EP3245276B1 - Compositions of thermoassociative additives, the association of which is controlled, and lubricating compositions containing same - Google Patents

Description

FIELD OF THE INVENTION

The present invention relates to novel additive compositions which result from the mixture of at least two thermoassociative and exchangeable copolymers and of at least one compound making it possible to control the association of these two copolymers.

The invention also relates to a lubricating composition which results from the mixture of at least one lubricating base oil, of at least two thermoassociative and exchangeable copolymers and of at least one compound making it possible to control the association of these two copolymers.

The present invention also relates to a process for modulating the viscosity of a lubricating composition which results from the mixture of at least one lubricating base oil, of at least two thermoassociative and exchangeable copolymers; as well as the use of a diol compound to modulate the viscosity of a lubricating composition.

TECHNICAL BACKGROUND

Polymers of high molecular weight are widely used to increase the viscosity of solutions in many fields, such as petroleum, paper, water treatment, mining, cosmetics, textiles, and other industries. generally in all industrial techniques using thickened solutions.

However, these polymers of high molecular weight have the drawback of having a low resistance to permanent shear compared to the same polymers of smaller sizes. These shear stresses on polymers of high molecular weight lead to cleavages at the level of the macromolecular chains. The polymer thus degraded has reduced thickening properties, and the viscosity of the solutions containing it drops irreversibly. In addition, these polymers do not make it possible to modulate the thickening of the composition in which they are added as a function of the temperature of use of the composition.

The Applicant has set itself the objective of formulating new additive compositions which are more stable to shear compared to the compounds of the prior art and whose rheological behavior can be adapted as a function of the use of the composition in which these additives are added.

This objective is achieved thanks to the combination of associative and thermoreversible exchangeable additives and of an agent which makes it possible to control the association and the dissociation of these additives. The associated (potentially crosslinked) and exchangeable copolymers have the advantage of being more stable to shear stresses. This characteristic results from the combined use of two particular compounds, a random copolymer bearing diol functions and a compound comprising at least two boronic ester functions.

It is known from the document WO2013147795 polymers of which at least one monomer comprises boronic ester functions. These polymers are used for the manufacture of electronic devices, in particular for devices for which a flexible user interface is desired. These polymers are also used as a synthetic intermediate. They make it possible to functionalize the polymers by coupling with luminescent groups, electron transporting groups, etc. The coupling of these groups is carried out by conventional organic chemical reactions, involving the boron atom, such as, for example, the Suzuki coupling. However, no other use of these polymers, nor a combination with other compounds is envisaged.

It is also known from the document FR2855180 an aqueous fluid used in the exploitation of oil or gas deposits comprising at least one boronate polymer comprising at least one boronate or precursor function, and at least one ligand polymer having at least two groups capable of reacting with the one or more boronate or precursor functions.

The additive composition according to the invention has many advantages. It makes it possible to increase the viscosity of solutions, in particular of hydrophobic solutions, comprising them relative to the additive compositions of the prior art. The additives of the composition of the invention have an inverse behavior with respect to a modification of the temperature with respect to the behavior of the solution and of the rheological additives of polymer type of the prior art. It also makes it possible to adapt the increase in viscosity and the rheological behavior of these solutions as a function of their temperature of use.

The Applicant has also set itself the objective of formulating new lubricating compositions which make it possible to reduce the friction between two mechanical parts during cold use and during hot use.

The compositions used for the lubrication of mechanical parts generally consist of a base oil and additives. The base oil, in particular of petroleum or synthetic origin, exhibits variations in viscosity when the temperature is varied.

Indeed, when the temperature of a base oil increases, its viscosity decreases and when the temperature of the base oil decreases, its viscosity increases. However, the thickness of the protective film is proportional to the viscosity, and therefore also depends on the temperature. A composition exhibits good lubricating properties if the thickness of the protective film remains substantially constant whatever the conditions and the duration of use of the lubricant.

In an internal combustion engine, a lubricating composition can be subjected to external or internal temperature changes. External temperature changes are due to variations in ambient air temperature, such as temperature variations between summer and winter for example. Internal temperature changes result from the implementation of the motor. The temperature of an engine is lower during its starting phase, especially in cold weather, than during prolonged use. A lubricating composition that is too viscous at starting temperature can interfere with the movement of moving parts and thus prevent the engine from running fast enough. A lubricating composition must also be, on the one hand, sufficiently fluid to be able to reach the bearings rapidly and prevent wear thereof and, on the other hand, sufficiently thick to ensure good protection of the motor when the latter reaches its operating temperature. .

There is therefore a need to have available a lubricating composition having both good lubricating properties for the starting phases of an engine and for the operating phases of the engine at its operating temperature.

It is known to add additives improving the viscosity of a lubricating composition. The viscosity improving additives (or viscosity index improving additives) currently used are polymers such as polyalpha-olefins, polymethyl methacrylates, copolymers resulting from the polymerization of an ethylenic monomer and an alpha-olefin . These polymers are of high molecular weights. In general, the higher their molecular weight is, the greater the contribution of these polymers to viscosity control.

However, polymers of high molecular weight have the drawback of having a low resistance to permanent shear compared to polymers of the same nature but of smaller sizes. In addition, they thicken the lubricating compositions regardless of the operating temperature of the lubricating composition, and in particular at low temperature. The lubricating compositions of the prior art comprising additives improving viscosity can exhibit poor lubricating properties during the starting phases of an engine.

The lubricating composition according to the invention makes it possible to overcome the aforementioned drawbacks thanks to the combined use of a mixture of two thermoassociative and exchangeable compounds (a copolymer bearing diol functions and a compound comprising boronic ester functions) and of a compound diol in a lubricating base oil.

Unexpectedly, the Applicant has observed that the addition of a diol compound made it possible to control the association between a copolymer bearing diol functions and a compound comprising boronic ester functions. At low temperature, the polydiol copolymer is not or only slightly associated with the compounds comprising boronic ester functions; the latter reacting with the added diol compound. When the temperature increases, the diol functions of the copolymer react with the boronic ester functions of the compound comprising them by a transesterification reaction. The polydiol random copolymers and the compounds comprising boronic ester functions then bind together and can be exchanged. Depending on the functionality of the polydiols and of the compounds comprising boronic ester functions, as well as depending on the composition of the mixtures, a gel may form in the base oil. When the temperature decreases again, the boronic ester bonds between the random polydiol copolymers and the compounds comprising them break; the composition loses its gelled character if necessary. The Boronic ester functions of the compound comprising them react with the added diol compound. It is possible to modulate the kinetics and the temperature window for the formation of these associations, and therefore to modulate the rheological behavior of the lubricating composition as a function of the desired use.

It is possible, thanks to the compositions of the invention to provide lubricating compositions which have good lubricating properties during the starting phases of an engine (cold phase) and good lubricating properties when the engine is operating at its temperature. service (hot phase).

SUMMARY OF THE INVENTION

• un copolymère statistique polydiol A1,
• un copolymère statistique A2 comprenant au moins deux fonctions esters boroniques et pouvant s'associer avec ledit copolymère statistique polydiol A1 par au moins une réaction de transestérification,
• un composé exogène A4 choisi parmi les 1,2-diols et les 1,3-diols.

Thus, the subject of the invention is an additive composition resulting from the mixture of at least:

• a polydiol A1 random copolymer,
• a statistical copolymer A2 comprising at least two boronic ester functions and which can be combined with said polydiol A1 random copolymer by at least one transesterification reaction,
• an exogenous compound A4 chosen from 1,2-diols and 1,3-diols.

According to the invention, the molar percentage of exogenous compound A4, in the additive composition, relative to the boronic ester functions of the statistical copolymer A2 ranges from 0.025 to 5000%, preferably ranges from 0.1% to 1000%, from even more preferably from 0.5% to 500%, even more preferably from 1% to 150%.

• ▪ d'au moins un premier monomère M1 de formule générale (I) :
  
  dans laquelle :
  • R₁ est choisi parmi le groupe formé par -H, -CH₃, et -CH₂-CH₃ ;
  • x est un nombre entier allant de 1 à 18; de préférence de 2 à 18 ;
  • y est un nombre entier égal à 0 ou 1;
  • X₁ et X₂, identiques ou différents, sont choisis parmi le groupe formé par l'hydrogène, le tétrahydropyranyle, le méthyloxyméthyle, le ter-butyle, le benzyle, le triméthylsilyle et le t-butyle diméthylsilyle ;
    ou bien
  • X₁ et X₂ forment avec les atomes d'oxygène un pont de formule suivante
    
    dans laquelle:
    • les étoiles (*) symbolisent les liaisons aux atomes d'oxygène,
    • R'₂ et R"₂, identiques ou différents, sont choisis parmi le groupe formé par l'hydrogène et un alkyle en C₁-C₁₁, de préférence le méthyle;
    ou bien
  • X₁ et X₂ forment avec les atomes d'oxygène un ester boronique de formule suivante :
    
    dans laquelle :
    • les étoiles (*) symbolisent les liaisons aux atomes d'oxygène,
    • R'"₂ est choisi parmi le groupe formé par un aryle en C₆-C₁₈, un aralkyle en C₇-C₁₈ et alkyle en C₂-C₁₈, de préférence un aryle en C₆-C₁₈,
• ▪ avec au moins un second monomère M2 de formule générale (II) :
  
  dans laquelle :
  • R₂ est choisi parmi le groupe formé par -H, -CH₃ et -CH₂-CH₃ ,
  • R₃ est choisi parmi le groupe formé par un aryle en C₆-C₁₈, un aryle en C₆-C₁₈ substitué par un groupement R'₃, -C(O)-O-R'₃ ; -O-R'₃ , -S-R'₃ et -C(O)-N(H)-R'₃ avec R'₃ un groupe alkyle en C₁-C₃₀.

According to the invention, the random copolymer A1 results from the copolymerization:

• ▪ at least one first monomer M1 of general formula (I):
  
  in which :
  • R ₁ is selected from the group consisting of -H, -CH ₃ , and -CH ₂ -CH ₃ ;
  • x is an integer ranging from 1 to 18; preferably from 2 to 18;
  • y is an integer equal to 0 or 1;
  • X ₁ and X ₂ , identical or different, are chosen from the group formed by hydrogen, tetrahydropyranyl, methyloxymethyl, tert-butyl, benzyl, trimethylsilyl and t-butyl dimethylsilyl;
    or
  • X ₁ and X ₂ form with the oxygen atoms a bridge of the following formula
    
    in which:
    • the stars (*) symbolize the bonds to oxygen atoms,
    • R ′ ₂ and R ″ ₂ , identical or different, are chosen from the group formed by hydrogen and a C ₁ -C ₁₁ alkyl, preferably methyl;
    or
  • X ₁ and X ₂ together with the oxygen atoms form a boronic ester of the following formula:
    
    in which :
    • the stars (*) symbolize the bonds to oxygen atoms,
    • R '" ₂ is chosen from the group formed by a C ₆ -C ₁₈ aryl, a C ₇ -C ₁₈ aralkyl and C ₂ -C ₁₈ alkyl, preferably a C ₆ -C ₁₈ aryl,
• ▪ with at least one second M2 monomer of general formula (II):
  
  in which :
  • R ₂ is selected from the group formed by -H, -CH ₃ and -CH ₂ -CH ₃ ,
  • R ₃ is selected from the group consisting of a C ₆ -C ₁₈ aryl, C ₆ -C ₁₈ substituted by a group R _'3, -C (O) -O-R'_3; -O-R ' ₃ , -S-R' ₃ and -C (O) -N (H) -R ' ₃ with R' _{3 being} a C _{1 -C 30} alkyl group.

According to one embodiment of the invention, the random copolymer A1 results from the copolymerization of at least one monomer M1 with at least two monomers M2 having different _{R 3 groups.}

dans laquelle :

• R₂ est choisi parmi le groupe formé par -H, -CH₃ et-CH₂-CH₃,
• R"₃ est un groupe alkyle en C₁-C₄,

et l'autre monomère M2 du copolymère statistique A1 a pour formule générale (II-B) :

dans laquelle :

• R₂ est choisi parmi le groupe formé par -H, -CH₃ et-CH₂-CH₃
• R'"₃ est un groupe alkyle en C₁₅-C₃₀.

According to one embodiment of the invention, one of the M2 monomers of the random copolymer A1 has the general formula (II-A):

in which :

• R ₂ is selected from the group formed by -H, -CH ₃ and-CH ₂ -CH ₃ ,
• R " ₃ is a C _{1 -C 4} alkyl group,

and the other M2 monomer of the random copolymer A1 has the general formula (II-B):

in which :

• R ₂ is selected from the group formed by -H, -CH ₃ and-CH ₂ -CH ₃
• R '" ₃ is a C _{15 -C 30} alkyl group.

According to one embodiment of the invention, the side chains of the random copolymer A1 have an average length ranging from 8 to 20 carbon atoms, preferably from 9 to 15 carbon atoms.

According to the invention, the random copolymer A1 has a molar percentage of monomer M1 of formula (I) in said copolymer ranging from 1 to 30%, preferably from 5 to 25%, more preferably ranging from 9 to 21%.

• ▪ d'au moins un monomère M3 de formule (IV) :
  
  dans laquelle :
  • t est un nombre entier égal à 0 ou 1 ;
  • u est un nombre entier égal à 0 ou 1 ;
  • M et R₈ sont des groupements de liaison divalents, identiques ou différents, choisis parmi le groupe formé par un aryle en C₆-C₁₈, un aralkyle en C₇-C₂₄ et un alkyle en C₂-C₂₄, de préférence un aryle en C₆-C₁₈,
  • X est une fonction choisie parmi le groupe formé par -O-C(O)-, -C(O)-O-, -C(O)-N(H)-, -N(H)-C(O)- , -S- , -N(H)- , -N(R'₄)- et -O- avec R'₄ une chaîne hydrocarbonée comprenant de 1 à 15 atomes de carbone;
  • R₉ est choisi parmi le groupe formé par -H, -CH₃ et-CH₂-CH₃ ;
  • R₁₀ et R₁₁ identiques ou différents sont choisis parmi le groupe formé par l'hydrogène et un groupe hydrocarboné ayant de 1 à 24 atomes de carbone, de préférence entre 4 et 18 atomes de carbone, de préférence entre 6 et 14 atomes de carbone ;
• ▪ avec au moins un second monomère M4 de formule générale (V) :
  
  dans laquelle :
  • R₁₂ est choisi parmi le groupe formé par -H, -CH₃ et -CH₂-CH₃,
  • R₁₃ est choisi parmi le groupe formé par un aryle en C₆-C₁₈, un aryle en C₆-C₁₈ substitué par un groupement R'₁₃, -C(O)-O-R'₁₃; -O-R'₁₃, -S-R'₁₃ et -C(O)-N(H)-R'₁₃ avec R'₁₃ un groupe alkyle en C₁-C₂₅ .

According to one embodiment of the invention, the random copolymer A2 results from the copolymerization:

• ▪ at least one M3 monomer of formula (IV):
  
  in which :
  • t is an integer equal to 0 or 1;
  • u is an integer equal to 0 or 1;
  • M and R ₈ are divalent linking groups, identical or different, chosen from the group formed by a C ₆ -C ₁₈ aryl, a C ₇ -C ₂₄ aralkyl and a C ₂ -C ₂₄ alkyl, preferably a C ₆ -C ₁₈ aryl,
  • X is a function chosen from the group formed by -OC (O) -, -C (O) -O-, -C (O) -N (H) -, -N (H) -C (O) -, -S-, -N (H) -, -N (R ' ₄ ) - and -O- with R' ₄ a hydrocarbon chain comprising from 1 to 15 carbon atoms;
  • R ₉ is selected from the group consisting of -H, -CH ₃ and-CH ₂ -CH ₃ ;
  • R ₁₀ and R _{11, which are} identical or different, are chosen from the group formed by hydrogen and a hydrocarbon group having from 1 to 24 carbon atoms, preferably between 4 and 18 carbon atoms, preferably between 6 and 14 carbon atoms ;
• ▪ with at least one second monomer M4 of general formula (V):
  
  in which :
  • R ₁₂ is selected from the group formed by -H, -CH ₃ and -CH ₂ -CH ₃ ,
  • R ₁₃ is selected from the group consisting of a C ₆ -C ₁₈ aryl, C ₆ -C ₁₈ substituted by a group R _13, -C (O) -O-R _'13; -O-R _'13 , -S-R' ₁₃ and -C (O) -N (H) -R _'13 with R' _{13 being} a C _{1 -C 25} alkyl group.

According to one embodiment of the invention, the chain formed by the linking of groups R ₁₀ , M, X and (R ₈ ) _u with u equal to 0 or 1 of the monomer of general formula (IV) of the statistical copolymer A2 has a total number of carbon atoms ranging from 8 to 38, preferably 10 to 26.

According to one embodiment of the invention, the side chains of the random copolymer A2 have an average length greater than or equal to 8 carbon atoms, preferably ranging from 11 to 16 carbon atoms.

According to the invention, the random copolymer A2 has a molar percentage of monomer of formula (IV) in said copolymer ranging from 0.25 to 20%, preferably from 1 to 10%.

avec :

• w₃ un nombre entier égal à 0 ou 1 ;
• R₁₄ et R₁₅ identiques ou différents choisis parmi le groupe formé par l'hydrogène et un groupe hydrocarboné ayant de 1 à 24 atomes de carbone.

According to one embodiment of the invention, the exogenous compound A4 has the general formula (VI):

with :

• w ₃ an integer equal to 0 or 1;
• R ₁₄ and R ₁₅ identical or different selected from the group formed by hydrogen and a hydrocarbon group having from 1 to 24 carbon atoms.

According to one embodiment, the substituents R ₁₀ , R ₁₁ and the value of the index (t) of the monomer of formula (IV) of the random copolymer A2 are identical respectively to the substituents R ₁₄ , R ₁₅ and to the value of the index w ₃ , of the exogenous compound A4 of formula (VI).

