POLYMER WITH SPECIFIC N-SUBSTITUTED IMIDAZOLIDINONA-CHANNEL FUNCTIONAL GROUPS

Description

[0001] The present invention relates to new polymers, in particular diene elastomers, modified by a non-associative nitrogen group. These new modified polymers can be used in particular in rubber compositions, in particular intended for the manufacture of tires.

[0002] In the industrial field of objects manufactured from rubber compositions, particularly tires, polymer blends with reinforcing fillers are often used. In order for such compositions to have good properties, ways are constantly being sought to improve the dispersion of the reinforcing fillers within these polymers. Indeed, good dispersion of these fillers within these polymers is often synonymous with low hysteresis and therefore improved rolling resistance when these rubber compositions are used in tires.

[0003] However, improving rolling resistance has been a constant challenge for tire manufacturers since fuel savings and the need to protect the environment have become a priority.

[0004] Many solutions have been proposed to achieve the objective of reducing hysteresis.

[0005] In particular, mention may be made of the modification of the structure of polymers, in particular diene elastomers, at the end of polymerization by means of modifying agents, the aim being to achieve good interaction between the polymer thus modified and the reinforcing filler, whether it is carbon black or a reinforcing inorganic filler such as silica. For example, mention may be made of document EP0778311B1 which describes the use of diene polymers functionalized by a silanol group at the chain end. More recently, patent application WO2009 / 077837A1 describes elastomers functionalized by a silanol group at one chain end and by an amine group at the other chain end. These modified polymers are effective in reducing hysteresis.

[0006] However, tire manufacturers are always looking to reduce the hysteresis of a rubber compound.

[0007] This is the reason why research has been carried out on other polymer modification reactions, in particular diene elastomers, with a view to obtaining rubber compositions having a reduction in hysteresis. In this respect, mention may be made of the use of compounds bearing nitrogenous associative groups comprising at least one unit making them capable of associating with each other by hydrogen bonds to modify the polymers used in the rubber compositions. These modified polymers bearing unsubstituted imidazolidinone functions are described in document WO2019 / 007884A1.

[0008] However, there is a constant need among tire manufacturers to continue to further reduce the hysteresis of rubber compositions and this is the objective of the present invention.

[0009] This aim is achieved in that the applicant has discovered, surprisingly, during its research that a diene elastomer modified by a modifying agent comprising a non-associative nitrogen group of N-substituted imidazolidinone type gives the compositions containing it an unexpected reduction in hysteresis.

[0010] The subject of the invention is a modified polymer obtained by grafting at least one compound of formula (I) onto at least one unsaturation of the chain of an initial polymer in which: A represents an arenediyl ring, optionally substituted by one or more hydrocarbon chains, identical or different, aliphatic, preferably saturated, linear or branched, optionally substituted or interrupted by one or more heteroatoms; E represents a divalent hydrocarbon group optionally comprising one or more heteroatoms; and X denotes a halogen atom, preferably a chlorine atom.

[0011] The modified polymer of the invention comprises at least one N-substituted imidazolidinone group, i.e. a non-associative nitrogen group, along its chain. The modified polymer of the invention has the advantage of giving the compositions containing it a significant reduction in hysteresis, i.e. an improvement in rolling resistance performance. Another subject of the present invention relates to a composition comprising the modified polymer as described above and at least one additive.

[0012] Another subject of the invention relates to a modified polymer as defined above, characterized in that it is further obtained by grafting at least one compound of formula (V) onto at least one other unsaturation of the chain of said initial polymer in which: A1 represents an arenediyl ring, optionally substituted by one or more hydrocarbon chains, identical or different, aliphatic, preferably saturated, linear or branched, optionally substituted or interrupted by one or more heteroatoms; and E1 represents a divalent hydrocarbon group optionally comprising one or more heteroatoms.

[0013] This modified polymer of the invention comprises at least one N-substituted imidazolidinone group, i.e. a non-associative nitrogen group, along its chain and at least one unsubstituted imidazolidinone group, i.e. an associative nitrogen group, along its chain. The modified polymer of the invention has the advantage of conferring on the compositions containing it, surprisingly, an improvement in the raw rigidity / hysteresis compromise.

[0014] Another subject of the present invention relates to a composition comprising at least one modified polymer as defined above and at least one additive.

[0015] A first subject of the invention relates to a modified polymer obtained by grafting at least one compound of formula (I) onto at least one unsaturation of the chain of an initial polymer in which: A represents an arenediyl ring, optionally substituted by one or more hydrocarbon chains, identical or different, aliphatic, preferably saturated, linear or branched, optionally substituted or interrupted by one or more heteroatoms; E represents a divalent hydrocarbon group optionally comprising one or more heteroatoms; and X denotes a halogen atom, preferably a chlorine atom.

[0016] The modified polymer of the invention comprises at least one N-substituted imidazolidinone group, i.e. a non-associative nitrogen group, along its chain. This modified polymer has the advantage of giving the compositions comprising it a reduction in hysteresis, i.e. an improvement in rolling resistance performance.

[0017] In this document, unless expressly stated otherwise, all percentages (%) indicated are percentages (%) by mass.

[0018] On the other hand, any interval of values ​​designated by the expression "between a and b" represents the domain of values ​​going from more than a to less than b (i.e., excluding the limits a and b) while any interval of values ​​designated by the expression "from a to b" means the domain of values ​​going from a to b (i.e., including the strict limits a and b).

[0019] The compounds mentioned in the description may be of fossil or bio-sourced origin. In the latter case, they may be, partially or totally, derived from biomass or obtained from renewable raw materials derived from biomass.

[0020] By "associative group" is meant groups capable of associating in particular with each other by hydrogen, ionic and / or hydrophobic bonds. According to a preferred embodiment of the invention, these are groups capable of associating by hydrogen bonds. When the associative groups are capable of associating by hydrogen bonds, each associative group preferably comprises at least one donor site and one acceptor site with respect to the hydrogen bond so that two identical associative groups are self-complementary and can associate with each other by forming at least two hydrogen bonds. The associative groups according to the invention are also capable of associating by hydrogen, ionic and / or hydrophobic bonds with functions present on fillers, in particular on reinforcing fillers and in particular on inorganic reinforcing fillers, such as silica.

[0021] By "non-associative group" is meant groups which are not capable of associating with each other, in particular by hydrogen, ionic and / or hydrophobic bonds. Preferably, these are groups which are not capable of associating with each other by hydrogen bonds. These groups do not have a donor site and an acceptor site with respect to the hydrogen bond, so that none of these identical groups are self-complementary. They cannot associate with each other by forming at least two hydrogen bonds.

[0022] By "heteroatom", unless otherwise stated, is meant an atom selected from the group consisting of a sulfur atom, an oxygen atom and a nitrogen atom.

[0023] By "modified polymer obtained by grafting" or "polymer modified by grafting" is meant a polymer comprising functions, in particular N-substituted imidazolidinone functions, which have been introduced into the polymer chain. In practice, the modified polymer is obtained by grafting reaction of at least one compound bearing substituted N-imidazolidinone functions and bearing a function capable of forming a covalent bond with an unsaturation of the polymer chain, this function being a nitrile oxide. During the grafting reaction, the nitrile oxide function(s) of the compound to be grafted form covalent bonds with the unsaturation(s) of the polymer chain.

[0024] As is known, a polymer generally comprises at least one main polymer chain. This polymer chain can be called main from the moment when all the other chains of the polymer are considered as pendant chains as mentioned in the document "Glossary of basic terms in polymer science" (IUPAC recommendations 1996), PAC, 1996, 68, 2287, p2294.

[0025] By "unsaturation" is meant a multiple covalent bond between two carbon atoms; this multiple covalent bond may be a carbon-carbon double bond or a carbon-carbon triple bond, preferably a carbon-carbon double bond.

[0026] For the purposes of the present invention, the term "initial polymer chain" means the polymer chain before the grafting reaction; this chain comprising at least one unsaturation capable, more preferably at least two unsaturations capable, of reacting with the compounds having a nitrile oxide function, as described below. The initial polymer is therefore the polymer serving as the starting reagent during the grafting reaction. The grafting reaction makes it possible to obtain a modified polymer from an initial polymer.

[0027] The initial polymer is a diene elastomer.

[0028] By "diene" elastomer (or indistinctly rubber), whether natural or synthetic, must be understood in a known manner an elastomer consisting at least in part (i.e., a homopolymer or a copolymer) of diene monomer units (monomers carrying two carbon-carbon double bonds, conjugated or not).

[0029] These diene elastomers can be classified into two categories: "essentially unsaturated" or "essentially saturated". "Essentially unsaturated" generally means a diene elastomer derived at least in part from conjugated diene monomers, having a content of units or patterns of diene origin (conjugated dienes) which is greater than 15% (mol %); thus, diene elastomers such as butyl rubbers or copolymers of dienes and alpha-olefins such as EPDM do not fall within the preceding definition and can be described in particular as "essentially saturated" diene elastomers (low or very low content of patterns of diene origin, always less than 15%).

[0030] The term diene elastomer capable of being used in the context of the present invention is particularly understood to mean: any homopolymer of a diene monomer, conjugated or not, having from 4 to 18 carbon atoms; any copolymer of a diene, conjugated or not, having from 4 to 18 carbon atoms and at least one other monomer.

[0031] The other monomer can be ethylene, an olefin or a diene, conjugated or not.

[0032] Suitable conjugated dienes are conjugated dienes having 4 to 12 carbon atoms, in particular 1,3-dienes, such as 1,3-butadiene and isoprene.

[0033] Suitable non-conjugated dienes are non-conjugated dienes with 6 to 12 carbon atoms, such as 1,4-hexadiene, ethylidene norbornene, dicyclopentadiene.

[0034] Suitable olefins are vinylaromatic compounds with 8 to 20 carbon atoms and aliphatic α-monoolefins with 3 to 12 carbon atoms.

[0035] Suitable vinyl aromatic compounds are, for example, styrene, ortho-, meta-, para-methylstyrene, the commercial mixture "vinyl-toluene", para-tert-butylstyrene.

[0036] Suitable aliphatic α-monoolefins are, in particular, acyclic aliphatic α-monoolefins having from 3 to 18 carbon atoms.

[0037] More specifically, the diene elastomer can be: any homopolymer of a conjugated diene monomer, in particular any homopolymer obtained by polymerization of a conjugated diene monomer having from 4 to 12 carbon atoms; any copolymer obtained by copolymerization of one or more conjugated dienes with each other or with one or more vinylaromatic compounds having from 8 to 20 carbon atoms; a copolymer of isobutene and isoprene (butyl rubber), as well as the halogenated versions, in particular chlorinated or brominated, of this type of copolymer; any copolymer obtained by copolymerization of one or more dienes, conjugated or not, with ethylene, an α-monoolefin or their mixture such as for example elastomers obtained from ethylene, propylene with a non-conjugated diene monomer of the aforementioned type.

[0038] Preferably, the initial polymer is, preferably a diene elastomer, chosen from the group consisting of ethylene-propylene-diene monomer copolymers (EPDM), butyl rubber (IRR), natural rubber (NR), synthetic polyisoprenes (IR), polybutadienes (BR), butadiene copolymers, isoprene copolymers and mixtures of these elastomers.

[0039] Preferably, the initial polymer is, preferably a diene elastomer, chosen from the group consisting of ethylene-propylene-diene monomer copolymers (EPDM), butyl rubber (IRR), natural rubber (NR), synthetic polyisoprenes (IR), polybutadienes (BR), butadiene-styrene copolymers (SBR), ethylene-butadiene copolymers (EBR), isoprene-butadiene copolymers (BIR) or isoprene-butadiene-styrene copolymers (SBIR), isobutene-isoprene copolymers (butyl rubber - IIR), isoprene-styrene copolymers (SIR) and mixtures of these elastomers.

