Rubber composition based on at least one functionalized elastomer comprising polar functional groups and specific phenolic compound

Abstract

To prepare particular crosslinkable compositions that can have improved adhesion properties in a simplified manner relative to the compositions of the prior art.SOLUTION: The invention relates to a rubber composition based on at least one functionalized elastomer comprising polar functional groups, a reinforcing filler and a specific phenolic compound.SELECTED DRAWING: None

Description

[Technical field]

[0001] TECHNICAL FIELD OF THEINVENTION The present invention relates to rubber compositions based on at least one elastomer containing polar functional groups, and also to composites, finished or semi-finished products and tires comprising these compositions. [Background technology]

[0002] Prior Art It is known and has been customary for many years to use rubber compositions in tires whose elastomeric matrix is ​​crosslinked with sulfur, this crosslinking being known as vulcanization. Conventional vulcanization systems use molecular sulfur in combination with at least one vulcanization accelerator. However, it is known that such systems can be detrimental to the processing of the composition before curing due to the phenomenon of scorching. "Scorch" is recalled during the preparation of a rubber composition, resulting in rapid premature vulcanization ("scorching phenomenon"), a very high viscosity in the green state, and ultimately a rubber composition that is difficult to work with and process industrially. As a result, vulcanization systems have been improved over the years, along with processes for preparing rubber compositions, to control the above-mentioned drawbacks. Thus, the compositions often contain, in addition to molecular sulfur or molecular sulfur donors, a combination of vulcanization accelerators, activators, and sometimes vulcanization retarders. Among the various elements of the tire, as is known, the rubber mixture and the reinforcing cords, such as the reinforcing plies containing metal cords, generally require a specific formulation of the rubber mixture, in particular a high content of sulfur and zinc oxide, small amounts of stearic acid, the presence of cobalt salts and, in particular, the use of long lag phase accelerators, in order to ensure the adhesive function. However, these vulcanization systems with a high sulfur content represent great constraints during the manufacture of the semi-finished product, in particular to avoid premature crosslinking. Summary of the Invention [Problem to be solved by the invention]

[0003] Therefore, research has been carried out to develop a crosslinking system that replaces vulcanization and at the same time simplifies the composition and its manufacturing process. Thus, patent application WO2014 / 095586 presents a rubber composition comprising an epoxidized elastomer and a crosslinking system comprising a polycarboxylic acid and an imidazole. However, said document does not address the problem of adhesion. WO2017 / 081387 and WO2017 / 081388 present rubber compositions and composites based on a polymer matrix containing a functional diene polymer. The functional diene polymer has at least one aromatic group substituted with at least two vicinal hydroxyl functional groups. Crosslinking of the rubber composition is carried out with a vulcanization system or a system based on one or more peroxide compounds. Good adhesion properties of the rubber composition to metal are obtained, but require the use of a graft polymer. Continuing their research, Applicant has discovered that it is now possible to prepare certain crosslinkable compositions in a simpler manner than prior art compositions, and that these compositions may have improved adhesive properties. [Means for solving the problem]

[0004] Detailed Description of the Invention The invention, which is described in more detail below, relates to at least one of the embodiments listed in the following points. 1. A method for producing a polymerizable composition comprising the steps of: (a) mixing at least one functionalized elastomer containing a polar functional group, a reinforcing filler, and a polymerizable compound represented by the following general formula (I):

[0005] [ka]

[0006] (In the formula: -G1 represents a hydroxyl, carboxyl or alkoxy group or a hydrogen atom; -G2 represents a hydroxyl group or a hydrogen atom; -G3 represents a hydrogen atom or a group selected from the following groups: hydroxyl, carboxyl, hydrogenocarbonyl, alkyl, carboxylalkyl, carboxylalkenyl, carbonylalkyl, aryl, aryloxy, arylthioxy, arylcarbonyl, amino, aminoalkyl; At least one of the substituents G1 to G3 contains an oxygen atom. and a phenolic compound of the general formula (P1):

[0007] [ka]

[0008] At the same time, it does not contain polycarboxylic acids of A rubber composition wherein A represents a covalent bond or a hydrocarbon-based group containing at least one carbon atom, which may be optionally substituted, and which may be optionally interrupted by one or more heteroatoms. 2. The rubber composition according to the preceding embodiment, wherein G3 represents a hydrogen atom or a group selected from the following groups: hydroxyl, carboxyl, carboxylalkyl, aryl, aryloxy, arylthioxy, arylcarbonyl. 3. The composition according to embodiment 1 or 2, wherein the phenolic compound of general formula (I) comprises at least one aromatic nucleus having at least two hydroxyl functional groups in meta positions relative to each other, and the two positions ortho to at least one of these hydroxyl functional groups are unsubstituted. 4. A composition according to any one of the preceding embodiments, wherein the phenolic compound of general formula (I) has at least three hydroxyl functional groups, preferentially in meta positions relative to each other. 5. The composition of the immediately preceding embodiment, wherein the two positions ortho to each hydroxyl functional group of the phenolic compound of general formula (I) are unsubstituted. 6. The composition of embodiment 1, wherein G3 represents a group selected from the following groups: aryl, aryloxy, arylthioxy, arylcarbonyl. 7. The composition according to the immediately preceding embodiment, wherein at least two aromatic nuclei of the phenolic compound of general formula (I) have at least two hydroxyl functional groups in meta positions relative to each other, and at least one of the two positions ortho to at least one of these hydroxyl functional groups of at least one aromatic nucleus is unsubstituted. 8. The composition of the immediately preceding embodiment, wherein the two positions ortho to at least one hydroxyl functional group of each aromatic nucleus of the phenolic compound of general formula (I) are unsubstituted. 9. The composition of embodiment 1, wherein the phenolic compound of general formula (I) is selected from the group consisting of resorcinol, phloroglucinol, 2,2',4,4'-tetrahydroxydiphenyl sulfide, 2,2',4,4'-tetrahydroxybenzophenone, and mixtures of these compounds. 10. A composition according to any one of the preceding embodiments, comprising at least two phenolic compounds of general formula (I), preferentially at least one of the two phenolic compounds comprising at least two hydroxyl functional groups.