According to one embodiment of the invention, at least one of the substituents R ₁₀ , R ₁₁ or the value of the index (t) of the monomer of formula (IV) of the random copolymer A2 is respectively different from the substituents R ₁₄ , R ₁₅ or the value of the index w ₃ , of the exogenous compound A4 of formula (VI).

According to the invention, the mass ratio between the polydiol A1 random copolymer and the A2 random copolymer (A1 / A2 ratio) ranges from 0.005 to 200, preferably from 0.05 to 20, even more preferably from 0.1 to 10, even more preferably from 0.2 to 5.

• d'une huile lubrifiante ; et
• d'une composition d'additifs définie ci-dessus.

The present invention also relates to a lubricating composition resulting from the mixture of at least:

• lubricating oil; and
• of an additive composition defined above.

According to one embodiment of the invention, the lubricating oil is chosen from oils from group I, group II, group III, group IV, group V of the API classification and one of their mixture.

According to one embodiment of the invention, the mass ratio between the random copolymer A1 and the random copolymer A2 (ratio A1 / A2) ranges from 0.005 to 100, preferably from 0.05 to 20 and even more preferably from 0 , 1 to 10, even more preferably from 0.2 to 5.

According to one embodiment of the invention, the molar percentage of exogenous compound A4 relative to the boronic ester functions of the statistical copolymer A2 ranges from 0.05 to 5000%, preferably ranges from 0.1% to 1000%, so even more preferably from 0.5% to 500%, even more preferably from 1% to 150%.

According to one embodiment of the invention, the lubricating composition of the invention results from the further mixing of a functional additive chosen from the group formed by detergents, anti-wear additives, extreme pressure additives, additional antioxidants. , polymers improving the viscosity index, pour point improvers, antifoams, anticorrosion additives, thickeners, dispersants, friction modifiers and mixtures thereof.

• la fourniture d'une composition lubrifiante résultant du mélange d'au moins une huile lubrifiante, d'au moins un copolymère statistique polydiol A1 et d'au moins un copolymère statistique A2 comprenant au moins deux fonctions esters boroniques et pouvant s'associer avec ledit copolymère statistique polydiol A1 par au moins une réaction de transestérification,
• l'ajout dans ladite composition lubrifiante d'au moins un composé exogène A4 choisi parmi les 1,2-diols et les 1,3-diols.

The present invention also relates to a method for modulating the viscosity of a lubricating composition, the method comprising at least:

• the supply of a lubricating composition resulting from the mixture of at least one lubricating oil, of at least one polydiol A1 random copolymer and at least one A2 random copolymer comprising at least two boronic ester functions and which can be combined with said polydiol A1 random copolymer by at least one transesterification reaction,
• the addition to said lubricating composition of at least one exogenous compound A4 chosen from 1,2-diols and 1,3-diols.

The invention also provides the use of at least one compound chosen from 1,2-diols or 1,3 diols for modulating the viscosity of a lubricating composition, said lubricating composition resulting from the mixture of at least one oil. lubricant, at least one polydiol A1 random copolymer and at least one A2 random copolymer comprising at least two boronic ester functions and which can be combined with said polydiol A1 random copolymer by at least one transesterification reaction.

BRIEF DESCRIPTION OF THE FIGURES

• The figure 1 schematically represents a random copolymer (P1), a gradient copolymer (P2) and a block copolymer (P3), each circle represents a monomer unit. The difference in chemical structure between the monomers is symbolized by a different color (light gray / black).
• The figure 2 schematically represents a comb copolymer.
• The figure 3 schematically illustrates the crosslinking between a polydiol A1 copolymer and a compound bearing at least two boronic ester functions in the presence of exogenous A4 diol compounds. The Figure 3 does not represent a composition according to the invention.
• The figure 4 schematically shows the behavior of the composition of the invention as a function of temperature. A random copolymer having diol functions (function A) can combine thermoreversibly with a random copolymer having boronic ester functions (function B) via a reversible transesterification reaction. A chemical bond of the boronic ester type is then formed between the two polymers. The free diol compounds (C function) present in the medium in the form of small organic molecules make it possible to adjust the degree of association between the copolymers carrying the diol A functions and the copolymers carrying the boronic ester B functions.
• The figure 5 represents the evolution of the relative viscosity (without unit, the y-axis) as a function of the temperature (° C, the x-axis) of compositions A, C, D and E.
• The figure 6 represents the evolution of the relative viscosity (without unit, the y-axis) as a function of the temperature (° C, the x-axis) of compositions A, B and F.
• The figure 7 represents the evolution of the elastic modulus (G ') and of the viscous modulus (G ") (Pa, the y-axis) as a function of the temperature (° C, the x-axis) of composition G.
• The figure 8 represents the evolution of the elastic modulus (G ') and of the viscous modulus (G ") (Pa, the y-axis) as a function of the temperature (° C, the x-axis) of the composition H.
• The figure 9 schematically illustrates the reactions of exchange of boronic ester bonds between two random polydiol polymers (A1-1 and A1-2) and two random boronic ester polymers (A2-1 and A2-2) in the presence of exogenous diol compounds (A4 ) and diol compounds released in situ (A3).

DESCRIPTION OF EMBODIMENTS OF THE INVENTION

Composition d'additifs selon l'invention :

Additive composition according to the invention:

• un copolymère statistique polydiol A1,
• un composé A2, notamment un copolymère statistique A2, comprenant au moins deux fonctions esters boroniques et pouvant s'associer avec ledit copolymère statistique polydiol A1 par une réaction de transestérification,
• un composé exogène A4 choisi parmi les 1,2-diols et les 1,3-diols.

A first subject of the present invention is a composition of associative and thermoreversibly exchangeable additives, the degree of association of which is controlled by the presence of a so-called exogenous compound, the composition resulting from the mixture of at least:

• a polydiol A1 random copolymer,
• a compound A2, in particular a statistical copolymer A2, comprising at least two boronic ester functions and which can be combined with said polydiol A1 random copolymer by a transesterification reaction,
• an exogenous compound A4 chosen from 1,2-diols and 1,3-diols.

This composition of additives makes it possible to modulate the rheological behavior of a medium in which it is added. The medium can be a hydrophobic medium, in particular nonpolar, such as a solvent, a mineral oil, a natural oil, a synthetic oil.

∘ Polydiol A1 random copolymers

The polydiol A1 random copolymer results from the copolymerization of at least one first monomer M1 carrying diol functions and at least one second monomer M2, with a chemical structure different from that of the monomer M1.

The term “copolymer” is understood to mean an oligomer or a linear or branched macromolecule having a block consisting of several repeating units (or monomer unit), at least two of which have a different chemical structure.

By “monomer unit” or “monomer” is meant a molecule capable of being converted into an oligomer or a macromolecule by combination with itself or with other molecules of the same type. A monomer refers to the smallest constituent unit whose repetition leads to an oligomer or a macromolecule.

By “random copolymer” is meant an oligomer or a macromolecule in which the sequential distribution of the monomer units obeys known statistical laws. For example, a copolymer is said to be statistical when it is constituted by monomer units whose distribution is a Markovian distribution. A schematic random polymer (P1) is shown in figure 1 . The distribution in the polymer chain of the monomer units depends on the reactivity of the polymerizable functions of the monomers and on the relative concentration of the monomers. The polydiol random copolymers of the invention are distinguished from block copolymers and copolymers with gradients. The term “block” denotes a part of a copolymer comprising several identical or different monomer units and which have at least one particular feature of constitution or configuration making it possible to distinguish it from its adjacent parts. A schematic block copolymer (P3) is illustrated in figure 1 . A gradient copolymer denotes a copolymer of at least two monomer units of different structures whose monomer composition changes gradually along the polymer chain, thus gradually passing from one end of the polymer chain rich in a unit. monomer, at the other end rich in the other comonomer. A schematic gradient polymer (P2) is illustrated in figure 1 .

The term “copolymerization” is understood to mean a process which makes it possible to convert a mixture of at least two monomer units of different chemical structures into an oligomer or into a copolymer.

In the remainder of the present application, “B” represents a boron atom.

The term “C ₁ -C _j alkyl” means a saturated, linear or branched hydrocarbon chain comprising from i to j carbon atoms. For example, the term “C ₁ -C ₁₀ alkyl” means a saturated, linear or branched hydrocarbon chain comprising from 1 to 10 carbon atoms.

By “C ₆ -C ₁₈ aryl” is meant a functional group which is derived from an aromatic hydrocarbon compound comprising from 6 to 18 carbon atoms. This functional group can be monocyclic or polycyclic. By way of illustration, a C ₆ -C ₁₈ aryl can be phenyl, naphthalene, anthracene, phenanthrene and tetracene.

The term “C ₂ -C ₁₀ alkenyl” means a linear or branched hydrocarbon chain comprising at least one unsaturation, preferably a carbon-carbon double bond, and comprising from 2 to 10 carbon atoms.

The term “C ₇ -C ₁₈ aralkyl” means an aromatic hydrocarbon compound, preferably monocyclic, substituted by at least one linear or branched alkyl chain and in which the total number of carbon atoms of the aromatic ring and of its substituents is from 7 to 18 carbon atoms. By way of illustration, a C ₇ -C ₁₈ aralkyl can be chosen from the group formed by benzyl, tolyl and xylyl.

The term “C ₆ -C ₁₈ aryl group substituted with an R ′ _{3 group} ” is understood to mean an aromatic hydrocarbon compound, preferably monocyclic, comprising from 6 to 18 carbon atoms of which at least one carbon atom of the aromatic ring is substituted. by a group R ' ₃ .

By “Hal” or “halogen” is meant a halogen atom chosen from the group formed by chlorine, bromine, fluorine and iodine.

• M1 monomer

dans laquelle :

• R₁ est choisi parmi le groupe formé par -H, -CH₃ et -CH₂-CH₃, de préférence -H et -CH₃;
• x est un nombre entier allant de 1 à 18, de préférence allant de 2 à 18; de manière plus préférée de 3 à 8 ; de manière encore plus préférée x est égal à 4 ;
• y est un nombre entier égal à 0 ou 1; de préférence y est égal à 0 ;
• X₁ et X₂, identiques ou différents, sont choisis parmi le groupe formé par l'hydrogène, le tétrahydropyranyle, le méthyloxyméthyle, le ter-butyle, le benzyle, le triméthylsilyle et le t-butyle diméthylsilyle ;
  ou bien
• X₁ et X₂ forment avec les atomes d'oxygène un pont de formule suivante :
  
  dans laquelle :
  • les étoiles (*) symbolisent les liaisons aux atomes d'oxygène,
  • R'₂ et R"₂, identiques ou différents, sont choisis parmi le groupe formé par l'hydrogène et un groupe alkyle en C₁-C₁₁ ; ou bien
• X₁ et X₂ forment avec les atomes d'oxygène un ester boronique de formule suivante :
  
  dans laquelle :
  • les étoiles (*) symbolisent les liaisons aux atomes d'oxygène,
  • R'"₂ est choisi parmi le groupe formé par un aryle en C₆-C₁₈, un aralkyle en C₇-C₁₈ et un alkyle en C₂-C₁₈, de préférence un aryle en C₆-C₁₈, de manière plus préférée le phényle.

The first monomer M1 of the polydiol random copolymer (A1) of the invention has the general formula (I):

in which :

• R ₁ is selected from the group formed by -H, -CH ₃ and -CH ₂ -CH ₃ , preferably -H and -CH ₃ ;
• x is an integer ranging from 1 to 18, preferably ranging from 2 to 18; more preferably from 3 to 8; even more preferably x is equal to 4;
• y is an integer equal to 0 or 1; preferably y is equal to 0;
• X ₁ and X ₂ , identical or different, are chosen from the group formed by hydrogen, tetrahydropyranyl, methyloxymethyl, tert-butyl, benzyl, trimethylsilyl and t-butyl dimethylsilyl;
  or
• X ₁ and X ₂ form with the oxygen atoms a bridge of the following formula:
  
  in which :
  • the stars (*) symbolize the bonds to oxygen atoms,
  • R ′ ₂ and R ″ ₂ , identical or different, are chosen from the group formed by hydrogen and a C _{1 -C 11} alkyl group; or else
• X ₁ and X ₂ together with the oxygen atoms form a boronic ester of the following formula:
  
  in which :
  • the stars (*) symbolize the bonds to oxygen atoms,
  • R '" ₂ is selected from the group formed by a C ₆ -C ₁₈ aryl, a C ₇ -C ₁₈ aralkyl and a C ₂ -C ₁₈ alkyl, preferably a C ₆ -C ₁₈ aryl, of more preferably phenyl.

Preferably, when R ′ ₂ and R ″ ₂ is a C _{1 -C 11} alkyl group; the hydrocarbon chain is a linear chain. Preferably, the C _{1 -C 11} alkyl group is chosen from the group formed by methyl , ethyl, n-propyl, n-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, n-nonyl, n-decycle and n-undecyl. More preferably, the C _{1 -C 11} alkyl group is methyl.

Preferably, when R '" ₂ is a C _{2 -C 18} alkyl group, the hydrocarbon chain is a straight chain.

dans laquelle :

• R₁ est choisi parmi le groupe formé par -H, -CH₃ et -CH₂-CH₃, de préférence -H et -CH₃;
• x est un nombre entier allant de 1 à 18, de préférence allant de 2 à 18; de manière plus préférée de 3 à 8 ; de manière encore plus préférée x est égal à 4 ;
• y est un nombre entier égal à 0 ou 1; de préférence y est égal à 0.

Among the monomers of formula (I), the monomers corresponding to formula (IA) are among the preferred:

in which :

• R ₁ is selected from the group formed by -H, -CH ₃ and -CH ₂ -CH ₃ , preferably -H and -CH ₃ ;
• x is an integer ranging from 1 to 18, preferably ranging from 2 to 18; more preferably from 3 to 8; even more preferably x is equal to 4;
• y is an integer equal to 0 or 1; preferably y is equal to 0.

dans laquelle :

• R₁ est choisi parmi le groupe formé par -H, -CH₃ et -CH₂-CH₃, de préférence -H et -CH₃;
• x est un nombre entier allant de 1 à 18, de préférence allant de 2 à 18; de manière plus préférée de 3 à 8 ; de manière encore plus préférée x est égal à 4 ;
• y est un nombre entier égal à 0 ou 1; de préférence y est égal à 0 ;
• Y₁ et Y₂, identiques ou différents, sont choisis parmi le groupe formé par le tétrahydropyranyle, le méthyloxyméthyle, le ter-butyle, le benzyle, le triméthylsilyle et le t-butyle diméthylsilyle ;
  ou bien
• Y₁ et Y₂ forment avec les atomes d'oxygène un pont de formule suivante :
  
  dans laquelle :
  • les étoiles (*) symbolisent les liaisons aux atomes d'oxygène,
  • R'₂ et R"₂, identiques ou différents, sont choisis parmi le groupe formé par l'hydrogène et un groupe alkyle en C₁-C₁₁ ;
  ou bien
• Y₁ et Y₂ forment avec les atomes d'oxygène un ester boronique de formule suivante :
  
  dans laquelle :
  • les étoiles (*) symbolisent les liaisons aux atomes d'oxygène,
  • R'"₂ est choisi parmi le groupe formé par un aryle en C₆-C₁₈, un aralkyle en C₇-C₁₈ et un alkyle en C₂-C₁₈, de préférence un aryle en C₆-C₁₈, de manière plus préférée le phényle.

Among the monomers of formula (I), the monomers corresponding to formula (IB) are among the preferred:

in which :

• R ₁ is selected from the group formed by -H, -CH ₃ and -CH ₂ -CH ₃ , preferably -H and -CH ₃ ;
• x is an integer ranging from 1 to 18, preferably ranging from 2 to 18; more preferably from 3 to 8; even more preferably x is equal to 4;
• y is an integer equal to 0 or 1; preferably y is equal to 0;
• Y ₁ and Y ₂ , identical or different, are chosen from the group formed by tetrahydropyranyl, methyloxymethyl, tert-butyl, benzyl, trimethylsilyl and t-butyl dimethylsilyl;
  or
• Y ₁ and Y ₂ form with the oxygen atoms a bridge of the following formula:
  
  in which :
  • the stars (*) symbolize the bonds to oxygen atoms,
  • R ′ ₂ and R ″ ₂ , identical or different, are chosen from the group formed by hydrogen and a C _{1 -C 11} alkyl group;
  or
• Y ₁ and Y ₂ form with the oxygen atoms a boronic ester of the following formula:
  
  in which :
  • the stars (*) symbolize the bonds to oxygen atoms,
  • R "_'2 is selected from the group consisting of a C ₆ -C ₁₈ aralkyl and C ₇ -C ₁₈ alkyl, C ₂ -C _18, preferably aryl C ₆ -C ₁₈ , more preferably phenyl.

Preferably, when R ′ ₂ and R ″ ₂ is a C _{1 -C 11} alkyl group; the hydrocarbon chain is a linear chain. Preferably, the C _{1 -C 11} alkyl group is chosen from the group formed by methyl , ethyl, n-propyl, n-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, n-nonyl, n-decycle and n-undecyl. More preferably, the C _{1 -C 11} alkyl group is methyl.

Preferably, when R '" ₂ is a C _{2 -C 18} alkyl group, the hydrocarbon chain is a straight chain.

• Obtaining the M1 monomer

avec R₁, Y₁, Y₂, x et y tels que définis dans la formule générale (I-B) décrite ci-dessus.Monomer M1 of general formula (IA) is obtained by deprotection of the alcohol functions of the monomer of general formula (IB) according to reaction scheme 1 below:

with R ₁ , Y ₁ , Y ₂ , x and y as defined in general formula (IB) described above.

