FR3054230A1 - COMPOUND FOR A REINFORCING RESIN FOR A RUBBER COMPOSITION - Google Patents

Abstract

The compound is derived from the reaction between a reagent of formula A: and a reagent of formula B and / or C: in which: Ar represents an aromatic nucleus, optionally substituted, the radical R1 represents a monovalent radical chosen from the group consisting of alkyl, aryl, AL-NH2 radicals with AL representing a monovalent alkyl radical, AR-NH2 with AR representing a monovalent aryl radical, AL-NR2H with AL representing a monovalent alkyl radical and AR-NR2H with AR representing a monovalent radical aryl, - the radical R2 represents a monovalent hydrocarbon radical or a substituted monovalent hydrocarbon radical.

Description

Holder (s): COMPAGNIE GENERALE DES ETABLISSEMENTS MICHELIN Limited partnership with shares, MICHELIN RECHERCHE ET TECHNIQUE S.A. Limited company.

Extension request (s)

Agent (s): MANUF FSE PNEUMATIQUES MICHELIN Limited partnership with shares.

(04) COMPOUND FOR A REINFORCING RESIN FOR A RUBBER COMPOSITION.

(ü /) The compound results from the reaction between a reagent of formula A:

with AL representing a monovalent alkyl radical and ARNR ₂ H with AR representing a monovalent aryl radical,

the radical R ₂ represents a monovalent hydrocarbon radical or a monovalent substituted hydrocarbon radical.

Ar

FR 3 054 230 - A1 (A) and a reagent of formula B and / or C:

H

H ₂ NR ₂ -N-Ri (B) (C) in which:

- Ar represents an aromatic nucleus, optionally substituted,

- the radical R! represents a monovalent radical chosen from the group consisting of alkyl, aryl, AL-NH ₂ radicals with AL representing a monovalent alkyl radical, AR-NH ₂ with AR representing a monovalent aryl radical, AL-NR ₂ H

-1 [001] The invention relates to a compound, a manufacturing process and a use of this compound.

It is known to use, in certain parts of the tires, rubber compositions having high rigidity during slight deformations of the tire. Resistance to low deformation is one of the properties that a tire must have in order to respond to the stresses to which it is subjected.

High rigidity can be obtained using a so-called concentrated vulcanization system, that is to say comprising in particular relatively high sulfur and vulcanization accelerator levels.

[004] However, such a concentrated vulcanization system penalizes the raw aging of the composition. Thus, when the composition is in the form of a semi-finished product, for example a strip of gum, the sulfur can migrate to the surface of the semi-finished product. This phenomenon, called effleurage, leads to a penalization of the raw sticky of the semi-finished product during its prolonged storage, with as a consequence a degradation of the adhesion between the semi-finished products during the manufacture of the tire.

Furthermore, the storage of the raw composition containing a concentrated vulcanization system is likely to cause a reduction in the delay phase of the composition during its vulcanization, that is to say the time preceding the start of vulcanization. As a result, the composition may begin to cook prematurely in some shaping tools and the vulcanization kinetics may be changed and the vulcanization yield may be degraded.

[006] Such a concentrated vulcanization system also penalizes aging when cooked. Indeed, there is a degradation of the mechanical properties of the cooked composition, especially at the limits, for example of elongation at break.

High rigidity can otherwise be obtained by increasing the rate of reinforcing filler.

[008] However, in known manner, increasing the rigidity of a rubber composition by increasing the loading rate can penalize the hysteresis properties and therefore the rolling resistance of the tires. However, we are always trying to lower the rolling resistance of the tires to reduce fuel consumption and thus preserve the environment.

Finally, high rigidity can be obtained by incorporating certain reinforcing resins as disclosed in WO 02/10269.

[010] Conventionally, the increase in rigidity is obtained by incorporating reinforcing resins based on an acceptor / donor system of methylene. The terms "methylene acceptor" and "methylene donor" are well known to those skilled in the art and

-2 widely used to designate compounds capable of reacting together to generate by condensation a three-dimensional reinforcing resin which is superimposed and interpenetrated with the reinforcing filler / elastomer network on the one hand and, with the elastomer / sulfur network on the other hand (if the crosslinking agent is sulfur). With the methylene acceptor is associated a hardening agent, capable of crosslinking or hardening it, also commonly called methylene donor. Examples of such methylene acceptor and donor are described in WO 02/10269.

The methylene donors conventionally used in rubber compositions for tires are hexa-methylenetetramine (abbreviated HMT), or hexamethoxymethylmelamine (abbreviated HMMM or H3M), or hexaethoxymethylmelamine.

The methylene acceptors conventionally used in rubber compositions for tires are precondensed phenolic resins.

[013] However, the combination of phenolic resin conventionally used as a methylene acceptor with ΙΉΜΤ or ΙΉ3Μ as a methylene donor, produces formaldehyde during the vulcanization of the rubber composition. However, it is desirable to reduce or even eliminate formaldehyde from rubber compositions in the long term due to the environmental impact of these compounds and to recent regulatory developments, in particular European regulations, on this type of compound.

The aim of the invention is to provide a rigidified rubber composition by means of compounds with low environmental impact.

To this end, the subject of the invention is a compound resulting from the reaction between a reagent of formula A:

(A) and a reagent of formula B and / or C

H ₂ N (B)

(C) and mixtures of these compounds, in which:

- Ar represents an aromatic nucleus, optionally substituted,

- the radical R! represents a monovalent radical chosen from the group consisting of alkyl, aryl, AL-NH ₂ radicals with AL representing a monovalent alkyl radical,

3AR-NH ₂ with AR representing a monovalent aryl radical, AL-NR ₂ H with AL representing a monovalent alkyl radical and AR-NR ₂ H with AR representing a monovalent aryl radical,

the radical R ₂ represents a monovalent hydrocarbon radical or a monovalent substituted hydrocarbon radical.

Unexpectedly, the Applicants discovered during their research that the compound of the composition according to the invention makes it possible to avoid the production of formaldehyde, unlike conventional methylene donors. The Applicants discovered during their research that a compound could, with an aromatic polyphenol, form an alternative resin to reinforcing resins based on an acceptor / donor methylene system.

[017] In addition, the combination of the compound and the aromatic polyphenol according to the invention makes it possible to obtain rubber compositions having a rigidity at low deformation equivalent to or even greater compared to conventional rubber compositions which comprise methylene HMT donors or H3M and compared to rubber compositions devoid of reinforcing resin.

In addition, the aromatic polyphenols and compounds according to the invention also make it possible to avoid early crosslinking of the resin. Indeed, a problem linked to the use of certain reinforcing resins, in particular that based on the aromatic polyphenol and the aldehyde corresponding to the compound (the aldehyde of formula A), is their capacity to crosslink early. In fact, after the step of manufacturing the composition comprising the constituents of these reinforcing resins, the composition is shaped for example by calendering, for example in the form of a sheet, a plate, or even extruded, for example to form a rubber profile. However, because of their capacity to crosslink quickly, these reinforcing resins crosslink and stiffen the composition, which can hinder the shaping of the rubber composition. Thanks to the invention, the resin formed from the compound and the aromatic polyphenol is formed less quickly than from the corresponding aldehyde and aromatic polyphenol. This reaction speed can be determined by measuring the evolution of the rheometric torque as a function of time. This development describes the stiffening of the composition as a result in particular of the crosslinking of the resin. From the comparison of the evolution of the rheometric couples of a first composition comprising the aromatic polyphenol and the compound and of a second composition comprising the corresponding aromatic polyphenol and the aldehyde, it can be seen that the compound makes it possible to delay the crosslinking of the resin with respect to the direct reaction between the aromatic polyphenol and the corresponding aldehyde.

The inventors at the origin of the invention hypothesize that the compound is a precursor of the aldehyde (which would be the aldehyde of formula A) and that this compound makes it possible to avoid early crosslinking resin due to a reaction that would generate the aldehyde from the compound. In fact, the reagents of formulas B and C act as temporary protective reagents allowing, according to the inventors' hypothesis, the formation of each aldehyde function under predetermined reaction conditions and therefore the formation of the corresponding aldehyde (in others terms the regeneration of the aldehyde of formula A). The predetermined reaction conditions under which this formation is possible depend on several parameters such as pressure, temperature or even the chemical species present in the reaction medium. These reaction conditions are a function of the reagents of formulas B and C and are easily determinable, or even known to a person skilled in the art. For example, such reaction conditions are the heating of the rubber composition to a temperature greater than or equal to 80 ° C., preferably to 100 ° C. and more preferably to 120 ° C.

Thus, by following this hypothesis, we will speak in what follows indifferently of resin or of phenol-aldehyde resin to identify the resin based on polyphenol and on the compound resulting from the reaction of reactants A with B and / or C.

