embodiments, wherein the plasticizer, which is liquid at 23°C, is selected from liquid diene polymers, polyolefin oils, naphthenic oils, paraffin oils, DAE oils, MES oils, TDAE oils, RAE oils, TRAE oils, SRAE oils, mineral oils, vegetable oils, ether plasticizers, ester plasticizers, phosphate ester plasticizers, sulfonate plasticizers, and mixtures thereof.

[0220] 24. The composition according to any of the foregoing embodiments, wherein the content of the plasticizer, which is liquid at 23°C, is in the range of 1 phr to 49 phr, preferably 5 phr to 40 phr.

[0221] 25. The composition according to any of the foregoing embodiments, wherein the plasticizing resin with a glass transition temperature higher than 20°C is selected from cyclopentadiene homopolymer or copolymer resins, dicyclopentadiene homopolymer or copolymer resins, terpene homopolymer or copolymer resins, C5 fraction homopolymer or copolymer resins, C9 fraction homopolymer or copolymer resins, α-methylstyrene homopolymer or copolymer resins, and mixtures thereof.

[0222] 26. The composition according to any of the foregoing embodiments, wherein the content of the plasticizing resin with a glass transition temperature above 20°C is in the range of 1 phr to 99 phr, preferably 5 phr to 95 phr.

[0223] 27. The composition according to any of the foregoing embodiments, wherein the reinforcing filler comprises carbon black, silica, or a mixture thereof.

[0224] 28. The composition according to any of the foregoing embodiments, wherein the content of the reinforcing filler is in the range of 30 phr to 200 phr, preferably 40 phr to 190 phr, and more preferably 50 phr to 180 phr.

[0225] 29. The composition according to any of the foregoing embodiments, wherein the crosslinking system is a vulcanization system comprising molecular sulfur and / or at least one sulfur donor.

[0226] 30. An elastomeric laminate comprising at least two adjacent layers:

[0227] - The first layer consists of the composition according to any one of embodiments 1 to 29.

[0228] - The rubber composition constituting the second layer is based on a diene elastomer and a crosslinking system, wherein the diene elastomer has a diene unit content of more than 50% by weight.

[0229] 31. The laminate according to embodiment 30, wherein the diene elastomer of the composition of the second layer having a diene unit weight content of more than 50% is selected from polybutadiene (BR), natural rubber (NR), synthetic polyisoprene (IR), butadiene copolymer, isoprene copolymer, and mixtures of these elastomers.

[0230] 32. The laminate according to any one of embodiments 30 and 31, wherein the diene elastomer of the composition of the second layer having a diene unit weight content of more than 50% is polyisoprene, preferably the polyisoprene having a cis-1,4 bond weight content of at least 90% of the weight of the polyisoprene, preferably at least 98%.

[0231] 33. The laminate according to embodiment 32, wherein the polyisoprene of the composition of the second layer is selected from natural rubber, synthetic polyisoprene, or mixtures thereof.

[0232] 34. The laminate according to any one of embodiments 30 to 33, wherein the diene elastomer of the first layer with a diene unit weight content greater than 50% and the diene elastomer of the second layer with a diene unit weight content greater than 50% are both polyisoprene.

[0233] 35. The laminate according to any one of embodiments 30 to 34, wherein the diene elastomer of the first layer having a diene unit weight content of more than 50% and the diene elastomer of the second layer having a diene unit weight content of more than 50% are both cis-1,4 bond weight content of at least 90% of the weight of polyisoprene, preferably at least 98% of the polyisoprene.

[0234] 36. The laminate according to any one of embodiments 30 to 35, wherein the diene elastomer, with a diene unit weight content greater than 50%, is present in the composition of the second layer in an amount ranging from 60 phr to 100 phr, preferably from 80 phr to 100 phr, more preferably from 90 phr to 100 phr.

[0235] 37. The laminate according to any one of embodiments 30 to 36, wherein the composition of the second layer comprises reinforcing filler.

[0236] 38. The laminate according to embodiment 37, wherein the reinforcing filler of the composition of the second layer is mainly composed of carbon black, preferably only composed of carbon black.

