1,3-dipolar compound bearing a monoalkoxysilane group and process for the synthesis thereof

Abstract

The invention relates to a compound of formula (I) and to the process for the preparation thereof (I) in which: - T is selected from the group consisting of CN+-O-, CH=NOH and CHO; - A represents a C6-C14 arenediyl ring, optionally substituted by one or more hydrocarbon chains, identical or different, aliphatic, preferably saturated, linear or branched; - E represents a C2-C12 divalent hydrocarbon group optionally comprising one or more heteroatoms; and - Ra, Rb, Rc, identical or different, represent a C1-C6 alkyl.

Description

[0001] 1,3-DIPOLAR COMPOUND CARRYING A MONOALCOXYSILANE GROUP AND ITS SYNTHESIS PROCESS

[0002] FIELD OF INVENTION

[0003] The field of the present invention is that of modifying agents for functionalizing unsaturated polymers, that is, polymers bearing unsaturated carbon-carbon bonds in their chains. More specifically, these modifying agents are 1,3-dipolar compounds. The invention also relates to a method for synthesizing these compounds and their synthetic intermediates.

[0004] STATE OF THE ART

[0005] Elastomeric compositions intended for tire manufacturing include unsaturated polymers, particularly elastomers, and reinforcing fillers that impart good reinforcing properties to the elastomeric compositions containing them. Furthermore, the reinforcing fillers influence the hysteresis properties of the elastomeric compositions.

[0006] Ideally, a tire tread should meet a large number of technical requirements, including low hysteresis, while offering the tire very good road handling.

[0007] This level of road behavior can be achieved by using, in the tread, a judiciously chosen elastomeric composition due to its rather high curing rigidity.

[0008] To increase the curing stiffness of an elastomeric composition, it is known, for example, to increase the rate of reinforcing fillers or to reduce the rate of plasticizers in the elastomeric composition or to introduce styrene and butadiene copolymers with a high styrene content.

[0009] However, some of these solutions generally have the drawback of increasing the hysteresis of the elastomeric composition. Conversely, tire manufacturers need elastomeric compositions with low hysteresis to limit vehicle rolling resistance and fuel consumption. Therefore, improving the stiffness properties of the elastomeric composition must not come at the expense of its hysteresis properties.

[0010] It is also known that increased stiffness results in a decrease in the tensile strength properties of elastomeric compounds. If tensile strength properties decrease, the tire will be less resistant to physical stresses, thus exhibiting reduced durability and ultimately a shorter lifespan. Furthermore, given the depletion of raw materials and fossil fuels, it is becoming increasingly important for manufacturers to offer tires with a certain longevity, and therefore good durability. Consequently, it is a constant objective for designers of elastomeric compounds to ensure that the improvement of certain properties does not come at the expense of others, in particular that a reinforced elastomeric compound with high stiffness also exhibits good tensile strength properties and low hysteresis.

[0011] It is known that, generally speaking, to obtain the optimal reinforcing properties conferred by a reinforcing filler, the latter must be present in the elastomeric matrix in a final form that is both as finely divided as possible and as homogeneously distributed as possible. However, such conditions can only be achieved if the reinforcing filler has a very good ability, firstly, to incorporate into the elastomeric matrix during mixing with the elastomer and to deagglomerate, and secondly, to disperse homogeneously within this matrix.

[0012] Carbon black is known to possess such properties, which is generally not the case for inorganic reinforcing fillers like silica. Indeed, due to mutual affinities, inorganic reinforcing filler particles tend to agglomerate within the elastomeric matrix. These interactions limit the dispersion of the inorganic reinforcing filler and thus restrict its reinforcing properties to a level significantly lower than that which could theoretically be achieved if all the bonds (reinforcing fillers / elastomers) that could be formed during the mixing process had actually been established.

[0013] Many solutions have already been tested to achieve good dispersion of the reinforcing inorganic filler in an elastomeric composition and to obtain elastomeric compositions exhibiting a decrease in hysteresis.

[0014] In particular, it is common practice to use polysulfide silane compounds, known as coupling agents for the inorganic reinforcing filler to the elastomer, to improve the dispersion of this reinforcing inorganic filler. However, these coupling agents are manufactured from fossil-based raw materials and are expensive to produce. Given the environmental impact of using these raw materials, it is becoming a major challenge for tire manufacturers to use as few such coupling agents as possible without diminishing the properties of the elastomeric compositions and / or altering the dispersion of the inorganic reinforcing filler within the composition. Furthermore, it is always advantageous for a manufacturer to reduce the production costs of these compositions.

[0015] In order to improve the dispersion of the reinforcing filler, particularly the inorganic reinforcing filler, it is also known to modify the structure of polymers, particularly elastomers, by post-polymerization grafting using modifying or functionalizing agents.

[0016] For example, document W02020 / 094993 describes a grafting agent that is a 1,3-dipolar compound containing an imidazole functional group. This nitrile oxide, 2,4,6-trimethyl-3((2-methyl-1H-imidazol-lyl)methyl)benzene, when grafted to the ethylene-butadiene copolymer elastomer, imparts good properties to compositions reinforced with an inorganic reinforcing filler, as demonstrated by strain measurements. However, the compositions in this document contain a coupling agent for the inorganic reinforcing filler to the elastomer.

[0017] There is, therefore, always a constant need for new elastomer grafting agents that allow access to elastomeric compositions with a good compromise of properties such as stiffness, hysteresis and tensile strength, while maintaining good dispersion of the inorganic reinforcing filler in these compositions.

[0018] DESCRIPTION OF THE INVENTION

[0019] The applicant has thus developed new nitrile oxide compounds comprising a monoalkoxy silane function, which make it possible to meet the needs mentioned above.

[0020] Thus, a first object of the present invention relates, therefore, to a compound of formula (I)

[0021] (I) in which:

[0022] T is chosen from the group formed by CN + -0', CH=NOH and CHO;

[0023] A represents an arenediyl ring in CÔ-CU, possibly substituted by one or more hydrocarbon chains, identical or different, aliphatic, preferably saturated, linear or branched;

[0024] E represents a divalent hydrocarbon group in the C2-C12 range, possibly comprising one or more heteroatoms; and

[0025] Ra, Rb, Rc, whether identical or different, represent an alkyl in C1-CO.

[0026] Advantageously, a preferred compound of formula (I) is a compound of formula (la) in which: A represents a CÔ-CU arenediyl ring, possibly substituted by one or more identical or different, aliphatic hydrocarbon chains, preferably saturated, linear or branched;

[0027] E represents a divalent hydrocarbon group in the C2-C12 range, possibly comprising one or more heteroatoms; and

[0028] Ra, Rb, Rc, whether identical or different, represent an alkyl in C1-CO.

[0029] Advantageously, a preferred compound of formula (I) is a compound of formula (Ib)

[0030] (Ib) in which:

[0031] A represents an arenediyl ring in CÔ-CU, possibly substituted by one or more hydrocarbon chains, identical or different, aliphatic, preferably saturated, linear or branched;

[0032] E represents a divalent hydrocarbon group in the C2-C12 range, possibly comprising one or more heteroatoms; and

[0033] Ra, Rb, Rc, whether identical or different, represent an alkyl in C1-CO.

[0034] Advantageously, a preferred compound of formula (I) is a compound of formula (the)

[0035] (Ic) in which:

[0036] A represents an arenediyl ring in CÔ-CU, possibly substituted by one or more hydrocarbon chains, identical or different, aliphatic, preferably saturated, linear or branched;

[0037] E represents a divalent hydrocarbon group in the C2-C12 range, possibly comprising one or more heteroatoms; and

[0038] Ra, Rb, and Rc, whether identical or different, represent a C1-CO alkyl group. Surprisingly, the compounds described above allow for the creation of elastomeric compositions exhibiting a good compromise between stiffness, hysteresis, and tensile strength, while maintaining good dispersion of the inorganic reinforcing filler. Also surprisingly, they allow for the creation of compositions using little to no polysulfide-silane coupling agents. Consequently, the manufacturing cost of these elastomeric compositions is significantly lower.

[0039] Another object of the present invention is a composition based on at least one additive and at least one compound of formula (la) as defined above.

[0040] Another object of the present invention is a process for preparing a compound of formula (la), said process comprising at least one reaction of a compound of formula (Ib) with a halogenating agent in the presence of at least one organic solvent SL1 according to the following reaction scheme: with :

[0041] A represents an arenediyl ring in CÔ-CU, possibly substituted by one or more hydrocarbon chains, identical or different, aliphatic, preferably saturated, linear or branched;

[0042] E represents a divalent hydrocarbon group in the C2-C12 range, possibly comprising one or more heteroatoms; and

[0043] Ra, Rb, Rc, whether identical or different, represent an alkyl in C1-CO.