The reagents of formulas B and C are such that the reaction between the aromatic polyphenol and the compound allows the crosslinking of the resin. Preferably, the reagents of formulas B and C are such that the reaction between the aromatic polyphenol and the compound allows the crosslinking of the resin under the same reaction conditions, preferably the same temperature reaction conditions, as a phenol-aldehyde resin based on the same aromatic polyphenol and the corresponding aldehyde (that is to say the aldehyde of formula A). Conventionally, the temperature is greater than or equal to 120 ° C., preferably greater than or equal to 140 ° C.

[022] In addition, the compounds according to the invention also make it possible to obtain maintenance of the rigidity of the composition at high temperatures, in particular for temperatures up to 150 ° C. In fact, the resin formed at from the compound and the aromatic polyphenol has improved temperature resistance compared to a resin formed from the aldehyde of formula A and the aromatic polyphenol. This temperature resistance can be determined by measuring the evolution of the rheometric torque as a function of time as described above. The aromatic polyphenol and the compound make it possible to obtain an extremely high torque value demonstrating an excellent maintenance of rigidity with increasing temperature.

[023] As already explained above, the inventors at the origin of the invention hypothesize that the compound is a precursor of the aldehyde of formula A. As already

- 5 explained above, this makes it possible to avoid immediate crosslinking of the resin due to a reaction which would generate, altered, the aldehyde function from the compound. Indeed, the reagents of formulas B and C would act as temporary protective reagents allowing, according to the inventors' hypothesis, the formation of each aldehyde function under predetermined reaction conditions (in other words the regeneration of the aldehyde of formula AT). The time taken to regenerate the aldehyde of formula A, even if very short, for example of the order of a minute, would allow better dispersion of the compound and of the aromatic polyphenol in the reaction mixture, which would make it possible to obtain a resin having more homogeneous crosslinking and therefore better temperature resistance of the resin.

Reagent B can therefore be a primary amine (alklyl and aryl radicals), a primary diamine (AL-NH ₂ , AR-NH ₂ radicals) or a diamine comprising a primary amine function and a secondary amine function. Reagent C can therefore be a secondary amine (alklyl and aryl radicals), a secondary diamine (AL-NR ₂ H and AR-NR ₂ H radicals) or a diamine comprising a primary amine function and a secondary amine function. Other embodiments of reagents B and C could also be envisaged while being in accordance with the invention defined above.

The invention also relates to a compound chosen from the group consisting of the compounds of the following formulas:

(l) (II) and mixtures of these compounds, in which:

- Ar represents an aromatic nucleus, optionally substituted,

- 7. ^ represents a monovalent radical chosen from the radicals of the following formulas:

-6HN-Rx

HN-Rx

R ₂ \

N-Rx

OH

Rx

Rx

Z ₂ represents a divalent radical of the following formula:

OH

OH in which:

to - the radical Ri represents a monovalent radical chosen from the group consisting of the alkyl, aryl, AL-NH ₂ radicals with AL representing a monovalent alkyl radical, AR-NH ₂ with AR representing a monovalent aryl radical, AL-NR ₂ H with AL representing a monovalent alkyl radical and AR-NR ₂ H with AR representing a monovalent aryl radical,

the radical R ₂ represents a monovalent hydrocarbon radical or a monovalent substituted hydrocarbon radical.

Unlike the above, the compound is defined here by its structure and not by its production process. The structures of the compound which plays the role of precursor of the aldehyde are those of the products obtained by reaction between the reagents of formulas A and B and / or C.

[027] The invention also relates to a process for the manufacture of a compound as defined above in which the reaction is carried out:

a reagent of formula A:

(A) a reagent of formula B and / or C:

H ₂ N (B)

(C) in which:

- Ar represents an aromatic nucleus, optionally substituted, the radical R! represents a monovalent radical chosen from the group consisting of alkyl, aryl, AL-NH ₂ radicals with AL representing a monovalent alkyl radical, AR-NH ₂ with AR representing a monovalent aryl radical, AL-NR ₂ H with AL representing a radical monovalent alkyl and AR-NR ₂ H with AR representing a monovalent aryl radical, the radical R ₂ represents a monovalent hydrocarbon radical or a monovalent substituted hydrocarbon radical.

[028] The invention also relates to the use of a compound as defined above for the manufacture of a resin for reinforcing a rubber composition.

[029] Preferably, the compound is used to generate a delay phase during the crosslinking of the resin, the resin being based on at least one aromatic polyphenol and at least the compound.

By the expression “resin based on”, it is understood of course to include a resin comprising the mixture and / or the product of the reaction between the various basic constituents used for this resin, preferably only the product of the reaction between the different basic constituents used for this resin, some of which may be intended to react or capable of reacting with each other or with their close chemical environment, at least in part, during the different phases of the process for manufacturing the composition, composites or tire, in particular during a baking step. Thus, it can also be provided that the aromatic polyphenol is derived from a precursor of this aromatic polyphenol.

[031] Thus, the invention makes it possible to manufacture a rubber composition comprising at least one resin based on at least one aromatic polyphenol and at least one compound according to the invention.

The invention also makes it possible to manufacture a rubber composition comprising at least one aromatic polyphenol and at least one compound according to the invention.

- 8 [033] The invention can also make it possible to implement a process for manufacturing a rubber composition, comprising a step of mixing at least one aromatic polyphenol and at least one compound according to the invention.

[034] Preferably, during the mixing step, at least one elastomer is also mixed with the composition.

[035] The invention can also make it possible to implement a process for manufacturing a rubber composition in the baked state, comprising:

a step of manufacturing a rubber composition in the raw state comprising a step of mixing at least one aromatic polyphenol and at least one compound according to the invention,

- then, a step of shaping the rubber composition in the raw state,

- Then, a crosslinking step, for example by vulcanization or curing, of the rubber composition during which a resin based on the aromatic polyphenol and on the compound according to the invention is crosslinked.

Preferably, during the mixing step, at least one elastomer is also mixed with the composition.

[037] As explained above, the inventors hypothesize that during the crosslinking step, for example by vulcanization or curing, we carry out, before the crosslinking of the resin:

a step of formation of the aldehyde from the compound or precursor of the aldehyde by formation, on the aromatic nucleus Ar, of at least one aldehyde function, and

- a step of crosslinking a phenol-aldehyde resin from the aromatic polyphenol and the aldehyde.

Thus, the use of the compound according to the invention also makes it possible to obtain rubber compositions having a rigidity at low deformation which is greatly improved compared to conventional rubber compositions.

By rubber composition is meant that the composition comprises at least one elastomer or a rubber (the two terms being synonymous) and at least one other component. A rubber composition therefore comprises an elastomer or rubber matrix in which at least the other component is dispersed. A rubber composition is in a plastic state in the raw state (non-crosslinked) and in an elastic state in the cooked state (crosslinked) but in no case in a liquid state. A rubber composition should not be confused with an elastomer latex which is a composition in a liquid state comprising a liquid solvent, generally water, and at least one elastomer or a rubber dispersed in the liquid solvent so as to form an emulsion. Thus, the rubber composition is not an aqueous adhesive composition.

- 9 [039] The rubber composition therefore comprises at least one (that is to say one or more) crosslinked reinforcing resin, this reinforcing resin being constituted by the resin; this resin being based on at least one (that is to say one or more) compound and at least one (that is to say one or more) aromatic polyphenol, constituents which will be described in detail below. -after.

In the present description, unless expressly indicated otherwise, all the percentages (%) indicated are percentages by weight. The acronym "pce" means parts by weight per hundred parts of elastomer.

[041] On the other hand, any range of values designated by the expression “between a and b” represents the range of values ranging from more than a to less than b (that is to say limits a and b excluded ) while any range of values designated by the expression “from a to b” signifies the range of values going from the bound “a” to the bound “b”, that is to say including the strict bounds “ a "and" b ".

[042] In the context of the invention, the carbon products mentioned in the description can be of fossil origin or bio-based. In the latter case, they can be, partially or totally, from biomass or obtained from renewable raw materials from biomass.

[043] Compound according to the invention [044] The aldehyde generated from the compound is very advantageous. Indeed, the Applicants have discovered during their research that such an aldehyde having an aromatic nucleus carrying an aldehyde function makes it possible to avoid the production of formaldehyde unlike conventional methylene donors. Indeed, the combination of phenolic resin conventionally used as a methylene acceptor with HMT or ΙΉ3Μ as a methylene donor in the prior art, produces formaldehyde during the vulcanization of the rubber composition . However, it is desirable to reduce or even eliminate formaldehyde from rubber compositions in the long term due to the environmental impact of these compounds and to recent regulatory developments, in particular European regulations, on this type of compound.