The deprotection reaction of the diol functions of the monomer of general formula (IB) is well known to those skilled in the art. He knows how to adapt the reaction conditions of deprotection according to the nature of the protecting groups Y ₁ and Y ₂ .

dans lequel :

• Y₃ est choisi parmi le groupe formé par un atome d'halogène, de préférence le chlore, -OH et O-C(O)-R'₁ avec R'₁ choisi parmi le groupe formé par -H, -CH₃ et -CH₂-CH₃ , de préférence -H et -CH₃;
• R₁, Y₁, Y₂, x et y ont la même signification que celle donnée dans formule générale (I-B).

Monomer M1 of general formula (IB) can be obtained by reaction of a compound of general formula (Ic) with an alcohol compound of general formula (Ib) according to reaction scheme 2 below:

in which :

• Y ₃ is chosen from the group formed by a halogen atom, preferably chlorine, -OH and OC (O) -R ' ₁ with R' ₁ chosen from the group formed by -H, -CH ₃ and -CH ₂ -CH ₃ , preferably -H and -CH ₃ ;
• R ₁ , Y ₁ , Y ₂ , x and y have the same meaning as given in general formula (IB).

These coupling reactions are well known to those skilled in the art.

The compound of general formula (I-c) is commercially available from the suppliers: Sigma-Aldrich® and Alfa Aesar®.

avec x, y, Y₁ et Y₂ tels que définis dans la formule générale (I-B).The alcohol compound of general formula (Ib) is obtained from the corresponding polyol of formula (Ia) by protection of the diol functions according to the following reaction scheme 3:

with x, y, Y ₁ and Y ₂ as defined in general formula (IB).

The reaction for protecting the diol functions of the compound of general formula (Ia) is well known to those skilled in the art. He knows how to adapt the reaction conditions of protection according to the nature of the protecting groups Y ₁ and Y ₂ used.

The polyol of general formula (Ia) is commercially available from the suppliers: Sigma-Aldrich® and Alfa Aesar®.

• M2 monomer

dans laquelle :

• R₂ est choisi parmi le groupe formé par -H, -CH₃ et -CH₂-CH₃ de préférence -H et -CH₃ ;
• est choisi parmi le groupe formé par un groupement aryle en C₆-C₁₈, un aryle en C₆-C₁₈ substitué par un groupement R'₃, -C(O)-O-R'₃ ; -O-R'₃, -S-R'₃ et -C(O)-N(H)-R'₃ avec R'₃ un groupe alkyle en C₁-C₃₀.

The second monomer of the random copolymer of the invention has the general formula (II):

in which :

• R ₂ is chosen from the group formed by -H, -CH ₃ and -CH ₂ -CH ₃ , preferably -H and -CH ₃ ;
• is selected from the group consisting of aryl, C ₆ -C ₁₈ aryl, C ₆ -C ₁₈ substituted by a group R _3, -C (O) -O-R _'3; -O-R ' ₃ , -S-R' ₃ and -C (O) -N (H) -R ' ₃ with R' _{3 being} a C _{1 -C 30} alkyl group.

Preferably, R ′ ₃ is a C _{1 -C 30} alkyl group whose hydrocarbon chain is linear.

dans laquelle :

• R₂ est choisi parmi le groupe formé par -H, -CH₃ et -CH₂-CH₃, de préférence -H et -CH₃ ;
• R"₃ est un groupe alkyle en C₁-C₄.

Among the monomers of formula (II), the monomers corresponding to formula (II-A) are among the preferred:

in which :

• R ₂ is selected from the group formed by -H, -CH ₃ and -CH ₂ -CH ₃ , preferably -H and -CH ₃ ;
• R " ₃ is a C _{1 -C 4} alkyl group.

By “C _{1 -C 14} alkyl group” is meant a saturated, linear or branched hydrocarbon chain comprising from 1 to 14 carbon atoms. Preferably, the hydrocarbon chain is linear. Preferably, the hydrocarbon chain comprises from 4 to 12 carbon atoms.

dans laquelle :

• R₂ est choisi parmi le groupe formé par -H, -CH₃ et -CH₂-CH₃ , de préférence -H et -CH₃;
• R'"₃ est un groupe alkyle en C₁₅-C₃₀.

Among the monomers of formula (II), the monomers corresponding to the formula (II-B) are also among the preferred ones:

in which :

• R ₂ is chosen from the group formed by -H, -CH ₃ and -CH ₂ -CH ₃ , preferably -H and -CH ₃ ;
• R '" ₃ is a C _{15 -C 30} alkyl group.

By “C _{15 -C 30} alkyl group” is meant a saturated, linear or branched hydrocarbon chain comprising from 15 to 30 carbon atoms. Preferably, the hydrocarbon chain is linear. Preferably, the hydrocarbon chain comprises from 16 to 24 carbon atoms.

• Obtaining the M2 monomer

The monomers of formula (II), (II-A) and, (II-B) are well known to those skilled in the art. They are marketed by Sigma-Aldrich® and TCI®.

• Preferred polydiol copolymers

• un premier monomère M1 de formule générale (I) tel que décrit précédemment ; notamment de formule générale (I-A) telle que décrit précédemment ;
• un second monomère M2 de formule (II) tel que décrit précédemment, dans laquelle R₂ est -H et est un groupement aryle en C₆-C₁₈ ; de préférence est le phényle.

In one embodiment, a preferred random copolymer results from the copolymerization of at least:

• a first monomer M1 of general formula (I) as described above; in particular of general formula (IA) as described above;
• a second M2 monomer of formula (II) as described above, in which R ₂ is -H and is a C ₆ -C ₁₈ aryl group; preferably is phenyl.

• un premier monomère M1 de formule générale (I) tel que décrit précédemment ; notamment de formule générale (I-A) telle que décrit précédemment ;
• un second monomère M2 de formule (II-A) tel que décrit précédemment ; et
• un troisième monomère M2 de formule (II-B) tel que décrit précédemment.

In another embodiment, a preferred random copolymer results from the copolymerization of at least:

• a first monomer M1 of general formula (I) as described above; in particular of general formula (IA) as described above;
• a second M2 monomer of formula (II-A) as described above; and
• a third M2 monomer of formula (II-B) as described above.

• un premier monomère M1 de formule générale (I) tel que décrit précédemment ; notamment de formule générale (I-A) telle que décrit précédemment ;
• un second monomère M2 de formule (II-A) dans laquelle R₂ est -CH₃ et R"₃ est un groupe alkyle en C₄-C₁₂, de préférence un alkyle linéaire en C₄-C₁₂ ;
• un troisième monomère M2 de formule (II-B) dans laquelle R₂ est -CH₃ et R'"₃ est un groupe alkyle en C₁₆-C₂₄, de préférence un alkyle linéaire en C₁₆-C₂₄.

According to this other embodiment, a preferred random copolymer results from the copolymerization of at least:

• a first monomer M1 of general formula (I) as described above; in particular of general formula (IA) as described above;
• a second M2 monomer of formula (II-A) in which R ₂ is -CH ₃ and R " ₃ is a C _{4 -C 12} alkyl group, preferably a linear C _{4 -C 12} alkyl group;
• a third M2 monomer of formula (II-B) in which R ₂ is -CH ₃ and R '" ₃ is a C _{16 -C 24} alkyl group, preferably a linear C _{16 -C 24} alkyl group.

• un premier monomère M1 de formule générale (I) tel que décrit précédemment ; notamment de formule générale (I-A) telle que décrit précédemment ;
• un second monomère M2 choisi dans le groupe formé par le méthacrylate de n-octyle, le méthacrylate de n-décyle et le méthacrylate de n-dodécyle ;
• un troisième monomère M2 choisi dans le groupe formé par le méthacrylate de palmityle, le méthacrylate de stéaryle, le méthacrylate d'arachidyle et le méthacrylate de béhényle.

According to this embodiment, a preferred random copolymer results from the copolymerization of at least:

• a first monomer M1 of general formula (I) as described above; in particular of general formula (IA) as described above;
• a second M2 monomer chosen from the group formed by methacrylate of n-octyl, n-decyl methacrylate and n-dodecyl methacrylate;
• a third M2 monomer chosen from the group formed by palmityl methacrylate, stearyl methacrylate, arachidyl methacrylate and behenyl methacrylate.

• Process for obtaining polydiol copolymers

Those skilled in the art are able to synthesize polydiol A1 random copolymers using their general knowledge.

The copolymerization can be initiated in bulk or in solution in an organic solvent by compounds which generate free radicals. For example, the copolymers of the invention are obtained by the known processes of radical copolymerization, in particular controlled such as the method called radical polymerization controlled by reversible chain transfer by addition-fragmentation (in English: Reversible Addition-Fragmentation Chain Transfer (RAFT )) and the method called controlled radical polymerization by atom transfer (in English Atom Transfer Radical Polymerization (ARTP)). Conventional radical polymerization and telomerization can also be used to prepare the copolymers of the invention ( Moad, G .; Solomon, DH, The Chemistry of Radical Polymerization. 2nd ed .; Elsevier Ltd: 2006; p 639 ; Matyaszewski, K .; Davis, TP Handbook of Radical Polymerization; Wiley-Interscience: Hoboken, 2002; p 936 ).

1. i) un premier monomère M1 de formule générale (I) telle que décrite précédemment:
2. ii) au moins un second monomère M2 de formule générale (II) :
3. iii) au moins une source de radicaux libres.

The polydiol A1 random copolymer is prepared according to a preparation process which comprises at least one polymerization step (a) in which at least:

1. i) a first monomer M1 of general formula (I) as described above:
2. ii) at least one second M2 monomer of general formula (II):
3. iii) at least one source of free radicals.

In one embodiment, the method may further comprise iv) at least one chain transfer agent.

By “a source of free radicals” is meant a chemical compound making it possible to generate a chemical species having one or more unpaired electrons on its outer layer. Those skilled in the art can use any source of free radicals known per se and suitable for polymerization processes, in particular controlled radical polymerization. Among the sources of free radicals, preferred are, by way of illustration, benzoyl peroxide, tert-butyl peroxide, diazo compounds such as azobisisobutyronitrile, peroxygen compounds such as persulphates or hydrogen peroxide, systems redox such as the oxidation of Fe ²⁺ , persulphate / sodium-metabisulphite mixtures, or ascorbic acid / hydrogen peroxide or else compounds cleavable photochemically or by ionizing radiation, for example ultraviolet rays or by beta or gamma radiation.

The term “chain transfer agent” means a compound the purpose of which is to ensure homogeneous growth of the macromolecular chains by reversible transfer reactions between growing species, ie polymer chains terminated by a carbon radical, and dormant species, ie polymer chains terminated by a transfer agent. This reversible transfer process makes it possible to control the molecular masses of the copolymers thus prepared. Preferably in the process of the invention, the chain transfer agent comprises a thiocarbonylthio -SC (= S) - group. By way of illustration of chain transfer agent, mention may be made of dithioesters, trithiocarbonates, xanthates and dithiocarbamates. A preferred transfer agent is cumyl dithiobenzoate or 2-cyano-2-propyl benzodithioate.

The term “chain transfer agent” also means a compound the purpose of which is to limit the growth of macromolecular chains during formation by addition of monomer molecules and to initiate new chains, which makes it possible to limit the molecular masses. finals, or even to control them. Such a type of transfer agent is used in telomerization. A preferred transfer agent is cysteamine.

• au moins une étape de polymérisation (a) telle que définie ci-dessus, dans laquelle les monomères M1 et M2 sont choisis avec X₁ et X₂ différents de l'hydrogène, et en outre
• au moins une étape de déprotection (b) des fonctions diol du copolymère obtenu à l'issue de l'étape (a), de façon à obtenir un copolymère dans lequel X₁ et X₂ sont identiques et sont un atome d'hydrogène.

In one embodiment, the process for preparing a polydiol random copolymer comprises:

• at least one polymerization step (a) as defined above, in which the monomers M1 and M2 are chosen with X ₁ and X ₂ other than hydrogen, and in addition
• at least one step of deprotection (b) of the diol functions of the copolymer obtained at the end of step (a), so as to obtain a copolymer in which X ₁ and X ₂ are identical and are a hydrogen atom.

In one embodiment, the polymerization step (a) comprises bringing at least one M1 monomer into contact with at least two M2 monomers having different groups.

In this embodiment, one of the monomers M2 has the general formula (II-A) as defined above and the other monomer M2 has the general formula (II-B) as defined above.

The preferences and definitions described for the general formulas (I), (I-A), (I-B), (II-A), (II-B) also apply to the processes described above.

• Properties of A1 polydiol copolymers

The polydiol A1 random copolymers are comb copolymers.

By “comb copolymers” is meant a copolymer having a main chain (also called backbone) and side chains. The side chains are dangling on either side of the main chain. The length of each side chain is less than the length of the main chain. The figure 2 schematically represents a comb polymer.

The A1 copolymers have a backbone of polymerizable functions, in particular a backbone of methacrylate functions or of styrene functions, and a mixture of hydrocarbon side chains substituted or not by diol functions.

As the monomers of formula (I) and (II) exhibit polymerizable functions of Identical or substantially identical reactivity, a copolymer is obtained in which the monomers having diol functions are statistically distributed along the backbone of the copolymer relative to the monomers whose alkyl chains are unsubstituted by diol functions.

Polydiol A1 random copolymers have the advantage of being sensitive to external stimuli, such as temperature, pressure, shear rate; this sensitivity resulting in a change in properties. In response to a stimulus, the conformation in space of the copolymer chains is modified and the diol functions are made more or less accessible to association reactions, which can generate crosslinking, as well as to exchange reactions. These processes of association and exchange are reversible. The random copolymer A1 is a thermosensitive copolymer, that is to say it is sensitive to changes in temperature.

Advantageously, the side chains of the polydiol A1 random copolymer have an average length ranging from 8 to 20 carbon atoms, preferably from 9 to 15 carbon atoms. By “average side chain length” is meant the average length of the side chains of each monomer constituting the copolymer. Those skilled in the art know how to obtain this average length by appropriately selecting the types and the ratio of monomers constituting the polydiol random copolymer. The choice of this average chain length makes it possible to obtain a polymer which is soluble in a hydrophobic medium, whatever the temperature at which the copolymer is dissolved. The polydiol A1 random copolymer is therefore miscible in a hydrophobic medium. By “hydrophobic medium” is meant a medium which does not have or has a very low affinity for water, that is to say that it is not miscible in water or in an aqueous medium.

The polydiol A1 random copolymer has a molar percentage of M1 monomer of formula (I) in said copolymer ranging from 1 to 30%, preferably 5 to 25%, more preferably ranging from 9 to 21%.

In a preferred embodiment, the polydiol A1 random copolymer has a molar percentage of M1 monomer of formula (I) in said copolymer ranging from 1 to 30%, preferably 5 to 25%, more preferably ranging from 9 to 21 %, a molar percentage of M2 monomer of formula (II-A) in said copolymer ranging from 8 to 92% and a molar percentage of M2 monomer of formula (II-B) in said copolymer ranging from 0.1 to 62%. The molar percentage of monomers in the copolymer results directly from the adjustment of the amounts of monomers used for the synthesis of the copolymer.

In a preferred embodiment, the polydiol A1 random copolymer has a molar percentage of monomer M1 of formula (I) in said copolymer ranging from 1 to 30%, a molar percentage of monomer M2 of formula (II-A) in said copolymer ranging from 8 to 62% and a molar percentage of monomer M2 of formula (II-B) in said copolymer ranging from 8 to 91%. The molar percentage of monomers in the copolymer results directly from the adjustment of the amounts of monomers used for the synthesis of the copolymer.

Advantageously, the polydiol A1 random copolymer has a number-average degree of polymerization ranging from 100 to 2000, preferably from 150 to 1000. In a known manner, the degree of Polymerization is controlled using a controlled radical polymerization technique, a telomerization technique or by adjusting the amount of free radical source when the copolymers of the invention are prepared by conventional radical polymerization.

Advantageously, the polydiol A1 random copolymer has a polydispersity index (Ip) ranging from 1.05 to 3.75; preferably ranging from 1.10 to 3.45. The polydispersity index is obtained by measurement of size exclusion chromatography using a polystyrene calibration.

Advantageously, the polydiol A1 random copolymer has a number-average molar mass ranging from 10,000 to 400,000 g / mol, preferably from 25,000 to 150,000 g / mol, the number-average molar mass being obtained by measurement of chromatography d steric exclusion using polystyrene calibration.

The method of measuring size exclusion chromatography using a polystyrene calibration is described in the book ( Fontanille, M .; Gnanou, Y., Chemistry and physical chemistry of polymers. 2nd ed .; Dunod: 2010; p 546 ).

∘ Compound A2 • Compound A2 boronic diester

dans laquelle :

• w₁ et w₂, identiques ou différents sont des nombres entiers égaux à 0 ou 1,
• R₄, R₅, R₆ et R₇, identiques ou différents, sont choisis parmi le groupe formé par l'hydrogène et un groupe hydrocarboné ayant de 1 à 24 atomes de carbone, de préférence de 4 à 18 atomes de carbone, de préférence de 6 à 14 atomes de carbone ;
• L est un groupement de liaison divalent et choisi parmi le groupe formé par un aryle en C₆-C₁₈, un aralkyle en C₇-C₂₄ et une chaîne hydrocarbonée en C₂-C₂₄, de préférence un aryle en C₆-C₁₈.

In one embodiment, the compound A2 comprising two boronic ester functions has the general formula (III):

in which :

• w ₁ and w ₂ , identical or different, are whole numbers equal to 0 or 1,
• R ₄ , R ₅ , R ₆ and R ₇ , identical or different, are chosen from the group formed by hydrogen and a hydrocarbon group having from 1 to 24 carbon atoms, preferably from 4 to 18 carbon atoms, of preferably from 6 to 14 carbon atoms;
• L is a divalent linking group and selected from the group formed by a C ₆ -C ₁₈ aryl, a C ₇ -C ₂₄ aralkyl and a C ₂ -C ₂₄ hydrocarbon chain, preferably a C ₆ - aryl. C ₁₈ .