[0044] DETAILED DESCRIPTION OF THE INVENTION

[0045] As mentioned above, a first object of the present invention relates to a compound of formula (I)

[0046] (I) in which:

[0047] T is chosen from the group formed by CN + -O", CH=NOH and CHO;

[0048] A represents an arenediyl ring in CÔ-CU, possibly substituted by one or more hydrocarbon chains, identical or different, aliphatic, preferably saturated, linear or branched;

[0049] E represents a divalent hydrocarbon group in the C2-C12 range, possibly comprising one or more heteroatoms; and

[0050] Ra, Rb, Rc, whether identical or different, represent an alkyl in C1-CO.

[0051] In this document, unless expressly stated otherwise, all percentages (%) shown are percentages (%) by mass.

[0052] 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 (that is, bounds a and b excluded) while any interval of values ​​designated by the expression "from a to b" means the domain of values ​​going from a to b (that is, including the strict bounds a and b).

[0053] The compounds mentioned in the description can be of fossil origin or bio-based. In the latter case, they may be partially or entirely derived from biomass or obtained from renewable raw materials derived from biomass. Obviously, the compounds mentioned can also come from the recycling of previously used materials; that is, they may be partially or entirely produced through a recycling process, or obtained from raw materials themselves derived from a recycling process. This includes, in particular, polymers, plasticizers, fillers, etc.

[0054] The expression "composition based on" means a composition comprising the mixture and / or the in situ reaction product of the different constituents used, some of these constituents being able to react and / or being intended to react with each other, at least partially, during the different phases of manufacturing the composition; the composition can thus be in a totally or partially crosslinked state or in a non-crosslinked state.

[0055] The expression "part by weight per hundred parts by weight of elastomer" (or pce) is to be understood in the context of the present invention as the part, by mass per hundred parts by mass of elastomer.

[0056] The term 1,3-dipole compound is understood according to the definition given by IUP AC. By definition, a 1,3-dipole compound includes a dipole. When T is CN +-O", the dipole is a nitrile oxide. For the purposes of this invention, "hydrocarbon chain" means a chain comprising one or more carbon atoms and one or more hydrogen atoms.

[0057] The expression "Ci-Cj alkyl" refers to a linear, branched or cyclic hydrocarbon group comprising i to j carbon atoms; i and j being integers.

[0058] The expression "Ci-Cj aryl" refers to an aromatic group containing i to j carbon atoms; i and j being integers.

[0059] An "alkanediyl" is a hydrocarbon group derived from an alkane in which two hydrogen atoms have been removed. An alkanediyl is therefore a divalent group.

[0060] The invention and its advantages will be readily understood in light of the description and implementation examples that follow.

[0061] In the compound of formula (I), the group T is chosen from the group consisting of CN + -O" ; CH=NOH and CHO, also represented as follows with the symbol (*) representing attachment to A.

[0062] According to formula (I), the compound according to the invention comprises group A which represents a CÔ-CU arenediyl ring, optionally substituted by one or more identical or different aliphatic hydrocarbon chains, preferably saturated, linear or branched.

[0063] For the purposes of this invention, an "arendiyl ring" is defined as a monocyclic or polycyclic aromatic hydrocarbon group derived from an arene in which two hydrogen atoms have been removed. An arendiyl ring is therefore a divalent group.

[0064] A monocyclic or polycyclic aromatic hydrocarbon group is defined as one or more aromatic rings whose backbone is composed of carbon atoms. In other words, there are no heteroatoms in the ring's backbone. The arenediyl ring can be monocyclic, meaning it consists of a single ring, or polycyclic, meaning it consists of several condensed aromatic hydrocarbon rings; such condensed rings then share at least two successive carbon atoms. These rings can be orthocondensed or ortho- and pericondensed. The arenediyl ring comprises from 6 to 14 carbon atoms.

[0065] The arenediyl ring can be unsubstituted, partially substituted, or totally substituted. An arenediyl ring is partially substituted when one, two, or more hydrogen atoms (but not all) are replaced by one, two, or more aliphatic hydrocarbon chains, preferably saturated, linear or branched. These chains are also called substituents. If all the hydrogen atoms are replaced by these chains, then the arenediyl ring is totally substituted. The substituents of the arenediyl ring can be identical or different from one another.

[0066] Preferably, when the arenediyl ring is substituted by one or more hydrocarbon chain(s), identical or different, independent of each other, this or these chain(s) are inert with respect to the substituted silicon atom and the chemical group represented by the symbol T (called for brevity group T in the rest of the document).

[0067] For the purposes of this invention, "inert hydrocarbon chain(s) with respect to the substituted silicon atom and the T group" means a hydrocarbon chain that does not react with said substituted silicon atom or with said T group. Thus, said inert hydrocarbon chain with respect to said substituted silicon atom and said T group is, for example, a hydrocarbon chain that does not have alkenyl or alkynyl functions capable of reacting with said substituted silicon atom or said T group. Preferably, these hydrocarbon chains are aliphatic, saturated, linear or branched, and can comprise from 1 to 24 carbon atoms.

[0068] Preferably, A represents a CÔ-CU arendiyl ring, optionally substituted by one or more identical or different hydrocarbon chain(s), saturated at C1-C24. More preferably still, group A is a CÔ-CU arendiyl ring, optionally substituted by one or more substituents, identical or different, the substituents being alkyls at C1-C12, preferably at CI-CÔ, more preferably at C1-C4.

[0069] Preferably, the compound of formula (I) according to the invention is chosen from the compounds of formula (II) and the compounds of formula (III) in which: (i) a grouping chosen from Ri to R5 of formula (II) and a grouping chosen from Ri to R7 of formula (III) denote the following group of formula (IV): in which T, E, Ra, Rb, Rc are as defined above and below and the symbol (*) represents the attachment of group (IV) to the rest of molecule (II) or (III);

[0070] (ii) the four groups of formula (II) chosen from RI to R5 other than that designating the group of formula (IV) and the six groups of formula (III) chosen from RI to R7 other than that designating the group of formula (IV), identical or different, independently represent a hydrogen atom or an aliphatic hydrocarbon chain, preferably saturated, linear or branched in C1-C24, and preferably independently represent a hydrogen atom or an alkyl in C1-C12.

[0071] Preferably, in compounds of formula (I), (la), (Ib), (le), (II), and (III), Ra, Rb, Rc, identical or different, are a C1-C4 alkyl, preferably a C1-C4 alkyl.

[0072] Preferably, in compounds of formula (I), (la), (Ib), (le), (II) and (III), Ra and Rb are identical and are a C1-C4 alkyl, preferably the methyl, and Rc is the ethyl.

[0073] Preferably, in compounds of formula (I), (la), (Ib), (le), (II) and (III), Ra, Rb, Rc, whether identical or different, are methyl or ethyl.

[0074] According to a preferred embodiment of the invention, in the compounds of formula (I), (la), (Ib) (le), (II) and (III), Ra and Rb are methyl and Rc is ethyl.

[0075] Preferably, in compounds of formulas (II) and (III), the four groups of formula (II) chosen from Ri to R5 other than the one designating the group of formula (IV) and the six groups of formula (III) chosen from Ri to R7 other than the one designating the group of formula (IV), whether identical or different, independently represent a hydrogen atom or a saturated, linear or branched, aliphatic hydrocarbon chain of Cl-C 24 .

[0076] Even more preferably, in the compounds of formulas (II) and (III), the four groups of formula (II) chosen from Ri to R5 other than that designating the group of formula (IV) and the six groups of formula (III) chosen from Ri to R7 other than that designating the group of formula (IV), identical or different, are chosen from the group consisting of the hydrogen atom, the alkyls in C1-C12, preferably in C1-C2, even more preferably in C1-C4.

[0077] Even more preferably, in the compounds of formulas (II) and (III), the four groups of formula (II) chosen from Ri to R5 other than that designating the group of formula (IV) and the six groups of formula (III) chosen from Ri to R7 other than that designating the group of formula (IV), identical or different, represent independently of each other, a hydrogen atom or a methyl.

[0078] According to a preferred embodiment of the invention, in formula (II), R2 represents a group of formula (IV) and Ri, R3, R4 and R5, identical or different, represent a hydrogen atom or an aliphatic hydrocarbon chain, preferably saturated, linear or branched, in C1-C24. More preferably, R2 represents a group of formula (IV) and Ri, R3, R4 and R5, identical or different, are chosen from the group consisting of a hydrogen atom and an alkyl in C1-C12, more preferably in C1-C24, more preferably in C1-C4.

[0079] More preferably in this embodiment, R2 represents a group of formula (IV), R4 represents a hydrogen atom, and Ri, R3, and R5 represent an aliphatic hydrocarbon chain, preferably saturated, linear or branched, in C1-C24. More preferably still, R2 represents a group of formula (IV), R4 represents a hydrogen atom, and Ri, R3, and R5, identical or different, represent an alkyl group in C1-C12, more preferably in C1-C2, more preferably in C1-C4.