[045] In one embodiment, Ar is a six-membered aromatic nucleus.

[046] By link of a nucleus, we mean an atom constituting the skeleton of the nucleus. Thus, for example, a benzene nucleus comprises six links, each link consisting of a carbon atom. Thus the aromatic nucleus Ar comprises, as a link, carbon atoms and possibly one or more heteroatoms, in particular nitrogen, oxygen and sulfur atoms, possibly oxidized in the form of

- 10N-oxide or S-oxide.

[047] In a first variant of this embodiment of a six-membered aromatic ring, the rest of the aromatic ring Ar is unsubstituted. In other words, the aromatic nucleus carries a single group consisting of the -CHO function. For example, in this first variant, when the six-membered aromatic nucleus is a benzene nucleus, the aldehyde generated from the compound is benzaldehyde.

[048] In a second variant of this embodiment of a six-membered aromatic ring, the aromatic ring Ar is di-substituted.

[049] Preferably, in certain embodiments of this second variant, the reagent A has, for example, the following formula Aa:

[050] Such a preferred reagent of formula Aa makes it possible to obtain the compounds of the following formulas:

(Ilia) (IVa) (Va) [051] The compound is therefore preferably chosen from the group consisting of these compounds of formulas Ilia, IVa, Va and their mixtures.

[052] Advantageously, the two substituents of the aromatic ring Ar are in position para with respect to one another. By position para one with respect to the other, it will be understood that the targeted functions are opposite to each other, that is to say in positions 1 and 4 of the 6-membered aromatic nucleus . Similarly, the para position with respect to a function is a position opposite the function on the 6-membered aromatic nucleus carrying the function.

[053] Preferably, Ar is a benzene aromatic nucleus.

[054] In another embodiment, Ar is a five-membered aromatic nucleus.

[055] Analogously to the definition given above, by link of a nucleus, we mean an atom constituting the skeleton of the nucleus. Thus, for example, a furan nucleus comprises five links, four links each consisting of a carbon atom and the remaining link consisting of an oxygen atom. Thus the aromatic nucleus Ar comprises, as a link, carbon atoms and possibly one or more

-11 heteroatoms, in particular nitrogen, oxygen and sulfur atoms, possibly oxidized in the form of N-oxide or S-oxide.

[056] In a first variant of this embodiment of five-membered aromatic ring, the rest of the aromatic ring Ar is unsubstituted. In other words, the aromatic nucleus carries a single group consisting of the -CHO function.

[057] Preferably, in this first variant, the reagent of formula A has the following formula:

in which X comprises N, S or O, preferably X represents O.

[058] In this first variant, the aromatic nucleus Ar therefore has the following formula:

in which X comprises N, S or O, preferably X represents O.

[059] In a variant of the reagent of formula A, the reagent of formula A or aldehyde used is then furfuraldehyde of formula Ab1:

In another embodiment, X comprises N. Advantageously, X represents NH or NR ₄ with R ₄ representing a radical chosen from the group consisting of the monovalent radicals alkylene, arylene arylalkylene, alkylarylene, cycloalkylene and alkenylene.

[061] In another embodiment, X comprises S. Advantageously, X represents S, SR ₅ , SR5R5 ', S = O or O = S = O with R ₅ , R ₅ ' representing, independently one of l other, a radical chosen from the group consisting of the monovalent radicals alkylene, arylene arylalkylene, alkylarylene, cycloalkylene and alkenylene.

In a second variant of this embodiment of a five-membered aromatic ring, the rest of the aromatic ring Ar is di-substituted.

[063] Preferably, in certain embodiments of this second variant, the reagent A has, for example, the formula Aa ’as follows:

[064] Such a preferred reagent of formula Aa 'makes it possible to obtain the compounds of the following formulas:

(IIIb) (IVb) (Vb) [065] The compound is therefore preferably chosen from the group consisting of these compounds of formulas IIIb, IVb, Vb and their mixtures.

[066] Preferably, in this second variant, the reagent of formula A has the following formula Ac:

o

(Ac) in which X comprises N, S or O, preferably X represents O.

[067] In this second variant, the aromatic nucleus Ar therefore preferably has the following formula:

in which X comprises N, S or O, preferably X represents O.

[068] Even more preferably, the reagent of formula A has the following formula Ad:

in which X comprises N, S or O, preferably X represents O.

[069] In this second variant, the two substituents of the aromatic nucleus Ar are therefore even more preferably in position 2 and 5 relative to one another.

- X [070] When X represents O, the reagent of formula Ad is 2,5-furanedicarboxaldehyde. [071] Thus, more preferably, the reagent of formula A is chosen from the group consisting of 1,4-benzene-dicarboxaldehyde, furfuraldehyde, 2,5furanedicarboxaldehyde and mixtures of these reagents. Preferably, when the resin is based on at least one polyphenol and at least one compound according to the invention, the composition is devoid of formaldehyde.

[072] When the resin is based on at least one polyphenol, at least one compound according to the invention and aldehydes, each aldehyde is preferably different from formaldehyde. The composition is then also devoid of formaldehyde.

In other words and preferably, when an aldehyde is present, the or each aldehyde of the resin is different from formaldehyde.

By free of formaldehyde, it is meant that the mass content of formaldehyde by total weight of the aldehyde (s) is less than or equal to 10%, preferably 5% and more preferably 2%, these percentages corresponding to traces likely to be present in the aldehyde (s) used industrially.

Preferably, the radical represents a monovalent radical chosen from the group consisting of AL-NH ₂ radicals with AL representing a monovalent alkyl radical, AR-NH ₂ with AR representing a monovalent aryl radical, AL-NR ₂ H with AL representing a monovalent alkyl radical and AR-NR ₂ H with AR representing a monovalent aryl radical. The use of a primary or secondary diamine makes it possible, during the regeneration of the aldehyde from the compound, to generate a diamine in the rubber composition which can be used as a molecule reactive with respect to other molecules present in the composition, for example with respect to the molecules involved in the vulcanization reaction in order to accelerate the start of vulcanization.

[076] More preferably, the monovalent alkyl AL radical is a linear alkyl radical comprising a number of carbon atoms ranging from 1 to 15, preferably from 2 to 12 and more preferably from 2 to 8.

Advantageously, the radical R ₂ represents a monovalent radical chosen from the group consisting of the alkyl, aryl, arylalkyl, alkylaryl, cycloalkyl and alkenyl radicals.

Advantageously, each radical R ^ R ₂ is devoid of reactive function vis-à-vis an aromatic polyphenol. By reactive function is meant here a function which would react under reaction conditions necessary for the regeneration of the aldehyde of formula A and under reaction conditions necessary for the crosslinking of the resin. Very preferably, each radical R ^ R ₂ is therefore, for example, devoid of aldehyde and hydroxymethyl function.

- 14 [079] Aromatic polyphenol [080] By aromatic polyphenol is meant a molecule comprising at least one aromatic nucleus and at least two hydroxyl functions carried by the aromatic nucleus (s).

[081] Preferably, the aromatic polyphenol comprises an aromatic nucleus carrying at least two hydroxyl functions. More preferably, the aromatic polyphenol comprises an aromatic ring carrying at least two hydroxyl functions in meta position relative to each other, the two ortho positions of at least one of the hydroxyl functions being unsubstituted.

[082] The aromatic polyphenol can therefore be, in one embodiment, a simple molecule comprising one or more aromatic rings, at least one of these aromatic rings, or even each aromatic ring carrying at least two hydroxyl functions in the meta position one with respect to the other, the two ortho positions of at least one of the hydroxyl functions being unsubstituted. Such a simple molecule does not include a repeating unit.

[083] The aromatic polyphenol can be, in another embodiment, a pre-condensed resin based:

- At least one aromatic polyphenol, comprising at least one aromatic ring carrying at least two hydroxyl functions in meta position relative to each other, the two ortho positions of at least one of the hydroxyl functions being non substituted; and

- At least one compound comprising an aldehyde function, for example an aromatic aldehyde carrying at least one aldehyde function, comprising at least one aromatic nucleus but alternatively a non-aromatic aldehyde, for example formaldehyde.

[084] Such a pre-condensed resin based on aromatic polyphenol comprises, unlike the simple molecule described above, a repeating unit. In this case, the repeating unit comprises at least one aromatic nucleus carrying at least two hydroxyl functions in meta position relative to one another.

[085] In another embodiment, the aromatic polyphenol is a mixture of an aromatic polyphenol forming a single molecule and a pre-condensed resin based on aromatic polyphenol.

In the particular embodiments which follow, the aromatic nucleus (s) of the aromatic polyphenol are described. For the sake of clarity, it describes the "aromatic polyphenol" in its form of simple molecule. This aromatic polyphenol can then be condensed and will partially define the repeating pattern. The characteristics of the precondensed resin are described in more detail below.