[0237] 39. The laminate according to embodiment 37, wherein the reinforcing filler of the composition of the second layer is mainly composed of silicon dioxide.

[0238] 40. The laminate according to any one of embodiments 37 to 39, wherein the content of reinforcing filler in the composition of the second layer is in the range of 20 phr to 80 phr, preferably 25 phr to 70 phr, and more preferably 30 phr to 60 phr.

[0239] 41. The laminate according to any one of embodiments 30 to 40, wherein the crosslinking system of the second layer is a vulcanization system comprising molecular sulfur and / or at least one sulfur donor.

[0240] 42. The laminate according to any one of embodiments 30 to 41, wherein the thickness of the first layer is in the range of 0.5 mm to 120 mm, preferably 1 mm to 15 mm or 0.2 mm to 120 mm, preferably 0.3 mm to 15 mm.

[0241] 43. The laminate according to any one of embodiments 30 to 41, wherein the thickness of the first layer is in the range of 0.2 mm to 10 mm, preferably 0.3 mm to 5 mm.

[0242] 44. The laminate according to any one of embodiments 30 to 43, wherein the thickness of the second layer is in the range of 0.2 mm to 10 mm, preferably 0.3 mm to 7 mm.

[0243] 45. A rubber article comprising the composition according to any one of embodiments 1 to 29, or comprising a laminate defined according to any one of embodiments 30 to 44.

[0244] 46. ​​The rubber product according to embodiment 45, wherein the product is selected from pneumatic tires, non-pneumatic tires, tracks, conveyor belts and vibration damping products, preferably selected from pneumatic tires, non-pneumatic tires and conveyor belts.

[0245] 47. A pneumatic or non-pneumatic tire, the pneumatic or non-pneumatic tire comprising a laminate defined according to any one of embodiments 30 to 44, wherein a first layer of the laminate constitutes part or all of the tire tread, and a second layer of the laminate constitutes part or all of the tread subbase.

[0246] 48. A pneumatic or non-pneumatic tire, the pneumatic or non-pneumatic tire comprising a laminate defined according to any one of embodiments 30 to 44, wherein a first layer of the laminate constitutes part or all of at least one sidewall of the tire, and a second layer of the laminate constitutes part or all of the carcass ply.

[0247] IV-Example

[0248] Measurements and tests used in IV-1

[0249] IV-1.1 Determination of the microstructure of elastomers:

[0250] a) Determination of the microstructure of ethylene-butadiene copolymer (elastomer E1):

[0251] pass 1 The microstructure of the ethylene-butadiene copolymer was determined by 1H NMR analysis. 1 When the resolution of H NMR spectroscopy cannot assign and quantify all species, by 13C10 NMR analysis was used as an adjunct. Measurements were performed using a Brüker 500MHz NMR spectrometer at 500.43MHz for proton observation and 125.83MHz for carbon observation. For elastomers that are insoluble in solvent but have swelling capacity, protons and carbon were observed in proton-decoupled mode using a 4mm z-class HR-MAS probe. Spectra were acquired at rotation speeds from 4000Hz to 5000Hz. For measurements of soluble elastomers, protons and carbon were observed in proton-decoupled mode using a liquid NMR probe. Insoluble samples were prepared in a rotor filled with the analyte and a deuterated solvent (typically deuterated chloroform (CDCl3)) that allows swelling. The solvent used must always be deuterated, and its chemical properties can be adjusted by those skilled in the art. The amount of material used was adjusted to obtain spectra with sufficient sensitivity and resolution. Soluble samples are dissolved in a deuterated solvent (typically deuterated chloroform (CDCl3)) (approximately 25 mg of elastomer per ml). The solvent or solvent blend used must always be deuterated, and its chemical properties can be adjusted by someone skilled in the art. In both cases (soluble or swollen samples): For proton NMR, a simple 30° pulse sequence is used. The spectral window is set to observe all resonance lines belonging to the analyte. The cumulative number is adjusted to obtain a signal-to-noise ratio sufficient for quantification of each unit. The cyclic delay between each pulse is adjusted to obtain a quantitative measurement. For carbon NMR, a simple 30° pulse sequence is used, and proton decoupling is performed only during acquisition to avoid the nuclear Auster effect (NOE) and maintain quantification. The spectral window is set to observe all resonance lines belonging to the analyte. The cumulative number is adjusted to obtain a signal-to-noise ratio sufficient for quantification of each unit. The cyclic delay between each pulse is adjusted to obtain a quantitative measurement. NMR measurements are performed at 25°C.