[0040] Preferably, the initial polymer is, preferably a diene elastomer, chosen from the group consisting of ethylene-propylene-diene monomer copolymers, butyl rubber and the mixture of these rubbers.

[0041] Preferably, the initial polymer is, preferably a diene elastomer, chosen from the group consisting of natural rubber, synthetic polyisoprenes, polybutadienes, butadiene copolymers, isoprene copolymers and mixtures of these elastomers.

[0042] More preferably, the initial polymer is, preferably a diene elastomer, chosen from the group consisting of natural rubber, synthetic polyisoprenes, polybutadienes, butadiene-styrene copolymers, ethylene-butadiene copolymers, isoprene-butadiene copolymers, isoprene-butadiene-styrene copolymers, isobutene-isoprene copolymers, isoprene-styrene copolymers and mixtures of these elastomers.

[0043] Preferably, the initial polymer is, preferably a diene elastomer, chosen from the group consisting of polybutadienes, butadiene copolymers, isoprene copolymers and mixtures of these elastomers.

[0044] More preferably, the initial polymer is a diene elastomer chosen from the group consisting of polybutadienes, butadiene-styrene copolymers, ethylene-butadiene copolymers, isoprene-butadiene copolymers, isoprene-butadiene-styrene copolymers, isobutene-isoprene copolymers, isoprene-styrene copolymers and mixtures of these elastomers.

[0045] Suitable are polybutadienes and in particular those having a content (mol%) of -1,2 units of between 4% and 80% or those having a content (mol%) of cis-1,4 greater than 80%, polyisoprenes, butadiene-styrene copolymers and in particular those having a Tg (glass transition temperature (Tg, measured according to ASTM D3418-08) of between 0°C and -90°C and more particularly between -10°C and -70°C, a styrene content of between 1% and 60% by weight and more particularly between 20% and 50%, a content (mol%) of -1,2 bonds of the butadiene part of between 4% and 75%, a content (mol%) of trans-1,4 bonds of between 10% and 80%, butadiene-isoprene copolymers and in particular those having an isoprene content of between 5% and 90% by weight and a Tg of - 40°C to - 80°C, isoprene-styrene copolymers and in particular those having a styrene content of between 5% and 50% by weight and a Tg of between - 5 C and - 50°C.In the case of butadiene-styrene-isoprene copolymers, those having a styrene content of between 5% and 50% by weight and more particularly of between 10% and 40%, an isoprene content of between 15% and 60% by weight and more particularly of between 20% and 50%, a butadiene content of between 5% and 50% by weight and more particularly of between 20% and 40%, a content (mol%) of -1,2 units in the butadiene part of between 4% and 85%, a content (mol%) of trans -1,4 units in the butadiene part of between 6% and 80%, a content (mol%) of -1,2 plus -3,4 units in the isoprene part of between 5% and 70% and a content (mol%) of trans -1,4 units in the isoprene part of between 5% and 70% between 10% and 50%, and more generally any butadiene-styrene-isoprene copolymer having a Tg between - 5°C and - 70°C.

[0046] The initial polymers usable in the context of the invention, preferably elastomers, more preferably diene elastomers, can have any microstructure which depends on the polymerization conditions used. These polymers can be, for example, block, random, sequenced, microsequenced, and can be prepared in dispersion, emulsion or solution. They can be coupled and / or star-shaped, for example by means of a silicon or tin atom which links the polymer chains together.

[0047] As seen previously, the initial diene elastomer is modified by grafting a compound of formula (I) also called a modifying agent: in which: A represents an arenediyl ring, optionally substituted by one or more hydrocarbon chains, identical or different, aliphatic, preferably saturated, linear or branched, optionally substituted or interrupted by one or more heteroatoms; E represents a divalent hydrocarbon group optionally comprising one or more heteroatoms; and X denotes a halogen atom, preferably a chlorine atom.

[0048] A represents an arenediyl ring, optionally substituted by one or more hydrocarbon chains, identical or different, aliphatic, preferably saturated, linear or branched, optionally substituted or interrupted by one or more heteroatoms.

[0049] For the purposes of the present invention, the term "arenediyl ring" means a monocyclic or polycyclic aromatic hydrocarbon group derived from an arene in which two hydrogen atoms have been removed. An arenediyl ring is therefore a divalent group.

[0050] For the purposes of the present invention, the term "monocyclic or polycyclic aromatic hydrocarbon group" means one or more aromatic rings whose skeleton is made up of carbon atoms. In other words, there are no heteroatoms in the skeleton of the ring. The arenediyl ring may be monocyclic, i.e. made up of a single ring, or polycyclic, i.e. made up of several condensed aromatic hydrocarbon rings; such condensed rings then have at least two successive carbon atoms in common. These rings may be ortho-condensed or ortho- and peri-condensed.

[0051] Preferably, the arenediyl ring comprises from 6 to 14 carbon atoms.

[0052] The arenediyl ring may be unsubstituted, partially substituted, or fully substituted. An arenediyl ring is partially substituted when one or two or more hydrogen atoms (but not all atoms) are replaced by one or two or more aliphatic, preferably saturated, linear or branched hydrocarbon chains, optionally substituted by one or more heteroatoms. Said chains are also called substituents. If all hydrogen atoms are replaced by said chains, then the arenediyl ring is fully substituted. The substituents of the arenediyl ring may be the same or different from each other.

[0053] Preferably, when the arenediyl ring is substituted by one or more hydrocarbon chains, identical or different, aliphatic, preferably saturated, linear or branched, optionally substituted or interrupted by one or more heteroatoms, this or these chains may be inert with respect to the N-substituted imidazolidinone function and the nitrile oxide.

[0054] For the purposes of the present invention, the term "hydrocarbon chain inert with respect to the N-substituted imidazolidinone function and the nitrile oxide" means a hydrocarbon chain which does not react with said N-substituted imidazolidinone function or with said nitrile oxide. Thus, said hydrocarbon chain inert with respect to said N-substituted imidazolidinone function and said nitrile oxide is preferably an aliphatic hydrocarbon chain which does not have alkenyl or alkynyl functions capable of reacting with said function or said group, i.e. is a saturated, linear or branched aliphatic hydrocarbon chain, optionally substituted or interrupted by one or more heteroatoms, and preferably comprising from 1 to 24 carbon atoms.

[0055] Preferably, the group A is a C6-C14 arenediyl ring optionally substituted by one or more hydrocarbon chains, identical or different, aliphatic, preferably saturated, linear or branched, optionally substituted or interrupted by one or more heteroatoms. More preferably, the group A is a C6-C14 arenediyl ring, optionally substituted by one or more hydrocarbon chains, identical or different, saturated, C1-C24, linear or branched, optionally substituted or interrupted by one or more heteroatoms of nitrogen, sulfur or oxygen.Even more preferably, the group A is a C6-C14 arenediyl ring, optionally substituted by one or more substituents, identical or different, chosen from the group consisting of a C1-C12 alkyl (more preferably C1-C6, even more preferably C1-C4), an OR' group, an -NHR' group, an -SR' group where R' is a C1-C12 alkyl group, more preferably C1-C6, even more preferably C1-C4.

[0056] Preferably, the compound of formula (I) is chosen from the compounds of formula (Ia) and (Ib) in which: a group chosen from R1 to R5 of formula (Ia) and a group chosen from R1 to R7 of formula (Ib) designate the group of formula (II) following: in which E and X are as defined above, the four groups of formula (Ia) chosen from R1 to R5 other than that designating the group of formula (II) and the six groups of formula (Ib) chosen from R1 to R7 other than that designating the group of formula (II), identical or different, represent, independently of each other, a hydrogen atom or an aliphatic hydrocarbon chain, preferably saturated, linear or branched, optionally substituted or interrupted by one or more heteroatoms.

[0057] Preferably, in the compounds of formula (Ia) and (Ib), the four groups of formula (Ia) chosen from R1 to R5 other than that designating the group of formula (II) and the six groups of formula (Ib) chosen from R1 to R7 other than that designating the group of formula (II), identical or different, represent, independently of each other, a hydrogen atom or a saturated, linear or branched, C1-C24 aliphatic hydrocarbon chain, optionally substituted or interrupted by one or more heteroatoms.

[0058] More preferably still, in the compounds of formula (Ia) and (Ib), the four groups of formula (Ia) chosen from R1 to R5 other than that designating the group of formula (II) and the six groups of formula (Ib) chosen from R1 to R7 other than that designating the group of formula (II), identical or different, are chosen from the group formed by a hydrogen atom, a C1-C12 alkyl (more preferably C1-C6, more preferably still C1-C4), an -OR' group, an -NHR' group and an -SR' group where R' is a C1-C12 alkyl, more preferably C1-C6, more preferably still C1-C4.

[0059] According to a preferred embodiment of the invention, in formula (Ia), R2 represents a group of formula (II) as defined above and R1, R3, R4 and R5, identical or different, represent a hydrogen atom or an aliphatic hydrocarbon chain, preferably saturated, linear or branched, C1-C24, optionally substituted or interrupted by one or more heteroatoms. More preferably, R2 represents a group of formula (II) as defined above and R1, R3, R4 and R5, identical or different, are chosen from the group consisting of a hydrogen atom, a C1-C12 alkyl (more preferably C1-C6, even more preferably C1-C4), an -OR' group, an -NHR' group and an -SR' group where R' is a C1-C12 alkyl, more preferably C1-C6, even more preferably C1-C4.

[0060] Even more preferably in this embodiment, R2 represents a group of formula (II) as defined above, R4 represents a hydrogen atom and R1, R3 and R5 represent an aliphatic hydrocarbon chain, preferably saturated, linear or branched, C1-C24, optionally substituted or interrupted by one or more heteroatoms. Even more preferably, R2 represents a group of formula (II) as defined above, R4 represents a hydrogen atom and R1, R3 and R5, identical or different, are chosen from the group consisting of a C1-C12 alkyl (more preferably C1-C6, more preferably still C1-C4), an -OR' group, an -NHR' group and an -SR' group where R' is a C1-C12 alkyl, more preferably C1-C6, more preferably still C1-C4.

[0061] According to another preferred embodiment of the invention, in formula (Ib), R1 represents a group of formula (II) as defined above and R2 to R7, which may be identical or different, represent a hydrogen atom or an aliphatic hydrocarbon chain, preferably saturated, linear or branched, in C1-C24, optionally substituted or interrupted by one or more heteroatoms. More preferably, R1 represents a group of formula (II) as defined above and R2 to R7, which may be identical or different, are chosen from the group consisting of a hydrogen atom, a C1-C12 alkyl (more preferably C1-C6, more preferably still C1-C4), an -OR' group, an -NHR' group and an -SR' group where R' is a C1-C12 alkyl, more preferably C1-C6, more preferably still C1-C4.Even more preferably in this embodiment, R1 represents a group of formula (II) as defined above and R2 to R7, which are identical, represent a hydrogen atom.

[0062] In the compounds of formula (I), (Ia) and (Ib), the group E is a divalent hydrocarbon group which may optionally contain one or more heteroatom(s). For the purposes of the present invention, the term "divalent hydrocarbon group" means a spacer group (or a linking group) forming a bridge between the group A and the N-substituted imidazolidinone group, this spacer group being a saturated or unsaturated, preferably saturated, C1-C24, linear or branched hydrocarbon chain which may optionally contain one or more heteroatom(s) such as, for example, N, O and S. Said hydrocarbon chain may optionally be substituted, provided that the substituents do not react with nitrile oxide and the N-substituted imidazolidinone group as defined above.