- 15 [087] By meta position relative to one another, it will be understood that the hydroxyl functions are carried by carbons of the aromatic nucleus separated from each other by a single other carbon of the aromatic nucleus.

[088] By the ortho position of a group, we mean the position occupied by the carbon of the aromatic nucleus immediately adjacent to the carbon of the aromatic nucleus carrying the group.

[089] In a preferred embodiment, the aromatic nucleus of the aromatic polyphenol carries three hydroxyl functions in the meta position relative to each other. [090] Preferably, the two ortho positions of each hydroxyl function of the aromatic polyphenol are unsubstituted. By this is meant that the two carbon atoms located on either side (in the ortho position) of the carbon atom carrying the group -O-H are carriers of a single hydrogen atom.

[091] Even more preferably, the remainder of the aromatic nucleus of the aromatic polyphenol is unsubstituted. By this is meant that the other carbon atoms of the rest of the aromatic nucleus (those other than the carbon atoms carrying the -O-H groups) carry a simple hydrogen atom.

[092] In one embodiment, the aromatic polyphenol comprises several aromatic rings, at least two of them each carrying at least two hydroxyl functions in meta position relative to each other, the two positions ortho of at least one of the hydroxyl functions of at least one aromatic ring being unsubstituted.

[093] In a preferred embodiment, at least one of the aromatic rings of the aromatic polyphenol carries three hydroxyl functions in the meta position relative to each other.

[094] Preferably, the two ortho positions of each hydroxyl function of at least one aromatic ring are unsubstituted.

[095] Even more preferably, the two ortho positions of each hydroxyl function of each aromatic ring are unsubstituted.

[096] Even more preferably, the remainder of each of the aromatic rings is unsubstituted. By this is meant that the other carbon atoms of the rest of each aromatic nucleus (those other than carbon atoms carrying the hydroxyl functions or carrying the group linking the aromatic nuclei together) are carrying a single hydrogen atom.

[097] Advantageously, the or each aromatic nucleus of the aromatic polyphenol is a benzene nucleus.

[098] By way of example of an aromatic polyphenol comprising a single aromatic ring, mention may be made in particular of resorcinol and phloroglucinol, of respective formulas 10 and

By way of examples, in the case where the aromatic polyphenol comprises several aromatic rings, at least two of these aromatic rings, identical or different, are chosen from those of general formulas:

(12-a) (12-b) (12-c) (12-d) in which the symbols T, T ₂ , identical or different if they are several on the same aromatic ring, represent an atom (for example carbon , sulfur or oxygen) or a linking group by definition at least divalent, which links at least these two aromatic rings to the rest of the aromatic polyphenol.

Another example of an aromatic polyphenol is 2,2 ', 4,4'-tetrahydroxydiphenyl sulfide, having the following formula:

Another example of an aromatic polyphenol is 2,2 ', 4,4'-tetrahydroxydiphenyl benzophenone, of the following formula:

It is noted that each compound 13 and 14 is an aromatic polyphenol comprising two aromatic rings (of formulas 12-c) each of which carries at least two (in this case two) -OH groups in the meta l position one over the other.

It is noted that in the case of an aromatic polyphenol comprising at least one aromatic ring in accordance with the formula 12-b, the two ortho positions of each -O-H group of at least one aromatic ring are unsubstituted. In the case of an aromatic polyphenol comprising several aromatic rings conforming to formula 12-b, the two ortho positions of each -O-H group of each aromatic ring are unsubstituted. Advantageously, the aromatic polyphenol is chosen from the group consisting of resorcinol, phloroglucinol, 2,2 ', 4,4'-tetrahydroxydiphenyl sulfide, 2,2', 4,4tetrahydroxybenzophenone, pre-condensed resins from at least one of these polyphenols and mixtures of these aromatic polyphenols.

According to one embodiment of the invention, the aromatic polyphenol is chosen from the group consisting of resorcinol 10, phloroglucinol 11, 2,2 ', 4,4'-tetrahydroxydiphenyl sulfide 13, 2,2 ', 4,4-tetrahydroxybenzophenone 14 and mixtures of these aromatic polyphenols. In a particularly advantageous embodiment, the aromatic polyphenol is phloroglucinol 11.

In one embodiment, the aromatic polyphenol comprises a precondensed resin based on the aromatic polyphenol as described in any one of these embodiments.

This pre-condensed resin is advantageously based:

- at least one aromatic polyphenol as defined above, and preferably chosen from the group consisting of resorcinol 10, phloroglucinol 11, 2,2 ', 4,4'-tetrahydroxydiphenyl sulfide 13, 2,2', 4,4tetrahydroxybenzophenone 14, and mixtures thereof; and

- At least one compound comprising an aldehyde function, and preferably an aromatic aldehyde carrying at least one aldehyde function, comprising at least one aromatic nucleus.

Advantageously, the compound comprising an aldehyde function is chosen from the group consisting of formaldehyde, benzaldehyde, furfuraldehyde, 2,53054230

- 18furanedicarboxaldehyde, 1,4-benzenedicarboxaldehyde, 1,3-benzenedicarboxaldehyde, 1,2-benzenedicarboxaldehyde and mixtures of these compounds. Very advantageously, the compound comprising an aldehyde function is chosen from the group consisting of furfuraldehyde, 2,5-furanedicarboxaldehyde, 1,4-benzenedicarboxaldehyde, 1,3benzenedicarboxaldehyde, 1,2-benzenedicarboxaldehyde and mixtures of these compounds .

Thus, in the pre-condensed resin based on aromatic polyphenol, the repeating unit meets the characteristics of the aromatic polyphenol defined above except that at least one of the carbon atoms of the aromatic ring, which was unsubstituted, is connected to another motif.

Whatever the compound other than the aromatic polyphenol at the base of the pre-condensed resin, this pre-condensed resin is free of free formaldehyde. Indeed, even in the case where the pre-condensed resin is based on an aromatic polyphenol as described above and on formaldehyde, the formaldehyde having already reacted with the aromatic polyphenol, the pre-condensed resin is devoid of free formaldehyde capable to be able to react with the aromatic polyphenol according to the invention in a subsequent step.

The aromatic polyphenol can also comprise a mixture of a free molecule of aromatic polyphenol and of a pre-condensed resin based on aromatic polyphenol, as described above. In particular, the aromatic polyphenol may also comprise a mixture of phloroglucinol and a pre-condensed resin based on phloroglucinol.

Rubber compositions [0113] Depending on the use of the composition, an amount of compound ranging from 0.1 to 25 phr will be used. Likewise, an amount of aromatic polyphenol derivative ranging from 0.1 to 25 phr will be used.

According to the use that is made of the composition, the rubber composition has, in the baked state, a secant module with 10% elongation MA10 measured according to standard ASTM D 412 of 1998 (test piece C ) greater than or equal to 10 MPa, preferably 20 MPa, preferably 30 MPa, more preferably 40 MPa and even more preferably 60 MPa.

Preferably, the rubber composition comprises a diene elastomer. By elastomer or rubber (the two terms being synonyms) of the diene type, we generally mean an elastomer derived at least in part (i.e. a homopolymer or a copolymer) from diene monomers (monomers carrying two

- 19 double carbon-carbon bonds, conjugated or not).

In a particularly preferred manner, the diene elastomer of the rubber composition is chosen from the group consisting of polybutadienes (BR), synthetic polyisoprenes (IR), natural rubber (NR), butadiene copolymers, isoprene copolymers and mixtures of these elastomers. Such copolymers are more preferably chosen from the group consisting of butadiene styrene copolymers (SBR), isoprene-butadiene copolymers (BIR), isoprene styrene copolymers (SIR), isoprene-butadiene-styrene copolymers ( SBIR) and mixtures of such copolymers.

The rubber compositions can contain a single diene elastomer or a mixture of several diene elastomers, the diene elastomer or elastomers which can be used in combination with any type of synthetic elastomer other than diene, or even with polymers other than elastomers , for example thermoplastic polymers.

Preferably, the rubber composition comprises a reinforcing filler. When a reinforcing filler is used, one can use any type of reinforcing filler known for its capacity to reinforce a rubber composition which can be used for the manufacture of tires, for example an organic filler such as carbon black, a filler reinforcing inorganic such as silica, or a blend of these two types of filler, in particular a blend of carbon black and silica.

As carbon blacks, all the carbon blacks conventionally used in tires (so-called pneumatic blacks) are suitable. For example, mention will be made more particularly of reinforcing carbon blacks of the 100, 200 or 300 series (ASTM grades).

In the case of using carbon blacks with an isoprene elastomer, the carbon blacks could, for example, already be incorporated into the isoprene elastomer in the form of a masterbatch (see for example applications WO 97/36724 or WO 99/16600).