[0252] b) Determination of the microstructure of ethylene-myrcene copolymer (elastomer E2):

[0253] Spectral characterization and microstructure measurement of ethylene-myrcene copolymers were performed using nuclear magnetic resonance (NMR) spectroscopy.

[0254] Spectrometer: For these measurements, a Bruker Avance III HD 400MHz spectrometer equipped with a Bruker 5mm Class Z cryogenic BBFO probe was used.

[0255] Experiment: Recording radio frequency pulses with a tilt angle of 30° 1 Experiment H was repeated 128 times with a cycle delay of 5 seconds. HSQC (heteronuclear single-quantum coherence) and HMBC (heteronuclear multi-bond correlation) were recorded. 1 H- 13The C NMR experiments were repeated 128 times with an increment of 128. The experiments were conducted at 25°C.

[0256] Sample preparation: Dissolve 25 mg of sample in 1 ml of deuterated chloroform (CDCl3).

[0257] Sample calibration: at δ 1H =7.2ppm (for the most shielded signal) and δ 13C =77ppm (for the least shielded signal) protonated impurity calibration relative to solvent (CHCl3) 1 H and 13 The axis of C chemical shift.

[0258] Spectral identification of copolymers of ethylene and 1,3-myrcene: In the following expressions A, B, and C, symbols R1 and R2 denote the junctions of the unit and the polymer chain. The signals of the inserted forms of 1,3-diene A, B, and C were observed on different recorded spectra. According to S. George et al. (Polymer 55 (2014) 3869-3878), the characteristic signal of the -CH= group at the 8” position of form C... 1 H and 13 The C chemical shift is the same as that of the -CH= group at position 3. Table 1 shows the chemical shifts of characteristic signals for portions A, B, and C. Portions A, B, and C correspond to the 3,4 configuration, 1,2 configuration, and trans-1,4 configuration units, respectively. The chemical shifts of 1D were analyzed using Topspin software. 1 The integral of the H NMR spectrum is quantized. The integral signal used to quantize each part is:

[0259] Ethylene: Signal at 1.2 ppm corresponding to 4 protons

[0260] Total myrcene: signal corresponding to position 1 of 6 protons (1.59 ppm)

[0261] Form A: Signal at position 7 corresponding to 2 protons (4.67 ppm)

[0262] Form B: The signal corresponding to the 8' position of one proton (5.54 ppm).

[0263] Microstructure is quantified using the following mole percentage (mol%): mol% of a portion = mol% of a portion 1 H integral × 100 / Σ (for each part) 1 H-integral).

[0264] [Table 1]

[0265]

[0266]

[0267]

[0268] c) Determination of the microstructure of ethylene-butadiene-myrcene terpolymer (elastomer E3):

[0269] Spectroscopic characterization and measurement of the microstructure of ethylene-butadiene-myrcene copolymer were performed using nuclear magnetic resonance (NMR) spectroscopy.

[0270] These measurements were performed using a Bruker Avance IIIHD 400MHz spectrometer equipped with a Bruker 5mm Class Z cryogenic BBFO probe. Radio frequency pulses with a 30° tilt angle were used for recording. 1 Experiment H was repeated 128 times with a cycle delay of 5 seconds. HSQC (heteronuclear single-quantum coherence) and HMBC (heteronuclear multi-bond correlation) were recorded. 1 H- 13 The C NMR experiments were repeated 128 times with an increment of 128. The experiments were conducted at 25°C.