The term “hydrocarbon-based group having from 1 to 24 carbon atoms” is understood to mean an alkyl or alkenyl group, linear or branched, having from 1 to 24 carbon atoms. Preferably the group hydrocarbon comprises 4 to 18 carbon atoms, preferably 6 to 14 carbon atoms. Preferably, the hydrocarbon group is linear alkyl.

The term “C ₂ -C ₂₄ hydrocarbon-based chain” means an alkyl or alkenyl group, linear or branched, comprising from 2 to 24 carbon atoms. Preferably, the hydrocarbon chain is a linear alkyl group. Preferably, the hydrocarbon chain comprises from 6 to 16 carbon atoms.

• w₁ et w₂, identiques ou différents sont des nombres entiers égaux à 0 ou 1;
• R₄ et R₆ sont identique et sont des atomes d'hydrogène ;
• R₅ et R₇ sont identiques et sont un groupe hydrocarboné, de préférence un alkyle linéaire, ayant de 1 à 24 atomes de carbone, de préférence de 4 à 18 atomes de carbone, de préférence de 6 à 16 atomes de carbone ;
• L est un groupement de liaison divalent et est un aryle en C₆-C₁₈, de préférence le phényle.

In one embodiment of the invention, compound A2 is a compound of general formula (III) above in which:

• w ₁ and w ₂ , identical or different, are whole numbers equal to 0 or 1;
• R ₄ and R ₆ are the same and are hydrogen atoms;
• R ₅ and R ₇ are the same and are a hydrocarbon group, preferably linear alkyl, having 1 to 24 carbon atoms, preferably 4 to 18 carbon atoms, preferably 6 to 16 carbon atoms;
• L is a divalent linking group and is C ₆ -C ₁₈ aryl, preferably phenyl.

avec w₁, w₂, L, R₄, R₅, R₆ et R₇, tels que définis ci-dessus.The compound A2 boronic diester of formula (III) as described above is obtained by a condensation reaction between a boronic acid of general formula (III-a) and diol functions of compounds of general formula (III-b) and (III-c) according to reaction scheme 4 below:

with w ₁ , w ₂ , L, R ₄ , R ₅ , R ₆ and R ₇ , as defined above.

Indeed, by condensation of the boronic acid functions of compound (III-a) with diol functions of compounds of formula (III-b) and of formula (III-c), compounds having two boronic ester functions (compound of formula (III)). This step is carried out according to means well known to those skilled in the art.

In the context of the present invention, the compound of general formula (III-a) is dissolved, in the presence of water, in a polar solvent such as acetone. The presence of water makes it possible to shift the chemical equilibria between the boronic acid molecules of formula (III-a) and the boroxine molecules obtained from the boronic acids of formula (III-a). Indeed, it is well known that boronic acids can spontaneously form boroxine molecules at room temperature. However, the presence of boroxine molecules is undesirable in the context of the present invention.

The condensation reaction is carried out in the presence of a dehydrating agent such as magnesium sulfate. This agent makes it possible to trap the water molecules initially introduced as well as those which are released by the condensation between the compound of formula (III-a) and the compound of formula (III-b) and between the compound of formula (III- a) and the compound of formula (III-c).

In one embodiment, the compound (III-b) and the compound (III-c) are the same.

Those skilled in the art know how to adapt the amounts of reagents of formula (III-b) and / or (III-c) and of formula (III-a) to obtain the product of formula (III).

• Compound A2 random poly (boronic ester) copolymer

In another embodiment, compound A2 comprising at least two boronic ester functions is a poly (boronic ester) random copolymer resulting from the copolymerization of at least one M3 monomer of formula (IV) as described below with at minus one M4 monomer of formula (V) as described below.

In the remainder of the application, the expressions “boronic ester random copolymer” or “poly (boronic ester) random copolymer” are equivalent and denote the same copolymer.

✔ M3 monomer of formula (IV)

dans laquelle :

• t est un nombre entier égal à 0 ou 1 ;
• u est un nombre entier égal à 0 ou 1 ;
• M et R₈ sont des groupements de liaison divalent, identiques ou différents, et sont choisis parmi le groupe formé par un aryle en C₆-C₁₈, un aralkyle en C₇-C₂₄ et alkyle en C₂-C₂₄, de préférence un aryle en C₆-C₁₈,
• X est une fonction choisie parmi le groupe formé par -O-C(O)-, -C(O)-O-, -C(O)-N(H)-, -N(H)-C(O)- , -S- , -N(H)- , -N(R'₄)- et -O- avec R'₄ une chaîne hydrocarbonée comprenant de 1 à 15 atomes de carbone;
• R₉ est choisi parmi le groupe formé par -H, -CH₃ et-CH₂-CH₃; de préférence -H et -CH₃;
• R₁₀ et R₁₁, identiques ou différents, sont choisis parmi le groupe formé par l'hydrogène et une chaîne hydrocarbonée ayant de 1 à 24 atomes de carbone, de préférence entre 4 et 18 atomes de carbone, de préférence entre 6 et 12 atomes de carbone ;

The M3 monomer of compound A2 boronic ester random copolymer has the general formula (IV) in which:

in which :

• t is an integer equal to 0 or 1;
• u is an integer equal to 0 or 1;
• M and R ₈ are divalent linking groups, identical or different, and are chosen from the group formed by a C ₆ -C ₁₈ aryl, a C ₇ -C ₂₄ aralkyl and C ₂ -C ₂₄ alkyl, of preferably a C ₆ -C ₁₈ aryl,
• X is a function chosen from the group formed by -OC (O) -, -C (O) -O-, -C (O) -N (H) -, -N (H) -C (O) -, -S-, -N (H) -, -N (R ' ₄ ) - and -O- with R' ₄ a hydrocarbon chain comprising from 1 to 15 carbon atoms;
• R ₉ is selected from the group consisting of -H, -CH ₃ and-CH ₂ -CH ₃ ; preferably -H and -CH ₃ ;
• R ₁₀ and R ₁₁ , identical or different, are chosen from the group formed by hydrogen and a hydrocarbon chain having from 1 to 24 carbon atoms, from preferably between 4 and 18 carbon atoms, preferably between 6 and 12 carbon atoms;

The term “C ₂ -C ₂₄ alkyl” means a saturated, linear or branched hydrocarbon chain comprising from 2 to 24 carbon atoms. Preferably, the hydrocarbon chain is linear. Preferably, the hydrocarbon chain comprises from 6 to 16 carbon atoms.

By “hydrocarbon chain comprising from 1 to 15 carbon atoms” is meant a linear or branched alkyl or alkenyl group comprising from 1 to 15 carbon atoms. Preferably, the hydrocarbon chain is a linear alkyl group. Preferably, it comprises from 1 to 8 carbon atoms.

By “hydrocarbon chain comprising from 1 to 24 carbon atoms” is meant a linear or branched alkyl or alkenyl group comprising from 1 to 24 carbon atoms. Preferably, the hydrocarbon chain is a linear alkyl group. Preferably, it comprises from 4 to 18 carbon atoms, preferably between 6 and 12 carbon atoms.

• t est un nombre entier égal à 0 ou 1 ;
• u est un nombre entier égal à 0 ou 1 ;
• M et R₈ sont des groupements de liaison divalents et sont différents, M est un aryle en C₆-C₁₈, de préférence le phényle, R₈ est un aralkyle en C₇-C₂₄, de préférence le benzyle ;
• X est une fonction choisie parmi le groupe formé par -O-C(O)-, -C(O)-O-, -C(O)-N(H)- et -O- , de préférence -C(O)-O- ou -O-C(O)- ;
• R₉ est choisi parmi le groupe formé par -H, -CH₃, de préférence -H;
• R₁₀ et R₁₁ sont différents, l'un des groupes R₁₀ ou R₁₁ est H et l'autre groupe R₁₀ ou R₁₁ est une chaîne hydrocarbonée, de préférence un groupe alkyle linéaire, ayant de 1 à 24 atomes de carbone, de préférence entre 4 et 18 atomes de carbone, de préférence entre 6 et 12 atomes de carbone.

In one embodiment, the M3 monomer has the general formula (IV) in which:

• t is an integer equal to 0 or 1;
• u is an integer equal to 0 or 1;
• M and R ₈ are divalent linking groups and are different, M is C ₆ -C ₁₈ aryl, preferably phenyl, R ₈ is C ₇ -C ₂₄ aralkyl, preferably benzyl;
• X is a function selected from the group formed by -OC (O) -, -C (O) -O-, -C (O) -N (H) - and -O-, preferably -C (O) - O- or -OC (O) -;
• R ₉ is selected from the group formed by -H, -CH ₃ , preferably -H;
• R ₁₀ and R ₁₁ are different, one of the groups R ₁₀ or R ₁₁ is H and the other group R ₁₀ or R ₁₁ is a hydrocarbon chain, preferably a linear alkyl group, having from 1 to 24 carbon atoms , preferably between 4 and 18 carbon atoms, preferably between 6 and 12 carbon atoms.

✔ Synthesis of the M3 monomer of formula (IV)

In all the diagrams presented below, unless otherwise indicated, the variables R ₁₀ , R ₁₁ , M, u, t, X, R ₈ , R ' ₄ and R ₉ have the same definition as in formula (IV) below -above.

The M3 monomers of formula (IV) are obtained in particular from a preparation process comprising at least one step of condensing a boronic acid of general formula (IV-f) with a diol compound of general formula (IV-g ) according to reaction scheme 5 below:

In fact, by condensation of the boronic acid functions of the compound of formula (IV-f) with diol functions of the compounds of formula (IV-g), a boronic ester compound of formula (IV) is obtained. This step is carried out according to methods well known to those skilled in the art.

In the context of the present invention, the compound of general formula (IV-f) is dissolved, in the presence of water, in a polar solvent such as acetone. The condensation reaction takes place in the presence of a dehydrating agent, such as magnesium sulfate.

The compounds of formula (IV-g) are commercially available from the following suppliers: Sigma-Aldrich®, Alfa Aesar® and TCI®.

avec

• z un nombre entier égal à 0 ou 1 ;
• R₁₂ est choisi parmi le groupe formé par -H, -CH₃ et -CH₂-CH₃ ;
• u, X, M, R₈ et R₉ tels que définis ci-dessus.

The compound of formula (IV-f) is obtained directly from the compound of formula (IV-e) by hydrolysis according to the following reaction scheme 6:

with

• z an integer equal to 0 or 1;
• R ₁₂ is selected from the group consisting of -H, -CH ₃ and -CH ₂ -CH ₃ ;
• u, X, M, R ₈ and R ₉ as defined above.

avec

• z, u, R₁₂, M, R'₄, R₉ et R₈ tels que définis ci-dessus ; et dans ce schéma lorsque :
  • X représente -O-C(O)-, alors Y₄ représente une fonction alcool -OH ou un atome d'halogène, de préférence le chlore ou le brome et Y₅ est une fonction acide carboxylique -C(O)-OH ;
  • X représente -C(O)-O-, alors Y₄ représente une fonction acide carboxylique -C(O)-OH et Y₅ est une fonction alcool -OH ou un atome d'halogène, et de préférence le chlore ou le brome;
  • X représente -C(O)-N(H)-, alors Y₄ représente une fonction acide carboxylique -C(O)-OH ou une fonction -C(O)-Hal, et Y₅ est une fonction aminé NH₂ ;
  • X représente -N(H)-C(O)- , alors Y₄ représente une fonction aminé NH₂ et Y₅ est une fonction acide carboxylique -C(O)-OH ou une fonction -C(O)-Hal ;
  • X représente -S-, alors Y₄ est un atome d'halogène et Y₅ est une fonction thiol -SH ou bien Y₄ est une fonction thiol -SH et Y₅ est un atome d'halogène ;
  • X représente -N(H)- , alors Y₄ est un atome d'halogène et Y₅ est une fonction amine -NH₂ ou bien Y₄ est une fonction amine -NH₂ et Y₅ est un atome d'halogène;
  • X représente -N(R'₄)- , alors Y₄ est un atome d'halogène et Y₅ est une fonction aminé -N(H)(R'₄) ou bien Y₄ est une fonction aminé -N(H)(R'₄) et Y₅ est un atome d'halogène;
  • X représente -O-, alors Y₄ est un atome d'halogène et Y₅ est une fonction alcool -OH ou bien Y₄ est une fonction alcool -OH et Y₅ est un atome d'halogène.

The compound of formula (IV-e) is obtained by reacting a compound of formula (IV-c) with a compound of formula (IV-d) according to the following reaction scheme 7:

with

• z, u, R ₁₂ , M, R ' ₄ , R ₉ and R ₈ as defined above; and in this diagram when:
  • X represents -OC (O) -, then Y ₄ represents an alcohol function -OH or a halogen atom, preferably chlorine or bromine and Y ₅ is a carboxylic acid function -C (O) -OH;
  • X represents -C (O) -O-, then Y ₄ represents a carboxylic acid function -C (O) -OH and Y ₅ is an alcohol function -OH or a halogen atom, and preferably chlorine or bromine ;
  • X represents -C (O) -N (H) -, then Y ₄ represents a carboxylic acid function -C (O) -OH or a -C (O) -Hal function, and Y ₅ is an NH ₂ amine function;
  • X represents -N (H) -C (O) -, then Y ₄ represents an NH ₂ amino function and Y ₅ is a -C (O) -OH carboxylic acid function or a -C (O) -Hal function;
  • X represents -S-, then Y ₄ is a halogen atom and Y ₅ is a thiol function -SH or Y ₄ is a thiol function -SH and Y ₅ is a halogen atom;
  • X represents -N (H) -, then Y ₄ is a halogen atom and Y ₅ is an amine function -NH ₂ or Y ₄ is an amine function -NH ₂ and Y ₅ is a halogen atom;
  • X represents -N (R ' ₄ ) -, then Y ₄ is a halogen atom and Y ₅ is an amine function -N (H) (R' ₄ ) or else Y ₄ is an amine function -N (H) (R ' ₄ ) and Y ₅ is a halogen atom;
  • X represents -O-, then Y ₄ is a halogen atom and Y ₅ is an alcohol function -OH or else Y ₄ is an alcohol function -OH and Y ₅ is a halogen atom.

These esterification, etherification, thioetherification, alkylation or condensation reactions between an amine function and a carboxylic acid function are well known to those skilled in the art. Those skilled in the art therefore know how to choose, as a function of the chemical nature of the groups Y ₁ and Y _2, the reaction conditions to obtain the compound of formula (IV-e).

The compounds of formula (IV-d) are commercially available from the suppliers: Sigma-Aldrich®, TCI® and Acros Organics®.

avec M, Y₄, z et R₁₂ tels que définis ci-dessus,The compound of formula (IV-c) is obtained by a condensation reaction between a boronic acid of formula (IV-a) with at least one diol compound of formula (IV-b) according to the following reaction scheme 8:

with M, Y ₄ , z and R ₁₂ as defined above,

Among the compounds of formula (IV-b), the one in which R ₁₂ is methyl and z = 0 is preferred.

The compounds of formula (IV-a) and (IV-b) are commercially available from the following suppliers Sigma-Aldrich®, Alfa Aesar® and TCI®.

✔ Monomer M4 of general formula (V):

dans laquelle :

• R₁₂ est choisi parmi le groupe formé par -H, -CH₃ et -CH₂-CH₃, de préférence -H et -CH₃ ;
• R₁₃ est choisi parmi le groupe formé par un aryle en C₆-C₁₈, un aryle en C₆-C₁₈ substitué par un groupement R'₁₃, -C(O)-O-R'₁₃ ; -O-R'₁₃, -S-R'₁₃ et -C(O)-N(H)-R'₁₃ avec R'₁₃ un groupe alkyle en C₁-C₂₅ .

The monomer M4 of compound A2 random copolymer boronic ester has the general formula (V)

in which :

• R ₁₂ is selected from the group formed by -H, -CH ₃ and -CH ₂ -CH ₃ , preferably -H and -CH ₃ ;
• R ₁₃ is selected from the group consisting of a C ₆ -C ₁₈ aryl, C ₆ -C ₁₈ substituted by a group R _13, -C (O) -O-R _'13; -O-R _'13 , -S-R' ₁₃ and -C (O) -N (H) -R _'13 with R' _{13 being} a C _{1 -C 25} alkyl group.

The term “C _{1 -C 25} alkyl group” means a saturated, linear or branched hydrocarbon chain comprising from 1 to 25 carbon atoms. Preferably, the hydrocarbon chain is linear.

The term “C ₆ -C ₁₈ aryl group substituted with an R ₁₃ group” is understood to mean an aromatic hydrocarbon compound comprising from 6 to 18 carbon atoms of which at least one carbon atom of the aromatic ring is substituted by a C alkyl group. ₁ -C ₂₅ as defined above.

dans laquelle :

• R₂ est choisi parmi le groupe formé par -H, -CH₃ et -CH₂-CH₃, de préférence - H et -CH₃ ;
• R'₁₃ un groupe alkyle en C₁-C₂₅, de préférence un alkyle linéaire en C₁-C₂₅, de manière encore plus préféré un alkyle linéaire en C₅-C₁₅.

Among the monomers of formula (V), the monomers corresponding to formula (VA) are among the preferred:

in which :

• R ₂ is selected from the group formed by -H, -CH ₃ and -CH ₂ -CH ₃ , preferably - H and -CH ₃ ;
• R _{'13 is} a C _{1 -C 25} alkyl group, preferably a linear C ₁ -C ₂₅ alkyl, even more preferably a linear C ₅ -C ₁₅ alkyl.

✔ Obtaining the M4 monomer:

The monomers of formulas (V) and (V-A) are well known to those skilled in the art. They are marketed by Sigma-Aldrich® and TCI®.