[0063] Preferably, in the compounds of formula (I), (Ia) and (Ib), the group E is a hydrocarbon chain, linear or branched, preferably saturated, in C1-C24, more preferably in C1-C10, even more preferably in C1-C6, optionally interrupted by one or more nitrogen, sulfur or oxygen atoms.

[0064] Preferably, in the compounds of formula (I), (Ia) and (Ib), the group E is chosen from the group consisting of -R-, -NH-R-, -OR- and -SR- where R is a linear or branched alkylene, C1-C24, preferably C1-C10, more preferably C1-C6.

[0065] More preferably still, in the compounds of formula (I), (Ia) and (Ib), the group E is chosen from the group consisting of -R- and -OR- where R is a linear or branched alkylene, C1-C24, preferably C1-C10, more preferably C1-C6.

[0066] More preferably still, in the compounds of formula (I), (Ia) and (Ib), the group E is chosen from -CH2-, -CH2-CH2-, -CH2-CH2-CH2-, -CH2-CH2-CH2-CH2-, -O-CH2-, -O-CH2-CH2-, -O-CH2-CH2-CH2- and -O-CH2-CH2-CH2-CH2-.

[0067] According to a preferred embodiment, the compound of formula (I) is the compound of formula (Ib).

[0068] According to this preferred embodiment, the compound of formula (Ib) as defined above is particularly preferred with the group E chosen from the group consisting of -R- and -OR- where R is a linear or branched alkylene, C1-C24, preferably C1-C10, more preferably C1-C6 and with the group X which is a chlorine atom.

[0069] According to this embodiment, more preferably still, the compound of formula (I) is the compound of formula (Ib) with: R1 represents a group of formula (II) in which the group E is chosen from the group consisting of -R- and -OR- where R is a linear or branched alkylene, C1-C24, preferably C1-C10, more preferably C1-C6 and the group X denotes a chlorine atom; and R2 to R7, identical or different, represent a hydrogen atom or an aliphatic hydrocarbon chain, preferably saturated, linear or branched, C1-C24, optionally substituted or interrupted by one or more heteroatoms.

[0070] According to this embodiment, more preferably still, the compound of formula (I) is the compound of formula (Ib) with: R1 represents a group of formula (II) in which the group E is chosen from the group consisting of -R- and -OR- where R is a linear or branched alkylene, C1-C24, preferably C1-C10, more preferably C1-C6 and the group X denotes a chlorine atom; and R2 to R7, identical or different, are chosen from the group consisting of a hydrogen atom, a C1-C12 alkyl (more preferably C1-C6, more preferably still C1-C4), an -OR' group, an -NHR' group and an -SR' group where R' is a C1-C12 alkyl, more preferably C1-C6, more preferably still C1-C4.

[0071] According to this embodiment, more preferably still, the compound of formula (I) is the compound of formula (Ib) with: R1 represents a group of formula (II) in which the group E is chosen from the group consisting of -R- and -OR- where R is a linear or branched alkylene, C1-C24, preferably C1-C10, more preferably C1-C6 and the group X denotes a chlorine atom; and R2 to R7, identical, represent a hydrogen atom.

[0072] According to a particular embodiment, the compound of formula (I) is chosen from the group consisting of the compound of formula (III) and of formula (IV), more preferably is the compound of formula (III)

[0073] The compounds of formula (I), in particular those of formula (Ia), (Ib), (III) and (IV) can be obtained from a synthesis process comprising the following successive steps: (b1) the reaction of a compound of the following formula (IX): in which A is as defined above and Y represents a nucleophilic group, with a compound of the following formula (X): in which E is as defined above, and Z represents a nucleofugal group; in the presence of at least one polar solvent S1, of at least one base, at a temperature T1 ranging from 70 to 150°C, to form a compound of the following formula (XI): (b2) reacting said compound of formula (XI) with an aqueous solution of hydroxylamine at a temperature T2 ranging from 30 to 70°C, to obtain an oxime compound of the following formula (XII): (c) a step of recovering said oxime compound of formula (XII); (d) a step of oxidizing the oxime compound of formula (XII) with an oxidizing agent, in the presence of at least one organic solvent S2, the level of the oxidizing agent being at least 6 molar equivalents relative to the molar quantity of oxime compound of formula (XII).

[0074] For the purposes of this application, the term “polar solvent” means a solvent having a dielectric constant greater than 2.2.

[0075] For the purposes of this application, “nucleofugal group” means a leaving group which carries away its bond doublet.

[0076] For the purposes of the present application, the term “nucleophilic group” means a compound comprising at least one atom carrying a free doublet or a negatively charged atom.

[0077] As explained above, the process for synthesizing the compound of formula (I) comprises in particular the successive steps (b1) and (b2).

[0078] According to a particular embodiment, the two steps (b1) and (b2) are separated by a step of isolation and purification of the compound of formula (XI).

[0079] According to another embodiment, the two steps (b1) and (b2) are carried out according to a one-pot synthesis, that is to say that steps (b1) and (b2) are “one pot” (one-pot synthesis process in two steps), i.e. without isolation of the intermediate compound of formula (XI).

[0080] The process comprises a step (b1) of reacting a compound of formula (IX), as mentioned above, carrying a group Y, with a compound of formula (X), as mentioned above, carrying a group Z.

[0081] Preferably, the group Y is chosen from hydroxyl, thiol and primary or secondary amine functions.

[0082] The Z group may be selected from chlorine, bromine, iodine, mesylate group, tosylate group, acetate group and trifluoromethylsulfonate group.

[0083] Said step (b1) of the process is carried out in the presence of at least one polar solvent S1, and at least one base, at a temperature T1 ranging from 70 to 150°C.

[0084] According to a particular embodiment of the method, the polar solvent S1 is a polar solvent miscible in water, preferably a protic solvent.

[0085] Dimethylformamide (DMF), dimethyl sulfoxide (DMSO), 1,3-dimethyl-2-imidazolidinone (DMI), 1,3-dimethyl-3,4,5,6-tetrahydro-2(1H)-pyrimidinone (DMPU), isopropanol, acetonitrile, ethanol, n-butanol and n-propanol are examples of S1 solvents that can be used in the process.

[0086] Preferably, the protic solvent is alcoholic.

[0087] Advantageously, the compound of formula (IX) represents from 5 to 40% by weight, preferably from 10 to 30% by weight, relative to the weight of the solvent.

[0088] The base may be chosen from alkali metal alcoholates, alkali metal carbonates, alkaline earth metal carbonates, alkali metal hydroxides, alkaline earth metal hydroxides and mixtures thereof.

[0089] Advantageously, it is possible to add: one or more catalysts selected from a silver(I) salt catalyst, a quaternary ammonium phase transfer catalyst, and mixtures thereof; one or more ionic liquids.

[0090] Preferably, the base is chosen from sodium methanolate, potassium carbonate and sodium hydroxide, more preferably potassium carbonate.

[0091] According to a particular embodiment of the process, the molar quantity of base is from 1.5 to 8 molar equivalents, preferably from 2 to 6 molar equivalents, relative to the molar quantity of compound of formula (IX).

[0092] As explained previously, step (b1) of the process is carried out at a temperature T1 ranging from 70 to 150°C.

[0093] Preferably, the temperature T1 is a temperature ranging from 70 to 120°C, more preferably from 80 to 110°C.

[0094] As explained previously, step (b1) of the process is followed by step (b2) of adding to the reaction medium containing the compound of formula (XI) an aqueous solution of hydroxylamine at a temperature T2 ranging from 30 to 70°C.

[0095] Preferably, the addition of the aqueous hydroxylamine solution is carried out when the conversion of the compound of formula (IX) is at least 70% by weight.

[0096] Advantageously, the temperature T2 varies from 40 to 60°C.

[0097] The process also comprises a step (c) of recovery, as mentioned above, of the oxime compound of formula (XII).

[0098] Preferably, the oxime compound of formula (XII) is recovered by precipitation with water, optionally followed by washing with water.

[0099] The method also comprises a step (d) of oxidation of the oxime compound of formula (XII) with an oxidizing agent to give the compound of formula (I), in particular the preferred compounds, in the presence of at least one organic solvent S2; the amount of oxidizing agent is at least 6 molar equivalents, preferably from 6.5 to 15 molar equivalents, relative to the molar amount of oxime compound of formula (XII).

[0100] This amount of oxidizing agent may be added all at once or in several times during step (d), preferably added twice during step (d).

[0101] Preferably, said oxidizing agent is chosen from sodium hypochlorite, N-bromosuccinimide in the presence of a base and N-chlorosuccinimide in the presence of a base, preferably said oxidizing agent is sodium hypochlorite.

[0102] Preferably, the organic solvent S2 is an organic solvent chosen from chlorinated solvents and those of the ester, ether and alcohol type, more preferably chosen from dichloromethane, ethyl acetate, butyl acetate, diethyl ether, isopropanol and ethanol, even more preferably chosen from ethyl acetate and butyl acetate.

[0103] Preferably, the oxime compound of formula (XII) represents from 1 to 30% by weight, preferably from 1 to 20% by weight, relative to the total weight of the assembly comprising said oxime compound of formula (XII), said organic solvent S2 and said oxidizing agent. Preferably, this process comprises, after step (d), a step (e) of recovering the compound of formula (I).

[0104] According to a particular embodiment, the method may comprise a step (a2) of manufacturing the compound of formula (X), prior to step (b1), by reacting a compound of the following formula (XIII): in which: E is as defined previously, with an agent allowing the formation of the nucleofugal group Z.

[0105] Preferably, said agent is thionyl chloride.

[0106] Preferably, step (a2) is carried out in the absence or in the presence of at least one solvent S4, preferably a chlorinated solvent, more preferably dichloromethane.

[0107] Advantageously, step (a2) is immediately followed by a step (a3) ​​of recovery of the compound of formula (X), preferably by purification with toluene, more preferably by crystallization of the compound of formula (X) in toluene.

[0108] The modified diene elastomer is obtained by grafting at least one compound of formula (I), preferably at least one compound of formula (Ib), more preferably at least one compound of formula (III), onto at least one unsaturation of the chain of said initial diene elastomer.

[0109] The grafting of the polymer is carried out by reaction of said initial polymer with the nitrile oxide of the compound of formula (I), preferably of the compound of formula (Ib), more preferably of the compound of formula (III). During this reaction, this group forms a covalent bond with the polymer chain. The grafting of the compound of formula (I), preferably of the compound of formula (Ib), more preferably of the compound of formula (III), is carried out by [3+2] cycloaddition of the nitrile oxide and unsaturation of the initial polymer chain. A mechanism of the [3+2] cycloaddition is illustrated in document WO2012 / 007441.

[0110] According to the invention, the polymer carries along the main polymer chain one or more pendant groups resulting from the grafting reaction of the compound of formula (I), preferably of the compound of formula (Ib), more preferably of the compound of formula (III), as defined above. Advantageously, these pendant groups are distributed along the main polymer chain in a random manner.

[0111] According to a preferred embodiment, the molar rate of grafting of the compound of formula (I), preferably of the compound of formula (Ib), more preferably of the compound of formula (III), is within a range from 0.01% to 5%, preferably from 0.01% to 1%, more preferably from 0.1 to 1%.

[0112] By "molar grafting rate" is meant the number of mol of compound of formula (I), preferably of the compound of formula (Ib), more preferably of the compound of formula (III), grafted onto the polymer per 100 mol of monomer unit constituting the polymer. The molar grafting rate can be determined by conventional polymer analysis methods, such as for example 1< H NMR analysis.

[0113] The grafting of the compound of formula (I), preferably of the compound of formula (Ib), more preferably of the compound of formula (III), onto the initial polymer, can be carried out in bulk, for example in an extruder, in an internal mixer or in an external mixer such as a roller mixer. It can also be carried out in solution, continuously or discontinuously. The polymer thus modified can be separated from its solution by any type of means known to those skilled in the art and in particular by a steam stripping operation.