[0271] Dissolve 25 mg of the sample in 1 ml of deuterated o-dichlorobenzene (ODCB).

[0272] In δ 1H =7.2ppm (for the most shielded signal) and δ 13C =127ppm (for the least shielded signal) protonated impurity calibration relative to the solvent 1 H and 13 The axis of C chemical shift.

[0273] Possible monomer units in the terpolymer are -CH2-CH(CH=CH2)-, -CH2-CH=CH-CH2-, -CH2-CH2-, 1,2-cyclohexanediyl moiety, and the following structures, where R1 and R2 represent polymer chains:

[0274]

[0275] The 1,2-cyclohexane dimethyl moiety has the following structure:

[0276]

[0277] The signal of the inserted form of myrcene A was observed on different recorded spectra. According to S. Georges et al. (S. Georges, M. Bria, P. Zinck and M. Visseaux, Polymer, 55 (2014), 3869-3878), the characteristic signal of the -CH= group at the 8” position of form C...1 H and 13 The C chemical shift is the same as that of the -CH= group at position 3.

[0278] Table 2 shows the chemical shifts of the characteristic signals of the polymers (excluding the 1,3-butadiene units in the ethylene-butadiene-myrcene terpolymer). 1 H and 13 (Identification of C signal).

[0279] [Table 2]

[0280]

[0281] Using Topspin software for 1D 1 Quantization is performed by integrating the H NMR spectrum.

[0282] The integral signal used to quantize each part is:

[0283] Ethylene: All signals between 0.5 ppm and 3.0 ppm were calculated by subtracting the aliphatic contributions from the other parts of the terpolymer. The four protons corresponding to the ethylene moiety were calculated.

[0284] Form A: Signal at position 7 corresponding to 2 protons (4.86 ppm).

[0285] The proportion of form C cannot be obtained directly, but it can be calculated from the signal at position 3+8 by subtracting the contribution of form A.

[0286] PB1-4: Signals corresponding to two protons between 5.71 ppm and 5.32 ppm (by removing the contribution of PB1-2).

[0287] PB1-2: Signals corresponding to two protons between 5.11 ppm and 4.92 ppm.

[0288] Cyclohexane ring: signal corresponding to 2 protons between 1.80 ppm and 1.70 ppm.

[0289] The microstructure was quantified using the following mole percentages (mol%):

[0290] Partial mole % = Partial 1 H integral * 100 / Σ (for each part) 1 H-integral).

[0291] c) Determination of the microstructure of ethylene-butadiene-farnese terpolymers (elastomers E4 and E5):

[0292] Spectroscopic characterization and microstructure measurements of the ethylene-butadiene-farnesene copolymer were performed using nuclear magnetic resonance (NMR) spectroscopy. These measurements were performed using a Bruker Avance III HD 400MHz spectrometer equipped with a Bruker 5mm Z-level cryogenic BBFO probe. Radio frequency pulses with a 30° tilt angle were used for recording. 1 Experiment H was repeated 128 times with a cycle delay of 5 seconds. HSQC (heteronuclear single-quantum coherence) and HMBC (heteronuclear multi-bond correlation) were recorded. 1 H- 13 The 128-C NMR experiments were repeated 128 times with an increment of 128. The experiments were conducted at 25°C. 25 mg of sample was dissolved in 1 ml of deuterated o-dichlorobenzene (ODCB). δ¹⁺ NMR was used for the determination of the precipitate. 1H =7.2ppm (for the most shielded signal) and δ 13C =127ppm (for the least shielded signal) protonated impurity calibration relative to the solvent 1 H and 13 The axis of C chemical shift.

[0293] Possible monomer units in the terpolymer are -CH2-CH(CH=CH2)-, -CH2-CH=CH-CH2-, -CH2-CH2-, 1,2-cyclohexanediyl moiety, and the following structures, where R1 and R2 represent polymer chains:

[0294]

[0295] The signal of the inserted form of farnesene A was observed in different recorded spectra. The characteristic signal of the -CH= group at position 11” in form C was also observed. 1 H and 13 The C chemical shift is the same as that of the -CH= groups at positions 3 and 7.