✔ Synthesis of compound A2 random poly (boronic ester) copolymer

Those skilled in the art are able to synthesize the boronic ester random copolymers by calling on their general knowledge. The copolymerization can be initiated in bulk or in solution in an organic solvent by compounds which generate free radicals. For example, the boronic ester random copolymers are obtained by the known radical copolymerization processes, in particular controlled such as the method called radical polymerization controlled by reversible chain transfer by addition-fragmentation (in English: Reversible Addition-Fragmentation Chain Transfer (RAFT) ) and the method called atom transfer controlled radical polymerization (in English Atom Transfer Radical Polymerization (ARTP)). Conventional radical polymerization and telomerization can also be used to prepare the copolymers of the invention ( Moad, G .; Solomon, DH, The Chemistry of Radical Polymerization. 2nd ed .; Elsevier Ltd: 2006; p 639 ; Matyaszewski, K .; Davis, TP Handbook of Radical Polymerization; Wiley-Interscience: Hoboken, 2002; p 936 )).

1. i) un premier monomère M3 de formule générale (IV) telle que définie précédemment ;
2. ii) au moins un second monomère M4 de formule générale (V) telle que définie précédemment:
3. iii) au moins une source de radicaux libres.

The boronic ester random copolymer is prepared according to a process which comprises at least one polymerization step (a) in which at least:

1. i) a first M3 monomer of general formula (IV) as defined above;
2. ii) at least one second monomer M4 of general formula (V) as defined above:
3. iii) at least one source of free radicals.

In one embodiment, the method may further comprise iv) at least one agent chain transfer.

The preferences and definitions described for general formulas (IV) and (V) also apply to the process.

The sources of radicals and the transfer agents are those which have been described for the synthesis of random polydiol copolymers. The preferences described for radical sources and transfer agents also apply to this process.

✔ Properties of compounds A2 random copolymers poly (boronic ester)

Advantageously, the chain formed by linking the groups R ₁₀ , M, (R ₈ ) _u with u, an integer equal to 0 or 1, and X of the monomer M3 of general formula (IV) has a total number of carbon atoms ranging from 8 to 38, preferably ranging from 10 to 26.

Advantageously, the side chains of the boronic ester random copolymer have an average length greater than 8 carbon atoms, preferably ranging from 11 to 16. This chain length makes it possible to dissolve the boronic ester random copolymer in a hydrophobic medium. By “average side chain length” is meant the average length of the side chains of each monomer constituting the copolymer. Those skilled in the art know how to obtain this average length by appropriately selecting the types and the ratio of monomers constituting the boronic ester random copolymer.

The boronic ester random copolymer has a molar percentage of monomer of formula (IV) in said copolymer ranging from 0.25 to 20%, preferably from 1 to 10%.

Advantageously, the boronic ester random copolymer has a molar percentage of monomer of formula (IV) in said copolymer ranging from 0.25 to 20%, preferably from 1 to 10% and a molar percentage of monomer of formula (V) in said copolymer ranging from 80 to 99.75%, preferably from 90 to 99%.

Advantageously, the boronic ester random copolymer has a number-average degree of polymerization ranging from 50 to 1500, preferably from 80 to 800.

Advantageously, the boronic ester random copolymer has a polydispersity index (Ip) ranging from 1.04 to 3.54; preferably ranging from 1.10 to 3.10. These values are obtained by size exclusion chromatography using tetrahydrofuran as eluent and polystyrene calibration.

Advantageously, the boronic ester random copolymer has a number-average molar mass ranging from 10,000 to 200,000 g / mol, preferably from 25,000 to 100,000 g / mol. These values are obtained by size exclusion chromatography using tetrahydrofuran as eluent and polystyrene calibration.

Compound A2, in particular the boronic ester random copolymer, has the property of being able to react in a hydrophobic medium, in particular nonpolar, with a compound carrying diol function (s) by a transesterification reaction. This transesterification reaction can be represented according to diagram 9 below:

Thus, during a transesterification reaction, a boronic ester is formed with a chemical structure different from the starting boronic ester by exchange of the hydrocarbon groups symbolized by

∘ Exogenous compound A4

The exogenous compound A4 is chosen from 1,2 diols and 1,3 diols. For the purposes of the present invention, the term “exogenous compound” means a compound which is added to the composition of additives resulting from the mixture of at least one polydiol random copolymer A1 and of at least one compound A2, in particular the poly random copolymer. (boronic ester).

dans laquelle :

• w3 est un nombre entier égal à 0 ou 1,
• R₁₄ et R₁₅, identiques ou différents, sont choisis parmi le groupe formé par l'hydrogène et une chaîne hydrocarbonée ayant de 1 à 24 atomes de carbone, de préférence entre 4 et 18 atomes de carbone, de préférence entre 6 et 12 atomes de carbone ;
• Par « chaîne hydrocarbonée comprenant de 1 à 24 atomes de carbone » on entend, un groupe alkyle ou alkenyle linéaire ou ramifié, comprenant de 1 à 24 atomes de carbone. De préférence, la chaîne hydrocarbonée est un groupe alkyle linéaire. De préférence, elle comprend de 4 à 18 atomes de carbone, de préférence entre 6 et 12 atomes de carbone.

The exogenous compound A4 can have the general formula (VI):

in which :

• w3 is an integer equal to 0 or 1,
• R ₁₄ and R ₁₅ , identical or different, are chosen from the group formed by hydrogen and a hydrocarbon chain having from 1 to 24 carbon atoms, preferably between 4 and 18 carbon atoms, preferably between 6 and 12 atoms of carbon ;
• By “hydrocarbon chain comprising from 1 to 24 carbon atoms” is meant a linear or branched alkyl or alkenyl group comprising from 1 to 24 carbon atoms. Preferably, the hydrocarbon chain is a linear alkyl group. Preferably, it comprises from 4 to 18 carbon atoms, preferably between 6 and 12 carbon atoms.

• w₃ est un nombre entier égal à 0 ou 1 ;
• R₁₄ et R₁₅ sont différents, l'un des groupes R₁₄ ou R₁₅ est H et l'autre groupe R₁₄ ou R₁₅ est une chaîne hydrocarbonée, de préférence un groupe alkyle linéaire, ayant de 1 à 24 atomes de carbone, de préférence entre 4 et 18 atomes de carbone, de préférence entre 6 et 12 atomes de carbone.

In one embodiment, the exogenous compound A4 has the general formula (VI) in which:

• w ₃ is an integer equal to 0 or 1;
• R ₁₄ and R ₁₅ are different, one of the groups R ₁₄ or R ₁₅ is H and the other group R ₁₄ or R ₁₅ is a hydrocarbon chain, preferably a linear alkyl group, having from 1 to 24 carbon atoms, preferably between 4 and 18 carbon atoms, preferably between 6 and 12 carbon atoms.

In one embodiment, the exogenous compound A4 has a different chemical structure from the diol compound A3 released in situ by a transesterification reaction. In this embodiment, at least one of the substituents R ₁₄ , R ₁₅ or the value of the index w ₃ of the exogenous compound A4 of formula (VI) is different respectively from the substituents R ₄ and R ₅ or from the value of l 'index w ₁ or the substituents R ₅ and R ₇ or the value of the index w ₂ of the boronic diester compound A2 of formula (III) or is different respectively from the substituents R ₁₀ , R ₁₁ or the value of the index t of the monomer (IV) of the poly (boronic ester) random copolymer A2.

In another embodiment, the exogenous compound A4 has a chemical structure identical to the diol compound A3 released in situ by a transesterification reaction. In this embodiment, the substituents R ₁₄ , R ₁₅ and the value of the index w ₃ of the exogenous compound A4 of formula (VI) is identical respectively to the substituents R ₄ and R ₅ and to the value of the index w ₁ or to R ₅ and R ₇ and to the value of the index w ₂ of the boronic diester compound A2 of formula (III) or is identical respectively to the substituents R ₁₀ , R ₁₁ and to the value of the index t of the monomer (IV) of the poly (boronic ester) random copolymer A2. Depending on its temperature of use, the composition of additives resulting from the mixture of at least one polydiol A1 random copolymer, of at least one A2 compound, in particular an A2 random copolymer, comprising at least two boronic ester functions and which may s' associate with said polydiol A1 random copolymer by a transesterification reaction, and an addition of at least one exogenous compound A4 as defined above, may further comprise a compound A3 diol released in situ, identical to the exogenous compound A4 added in the composition.

For the purposes of the present invention, the term “diol released in situ” means the compound carrying a diol function, this compound being produced in the additive composition during the exchange of the hydrocarbon groups of the boronic ester compound A2, in particular of the random poly (boronic ester) copolymer, during the transesterification reaction. The random polymer A1 polydiol is not a diol released in situ within the meaning of the present invention.

Compounds of formula (VI) are commercially available from the following suppliers: Sigma-Aldrich®, Alfa Aesar® and TCI®.

✔ Characteristic of the new additive compositions of the invention

The additive compositions of the invention resulting from the mixture of at least one polydiol A1 random copolymer as defined above, of at least one A2 compound as defined above, in particular of at least one poly ( boronic ester) as defined above, and at least one exogenous compound A4 as defined above exhibit very varied rheological properties as a function of the temperature and according to the proportion of compounds A1, A2 and A4 used.

The polydiol A1 random copolymers and the A2 compounds as defined above have the advantage of being associative and of exchanging chemical bonds in a thermoreversible manner, in particular in a hydrophobic medium, in particular an apolar hydrophobic medium.

Under certain conditions, the polydiol A1 random copolymers and the A2 compounds as defined above can be crosslinked.

The polydiol random copolymers A1 and the compounds A2 also have the advantage of being exchangeable.

The term “associative” is understood to mean that covalent chemical bonds of the boronic ester type are established between the polydiol A1 random copolymers and the A2 compounds comprising at least two boronic ester functions, in particular with the poly (boronic ester) random copolymer. Depending on the functionality of the A1 polydiols and of the A2 compounds and depending on the composition of the mixtures, the formation of covalent bonds between the A1 polydiols and the A2 compounds may or may not lead to the formation of a three-dimensional polymer network.

The term “chemical bond” is understood to mean a covalent chemical bond of the boronic ester type.

The term “exchangeable” is understood to mean that the compounds are capable of exchanging chemical bonds with one another without the total number and the nature of the chemical functions being modified. The boronic ester bonds of the A2 compounds, the boronic ester bonds formed by transesterification reaction between the boronic esters of the A2 compounds and the exogenous A4 compounds, as well as the boronic ester bonds formed by association of the polydiol A1 random copolymers and of the A2 compounds can s 'exchange with diol functions carried by the exogenous compounds A4 or carried by the compounds A3 released in situ to form new boronic esters and new diol functions without the total number of boronic ester functions and diol functions being affected.

In the presence of exogenous A4 compounds, the boronic ester bonds of the A2 compounds as well as the boronic ester bonds formed by association of the A1 polydiol random copolymers and of the A2 compounds can also be exchanged to form new boronic esters without the total number of functions. boronic esters are not affected. This other process of exchanges of chemical bonds is carried out by metathesis reaction, via successive exchanges of the boronic ester functions in the presence of diol compounds (compounds A3 released in situ and exogenous compounds A4); this process is illustrated in figure 9 . The polydiol A1-1 random copolymer, which was associated with the A2-1 polymer, exchanged a boronic ester bond with the A2-2 boronic ester random copolymer. The polydiol A1-2 random copolymer, which was associated with the A2-2 polymer, exchanged a boronic ester bond with the A2-1 boronic ester random copolymer; the total number of boronic ester bonds in the composition being unchanged and is equal to 4. The copolymer A1-1 is then combined both with the polymer A2-1 and with the copolymer A2-2. The A1-2 copolymer is then combined both with the A2-1 copolymer and with the A2-2 copolymer.

Another chemical bond exchange process is illustrated in figure 9 , in which it can be observed that the polydiol A1-1 random copolymer, which was associated with the A2-1 polymer, has exchanged two boronic ester bonds with the A2-2 boronic ester random copolymer. The polydiol A1-2 random copolymer, which was in combination with the A2-2 polymer, exchanged two boronic ester bonds with the A2-1 boronic ester random copolymer; the total number of boronic ester bonds in the composition being unchanged and is equal to 4. The copolymer A1-1 is then combined with the polymer A2-2. The A1-2 copolymer is then combined with the A2-1 polymer. The A2-1 copolymer was exchanged with the A2-2 polymer.

The term “crosslinked” is understood to mean a copolymer in the form of a network obtained by the establishment of bridges between the macromolecular chains of the copolymer. These interconnected chains are mostly distributed in the three dimensions of space. A crosslinked copolymer forms a three-dimensional network. In practice, the formation of a copolymer network is ensured by a solubility test. It can be ensured that a copolymer network has been formed by placing the copolymer network in a solvent known to dissolve uncrosslinked copolymers of the same chemical nature. If the copolymer swells instead of dissolving, those skilled in the art know that a network has been formed. The figure 3 illustrates this solubility test.

The term “crosslinkable” means a copolymer capable of being crosslinked.

By “reversibly crosslinked” is meant a crosslinked copolymer the bridges of which are formed by a reversible chemical reaction. The reversible chemical reaction can move in one direction or another, causing a change in the structure of the polymer network. The copolymer can pass from an initial uncrosslinked state to a crosslinked state (three-dimensional network of copolymers) and from a crosslinked state to an initial uncrosslinked state. In the context of the present invention, the bridges which form between the chains of copolymers are labile. These bridges can form or be exchanged through a chemical reaction that is reversible. In the context of the present invention, the reversible chemical reaction is a transesterification reaction between diol functions of a random copolymer (copolymer A1) and boronic ester functions of a crosslinking agent (compound A2). The bridges formed are bonds of the boronic ester type. These boronic ester bonds are covalent and labile due to the reversibility of the transesterification reaction.

The term “thermoreversibly crosslinked” means a copolymer crosslinked by virtue of a reversible reaction, the movement of which in one direction or the other direction is controlled by temperature.

Unexpectedly, the Applicant has observed that the presence of exogenous compounds A4 in this composition of additives makes it possible to control the rate of association and dissociation between the polydiol A1 random copolymer and the compound A2, in particular the poly (ester random copolymer boronic).

The thermoreversible crosslinking mechanism of the additive composition of the invention in the presence of exogenous compounds A4 is shown schematically in figure 4 .

Unexpectedly, the Applicant has observed that at low temperature, the polydiol A1 copolymer (symbolized by the copolymer bearing A functions on the figure 4 ) is not or very little crosslinked by the boronic ester compounds A2 (symbolized by the compound carrying B functions on the figure 4 ). The boronic ester compounds A2 establish boronic ester bonds with the exogenous compound A4 (symbolized by the compound C on the figure 4 ) by transesterification reaction.

Polydiol A1 random copolymer is a heat-sensitive copolymer. When the temperature increases, the conformation in space of the chains of this copolymer is modified; the diol functions are made more accessible to association reactions. Thus, when the temperature increases, the diol functions of copolymer A1 react with the boronic ester functions of compound A2 by a transesterification reaction and release an A3 diol in situ. The polydiol A1 random copolymers and the A2 compounds comprising at least two boronic ester functions then bind together and can be exchanged. Depending on the functionality of the A1 polydiols and of the A2 compounds and depending on the composition of the mixtures, a gel may form in the medium, in particular when the medium is nonpolar.

When the temperature decreases again, the boronic ester bonds between the polydiol random copolymers A1 and the compounds A2 break, and where appropriate, the composition loses its gelled character. The compounds A2, in particular the poly (boronic ester) random copolymer, then establish boronic ester bonds by transesterification reaction with the exogenous compound A4 or with the diol compound A3 released in situ.

By controlling the degree of association of the polydiol A1 random copolymer and of the compound A2, in particular of the static poly (boronic ester) copolymer, the viscosity and the rheological behavior of this composition are modulated. The exogenous compound A4 makes it possible to modulate the viscosity of this composition as a function of the temperature and according to the desired use.

In a preferred embodiment of the invention, the exogenous compound A4 is of the same chemical nature as the diol compound A3 released in situ by transesterification reaction between the polydiol A1 random copolymer and the compound A2, in particular the poly (ester random copolymer boronic). The total amount of free diols present in said composition is strictly greater than the amount of diol compounds released in situ. The term “free diols” is understood to mean the diol functions which are capable of being able to form a chemical bond of the boronic ester type by transesterification reaction. For the purposes of the present application, the term “total amount of free diols” means the total number of diol functions capable of forming a chemical bond of boronic ester type by transesterification.

• i moles de composés exogènes diols A4 et
• j mol de copolymères statistiques polydiol A1,

The total quantity of free diols is always equal to the sum of the number of moles of exogenous compounds A4 diols and of the number (expressed in mol) of diol functions of the polydiol copolymer A1. In other words, if in the composition of additives we have:

• i moles of exogenous compounds A4 diols and
• j mol of polydiol A1 random copolymers,

the total amount of free diol will be at all times (therefore regardless of the degree of association between the polydiol A1 random copolymer and the A2 compound, in particular the A2 poly (boronic ester) random copolymer) = i + j * the average number of diols per random polymer chain A1 (unit: mol).

The quantity of diols released in situ in the context of the transesterification reactions between A1 and A2 is equal to the number of boronic ester functions linking the copolymers A1 and A2.

A person skilled in the art knows how to select the chemical structure and the quantity of exogenous compounds A4 which he adds to the composition of additives as a function of the molar percentage of boronic ester function of compound A2, in particular as a function of the poly (boronic ester random copolymer ), to modulate the rheological behavior of the composition.

The quantity of boronic ester bonds (or boronic ester bonds) which can be established between the polydiol A1 random copolymers and the A2 compounds, in particular the poly (boronic ester) random copolymers, is adjusted by a person skilled in the art by means of a appropriate selection of polydiol A1 random copolymer, A2 compound and mixture composition.