[0114] In the process described above, the initial polymer is a diene elastomer, as described above.

[0115] In the remainder of the description, for brevity, the diene elastomer, modified by grafting with the compound of formula (I), preferably with the compound of formula (Ib), more preferably with the compound of formula (III), is called polymer P1.

[0116] The invention also relates to a composition comprising at least one modified polymer (polymer P1) as described above and at least one additive.

[0117] The additives that can be used in the composition according to the invention may be plasticizers (such as plasticizing oils and / or plasticizing resins), fillers (reinforcing or non-reinforcing), pigments, protective agents such as anti-ozone waxes, chemical anti-ozonants, antioxidants, anti-fatigue agents, reinforcing resins (as described for example in application WO 02 / 10269), a crosslinking system, for example based on sulfur and other vulcanizing agents, and / or peroxide and / or bismaleimide. Preferably, this additive is a reinforcing filler, more preferably this additive is an inorganic reinforcing filler, even more preferably this additive is a silica.

[0118] Another subject of the present invention is a modified polymer (in the remainder of the description for greater conciseness this polymer is called polymer P2) obtained by grafting at least one compound of formula (I) as described above, preferably at least one compound of formula (Ib), more preferably, at least one compound of formula (III) onto at least one unsaturation of the chain of the initial polymer and at least one compound of formula (V) onto another unsaturation of the chain of the initial polymer in which: A1 represents an arenediyl ring, optionally substituted by one or more hydrocarbon chains, identical or different, aliphatic, preferably saturated, linear or branched, optionally substituted or interrupted by one or more heteroatoms; and E1 represents a divalent hydrocarbon group optionally comprising one or more heteroatoms.

[0119] Polymer P2 is a diene elastomer. The modified polymer P2 of the invention comprises at least one N-substituted imidazolidinone group, i.e. a non-associative nitrogen group, along its chain and at least one unsubstituted imidazolidinone group, i.e. an associative nitrogen group, along its chain. This modified polymer P2 has the advantage of conferring on the compositions containing it, surprisingly, an improvement in the raw rigidity / hysteresis compromise.

[0120] Preferably, the group A1 of the compound of formula (V) is a C6-C14 arenediyl ring optionally substituted by one or more hydrocarbon chains, identical or different, aliphatic, preferably saturated, linear or branched, optionally substituted or interrupted by one or more heteroatoms.More preferably, this group A1 is a C6-C14 arenediyl ring, optionally substituted by one or more identical or different, saturated C1-C24, linear or branched hydrocarbon chains, optionally substituted or interrupted by one or more nitrogen, sulfur or oxygen heteroatoms. Even more preferably, this group A1 is a C6-C14 arenediyl ring, optionally substituted by one or more identical or different substituents, chosen from the group consisting of a C1-C12 alkyl (more preferably C1-C6, even more preferably C1-C4), an -OR' group, an -NHR' group and an -SR' group where R' is a C1-C12 alkyl group, more preferably C1-C6, even more preferably C1-C4.

[0121] Preferably, the compound of formula (V) is chosen from the compounds of formula (Va) and (Vb) in which: a group chosen from R8 to R12 of formula (Va) and a group chosen from R8 to R14 of formula (Vb) designate the group of formula (VI) below in which E1 is as defined above; and the four groups of formula (Va) chosen from R8 to R12 other than that designating the group of formula (VI) and the six groups of formula (Vb) chosen from R8 to R14 other than that designating the group of formula (VI), identical or different, represent, independently of each other, a hydrogen atom or an aliphatic hydrocarbon chain, preferably saturated, linear or branched, optionally substituted or interrupted by one or more heteroatoms.

[0122] Preferably, in the compounds of formula (Va) and (Vb), the four groups of formula (Va) chosen from R1 to R5 other than that designating the group of formula (VI) and the six groups of formula (Vb) chosen from R1 to R7 other than that designating the group of formula (VI), identical or different, represent, independently of each other, a hydrogen atom or a saturated, linear or branched, C1-C24 aliphatic hydrocarbon chain, optionally substituted or interrupted by one or more heteroatoms.

[0123] More preferably still, in the compounds of formula (Va) and (Vb), the four groups of formula (Va) chosen from R1 to R5 other than that designating the group of formula (VI) and the six groups of formula (Vb) chosen from R1 to R7 other than that designating the group of formula (VI), identical or different, are chosen from the group formed by a hydrogen atom, a C1-C12 alkyl (more preferably C1-C6, more preferably still C1-C4), an -OR' group, an -NHR' group and an -SR' group where R' is a C1-C12 alkyl, more preferably C1-C6, more preferably still C1-C4.

[0124] According to a preferred embodiment of the invention, in formula (Va), R9 represents a group of formula (VI) as defined above and R8, R10, R11 and R12, identical or different, represent a hydrogen atom or an aliphatic hydrocarbon chain, preferably saturated, linear or branched, in C1-C24, optionally substituted or interrupted by one or more heteroatoms. More preferably, R9 represents a group of formula (VI) as defined above and R8, R10, R11 and R12, identical or different, are chosen from the group consisting of a hydrogen atom, a C1-C12 alkyl (more preferably C1-C6, even more preferably C1-C4), an -OR' group, an -NHR' group and an -SR' group where R' is a C1-C12 alkyl, more preferably C1-C6, even more preferably C1-C4.

[0125] Even more preferably in this embodiment, in formula (Va), R9 represents a group of formula (VI) as defined above, R11 represents a hydrogen atom and R8, R10 and R12 represent an aliphatic hydrocarbon chain, preferably saturated, linear or branched in C1-C24, optionally substituted or interrupted by one or more heteroatoms. More preferably still, R9 represents a group of formula (VI) as defined above, R11 represents a hydrogen atom and R8, R10 and R12, identical or different, are chosen from the group consisting of a C1-C12 alkyl (more preferably C1-C6, more preferably still C1-C4), an -OR' group, an -NHR' group and an -SR' group where R' is a C1-C12 alkyl, more preferably C1-C6, more preferably still C1-C4.

[0126] According to another preferred embodiment of the invention, in formula (Vb), R8 represents a group of formula (VI) as defined above and R9 to R14, identical or different, represent a hydrogen atom or an aliphatic hydrocarbon chain, preferably saturated, linear or branched, in C1-C24, optionally substituted or interrupted by one or more heteroatoms. More preferably, R8 represents a group of formula (VI) as defined above and R9 to R14, identical or different, are chosen from the group consisting of a hydrogen atom, a C1-C12 alkyl (more preferably C1-C6, more preferably still C1-C4), an -OR' group, an -NHR' group, an -SR' group where R' is a C1-C12 alkyl, more preferably C1-C6, more preferably still C1-C4.Even more preferably in this embodiment, R8 represents a group of formula (VI) as defined above and R9 to R14, which are identical, represent a hydrogen atom.

[0127] In the compounds of formula (V), (Va) and (Vb), the group E1 is a divalent hydrocarbon group which may optionally contain one or more heteroatom(s). For the purposes of the present invention, the term "divalent hydrocarbon group" means a spacer group (or a linking group) forming a bridge between the group A1 and the imidazolidinone group, this spacer group being a saturated or unsaturated, preferably saturated, C1-C24, linear or branched hydrocarbon chain which may optionally contain one or more heteroatom(s) such as, for example, N, O and S. Said hydrocarbon chain may optionally be substituted, provided that the substituents do not react with the nitrile oxide and the imidazolidinone group as defined above.

[0128] Preferably, in the compounds of formula (V), (Va) and (Vb), the group E1 is a hydrocarbon chain, linear or branched, preferably saturated, in C1-C24, more preferably in C1-C10, even more preferably in C1-C6, optionally interrupted by one or more nitrogen, sulfur or oxygen atoms.

[0129] Preferably, in the compounds of formula (V), (Va) and (Vb), the group E1 is chosen from the group consisting of -R-, -NH-R-, -OR- and -SR- where R is a linear or branched alkylene, C1-C24, preferably C1-C10, more preferably C1-C6.

[0130] More preferably still, in the compounds of formula (V), (Va) and (Vb), the group E1 is chosen from the group consisting of -R- and -OR- where R is a linear or branched alkylene, C1-C24, preferably C1-C10, more preferably C1-C6.

[0131] More preferably still, in the compounds of formula (V), (Va) and (Vb), the group E1 is chosen from -CH2-, -CH2-CH2-, -CH2-CH2-CH2-, -CH2-CH2-CH2-CH2-, -O-CH2-, -O-CH2-CH2-, -O-CH2-CH2-CH2- and -O-CH2-CH2-CH2-CH2-.

[0132] According to a preferred embodiment, the compound of formula (V) is the compound of formula (Vb).

[0133] In this preferred embodiment, the compound of formula (Vb) as defined above with the group E1 chosen from the group consisting of -R- and -OR- where R is a linear or branched C1-C24, preferably C1-C10, more preferably C1-C6 alkylene is particularly preferred.

[0134] According to this embodiment, more preferably still, the compound of formula (V) is the compound of formula (Vb) with: R8 represents a group of formula (VI) in which the group E1 is chosen from the group consisting of -R- and -OR- where R is a linear or branched alkylene, C1-C24, preferably C1-C10, more preferably C1-C6; and R9 to R14, identical or different, represent a hydrogen atom or an aliphatic hydrocarbon chain, preferably saturated, linear or branched, C1-C24, optionally substituted or interrupted by one or more heteroatoms.

[0135] According to this embodiment, more preferably still, the compound of formula (V) is the compound of formula (Vb) with: R8 represents a group of formula (VI) in which the group E1 is chosen from the group consisting of -R- and -OR- where R is a linear or branched alkylene, C1-C24, preferably C1-C10, more preferably C1-C6; and R9 to R14, identical or different, are chosen from the group formed by a hydrogen atom, a C1-C12 alkyl (more preferably C1-C6, more preferably still C1-C4), an -OR' group, an -NHR' group, an -SR' group where R' is a C1-C12 alkyl, more preferably C1-C6, more preferably still C1-C4.

[0136] According to this embodiment, more preferably still, the compound of formula (V) is the compound of formula (Vb) with: R8 represents a group of formula (VI) in which the group E1 chosen from the group consisting of -R- and -OR- where R is a linear or branched alkylene, C1-C24, preferably C1-C10, more preferably C1-C6; and R9 to R14, identical, represent a hydrogen atom.

[0137] According to a preferred embodiment, the compound of formula (V) is chosen from the group consisting of the compound of formula (VII) and of formula (VIII), more preferably still by the compound of formula (VII)

[0138] The compound of formula V, in particular, the compounds of formula (Vb) and (VII), can be, for example, synthesized by the method described in WO2019007881A1.

[0139] The polymer P2 is obtained by grafting the initial polymer with the nitrile oxide of the compound of formula (I) as defined above and with the nitrile oxide of the compound of formula (V) as defined above. During this reaction, the nitrile oxides of the compounds of formula (I) and formula (V) each form a covalent bond with an unsaturation of the polymer chain. The grafting of the compounds of formula (I) and (V) is carried out by [3+2] cycloaddition of the nitrile oxides and the unsaturations of the initial polymer chain. A mechanism of the [3+2] cycloaddition can be found in document WO2012 / 007441.

[0140] According to the invention, the polymer P2 carries along the main polymer chain one or more pendant groups resulting from the grafting reaction of the compounds of formula (I) and (V) as defined above. Advantageously, these pendant groups are distributed along the main polymer chain in a random manner.