[0009] 11. The composition of any one of the preceding embodiments, also comprising at least one polyaldehyde. 12. The composition of any one of the preceding embodiments, wherein the functionalized elastomer is selected from the group consisting of functionalized diene elastomers, functionalized olefin elastomers, and mixtures thereof. 13. The composition according to the immediately preceding embodiment, wherein the functionalized elastomer is a highly unsaturated diene elastomer, preferentially selected from the group consisting of natural rubbers (NR), synthetic polyisoprenes (IRs), polybutadienes (BRs), butadiene copolymers, isoprene copolymers and mixtures of these elastomers. 14. The composition of the immediately preceding embodiment, wherein the butadiene and isoprene copolymers are selected from the group consisting of butadiene / styrene copolymers (SBRs), isoprene / butadiene copolymers (BIRs), isoprene / styrene copolymers (SIRs), isoprene / butadiene / styrene copolymers (SBIRs), and mixtures of said copolymers. 15. A composition described in any one of the previous embodiments, wherein the polar functional group of the functionalized elastomer contains at least one atom selected from halogen, oxygen, and nitrogen. 16. The composition according to the immediately preceding embodiment, wherein the polar functional group of the functionalized elastomer comprises at least one group selected from hydroxyl, carbonyl, imine and epoxy groups, preferably primary aldimine, aldehyde and epoxy groups, preferentially epoxy groups. 17. The composition of any one of the preceding embodiments, wherein the composition is free of cobalt salts or contains less than 1 phr of cobalt salts. 18. A rubber composition according to any one of the preceding embodiments, wherein the composition is free of zinc or zinc oxide or contains only very small amounts of zinc or zinc oxide, preferentially less than 1 phr, preferably less than 0.5 phr and even more preferentially less than 0.2 phr. 19. The rubber composition of any one of the preceding embodiments, wherein the reinforcing filler comprises carbon black, silica, or a mixture of carbon black and silica. 20. The rubber composition of any one of the preceding embodiments, wherein the reinforcing filler content is between 20 phr and 200 phr.

[0010] 21. A composite material based on at least one reinforcing element and the composition according to any one of the preceding embodiments. 22. The composite material of the immediately preceding embodiment, wherein the reinforcing element includes a metal surface. 23. The composite material of the immediately preceding embodiment, wherein the metal surface of the reinforcing element comprises a metal selected from the group consisting of iron, copper, zinc, tin, aluminum, cobalt, nickel, and alloys containing at least one of these metals. 24. The composite material of the immediately preceding embodiment, wherein the metal of the metal surface is iron, copper, tin, zinc, or an alloy containing at least one of these metals. 25. The composite material of the immediately preceding embodiment, wherein the metal of the metal surface is brass or steel. 26. A finished or semi-finished product comprising the composition according to any one of embodiments 1 to 20 or the composite material according to any one of embodiments 21 to 25. 27. A tire comprising the composition according to any one of embodiments 1 to 20 or the composite material according to any one of embodiments 21 to 25. 28. A tire comprising an inner layer comprising the composition of any one of embodiments 1-20 or the composite material of any one of embodiments 21-25. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] definition The expression "composition based on" should be understood to mean a composition comprising a mixture and / or in situ reaction products of the various components used, some of which can and / or are intended to react with one another, at least in part, during the various stages of the preparation of the composition; the composition may therefore be totally or partially crosslinked or non-crosslinked. For the purposes of the present invention, the expression "parts by weight per 100 parts by weight of elastomer" (or phr) should be understood to mean parts by weight per 100 parts by mass of elastomer. In this text, all percentages expressed are percentages by weight, unless expressly stated otherwise. Furthermore, any interval of values ​​expressed as "between a and b" denotes a range of values ​​greater than a to less than b (i.e., excluding the limits a and b), whereas any interval of values ​​expressed as "from a to b" means a range of values ​​extending from a to b (i.e., including the precise limits a and b). The carbon-containing compounds referred to in this description are of fossil or biological origin. If of biological origin, they may be partially or entirely derived from biomass or may be obtained from renewable starting materials derived from biomass. Polymers, plasticizers, fillers, etc. are of particular relevance.

[0012] Functionalized Elastomers The term "functionalized elastomer or rubber containing polar functional groups (these two terms are, as known, synonymous and interchangeable)" means any type of elastomer within the meaning known to those skilled in the art, whether it is a homopolymer or a block, statistical or other copolymer, that has elastomeric properties that are functionalized, i.e. that it has functional groups selected from polar functional groups. The rubber composition of the present invention may contain only one functionalized elastomer or a mixture of several functionalized elastomers (hence the singular "functionalized elastomer" would mean all of the functionalized elastomers of the composition), which may be used in combination with any type of non-functionalized elastomer, such as diene elastomers, or elastomers other than diene elastomers. The functionalized elastomer is predominant in the rubber composition of the present invention, that is, it is the only elastomer or it is the elastomer that constitutes the greatest amount by weight of all the elastomers in the composition.

[0013] According to a preferred embodiment of the invention, the rubber composition comprises from more than 50 to 100 phr, preferably from 70 to 100 phr, of a functionalized elastomer as a blend with 0 to 50 phr, preferably from 0 to 30 phr, of one or more other non-functionalized elastomers in small amounts. According to another preferential embodiment of the invention, the composition comprises, for every 100 phr of elastomers in total, one or more functionalized elastomers containing polar functional groups. The functionalized elastomer is preferentially selected from the group consisting of functionalized diene elastomers, functionalized olefin elastomers and mixtures thereof. Preferentially, the functionalized elastomer is selected from functionalized olefin elastomers and mixtures thereof. According to another preferential variant of the invention, the functionalized elastomer is selected from functionalized diene elastomers and mixtures thereof.

[0014] The glass transition temperatures Tg of the elastomers mentioned in this text are measured in known manner by DSC (Differential Scanning Calorimetry), for example according to standard ASTM D3418 of 1999, unless otherwise indicated. Size exclusion chromatography or SEC is used to determine the macrostructure of polymers. SEC allows the separation of macromolecules in solution according to their size through a column packed with a porous gel. The macromolecules are separated according to their hydrodynamic volume, with the bulkiest being eluted first. Although not an absolute method, SEC allows understanding of the molar mass distribution of a polymer. The various number average molecular weights (Mn) and weight average molecular weights (Mw) can be determined from commercially available standards and the polydispersity index (PDI=Mw / Mn) can be calculated by "Moore" calibration.

[0015] Polymer preparation: There is no specific treatment of the polymer samples before analysis. The samples are simply dissolved in tetrahydrofuran (THF) containing 1 vol% diisopropylamine, 1 vol% triethylamine and 0.1 vol% distilled water at a concentration of about 1 g / l, and the solution is filtered through a filler with a porosity of 0.45 μm before injection.

[0016] SEC analysis: the equipment used is a Waters Alliance chromatograph. The elution solvent is tetrahydrofuran containing 1 vol% diisopropylamine and 1 vol% triethylamine. The flow rate is 0.7 ml / min, the temperature of the system is 35° C., and the analysis time is 90 min. A set of four Waters columns in series with the trade names Styragel HMW7, Styragel HMW6E, and two Styragel HT6E are used. The volume of the polymer sample solution injected is 100 μl. The detector is a Waters 2410 differential refractometer, and the software for processing the chromatographic data is the Waters Empower system. The calculated average molecular weight is compared to a calibration curve generated from commercially available polystyrene standards in the PSS Ready Cal-Kit.

[0017] -Diene elastomer The term "functionalized diene type elastomer" is believed to be understood to mean an elastomer (i.e. homopolymer or copolymer) derived at least in part from a diene monomer (a monomer having two conjugated or non-conjugated carbon-carbon double bonds), which polymer is functionalized, i.e. has functional groups selected from polar functional groups. The first characteristic of functionalized diene elastomers is therefore that they are diene elastomers. These diene elastomers can be classified into two categories: "essentially unsaturated" or "essentially saturated". The term "essentially unsaturated" generally means that they are derived at least in part from conjugated diene monomers with a content of diene origin units (conjugated dienes) greater than 15% (mol %); therefore, diene elastomers such as butyl rubber or copolymers of dienes and alpha-olefins of the EPDM type do not fall within the above definition and can in particular be described as "essentially saturated" diene elastomers (low or very low content, always less than 15% of diene origin units). The diene elastomers contained in the compositions of the present invention are preferentially essentially unsaturated.