[0296] Table 3 shows the chemical shifts of the characteristic signals of the polymers (excluding the 1,3-butadiene units in the ethylene-butadiene-farnese terpolymer). 1 H and 13 (Identification of C signal).

[0297] [Table 3]

[0298]

[0299] Using Topspin software for 1D 1 Quantization is performed by integrating the H NMR spectrum.

[0300] The integral signal used to quantize each part is:

[0301] Farnesene moiety A: The signal from the CH2= at position 14 of two protons.

[0302] Farnesene partial form C: signals from the CH= signals at positions 3, 11” and 7 of the two protons (by subtracting the contribution from form A),

[0303] Farnesene form B: Signal from position 11' of a single proton specific to this form.

[0304] PB1-4: Signals corresponding to two protons between 5.71 ppm and 5.32 ppm (by removing the contribution of PB1-2).

[0305] PB1-2: Signals corresponding to two protons between 5.11 ppm and 4.92 ppm.

[0306] Cyclohexane ring: signal corresponding to 2 protons between 1.80 ppm and 1.70 ppm.

[0307] The ethylene moiety is obtained by integrating all aliphatic signals (~0.5ppm to 3ppm) and subtracting the contributions of all other aliphatic moieties (PB1-4, PB1-2, EBR ring, farnesene forms A and C).

[0308] The microstructure was quantified using the following mole percentages (mol%):

[0309] Partial mole % = Partial 1 H integral * 100 / Σ (for each part) 1 H-integral).

[0310] IV-1.2 Determination of the glass transition temperature of polymers:

[0311] The glass transition temperature is measured by differential calorimetry (differential scanning calorimetry) according to standard ASTM D3418 (1999).

[0312] IV-1.3 Determination of the macroscopic structure of polymers by size exclusion chromatography (SEC):

[0313] a) Measurement principle:

[0314] Size exclusion chromatography, or SEC, separates macromolecules in solution based on their size by passing them through a column filled with a porous gel. Macromolecules are separated based on their hydrodynamic volume, with the largest macromolecules eluting first.

[0315] Combined with a triple detector (3D) (refractive meter, viscometer, and 90° light scattering detector), SEC provides a picture of the absolute molar mass distribution of the polymer. Individual number-average absolute molar mass (Mn) and weight-average absolute molar mass (Mw), as well as dispersibility, can also be calculated.

[0316] b) Polymer preparation:

[0317] Each sample was dissolved in tetrahydrofuran at a concentration of approximately 1 g / L. The solution was then filtered through a filter with a porosity of 0.45 μm prior to injection.

[0318] c) 3D SEC Analysis:

[0319] To determine the number-average molar mass (Mn), weight-average molar mass (Mw), and polydispersity index (PI) of a polymer (where appropriate), the following methods are used.

[0320] The number-average molar mass (Mn), weight-average molar mass (Mw), and polydispersity index of a polymer (hereinafter referred to as the sample) are determined in an absolute manner by triple detection size exclusion chromatography (SEC). The advantage of triple detection size exclusion chromatography is that it directly measures the average molar mass without calibration.

[0321] The refractive index increment dn / dc of a sample solution is measured online using the peak area detected by a refractometer (RI) in a liquid chromatography apparatus. For this method to be applied, it must be verified that 100% sample mass is injected and eluted through the column. The area of ​​the RI peak depends on the sample concentration, the RI detector constant, and the dn / dc value.

[0322] To determine the average molar mass, a pre-prepared and filtered 1 g / L solution was injected into the chromatographic system. A Waters Alliance line was used. The eluent was tetrahydrofuran containing 250 ppm BHT (2,6-di(tert-butyl)-4-hydroxytoluene), and the flow rate was 1 mL / min. -1 The system temperature was 35℃, and the analysis time was 60 min. A set of three Agilent columns, commercially available as PL Gel Mixed B LS, was used. The injected sample solution volume was 100 μl. The detection system consisted of a Wyatt differential viscometer (commercially known as Viscostar II), a Wyatt differential refractometer (commercially known as Optilab T-Rex with a wavelength of 658 nm), and a Wyatt multi-angle static light scattering detector (commercially known as Dawn Heleos 8+ with a wavelength of 658 nm).