[0141] According to a preferred embodiment, the polymer P2 carries along the main polymer chain one or more pendant groups resulting from the grafting reaction of the compounds of formula (Ib) and (Vb) as defined above. Advantageously, these pendant groups are distributed along the main polymer chain in a random manner.

[0142] According to a preferred embodiment, the polymer P2 carries along the main polymer chain one or more pendant groups resulting from the grafting reaction: of the compound of formula (Ib) with R1 represents a group of formula (II) in which the group E is chosen from the group consisting of -R- and -OR- where R is an alkylene, linear or branched, in C1-C24, preferably in C1-C10, more preferably in C1-C6, group X which is a chlorine atom; and R2 to R7, identical or different, are chosen from the group consisting of a hydrogen atom, a C1-C12 alkyl (more preferably C1-C6, even more preferably C1-C4), an -OR' group, an -NHR' group and an -SR' group where R' is a C1-C12 alkyl, more preferably C1-C6, even more preferably C1-C4; and of the compound of formula (Vb) with R8 represents a group of formula (VI) in which the group E1 is chosen from the group consisting of -R- and -OR- where R is a linear or branched alkylene, C1-C24, preferably C1-C10, even more preferably C1-C6;and R9 to R14, identical or different, are chosen from the group formed by a hydrogen atom, a C1-C12 alkyl (more preferably C1-C6, even more preferably C1-C4), a -OR' group, a -NHR' group, a -SR' group where R' is a C1-C12 alkyl, more preferably C1-C6, even more preferably C1-C4. ;

[0143] Advantageously, these pendant groups are distributed along the main polymer chain in a random manner.

[0144] According to an even more preferred embodiment, the polymer P2 carries along the main polymer chain one or more pendant groups resulting from the grafting reaction of the compound of formula (III) and the compound of formula (VII) as defined above. Advantageously, these pendant groups are distributed along the main polymer chain in a random manner.

[0145] Whatever the embodiment, for the polymer P2, the molar rate of grafting of the compound of formula (I), preferably of the compound of formula (Ib), more preferably of the compound of formula (III), is within a range from 0.01% to 5%, preferably from 0.01% to 1%, more preferably from 0.1 to 1% and the molar rate of grafting of the compound of formula (V), preferably of the compound of formula (Vb), more preferably of the compound of formula (VII), is within a range from 0.01% to 5%, preferably from 0.01% to 1%, more preferably from 0.1 to 1%.

[0146] The grafting of the compounds of formula (I) and (V), preferably the compounds of formula (Ib) and (Vb), more preferably the compounds of formula (III) and (VII), onto the initial polymer, can be carried out in bulk, for example in an extruder, in an internal mixer or in an external mixer such as a roller mixer. It can also be carried out in solution, continuously or discontinuously. The polymer thus modified can be separated from its solution by any type of means known to those skilled in the art and in particular by a steam stripping operation. The compounds of formula (I) and (V), preferably the compounds of formula (Ib) and (Vb), more preferably the compounds of formula (III) and (VII), can be introduced simultaneously into the internal or external mixer, or simultaneously into the reactor if the grafting is carried out in solution.They can also be introduced in a staggered manner relative to each other, the order being of no importance for the grafting of these compounds onto the initial polymer chain.

[0147] The invention also relates to a composition comprising at least one modified polymer, polymer P2, as described above and at least one additive as described above. Preferably, this additive is a reinforcing filler, more preferably, this additive is a reinforcing inorganic filler, even more preferably this additive is a silica.

[0148] In addition to the objects described above, the invention relates to at least one of the objects described in the following points: 1. Modified polymer obtained by grafting at least one compound of formula (I) onto at least one unsaturation of the chain of an initial polymer in which: A represents an arenediyl ring, optionally substituted by one or more hydrocarbon chains, identical or different, aliphatic, preferably saturated, linear or branched, optionally substituted or interrupted by one or more heteroatoms; E represents a divalent hydrocarbon group optionally comprising one or more heteroatoms; and X denotes a halogen atom, preferably a chlorine atom, the initial polymer being a diene elastomer. 2. Modified polymer according to point 1, in which the initial polymer is chosen from the group consisting of ethylene-propylene-diene monomer copolymers, butyl rubber, natural rubber, synthetic polyisoprenes, polybutadienes, butadiene copolymers, isoprene copolymers and mixtures of these elastomers. 3.Polymer modified according to any one of the preceding points, in which the molar grafting rate of the compound of formula (I) is within a range from 0.01% to 5%, preferably from 0.01% to 1%, more preferably from 0.1% to 1%. 4. Polymer modified according to any one of the preceding points, in which the group A is a C6-C14 arenediyl ring optionally substituted by one or more hydrocarbon chains, identical or different, aliphatic, preferably linear or branched, optionally substituted or interrupted by one or more heteroatoms. 5. Polymer modified according to any one of the preceding points, in which the compound of formula (I) is chosen from the compounds of formula (Ia) and (Ib) in which: . a group chosen from R1 to R5 of formula (Ia) and a group chosen from R1 to R7 of formula (Ib) designate the group of formula (II) following: in which E and X are as defined in point 1, the four groups of formula (Ia) chosen from R1 to R5 other than that designating the group of formula (II) and the six groups of formula (Ib) chosen from R1 to R7 other than that designating the group of formula (II), identical or different, represent independently of each other, a hydrogen atom or an aliphatic hydrocarbon chain, preferably saturated, linear or branched, optionally substituted or interrupted by one or more heteroatoms. 6. Polymer modified according to any one of the preceding points, in which the group E is a hydrocarbon chain, linear or branched, preferably saturated, C1-C24, preferably C1-C10, more preferably C1-C6, optionally interrupted by one or more nitrogen, sulfur or oxygen atoms. 7.Modified polymer according to any one of the preceding points, in which group E is chosen from the group consisting of -R- and -OR- where R is a linear or branched alkylene, C1-C24, preferably C1-C10, more preferably C1-C6. 8. Modified polymer according to any one of points 5 to 7, in which the compound of formula (I) is the compound of formula (Ib). 9. Modified polymer according to any one of the preceding points, in which the compound of formula (I) is the group consisting of the compound of formula (III). 10. Composition comprising at least one polymer modified according to any one of the preceding points and at least one additive, preferably the additive is a filler, more preferably still the additive is a reinforcing filler, even more preferably the additive is an inorganic reinforcing filler, more preferably still the additive is a silica. 11. Tread comprising at least one composition as defined in point 10. 12. Tire comprising at least one composition as defined in point 10. 13. Tire comprising at least one tread as defined in point 11. 14. Polymer modified according to any one of points 1 to 9, characterized in that it is further obtained by grafting at least one compound of formula (V) onto at least one other unsaturation of the chain of said initial polymer in which: A1 represents an arenediyl ring, optionally substituted by one or more hydrocarbon chains, identical or different, aliphatic, preferably saturated, linear or branched, optionally substituted or interrupted by one or more heteroatoms; and E1 represents a divalent hydrocarbon group optionally comprising one or more heteroatoms. 15. Modified polymer according to point 14, in which the molar rate of grafting of the compound of formula (V) is within a range from 0.01% to 5%, preferably from 0.01% to 1%, more preferably from 0.1 to 1%. 16.Modified polymer according to any one of points 14 to 15, in which the group A1 of the compound of formula (V) is a C6-C14 arenediyl ring optionally substituted by one or more hydrocarbon chains, identical or different, aliphatic, preferably saturated, linear or branched, optionally substituted or interrupted by one or more heteroatoms. 17. Modified polymer according to any one of points 14 to 16, in which the compound of formula (V) is chosen from the compounds of formula (Va) and (Vb). in which: a group chosen from R8 to R12 of formula (Va) and a group chosen from R8 to R14 of formula (Vb) designate the group of formula (II) below with E1 as defined in point 14; and the four groups of formula (Va) chosen from R8 to R12 other than that designating the group of formula (VI) and the six groups of formula (Vb) chosen from R8 to R14 other than that designating the group of formula (VI), identical or different, represent, independently of each other, a hydrogen atom or an aliphatic hydrocarbon chain, preferably saturated, linear or branched, optionally substituted or interrupted by one or more heteroatoms. 18. Modified polymer according to any one of points 14 to 17, in which the group E1 of the compound of formula (V) or of formula (VI) is a hydrocarbon chain, linear or branched, preferably saturated, C1-C24, preferably C1-C10, more preferably C1-C6, optionally interrupted by one or more nitrogen, sulfur or oxygen atoms. 19.Modified polymer according to any one of points 14 to 18, in which the group E1 of the compound of formula (V) or of formula (VI) is chosen from the group consisting of -R- and -OR- where R is a linear or branched alkylene, C1-C24, preferably C1-C10, more preferably C1-C6. 20. Modified polymer according to any one of points 14 to 19, in which the compound of formula (V) is the compound of formula (Vb). 21. Modified polymer according to any one of points 14 to 20, in which the compound of formula (V) is the compound of formula (VII). 22. Composition comprising at least one modified polymer as defined in any one of points 14 to 20 and at least one additive, preferably the additive is a filler, more preferably still the additive is a reinforcing filler, even more preferably the additive is an inorganic reinforcing filler, more preferably still the additive is a silica. 23. Tread comprising at least one composition as defined in point 22. 24. Tire comprising at least one composition as defined in point 22. 25. Tire comprising at least one tread as defined in point 23. 26.Blend of modified polymers, comprising at least two polymers chosen from: ▪ a polymer P1 defined according to any one of points 1 to 9, ▪ a polymer P2 defined according to any one of points 14 to 21, ▪ a polymer P3 obtained by grafting at least one compound of formula (V) onto at least one unsaturation of the chain of an initial polymer in which: A1 represents an arenediyl ring, optionally substituted by one or more hydrocarbon chains, identical or different, aliphatic, preferably saturated, linear or branched, optionally substituted or interrupted by one or more heteroatoms; E1 represents a divalent hydrocarbon group optionally comprising one or more heteroatoms; and the initial polymers of the modified polymers P1 and P3 may be identical or different; and on the condition that said blend comprises at least said polymer P1 or said polymer P2. 27.Mixture of modified polymers according to point 26, in which the initial polymers of polymers P1 and P3 are elastomers, preferably diene elastomers, which are identical or different. 28. Mixture of modified polymers according to point 27, in which the diene elastomers are chosen from the group consisting of ethylene-propylene-diene monomer copolymers, butyl rubber, natural rubber, synthetic polyisoprenes, polybutadienes, butadiene copolymers, in particular ethylene and butadiene copolymers, isoprene copolymers and mixtures of these elastomers. 29. Mixture of modified polymers according to any one of points 26 to 28, in which the molar rate of grafting of the compound of formula (V) on the polymer P3 is within a range from 0.01% to 5%, preferably from 0.01% to 1%, more preferably from 0.1% to 1%. 30. Mixture of modified polymers according to any one of points 26 to 29, in which the group A1 of the compound of formula (V) on the polymer P3 is a C6-C14 arenediyl ring optionally substituted by one or more hydrocarbon chains, identical or different, aliphatic, preferably saturated, linear or branched, optionally substituted or interrupted by one or more heteroatoms. 31. Blend of modified polymers according to any one of points 26 to 30, in which the compound of formula (V) on the polymer P3 is chosen from the compounds of formula (Va) and (Vb) in which: a group chosen from R8 to R12 of formula (Va) and a group chosen from R8 to R14 of formula (Vb) designates the group of formula (VI) following with E1 as defined in point 27, and the other groups of formula (Va) chosen from R8 to R12 other than that designating the group of formula (VI) and the six groups of formula (Vb) chosen from R8 to R14 other than that designating the group of formula (VI), identical or different, represent independently of each other, a hydrogen atom or an aliphatic hydrocarbon chain, preferably saturated, linear or branched, optionally substituted or interrupted by one or more heteroatoms. 32. Mixture of modified polymers according to any one of points 26 to 31, in which group E1 of the compound of formula (V) or of formula (VI) of the polymer P3 is a linear or branched, preferably saturated, C1-C24, preferably C1-C10, more preferably C1-C6 hydrocarbon chain, optionally interrupted by one or more nitrogen, sulfur or oxygen atoms. 33.Mixture of modified polymers according to any one of points 26 to 32, in which group E1 of the compound of formula (V) or of formula (VI) of the polymer P3 is chosen from the group consisting of -R- and -OR- where R is a linear or branched alkylene, C1-C24, preferably C1-C10, more preferably C1-C6. 34. Mixture of modified polymers according to any one of points 26 to 33, in which the compound of formula (V) is chosen from the group consisting of the compound of formula (VII) and of formula (VIII), more preferably the compound of formula (VII). 35. Blend of modified polymers according to any one of points 26 to 34, wherein: polymer P1 is a modified polymer, as defined above, obtained by grafting at least one compound of formula (Ia); polymer P2, as defined above, obtained by grafting at least one compound of formula (Ia) and at least one compound of formula (Va); and polymer P3 is a modified polymer, as defined above, obtained by grafting at least one compound of formula (Va). 36. Blend of modified polymers according to any one of points 26 to 34, wherein: polymer P1 is a modified polymer, as defined above, obtained by grafting at least one compound of formula (Ib); the polymer P2, as defined above, obtained by grafting at least one compound of formula (Ib) and at least one compound of formula (Vb); and the polymer P3 is a modified polymer, as defined above, obtained by grafting at least one compound of formula (Vb). 37.Composition comprising at least one mixture of modified polymers as defined in any one of points 26 to 36 and at least one additive, preferably the additive is a filler, more preferably still the additive is a reinforcing filler, even more preferably the additive is an inorganic reinforcing filler, more preferably still the additive is a silica. 38. Tread comprising at least one composition as defined in point 37. 39. Tire comprising at least one composition as defined in point 37. 40. Tire comprising at least one tread as defined in point 38. . EXAMPLES:

[0149] The following examples illustrate the invention; however, the latter cannot be limited to these examples alone. 1 Tests and measurements used 1.1 Determination of the glass transition temperature

[0150] The glass transition temperature Tg of polymers is measured using a differential scanning calorimeter according to ASTM D3418 (2015). 1.2 Measurement of number-average molar masses (Mn), weight-average molar masses (Mw) and polydispersity index for elastomers

[0151] Size exclusion chromatography (SEC) is used. SEC separates macromolecules in solution according to their size through columns filled with a porous gel. The macromolecules are separated according to their hydrodynamic volume, with the largest being eluted first.

[0152] Although not an absolute method, SEC allows us to understand the distribution of molar masses of an elastomer. From commercial standard products, the different number-average (Mn) and weight-average (Mw) molar masses can be determined and the polydispersity index (Ip = Mw / Mn) calculated via a so-called MOORE calibration. Preparation of the elastomer sample to be tested:

[0153] There is no special treatment of the elastomer sample before analysis. It is simply solubilized at a concentration of approximately 1 g / L, in chloroform or in the following mixture: tetrahydrofuran + 1% vol. of diisopropylamine + 1% vol. of triethylamine + 1% vol. of distilled water (% vol. = % volume). Then, the solution is filtered through a 0.45 µm porosity filter before injection. SEC Analysis:

[0154] The apparatus used is a "WATERS alliance" chromatograph. The elution solvent is the following mixture: tetrahydrofuran + 1% vol. diisopropylamine + 1% vol. triethylamine or chloroform depending on the solvent used for dissolving the elastomer. The flow rate is 0.7 mL / min, the system temperature is 35°C and the analysis time is 90 min. A set of four WATERS columns in series is used, with the trade names "STYRAGEL HMW7", "STYRAGEL HMW6E" and two "STYRAGEL HT6E".

[0155] The injected volume of the elastomer sample solution is 100 µL. The detector is a differential refractometer "WATERS 2410" with a wavelength of 810 nm. The chromatographic data processing software is the "WATERS EM POWER" system. The calculated average molar masses are relative to a calibration curve produced from commercial standard polystyrenes "PSS READY CAL-KIT". 1.3 Characterization of molecules

[0156] Structural analysis and determination of molar purities of the synthetic molecules are performed by NMR analysis. Spectra are acquired on an “Avance 3 400 MHz BRUKER” spectrometer equipped with a “broadband BBFO-zgrad 5 mm” probe. The quantitative 1< H NMR experiment uses a single 30° pulse sequence and a 3-second repetition delay between each of the 64 acquisitions. Samples are solubilized in a deuterated solvent, deuterated dimethyl sulfoxide (DMSO) unless otherwise stated. The deuterated solvent is also used for the “lock” signal. For example, calibration is performed on the proton signal of deuterated DMSO at 2.44 ppm compared to a TMS reference at 0 ppm. The 1< H NMR spectrum coupled with 2D HSQC 1< H / 13< C and HMBC 1< H / 13< C experiments allow the structural determination of molecules (see attribution tables). Molar quantifications are carried out from the quantitative 1D 1< H NMR spectrum.

[0157] Mass spectrometry analysis was performed by direct injection using electrospray ionization (DI / ESI) mode. Analyses were performed on a Bruker HCT spectrometer (flow rate 600 µL / min, nebulizer gas pressure 10 psi, nebulizer gas flow rate 4 L / min). 1.4 Characterization of compounds grafted onto diene elastomers

[0158] The determination of the molar ratio of the compounds grafted onto the diene elastomers is carried out by NMR analysis. The spectra are acquired on a “500 MHz BRUKER” spectrometer equipped with a “CryoSonde BBFO-zgrad-5 mm”. The quantitative 1< H NMR experiment uses a single 30° pulse sequence and a 5-second repetition delay between each acquisition. The samples are solubilized in deuterated chloroform (CDCl 3 ) in order to obtain a “lock” signal. 2D NMR experiments have made it possible to verify the nature of the grafted motif thanks to the chemical shifts of the carbon and proton atoms. 1.5 Dynamic Properties

[0159] The dynamic properties G* and tan(δ)max are measured on a viscoanalyzer (Metravib VA4000), according to the ASTM D5992-96 standard. The response of a sample of vulcanized composition (cylindrical specimen 4 mm thick and 400 mm 2< in cross-section) is recorded, subjected to sinusoidal stress in alternating simple shear, at a frequency of 10 Hz, under normal temperature conditions (23°C) according to the ASTM D1349-09 standard. A strain amplitude sweep is carried out from 0.1% to 50% peak-peak (forward cycle) then from 50% to 0.1% peak-peak (return cycle). The results used are the complex dynamic shear modulus G* at 23°C and the dynamic loss factor tan(δ) at 23°C. For the outward journey, the value of the complex dynamic shear modulus G* is recorded at 50% deformation, noted G* 50% outward at 23°C. For the return journey; the maximum value of the dynamic loss factor tan(δ) observed is recorded, noted tan(δ) max at 23°C.

[0160] The results are indicated in base 100; the arbitrary value 100 being assigned to the witness to calculate and then compare tan(δ) max at 23°C and G* 50%go at 23°C of the different samples tested.

[0161] For tan(δ) max at 23°C: the value in base 100 for the test sample is calculated according to the operation: (value of tan(δ) max at 23°C of the test sample / value of tan(δ) max at 23°C of the control) × 100. In this way, a result lower than 100 indicates a decrease in hysteresis which corresponds to an improvement in rolling resistance performance.

[0162] For G* 50% forward at 23°C: the value in base 100 for the sample to be tested is calculated according to the operation: (value of G* 50% forward at 23°C of the sample to be tested / value of G* 50% forward at 23°C of the control) × 100. In this way, a result greater than 100 indicates an improvement in the complex dynamic shear modulus G* 50% forward of deformation at 23°C, which corroborates an improvement in the stiffness of the material. 2 Synthesis of compounds 2.1 - Synthesis of compound A: (2-(2-(3-chloro-2-oxoimidazolidin-1-yl)ethoxy)-1-naphthonitrile oxide

[0163]

[0164] 2-(2-(3-Chloro-2-oxoimidazolidin-1-yl)ethoxy]-1-naphthonitrile oxide is synthesized in six steps, named step a1, step a2, step b1, step b2, step c and step d.

[0165] Step a1 is carried out according to protocol 1, step a2 according to protocol 2, step b1 according to protocol 3. Steps b2 and c are carried out according to protocol 4. Step d is carried out according to protocol 5. Step a1: Preparation of 2-hydroxy-1-naphthaldehyde

[0166] Protocol 1:

[0167] This compound can be obtained from naphthol by a formylation reaction according to the so-called Reimer-Tiemann protocol described in Organic Syntheses, 22, 63-4; 1942 by Russell, Alfred and Lockhart, Luther B. or in Organic Reactions (Hoboken, NJ, United States), 28, 1982 by Wynberg, Hans and Meijer, Egbert W., or according to the procedure described by Casiraghi, Giovanni et al. in Journal of the Chemical Society, Perkin Transactions 1: Organic and Bio-Organic Chemistry (1972-1999), (9), 1862-5, 1980 or by a Vilsmeier reaction described by Jones, Gurnos and Stanforth, Stephen P. in Organic Reactions (Hoboken, NJ, United States), 49, 1997.

[0168] 2-Hydroxy-1-napthaldehyde is commercially available. It can be obtained, for example, from Aldrich (CAS 708-06-5). Step a2: Preparation of 1-(2-chloroethyl)imidazolidin-2-one Protocol 2:

[0169]

[0170] This compound can be obtained according to a protocol described in patent application WO 2012 / 007684. Step b1: Preparation of 2-(2-(2-oxoimidazolidin-1-yl)ethoxy)-1-naphthaldehyde

[0171] Protocol 3:

[0172] A mixture of 2-hydroxy-1-naphthaldehyde (20.0 g; 0.116 mol), potassium carbonate (24.08 g; 0.174 mol), and 1-(2-chloroethyl)imidazolidin-2-one (25.9 g; 0.174 mol) in DMF (20 mL) was heated at 75°C (bath temperature) for 3.0-3.5 hours. Then, a second portion of 1-(2-chloroethyl)imidazolidin-2-one (17.26 g; 0.116 mol) was added, and the reaction mixture was stirred for 9-10 hours at 75°C (bath temperature). After returning to 40-45°C, the reaction medium is poured into a solution of sodium hydroxide (10 g; 0.25 mol) in water (700 mL). The mixture is stirred for 10 to 15 minutes. The precipitate is filtered and washed on the filter with distilled water (3 times 400 mL).

[0173] A gray solid (31.51 g; 95% yield) is obtained.

[0174] The molar purity is greater than 85% (1< H NMR). N° δ 1< H (ppm) δ 13< C (ppm) 1 10,86 191,6 2 / 116,7 3 / 131,5 4 9,19 124,9 5 7,56 130 6 7,37 124,9 7 7,71 128,3 8 / 128,6 9 7,99 137,7 10 7,2 113,1 11 / 162,9 12 4,31 68,7 13 3,63 13,4 14 3,59 16,8 15 3,72 38,3 16 / 162,6 Solvent: CDCl 3 Steps b2 and c: Preparation of 2-(2-(2-oxoimidazolidin-1-yl)ethoxy)-1-naphthaldehyde oxime

[0175]

[0176] The product isolated at the end of protocol 3 is used in the following protocol 4. Protocol 4:

[0177] To a solution of 2-(2-(2-oxoimidazolidin-1-yl)ethoxy)-1-naphthaldehyde (6.3 g; 22.2 mmol) in ethanol (30 mL) at 45°C (bath temperature) is added a solution of hydroxylamine (2.05 g; 31.0 mmol, 50% in water, Aldrich) in ethanol (5 mL). The reaction medium is stirred for 4 hours at 55°C (bath temperature). After returning to 40°C, ethyl acetate (30 mL) is added dropwise over 15 minutes. The precipitate is filtered and washed on the filter with an ethanol / ethyl acetate mixture.