[0018] The term "diene elastomers that can be used in the composition of the invention" refers in particular to the following: (a) any homopolymer of conjugated or non-conjugated diene monomers containing from 4 to 18 carbon atoms; (b) any copolymer of a conjugated or non-conjugated diene monomer containing from 4 to 18 carbon atoms and at least one other monomer; means... The other monomers may be ethylene, olefins or conjugated or non-conjugated dienes. Suitable conjugated dienes include those containing from 4 to 12 carbon atoms, particularly 1,3-dienes, such as, inter alia, 1,3-butadiene and isoprene. Suitable olefins include vinyl aromatic compounds containing from 8 to 20 carbon atoms and aliphatic alpha monoolefins containing from 3 to 12 carbon atoms. Suitable vinyl aromatic compounds include, for example, styrene, ortho, meta or para methylstyrene, the "vinyl toluene" commercial mixture or para (tert-butyl) styrene. Suitable aliphatic alpha mono-olefins include, in particular, acyclic aliphatic alpha mono-olefins containing from 3 to 18 carbon atoms.

[0019] The functionalized diene elastomer is preferably a highly unsaturated diene elastomer, in particular a diene elastomer selected from the group consisting of natural rubber (NR), synthetic polyisoprenes (IRs), polybutadienes (BRs), butadiene copolymers, isoprene copolymers and mixtures of these elastomers, the copolymers being more preferentially selected from the group consisting of butadiene / styrene copolymers (SBRs), isoprene / butadiene copolymers (BIRs), isoprene / styrene copolymers (SIRs), isoprene / butadiene / styrene copolymers (SBIRs) and mixtures of these copolymers. The diene elastomers may be, for example, block, random, sequential or microsequential elastomers and may be prepared in dispersion or in solution; they may be coupled and / or star-branched or functionalized with coupling and / or star-branching or functionalizing agents.

[0020] The following are preferentially suitable: polybutadienes, in particular those with a content of 1,2-units between 4% and 80% or with a content of cis-1,4-units greater than 80%, polyisoprenes, butadiene / styrene copolymers, in particular those with a styrene content by mass of between 5% and 50%, more in particular between 20% and 40%, a content of 1,2-bonds in the butadiene moiety of between 4% and 65% and a content of trans-1,4-bonds of between 20% and 80%, butadiene / isoprene copolymers, in particular those with an isoprene content by mass of between 5% and 90% and a glass transition temperature of -40°C to -80°C, or isoprene / styrene copolymers, in particular those with a styrene content by mass of between 5% and 50% and a Tg of between -25°C and -50°C. In the case of butadiene / styrene / isoprene copolymers, particularly suitable are those having a styrene content by mass of between 5% and 50%, more particularly between 10% and 40%, an isoprene content by mass of between 15% and 60%, more particularly between 20% and 50%, a butadiene content by mass of between 5% and 50%, more particularly between 20% and 40%, a content of 1,2-units in the butadiene moiety of between 4% and 85%, a content of trans-1,4-units in the butadiene moiety of between 6% and 80%, a content of 1,2-units plus 3,4-units in the isoprene moiety of between 5% and 70% and a content of trans-1,4-units in the isoprene moiety of between 10% and 50%, and more generally those having a Tg of between -20°C and 70°C.

[0021] -Olefin elastomer The term "functionalized olefin type elastomer" is considered to be understood to mean an elastomer having a functional group selected from polar functional groups, the elastomer chain being a carbon chain mainly comprising olefin monomer units represented by O. Monomer O may originate from any olefin known to those skilled in the art, such as ethylene, propylene, butylene or isobutylene, which monomers may optionally be substituted with linear or branched alkyl groups. Preferentially, O is an ethylene unit [-CH2-CH2-], and in this preferential case the functionalized olefin elastomer is a functionalized ethylene elastomer. The molar content of O is greater than 50%. More precisely, the molar content of O is between 50% and 95%, preferentially between 65% and 85%. For the purposes of the present invention, olefin elastomers are therefore copolymers which also contain 5 to 50 mol % of non-olefinic units, i.e. units other than O.

[0022] These non-olefinic units are composed partly or entirely of units carrying the functional groups designated R necessary for the requirements of the present invention. The content (mol %) of units R in said functionalized olefinic elastomers can vary widely depending on the specific embodiment of the invention, but is preferably in the range of 0.1% to 50%, preferentially in the range of 0.3% to 50%, even more preferentially in the range of 0.3% to 30% and very preferentially in the range of 2.5% to 30%. When the content of units R is less than 0.1%, there is a risk that the targeted technical effect is insufficient, while above 50%, the elastomer is no longer predominantly olefinic. If not all the non-olefinic units are units R, other units, designated A', are present in the carbon chain, so that the total molar content accounted for by monomers O, R and A' is equal to 100%. The non-olefinic monomers useful in the preparation of functionalized olefinic elastomers may be selected from non-olefinic monomers that do not introduce unsaturation and monomers (other than diene monomers) that, when polymerized, introduce unsaturation carried along the elastomeric chain. The non-olefinic monomers that do not introduce unsaturation are essentially vinyl and acrylic / methacrylic monomers, for example, they can be chosen from styrene, vinyl acetate, vinyl alcohol, acrylonitrile, methyl acrylate or methyl methacrylate, which may optionally be substituted with alkyl or aryl groups or other functionalizing groups. Also useful, for example, for preparing olefin elastomers having unsaturation by copolymerization are all those known to those skilled in the art to form unsaturated elastomers, such as dicyclopentadienyloxyethyl methacrylate.

[0023] -polar functional group According to the invention, the rubber composition is based on at least one functionalized elastomer containing polar functional groups. The presence of polar functional groups in the elastomer makes it possible to crosslink it with the phenolic compounds of general formula (I) independently of the rest of the structure of the elastomer, for example dienes or olefins, and thus to have improved adhesive properties overall. For purposes of the present invention, the term "polar functional group" refers to a functional group that has a non-zero dipole moment due to asymmetrically arranged opposite charges (i.e., partial positive and partial negative charges). The polar bond in a polar functional group can be, for example, a bond between a carbon atom and another atom that has a relatively high electronegativity, such as O, N, F, and Cl. Preferably, the polar functional group of the functionalized elastomer comprises at least one atom selected from halogen, oxygen and nitrogen. Preferably, the polar functional group of the functionalized elastomer comprises a group selected from hydroxyl, carbonyl, imine and epoxy groups. Hydroxyl, carbonyl, imine and epoxy groups are well known to those skilled in the art. The term "hydroxyl group" refers to a group of formula -OH. The term "carbonyl group" refers to a group containing a carbon atom bonded to an oxygen atom through a double bond. The term "imine group" refers to a group containing a carbon atom bonded to a nitrogen atom through a double bond. The term "epoxy group" refers to a group containing an oxygen atom bridged across a carbon-carbon bond. The functional groups present in the elastomers may be obtained by copolymerization or post-polymerization modification, as known to those skilled in the art, and may be directly borne by the backbone of the chain or may be borne by side groups depending on the method of preparation. Preferably, the functionalized elastomer of the rubber composition of the present invention comprises at least one group selected from primary aldimine, aldehyde and epoxy groups, preferentially epoxy groups. The term "primary aldimine" means a monovalent radical of imine type of formula -(CH)=NH. The term "aldehyde" means a monovalent radical of carbonyl type of formula -(CH)=O.