[0080] According to another preferred embodiment of the invention, in formula (III), Ri represents a group of formula (IV) and R2 to R7, identical or different, represent a hydrogen atom or an aliphatic hydrocarbon chain, preferably saturated, linear or branched, in the C1-C24 configuration. More preferably, Ri represents a group of formula (IV) and R2 to R7, identical or different, are selected from the group consisting of a hydrogen atom and an alkyl group in the C1-C12 configuration, more preferably in the C1-C2 configuration, and more preferably in the C1-C4 configuration. Even more preferably in this embodiment, Ri represents a group of formula (IV) and R2 to R7, identical, represent a hydrogen atom.

[0081] In compounds of formula (I), (la), (Ib), (le), (II) and (III), E represents a C2-C12 hydrocarbon divalent group that may optionally contain one or more heteroatoms. For the purposes of this invention, "hydrocarbon divalent group" means a spacer group (or bonding group) forming a bridge between the oxygen atom attached to A and the silicon atom substituted by Ra, Rb, -ORc, with Ra, Rb and Rc as defined above; this spacer group E comprising from 2 to 12 carbon atoms. This spacer group can be a C2-C12 hydrocarbon chain, preferably saturated, linear or branched, possibly containing 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 T group and the substituted silicon atom as defined above.

[0082] Preferably, in compounds of formula (I), (la), (Ib), (le), (II) and (III), E represents a divalent hydrocarbon group in C2-C10, preferably in C2-C9, more preferably in C2-C7, more preferably still in C2-C5, possibly containing one or more heteroatom(s) such as, for example, N, O and S.

[0083] More preferably, in compounds of formula (I), (la), (Ib), (le), (II) and (III), E represents a C2-C10 alkanediyl, preferably a C2-C9 alkanediyl, more preferably a C2-C7 alkanediyl, and even more preferably a C2-C5 alkanediyl.

[0084] Among compounds with formula (I), compounds with formula (la) are particularly preferred

[0085] (the) with:

[0086] A represents an arenediyl ring in CÔ-CU, possibly substituted by one or more hydrocarbon chains, identical or different, aliphatic, preferably saturated, linear or branched;

[0087] E represents a divalent hydrocarbon group in the C2-C12 range, possibly comprising one or more heteroatoms; and

[0088] Ra, Rb, Rc, whether identical or different, represent an alkyl in C1-CO.

[0089] Preferably, in formula (la), A represents a CÔ-CU arenediyl ring, optionally substituted by one or more identical or different hydrocarbon chain(s), saturated at C1-C24. More preferably still, group A is a CÔ-CU arenediyl ring, optionally substituted by one or more substituents, identical or different, the substituents being alkyls at C1-C12, preferably at CI-CÔ, more preferably at C1-C4.

[0090] Preferably, the compound with formula (la) is chosen from the compounds with formulas (lia) and (Ilia). in which (i) a grouping chosen from Ri to R5 of formula (lia) and a grouping chosen from Ri to R7 of formula (Ilia) denote the following group of formula (IV):

[0091] (IV) in which E, Ra, Rb, Rc are as defined previously and the symbol (*) represents the attachment to (lia) or to (Ilia);

[0092] (ii) the four groups of formula (lia) chosen from Ri to R5 other than that designating the group of formula (IV) and the six groups of formula (Ilia) chosen from Ri to R7 other than that designating the group of formula (IV), identical or different, independently represent a hydrogen atom or an aliphatic hydrocarbon chain, preferably saturated, linear or branched in C1-C24, and preferably independently represent a hydrogen atom or an alkyl in C1-C12.

[0093] In compounds of formula (lia) and (Illa), E represents a divalent C2-C12 hydrocarbon group that may optionally contain one or more heteroatoms. Preferably, this spacer group may be a C2-C12 hydrocarbon chain, preferably saturated, linear or branched, that may optionally contain one or more heteroatoms such as, for example, N, O, and S. This hydrocarbon chain may optionally be substituted, provided that the substituents do not react with the nitrile oxide group and the substituted silicon atom as defined above.

[0094] Preferably, in compounds of formula (lia) and (Illa), E represents a divalent hydrocarbon group in C2-C10, preferably in C2-C9, more preferably in C2-C7, more preferably still in C2-C5, possibly containing one or more heteroatom(s) such as, for example, N, O and S.

[0095] More preferably, in the compounds of formula (lia) and (Illa), E represents a C2-C10 alkanediyl, preferably a C2-C9 alkanediyl, more preferably a C2-C7 alkanediyl, and even more preferably a C2-C5 alkanediyl.

[0096] Preferably, in compounds of formula (lia)) and (Ilia), Ra, Rb, Rc, identical or different, are a C1-C4 alkyl, preferably a C1-C4 alkyl.

[0097] Preferably, in compounds of formula (lia) and (Ilia), Ra and Rb are identical and are C1-C4 alkyl groups, preferably methyl, and Rc is ethyl. Preferably, in compounds of formula (lia) and (Ilia), Ra, Rb, and Rc, whether identical or different, are methyl or ethyl.

[0098] According to a preferred embodiment of the invention, in the compounds of formula (lia) and (Ilia), Ra and Rb are methyl and Rc is ethyl.

[0099] Preferably, in the compounds of formulas (lia) and (Ilia), the four groups of formula (lia) chosen from Ri to Rs other than that designating the group of formula (IV) and the six groups of formula (Ilia) chosen from Ri to R? other than that designating the group of formula (IV), identical or different, represent independently of each other, a hydrogen atom or an aliphatic hydrocarbon chain, saturated, linear or branched, in C1-C24.

[0100] More preferably still, in the compounds of formulas (lia) and (Ilia), the four groups of formula (lia) chosen from Ri to Rs other than that designating the group of formula (IV) and the six groups of formula (Ilia) chosen from Ri to R? other than that designating the group of formula (IV), identical or different, are chosen from the group consisting of the hydrogen atom, the alkyls in C1-C12, preferably in C1-C2, more preferably in C1-C4.

[0101] More preferably still, in the compounds of formulas (lia) and (Ilia), the four groups of formula (lia) chosen from Ri to R5 other than that designating the group of formula (IV) and the six groups of formula (Ilia) chosen from Ri to R7 other than that designating the group of formula (IV), identical or different, represent independently of each other, a hydrogen atom or a methyl.

[0102] According to a preferred embodiment of the invention, in formula (Ila), R2 represents a group of formula (IV) and Ri, R3, R4 and R5, identical or different, represent a hydrogen atom or an aliphatic hydrocarbon chain, preferably saturated, linear or branched, in C1-C24. More preferably, R2 represents a group of formula (IV) and Ri, R3, R4 and R5, identical or different, are chosen from the group consisting of a hydrogen atom and an alkyl in C1-C12, more preferably in C1-C2, more preferably in C1-C4.

[0103] More preferably in this embodiment, R2 represents a group of formula (IV), R4 represents a hydrogen atom, and Ri, R3, and R5 represent an aliphatic hydrocarbon chain, preferably saturated, linear or branched, in C1-C24. More preferably still, R2 represents a group of formula (IV), R4 represents a hydrogen atom, and Ri, R3, and R5, identical or different, represent an alkyl group in C1-C12, more preferably in C1-C2, more preferably in C1-C4.

[0104] According to another preferred embodiment of the invention, in formula (Ilia), Ri represents a group of formula (IV) and R2 to R7, identical or different, represent a hydrogen atom or an aliphatic hydrocarbon chain, preferably saturated, linear or branched, in the C1-C24 configuration. More preferably, Ri represents a group of formula (IV) and R2 to R7, identical or different, are selected from the group consisting of a hydrogen atom and an alkyl group in the C1-C12 configuration, more preferably in the C1-C2 configuration, and more preferably in the C1-C4 configuration. Even more preferably in this embodiment, Ri represents a group of formula (IV) and R2 to R7, identical, represent a hydrogen atom.

[0105] Preferably, the compound of formula (I) may be the compound of formula (lia) in which the group R2 is the group of formula (IV) with the group E representing a C2-C9 alkanediyl, more preferably a C2-C7 alkanediyl, more preferably a C2-C5 alkanediyl, the groups Ra, Rb, Rc identical or different, are a C1-C4 alkyl, preferably a C1-C4 alkyl, more preferably are chosen from the methyl and ethyl groups, the group R4 represents a hydrogen atom and the groups Ri, R3, R5 identical or different, represent a C1-C4 alkyl, preferably a C1-C4 alkyl, more preferably the methyl group.

[0106] Surprisingly, the compounds of the invention described above allow access to elastomeric compositions exhibiting a good compromise between stiffness, hysteresis, and tensile strength, while maintaining good dispersion of the inorganic reinforcing filler. Also surprisingly, they allow access to compositions using little or no polysulfide-silane coupling agents. Advantageously, this results in a lower manufacturing cost for these elastomeric compositions.

[0107] A particularly preferred compound of formula (la) is the compound of formula (V):

[0108] Among the compounds of formula (I), the compounds of formula (Ib) below are of particular interest because they are preferred synthetic intermediates of compounds of formula (la):

[0109] (Ib) with:

[0110] A represents a CÔ-CU arenediyl ring, possibly substituted by one or more identical or different aliphatic hydrocarbon chains, preferably saturated, linear or branched; E represents a C2-C12 divalent hydrocarbon group possibly comprising one or more heteroatoms; and

[0111] Ra, Rb, Rc, whether identical or different, represent an alkyl in C1-CO.