[0178] A white solid (4.00 g; 60% yield) is obtained.

[0179] The molar purity estimated by 1< H NMR is greater than 95%. N° δ 1< H (ppm) δ 13< C (ppm) 1 8,75 147,5 2 / 115,9 3 / 133 4 8,78 127 5 7,46 128,5 6 7,35 125,2 7 7,88 132,8 8 / 130,9 9 7,79 129,4 10 7,36 115,2 11 / 157,1 12 4,28 69,3 13 3,59 44,4 14 3,64 47,6 15 3,40 39,3 16 / 165,3 MeOH solvent Step d: Preparation of 2-(2-(3-chloro-oxoimidazolidin-1-yl)ethoxy)-1-naphthonitrile oxide

[0180] Protocol 5:

[0181] To a suspension of the above 2-(2-(2-oxoimidazolidin-1-yl)ethoxy)-1-naphthaldehyde oxime (7.30 g; 24.4 mmol) in ethyl acetate (230 mL) cooled to 1°C (bath temperature = 0°C) is added dropwise an aqueous solution of NaOCl (74.44 g / L; 98 mL; 4.0 eq. (eq=molar equivalent) over 10 minutes. The reaction medium is stirred for 8.5 hours at 0-2°C (bath temperature = 0°C).

[0182] A second portion of aqueous NaOCl solution (74.44 g / L; 98 mL; 4.0 eq.) is added over 5 minutes. The reaction medium is stirred for 10-11 hours at 0-2°C (bath temperature = 0°C).

[0183] The precipitate is filtered and washed on a filter with water (2 times 25 mL) and then with ethyl acetate (2 times 10 mL).

[0184] A white solid with a melting point of 127.0-127.5 °C is then obtained (6.24 g; 18.7 mmol, yield 77%).

[0185] Compound A, 2-(2-(3-chloro-2-oxoimidazolidin-1-yl)ethoxy)-1-naphthonitrile oxide, is obtained with a molar purity of greater than 92% (1H NMR) and less than 6 mol% of 2-(2-(2-oxoimidazolidin-1-yl)ethoxy)-1-naphthonitrile oxide and 2 mol% of residual solvent impurity. N° δ 1< H (ppm) δ 13< C (ppm) 1 / / 2 / 96,9 3 / 134,0 4 7,93 124,1 5 7,57 129,1 6 7,40 125,3 7 7,78 128,7 8 / 128,7 9 7,90 133,1 10 7,16 112,6 11 / 160,2 12 4,33 68,8 13 3,71 44,8 14 3,75 45,2 15 3,58 52,1 16 / 161,3 Solvent CDCl 3 2.2 - Synthesis of compound B : 2-(2-(2-oxoimidazolidin-1-yl)ethoxy)-1-naphthonitrile oxide

[0186] 2-(2-(2-oxoimidazolidin-1-yl)ethoxy)-1-naphthonitrile oxide is obtained by reproducing the steps of protocols 1 to 4 of paragraph 2.1 to obtain (2-(2-(2-oxoimidazolidin-1-yl)ethoxy)-1-naphthaldehyde oxime, then carrying out protocol 6 described below. Protocol 6:

[0187] To a solution of 2-(2-(2-oxoimidazolidin-1-yl)ethoxy)-1-naphthaldehyde oxime (7.5 g; 25.06 mmol) in dichloromethane (300 mL) cooled to 4°C (bath temperature = 0°C), an aqueous solution of NaOCl (78 g / L; 35 mL; 1.46 eq) is added dropwise for 15 minutes. The reaction medium is stirred for 60 to 70 minutes at a temperature of 4-5°C. The organic phase is separated. The aqueous phase is extracted with dichloromethane (25 mL). The combined organic solutions are washed with water (2 times per 25 mL). The solvent is evaporated under reduced pressure to 40-50 mL. Petroleum ether 40 / 60 (60 mL) is added for crystallization. The precipitate obtained is filtered and washed with 40 / 60 petroleum ether (2 times per 30 mL).

[0188] A white solid (6.46 g; yield 87%) is obtained.

[0189] Product B is obtained with a molar purity estimated by 1< H NMR of greater than 99% and less than 1% residual solvent impurities. N° δ 1< H (ppm) δ 13< C (ppm) 1 / / 2 / 96,7 3 / 134,1 4 7,92 124 5 7,56 128,9 6 7,39 125,2 7 7,77 128,6 8 / 128,5 9 7,89 133 10 7,18 112,7 11 / 160,5 12 4,31 69,4 13 3,64 43,4 14 3,76 47,3 15 3,42 38,5 16 / 162,5 Solvent: CDCl 3 3 Example of modified polymers 3.1 Styrene-butadiene copolymer grafted with 2-(2-(3-chloro-2-oxoimidazolidin-1-yl)ethoxy)-1-naphthonitrile oxide

[0190] 2-(2-(3-chloro-2-oxoimidazolidin-1-yl)ethoxy)-1-naphthonitrile oxide (0.27 g; 0.81 mmol), compound A obtained by the synthesis process described in paragraph 2.1, is incorporated into 20 g of non-functionalized styrene-butadiene copolymer (containing 26.5% by weight of styrene relative to the total weight of the polymer and 25% by weight of 1,2-butadiene unit, relative to the weight of the butadiene part; Mn = 150000 g / mol and Ip = 1.84 measured according to the method described in paragraph 1.2) on a roller tool (external mixer at 23°C). The mixture is homogenized in 15 portfolio passes. This mixing phase is followed by heat treatment at 120°C for 10 minutes under pressure at 10 bars.

[0191] 1< H NMR analysis demonstrated a molar grafting rate of 0.29% with a molar grafting yield of 96%.

[0192] Chemical shift allowing the determination of the grafting rate: 7.6 to 8.2 ppm: 6 H aromatics 4.2 4.3 ppm: 2H CH 2 -O 3.1-3.8 ppm: 6H CH 2 -N 3.2 Polyisoprene grafted with 2-(2-(3-chloro-2-oxoimidazolidin-1-yl)ethoxy)-1-naphthonitrile oxide

[0193] 2-(2-(3-chloro-2-oxoimidazolidin-1-yl)ethoxy)-1-naphthonitrile oxide (0.29 g; 0.88 mmol), compound A obtained by the synthesis process described in paragraph 1.2, is incorporated into 20 g of a synthetic polyisoprene (containing 99.35% by weight of 1,4-cis isoprene unit and 0.65% by weight of 3,4-isoprene unit; Mn=375000 g / mol and Ip=3.6 measured according to the method described in paragraph 1.2) on a roller tool (external mixer at 23°C). The mixture is homogenized in 15 wallet passes. This mixing phase is followed by a heat treatment at 120°C for 10 minutes under pressure at 10 bars.

[0194] 1< H NMR analysis demonstrated a molar grafting rate of 0.2% with a molar grafting yield of 66%.

[0195] Chemical shift allowing the determination of the grafting rate: 7.6 to 8.2 ppm: 6 H aromatics 4.2 4.3 ppm: 2H CH 2 -O 3.1-3.8 ppm: 6H CH 2 -N 4 Example of rubber compositions 4.1 Example 1

[0196] The purpose of this test is to show the improvement in performance in terms of rubber properties of a composition of the invention compared to a conventional non-compliant composition not containing a modified elastomer and to a composition of the prior art comprising a modified elastomer. In particular, these compositions are defined as follows: non-compliant composition C1 is a “conventional” rubber composition used as a tire tread, including in particular an ungrafted synthetic polyisoprene, silica and a polysulfide silane coupling agent; non-compliant composition C2 is identical to composition C1 except that it additionally comprises compound B which is grafted onto the synthetic polyisoprene; composition C3, in accordance with the invention, is a composition identical to composition C1 except that it additionally comprises compound A which is grafted onto the synthetic polyisoprene.

[0197] The rate of the different constituents of these compositions expressed in pce, part by weight per hundred parts by weight of elastomer, are presented in table 1: Table 1 C1 C2 C3 Diene elastomer (1) 100 100 100 Compound B (2) 1,31 Compound A (3) 1,46 Reinforcing charge (4) 60 60 60 Coupling agent (5) 6 6 6 Carbon black (6) 3 3 3 Antioxidant (7) 1,5 1,5 1,5 TMQ (8) 1 1 1 Paraffin 1 1 1 ZnO (9) 2,7 2,7 2,7 Stearic acid (10) 2,5 2,5 2,5 CBS (11) 1,6 1,6 1,6 Sulfur 1,3 1,3 1,3

[0198] Compositions C2 and C3 comprise the same number of mol of grafted compound A or B, namely 0.2 mol%. (1) Polyisoprene containing 99.35% by weight of 1,4-cis isoprene unit and 0.65% by weight of 3,4-isoprene unit; Mn=375000 g / mol and Ip=3.6 measured according to the method described in paragraph 1.2; (2) Compound B: 2-(2-(2-oxoimidazolidin-1-yl)ethoxy)-1-naphthonitrile oxide synthesized according to the method described in paragraph 2.2; (3) Compound A: 2-(2-(3-chloro-2-oxoimidazolidin-1-yl)ethoxy)-1-naphthonitrile oxide synthesized according to the method described in paragraph 2.1; (4) Silica “Zeosil 1165MP” marketed by Solvay; (5) Bis[3-(triethoxysilyl)propyl] tetrasulfide silane (TESPT) marketed by Evonik under the reference “Si69”; (6) Carbon black grade N234 marketed by Cabot Corporation; (7) N-1,3-dimethylbutyl-N-phenyl-para-phenylenediamine marketed by Flexys under the reference “Santoflex 6-PPD”; (8) 2,2,4-trimethyl-1,2-dihydroquinoline marketed by Flexys; (9) Zinc Oxide (industrial grade) marketed by Umicore; (10) Stearin “Pristerene 4031” marketed by Uniquema; (11) N-cyclohexyl-2-benzothiazyl-sulfenamide marketed by Flexys under the reference “Santocure CBS”. .

[0199] Compositions C1 to C3 are prepared as follows: the diene elastomer is introduced into an 85 cm 3 internal “Polylab” mixer, filled to 70% and with an initial tank temperature of approximately 110°C. For compositions concerning compound A or compound B, compound A or compound B is introduced at the same time as the diene elastomer. Then a thermomechanical work of one and a half minutes is carried out at a temperature of 120°C.

[0200] Then, for each of the compositions C1 to C3, the reinforcing filler(s), the agent for coupling the filler with the diene elastomer are introduced, then after one to two minutes of mixing, the various other ingredients with the exception of the vulcanization system. Thermomechanical work (non-productive phase) is then carried out in one step, which lasts a total of approximately 5 minutes, until a maximum drop temperature of 160°C is reached.

[0201] The resulting mixture is recovered, cooled and then the vulcanization system (sulfur and sulfenamide type accelerator) is added to an external mixer (homo-finisher) at 25°C, mixing the whole thing (productive phase) for approximately 5 to 6 minutes.

[0202] The compositions thus obtained are then calendered in the form of plates (thickness of 2 to 3 mm) or thin sheets of rubber for the measurement of their physical or mechanical properties.

[0203] The rubber properties of these compositions are measured after curing at 150°C for 60 minutes. The results obtained are shown in Table 2. Table 2 Compositions C1 C2 C3 Tan(δ) max at 23 C° 100 80 70

[0204] It can be seen from Table 2, as expected, that the non-compliant composition C2 which comprises an elastomer modified with a compound comprising an unsubstituted imidazolidinone function, exhibits a reduction in hysteresis (tan(δ) max at 23°C), compared to the non-compliant composition C1 which does not comprise a modified elastomer.