[0024] -Epoxide-functionalized elastomers The functionalized elastomers containing polar functional groups are preferably functionalized elastomers containing epoxy groups. Functionalized elastomers containing epoxy groups, called without preference "epoxidized elastomers" or "epoxide-functionalized elastomers", are, as is known, solid at room temperature (20° C.); the term "solid" refers to any material that does not have the capacity to ultimately assume the shape of the container in which it is located, by itself, under the influence of gravity and at room temperature (20° C.), after a period of at least 24 hours. The degree of epoxidation (mol%) of the epoxidized elastomer can vary widely depending on the specific embodiment of the invention, but is preferably in the range of 0.1% to 80%, preferentially in the range of 0.1% to 50%, and even more preferentially in the range of 0.3% to 50%. When the degree of epoxidation is less than 0.1%, there is a risk that the targeted technical effect is insufficient, while above 80%, the inherent properties of the polymer deteriorate. For all these reasons, the degree of functionalization, and in particular the degree of epoxidation, is more preferentially in the range of 0.3% to 30%, and even more preferentially in the range of 2.5% to 30%.

[0025] Epoxidized diene elastomers can be obtained, for example, by epoxidation of equivalent non-epoxidized diene elastomers, as is known, for example by processes based on chlorohydrins or bromohydrins or by processes based on hydrogen peroxide, alkyl hydroperoxides or peracids (for example peracetic acid or performic acid); see in particular Kautsch. Gummi Kunstst., 2004, 57(3), 82. Epoxy functions are then present in the polymer chain. Mention may in particular be made of epoxidized natural rubber (abbreviated ENR), which is sold, for example, by the company Guthrie Polymer under the trade names ENR-25 and ENR-50 (with epoxidation degrees of 25% and 50%, respectively). Epoxidized BRs are also known per se and are sold, for example, by the company Sartomer under the trade name Poly Bd (for example Poly Bd 605E). Epoxidized SBRs can be prepared by epoxidation techniques well known to those skilled in the art. Diene elastomers containing epoxy groups are described, for example, in US 2003 / 120007 or EP 0763564, and in US 6903165 or EP 1403287. Preferentially, the epoxidized diene elastomer is selected from the group consisting of epoxidized natural rubbers (NRs) (abbreviated as ENRs), epoxidized synthetic polyisoprenes (IRs), epoxidized polybutadienes (BRs) preferentially having a content of cis-1,4-bonds greater than 90%, epoxidized butadiene / styrene copolymers (SBRs) and mixtures of these elastomers.

[0026] Epoxidized diene elastomers may have epoxy side functionalities. In this case, they can be obtained by post-polymerization modification (see, for example, J. Appl. Polym. Sci., 1999, 73, 1733) or by radical copolymerization of diene monomers with epoxy functional groups, in particular methacrylic acid esters containing epoxy functional groups, such as glycidyl methacrylate (this radical polymerization, in particular in bulk, solution or dispersion, in particular in dispersion, emulsion or suspension polymerization, is well known to those skilled in the art of polymer synthesis; for example, reference may be made to Macromolecules 1998, 31, 2822) or by using nitrile oxides with epoxy functionalities. For example, US2011 / 0098404 describes the emulsion copolymerization of 1,3-butadiene, styrene and glycidyl methacrylate. Epoxidized olefin elastomers and the processes for obtaining them are well known to those skilled in the art. Olefin elastomers containing epoxy groups are described, for example, in EP 0247580 and US 5576080. The company Arkema markets epoxidized polyethylenes under the trade names Lotader AX8840 and Lotader AX8900.

[0027] The epoxy functional groups may be directly supported by the carbon backbone, and are then mainly obtained after copolymerization by epoxidation of the carbon-carbon double bonds originally present. This epoxidation of unsaturated polymers is well known to those skilled in the art and can be carried out, for example, by processes based on chlorohydrins or bromohydrins, by direct oxidation processes or by processes based on hydrogen peroxide, alkyl hydroperoxides or peracids, such as peracetic acid or performic acid. The epoxy functionality may be pendant, then already present in the monomer that participates in the copolymerization with the olefin (this monomer may be, for example, glycidyl methacrylate, allyl glycidyl ether or vinyl glycidyl ether), or obtained by post-copolymerization modification of the pendant functionality. Epoxidized olefin elastomers very often have a Tg that is negative (ie, less than 0° C.). The epoxidized olefin elastomer has a number average molecular weight (Mn) of at least 10,000 g / mol, preferentially at least 15,000 g / mol, and not more than 1,500,000 g / mol. The polydispersity index PDI, which is equal to Mw / Mn (Mw is the weight average molecular weight), is between 1.05 and 11.00.

[0028] Preferably, and in summary, the olefin elastomer containing epoxy functionality thus contains at least 50% (by mole) of olefin monomer units and is a copolymer with several different monomers, of which there are two or more, preferentially between 2 and 5, and even more preferentially two or three. This copolymer can be obtained by copolymerization or by post-polymerization modification of the elastomer. The epoxy functionality present in the olefin copolymer, obtained by copolymerization or by post-polymerization modification, will be borne directly by the backbone of the chain or by side groups, depending on the preparation method, for example by epoxidation or any other modification of the diene functions present in the elastomer chain after copolymerization.

[0029] Reinforcing filler Any type of reinforcing filler known for its ability to reinforce rubber compositions that may be used in the manufacture of tires may be utilized, for example, organic fillers such as carbon black, reinforcing inorganic fillers such as silica, or blends of these two types of fillers, particularly blends of carbon black and silica. All carbon blacks are suitable as carbon blacks, in particular blacks of the HAF, ISAF or SAF type usually used in tires ("tire grade" blacks). Among the latter, more particular mention is made of reinforcing carbon blacks of the 100, 200 or 300 series (ASTM grades), such as N115, N134, N234, N326, N330, N339, N347 or N375 blacks, or, depending on the targeted application, blacks of higher series (for example N660, N683 or N772). The carbon blacks may, for example, already be incorporated in the isoprene elastomer in the form of a masterbatch (see, for example, patent applications WO97 / 36724 and WO99 / 16600). The BET specific surface area of ​​the carbon black is measured according to standard D6556-10 [multipoint (minimum 5 points) method - gas: nitrogen - relative pressure P / P0 range: 0.1 to 0.3].