[0112] The preferred modes of A, E, Ra, Rb and Rc described for formulas (I), (II) and (III) also apply to compounds of formula (Ib).

[0113] The compounds with the above formulas (the) are also of particular interest because they are also synthetic intermediates of the preferred compounds with the formula (the):

[0114] (the) with:

[0115] A represents an arenediyl ring in CÔ-CU, possibly substituted by one or more hydrocarbon chains, identical or different, aliphatic, preferably saturated, linear or branched;

[0116] E represents a divalent hydrocarbon group in the C2-C12 range, possibly comprising one or more heteroatoms; and

[0117] Ra, Rb, Rc, whether identical or different, represent an alkyl in C1-CO.

[0118] The preferred modes of A, E, Ra, Rb and Rc described for formulas (I), (II) and (III) also apply to compounds of formula (le).

[0119] Another object of the present invention relates to a process for preparing a compound of formula (la) comprising at least one reaction (d) of a compound of formula (Ib) with a halogenating agent in the presence of at least one organic solvent SL1 according to the following reaction scheme: with: A represents an arenediyl ring in CÔ-CU, possibly substituted by one or more hydrocarbon chains, identical or different, aliphatic, preferably saturated, linear or branched;

[0120] E represents a divalent hydrocarbon group in the C2-C12 range, possibly comprising one or more heteroatoms; and

[0121] Ra, Rb, Rc, whether identical or different, represent an alkyl in C1-CO.

[0122] The preferred modes of A, E, Ra, Rb and Rc as described above, also apply to the process of preparing the compound of formula (la) from a compound of formula (Ib).

[0123] Preferably, the halogenating agent is chosen from the group consisting of N-bromosuccinimide in the presence of a base, N-chlorosuccinimide in the presence of a base, and sodium hypochlorite. Preferably, the base may be triethylamine. A halogenating agent is defined as a chemical compound that enables halogenation or dehalogenation reactions to occur via an addition or substitution mechanism.

[0124] Advantageously, the amount of halogenating agent is in the range of 1 to 5 molar equivalents, preferably 1 to 2 molar equivalents relative to the molar amount of the compound of formula (Ib).

[0125] Preferably, the organic solvent SL1 is chosen from chlorinated solvents, ester-type solvents, ether-type solvents and alcohol-type solvents, more preferably chosen from dichloromethane, trichloromethane, ethyl acetate, butyl acetate, diethyl ether, isopropanol and ethanol, even more preferably is chosen from ethyl acetate, trichloromethane, dichloromethane and butyl acetate.

[0126] Preferably, at the start of the reaction, the compound of formula (Ib) represents from 1% to 30% by weight, preferably from 1% to 20% by weight, relative to the total weight of the assembly comprising said compound of formula (Ib), said organic solvent SL1 and said halogenating agent.

[0127] The compound of formula (Ib) can in particular be obtained from a preparation process comprising at least one reaction (c) of at least one compound of formula (le) with an aqueous solution of hydroxylamine NH2OH (compound of formula (VI)) according to the following reaction scheme:

[0128] with :

[0129] A represents an arenediyl ring in CÔ-CU, possibly substituted by one or more hydrocarbon chains, identical or different, aliphatic, preferably saturated, linear or branched;

[0130] E represents a divalent hydrocarbon group in the C2-C12 range, possibly comprising one or more heteroatoms; and

[0131] Ra, Rb, Rc, whether identical or different, represent an alkyl in C1-CO.

[0132] The preferred modes of A, E, Ra, Rb and Rc as described above, also apply to the process of preparing a compound of formula (Ib) from a compound of formula (le).

[0133] Preferably, F hydroxylamine (compound of formula (VI)) can be added to the reaction medium at a temperature within a range of 1°C to 100°C, more preferably within a range of 20°C to 70°C.

[0134] The compound of formula (le) can be obtained by a preparation process comprising at least one hydrosilylation reaction (b) of the compound of formula (VII) with a compound of formula (VIII), preferably in the presence of an organometallic catalyst, according to the following reaction scheme: with :

[0135] A represents an arenediyl ring in CÔ-CU, possibly substituted by one or more hydrocarbon chains, identical or different, aliphatic, preferably saturated, linear or branched;

[0136] E represents a divalent hydrocarbon group in C2-C12 possibly comprising one or more heteroatoms;

[0137] Ra, Rb, Rc, whether identical or different, represent an alkyl group in the form C1-CO; and

[0138] Ei represents a group -(CH2)n-CH=CH2 with n an integer from 0 to 10, preferably from 0 to 8, more preferably from 0 to 7, more preferably still from 0 to 3.

[0139] The preferred modes of A, E, Ra, Rb and Rc also apply to the process of preparing a compound of formula (the) from the compound of formula (VIII) and the compound of formula (VII).

[0140] The reaction between the compound of formula (VIII) and that of formula (VII) can generally be carried out, in particular, in the presence of an organometallic catalyst and preferably at a temperature within the range of 0°C to 150°C, preferably within the range of 20°C to 80°C. The organometallic catalyst may be a platinum-based organometallic complex, such as, in particular, a Karstedt catalyst or a Speier catalyst.

[0141] Preferably, one can introduce into the reaction medium, for example, less than 1000 ppm, preferably less than 500 ppm of platinum calculated with respect to the total mass of compound (VIII) and of compound of formula (VII).

[0142] Compounds of formula (VII) as defined above are commercially available from suppliers such as Sigma-Aldrich, Merk, Chimieliva, etc. Compound of formula (VIII) can be obtained by nucleophilic substitution of a halogenated compound of formula (IX) by an alcohol compound of formula (X) according to the following reaction scheme: with

[0143] A represents an arenediyl ring in CÔ-CU, possibly substituted by one or more hydrocarbon chains, identical or different, aliphatic, preferably saturated, linear or branched;

[0144] Ei represents a group -(CH2)n-CH=CH2 with n an integer from 0 to 10, preferably from 0 to 8, more preferably from 0 to 7, and even more preferably from 0 to 3; and

[0145] X represents a halogen atom chosen from the group consisting of bromine, iodine and chlorine, preferably bromine.

[0146] Preferably, this reaction takes place in the presence of a Brønsted base such as, for example, a tertiary amine of the triethylamine type, or a mineral base of the potassium or sodium carbonate type, or even with potassium or sodium hydroxide. Preferably, this reaction takes place at a temperature in the range of 20°C to 150°C, more preferably in the range of 30°C to 100°C, and even more preferably in the range of 35°C to 70°C.

[0147] The compounds of formula (IX) and (X) are commercially available from suppliers such as Sigma Aldrich, ABCR.

[0148] As explained previously, the compounds of formula (la) and its preferred embodiments, in particular the compound of formula (V), are used as functionalizing agents. They can be grafted onto one or more polymers comprising at least one unsaturated carbon-carbon bond; in particular, this polymer may be an elastomer, and more especially a diene elastomer. The compounds of the invention advantageously allow the production of grafted polymers (also called modified polymers), in particular grafted diene elastomers, regardless of the initial microstructure of the polymer, the only condition being that the polymer comprises at least one unsaturated carbon-carbon bond, preferably a carbon-carbon double bond.The grafting of the polymer, comprising at least one unsaturated carbon-carbon bond, is carried out by reacting the initial polymer with the compound of formula (la) and its preferred embodiments, in particular the compound of formula (V). The grafting of these compounds is performed by [3+2] cycloaddition of the nitrile oxide group of said compounds to an unsaturated carbon-carbon bond of the polymer chain. The mechanism of this cycloaddition is illustrated in particular in document WO2012 / 007441 A1, specifically on page 13. During this reaction, said compound of formula (la) and its preferred embodiments, in particular the compound of formula (V), forms covalent bonds with the polymer chain.

[0149] The grafting of the compound of formula (la) and its preferred embodiments, in particular the compound of formula (V), can be carried out in bulk, for example in an internal mixer or in an external mixer such as a roller mixer, or can be carried out in solution. The grafting process can be performed in solution continuously or batchwise. The modified polymer can be separated from its solution by any means known to those skilled in the art, and in particular by steam stripping.

[0150] For the purposes of this invention, the term "initial polymer chain" refers to the polymer chain prior to the grafting reaction; this chain comprises at least one unsaturated carbon-carbon bond capable of reacting with the compound of formula (la) described above. The initial polymer is therefore the polymer used as the starting reagent in the grafting reaction. The grafting reaction allows a modified polymer to be obtained from an initial polymer. Preferably, the initial polymer can be an elastomer, and even more preferably, a diene elastomer.