In addition, those skilled in the art know how to select the structure of compound A2, in particular of a poly (boronic ester) random copolymer, as a function of the structure of the A1 random copolymer. Preferably, when in the random copolymer A1 comprising at least one monomer M1 in which y = 1, then the compound A2 of general formula (III) or the copolymer A2 comprising at least one M3 monomer of formula (IV) will preferably be chosen with w ₁ = 1, w ₂ = 1 and t = 1, respectively.

Advantageously, the content of random copolymer A1 in the composition ranges from 0.1% to 99.5% by weight relative to the total weight of the additive composition, preferably ranges from 0.25% to 80% by weight per relative to the total weight of the additive composition, more preferably from 1% to 50% by weight relative to the total weight of the additive composition.

Advantageously, the content of compound A2, in particular of poly (boronic ester) random copolymer, in the composition ranges from 0.1% to 99.5% by weight relative to the total weight of the additive composition, preferably ranges from 0.25% to 80% by weight relative to the total weight of the additive composition, more preferably from 0.5% to 50% by weight relative to the total weight of the additive composition.

The molar percentage of exogenous compound A4 in the additive composition ranges from 0.025% to 5000%, preferably ranges from 0.1% to 1000%, more preferably from 0.5 to 500%, even more preferably from 1% to 150% relative to the boronic ester functions of compound A2, in particular of the poly (boronic ester) random copolymer. The molar percentage of exogenous compound A4 relative to the number of boronic ester functions of compound A2 is the ratio of the number of moles of exogenous compound A4 to the number of moles of boronic ester function of compound A2, the whole multiplied by one hundred. The number of moles of boronic ester function of compound A2 can be determined by a person skilled in the art by proton NMR analysis of compound A2, or by following the conversion into monomers during the synthesis of copolymer A2, when compound A2 is a poly (boronic ester) random copolymer.

The mass ratio (ratio A1 / A2) between the polydiol statistical compound A1 and the compound A2, in particular the poly (boronic ester) random copolymer, in the additive composition ranges from 0.005 to 200, preferably from 0.05 to 20 , even more preferably from 0.1 to 10, even more preferably from 0.2 to 5.

In one embodiment, the composition of the invention may further comprise at least one additive chosen from the group formed by thermoplastics, elastomers, thermoplastic elastomers, thermosetting polymers, pigments, dyes, fillers, plasticizers, fibers, antioxidants, lubricant additives, compatibilizers, anti-foaming agents, dispersant additives, adhesion promoters and stabilizers.

✔ Process for preparing the novel additive compositions of the invention

• prélever une quantité voulue d'une solution comprenant le copolymère statistique polydiol A1 tel que défini ci-dessus ;
• prélever une quantité voulue d'une solution comprenant le composé A2 tel que défini ci-dessus ; notamment une quantité voulue d'une solution comprenant le copolymère statistique poly(ester boronique) tel que défini précédemment ; et
• prélever une quantité voulue d'une solution comprenant le composé exogène A4 tel que défini ci-dessus
• mélanger les trois solutions prélevées, soit simultanément, soit séquentiellement, pour obtenir la composition de l'invention.

The novel additive compositions of the invention are prepared by means well known to those skilled in the art. For example, it is sufficient for those skilled in the art in particular to:

• withdrawing a desired amount of a solution comprising the polydiol A1 random copolymer as defined above;
• withdrawing a desired amount of a solution comprising compound A2 as defined above; in particular a desired amount of a solution comprising the poly (boronic ester) random copolymer as defined above; and
• withdraw a desired amount of a solution comprising the exogenous compound A4 as defined above
• mix the three solutions taken, either simultaneously or sequentially, to obtain the composition of the invention.

The order of addition of the compounds has no influence in the implementation of the process for preparing the additive composition.

• le pourcentage molaire de monomère M1 portant des fonctions diols dans le copolymère statistique polydiol A1 ;
• le pourcentage molaire de monomère M3 portant des fonctions ester boronique dans le copolymère statistique ester boronique A2 ;
• la longueur moyenne des chaînes latérales du copolymère statistique polydiol A1 ;
• la longueur moyenne des chaînes latérales du copolymère statistique ester boronique A2 ;
• la longueur du monomère M3 du copolymère statistique ester boronique A2 ;
• la longueur du composé diester boronique A2 ;
• le degré de polymérisation moyen en nombre des copolymères statistiques polydiol A1 et des copolymères statistiques ester boronique A2 ;
• le pourcentage massique du copolymère statistique polydiol A1 ;
• le pourcentage massique du composé diester boronique A2 ;
• le pourcentage massique du copolymère statistique ester boronique A2 ;
• la quantité molaire du composé exogène A4 par rapport aux fonctions ester boronique du composé A2, notamment du copolymère statistique poly(ester boronique),
• la nature chimique du composé exogène A4 ;
• le pourcentage molaire de composé exogène A4 ;

Those skilled in the art also know how to adjust the various parameters of the composition of the invention to obtain either a composition in which the polydiol A1 random copolymer and the compound A2, in particular the boronic ester random copolymer, are combined or a composition in which the Polydiol A1 random copolymer and compound A2, in particular the boronic ester random copolymer, are crosslinked and in order to modulate the degree of association or the degree of crosslinking for a given temperature of use. For example, those skilled in the art know how to adjust in particular:

• the molar percentage of monomer M1 carrying diol functions in the polydiol A1 random copolymer;
• the molar percentage of monomer M3 carrying boronic ester functions in the boronic ester random copolymer A2;
• the average length of the side chains of the polydiol A1 random copolymer;
• the average length of the side chains of the boronic ester A2 random copolymer;
• the length of monomer M3 of boronic ester random copolymer A2;
• the length of the boronic diester compound A2;
• the number-average degree of polymerization of the polydiol A1 random copolymers and the A2 boronic ester random copolymers;
• the percentage by weight of the polydiol A1 random copolymer;
• the percentage by mass of the boronic diester compound A2;
• the percentage by weight of the boronic ester A2 random copolymer;
• the molar amount of exogenous compound A4 relative to the boronic ester functions of compound A2, in particular of the poly (boronic ester) random copolymer,
• the chemical nature of the exogenous compound A4;
• the molar percentage of exogenous compound A4;

✔ Use of the new compositions of the invention

The compositions of the invention can be used in all media whose viscosity varies as a function of temperature. The compositions of the invention make it possible to thicken a fluid and to modulate the viscosity as a function of the temperature of use. The additive composition according to the invention can be used in fields as varied as improved oil recovery, the paper industry, paints, food additives, cosmetic or pharmaceutical formulation.

Lubricating composition according to the invention

• une huile lubrifiante
• un copolymère statistique polydiol A1 tel que défini précédemment,
• un copolymère statistique A2, tel que défini précédemment, comprenant au moins deux fonctions esters boroniques et pouvant s'associer avec ledit copolymère statistique polydiol A1 par au moins une réaction de transestérification,
• un composé exogène A4 choisi parmi les 1,2-diols et les 1,3-diols, et notamment tel que défini précédemment.

Another object of the present invention relates to a lubricating composition resulting from the mixture of at least:

• lubricating oil
• a polydiol A1 random copolymer as defined above,
• a statistical copolymer A2, as defined above, comprising at least two boronic ester functions and which can be combined with said polydiol A1 random copolymer by at least one transesterification reaction,
• an exogenous compound A4 chosen from 1,2-diols and 1,3-diols, and in particular as defined above.

The preferences and definitions described for the general formulas (I), (IA), (IB), (II-A), (II-B) also apply to the random copolymer A1 polydiol used in the lubricating compositions of the invention .

The preferences and definitions described for general formulas (IV) and (V) also apply to the boronic ester A2 random copolymer used in the lubricating compositions of the invention.

The lubricating compositions according to the invention have an inverted behavior with respect to a modification of the temperature compared to the behavior of the base oil and of the rheological additives of polymer type of the prior art and have the advantage that this rheological behavior can be modulated as a function of the temperature of use. Unlike the base oil which thins when the temperature increases, the compositions of the present invention have the advantage of thickening when the temperature increases. The formation of reversible covalent bonds makes it possible to (reversibly) increase the molar mass of the polymers and therefore limits the drop in the viscosity of the base oil at high temperatures. The additional addition of diol compounds makes it possible to control the rate of formation of these reversible bonds. Advantageously, the viscosity of the lubricating composition is thus controlled and depends less on temperature fluctuations. In addition, for a given temperature of use, it is possible to modulate the viscosity of the lubricating composition and its rheological behavior by adjusting the amount of diol compounds added to the lubricating composition.

∘ Lubricating oil

The term “oil” is understood to mean a fatty substance that is liquid at ambient temperature (25 ° C.) and atmospheric pressure (760 mmm of Hg evening 105 Pa).

By “lubricating oil” is meant an oil which attenuates the friction between two moving parts in order to facilitate the operation of these parts. Lubricating oils can be of natural, mineral or synthetic origin.

The lubricating oils of natural origin can be oils of vegetable or animal origin, preferably oils of vegetable origin such as rapeseed oil, sunflower oil, palm oil, olive oil. copra ...

Lubricating oils of mineral origin are of petroleum origin and are extracted from petroleum cuts resulting from the atmospheric and vacuum distillation of crude oil. Distillation can be followed by refining operations such as solvent extraction, dealphating, solvent dewaxing, hydrotreatment, hydrocracking, hydroisomerization, hydrofinishing, etc. cite paraffinic mineral base oils such as Bright Stock Solvent (BSS) oil, naphthenic mineral base oils, aromatic mineral oils, hydrorefined mineral bases with a viscosity index of approximately 100, mineral bases hydrocracked with a viscosity index between 120 and 130, hydroisomerized mineral bases with a viscosity index between 140 and 150.

• les huiles synthétiques à base d'hydrocarbures de synthèse telles que les polyalphaoléfines (PAO), les polyoléfines internes (PIO), les polybutènes et polyisobutènes (PIB), les dialkylbenènes, les polyphényles alkylés ;
• les huiles synthétiques à base d'esters telles que les esters de diacides, les esters de néopolyols ;
• les huiles synthétiques à base de polyglycols telles que les monoalkylèneglycols, les polyalkylèneglycols et les monoéthers de polyalkylèneglycols ;
• les huiles synthétiques à base d'ester-phosphates ;
• les huiles synthétiques à base de dérivés siliciés telles que les huiles silicones ou les polysiloxanes .

Lubricating oils of synthetic origin (or synthetic base) come, as their name suggests, from chemical synthesis such as the addition of a product to itself or polymerization, or the addition of a product to another such as esterification, alkylation, fluorination, etc., of components from petrochemicals, carbochemistry, and mineral chemistry such as: olefins, aromatics, alcohols, acids, halogenated compounds, phosphorus, silicas, etc. By way of illustration, we can cite:

• synthetic oils based on synthetic hydrocarbons such as polyalphaolefins (PAO), internal polyolefins (PIO), polybutenes and polyisobutenes (PIB), dialkylbenenes, alkylated polyphenyls;
• synthetic ester-based oils such as diacid esters, neopolyol esters;
• synthetic oils based on polyglycols such as monoalkylene glycols, polyalkylene glycols and polyalkylene glycol monoethers;
• synthetic oils based on ester-phosphates;
• synthetic oils based on silicon derivatives such as silicone oils or polysiloxanes.

The lubricating oils which can be used in the composition of the invention can be chosen from any of the oils of groups I to V specified in the guidelines of the API (Base Oil Interchangeability Guidelines of the American Petroleum Institute (API). ) (or their equivalents according to the ATIEL classification (Technical Association of the European Lubricants Industry) as summarized below: Content of saturated compounds * Sulfur content ** Viscosity index (VI) *** Group I Mineral oils <90% > 0.03% 80 ≤ VI <120 Group II Hydrocracked oils ≥ 90% ≤ 0.03% 80 ≤ VI <120 Group III Hydrocracked or hydroisomerized oils ≥ 90% ≤ 0.03% ≥ 120 Group IV (PAO) Polyalphaolefins Group V Esters and other bases not included in groups I to IV bases * measured according to ASTM D2007
** measured according to ASTM D2622, ASTM D4294, ASTM D4927 and ASTM D3120 standards
*** measured according to ASTM D2270

The compositions of the invention can comprise one or more lubricating oils. The lubricating oil or the lubricating oil mixture is the major ingredient in the lubricating composition. This is referred to as a lubricating base oil. By major ingredient is meant that the lubricating oil or the mixture of lubricating oils represents at least 51% by weight relative to the total weight of the composition.

Preferably, the lubricating oil or the mixture of lubricating oils represents at least 70% by weight relative to the total weight of the composition.

In one embodiment of the invention, the lubricating oil is selected from the group formed by oils of group I, group II, group III, group IV, group V of the API classification and one of their mixture. Preferably, the lubricating oil is chosen from the group formed by oils of group III, of group IV, of group V of the API classification and their mixture. Preferably, the lubricating oil is an oil of group III of the API classification. The lubricating oil has a kinematic viscosity at 100 ° C measured according to the ASTM D445 standard ranging from 2 to 150 cSt, preferably ranging from 5 to 15 cSt.

The lubricating oils can range from grade SAE 15 to grade SAE 250, and preferably from grade SAE 20W to grade SAE 50 (SAE stands for Society of Automotive Engineers

∘ Functional additives

In one embodiment, the composition of the invention may further comprise a functional additive chosen from the group formed by detergents, anti-wear additives, extreme pressure additives, antioxidants, polymers improving the viscosity index. , pour point improvers, defoamers, thickeners, anti-corrosion additives, dispersants, friction modifiers and mixtures thereof.

• soit chaque additif est ajouté isolément et séquentiellement dans la composition,
• soit l'ensemble des additifs est ajouté simultanément dans la composition, les additifs sont dans ce cas généralement disponibles sous forme d'un paquet, appelé paquet d'additifs.

The functional additive (s) which are added to the composition of the invention are chosen according to the end use of the lubricating composition. These additives can be introduced in two different ways:

• either each additive is added separately and sequentially in the composition,
• or all the additives are added simultaneously to the composition, the additives are in this case generally available in the form of a packet, called an additive packet.

The functional additive or the mixtures of functional additives, when they are present, represent from 0.1 to 10% by weight relative to the total weight of the composition.

✔ Detergents:

These additives reduce the formation of deposits on the surface of metal parts by dissolving the secondary products of oxidation and combustion. The detergents which can be used in the lubricating compositions according to the present invention are well known to those skilled in the art. The Detergents commonly used in the formulation of lubricating compositions are typically anionic compounds having a long lipophilic hydrocarbon chain and a hydrophilic head. The associated cation is typically a metal cation of an alkali or alkaline earth metal. The detergents are preferably chosen from alkali metal or alkaline earth metal salts of carboxylic acids, sulphonates, salicylates, naphthenates, as well as salts of phenates. The alkali metals and alkaline earth metals are preferably calcium, magnesium, sodium or barium. These metal salts may contain the metal in an approximately stoichiometric amount or in excess (in an amount greater than the stoichiometric amount). In the latter case, we are dealing with so-called overbased detergents. The excess metal providing the overbased character to the detergent is in the form of metal salts insoluble in oil, for example carbonate, hydroxide, oxalate, acetate, glutamate, preferably carbonate.

✔ Anti-wear additives and extreme pressure additives:

These additives protect the rubbing surfaces by forming a protective film adsorbed on these surfaces. There is a wide variety of antiwear and extreme pressure additives. By way of illustration, mention may be made of phosphosulfur additives such as metal alkylthiophosphates, in particular zinc alkylthiophosphates, and more specifically zinc dialkyldithiophosphates or ZnDTP, amine phosphates, polysulphides, in particular sulfur olefins and metal dithiocarbamates.

✔ Antioxidants:

These additives delay the degradation of the composition. The degradation of the composition can result in the formation of deposits, the presence of sludge, or an increase in the viscosity of the composition. Antioxidants act as free radical inhibitors or destroyers of hydroperoxides. Among the antioxidants commonly used are antioxidants of the phenolic or amine type.

✔ Anticorrosions:

These additives cover the surface with a film which prevents the access of oxygen to the surface of the metal. They can sometimes neutralize acids or certain chemicals to prevent corrosion of the metal. By way of illustration, mention may be made, for example, of dimercaptothiadiazole (DMTD), benzotriazoles, phosphites (capture of free sulfur).

✔ Polymers improving the viscosity index:

These additives make it possible to guarantee good resistance to cold and a minimum viscosity at high temperature of the composition. By way of illustration, mention may be made, for example, of polymeric esters, olefin copolymers (OCP), homopolymers or copolymers of styrene, butadiene or of isoprene and polymethacrylates (PMA).

✔ Pour point improvers:

These additives improve the cold behavior of the compositions, by slowing the formation of paraffin crystals. These are, for example, polymethacrylates of alkyl, polyacrylates, polyarylamides, polyalkylphenols, polyalkylnaphthalenes and alkylated polystyrenes.

✔ Defoamers:

These additives have the effect of countering the effect of detergents. By way of illustration, mention may be made of polymethylsiloxanes and polyacrylates.

✔ Thickeners:

Thickeners are additives used above all for industrial lubrication and make it possible to formulate lubricants of higher viscosity than lubricating compositions for engines. By way of illustration, mention may be made of polysiobutenes having a molar mass by weight of 10,000 to 100,000 g / mol.

✔ Dispersants:

These additives ensure the maintenance in suspension and the evacuation of the insoluble solid contaminants constituted by the secondary oxidation products which form during the use of the composition. By way of illustration, mention may be made, for example, of succinimides, PIB (polyisobutene) succinimides and Mannich bases.

✔ Friction modifiers;

These additives improve the coefficient of friction of the composition. By way of illustration, mention may be made of molybdenum dithiocarbamate, amines having at least one hydrocarbon chain of at least 16 carbon atoms, esters of fatty acids and of polyols such as esters of fatty acids and of glycerol, in particular glycerol monooleate.