As examples of organic fillers other than carbon blacks, mention may be made of organic fillers of functionalized polyvinylaromatic as described in applications WO-A-2006/069792 and WO-A-2006/069793.

By reinforcing inorganic filler, should be understood in the present application, by definition, any inorganic or mineral filler (whatever its color and its origin (natural or synthetic), also called white filler, clear filler or even non filler black (non-black filler) as opposed to carbon black, capable of reinforcing on its own, without other means than an intermediate coupling agent, a

Rubber composition intended for the manufacture of tires, in other words capable of replacing, in its reinforcement function, a conventional carbon black of pneumatic grade. Such a charge is generally characterized, in a known manner, by the presence of hydroxyl groups (-OH) on its surface.

The physical state in which the reinforcing inorganic charge occurs is indifferent, whether in the form of powder, microbeads, granules, beads or any other suitable densified form. Of course, the term reinforcing inorganic filler is also understood to mean mixtures of different reinforcing inorganic fillers, in particular highly dispersible siliceous and / or aluminous fillers as described below.

As reinforcing inorganic fillers, mineral fillers of the siliceous type, in particular silica (SiO ₂ ), or of the aluminous type, in particular of alumina (AI ₂ O ₃ ), are suitable. The silica used can be any reinforcing silica known to a person skilled in the art, in particular any precipitated or pyrogenic silica having a BET surface as well as a CTAB specific surface both less than 450 m2 / g, preferably from 30 to 400 m2 / g. As highly dispersible precipitated silicas (known as HDS), mention may be made, for example, of the Ultrasil 7000 and Ultrasil 7005 silicas from the company Evonik, the Zeosil 1165MP, 1135MP and 1115MP silicas from the company Rhodia, the Hi-Sil EZ150G silica from the company PPG, Zeopol silicas 8715, 8745 and 8755 from the company Huber, silicas with a high specific surface as described in application WO 03/16837.

Finally, those skilled in the art will understand that, as an equivalent charge of the reinforcing inorganic charge described in this paragraph, a reinforcing charge of another nature, in particular organic, could be used, since this reinforcing charge would be covered with an inorganic layer such as silica, or would have on its surface functional sites, in particular hydroxyl, requiring the use of a coupling agent to establish the connection between the filler and the elastomer.

Preferably, the rate of total reinforcing filler (carbon black and / or reinforcing inorganic filler such as silica) is included in a range from 5 to 120 phr, more preferably from 5 to 100 phr and even more preferably from 5 at 90 pce.

Carbon black can advantageously constitute the only reinforcing filler or the majority reinforcing filler. Of course, it is possible to use a single carbon black or a blend of several carbon blacks of different ASTM grades. Carbon black can also be used in blending with other reinforcing fillers and in particular reinforcing inorganic fillers as described above, and in particular silica.

When an inorganic filler (for example silica) is used in the

- 21 rubber composition, alone or in a blend with carbon black, its rate is within a range of 0 to 70 phr, preferably from 0 to 50 phr, in particular also from 5 to 70 phr, and even more preferably this proportion varies from 5 to 50 pc, particularly from 5 to 40 pc.

Preferably, the rubber composition comprises various additives.

The rubber compositions can also comprise all or part of the usual additives usually used in elastomer compositions intended for the manufacture of tires, such as for example plasticizers or extension oils, whether the latter are of aromatic nature or non-aromatic, pigments, protective agents such as anti-ozone waxes, anti-ozone chemicals, anti-oxidants, anti-fatigue agents or even adhesion promoters.

Preferably, the rubber composition comprises a crosslinking system, more preferably of vulcanization.

The vulcanization system comprises a sulfur donor agent, for example sulfur.

Preferably, the vulcanization system comprises vulcanization activators such as zinc oxide and stearic acid.

Preferably, the vulcanization system comprises a vulcanization accelerator and / or a vulcanization retarder.

The sulfur or sulfur donor agent is used at a preferential rate comprised within a range of 0.5 to 10 phr, more preferably comprised within a range of 0.5 to 8.0 phr. All the accelerators, retarders and vulcanization activators are used at a preferential rate within a range of 0.5 to 15 phr. The vulcanization activator (s) is or are used at a preferential rate comprised within a range of 0.5 and 12 phr.

The actual crosslinking system is preferably based on sulfur and a primary vulcanization accelerator, in particular an accelerator of the sulfenamide type. In addition to this vulcanization system, various secondary accelerators or known vulcanization activators such as zinc oxide, stearic acid, guanidine derivatives (in particular diphenylguanidine), etc.

One can use as accelerator (primary or secondary) any compound capable of acting as an accelerator for vulcanization of diene elastomers in the presence of sulfur, in particular accelerators of the thiazole type as well as their derivatives, accelerators of the thiuram type, and zinc dithiocarbamate type. These accelerators are more preferably chosen from the group consisting of 2mercaptobenzothiazyl disulfide (abbreviated to MBTS), N-cyclohexyl-2-benzothiazyl sulfenamide (in

-22 abbreviated CBS), Ν, Ν-dicyclohexyl- 2-benzothiazyle sulfenamide (abbreviated DCBS), N-terbutyl-2-benzothiazyle sulfenamide (abbreviated TBBS), N-ter-butyl-2-benzothiazyl sulfenimide (abbreviated TBSI) , zinc dibenzyldithiocarbamate (abbreviated as ZBEC) and mixtures of these compounds. Preferably, a primary accelerator of the sulfenamide type is used.

In one embodiment, the rubber composition is in the cooked state, that is to say vulcanized. In other embodiments, the composition is in the raw state, that is to say unvulcanized, the crosslinked resin having been added subsequently to the unvulcanized composition.

In certain embodiments, the composition comprises a residue obtained from the radical 7. ^ and / or Z ₂ . Prior to crosslinking of the resin, and as assumed by the inventors at the origin of the invention, after formation of the aldehyde function, each radical and / or Z ₂ may make it possible to obtain a residue generated in situ. Certain residues remain definitively in the composition and, if necessary, can be used for some of their properties.

In other embodiments, the residue generated remains only temporarily in the composition, either because it leaves it spontaneously under the conditions of manufacture of the composition, for example in the form of gas, in particular in the case where the residue is volatile, either because an optional step of extracting this residue is used in the process for manufacturing the composition.

In one embodiment, the phenol aldehyde resin not yet having crosslinked, the rubber composition comprises:

at least one aromatic polyphenol comprising at least one aromatic ring carrying at least two hydroxyl functions in meta position relative to each other, the two ortho positions of at least one of the hydroxyl functions being unsubstituted, and

- at least one compound resulting from the reaction between a reagent of formula A:

(A) and a reagent of formula B and / or C

H ₂ NR-, (B)

(C) and mixtures of these compounds, in which:

-23- Ar represents an aromatic ring, optionally substituted,

- the radical R! represents a monovalent radical chosen from the group consisting of alkyl, aryl, AL-NH ₂ radicals with AL representing a monovalent alkyl radical, AR-NH ₂ with AR representing a monovalent aryl radical, AL-NR ₂ H with AL representing a radical monovalent alkyl and AR-NR ₂ H with AR representing a monovalent aryl radical,

the radical R ₂ represents a monovalent hydrocarbon radical or a monovalent substituted hydrocarbon radical.

In this embodiment, the compound resulting from the reaction between the reagents A and B 10 and / or C is chosen from the group consisting of the compounds of the following formulas:

(l) (II) and mixtures of these compounds, in which:

- Ar represents an aromatic nucleus, optionally substituted,

- Ζί represents a monovalent radical chosen from the radicals of the following formulas:

HN-R-i

HN-R-i

R ₂ \

N-R-i OH

Ri

Ri

Z ₂ represents a divalent radical of the following formula:

-24OH

N-Ri

OH in which:

- the radical R! represents a monovalent radical chosen from the group consisting of alkyl, aryl, AL-NH ₂ radicals with AL representing a monovalent alkyl radical, AR-NH ₂ with AR representing a monovalent aryl radical, AL-NR ₂ H with AL representing a radical monovalent alkyl and AR-NR ₂ H with AR representing a monovalent aryl radical,

the radical R ₂ represents a monovalent hydrocarbon radical or a monovalent substituted hydrocarbon radical.

[0145] Preferably, in this embodiment, the composition is in the raw state, that is to say unvulcanized.

[0146] Preferably, the rubber composition can be used in the tire in the form of a layer. By layer is meant any three-dimensional element, of any shape and thickness, in particular in sheet, strip or other element of any cross section, for example rectangular or triangular.

Rubber composite [0148] A rubber composite is reinforced with at least one reinforcing element embedded in the rubber composition comprising a resin based on at least one aromatic polyphenol and at least one compound according to l 'invention.