[0151] Another object of the present invention is a composition based on an additive and at least one compound of formula (la) defined previously (and its preferred embodiments, in particular the compound of formula (V)). Preferably, the additive can be any additive commonly used in elastomeric compositions, particularly those intended for use in tires.The additives usable in the composition according to the invention may be a polymer, preferably an elastomer, more preferably a diene elastomer, 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 (such 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.

[0152] EXAMPLES OF THE INVENTION'S IMPLEMENTATION

[0153] The following examples illustrate the invention, but the latter cannot be limited to these examples alone.

[0154] 1 - Synthesis of compounds:

[0155] Mesitylene, paraformaldehyde, hydrochloric acid, acetic acid, dichloromethane (DCM), petroleum ether, titanium tetrachloride, dichloromethyl methyl ether (DCMME), 2-methylimidazole, N,N-dimethylformamide (DMF), ethanol, F-hydroxylamine, sodium hypochlorite (NaOCl), allyl bromide, 2,4,6-trimethylphenol, potassium carbonate, anhydrous toluene, xylene, ethyl acetate, triethylamine, N-bromosuccinimide, sodium sulfate are marketed by Fisher Scientific.

[0156] Fe triethoxysilane, Karstedt catalyst, dimethylethoxysilane are marketed by Merck.

[0157] 1.1 - Synthesis of compound A:

[0158] Fe compound 1,3-dipolar N-oxide 2,4,6-trimethyl-3-((2-methyl-1H-imidazol-1-yl)methyl)benzonitrile (compound A) can be prepared according to the following reaction scheme:

[0159] 1.1.1 - Synthesis of 2-(chloromethyl)-1,3,5-trimethylbenzene:

[0160] This compound can be obtained according to a procedure described in the following article: Zenkevich, IG; Makarov, AA; Russian Journal of General Chemistry; vol. 77; nb. 4; (2007); p. 611-619 (Zhurnal Obshchei Khimii; vol. 77; nb. 4; (2007); p. 653-662)

[0161] A mixture of mesitylene (100.0 g, 0.832 mol), paraformaldehyde (26.2 g, 0.874 mol) and hydrochloric acid (240 ml, 37%, 2.906 mol) in acetic acid (240 ml) is stirred and heated very slowly (1.5 hours) to 37°C.

[0162] After returning to room temperature (23°C), the mixture is diluted with water (1.0 L) and CH2Q2 (200 mL). The product is extracted with CH2Q2 (4 times per 50 mL). The organic phases are collected, then washed with water (5 times per 100 mL) and evaporated to 11-12 mbar (bath temperature = 42°C).

[0163] A colorless oil (133.52 g, yield 95%) is obtained.

[0164] After 15-18 hours at a temperature of +4°C, the oil crystallized. The crystals were filtered, washed with petroleum ether cooled to -18°C (40 ml), and then dried for 3 to 5 hours under atmospheric pressure at room temperature (23°C).

[0165] A white solid (95.9 g, 68% yield) with a melting point of 39 °C is obtained. The molar purity is superior [Table 1]

[0166] Analysis carried out in the CDCL

[0167] 1.1.2 - Synthesis of 3-(chloromethyl)-2,4,6-trimethylbenzaldehyde:

[0168] This compound can be obtained according to a procedure described in the following article: Yakubov, AP; Tsyganov, DV; Belen'kii, LI; Krayushkin, MM; Bulletin of the Academy of Sciences of the USSR, Division of Chemical Science (English Translation); vol. 40; nb. 7.2; (1991); p. 1427 - 1432 (Izvestiya Akademii Nauk SSSR, Senya Khimicheskaya; nb. 7; (1991); p. 1609 - 1615)

[0169] A solution of 2-(chloromethyl)-1,3,5-trimethylbenzene (20.0 g, 0.118 mol) and dichloromethyl methyl ether (27.26 g, 0.237 mol) in dichloromethane (200 ml) is added under argon for 10-12 minutes.

[0170] After stirring for 15–20 minutes at 17–20 °C, water (1000 mL) and ice (500 g) are added to the reaction mixture. After 10–15 minutes of stirring, the organic phase separates. The aqueous phase is extracted with CH₂Q₂ (3 times per 75 mL). The combined organic phases are washed with water (4 times per 100 mL) and evaporated under reduced pressure to obtain a solid (bath temperature = 28 °C).

[0171] The target product (22.74 g) is obtained with a yield of 97% and has a melting point of 58 °C.

[0172] Molar purity estimated by NMR is 95%.

[0173] [Table 2]

[0174] 1.1.3 - Synthesis of 2,4,6-trimethyl-3-((2-methyl-1H-imidazol-1-yl)methyl)benzaldehyde: A mixture of 3-(chloromethyl)-2,4,6-trimethylbenzaldehyde (10.0 g, 0.051 mol) and 2-methylimidazole (10.44 g, 0.127 mol) in DMF (10 ml) is stirred at 80°C for one hour.

[0175] After cooling to 40-50°C, the mixture is diluted with water (200 mL) and stirred for 10 minutes. The resulting precipitate is filtered and washed with water (4 times per 25 mL) and then dried at room temperature (23°C). A white solid (7.92 g, 64% yield) with a melting point of 161°C is obtained. The molar purity is 91% (NMR). 1 H).

[0176] [Table 3]

[0177] 1.1.4 - Synthesis of 2,4,6-trimethyl-3-((2-methyl-1H-imidazol-1-yl)methyl)benzaldehyde oxime:

[0178] To a solution of 2,4,6-trimethyl-3-((2-methyl-1H-imidazol-1-yl)methyl)benzaldehyde (20.3 g, 0.084 mol) in ethanol (110 ml) at 40°C, an aqueous solution of hydroxylamine (809 g, 0.134 mol, 50% in water, Aldrich) in ethanol (10 ml) is added.

[0179] The reaction mixture is stirred for 2.5 hours at a temperature of 50°C to 55°C. After cooling to 23°C, the resulting precipitate is filtered and washed twice on the filter with an ethanol / water mixture (10 mL / 15 mL) and dried for 15 to 20 hours under atmospheric pressure at room temperature (23°C, 1 atm). A white solid (19.57 g, 91% yield) with a melting point of 247°C is obtained. The molar purity is greater than 87% (NMR). 1 H).

[0180] [Table 4] Tl

[0181] Analysis carried out in the CDCh

[0182] 1.1.5 - Synthesis of 2,4,6-trimethyl-3-((2-methyl-1H-imidazol-1-yl)methyl)benzonitrile oxide:

[0183] To a mixture of 2,4,6-trimethyl-3-((2-methyl-1H-imidazol-1-yl)methyl)benzaldehyde oxime (8.80 g, 0.034 mol) in CH2Q2 (280 mL) at 6°C, an aqueous solution of NaOCl (4% active chlorine (w / w), 49 mL) is added dropwise over 5 minutes. The temperature of the reaction mixture is maintained between 6°C and 8°C.

[0184] The reaction mixture is then stirred for 2 hours at 8 °C to 21 °C. The organic phase is separated.

[0185] The organic phase is washed with water (3 times per 50 ml). After concentration under reduced pressure (bath temperature = 22-23°C, 220 mbar), petroleum ether (10 ml) is added, the solvent is evaporated to 8-10 ml, and the solution is maintained at -18°C for 10-15 hours to obtain a precipitate.

[0186] The precipitate is filtered and washed on the filter by the mixture of CH2Q2 / petroleum ether (2 ml / 6 ml) then by petroleum ether (2 times 10 ml) and finally dried for 10-15 hours under atmospheric pressure (1 atm) at room temperature (23°C).

[0187] A white solid (5.31 g, yield 61%) with a melting point of 139 °C is obtained. The molar purity is greater than 95% (NMR ^j.

[0188] [Table 6]

[0189] 1.2 - Synthesis of compound B:

[0190] The 1,3-dipolar N-oxide compound of 3-(3-(Ethoxydimethylsilyl)propoxy)-2,4,6-trimethylbenzonitrile, compound B, is synthesized according to the following protocol:

[0191] 1.2.1 - Synthesis of 3-hydroxy-2,4,6-trimethylbenzaldehyde (product Bl):

[0192] Compound Bl can be obtained according to a procedure described in the following article: Yakubov, AP; Tsyganov, DV; Belen'kii, L. / .; Krayushkin, MM; Bulletin of the Academy of Sciences of the USSR, Division of Chemical Science (English Translation); vol. 40; nb. 7.2;

[0193] (1991); p. 1427 - 1432; Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya; nb. 7; (1991); p. 1609 — 1615. 1.2.2 - Synthesis of 3-(allyloxy)-2,4,6-trimethylbenzaldehyde (product Cl):

[0194] A suspension of compound B1 (19.0 g, 115.7 mmol), allyl bromide (15.4 g, 127.3 mmol), and potassium carbonate (14.4 g, 104.1 mmol) in DMF (80 mL) is heated to 75°C for 30–40 minutes. After 3–4 hours of stirring at this temperature and after returning to room temperature (23°C, latm), the reaction mixture is filtered to remove the potassium carbonate. The filtrate is poured onto cold water at 3–4°C (700 mL). The target product is extracted four times per 100 mL of tert-butyl methyl ether.