✔ Process for preparing the lubricating compositions of the invention

• prélever une quantité voulue d'une solution comprenant le copolymère statistique polydiol A1 tel que défini ci-dessus, notamment celui résultant de la copolymérisation d'au moins un monomère de formule (I) avec au moins un monomère de formule (II-A) et au moins un monomère de formule (II-B) ;
• prélever une quantité voulue d'une solution comprenant le copolymère statistique A2 poly(ester boronique) tel que défini précédemment ;
• prélever une quantité voulue d'une solution comprenant le composé exogène A4 tel que défini ci-dessus
• mélanger soit simultanément, soit séquentiellement les trois solutions prélevées dans une huile de base lubrifiante, pour obtenir la composition lubrifiante de l'invention.

The lubricating compositions of the invention are prepared by means well known to those skilled in the art. For example, it is sufficient for those skilled in the art in particular to:

• take a desired amount of a solution comprising the polydiol A1 random copolymer as defined above, in particular that resulting from the copolymerization of at least one monomer of formula (I) with at least one monomer of formula (II-A) and at least one monomer of formula (II-B);
• withdrawing a desired amount of a solution comprising the A2 poly (boronic ester) random copolymer as defined above;
• withdraw a desired amount of a solution comprising the exogenous compound A4 as defined above
• mixing either simultaneously or sequentially the three solutions taken from a lubricating base oil, to obtain the lubricating composition of the invention.

The order of addition of the compounds has no influence on the implementation of the process for preparing the lubricating composition.

✔ Properties of the lubricating compositions according to the invention

The lubricating compositions of the invention result from the mixture of associative polymers which have the property of increasing the viscosity of the lubricating oil by associations, and in particular in certain cases by crosslinks. The lubricating compositions according to the invention have the advantage that these associations or crosslinking are thermoreversible and that the rate of association or crosslinking can be controlled by adding an additional diol compound.

Those skilled in the art know how to adjust the various parameters of the various constituents of the composition in order to obtain a lubricating composition whose viscosity increases when the temperature increases and to modulate its viscosity and its rheological behavior.

The quantity of boronic ester bonds (or boronic ester bond) which can be established between the polydiol random copolymers A1 and the compounds A2, in particular the boronic ester statistical copolymer A2, is adjusted by a person skilled in the art by means of an appropriate selection. of the polydiol A1 random copolymer, in particular that resulting from the copolymerization of at least one monomer of formula (I) with at least one monomer of formula (II-A) and at least one monomer of formula (II-B), of the compound A2, in particular the boronic ester random copolymer A2, of the exogenous compound A4, and in particular of the molar percentage of exogenous compound A4.

In addition, a person skilled in the art knows how to select the structure of compound A2, in particular of the boronic ester random copolymer, as a function of the structure of the A1 random copolymer, in particular that resulting from the copolymerization of at least one monomer of formula (I). with at least one monomer of formula (II-A) and at least one monomer of formula (II-B). Preferably, when in the random copolymer A1, in particular that resulting from the copolymerization of at least one monomer of formula (I) with at least one monomer of formula (II-A) and at least one monomer of formula (II-B) ), comprising at least one monomer M1 in which y = 1, then the compound A2 of general formula (III) or the copolymer A2 comprising at least one M3 monomer of formula (IV) will preferably be chosen with w ₁ = 1, w ₂ = 1 and t = 1, respectively.

• le pourcentage molaire de monomère M1 portant des fonctions diols dans le copolymère statistique polydiol A1 , notamment celui résultant de la copolymérisation d'au moins un monomère de formule (I) avec au moins un monomère de formule (II-A) et au moins un monomère de formule (II-B) ;
• le pourcentage molaire de monomère M3 portant des fonctions ester boronique dans le copolymère statistique ester boronique A2,
• la longueur moyenne des chaînes latérales du copolymère statistique polydiol A1, notamment celui résultant de la copolymérisation d'au moins un monomère de formule (I) avec au moins un monomère de formule (II-A) et au moins un monomère de formule (II-B) ;
• la longueur moyenne des chaînes latérales du copolymère statistique ester boronique A2,
• la longueur du monomère M3 du copolymère statistique ester boronique A2,
• le degré de polymérisation moyen des copolymères statistique polydiol A1, notamment celui résultant de la copolymérisation d'au moins un monomère de formule (I) avec au moins un monomère de formule (II-A) et au moins un monomère de formule (II-B), et des copolymères statistiques esters boroniques A2,
• le pourcentage massique du copolymère statistique polydiols A1, notamment celui résultant de la copolymérisation d'au moins un monomère de formule (I) avec au moins un monomère de formule (II-A) et au moins un monomère de formule (II-B),
• le pourcentage massique du copolymère statistique ester boronique A2,
• le pourcentage molaire de composé exogène A4 par rapport aux fonctions ester boronique du composé A2, notamment du copolymère statistique poly(ester boronique),

Moreover, those skilled in the art know how to adjust in particular:

• the molar percentage of monomer M1 carrying diol functions in the polydiol A1 random copolymer, in particular that resulting from the copolymerization of at least one monomer of formula (I) with at least one monomer of formula (II-A) and at least one monomer of formula (II-B);
• the molar percentage of monomer M3 carrying boronic ester functions in the statistical boronic ester copolymer A2,
• the average length of the side chains of the polydiol A1 random copolymer, in particular that resulting from the copolymerization of at least one monomer of formula (I) with at least one monomer of formula (II-A) and at least one monomer of formula (II -B);
• the average length of the side chains of the boronic ester A2 random copolymer,
• the length of the monomer M3 of the boronic ester statistical copolymer A2,
• the average degree of polymerization of the polydiol A1 random copolymers, in particular that resulting from the copolymerization of at least one monomer of formula (I) with at least one monomer of formula (II-A) and at least one monomer of formula (II- B), and statistical boronic ester copolymers A2,
• the percentage by weight of the polydiols A1 random copolymer, in particular that resulting from the copolymerization of at least one monomer of formula (I) with at least one monomer of formula (II-A) and at least one monomer of formula (II-B) ,
• the percentage by weight of the boronic ester A2 random copolymer,
• the molar percentage of exogenous compound A4 relative to the boronic ester functions of compound A2, in particular of the poly (boronic ester) random copolymer,

Advantageously, the content of random copolymer A1, in particular that resulting from the copolymerization of at least one monomer of formula (I) with at least one monomer of formula (II-A) and at least one monomer of formula (II-B) in the lubricating composition ranges from 0.25% to 20% by weight relative to the total weight of the lubricating composition, preferably from 1% to 10% by weight relative to the total weight of the lubricating composition.

Advantageously, the content of compound A2, in particular the content of boronic ester random copolymer, ranges from 0.25% to 20% by weight relative to the total weight of the lubricating composition, preferably from 0.5 to 10% by weight. weight relative to the total weight of the lubricating composition.

Preferably, the mass ratio (ratio A1 / A2) between the polydiol A1 random compound, in particular that resulting from the copolymerization of at least one monomer of formula (I) with at least one monomer of formula (II-A) and at least a monomer of formula (II-B), and compound A2, in particular the boronic ester random copolymer, ranges from 0.005 to 100, preferably from 0.05 to 20, even more preferably from 0.1 to 10, from more preferably from 0.2 to 5.

In one embodiment, the sum of the masses of the random copolymer A1, in particular that resulting from the copolymerization of at least one monomer of formula (I) with at least one monomer of formula (II-A) and at least one monomer of formula (II-A2), and of compound A2, in particular of the copolymer boronic ester statistic ranges from 0.5 to 20% relative to the total mass of the lubricating composition, preferably from 4% to 15% relative to the total mass of the lubricating composition and the mass of lubricating oil ranges from 60% to 99% relative to the total mass of the lubricating composition.

In one embodiment, the molar percentage of exogenous compound A4 in the lubricating composition ranges from 0.05% to 5000%, preferably ranges from 0.1% to 1000%, more preferably from 0.5% to 500. %, even more preferably from 1% to 150% relative to the boronic ester functions of compound A2, in particular of the poly (boronic ester) random copolymer.

• 0,5% à 20 % en poids d'au moins un copolymère statistique polydiol A1 tel que défini précédemment, par rapport au poids total de la composition lubrifiante ;
• 0,5% à 20 % en poids d'au moins d'au moins un composé A2 tel que défini précédemment, notamment en copolymère statistique ester boronique ; par rapport au poids total de la composition lubrifiante ; et
• 0,001% à 0,5 % en poids d'au moins un composé exogène A4 tel que défini précédemment, par rapport au poids total de la composition lubrifiante, et
• 60% à 99 % en poids d'au moins une huile lubrifiante tel que défini précédemment, par rapport au poids total de la composition lubrifiante.

In one embodiment, the lubricating composition of the invention results from the mixture of:

• 0.5% to 20% by weight of at least one polydiol A1 random copolymer as defined above, relative to the total weight of the lubricating composition;
• 0.5% to 20% by weight of at least one compound A2 as defined above, in particular as a boronic ester random copolymer; relative to the total weight of the lubricating composition; and
• 0.001% to 0.5% by weight of at least one exogenous compound A4 as defined above, relative to the total weight of the lubricating composition, and
• 60% to 99% by weight of at least one lubricating oil as defined above, relative to the total weight of the lubricating composition.

• 0,5% à 20 % en poids d'au moins un copolymère statistique polydiol A1 tel que défini précédemment, par rapport au poids total de la composition lubrifiante ;
• 0,5% à 20 % en poids d'au moins d'au moins un composé A2 tel que défini précédemment, notamment en copolymère statistique ester boronique ; par rapport au poids total de la composition lubrifiante ; et
• 0,001% à 0,5 % en poids d'au moins un composé exogène A4 tel que défini précédemment, par rapport au poids total de la composition lubrifiante, et
• 0,5% à 15 % en poids d'au moins un additif fonctionnel tel que défini précédemment, par rapport au poids total de la composition lubrifiante, et
• 60% à 99 % en poids d'au moins une huile lubrifiante tel que défini précédemment, par rapport au poids total de la composition lubrifiante.

Procédé pour moduler la viscosité d'une composition lubrifiante.In another embodiment, the lubricating composition of the invention results from the mixture of:

• 0.5% to 20% by weight of at least one polydiol A1 random copolymer as defined above, relative to the total weight of the lubricating composition;
• 0.5% to 20% by weight of at least one compound A2 as defined above, in particular as a boronic ester random copolymer; relative to the total weight of the lubricating composition; and
• 0.001% to 0.5% by weight of at least one exogenous compound A4 as defined above, relative to the total weight of the lubricating composition, and
• 0.5% to 15% by weight of at least one functional additive as defined above, relative to the total weight of the lubricating composition, and
• 60% to 99% by weight of at least one lubricating oil as defined above, relative to the total weight of the lubricating composition.

A method of modulating the viscosity of a lubricating composition.

• la fourniture d'une composition lubrifiante résultant du mélange d'au moins une huile lubrifiante, d'au moins un copolymère statistique polydiol A1 et d'au moins un copolymère statistique A2 comprenant au moins deux fonctions esters boroniques et pouvant s'associer avec ledit copolymère statistique polydiol A1 par au moins une réaction de transestérification,
• l'ajout dans ladite composition lubrifiante d'au moins un composé exogène A4 choisi parmi les 1,2-diols et les 1,3-diols.

Another object of the present invention is a method for modulating the viscosity of a lubricating composition, the method comprising at least:

• the supply of a lubricating composition resulting from the mixture of at least one lubricating oil, of at least one polydiol A1 random copolymer and at least one A2 random copolymer comprising at least two boronic ester functions and which can be combined with said polydiol A1 random copolymer by at least one transesterification reaction,
• the addition to said lubricating composition of at least one exogenous compound A4 chosen from 1,2-diols and 1,3-diols.

For the purposes of the present invention, the term “modulating the viscosity of a lubricating composition” means an adaptation of the viscosity at a given temperature as a function of the use of the lubricating composition. This is obtained by adding an exogenous compound A4 as defined above. This compound makes it possible to control the rate of association and crosslinking of the two copolymers, polydiol A1 and poly (boronic ester) A2.

avec :

• w₃ un nombre entier égal à 0 ou 1 ;
• R₁₄ et R₁₅ identiques ou différents choisis parmi le groupe formé par l'hydrogène et un groupe hydrocarboné ayant de 1 à 24 atomes de carbone.

Preferably, these 1,2-diols or 1,3 diols have the general formula (VI):

with :

• w ₃ an integer equal to 0 or 1;
• R ₁₄ and R ₁₅ identical or different selected from the group formed by hydrogen and a hydrocarbon group having from 1 to 24 carbon atoms.

• w₃ est un nombre entier égal à 0 ou 1 ;
• R₁₄ et R₁₅ sont différents, l'un des groupes R₁₄ ou R₁₅ est H et l'autre groupe R₁₄ ou R₁₅ est une chaîne hydrocarbonée, de préférence un groupe alkyle linéaire, ayant de 1 à 24 atomes de carbone, de préférence entre 4 et 18 atomes de carbone, de préférence entre 6 et 12 atomes de carbone.

In one embodiment, these 1,2-diols or 1,3 diols have the general formula (VI) in which:

• w ₃ is an integer equal to 0 or 1;
• R ₁₄ and R ₁₅ are different, one of the groups R ₁₄ or R ₁₅ is H and the other group R ₁₄ or R ₁₅ is a hydrocarbon chain, preferably a linear alkyl group, having from 1 to 24 carbon atoms , preferably between 4 and 18 carbon atoms, preferably between 6 and 12 carbon atoms.

Autres objet selon l'invention.The definitions and preferences relating to lubricating oils, to random copolymers A1, in particular that resulting from the copolymerization of at least one monomer of formula (I) with at least one monomer of formula (II-A) and at least one monomer of formula (II-B), to the boronic ester random copolymer A2 and to the exogenous compound A4 also apply to the processes for modulating the viscosity of a lubricating composition.

Other object according to the invention.

Another object of the present invention is the use of the lubricating composition as defined above for lubricating a mechanical part.

In the remainder of the description, the percentages are expressed by weight relative to the total weight of the lubricating composition.

The compositions of the invention can be used for lubricating the surfaces of parts which are conventionally found in an engine such as the piston system, segments, liners.

• 97% à 99,98% en poids d'une huile lubrifiante, et
• 0,1% à 3% en poids d'au moins copolymère statistique A1 tel que défini précédemment, notamment celui résultant de la copolymérisation d'au moins un monomère de formule (I) avec au moins un monomère de formule (II-A) et au moins un monomère de formule (II-B), d'au moins un copolymère statistique ester boronique A2 tel que défini précédemment ; et
• 0,001% à 0,1% en poids au moins un composé exogène A4 tel que défini précédemment ; la composition ayant une viscosité cinématique à 100°C mesurée selon la norme ASTM D445 allant de 3,8 à 26,1 cSt ; les pourcentages en poids étant exprimé par rapport au poids total de ladite composition.

Thus another object of the present invention is a composition for lubricating at least one engine, said composition comprising, in particular consists essentially of, a composition resulting from the mixture of:

• 97% to 99.98% by weight of a lubricating oil, and
• 0.1% to 3% by weight of at least random copolymer A1 as defined above, in particular that resulting from the copolymerization of at least one monomer of formula (I) with at least one monomer of formula (II-A) and at least one monomer of formula (II-B), of at least one boronic ester A2 random copolymer as defined above; and
• 0.001% to 0.1% by weight at least one exogenous compound A4 as defined above; the composition having a kinematic viscosity at 100 ° C. measured according to the ASTM D445 standard ranging from 3.8 to 26.1 cSt; the percentages by weight being expressed relative to the total weight of said composition.

In a composition for lubricating at least one engine as defined above, the random copolymers A1, in particular that resulting from the copolymerization of at least one monomer of formula (I) with at least one monomer of formula (II-A) and at least one monomer of formula (II-B), and the boronic ester A2 random copolymers as defined above can combine and exchange thermoreversibly in the presence of the exogenous compound A4; but they do not form three-dimensional networks. They are not crosslinked.

In one embodiment, the composition for lubricating at least one engine further comprises at least one functional additive chosen from the group formed by detergents, anti-wear additives, extreme pressure additives, additional antioxidants, anti-corrosion additives, polymers improving the viscosity index, pour point improvers, defoamers, thickeners, dispersants, friction modifiers and mixtures thereof.

• 82% à 99% en poids d'une huile lubrifiante, et
• 0,1% à 3% en poids d'au moins copolymère statistique A1 tel que défini précédemment, notamment celui résultant de la copolymérisation d'au moins un monomère de formule (I) avec au moins un monomère de formule (II-A) et au moins un monomère de formule (II-B), d'au moins un copolymère statistique ester boronique A2 tel que défini précédemment ; et
• 0,001% à 0,1% en poids au moins un composé exogène A4 tel que défini précédemment ;
• 0,5 à 15% en poids d'au moins un additif fonctionnel choisi parmi le groupe formé par les détergents, les additifs anti-usure, les additifs extrême pression, les antioxydants supplémentaires, les additifs anticorrosion, les polymères améliorant l'indice de viscosité, les améliorants de point d'écoulement, les anti-mousse, les épaississants, les dispersants, les modificateurs de frottements et leurs mélanges ;

la composition ayant une viscosité cinématique à 100°C mesurée selon la norme ASTM D445 allant de 3,8 à 26,1 cSt ; les pourcentages en poids étant exprimé par rapport au poids total de ladite composition.In one embodiment of the invention, the composition for lubricating at least one engine, said composition comprising, in particular consists essentially of, a composition resulting from the mixture of:

• 82% to 99% by weight of a lubricating oil, and
• 0.1% to 3% by weight of at least random copolymer A1 as defined above, in particular that resulting from the copolymerization of at least one monomer of formula (I) with at least one monomer of formula (II-A) and at least one monomer of formula (II-B), at least one boronic ester random copolymer A2 as defined above; and
• 0.001% to 0.1% by weight at least one exogenous compound A4 as defined above;
• 0.5 to 15% by weight of at least one functional additive chosen from the group formed by detergents, anti-wear additives, extreme pressure additives, additional antioxidants, anti-corrosion additives, polymers improving the heat index. viscosity, pour point improvers, defoamers, thickeners, dispersants, friction modifiers and mixtures thereof;

the composition having a kinematic viscosity at 100 ° C. measured according to the ASTM D445 standard ranging from 3.8 to 26.1 cSt; the percentages by weight being expressed relative to the total weight of said composition.