[0030] In the present patent application, the term "reinforcing inorganic filler" should be understood to mean any inorganic or mineral filler, also known as "white filler", "clear filler" or "non-black filler" as opposed to carbon black (irrespective of its color and its origin, natural or synthetic), which by definition is capable of reinforcing by itself, without any means other than intermediate coupling agents, the rubber composition intended for tire manufacture, i.e. capable of replacing normal tire grade carbon black in its reinforcing role; such fillers are generally characterized, as is known, by the presence of hydroxyl (-OH) groups on their surface. Mineral fillers of the siliceous type, in particular silica (SiO2), or of the aluminous type, in particular alumina (Al2O3), are particularly suitable as reinforcing inorganic fillers. The silica used may be any reinforcing silica known to those skilled in the art, in particular both 450m 2 / g, preferably 30 to 400m 2The silica may be any precipitated or fumed silica having a BET surface area and a CTAB specific surface area of ​​0.1 g / g. Highly disperse precipitated silicas (HDSs) include, for example, Ultrasil 7000 and Ultrasil 7005 silicas from Degussa, Zeosil 1165MP, 1135MP and 1115MP silicas from Rhodia, Hi-Sil EZ150G silica from PPG, Zeopol 8715, 8745 and 8755 silicas from Huber or silicas with high specific surface area as described in patent application WO 03 / 16837.

[0031] The physical state in which the reinforcing inorganic filler is provided is not important, whether it is in the form of powder, micropearls, granules, beads or any other suitable densified form. It goes without saying that the term "reinforcing inorganic filler" also refers to mixtures of different reinforcing inorganic fillers, in particular highly disperse siliceous and / or aluminous fillers. The reinforcing inorganic filler used, especially when it is silica, is preferably 45 ml 2 / g and 400m 2 / g, and more preferentially 60m 2 / g and 300m 2 / g. Preferentially, the total content of reinforcing fillers (carbon black and / or reinforcing inorganic fillers, such as silica) is between 20 and 200 phr, more preferentially between 30 and 150 phr, the optimum content varying, as is known, depending on the specific term targeted: for example, the reinforcement level expected for bicycle tyres is naturally lower than that required for tyres capable of sustained high speed travel, such as motorcycle tyres, passenger car tyres or tyres for utility vehicles, such as heavy duty vehicles.

[0032] According to a preferred embodiment of the invention, between 30 and 150 phr, more preferentially between 50 and 120 phr, of organic fillers, in particular carbon black, and optionally reinforcing fillers including silica are used; when silica is present, it is preferred to use it in a content of less than 20 phr, more preferentially less than 10 phr (for example between 0.1 and 10 phr). This preferred embodiment is particularly preferred when the main elastomer of the composition is epoxidized isoprene rubber, more particularly epoxidized natural rubber. Alternatively, according to another preferred embodiment of the invention, between 30 and 150 phr, more preferentially between 50 and 120 phr, of a reinforcing filler is used, which comprises an inorganic filler, in particular silica, and optionally carbon black; when carbon black is present, it is preferred to use it in a content of less than 20 phr, more preferentially less than 10 phr (for example between 0.1 and 10 phr). This preferred embodiment is also preferred in particular when the main elastomer of the composition is epoxidized isoprene rubber, more particularly epoxidized natural rubber.

[0033] Preferably, the rubber composition of the present invention is free of coupling agents (or binders). The term "composition free of a certain compound" means that the composition does not contain this compound intentionally introduced into the composition, and if this compound is present, it is present, for example, in the form of traces related to the manufacturing process of the composition or in the form of the elements of which it is composed. For example, a composition free of this compound contains this compound in an amount of 0.2 phr or less, preferably 0.1 phr or less, preferably 0.05 phr or less. Those skilled in the art will appreciate that other natural, particularly organic, reinforcing fillers can be used as equivalent fillers to the reinforcing inorganic fillers described in this section, provided that the reinforcing fillers are either covered with an inorganic layer such as silica or contain functional sites, particularly hydroxyl sites, on their surface that allow for the establishment of bonds between the filler and the elastomer in the presence or absence of a coating or coupling agent.

[0034] Phenolic Compounds The composition of the present invention is a composition represented by the following general formula (I): The compound contains at least one phenol compound selected from the group consisting of phenols.

[0035] [ka]

[0036] (In the formula: -G1 represents a hydroxyl, carboxyl or alkoxy group or a hydrogen atom; -G2 represents a hydroxyl group or a hydrogen atom; -G3 represents a hydrogen atom or a group selected from the following: hydroxyl, carboxyl, hydrogenocarbonyl, alkyl, carboxylalkyl, carboxylalkenyl, carbonylalkyl, aryl, aryloxy, arylthioxy, arylcarbonyl, amino, aminoalkyl; At least one of the substituents G1 to G3 contains an oxygen atom. The compound contains at least one phenol compound selected from the group consisting of phenols.

[0037] In the present description, the term "phenolic compound" refers to an aromatic compound of general formula (I). The term "carboxyl group" or "carboxylic acid functional group" means a group of formula -COOH, where a carbon atom is attached to an oxygen atom through a double bond and to a hydroxyl group -OH through a single bond. The term "hydrogenocarbonyl group" means a group of formula -CHO, where a carbon atom is attached to an oxygen atom through a double bond and to a hydrogen atom through a single bond. The term "carboxyalkenyl group" means a group of formula -(CnH2n-2)-COOH. The term "carbonylalkyl group" means a group of formula -(CnH2n)-CHO. The term "aryloxy group" means a group of the general formula -O-aryl, where the aryl group is bonded to an oxygen atom. The term "arylthioxy group" means a group of the general formula -S-aryl, where the aryl group is bonded to a sulfur atom. The term "arylcarbonyl group" means a group of the general formula -CO-aryl, where the aryl group is bonded to a carbonyl group. The term "amino group" means a group of formula -NH2. The term "aminoalkyl group" refers to a group of the formula -C n H 2n It means the group -NH2.

[0038] In the above definitions, n is advantageously an integer between 1 and 15, preferentially between 1 and 10, very preferentially between 1 and 5 and preferably between 1 and 3. Preferably, G3 represents a hydrogen atom or a group selected from the following groups: hydroxyl, carboxyl, carboxylalkyl, aryl, aryloxy, arylthioxy, arylcarbonyl. Preferably, the phenolic compound of general formula (I) comprises at least one aromatic nucleus having at least two hydroxyl functional groups in meta positions relative to each other, and the two positions ortho to at least one of the hydroxyl functional groups are unsubstituted. Preferentially, the phenolic compounds of general formula (I) have at least three hydroxyl functional groups, preferably in meta positions relative to one another, and the two positions ortho to each hydroxyl functional group are preferentially unsubstituted. In a preferred arrangement, G3 represents a group selected from the following groups: aryl, aryloxy, arylthioxy, arylcarbonyl. Preferably, according to this arrangement, at least two aromatic nuclei of the phenolic compound of general formula (I) have at least two hydroxyl functional groups in meta positions relative to each other, and at least one aromatic nucleus, preferably the two positions ortho to at least one of the hydroxyl functional groups of each aromatic nucleus, is unsubstituted. Very preferably, the phenolic compound of general formula (I) is selected from the group consisting of resorcinol, phloroglucinol, 2,2',4,4'-tetrahydroxydiphenyl sulfide, 2,2',4,4'-tetrahydroxybenzophenone and mixtures of these compounds.