[0323] To calculate the number-average molar mass and polydispersity index, the refractive index increment dn / dc of the sample solution obtained above was integrated. The software used to process the chromatographic data was the Astra system from Wyatt.

[0324] Synthesis of IV-2 polymer:

[0325] In polymer synthesis, all reactants except metallocenes are commercially available. Butyloctylmagnesium (BOMAG) (20% heptane, C = 0.88 mol / L) -1 The reagents were obtained from Chemtura and stored in Schlenk tubes under an inert atmosphere. Ethylene (N35 grade) was obtained from Air Liquide and was ready for use without prior purification. Myrcene (purity ≥95%) and farnesene (purity ≥95%) were obtained from Sigma-Aldrich.

[0326] The following polymers are synthesized according to the steps described below:

[0327] - A copolymer of ethylene and 1,3-butadiene: Elastomer E1 (not according to the invention)

[0328] - A copolymer of ethylene and myrcene: Elastomer E2 (not according to the invention)

[0329] - A copolymer of ethylene, butadiene, and farnesene: Elastomer E3 (according to the present invention)

[0330] - Copolymers of ethylene, butadiene, and myrcene: elastomers E4 and E5 (according to the present invention)

[0331] Butyloctylmagnesium (BOMAG) was added to a reactor containing methylcyclohexane, ethylene (Et), butadiene (Bd), and / or myrcene (Myr) and / or farnesene (Far) in the proportions shown in Table 4 at 80°C to neutralize impurities in the reactor, followed by the addition of a catalyst system (see Table 4). The reaction temperature was then adjusted to 80°C, and polymerization began. Polymerization was carried out at a constant pressure of 8 bar. During polymerization, ethylene, butadiene (Bd), and / or myrcene (Myr) and / or farnesene (Far) were fed into the reactor in the proportions specified in Table 4. Polymerization was terminated by cooling, reactor degassing, and the addition of ethanol. An antioxidant was added to the polymer solution. The copolymer was recovered by drying to constant weight in a vacuum oven. The catalyst system was a pre-formed catalyst system. It was prepared in methylcyclohexane by metallocene [Me₂SiFlu₂Nd(μ-BH₄)₂Li(THF)], co-catalyst butyloctylmagnesium (BOMAG), and preform monomer 1,3-butadiene in the contents shown in Table 4. It was prepared according to the preparation method in Section II.1 of patent application WO2017 / 093654 A1.

[0332] Tables 5 and 6 show the microstructure and properties of elastomers E1 to E5. For the microstructure, Table 5 shows the molar contents of ethylene (Eth) units, 1,3-butadiene units, 1,2-cyclohexanediyl (cyclic) moieties, and β-farnesene or myrcene units. The molar proportions of β-farnesene or myrcene units are also shown according to whether they are 1,4, 1,2, or 3,4 configurations.

[0333] [Table 4]

[0334]

[0335] [Table 5]

[0336]

[0337]

[0338] [Table 6]

[0339] elastomer E1 E2 E3 E4 E5 Tg (°C) -40 -60 -61 -49 -49 Mn(g / mol) 128888 367400 200800 298000 179500

[0340] Preparation of IV-3 rubber composition:

[0341] In the following examples, the rubber composition was prepared as described in point II-7 above. Specifically, the "non-production" stage was carried out for 5 minutes in a 3-liter mixer with an average blade speed of 50 rpm until the maximum discharge temperature of 160°C was reached. The "production" stage was carried out for 10 minutes in an open mill at 23°C.

[0342] IV-4 rubber test:

[0343] Based on the properties of the copolymers and the content of plasticizers in the compositions, the adhesive properties of several rubber compositions containing copolymers comprising ethylene units and 1,3-diene units were compared with those of compositions based on natural rubber.