[0205] Surprisingly, composition C3 according to the invention which comprises an elastomer modified with a compound comprising an N-substituted imidazolidinone function exhibits a significant reduction in hysteresis compared to non-compliant composition C1 as well as a significant reduction in hysteresis compared to non-compliant composition C2 which already exhibited good hysteretic properties compared to non-compliant composition C1.

[0206] The modified elastomer according to the invention therefore makes it possible to reduce the hysteresis of the compositions containing it, and therefore to improve the rolling resistance performance of these compositions. 4.2 Example 2

[0207] The purpose of this test is to show the improvement in the rubber properties of several compositions according to the invention compared to conventional non-compliant compositions not comprising a modified elastomer and to non-compliant prior art compositions comprising a modified elastomer. In particular, these compositions are defined as follows: non-compliant composition C4 is a “conventional” rubber composition used as a tire tread, including in particular an ungrafted styrene-butadiene copolymer (SBR), silica and a silane polysulfide coupling agent; non-compliant composition C5 is identical to composition C4 except that it additionally comprises compound B which is grafted onto the SBR; composition C6, in accordance with the invention, is a composition identical to composition C5 except that it additionally comprises compounds A and B which are grafted onto the SBR; non-compliant composition C7 is identical to composition C4 except that it additionally comprises a synthetic polyisoprene in place of the SBR; non-compliant composition C8 is identical to composition C7 except that it additionally comprises compound B which is grafted onto the synthetic polyisoprene;composition C9, in accordance with the invention, is a composition identical to composition C7 except that it additionally comprises compounds A and B which are grafted onto the synthetic polyisoprene.;

[0208] The rate of the different constituents of the compositions expressed in pce, part by weight per hundred parts by weight of elastomer, are presented in table 3 below: Table 3 C4 C5 C6 C7 C8 C9 Diene elastomer (1) 100 100 100 Diene elastomer (2) 100 100 100 Compound B (3) 1,31 1,31 1,31 1,31 Compound A (4) 0,49 0,49 Reinforcing charge (5) 60 60 60 60 60 60 Coupling agent (6) 6 6 6 6 6 6 Carbon black (7) 3 3 3 3 3 3 Antioxidant (8) 1,5 1,5 1,5 1,5 1,5 1,5 TMQ (9) 1 1 1 1 1 1 Paraffin 1 1 1 1 1 1 ZnO (10) 2,7 2,7 2,7 2,7 2,7 2,7 Stearic acid (11) 2,5 2,5 2,5 2,5 2,5 2,5 CBS (12) 1,6 1,6 1,6 1,6 1,6 1,6 Sulfur 1,3 1,3 1,3 1,3 1,3 1,3 (1) Polyisoprene containing 99.35% by weight of 1,4-cis isoprene unit and 0.65% by weight of 3,4-isoprene unit; Mn=375000 g / mol and Ip=3.6 measured according to the method described in paragraph 1.2; (2) Non-functionalized styrene-butadiene copolymer containing 26.5% by weight of styrene relative to the total weight of the copolymer and 25% by weight of 1,2-butadiene unit relative to the weight of the butadiene part; Mn = 150000 g / mol and Ip=1.84 measured according to the method described in paragraph 1.2; (3) Compound B: 2-(2-(2-oxoimidazolidin-1-yl)ethoxy)-1-naphthonitrile oxide synthesized according to the method described in paragraph 2.2; (4) Compound A: 2-(2-(3-chloro-2-oxoimidazolidin-1-yl)ethoxy)-1-naphthonitrile oxide synthesized according to the method described in paragraph 2.1; (5) Silica “Zeosil 1165MP” marketed by Solvay; (6) Bis[3-(triethoxysilyl)propyl] tetrasulfide silane (TESPT) marketed by Evonik under the reference “Si69”; (7) Carbon black grade N234 marketed by Cabot Corporation; (8) N-1,3-dimethylbutyl-N-phenyl-para-phenylenediamine marketed by Flexys under the reference “Santoflex 6-PPD”; (9) 2,2,4-trimethyl-1,2-dihydroquinoline marketed by Flexys; (10) Zinc Oxide (industrial grade) marketed by Umicore; (11) Stearin “Pristerene 4031” marketed by Uniquema; (12) N-cyclohexyl-2-benzothiazyl-sulfenamide marketed by Flexys under the reference “Santocure CBS”.

[0209] The compositions are prepared as follows: the diene elastomer is introduced into an 85 cm 3 internal “Polylab” mixer, filled to 70% and with an initial tank temperature of approximately 110°C. For the compositions concerning compound B or compounds A and B, compound B or compounds A and B are introduced at the same time as the diene elastomer. Then a thermomechanical work of one and a half minutes is carried out at a temperature of 120°C.

[0210] Then, for each of the compositions C4 to C9, the reinforcing filler(s) are introduced, the filler cutting agent with the diene elastomer, then after one to two minutes of mixing, the various other ingredients with the exception of the vulcanization system. A thermomechanical work (non-productive phase) is then carried out in one step, which lasts a total of approximately 5 minutes, until a maximum drop temperature of 160°C is reached.

[0211] The resulting mixture is recovered, cooled and then the vulcanization system (sulfur and sulfenamide type accelerator) is added to an external mixer (homo-finisher) at 25°C, mixing the whole thing (productive phase) for approximately 5 to 6 minutes.

[0212] The compositions thus obtained are then calendered in the form of plates (thickness of 2 to 3 mm) or thin sheets of rubber for the measurement of their physical or mechanical properties. The rubber properties of these compositions are measured after curing at 150°C for 60 min. The results obtained are shown in Table 4. Table 4 C4 C5 C6 C7 C8 C9 G * 50% go to 23°C 100 100 99 100 100 93 Tan (δ) max at 23 C° 100 81 76 100 80 65

[0213] It can be seen, in view of Table 4, as expected, that the non-compliant compositions C5 and C8 which comprise an elastomer grafted with a compound comprising unsubstituted imidazolidinone functions, exhibit a reduction in hysteresis at iso-rigidity (G * 50% going to 23°C) compared to the non-compliant compositions C4 and C7 respectively which do not comprise a modified elastomer.

[0214] Surprisingly, composition C6 according to the invention, which comprises an elastomer modified with a compound bearing N-substituted imidazolidinone functions and a compound bearing unsubstituted imidazolidinone functions, exhibits a significant reduction in hysteresis compared to non-compliant composition C5, which already exhibited reduced hysteresis compared to non-compliant composition C4. This reduction in hysteresis occurs without a reduction in the cured stiffness properties, which is surprising. Indeed, those skilled in the art know that hysteresis and cured stiffness properties are two antagonistic properties of rubber compositions. It is known that an improvement in the raw stiffness properties leads to a deterioration in hysteresis and vice versa. However, a significant improvement in the cured stiffness / hysteresis compromise of composition C6 according to the invention is observed here, compared to non-compliant compositions C4 and C5.This same result is obtained with composition C9 in accordance with the invention compared to non-compliant compositions C7 and C8; even if a reduction in raw rigidity is observed for composition C9 according to the invention compared to non-compliant composition C8. This reduction in raw rigidity remains very low given the significant reduction in hysteresis of composition C9 according to the invention.

Claims

1. Modified polymer obtained by grafting at least one compound of formula (I) to at least one unsaturation of the chain of an initial polymer: in which: • A represents an arenediyl ring optionally substituted by one or more identical or different, preferably saturated, linear or branched, aliphatic hydrocarbon chains, which are optionally substituted or interrupted by one or more heteroatoms; • E represents a divalent hydrocarbon group optionally comprising one or more heteroatoms; and • X denotes a halogen atom, preferably a chlorine atom, the initial polymer is a diene elastomer.

2. Modified polymer according to Claim 1, in which the initial polymer is selected from the group consisting of ethylene / propylene / diene monomer copolymers, butyl rubber, natural rubber, synthetic polyisoprenes, polybutadienes, butadiene copolymers, isoprene copolymers and the mixtures of these elastomers.

3. Modified polymer according to any one of the preceding claims, in which the group A is a C6-C14 arenediyl ring optionally substituted by one or more identical or different, preferably saturated, linear or branched aliphatic hydrocarbon chains, which are optionally substituted or interrupted by one or more heteroatoms.

4. Modified polymer according to any one of Claims 1 to 3, in which the compound of formula (I) is chosen from the compounds of formula (Ia) and (Ib): in which: • a group chosen from R1 to R5 of the formula (Ia) and a group chosen from R1 to R7 of the formula (Ib) denote the group of following formula (II): in which E and X are as defined in Claim 1; and • the four groups of the formula (Ia) chosen from R1 to R5 other than that denoting the group of formula (II) and the six groups of the formula (Ib) chosen from R1 to R7 other than that denoting the group of formula (II), which are identical or different, represent, independently of one another, a hydrogen atom or a preferably saturated, linear or branched aliphatic hydrocarbon chain optionally substituted or interrupted by one or more heteroatoms.

5. Modified polymer according to any one of the preceding claims, in which the group E is a preferably saturated, linear or branched C1-C24, preferably C1-C10, more preferentially C1-C6, hydrocarbon chain optionally interrupted by one or more nitrogen, sulfur or oxygen atoms.

6. Modified polymer according to either one of Claims 4 and 5, in which the compound of formula (I) is the compound of formula (Ib).

7. Modified polymer according to any one of the preceding claims, in which the compound of formula (I) is the compound of following formula (III):

8. Modified polymer according to any one of the preceding claims, characterized in that it is additionally obtained by grafting at least one compound of formula (V) to at least one other unsaturation of the chain of said initial polymer: in which: • A1 represents an arenediyl ring optionally substituted by one or more identical or different, preferably saturated, linear or branched aliphatic hydrocarbon chains, which are optionally substituted or interrupted by one or more heteroatoms; and • E1 represents a divalent hydrocarbon group optionally comprising one or more heteroatoms.

9. Modified polymer according to Claim 8, in which the group A1 of the compound of formula (V) is a C6-C14 arenediyl ring optionally substituted by one or more identical or different, preferably, linear or branched aliphatic hydrocarbon chains, which are optionally substituted or interrupted by one or more heteroatoms.

10. Modified polymer according to either one of Claims 8 and 9, in which the compound of formula (V) is chosen from the compounds of formula (Va) and (Vb): in which: • a group chosen from R8 to R12 of the formula (Va) and a group chosen from R8 to R14 of the formula (Vb) denote the group of following formula (VI): in which E1 as defined in Claim 8; and • the four groups of the formula (Va) chosen from R8 to R12 other than that denoting the group of formula (VI) and the six groups of the formula (Vb) chosen from R8 to R14 other than that denoting the group of formula (VI), which are identical or different, represent, independently of one another, a hydrogen atom or a preferably saturated, linear or branched aliphatic hydrocarbon chain optionally substituted or interrupted by one or more heteroatoms.

11. Modified polymer according to any one of Claims 8 to 10, in which the group E1 of the compound of formula (V) is a preferably saturated, linear or branched C1-C24, preferably C1-C10, more preferentially C1-C6, hydrocarbon chain optionally interrupted by one or more nitrogen, sulfur or oxygen atoms.

12. Modified polymer according to either one of Claims 10 and 11, in which the compound of formula (V) is the compound of formula (Vb).

13. Modified polymer according to any one of Claims 8 to 12, in which the compound of formula (V) is the compound of following formula (VII):

14. Composition comprising at least one modified dienic elastomer as defined in any one of Claims 1 to 13 and at least one additive.