[0039] The rubber composition of the invention advantageously comprises from 0.1 to 60 phr, preferably from 0.1 to 50 phr, preferably from 0.1 to 30 phr, very preferably from 2 to 30 phr, very preferably from 4 to 30 phr of phenolic compounds. Below 0.1 phr, the phenolic compounds have no noticeable effect on the crosslinking of the rubber composition of the invention. The person skilled in the art will adjust the exact content as a function of the properties desired for the crosslinkable rubber composition, in particular its stiffness and its hysteresis loss. Surprisingly, the presence of at least one compound of general formula (I) makes it possible to crosslink the rubber composition of the invention. It is also surprising that a very good adhesion of the composition of the invention to the reinforcing cord is obtained, especially when several phenolic compounds of general formula (I) are used.Preferably, the composition of the invention therefore comprises at least two phenolic compounds of general formula (I), at least one of these two phenolic compounds preferentially comprising at least two hydroxyl functions.

[0040] aldehyde Preferably, the compositions of the present invention may comprise an aldehyde compound as defined in patent applications WO2016 / 116468, WO2017 / 103403, WO2017 / 103404 and WO2017 / 103406 (in these patent applications, the compounds designated as aldehyde of formula (A), compound of formula W5, aldehyde of formula W and compound of formula W2, respectively). Very preferably, the composition of the invention may comprise an aldehyde selected from the group consisting of 1,3-benzenedicarboxaldehyde, 1,4-benzenedicarboxaldehyde and mixtures thereof, preferentially 1,4-benzenedicarboxaldehyde. The addition of this compound makes it possible to modify the stiffness of the composition of the invention, once it has been crosslinked, without adversely affecting its hysteresis properties.

[0041] Various additives The rubber composition of the invention may comprise all or some of the usual additives known to those skilled in the art and generally used in rubber compositions for tires, and in particular in the composition of the inner layer as defined hereinafter in this patent application, such as plasticizers (plasticizing oils and / or plasticizing resins), reinforcing or non-reinforcing fillers other than those mentioned above, pigments, protective agents such as antiozonant waxes, chemical antiozonants, antioxidants, antifatigue agents or reinforcing resins (as described, for example, in patent application WO 02 / 10269). These compositions may also contain processing aids that, as is known, improve the ability of the composition to be processed in the raw state, thanks to an improved dispersion of the filler in the rubber matrix and a reduced viscosity of the composition; these agents are, for example, hydrolyzable silanes, such as alkylalkoxysilanes (for example octyltriethoxysilane or silane octeo), polyols, polyethers, primary, secondary or tertiary amines, or hydroxylated or hydrolyzable polyorganosiloxanes. Surprisingly, the compounds of general formula (I) make it possible to crosslink the rubber composition of the invention, i.e., they make it possible to harden the composition and increase its elasticity by curing it. Thus, the rubber composition of the present invention is free of the crosslinking systems normally associated with functionalized elastomers containing polar functional groups. In particular, the rubber composition of the present invention does not simultaneously contain an alkyl-imidazole and a polycarboxylic acid of the following general formula (P1):

[0042] [ka]

[0043] A represents a covalent bond or a hydrocarbon-based group containing at least one carbon atom, preferentially from 1 to 1800 carbon atoms, which may be optionally substituted and which may be optionally interrupted by one or more heteroatoms. Preferably, the rubber composition of the invention comprises less than 20 phr, preferentially less than 10 phr, very preferentially less than 2 phr of polycarboxylic acid of general formula (P1), very preferably does not comprise any polycarboxylic acid of general formula (P1). Preferably, the rubber composition of the invention comprises less than 2 phr, preferentially less than 1 phr, very preferentially less than 0.2 phr of alkylimidazole, very preferably does not comprise any alkylimidazole. Preferably, the rubber composition of the present invention contains no vulcanization system or less than 1 phr, preferably less than 0.5 phr and more preferentially less than 0.2 phr of vulcanization system. Thus, the rubber composition of the present invention contains preferentially no molecular sulfur or less than 1 phr, preferably less than 0.5 phr and more preferentially less than 0.2 phr of molecular sulfur. Likewise, the composition contains preferentially no vulcanization accelerator or activator known to the person skilled in the art or less than 1 phr, preferably less than 0.5 phr and more preferentially less than 0.2 phr of vulcanization accelerator or activator. In particular, the rubber composition of the present invention contains preferentially no zinc or zinc oxide or less than 1 phr, preferably less than 0.5 phr and very preferably less than 0.2 phr of zinc or zinc oxide. Likewise, the rubber composition of the invention is preferentially free of cobalt salts known to those skilled in the art and whose effect is the improvement of adhesion, or contains less than 1 phr, preferably less than 0.5 phr, even more preferentially less than 0.2 phr and very preferentially less than 0.1 phr of cobalt salts known to those skilled in the art. Thus, surprisingly, very good adhesion of the compositions of the invention to the reinforcing cords is obtained without the need for the use of cobalt salts.

[0044] Preparation of Rubber Composition The rubber compositions of the present invention can be prepared in a suitable mixer using two successive preparation steps well known to those skilled in the art: - the first stage of thermomechanical working or compounding, which can be carried out in a single thermomechanical step, during which all the necessary components, in particular the elastomer matrix, the filler and, optionally, various other additives, are introduced into a suitable mixer, for example a standard internal mixer (for example of the "Banbury" type). The incorporation of the filler into the elastomer can be carried out in one or several batches during thermomechanical compounding. For example, when the filler is already incorporated into the elastomer, wholly or partially, in the form of a masterbatch, as described in patent applications WO 97 / 36724 and WO 99 / 16600, the masterbatch is directly compounded, incorporating, if necessary, other elastomers or fillers not in the form of a masterbatch, present in the composition, and also, optionally, various other additives. The first stage is carried out at elevated temperatures up to a maximum temperature of between 110° C. and 190° C., preferably between 130° C. and 180° C., for a period generally between 2 and 10 minutes.

[0045] - a second mechanical operation, carried out in an external mixer, for example an open mill, after cooling the mixture obtained during the first stage to a lower temperature, typically below 110°C, for example between 40°C and 100°C. The phenolic compound is then incorporated and the whole is mixed for a few minutes, for example between 2 and 15 minutes. The final composition thus obtained may subsequently be calendered, for example in the form of sheets or plaques, in particular for laboratory characterization, or may be extruded in the form of rubber semi-finished products (or profiled elements) for use in tire production. The composition may be in either the green state (before crosslinking) or in the cured state (after crosslinking), or may be a semi-finished product that can be used in tires.