This rubber composite can be prepared according to a process comprising at least the following steps:

in a first step, combining at least one reinforcing element with a rubber composition (or elastomer, the two terms are synonymous) to form a rubber composite reinforced with the reinforcing element; then, during a second step, crosslink by baking, for example by vulcanization, preferably under pressure, the composite thus formed.

Among the reinforcing elements, mention may be made of textile, metallic or hybrid textile-metal reinforcing elements.

By textile is meant, in a manner well known to those skilled in the art, any material other than metallic, whether natural or synthetic, capable of being transformed into yarn or fiber by any process. appropriate transformation. Mention may be made, for example, without the examples below being limiting, of a polymer spinning process such as for example melt spinning, solution spinning or gel spinning.

This textile material can consist of a thread or fiber or also a fabric made from threads or fibers, for example a woven fabric with warp threads and weft threads, or a crossover fabric with crossed sons.

Preferably, this textile material of the invention is chosen from the group consisting of monofilaments (or unitary threads), multifilament fibers, assemblies of such threads or fibers, and mixtures of such materials. It is more particularly a monofilament, a multifilament fiber or a twist.

By wire or fiber is generally meant any elongated element of great length relative to its cross section, whatever the shape of the latter, for example circular, oblong, rectangular or square, or even flat, this wire can be straight as non-straight, for example twisted, or wavy. The largest dimension of its cross section is preferably less than 5 mm, more preferably less than 3 mm.

This wire or this fiber can take any known form, it can for example be an elementary monofilament of large diameter (for example and preferably equal to or greater than 50 μm), a multifilament fiber (constituted of a plurality of elementary filaments of small diameter, typically less than 30 μm), of a plied or textile cord formed of several textile fibers or monofilaments twisted or cabled together, or of an assembly, a group, a row of yarns or fibers such as for example a strip or strip comprising several of these monofilaments, fibers, twists or cords grouped together, for example aligned in a main direction, straight or not. The textile materials can be made of organic or polymeric material, such as inorganic material.

Examples of inorganic materials include glass, carbon.

The invention is preferably implemented with materials of polymeric material, of the thermoplastic as well as non-thermoplastic type.

Examples of polymeric materials of the non-thermoplastic type include, for example, aramid (aromatic polyamide) and cellulose, natural as well as artificial, such as cotton, rayon, linen, hemp.

As examples of polymeric materials of the thermoplastic type, there will preferably be mentioned aliphatic polyamides and polyesters. Among the polyamides

-26aliphatics, mention may especially be made of polyamides 4-6, 6, 6-6, 11 or 12. Among the polyesters, mention may, for example, be made of PET (polyethylene terephthalate), PEN (polyethylene naphthalate), PBT (polybutylene terephthalate) , PBN (polybutylene naphthalate), PPT (polypropylene terephthalate), PPN (polypropylene naphthalate).

By metallic, by definition is meant one or more wire elements made up predominantly (that is to say for more than 50% of its mass) or entirely (for 100% of its mass) of a metallic material. Preferably, the metallic material is steel, more preferably perlitic (or ferrito-perlitic) carbon steel advantageously comprising between 0.4% and 1.2% by mass of carbon.

The metallic reinforcing element can be a monofilament, a cable comprising several metallic monofilaments or a multi-strand cable comprising several cables then called strands.

In the preferred case where the reinforcing element comprises several metallic monofilaments or several strands, the metallic monofilaments or the strands are assembled by twisting or by wiring. Remember that there are two possible assembly techniques:

either by twisting: the metallic monofilaments or the strands undergo both a collective twist and an individual twist around their own axis, which generates a couple of twists on each of the monofilaments or strands;

either by wiring: the metallic monofilaments or the strands undergo only a collective twist and do not undergo an individual twist around their own axis.

Optionally, the reinforcing element comprises several monofilaments and is of the type erased in situ, that is to say that the reinforcing element is erased from the inside, during its manufacture even by an eraser filling. Such metallic wire elements are known to those skilled in the art. The composition of the filling rubber may or may not be identical to the rubber composition in which the reinforcing element is embedded.

Tires [0166] Such tires are for example those intended to equip motor vehicles of the tourism type, SUV (Sport Utility Vehicles), two wheels (in particular bicycles, motorcycles), airplanes, as industrial vehicles chosen from vans , Heavy goods vehicle, i.e. metro, bus, road transport equipment (trucks, tractors, trailers), off-road vehicles such as agricultural or civil engineering equipment, other transport or handling.

By way of example, the appended FIG. 1 very schematically represents (without

-27respect of a specific scale), a radial section of a tire in accordance with the invention for a truck-type vehicle.

This tire 1 comprises a crown 2 reinforced by a crown reinforcement or belt 6, two sidewalls 3 and two beads 4, each of these beads 4 being reinforced with a bead wire. The crown 2 is surmounted by a strip of bearing not shown in this schematic figure. A carcass reinforcement 7 is wound around the two rods 5 in each bead 4, the reversal 8 of this reinforcement 7 being for example disposed towards the outside of the tire 1 which is here shown mounted on its rim 9. The carcass reinforcement 7 is in a manner known per se consisting of at least one ply reinforced by so-called radial cables, for example metallic, that is to say that these cables are arranged practically parallel to one another and extend from one bead to the other so as to form an angle between 80 ° and 90 ° with the median circumferential plane (plane perpendicular to the axis of rotation of the tire which is located midway between the two beads 4 and passes through the middle of the crown reinforcement 6).

This tire 1 of the invention has for example the characteristic that at least one crown reinforcement 6 and / or its carcass reinforcement 7 comprises a rubber composition comprising a resin based on at least one aromatic polyphenol and at least one compound according to the invention.

[0170] Process for manufacturing the compound according to the invention [0171] The reaction between the reagent of formula A and the reagent of formula B and / or C is carried out in a polar solvent. Preferably, the solvent is chosen from the group consisting of tetrahydrofuran, ether and water and more preferably the solvent is water. Water is particularly advantageous because on the one hand, it is non-reactive with respect to reagents A, B and C and makes it possible to dissolve these reagents and, on the other hand, allows the compound to be easily extracted according to the invention which is not or very sparingly soluble therein. In addition, by carrying out the reaction in water in which the compound according to the invention is not or very sparingly soluble, it precipitates therein and therefore cannot be hydrolyzed to give the starting reagents A, B and / or C .

In one embodiment, the reaction is carried out with a molar excess of reagent B and / or C relative to reagent A. By molar excess is meant that once the reaction has been carried out, there remains at least 10% the initial molar amount of reagent B and / or C in the reaction medium.

In one embodiment in which the compound precipitates from the reaction medium, in order to wash the compound according to the invention, the compound is washed with water, preferably with water having a temperature above Room temperature.

-28We will use a temperature high enough to promote the solubilization of any excess of reagent B and / or C and other impurities, for example at a temperature above 50 ° C.

Method of manufacturing the rubber composition The manufacturing method described above and below makes it possible to manufacture the rubber composition comprising a resin based on at least one aromatic polyphenol and at least one compound according to the invention ..

The rubber composition can be manufactured in suitable mixers, using two successive preparation phases well known to those skilled in the art:

a first working phase or thermomechanical kneading (so-called nonproductive phase) at high temperature, up to a maximum temperature between 110 ° C and 190 ° C, preferably between 130 ° C and 180 ° C, followed by a second phase mechanical work (so-called productive phase) up to a lower temperature, typically below 110 ° C, for example between 40 ° C and 100 ° C, finishing phase during which the crosslinking system is incorporated.

In one embodiment, the method comprises the following steps:

- incorporating into an elastomer, during a first step, a reinforcing filler, by thermomechanically kneading the whole, until a maximum temperature of between 110 ° C and 190 ° C is reached;

- cool the assembly to a temperature below 110 ° C;

- Then incorporate, during a second step, a crosslinking system, the aromatic polyphenol and the compound according to the invention;

- mix everything at a temperature below 110 ° C.

For example, the non-productive phase is carried out in a single thermomechanical step during which all the necessary basic constituents are introduced into a suitable mixer such as a usual internal mixer. (diene elastomer, reinforcing filler, etc.), then in a second step, for example after one to two minutes of kneading, the other additives, possible agents for covering the filler or additional processing, with the exception of the crosslinking system, of the aromatic polyphenol and of the compound according to the invention. The total duration of the kneading, in this non-productive phase, is preferably between 1 and 15 min.

After cooling the mixture thus obtained, it is then incorporated into an external mixer such as a roller mixer, kept at low temperature (by

-29 example between 40 ° C and 100 ° C), the crosslinking system, the compound according to the invention and the aromatic polyphenol. The whole is then mixed (productive phase) for a few minutes, for example between 2 and 15 min.