[0195] The organic solutions are combined and washed twice with a 5% (w / mL) sodium hydroxide solution (50 mL) and then twice with water (50 mL). The organic solution is concentrated under reduced pressure (2 mbar, 40°C) to yield an oil (21.9 g).

[0196] After purification on a silica column (diameter 0.45 cm x 51 cm) using a mixture of ethyl acetate and petroleum ether as the eluent in a ratio of 1:20 to 1:15, the combined organic solutions were concentrated under reduced pressure (0 mbar, 40°C). A colorless oil (20.19 g) was obtained with a yield of 85.4% and a molar purity greater than 97% (NMR).

[0197] [Table 7]

[0198] Analysis carried out in the CDCh

[0199] 1.2.3 - Synthesis of 3-(3-(ethoxydimethylsilyl)propoxy)-2,4,6-trimethylbenzaldehyde (product D):

[0200] To a solution of 3-(allyloxy)-2,4,6-trimethylbenzaldehyde (compound Cl obtained previously) (6.00 g, 29.37 mmol) in anhydrous toluene (28 mL) at room temperature (23°C, 1 atm) under an argon atmosphere, dimethylethoxysilane (4.29 g, 41.12 mmol) is added. A solution of Karstedt catalyst (2.0%–2.4% wt. in xylene) (0.400 g) in anhydrous toluene (2 mL) is added in small portions over 10–15 minutes to the reaction mixture heated to 35°C.

[0201] After 10 minutes of stirring at this temperature, the reaction mixture is heated to 50–55°C. After 4 hours of stirring at this temperature, followed by a return to room temperature, the reaction mixture is concentrated under reduced pressure (9 mbar, 40°C) to yield an oil (9.5 g). This oil proceeds to the next step without further purification, achieving a purity of 73 molar (NMR). 1 H, CDCh).

[0202] [Table 8]

[0203] Analyses performed in CDCh

[0204] 1.2.4 - Synthesis of 3-(3-(ethoxydimethylsilyl)propoxy)-2,4,6-trimethylbenzaldehyde oxime (product E): To a solution of compound D obtained in the previous step (~29.4 mmol) in absolute ethanol (110 ml) at room temperature is added a 50% wt% hydroxylamine solution in water (2.91 g, 44.1 mmol) diluted in absolute ethanol (10 ml).

[0205] After 30-40 minutes of stirring at room temperature, the reaction mixture is concentrated under reduced pressure (20 mbar, 30°C) to yield a cloudy oil (11.55 g). This residue is then resuspended in petroleum ether (40 mL). The solution is filtered through a silica gel filter (diameter 0.35 cm, thickness 0.5-0.7 cm), and the residue is washed twice on the filter with petroleum ether (10 mL).

[0206] The solution is concentrated under reduced pressure (2 mbar, 30°C) to produce a colorless oil. The pure target product is obtained after purification on a silica column (diameter 0.45 cm x 47 cm; eluent ethyl acetate / petroleum ether: 1 / 10 to 18 (v / v)).

[0207] The solution is concentrated under reduced pressure (0 to 1 mbar, 40°C) to produce a colorless oil (4.547 g, 14.06 mmol) with a yield of 51% and a molar purity of 94%.

[0208] [Table 9]

[0209] Analyses performed in CDCh

[0210] 1.2.5 - Synthesis of 3-(3-(Ethoxydimethylsilyl)propoxy)-2,4,6-trimethylbenzonitrile N-oxide (compound B):

[0211] Triethylamine (1.99 g, 19.6 mmol) was added to a solution of compound E obtained in the previous step (4.52 g, 13.14 mmol) in dichloromethane (65 mL). The mixture was stirred under nitrogen and then cooled to 0°C. N-Chloro succinimide (2.11 g, 15.76 mmol) was then added to the mixture when the reaction temperature reached 0°C.

[0212] After 25–30 minutes of stirring at 0°C, the reaction mixture is washed twice with water (15 mL). The organic solution is dried over sodium sulfate and concentrated under reduced pressure (9 mbar, 18°C) to yield 5.41 g of a yellow / orange oil. This oil is reconstituted in a mixture of ethyl acetate (10 mL) and petroleum ether (60 mL). The solution is filtered through a silica gel filter (3.5 cm diameter x 1.0 cm diameter) and washed with a mixture of ethyl acetate (5 mL) and petroleum ether (25 mL).

[0213] The colorless permeate is concentrated under reduced pressure (0 mbar, 18 °C, 1 hour) to yield, with a 97% yield, an oil (12.78 mmol, 4.108 g) with a molar purity greater than 97% (NMR). 1 H).

[0214]

[0215] [Table 10]

[0216] Analysis performed in CDCh 1.3. - Characterization of the synthesized compounds:

[0217] Structural analysis and molar purity determination of the synthetic molecules are performed by NMR analysis. Spectra are acquired on a Bruker Avance 3400 MHz spectrometer equipped with a 5 mm BBFO-zgrad broadband probe. The quantitative ¹H 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 chloroform (CDCL), unless otherwise specified. The deuterated solvent is also used for the lock signal. For example, calibration is performed on the proton signal of deuterated CDCL at 7.20 ppm relative to a TMS reference at 0 ppm. The ¹H NMR spectrum is coupled to the 2D HSQC experiments. allow the structural determination of molecules. Molar quantifications are performed from the spectrum quantitative.

[0218] 2 - Synthesis of the elastomer:

[0219] The polymerization of ethylene (N35 grade from Air Liquide, used without prior purification) and 1,3-butadiene is carried out by a continuous process in solution in methylcyclohexane at 80°C under 11.5 bar in the presence of a catalytic system (94 pmoles Nd for 100 g of monomers), the mass concentration of monomer feed into the reactor being 6%, the mass ratio 1,3-butadiene / ethylene being 0.53, the molar ratio active Mg / Nd being 3.7. At the desired conversion (73%, 120 minutes) to reach a Mn of approximately 138000 g / mol, the polymerization is stopped at the line outlet using a solution of antioxidants in methylcyclohexane (0.6 pc of N-(l,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine and 0.7 pc of 2,2'-methylene-bis(4-methyl-6-tert-butylphenol).The copolymer is recovered by a steam entrainment process called "stripping" well known to those skilled in the art, then dried on a screw conveyor equipped with a single screw.

[0220] The catalytic system is a preformed catalytic system. It is prepared in methylcyclohexane from a metallocene, [Me2Si(Flu)2Nd(p-BH4)2Li(THF)] at 0.0065 mol / L, a co-catalyst, butylmagnesium (BOMAG) with a BOMAG / Nd molar ratio of 2.2, and a preforming monomer, 1,3-butadiene with a 1,3-butadiene / Nd molar ratio of 90. The medium is heated to 80°C for 5 hours. It is prepared according to a method conforming to section II.1 of document WO2017093654A1.

[0221] The resulting elastomer has the following microstructure: 7 mol% polybutadiene 1,4- units, 11 mol% polybutadiene 1,2- units, 75 mol% ethylene, and 7 mol% 1,2-cyclohexanediyl units. The elastomer has a Tg of -43°C, a Mn of 138,000 g / mol measured by the method described below, and a Mooney (ML (1+4)) at 100°C of 64 MU (see measurement method below).

[0222] 3 - Determination of the microstructure of elastomers:

[0223] The microstructure of elastomers is determined by NMR analysis 1 H, supplemented by NMR analysis 13 C when the resolution of the NMR spectra of the This method does not allow for the identification and quantification of all species. Measurements are performed using a BRUKER 500 MHz NMR spectrometer at frequencies of 500.43 MHz for proton observation and 125.83 MHz for carbon observation. A liquid NMR probe enabling observation of both protons and carbon in proton-decoupled mode is used.

[0224] The preparation of insoluble samples is carried out in rotors filled with the material to be analyzed and a deuterated solvent that induces swelling, generally deuterated chloroform (CDCL). The solvent used must always be deuterated, and its chemical composition can be adapted by those skilled in the art. The quantities of material used are adjusted to obtain spectra with sufficient sensitivity and resolution.

[0225] Soluble samples are dissolved in a deuterated solvent (approximately 25 mg of elastomer in 1 ml), generally deuterated chloroform (CDCL). The solvent or solvent cutting agent used must always be deuterated, and its chemical composition can be adapted by a person skilled in the art.

[0226] In both cases (soluble sample or swollen sample):

[0227] For proton NMR, a single 30° pulse sequence is used. The spectral window is adjusted to observe all the resonance lines belonging to the analyzed molecules. The accumulation number is set to obtain a signal-to-noise ratio sufficient for quantifying each motif. The recycling time between each pulse is adjusted to obtain a quantitative measurement.

[0228] For carbon NMR, a simple 30° pulse sequence is used with proton decoupling only during acquisition to avoid Nuclear Overhauser Effects (NOE) and maintain quantitative accuracy. The spectral window is adjusted to observe all resonance lines belonging to the analyzed molecules. The accumulation number is set to obtain a signal-to-noise ratio sufficient for quantifying each motif. The recycle time between each pulse is optimized for quantitative measurement.