[0046] composite material The present invention also relates to a composite material based on at least a reinforcing element and the rubber composition of the invention. The expression composite material "based on at least reinforcing elements and the composition of the invention" should be understood to mean a composite material comprising reinforcing elements and said composition, and that the composition has been able to react with the surface of the reinforcing elements during the various stages of the manufacture of the composite material, in particular during or before crosslinking of the composition. The reinforcing elements are thread-like elements. They may be entirely or partially metallic or woven. The term "thread-like element" refers to an element having a length of at least 10 times the largest dimension of its cross section, regardless of the shape of said cross section: circular, elliptical, rectangular, polygonal, in particular rectangular or square or oval. In the case of a rectangular cross section, the thread-like element has a band shape. In particular, the reinforcing elements may be of textile nature, i.e. made of organic material, in particular polymeric material, or inorganic material, such as glass, quartz, basalt or carbon. The polymeric material may be of thermoplastic type, such as aliphatic polyamides, in particular polyamide 6,6, and polyesters, in particular polyethylene terephthalate. The polymeric material may be of non-thermoplastic type, such as aromatic polyamides, in particular aramids, and cellulose, natural or artificial, in particular rayon.

[0047] In a particular arrangement, the reinforcing element comprises a metal surface. The metallic surface of the reinforcing element constitutes at least a part, and preferentially the entire surface of said element, intended to be in direct contact with the composition of the invention. Preferably, the reinforcing element is metallic, i.e. it is made of a metallic material. The composite material of the invention covers at least a part of the reinforcing elements, preferentially all of said elements. According to a first variant of the invention, the metal surface of the reinforcing element is made of a material different from the rest of the reinforcing element, in other words the reinforcing element is made of a material that is at least partially, preferentially entirely covered with a metal layer constituting the metal surface, the material that is at least partially, preferentially entirely covered with the metal surface can be metallic or non-metallic, preferably essentially metallic. According to a second variant of the invention, the reinforcing elements are made of one and the same material, in which case they are made of the same metal as the metal of the metal surface.

[0048] According to one embodiment of the present invention, the metal surface comprises a metal selected from the group consisting of iron, copper, zinc, tin, aluminum, cobalt, nickel and alloys comprising at least one of these metals. The alloys may for example be binary or ternary alloys, such as steel, bronze and brass. Preferably, the metal surface comprises a metal selected from the group consisting of iron, copper, tin, zinc and alloys comprising at least one of these metals. Even more preferentially, the metal surface comprises a metal selected from the group consisting of steel, brass (Cu-Zn alloy), zinc and bronze (Cu-Sn alloy), even more preferably from the group consisting of brass and steel. Very preferably, the metal surface is made of brass. When certain metals are exposed to oxidation in contact with ambient air, the metals may become partially oxidized. When the metal surface is made of steel, the steel is preferentially carbon steel or stainless steel. When the steel is carbon steel, its carbon content is preferably between 0.01% and 1.2%, or between 0.05% and 1.2%, or between 0.2% and 1.2%, in particular between 0.4% and 1.1%. When the steel is stainless steel, it preferably contains at least 11% chromium and at least 50% iron.

[0049] According to a preferred embodiment, the composite material is a reinforced product comprising several reinforcing elements as defined above and a calendered rubber in which the reinforcing elements are embedded, the calendered rubber being made of the rubber composition of the invention. According to this embodiment, the reinforcing elements are generally arranged side by side along a main direction. In the application envisaged for tires, the composite material can thus be a component of the tire reinforcement. The composite material of the present invention may be in the raw state (before the rubber composition is crosslinked) or in the cured state (after the rubber composition is crosslinked). The composite material is cured after contacting the reinforcing element with the rubber composition of the present invention. The composite material is produced by the following process: - making two layers of the composition of the invention, - sandwiching the reinforcing element(s) between the two layers by precisely placing the reinforcing element(s) between these two layers, - If necessary, hardening the composite material The present invention can be manufactured by a process including the steps of:

[0050] Alternatively, the composite material may be produced by precisely placing the reinforcing element in a portion of a layer and then folding this layer onto itself to cover the reinforcing element, thus sandwiching the reinforcing element over its entire length or a portion of its length. The layers may be created by calendaring. During curing of the composite, the rubber composition is crosslinked. When the composite material is intended for use as a reinforcing element in a tire, curing of the composite material generally occurs during the curing of the tire casing.

[0051] Finished or semi-finished products and tires The subject of the present invention is also a finished or semi-finished product comprising the composition of the present invention. The finished or semi-finished product may be any article comprising a rubber composition. Examples that may be mentioned in a non-limiting manner include balloons, conveyor belts, shoe soles and pneumatic or non-pneumatic tire casings. Another subject of the invention is a tire, which has the essential feature of comprising the composition or composite of the invention. The tire may be in the green state (before the crosslinking of the rubber composition) or in the cured state (after the crosslinking of the rubber composition). Generally, during the manufacture of a tire, the composition or composite is placed precisely in the structure of the tire in the green state (i.e. before the crosslinking of the rubber composition) and before the step of curing the tire. The invention relates in particular to tyres intended to be fitted to motor vehicles of passenger type, to SUVs (Sports Utility Vehicles), or to two-wheeled vehicles (especially motorcycles), or to aircraft, or to industrial vehicles chosen from trucks, heavy duty vehicles, i.e. subways, buses, heavy road transport vehicles (lorries, tractors, trailers) or off-road vehicles, such as heavy agricultural or construction vehicles.

[0052] Within a tire, three types of regions can be defined: The radially outer region in contact with the surrounding air, which region essentially consists of the tread and the outer sidewall of the tire. The outer sidewall is an elastomeric layer located outside the carcass reinforcement with respect to the internal cavity of the tire, between the crown and the bead, so as to completely or partially cover the area of ​​the carcass reinforcement extending from the crown to the bead. The radially inner region in contact with the inflation gas; this region typically consists of a layer that is leaktight to the inflation gas; this layer is sometimes known as the leaktight inner layer or innerliner. The interior region of the tire, i.e. the region between the outer and inner regions, which includes layers or plies referred to herein as the inner layer of the tire, such as the carcass ply, the tread sublayer, the tire belt ply or any other layer that is not in contact with the ambient or inflating air of the tire. The composition defined in this description is particularly well suited for the inner layer of a tire. The present invention therefore also relates to a tire comprising an inner layer comprising the composition or composite of the present invention. According to the present invention, the inner layer may be selected from the group consisting of carcass ply, crown ply, bead-wire filling, crown foot, decoupling layer, tread underlayer and combinations of these inner layers. Preferably, the inner layer is selected from the group consisting of carcass ply, crown ply, bead-wire filling, crown foot, decoupling layer and combinations of these inner layers. EXAMPLES

[0053] Working Example Measurement method -Tensile test The tests were carried out according to French standard NF T 46-002 of September 1988. All tensile measurements were carried out under standard conditions of temperature (23±2°C) and humidity (50%±5% relative humidity) according to French standard NF T 40-101 (December 1979). At the second elongation (i.e. after accommodation), the nominal secant modulus (or apparent stress, MPa) calculated on the initial cross section of the specimen was measured at elongations of 10% and 100%, respectively, and was calculated as MA 10 and M.A. 100 All these measurements are performed on cured (or crosslinked) specimens. The results are expressed in base 100, with a value of 100 being assigned to the control. A result greater than 100 means that the composition of the example under consideration has a stiffness greater than that of the control.