The composition thus obtained in the raw state can then be shaped, for example calendered, for example in the form of a sheet, a plate in particular for characterization in the laboratory, or even extruded, for example to form a rubber profile used for the manufacture of a tire.

Then, after a possible step of assembling together several compositions formed in the form of plies or strips in the form of a composite or a raw tire blank, a crosslinking step is carried out, by example a vulcanization step of the composition, the composite or the blank during which the resin based on the aromatic polyphenol and the compound is crosslinked. The crosslinking step, here of vulcanization, is carried out at a temperature greater than or equal to 120 ° C., preferably greater than or equal to 140 ° C. The composition is obtained in the cooked state.

In another embodiment, the method comprises the following steps:

- incorporating into an elastomer, during a first step, a filler reinforcing the aromatic polyphenol and the compound according to the invention, by thermomechanically kneading the whole, until a maximum temperature of between 110 ° C. and 190 ° C. is reached ;

- cool the assembly to a temperature below 110 ° C;

- then incorporate, during a second step, a crosslinking system;

- mix everything at a temperature below 110 ° C.

The invention and its advantages will be easily understood in the light of the following exemplary embodiments.

Examples of carrying out the invention and comparative tests [0185] These tests demonstrate that:

- The rigidity of the rubber composition comprising a resin based on a compound according to the invention is greatly increased compared to a rubber composition devoid of reinforcing resin;

- the rigidity of the rubber composition is maintained at high temperatures, in particular for temperatures up to 150 ° C.

- There is a delay phase during the crosslinking of the resin based on a compound according to the invention making it possible to avoid early crosslinking of the resin with respect to a phenol-aldehyde resin crosslinked directly from the aromatic polyphenol and from the corresponding aldehyde (the aldehyde of formula A);

- the resin based on a compound according to the invention is devoid of formaldehyde and does not

- 30 does not generate during its formation.

For this, several rubber compositions, noted below T0, T1 and 11 were prepared as indicated above and are collated in Table 1 appended below.

All the compositions T0, T1 and 11 have a common part in their formulations (expressed in phr, parts by weight per hundred parts of elastomer): 100 phr of natural rubber, 75 phr of carbon black N326, 1, 5 pce of N-1, 3-dimethylbutyl-N-phenyl-paraphenylenediamine, 1.5 pce of stearic acid, 5 pce of ZnO, 1 pce of N-tertiarybutyl-2benzothiazole sulfonamide and 7 pce of insoluble sulfur 20H.

The composition T0 does not include any reinforcing resin added to this common part.

In addition to the common part, the composition T1 comprises a phenolaldehyde resin based on phloroglucinol and 1,4-benzene-dicarboxaldehyde. Composition T1 comprises 14 phr of phloroglucinol and 14 phr of 1,4-benzene-dicarboxaldehyde.

In addition to the common part, composition 11 comprises an aromatic polyphenol and a compound forming a precursor of an aromatic aldehyde, indicated in table 1 in molar proportions 1 (aromatic polyphenol) / 1 (compound), and with 14 pce of aromatic polyphenol.

The compound according to the invention of composition 11 is derived from the reaction between a reagent of formula A:

(A) and a reagent of formula B and / or C:

H ₂ N (B)

(C) in which:

- Ar represents an aromatic nucleus, optionally substituted, the radical R! represents a monovalent radical chosen from the group consisting of alkyl, aryl, AL-NH ₂ radicals with AL representing a monovalent alkyl radical, AR-NH ₂ with AR representing a monovalent aryl radical, AL-NR ₂ H with AL representing a radical monovalent alkyl and AR-NR ₂ H with AR representing a monovalent aryl radical,

- 31 the radical R ₂ represents a monovalent hydrocarbon radical or a monovalent substituted hydrocarbon radical.

As explained above, the compound of composition 11 resulting from the reaction between the reagents of formulas A and B and / or C is chosen from the group consisting of the compounds of the following formulas:

Z ₂ (l) (II) and mixtures of these compounds, in which:

- Ar represents an aromatic nucleus, optionally substituted,

- 7. ^ represents a monovalent radical chosen from the radicals of the following formulas:

HN-R-i

HN-R-i

R ₂ \

N-R-,

OH

Ri

Ri

- Z ₂ represents a divalent radical of the following formula:

OH

OH

- 32 in which:

- the radical R! represents a monovalent radical chosen from the group consisting of alkyl, aryl, AL-NH ₂ radicals with AL representing a monovalent alkyl radical, AR-NH ₂ with AR representing a monovalent aryl radical, AL-NR ₂ H with AL representing a radical monovalent alkyl and AR-NR ₂ H with AR representing a monovalent aryl radical,

the radical R ₂ represents a monovalent hydrocarbon radical or a monovalent substituted hydrocarbon radical.

Aromatic polyphenol of composition 11 [0194] The aromatic polyphenol of rubber composition 11 is chosen from the group consisting of resorcinol, phloroglucinol, 2,2 ', 4,4'-tetrahydroxydiphenyl sulfide, 2 , 2 ', 4,4'-tetrahydroxybenzophenone, pre-condensed resins from at least one of these polyphenols and mixtures of these aromatic polyphenols. The aromatic polyphenol of composition 11 comprises a single aromatic nucleus, here benzene, carrying three, and only three, -O-H groups in the meta position relative to each other. The remainder of the aromatic ring of the aromatic polyphenol is unsubstituted. In particular, the two ortho positions of each -O-H group are unsubstituted. The aromatic polyphenol of composition 11 is phloroglucinol.

Compound C1 precursor of the aldehyde of composition 11 [0196] Compound C1 is obtained from the reaction using a reagent of formula Aa below:

in which Ar is a di-substituted six-membered aromatic ring, in this case a benzenic ring carrying two -CHO functions. Here the two -CHO functions are in positions by one relative to the other. The reagent of formula Aa is 1,4-benzenedicarboxaldehyde.

The other reagent reacting with the reagent of formula Aa is a reagent of formula B: H ₂ NR!

in which R! represents a monovalent radical chosen from the group consisting of alkyl, aryl, AL-NH ₂ radicals with AL representing a monovalent alkyl radical, AR-NH ₂ with AR representing a monovalent aryl radical, AL-NR ₂ H with AL representing a radical monovalent alkyl and AR-NR ₂ H with AR representing a monovalent aryl radical. In this case,

- 33R1 represents an AL-NH ₂ radical with AL representing a monovalent alkyl radical, in this case a hexyl radical. The reagent has the following formula B1:

B1 The reagent of formula B1 is hexane-1,6-diamine.

Due to the presence of two -NH ₂ groups on the reagent of formula B1, the reaction products are numerous. Among them, there may be mentioned the main reaction products of the following formulas C1a, C1b:

C1a

C1b [0200] Mention may also be made of minority reaction products among which there is the reaction product of formula C1c below:

C1c [0201] Compound C1 is prepared from 1,4-benzene-dicarboxaldehyde (CAS 23-278) and hexane-1,6-diamine (CAS 124-09-4) in a polar solvent. Thus, for example, 20 g of hexane-1,6-diamine are dissolved in 250 ml of water. The solution is mixed and heated to 95 ° C. Then, 21 g of 1,4-benzene-dicarboxaldehyde are then added. The whole is maintained at 95 ° C. for 4 hours with stirring until precipitation of the compound C1. Then, the reaction mixture is filtered and washed 5 times consecutively with 100 ml of boiling water in order to remove the residues of hexane-1,6-diamine and 1,4-benzenedicarboxaldehyde. The final product is finally recovered and then dried in an oven for 48 hours at 70 ° C. 35 g of compound C1 are obtained in the form of a beige powder.

- 34 [0202] Comparative tests [0203] In a first step, the reinforcing filler was incorporated into an elastomer, by thermomechanically kneading the whole, until a maximum temperature of between 110 ° C. and 190 ° C. was reached. Then the assembly was cooled to a temperature below 110 ° C. Then, in a second step, the crosslinking system, the aromatic polyphenol and the aldehyde or the compound were incorporated. At the end of this second step, the mixture was heated to 150 ° C. until the maximum rheometric torque was obtained in order to vulcanize the composition and crosslink the resin. Then, a characterization of the stiffness at 23 ° C of the composition was carried out during a tensile test.