[0229] NMR measurements are performed at 25°C.

[0230] 4 - Determination of the Tg of elastomers:

[0231] The glass transition temperature (Tg) values ​​described herein are measured in a known manner by DSC (Differential Scanning Calorimetry) according to ASTM D3418-2008.

[0232] 5 - Determination of the Mn of elastomers: Measurement of the Mn, Mw and Ip of elastomers by triple detection size exclusion chromatography (SEC-3D)

[0233] The number-average molar mass (Mn), and where applicable the weight-average molar mass (Mw) and the polydispersity index (Ip) of the elastomers are determined in a known manner, by triple-detection size exclusion chromatography “SEC-3D” (SEC: “Size Exclusion Chromatography”).

[0234] Triple detection size exclusion chromatography has the advantage of measuring average molar masses directly without calibration.

[0235] The refractive index increment dn / dc of the sample is determined first. To do this, the sample is first solubilized in tetrahydrofuran at precisely known concentrations (0.5 g / L, 0.7 g / L, 0.8 g / L, 1 g / L, and 1.5 g / L). Each solution is then filtered through a 0.45 µm pore size filter. Each solution is then injected directly, using a syringe pump, into a Wyatt Technology differential refractometer, commercially known as the "OPTILAB T-REX," with a wavelength of 658 nm and a temperature of 35°C. The refractive index is measured by the refractometer at each concentration. Wyatt Technology's "ASTRA" software plots the detector signal against the sample concentration.The "ASTRA" software automatically determines the slope of the line corresponding to the refractive index increment of the sample in tetrahydrofuran at 35°C and a wavelength of 658 nm.

[0236] To determine the average molar masses, the previously prepared and filtered 1 g / L solution is injected into the chromatographic system. The equipment used is a WATERS alliance chromatographic system. The elution solvent is oxidized tetrahydrofuran, with 250 ppm BHT (2,6-diter-butyl 4-hydroxytoluene), at a flow rate of 1 mL / min. 1The system temperature was 35°C and the analysis time 60 min. The columns used were a set of three AGILENT columns, commercially known as "PL GEL MIXED B LS". The injected volume of the sample solution was 100 µL. The detection system consisted of a Wyatt Technology differential viscometer, commercially known as "VISCOSTAR II", a Wyatt differential refractometer, commercially known as "OPTILAB T-REX" with a wavelength of 658 nm, and a Wyatt Technology multi-angle static light scattering detector, commercially known as "DAWN HELEOS 8+", with a wavelength of 658 nm.

[0237] For the calculation of the number-average molar masses and the polydispersity index, the value of the refractive index increment dn / dc of the sample solution obtained above is incorporated. The chromatographic data processing software is the "ASTRA" system from Wyatt Technology.

[0238] 6 - Determination of the Mooney viscosity ML(l+4) at 100°C according to ASTM D-1646 for elastomers:

[0239] A consistometer is used as described in ASTM D-1646 (1999). The Mooney viscosity measurement is performed according to the following principle: the elastomer is molded in a cylindrical chamber heated to 100 °C. After one minute of preheating, the rotor rotates within the specimen at 2 revolutions per minute, and the torque required to maintain this rotation after 4 minutes of rotation is measured. The Mooney viscosity (ML(l+4)) is expressed in Mooney Units (MU, with 1 MU = 0.83 Nm).

[0240] 7 - Grafting the compounds onto an elastomer:

[0241] 7.1 - Elastomer grafted with compound A:

[0242] Compound A (N-oxide 2,4,6-trimethyl-3-((2-methyl-1H-imidazol-1-yl)methyl)benzonitrile) obtained according to the process described in paragraph 1.1 (0.3% mol i.e. 2.12 g) is incorporated into 100 g of EBR elastomer obtained according to the process described in paragraph 2.

[0243] The incorporation is carried out using a roller tool (external mixer at 30°C). The mixture is homogenized fifteen times on this tool.

[0244] This mixing phase is followed by a heat treatment (10 min at 120°C) under a press at 10 bars of pressure.

[0245] Following the two processing steps, the analysis by NMR enabled the determination of a molar rate of grafted nitrile oxide (CNO) function of 0.16 mol%, i.e. a molar grafting yield of 80%.

[0246] 7.2 - Elastomer grafted with compound B:

[0247] Compound B (3-(3-(Ethoxydimethylsilyl)propoxy)-2,4,6-trimethylbenzonitrile N-oxide) obtained according to the process described in paragraph 1.3 (0.3% mol i.e. 2.65 g) is incorporated into 100 g of EBR obtained according to the process described in paragraph 2.

[0248] The incorporation is carried out using a roller tool (external mixer at 30°C). The mixture is homogenized fifteen times on this tool.

[0249] This mixing phase is followed by a heat treatment (10 min at 100°C) under a press at 10 bars of pressure.

[0250] Following the two processing steps, the analysis by NMR enabled the determination of a molar grafting rate of 0.16% mol with a molar grafting yield of 80%.

[0251] 7.3. Characterization of compounds grafted onto diene elastomers:

[0252] The molar content of compounds grafted onto diene elastomers was determined by NMR analysis. Spectra were acquired on a 500 MHz BRUKER spectrometer equipped with a CryoSonde BBEO-zgrad-5 mm. The quantitative 1H NMR experiment used a single 30° pulse sequence with a 5-second repetition interval between acquisitions. Samples were solubilized in deuterated chloroform (CDCh) to obtain a lock signal. 2D NMR experiments were used to verify the nature of the grafted motif by observing the chemical shifts of carbon and proton atoms.

[0253] 8 - Obtaining the elastomeric compositions: The elastomeric compositions, the detailed formulation of which is shown in the table below, were prepared as follows:

[0254] The grafted or ungrafted elastomer is introduced into an internal mixer (final filling rate: approximately 70% by volume), the initial temperature of which can be between 80°C and 100°C. Silica, carbon black, and the coupling agent for the inorganic filler are then added to the elastomer. After one to two minutes of mixing, the various other ingredients are added, with the exception of sulfur and the vulcanization accelerator. A thermomechanical process (non-productive phase) is then carried out in a single step, lasting approximately 5 to 6 minutes in total, until a maximum "drop" temperature of 160°C is reached.

[0255] The mixture thus obtained is collected, cooled, and then sulfur and vulcanization accelerator are incorporated on a roller tool at 23°C, mixing the mixture and these ingredients (productive phase) for an appropriate time of 8 minutes.

[0256] The compositions thus obtained are then calendered from thin plates or sheets to measure their physical or mechanical properties.

[0257] The crosslinking was then carried out at a temperature of 150°C for 90 min, under pressure.

[0258] 9 - Dynamic properties of elastomeric compositions:

[0259] Dynamic properties are measured on a viscoelastic analyzer (Metravib VA4000), according to ASTM D 5992-96. The response of a cross-linked composite sample (a 4 mm thick cylindrical specimen molded between 3 coated steel blocks and 10 mm in diameter) is recorded, subjected to sinusoidal loading in alternating simple shear, at a frequency of 10 Hz, under defined temperature conditions (e.g., 60°C or 100°C) according to ASTM D 1349-99. A strain amplitude sweep is performed from 0.1% to 100% (forward cycle), then from 100% to 0.1% (reverse cycle).

[0260] The results used are the complex shear modulus G*, the loss factor tan(θ), and the modulus difference AG* between the values ​​of 0.1% and 100% strain (Payne effect), on the return cycle.

[0261] For the return cycle, we indicate the maximum value of tan(ô) observed at 60°C (noted tan(ô)max at 60°C) and the maximum value of tan(ô) observed at 100°C, noted tan(ô)max at 100°C; as well as the modulus G* at 25% deformation noted G*25% return at 60°C.

[0262] The values ​​of G*25% returning to 60°C are representative of the stiffness.

[0263] The values ​​of tan(ô) max return at 60°C and tan(ô) max return at 100°C are representative of the hysteresis.

[0264] The results are shown in base 100; the arbitrary value 100 is assigned to the control to calculate and then compare tan(ô) ma x at 100°C, tan(ô) max at 00°C, G*25% return to 00°C and AG* of the different samples tested. For tan(φ)max at 60°C, the value in base 100 for the sample to be tested is calculated according to the operation: (value of tan(φ) ma x at 60°C of the sample to be tested / value of tan(θ) ma x at 60°C of the control) x 100. The same calculation is performed with tan(θ) ma x at 100°C In this way, a result less than 100 indicates a decrease in hysteresis which corresponds to an improvement in rolling resistance performance.

[0265] For G*25% return at 60°C, the value in base 100 for the sample to be tested is calculated according to the operation: (value of G*25% return at 60°C of the sample to be tested / value of G*25% return at 60°C of the control) x 100. In this way, a result greater than 100 indicates an improvement in the complex dynamic shear modulus G*25% return at 60°C, which corroborates an improvement in the stiffness of the material.