[0054] -Rolling resistance rating The rolling resistance induced by the test composition is evaluated by measuring the energy loss by measuring the energy restored at the sixth recoil of a sample on which an initial energy has been imposed, at a temperature of 60° C., as described in the standard DIN 53-512 of April 2000. This measurement is designated P60 and is calculated as follows: P60(%)=100×(E0-E1) / E0, where E0 represents the initial energy and E1 represents the restored energy. The smaller this value, the smaller the hysteresis loss the test sample exhibits. The results are expressed on a base 100 basis relative to the control, with values ​​below 100 corresponding to lower energy losses.

[0055] Preparation of Rubber Composition The following procedure is used to prepare the various rubber compositions: the functionalized polymer and then all other components of the mixture except the phenolic compound are continuously introduced into an internal mixer (final degree of filling: about 70% by volume), the initial vessel temperature being about 60° C. Then a thermomechanical work is carried out in one step until a maximum "drop" temperature of 150° C. is reached. The mixture thus obtained is recovered, incorporating the phenolic compound and the whole is cooled while mixing in an external mixer (homofinisher) at 30° C. The compositions prepared are shown in Table 1.

[0056] Preparation of test specimens The rubber compositions thus prepared are used to prepare composite materials in the form of test specimens according to the following protocol. A block of rubber is prepared consisting of two plaques that are added to each other before curing. The two plaques of the block consist of the same rubber composition. During the preparation of the block, a metal reinforcing element is captured between the two plaques in the raw state, equidistant apart and projecting on either side of the plaques, the ends of which have a sufficient length for the subsequent tensile test. The block containing the metal reinforcing element is then placed in a mold adapted to the intended test conditions, at the discretion of the person skilled in the art; by way of example, in the present case, the block is cured at 170° C. under a pressure of 5.5 tons for a time ranging from 50 minutes to 100 minutes depending on the composition. Each metal reinforcing element consists of two steel wires twisted together, 30 / 100 in diameter, containing 0.7% carbon, with a brass coating containing 63% copper.

[0057] Adhesion Test For the conclusion of the hardening, the test specimen thus formed with cross-linked blocks and metal reinforcing elements is placed in the jaws of a tensile testing machine adapted to measure each cross section separately at a given speed and at a given temperature (for example, in the present case at 100 mm / min and at ambient temperature), according to the method described in standard ASTM D 2229-02. The adhesion level is characterized by measuring the "stripping" force required to peel the cross section from the test specimen. The results are expressed on a base 100 basis relative to a control specimen containing metal reinforcing elements of the same properties as those of the specimens examined and containing the rubber composition "T1" shown in Table 1. A value greater than the control specimen value, arbitrarily set at 100, indicates an improved result, ie, a stripping force greater than that of the control specimen. Specimen T0 does not contain any crosslinking system or any phenolic compound. No crosslinking is observed and, as a result, no properties on the cured specimens can be measured. Specimen T1 contains a crosslinking system standard for epoxidized natural rubber compositions. The compositions of the invention are seen to have stiffness and hysteresis loss properties in the cured state which indicate that they are crosslinked. Compositions C2, C5 and C6 which have been adhesion tested also show good adhesive properties.

[0058] [Table 1]

[0059] All compositions are given in phr; -: not determined; nm: not determined (1) Guthrie Polymer's Epoxidized Natural Rubber, ENR-25 (2) N326 (3) N-(1,3-dimethylbutyl)-N-phenyl-para-phenylenediamine (Santoflex 6-PPD from Flexsys) (4) Supplied by Sigma-Aldrich (5) 1-benzyl-2-methylimidazole, CAS=13750-62-4, Sigma-Aldrich

Claims

1. At least one functionalized elastomer containing a polar functional group, a reinforcing filler, and a polymerizable composition according to the following general formula (I): 【Chemistry 1】 (In the formula: -G 1 represents a hydroxyl, carboxyl or alkoxy group or a hydrogen atom; -G 2 represents a hydroxyl group or a hydrogen atom; -G 3 represents a hydrogen atom or a group selected from the following groups: hydroxyl, carboxyl, hydrogenocarbonyl, alkyl, carboxylalkyl, carboxylalkenyl, carbonylalkyl, aryl, aryloxy, arylthioxy, arylcarbonyl, amino, aminoalkyl; - Substituent G 1 ~G 3 At least one of the groups contains an oxygen atom. and a phenolic compound of the general formula (P1): 【Chemistry 2】 At the same time, it does not contain polycarboxylic acids of The rubber composition wherein A represents a covalent bond or a hydrocarbon-based group containing at least one carbon atom, which may be optionally substituted, and which may be optionally interrupted by one or more heteroatoms.

2. G 3 2. The composition of claim 1, wherein represents a hydrogen atom or a group selected from the following groups: hydroxyl, carboxyl, carboxylalkyl, aryl, aryloxy, arylthioxy, arylcarbonyl.

3. 3. The composition according to claim 1 or 2, wherein the phenolic compound of general formula (I) comprises at least one aromatic nucleus having at least two hydroxyl functional groups in meta positions relative to each other and the two positions ortho to at least one of the hydroxyl functional groups are unsubstituted.

4. 4. The composition according to claim 1, wherein the phenolic compound of general formula (I) has at least three hydroxyl functions, preferentially in meta position relative to one another.

5. 5. The composition of claim 4, wherein the two positions ortho to each hydroxyl functional group of the phenolic compound of general formula (I) are unsubstituted.

6. G 3 2. The composition of claim 1, wherein represents a group selected from the following groups: aryl, aryloxy, arylthioxy, arylcarbonyl.

7. 7. The composition of claim 6, wherein at least two aromatic nuclei of the phenolic compound of general formula (I) have at least two hydroxyl functional groups in meta positions relative to each other, and the two positions ortho to at least one of said hydroxyl functional groups of at least one aromatic nucleus are unsubstituted.

8. 8. The composition of claim 7, wherein at least two positions ortho to the hydroxyl functional group of each aromatic nucleus of the phenolic compound of general formula (I) are unsubstituted.

9. 2. The composition according to claim 1, wherein the phenolic compound of general formula (I) is selected from the group consisting of resorcinol, phloroglucinol, 2,2',4,4'-tetrahydroxydiphenyl sulfide, 2,2',4,4'-tetrahydroxybenzophenone and mixtures of these compounds.

10. The composition according to any one of claims 1 to 9, wherein the polar functional group of the functionalized elastomer comprises at least one atom selected from halogen, oxygen and nitrogen.

11. 11. The composition according to claim 10, wherein the polar functional groups of the functionalized elastomer comprise at least one group selected from hydroxyl, carbonyl, imine and epoxy groups, preferably primary aldimine, aldehyde and epoxy groups, preferentially epoxy groups.

12. A composite material based on at least one reinforcing element and a composition according to any one of claims 1 to 11.

13. The composite material of claim 12 , wherein the reinforcing element comprises a metal surface.

14. A finished or semi-finished product comprising a composition according to any one of claims 1 to 11 or a composite material according to any one of claims 12 and 13.

15. A tire comprising a composition according to any one of claims 1 to 11 or a composite material according to any one of claims 12 and 13.

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