[0344] The natural rubber-based layers tested for adhesion to compositions T1 to T7 (not according to the invention) and compositions C1 to C3 (according to the invention) correspond to compositions conventionally used as inner tire layers (e.g., carcass ply or tread base layer). Table 7 below shows the compositions (T0) of this natural rubber-based layer.

[0345] Compare the adhesive properties of compositions T1 to T7 and C1 to C3 with composition T0. Control compositions T1 and T6 are not according to the invention because elastomer E1, containing more than 50 mol% ethylene units, does not contain the 1,3-diene unit of formula (I). Control composition T7 is not according to the invention because elastomer E2 does not contain 1,3-diene, which is 1,3-butadiene, isoprene, or a mixture thereof. Control compositions T1 to T5 are not according to the invention because they do not contain the plasticizing system according to the invention. Compositions T6, T7, C1, C2, and C3 differ from compositions T1, T2, T3, T4, and T5, respectively, only in the presence of the plasticizing system according to the invention. It should be noted that the silica content is adjusted to keep the filler volume fraction constant. The filler volume fraction in the rubber composition is defined as the ratio of the filler volume to the volume of all components of the composition. It should be understood that the volume of all components is calculated by adding the volumes of each component of the composition.

[0346] Adhesion testing was performed using a T-peel test (also known as a 180° peel test). A peel specimen was prepared by bringing the two layers to be tested (compositions constituting the layers in an uncured state) into contact. A crack initiator was inserted between these two layers. Each layer was reinforced by a composite cord layer that restricted deformation of the layer under tension. After assembly, the specimen was heated to 150°C at 16 bar for 30 minutes. A strip with a width of 30 mm was then cut using a cutter. The two sides of the crack initiator were then placed into the jaws of an Instron tensile testing machine. The test was performed at 20°C and a pulling speed of 100 mm / min. The tensile stress was recorded and normalized to the width of the specimen. A curve was obtained showing the strength per unit width (in N / mm) as a function of the movable crosshead displacement of the tensile testing machine (between 0 mm and 200 mm). The selected adhesion value corresponds to the crack propagation within the specimen and therefore to the average stable value of the curve. The adhesiveness values ​​of the examples were also standardized (base 100) relative to control T1 for compositions T2 to T5 or to control T6 for compositions C1 to C3. An index greater than 100 indicates a greater improvement in adhesiveness.

[0347] Table 7 shows the compositions tested (in phr) and the results obtained.

[0348] [Table 7]

[0349]

[0350]

[0351] (1) Prepare elastomers E1 to E5 according to the method described in point IV-2 above.

[0352] (2) Carbon black N330 according to standard ASTM D-1765-2017

[0353] (3) Silica, Zeosil 1165MP sold by Solvay.

[0354] (4) Triethoxysilylpropyltetrasulfide (TESPT) liquid silane, from Evonik's Si69

[0355] (5) Gum rosin (GEM SPE1) from Diamantino Malho

[0356] (6) Escorez 1102 tackifying resin from EXXON (Mn = 1370 g / mol; PDI = 2.3)

[0357] (7) Escorez 5000 series petroleum hydrocarbon resins from Exxon Mobil (Tg = 52℃)

[0358] (8) MES oil, Catenex SNR sold by Shell

[0359] (9) Diphenylguanidine, from Flexsys' Perkacit DPG

[0360] (10) Anti-ozone wax, Varazon 4959 from Sasol Wax

[0361] (11) N-(1,3-dimethylbutyl)-N-phenyl-p-phenylenediamine, from Flexsys' Santoflex 6-PPD

[0362] (12) Industrial-grade zinc oxide from Umicore

[0363] (13) N-cyclohexyl-2-benzothiazole sulfenamide, from Santocure CBS of Flexsys

[0364] These results indicate that rubber compositions comprising copolymers of ethylene, a first 1,3-diene (which is different from that of formula (I)) and a second 1,3-diene of formula (I) combined with a plasticizing system according to the invention can improve adhesion to diene compositions compared to rubber compositions comprising copolymers of ethylene, a first 1,3-diene (which is 1,3-butadiene, isoprene or a mixture thereof) and a second 1,3-diene of formula (I).