[0266] For (AG*), the value in base 100 for the sample to be tested is calculated according to the operation: (value of AG* of the sample to be tested / value of AG* of the control) x 100. In this way, a result less than 100 reflects a decrease in the deviation of the modulus, i.e. an increase in the linearization of the elastomeric composition, i.e. a better dispersion of the reinforcing charge in the composition.

[0267] 10 - Tensile properties of elastomeric compositions:

[0268] These tensile tests determine the breaking properties. Unless otherwise specified, they are carried out in accordance with the French standard NF T 46-002 of September 1988.

[0269] The breaking stresses (in MP a) are measured at 100°C ± 2°C according to standard NF T 46- 002 and in true secant modulus.

[0270] The results are presented on a base of 100, with the arbitrary value 100 being assigned to the control for calculation and comparison to the value of the tested composition:

[0271] (value of the breaking stress of the sample to be tested / value of the breaking stress of the control) x 100. In this way, a result greater than 100 indicates an improvement in the breaking stress property.

[0272] 11 - Essay:

[0273] The purpose of this test is to show that the compound of the invention (compound B), once grafted onto a diene elastomer, gives the elastomeric compositions containing it a very good compromise of properties between the properties of stress at break, hysteresis and stiffness, while maintaining a good dispersion of the reinforcing charge.

[0274] The proportions of the different constituents of these compositions, expressed in parts per cent parts per hundred weight of elastomer, are presented in the table below.

[0275] The mechanical properties of the elastomeric compositions measured after baking are presented in the table below.

[0276] [Table 11]

[0277] (1) Ungrafted diene elastomer (2) Diene elastomer grafted with compound A according to the process described in paragraph 7.1

[0278] (3) Diene elastomer grafted with compound B of the invention according to the process described in paragraph 7.2

[0279] (4) Silica “Zeosil 1165MP” marketed by Solvay

[0280] (5) ASTM N234 grade carbon black (ASTM D1765-17) marketed by Cabot Corporation

[0281] (6) Coupling agent of the inorganic reinforcing agent to the elastomer: Bis[3-(triethoxysilyl)propyl] Tetrasulfide silane (TESPT) marketed by Evonik under the reference “Si69”

[0282] (7) Anti-ozone wax: “Varazon 4959” wax from Sasol Wax

[0283] (8) Antioxidant: ((N-(l,3-dimethylbutyl)-N-phenyl-para-phenylenediamine marketed under the reference "Santaflex 6-PPD" by the company Flexsys

[0284] (9) Stearic acid marketed under the reference "Pristerene 4931" by the company Uniqema

[0285] (10) Industrial grade zinc oxide marketed by Umicore

[0286] (11) Accelerator: N-cyclohexyl-2-benzothiazyl-sulfenamide: “Santicure CBS” from Flexsys

[0287] In the presence of a coupling agent for the inorganic reinforcing filler to the diene elastomer, grafting the compound of the invention (compound B) onto the diene elastomer yields an elastomeric composition (composition Cl) exhibiting improved linearity (Paye effect) and a good compromise between hysteresis, stiffness, and tensile strength compared to an elastomeric composition (composition Tl) without a grafted diene elastomer. These improvements in properties are of the same order of magnitude as those observed for an elastomeric composition comprising a diene elastomer grafted with a prior art 1,3-dipolar compound (comparison of compositions T3 versus Tl).

[0288] When the coupling agent of the inorganic reinforcing filler with F diene elastomeric in the elastomeric compositions (Compositions T2, T4 and C2) is removed, it is observed that only the elastomeric composition comprising the diene elastomer grafted with the compound of the invention (composition C2) exhibits an improvement in the stress-at-break properties while maintaining the improvement in linearity and the compromise of hysteresis / stiffness properties (see composition C2 versus Cl).

[0289] Thus, the compound of the invention makes it possible to modify a diene elastomer and to give the elastomeric compositions containing it a very good compromise of tensile strength, hysteresis and stiffness properties, while maintaining good dispersion of the reinforcing filler including when the elastomeric composition includes a small amount or no coupling agent of the inorganic reinforcing filler to the diene elastomer.

Claims

DEMANDS 1) Compound of the following formula (I): (I) in which: T is chosen from the group formed by CN + -O", CH=NOH and CHO; A represents an arenediyl ring in CÔ-CU, possibly substituted by one or more hydrocarbon chains, identical or different, aliphatic, preferably saturated, linear or branched; E represents a divalent hydrocarbon group in the C2-C12 range, possibly comprising one or more heteroatoms; and Ra, Rb, Rc, whether identical or different, represent an alkyl in C1-CO. 2) Compound of formula (I) according to claim 1, in which T is CH=NOH. 3) Compound of formula (I) according to claim 1, in which T is CHO. 4) Compound of formula (I) according to claim 1, wherein T is CN + -O". 5) Compound of formula (I) according to any one of claims 1 to 4, wherein E represents a divalent hydrocarbon group in C2-C10, preferably in C2-C9, more preferably in C2-C7, more preferably still in C2-C5. 6) Compound of formula (I) according to any one of claims 1 to 4, in which E represents a C2-C10 alkanediyl, preferably a C2-C9 alkanediyl, more preferably a C2-C7 alkanediyl, more preferably still a C2-C5 alkanediyl. 7) Compound of formula (I) according to any one of the preceding claims, wherein Ra, Rb, Rc, identical or different, represent a C1-C4 alkyl. 8) Compound of formula (I) according to any one of the preceding claims, wherein Ra and Rb are identical and are a C1-C4 alkyl, preferably methyl, and Rc is ethyl. 9) Compound of formula (I) according to any one of the preceding claims, which compound of formula (I) is selected from compounds of formula (II) and (III) in which: a grouping chosen from Ri to R5 of formula (II) and a grouping chosen from Ri to R7 of formula (III) denote the following group of formula (IV): (IV) wherein T, E, Ra, Rb, Rc are as defined in any one of claims 1 to 7 and the symbol (*) represents attachment to (II) or to (III), the four groups of formula (II) chosen from Ri to R5 other than that designating the group of formula (IV) and the six groups of formula (III) chosen from Ri to R7 other than that designating the group of formula (IV), identical or different, represent independently of each other, a hydrogen atom or an aliphatic hydrocarbon chain, preferably saturated, linear or branched in C1-C24. 10) Compound of formula (I) according to claim 1, which compound of formula (I) is the compound of formula (V): (V) 11) Composition based on at least one additive and at least one compound of formula (I) defined according to any one of claims 4 to 10. 12) Process for preparing a compound of formula (la), said process comprising at least one reaction of a compound of formula (Ib) with a halogenating agent in the presence of at least one organic solvent SL1 according to the following reaction scheme: with : A represents an arenediyl ring in CÔ-CU, possibly substituted by one or more hydrocarbon chains, identical or different, aliphatic, preferably saturated, linear or branched; E represents a divalent hydrocarbon group in the C2-C12 range, possibly comprising one or more heteroatoms; and Ra, Rb, Rc, whether identical or different, represent an alkyl in C1-CO. 13) A preparation process according to claim 12, said process further comprising at least one reaction of at least one compound of formula (l) with an aqueous solution of hydroxylamine NH2OH according to the following reaction scheme: with : A represents an arenediyl ring in CÔ-CU, possibly substituted by one or more hydrocarbon chains, identical or different, aliphatic, preferably saturated, linear or branched; E represents a divalent hydrocarbon group in the C2-C12 range, possibly comprising one or more heteroatoms; and Ra, Rb, Rc, whether identical or different, represent a C1-CO alkyl group. 14) A preparation process according to claim 13, said process further comprising at least one hydrosilylation reaction of the compound of formula (VII) with a compound of formula (VIII) according to the following reaction scheme: with : A represents an arenediyl ring in CÔ-CU, possibly substituted by one or more hydrocarbon chains, identical or different, aliphatic, preferably saturated, linear or branched; E represents a divalent hydrocarbon group in C2-C12 possibly comprising one or more heteroatoms; Ra, Rb, Rc, whether identical or different, represent an alkyl group in the form C1-CO; and Ei represents a group -(CH2)n-CH=CH2 with n an integer from 0 to 10, preferably from 0 to 8, more preferably from 0 to 7, more preferably still from 0 to 3. 15) A preparation process according to claim 14, said process further comprising a nucleophilic substitution reaction of a halogenated compound of formula (IX) by an alcohol compound of formula (X) according to the following reaction scheme: with A represents an arenediyl ring in CÔ-CU, possibly substituted by one or more hydrocarbon chains, identical or different, aliphatic, preferably saturated, linear or branched; Ei represents a group -(CH2)n-CH=CH2 with n an integer from 0 to 10, preferably from 0 to 8, more preferably from 0 to 7, and even more preferably from 0 to 3; and X represents a halogen atom chosen from the group consisting of bromine, fluorine, iodine and chlorine, preferably bromine.

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