Characterization of the delay phase and of the rigidity at high temperature - Maximum rheometric torque [0205] The measurements are carried out at 150 ° C. with an oscillating chamber rheometer, according to standard DI N 53529 - part 3 (June 1983) . The evolution of the rheometric torque as a function of time describes the evolution of the stiffening of the composition as a result of the vulcanization and of the crosslinking of the resin. From the evolution of the rheometric couple, the presence of a delay phase is determined when the increase in the rheometric couple over 5 minutes of the composition tested is less than the increase in the rheometric couple over 5 minutes of a control composition comprising same aromatic polyphenol and the corresponding aldehyde, here composition T1. The presence of such a delay phase is indicated in Table 1. FIG. 2 represents the curve representing the evolution of the rheometric couple of the composition 11 as well as those representing the evolution of the rheometric couple of the compositions T0 and T1 . From the evolution of the rheometric torque, the maximum rheometric torque Cmax, also reported in Table 1, is determined. The higher the maximum rheometric torque Cmax, the more the composition has a rigidity which can be maintained at high temperature.

Characterization of the stiffness at 23 ° C - Tensile test [0208] These tests make it possible to determine the elasticity stresses and the properties at break. Unless otherwise indicated, they are carried out in accordance with standard ASTM D 412 of 1998 (test piece C). We measure in second elongation (i.e. after an accommodation cycle) the so-called nominal secant modules (or apparent constraints, in MPa) at 10% elongation (noted MA10). All of these tensile measurements are carried out under normal conditions of temperature and hygrometry, according to standard ASTM D 1349 of 1999 and reported in Table 1.

First, the results of Table 1 show that the use of an aromatic polyphenol and an aldehyde in the control composition T1 makes it possible to obtain a rigidity at 23 ° C. much higher than that of a composition devoid of reinforcing resin (T0). However, the composition T1 does not exhibit a delay phase so that the phenol5 aldehyde resin of the composition T1 crosslinks early.

Composition 11 has a delay phase and a rigidity substantially equivalent to that of composition T1 in the example described, and largely sufficient to allow reinforcement of the rubber composition. In addition, this rigidity can be increased by modifying other parameters such as the levels of aromatic polyphenol and of compounds used.

Composition 11 also exhibits excellent rigidity resistance at high temperatures and significantly improved compared to the control compositions T0 and T1.

In addition, composition 11 does not produce formaldehyde during its curing, for example by crosslinking or vulcanization.

It will also be noted that the delay phase and the stiffness at 23 ° C. can be chosen according to the application by varying the nature of R! and therefore the reagent of formula B or C making it possible to protect the aldehyde function or functions.

The invention is not limited to the embodiments described above.

-36Table 1

Composition Aromatic polyphenol Aldehyde Phase MA10 (MPa) Cmax delay (dN.m) TO 1 1 1 14.4 25 Tl Phloroglucinol (1) 1,4-benzenedicarboxaldehyde (2) No 53.1 58 Composition Aromatic Polyphenol Compound Phase MA10 (MPa, Cmax delay (dN.m) 11 Phloroglucinol (1) Compound Cl Yes 51.8 75

(1) 1,4-benzenedicarboxaldehyde (from ABCR; 98% purity).

Claims (29)

Claims 1. Compound, characterized in that it comes from the reaction between a reagent of formula A: and a reagent of formula B and / or C: H H ₂ NR! R ₂ -NRi (B) (C) in which: - Ar represents an aromatic ring, optionally substituted, the radical R ₃ represents a monovalent radical chosen from the group consisting of alkyl, aryl, AL-NH ₂ radicals with AL representing a monovalent alkyl radical, AR-NH ₂ with AR representing a monovalent aryl radical, AL-NR ₂ H with AL representing a monovalent alkyl radical and AR-NR ₂ H with AR representing a monovalent aryl radical, the radical R ₂ represents a monovalent hydrocarbon radical or a monovalent substituted hydrocarbon radical. 2. A compound according to claim 1, in which Ar is a six-membered aromatic ring. 3. A compound according to claim 2, in which the remainder of the aromatic ring Ar is unsubstituted. 4. Compound according to claim 2, in which the aromatic nucleus Ar is disubstituted. 5. Compound according to the preceding claim, in which the reagent A has the following formula Aa: 6. Compound according to claim 4 or 5, in which the two substituents of the aromatic ring Ar are in position para with respect to each other. 7. A compound according to any one of claims 2 to 6, in which Ar is a benzene aromatic ring. - 388. The compound of claim 1, wherein Ar is a five-membered aromatic ring. 9. A compound according to claim 8, in which the remainder of the aromatic ring Ar is unsubstituted. 10. Compound according to the preceding claim, in which the reagent of formula A has the following formula: in which X comprises N, S or O, preferably X represents O. 11. A compound according to claim 8, in which the aromatic nucleus Ar is disubstituted. 12. Compound according to the preceding claim, in which the reagent A has the following formula Ac: o (AC) in which X comprises N, S or O, preferably X represents O. 13. Compound according to the preceding claim, in which the reagent A has the following formula Ad: in which X comprises N, S or O, preferably X represents O. 14. Compound according to claim 1, in which the reagent of formula A is chosen from the group consisting of 1,4-benzene-dicarboxaldehyde, furfuraldehyde, 2,5-furanedicarboxaldehyde and mixtures of these reagents. 15. Compound according to any one of claims 1 to 14, in which the radical R! represents a monovalent radical chosen from the group consisting of AL-NH ₂ radicals with AL representing a monovalent alkyl radical, AR-NH ₂ with AR representing a monovalent aryl radical, AL-NR ₂ H with AL representing a monovalent alkyl radical and ARNR ₂ H with AR representing a monovalent aryl radical. - 3916. Compound according to any one of the preceding claims, in which the radical R ₂ represents a monovalent radical chosen from the group consisting of alkyl, aryl, arylalkyl, alkylaryl, cycloalkyl and alkenyl radicals. 17. Compound, characterized in that it is chosen from the group consisting of the 5 compounds of the following formulas: Z ₂ (l) (II) and mixtures of these compounds, in which: - Ar represents an aromatic nucleus, optionally substituted, - 7-y represents a monovalent radical chosen from the radicals of the following formulas: HN-Rx HN-Rx R ₂ \ N-Rx OH Rx Rx - Z ₂ represents a divalent radical of the following formula: OH OH -40in which: - the radical R! represents a monovalent radical chosen from the group consisting of alkyl, aryl, AL-NH ₂ radicals with AL representing a monovalent alkyl radical, AR-NH ₂ with AR representing a monovalent aryl radical, AL-NR ₂ H with AL representing a radical monovalent alkyl and AR-NR ₂ H with AR representing a monovalent aryl radical, the radical R ₂ represents a monovalent hydrocarbon radical or a monovalent substituted hydrocarbon radical. 18. The compound of claim 17, wherein Ar is a six-membered aromatic ring. 19. A compound according to claim 18, in which the remainder of the aromatic ring Ar is unsubstituted. 20. A compound according to claim 18, in which the aromatic ring Ar is di-substituted. 21. Compound according to the preceding claim, in which the compound is chosen from the group consisting of the compounds of the following formulas: (Ilia) (IVa) (Va) and their mixtures. 22. A compound according to claim 20 or 21, in which the two substituents of the aromatic ring Ar are in position para with respect to each other. 23. A compound according to any one of claims 18 to 22, wherein Ar is a benzene aromatic ring. 24. The compound of claim 17, wherein Ar is a five-membered aromatic ring. 25. A compound according to claim 24, in which the remainder of the aromatic ring Ar is unsubstituted. 26. Compound according to the preceding claim, in which the aromatic ring Ar has the following formula: - 41 in which X comprises N, S or O, preferably X represents O. 27. A compound according to claim 24, in which the aromatic ring Ar is di-substituted. 28. Compound according to the preceding claim, in which the compound is chosen from the group consisting of the compounds of the following formulas: (IIIb) (IVb) (Vb) and their mixtures. 29. Compound according to the preceding claim, in which the aromatic nucleus Ar has the following formula: in which X comprises N, S or O, preferably X represents O. 30. Compound according to the preceding claim, in which the two substituents of the aromatic ring Ar are in position 2 and 5 relative to one another. 31. Process for the manufacture of a compound according to any one of the preceding claims, in which the following are reacted: a reagent of formula A: and a reagent of formula B and / or C: H H ₂ NR ₂ -NR! (B) (C) in which: - Ar represents an aromatic nucleus, optionally substituted, -42 the radical R! represents a monovalent radical chosen from the group consisting of alkyl, aryl, AL-NH ₂ radicals with AL representing a monovalent alkyl radical, AR-NH ₂ with AR representing a monovalent aryl radical, AL-NR ₂ H with AL representing a radical monovalent alkyl and AR-NR ₂ H with AR representing a 5 monovalent aryl radical, the radical R ₂ represents a monovalent hydrocarbon radical or a monovalent substituted hydrocarbon radical. 32. Use of a compound according to any one of claims 1 to 30, for the manufacture of a resin for reinforcing a rubber composition. 33 33. Use according to the preceding claim, of the compound for generating a delay phase during the crosslinking of the resin, the resin being based on at least one aromatic polyphenol and at least the compound. 1/1