Claims

1. A rubber composition, said rubber composition being based on: - A copolymer of at least one ethylene, a first 1,3-diene, and a second 1,3-diene of formula (I) from 20 phr to 100 phr, wherein the first 1,3-diene is 1,3-butadiene, isoprene, or a mixture thereof, and the ethylene units in the copolymer account for more than 50 mol% of the monomer units of the copolymer. CH2=CR-CH=CH2(I) The symbol R represents a hydrocarbon chain with 3 to 20 carbon atoms; - At least one diene elastomer of 0 phr to 80 phr, wherein the diene elastomer contains more than 50% by weight of diene units; - A plasticizing system of 10 phr to 100 phr, wherein the plasticizing system comprises at least one plasticizing resin with a glass transition temperature above 20°C and / or at least one plasticizer that is liquid at 23°C; - Reinforcing fillers; and - Crosslinking system.

2. The composition according to claim 1, wherein, The copolymer contains ethylene units between 50 mol% and 95 mol% of the monomer units in the copolymer.

3. The composition according to any one of the preceding claims, wherein, The first 1,3-diene of the copolymer is 1,3-butadiene.

4. The composition according to claim 1, wherein, The 1,3-diene of formula (I) is myrcene, β-farnesene, or a mixture of myrcene and β-farnesene.

5. The composition according to claim 1, wherein, The copolymer contains a first 1,3-diene unit between 1 mol% and 49 mol% of the monomer units of the copolymer, and the copolymer contains a 1,3-diene unit of formula (I) between 1 mol% and 50 mol% of the monomer units of the copolymer.

6. The composition according to claim 1, wherein, The copolymer content is in the range of 20 phr to 90 phr, and the diene elastomer with a diene unit weight content of more than 50% is present in the range of 10 phr to 80 phr.

7. The composition according to claim 1, wherein, Diene elastomers with a diene unit weight content greater than 50% are selected from polybutadiene, natural rubber, synthetic polyisoprene, butadiene copolymers, isoprene copolymers, and mixtures of these elastomers.

8. The composition according to claim 1, wherein, The plasticizing system contains a plasticizer that is liquid at 23°C and a plasticizing resin with a glass transition temperature above 20°C.

9. The composition according to claim 1, wherein, Plasticizers that are liquid at 23°C are selected from liquid diene polymers, polyolefin oils, naphthenic oils, paraffin oils, DAE oils, MES oils, TDAE oils, RAE oils, TRAE oils, SRAE oils, mineral oils, vegetable oils, ether plasticizers, ester plasticizers, and mixtures thereof.

10. The composition according to claim 1, wherein, The content of the plasticizer, which is liquid at 23°C, ranges from 1 phr to 49 phr.

11. The composition according to claim 1, wherein, Plasticizing resins with a glass transition temperature higher than 20°C are selected from cyclopentadiene homopolymers or copolymers, dicyclopentadiene homopolymers or copolymers, terpene homopolymers or copolymers, C5 fraction homopolymers or copolymers, C9 fraction homopolymers or copolymers, α-methylstyrene homopolymers or copolymers, and mixtures thereof.

12. The composition according to claim 1, wherein, The content of plasticizers with glass transition temperatures above 20°C ranges from 1 phr to 99 phr.

13. An elastomeric laminate comprising at least two adjacent layers: - The first layer is composed of the composition according to any one of claims 1 to 12, - The rubber composition constituting the second layer is based on a diene elastomer and a crosslinking system, wherein the diene elastomer contains more than 50% diene units by weight, wherein... The diene elastomer in the composition of the second layer, with a diene unit weight content greater than 50%, is selected from polybutadiene, natural rubber, synthetic polyisoprene, butadiene copolymer, isoprene copolymer, and mixtures of these elastomers.

14. A rubber article comprising the composition according to any one of claims 1 to 12, or comprising the laminate as defined in claim 13.

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