The definitions and preferences relating to lubricating oils, to random copolymers A1, in particular that resulting from the copolymerization of at least one monomer of formula (I) with at least one monomer of formula (II-A) and at least one monomer of formula (II-B), to the boronic ester random copolymer A2 and to the exogenous compound A4 also apply to the compositions for lubricating at least one engine.

Another object of the present invention is a composition for lubricating at least one transmission, such as manual or automatic gearboxes.

• 85% à 99,49% en poids d'une huile lubrifiante, et
• 0,5% à 15% en poids d'au moins copolymère statistique A1 tel que défini précédemment, notamment celui résultant de la copolymérisation d'au moins un monomère de formule (I) avec au moins un monomère de formule (II-A) et au moins un monomère de formule (II-B), d'au moins un copolymère statistique ester boronique A2 tel que défini précédemment ; et
• 0,001% à 0,5% en poids au moins un composé exogène A4 tel que défini précédemment ; la composition ayant une viscosité cinématique à 100°C mesurée selon la norme ASTM D445 allant de 4,1 à 41 cSt, les pourcentages en poids étant exprimé par rapport au poids total de ladite composition.

Thus another subject of the present invention is a composition for lubricating at least one transmission, said composition comprising, in particular consists essentially of, a composition resulting from the mixture of:

• 85% to 99.49% by weight of a lubricating oil, and
• 0.5% to 15% by weight of at least random copolymer A1 as defined above, in particular that resulting from the copolymerization of at least one monomer of formula (I) with at least one monomer of formula (II-A) and at least one monomer of formula (II-B), of at least one boronic ester A2 random copolymer as defined above; and
• 0.001% to 0.5% by weight at least one exogenous compound A4 as defined above; the composition having a kinematic viscosity at 100 ° C. measured according to the ASTM D445 standard ranging from 4.1 to 41 cSt, the percentages by weight being expressed relative to the total weight of said composition.

In a composition for lubricating at least one transmission as defined above, the random copolymers A1, in particular that resulting from the copolymerization of at least one monomer of formula (I) with at least one monomer of formula (II-A) and at least one monomer of formula (II-B), and the boronic ester A2 random copolymers as defined above can combine and exchange thermoreversibly in the presence of exogenous compound A4; but they do not form three-dimensional networks. They are not crosslinked.

In one embodiment, the composition for lubricating at least one transmission further comprises at least one functional additive chosen from the group formed by detergents, anti-wear additives, extreme pressure additives, additional antioxidants, anti-corrosion additives, polymers improving the viscosity index, pour point improvers, antifoams, thickeners, dispersants, friction modifiers and mixtures thereof.

• 70% à 99,39% en poids d'une huile lubrifiante, et
• 0,5% à 15% en poids d'au moins copolymère statistique A1 tel que défini précédemment, notamment celui résultant de la copolymérisation d'au moins un monomère de formule (I) avec au moins un monomère de formule (II-A) et au moins un monomère de formule (II-B), d'au moins un copolymère statistique ester boronique A2 tel que défini précédemment ; et
• 0,001% à 0,5% en poids au moins un composé exogène A4 tel que défini précédemment ;
• 0,1% à 15% en poids d'au moins un additif fonctionnel choisi parmi le groupe formé par les détergents, les additifs anti-usure, les additifs extrême pression, les antioxydants supplémentaires, les additifs anticorrosion, les polymères améliorant l'indice de viscosité, les améliorants de point d'écoulement, les anti-mousses, les épaississants, les dispersants, les modificateurs de frottements et leurs mélanges ;

la composition ayant une viscosité cinématique à 100°C mesurée selon la norme ASTM D445 allant de 4,1 à 41 cSt les pourcentages en poids étant exprimé par rapport au poids total de ladite composition.In one embodiment of the invention, the composition for lubricating in order to lubricate at least one transmission, said composition comprising, in particular consists essentially of, a composition resulting from the mixture of:

• 70% to 99.39% by weight of a lubricating oil, and
• 0.5% to 15% by weight of at least random copolymer A1 as defined above, in particular that resulting from the copolymerization of at least one monomer of formula (I) with at least one monomer of formula (II-A) and at least one monomer of formula (II-B), of at least one boronic ester A2 random copolymer as defined above; and
• 0.001% to 0.5% by weight at least one exogenous compound A4 as defined above;
• 0.1% to 15% by weight of at least one functional additive chosen from the group formed by detergents, anti-wear additives, extreme pressure additives, additional antioxidants, anti-corrosion additives, polymers improving the index viscosity, pour point improvers, antifoams, thickeners, dispersants, friction modifiers and mixtures thereof;

the composition having a kinematic viscosity at 100 ° C. measured according to the ASTM D445 standard ranging from 4.1 to 41 cSt, the percentages by weight being expressed relative to the total weight of said composition.

The definitions and preferences relating to lubricating oils, to random copolymers A1, in particular that resulting from the copolymerization of at least one monomer of formula (I) with at least one monomer of formula (II-A) and at least one monomer of formula (II-B), to the boronic ester random copolymer A2 and to the exogenous compound A4 also apply to the compositions for lubricating at least one transmission.

The compositions of the invention can be used for engines or transmissions of light vehicles, heavy goods vehicles but also ships.

Another subject of the present invention is a method for lubricating at least one mechanical part, in particular at least one engine or at least one transmission, said method comprising a step in which said mechanical part is brought into contact with at least one composition. lubricant as defined above.

The definitions and preferences relating to lubricating oils, to random copolymers A1, in particular that resulting from the copolymerization of at least one monomer of formula (I) with at least one monomer of formula (II-A) and at least one monomer of formula (II-B), to the boronic ester random copolymer A2 and to the exogenous compound A4 also apply to the method of lubricating at least one mechanical part .

Another object of the present invention relates to the use of at least one compound chosen from 1,2-diols or 1,3 diols for modulating the viscosity of a lubricating composition, said lubricating composition resulting from the mixture of at least one lubricating oil, of at least one polydiol A1 random copolymer and at least one A2 random copolymer comprising at least two boronic ester functions and which can be combined with said polydiol A1 random copolymer by at least one transesterification reaction.

avec :

• w₃ un nombre entier égale à 0 ou 1 ;
• R₁₄ et R₁₅ identiques ou différents choisis parmi le groupe formé par l'hydrogène et un groupe hydrocarboné ayant de 1 à 24 atomes de carbone.

Preferably, these 1,2-diols or 1,3 diols have the general formula (VI):

with :

• w ₃ an integer equal to 0 or 1;
• R ₁₄ and R ₁₅ identical or different selected from the group formed by hydrogen and a hydrocarbon group having from 1 to 24 carbon atoms.

• w₃ est un nombre entier égal à 0 ou 1 ;
• R₁₄ et R₁₅ sont différents, l'un des groupes R₁₄ ou R₁₅ est H et l'autre groupe R₁₄ ou R₁₅ est une chaîne hydrocarbonée, de préférence un groupe alkyle linéaire, ayant de 1 à 24 atomes de carbone, de préférence entre 4 et 18 atomes de carbone, de préférence entre 6 et 12 atomes de carbone.

In one embodiment, these 1,2-diols or 1,3 diols have the general formula (VI) in which:

• w ₃ is an integer equal to 0 or 1;
• R ₁₄ and R ₁₅ are different, one of the groups R ₁₄ or R ₁₅ is H and the other group R ₁₄ or R ₁₅ is a hydrocarbon chain, preferably a linear alkyl group, having from 1 to 24 carbon atoms , preferably between 4 and 18 carbon atoms, preferably between 6 and 12 carbon atoms.

EXAMPLES

The following examples illustrate the invention without limiting it.

1 Synthesis of random copolymers A1 carrying a diol function ∘ 1.1: From a monomer carrying a diol function protected in the form of a ketal

In one embodiment, the random copolymer A1 of the invention is obtained according to the following reaction scheme:

1.1.1 Synthesis of the M1 monomer carrying a diol function protected in the form of a ketal

The synthesis of a methacrylate monomer carrying a diol function protected in the form of a ketal is carried out in two steps (steps 1 and 2 of reaction scheme 10) according to the protocol below:

1 ^st step:

42.1 g (314 mmol) of 1,2,6-hexane triol (1,2,6-HexTri) are introduced into an IL flask. 5.88 g of molecular sieve (4Â) are added followed by 570 mL of acetone. 5.01 g (26.3 mmol) of para-toluenesulfonic acid (pTSA) are then slowly added. The reaction medium is left under stirring for 24 hours at room temperature. 4.48 g (53.3 mmol) of NaHCO ₃ are then added. The reaction medium is left under stirring for 3 hours at room temperature before being filtered. The filtrate is then concentrated under vacuum using a rotary evaporator until a suspension of white crystals is obtained. 500 mL of water are then added to this suspension. The solution thus obtained is extracted with 4 × 300 mL of dichloromethane. The organic phases are combined and dried over MgSO ₄ . The solvent is then completely evaporated under vacuum at 25 ° C. using a rotary evaporator.

Step ^2:

The product thus obtained is then introduced into an IL flask surmounted by a bromine funnel. The glassware used having been previously dried overnight in an oven thermostatically controlled at 100 ° C. 500 mL of anhydrous dichloromethane are then introduced into the flask followed by 36.8 g (364 mmol) of triethylamine. A solution of 39.0 g (373 mmol) of methacryloyl chloride (MAC) in 50 mL of anhydrous dichloromethane is introduced into the dropping funnel. The flask is then placed in an ice bath to lower the temperature of the reaction medium to around 0 ° C. The methacryloyl chloride solution is then added dropwise with vigorous stirring. Once the addition of the methacryloyl chloride is complete, the reaction medium is left under stirring for 1 hour at 0 ° C., then 23 hours at room temperature. The reaction medium is then transferred to a 3 L Erlenmeyer flask and 1 L of dichloromethane is added. The organic phase is then washed successively with 4 × 300 mL of water, 6 × 300 mL of an aqueous solution of 0.5 M hydrochloric acid, 6 × 300 mL of a saturated aqueous solution of NaHCO ₃ and new 4 × 300 mL of water. The organic phase is dried over MgSO ₄ , filtered and then concentrated under vacuum using a rotary evaporator to give 64.9 g (yield of 85.3%) of protected diol monomer in the form of a light yellow liquid. the characteristics of which are as follows:
¹ H NMR (400 MHz, CDCl3) δ: 6.02 (singlet, 1H), 5.47 (singlet, 1H), 4.08 (triplet, J = 6.8 Hz, 2H), 4.05 to 3 , 98 (multiplet, 1H), 3.96 (doublet of doublets, J = 6Hz and J = 7.6Hz, 1H), 3.43 (doublet of doublet, J = 7.2Hz and J = 7, 2Hz, 1H), 1.86 (doublet of doublets, J = 1.2Hz and J = 1.6Hz, 3H), 1.69-1.33 (multiplet, 6H), 1.32 (singlet, 3H), 1.27 (singlet, 3H).

1.1.2 Synthesis of methacrylate copolymers bearing diol functions

• Copolymérisation de deux monomères méthacrylate d'alkyle avec un monomère méthacrylate porteur d'une fonction diol protégée sous forme de cétal ;
• Déprotection du copolymère.

The synthesis of methacrylate copolymers bearing diol functions is carried out in two steps (steps 3 and 4 of reaction scheme 10):

• Copolymerization of two alkyl methacrylate monomers with a methacrylate monomer bearing a diol function protected in the form of a ketal;
• Deprotection of the copolymer.

More precisely, the synthesis of the copolymer is carried out according to the following protocol:
10.5 g (31.0 mmol) of stearyl methacrylate (StMA), 4.76 g (18.7 mmol) of lauryl methacrylate (LMA), 3.07 g (12.7 mmol) of methacrylate carrier d 'a protected diol function in the form of a ketal obtained according to the protocol described in paragraph 1.1.1, 68.9 mg (0.253 mmol) of cumyl dithiobenzoate and 19.5 mL of anisole are introduced into a 100 mL Schlenk tube. The reaction medium is placed under stirring and 8.31 mg (0.0506 mmol) of azobisisobutyronitrile (AIBN) in solution in 85 μL of anisole are introduced into the Schlenk tube. The reaction medium is then degassed for 30 minutes by bubbling argon before being brought to 65 ° C. for a period of 16 hours. The Schlenk tube is placed in an ice bath to stop the polymerization, then the polymer is isolated by precipitation in methanol, filtration and drying under vacuum at 30 ° C. overnight.

A copolymer is thus obtained having a number-average molar mass ( M _n ) of 51,400 g / mol, a polydispersity index (Ip) of 1.20 and a number-average degree of polymerization (DP _n ) of 184. These values are respectively obtained by exclusion chromatography steric using tetrahydrofuran as eluent and polystyrene calibration and by monitoring the conversion to monomers during the copolymerization.

The deprotection of the copolymer is carried out according to the following protocol:
7.02 g of copolymer containing approximately 20% of protected diol function obtained previously are introduced into a 500 mL Erlenmeyer flask. 180 mL of dioxane are added and the reaction medium is placed under stirring at 30 ° C. 3 mL of a 1M aqueous hydrochloric acid solution and then 2.5 mL of a 35% mass hydrochloric acid aqueous solution are added dropwise. The reaction medium then becomes slightly opaque and 20 mL of THF are introduced to make the medium completely homogeneous and transparent. The reaction medium is then left under stirring at 40 ° C. for 48 hours. The copolymer is recovered by precipitation in methanol, filtration and drying under vacuum at 30 ° C. overnight.

A poly (alkyl methacrylate-co-alkyldiol methacrylate) copolymer is obtained containing approximately 20 mol% of M1 diol monomer units, and having an average length of the pendant alkyl chains of 13.8 carbon atoms.

2. Synthesis of the poly (alkyl methacrylate-comonomer boronic ester copolymer

The monomer is obtained according to the two-step protocol:
The first step is to synthesize a boronic acid and the second step is to obtain a boronic ester monomer.

1 ^first stage :

4-Carboxyphenylboronic acid (CPBA) (5.01 g; 30.2 mmol) is introduced into an IL beaker followed by 350 mL of acetone and the reaction medium is placed under stirring. 7.90 mL (439 mmol) of water are added dropwise until complete dissolution of 4-carboxyphenylboronic acid. The reaction medium is then transparent and homogeneous. The 1,2-propanediol (2.78 g; 36.6 mmol) is then slowly added, followed by an excess of magnesium sulfate in order to trap the water initially introduced as well as the water released by the condensation between the CPBA and 1,2 propanediol. The reaction medium is left under stirring for 1 hour at 25 ° C. before being filtered. The solvent is then removed from the filtrate by means of an evaporator. rotary. The product thus obtained and 85 mL of DMSO are introduced into a 250 mL flask. The reaction medium is placed under stirring and then after complete homogenization of the reaction medium, 8.33 g (60.3 mmol) of K ₂ CO ₃ are added. The 4- (chloromethyl) styrene (3.34 g; 21.9 mmol) is then slowly introduced into the flask. The reaction medium is then left under stirring at 50 ° C. for 16 hours. The reaction medium is transferred to a 2 L Erlenmeyer flask, then 900 ml of water are added. The aqueous phase is extracted with 8 × 150 mL of ethyl acetate. The organic phases are combined, then extracted with 3 × 250 mL of water. The organic phase is dried over MgSO ₄ and filtered. The solvent is removed from the filtrate by means of a rotary evaporator to give the boronic acid monomer (5.70 g; yield 92.2%) in the form of a white powder, the characteristics of which are as follows:
¹ H NMR (400 MHz, Cdc13) δ: 7.98 (doublet, J = 5.6 Hz, 4H), 7.49 (doublet, J = 4 Hz, 4H), 6.77 (doublet of doublets, J = 10.8Hz and J = 17.6Hz, 1H), 5.83 (doublet of doublet, J = 1.2Hz and J = 17.6Hz, 1H), 5.36 (singlet, 2H), 5.24 (doublet of doublets, J = 1.2Hz and J = 11.2Hz, 1H).

2 ^th stage :

The boronic acid monomer (5.7 g; 20.2 mmol) obtained during the first step and 500 mL of acetone are introduced into an IL Erlenmeyer flask. The reaction medium is placed under stirring and 2.6 ml (144 mmol) of water are added dropwise until complete dissolution of the boronic acid monomer. The reaction medium is then transparent and homogeneous. A solution of 1,2-dodecanediol (5.32 g; 26.3 mmol) in 50 mL of acetone is slowly added to the reaction medium, followed by an excess of magnesium sulfate in order to trap the water initially introduced thus than the water liberated by the condensation between the boronic acid monomer and 1,2-dodecanediol. After 3 hours with stirring at room temperature, the reaction medium is filtered. The solvent is then removed from the filtrate by means of a rotary evaporator to give 10.2 g of a mixture of boronic ester monomer and 1,2-dodecanediol in the form of a light yellow solid.

The characteristics are as follows:
¹ H NMR (400 MHz, CDCl3): Boronic ester monomer: δ: 8.06 (doublet, J = 8 Hz, 2H), 7.89 (doublet, J = 8 Hz, 2H), 7.51 (doublet, J = 4Hz, 4H), 6.78 (doublet of doublets, J = 8Hz and J = 16Hz, 1H), 5.84 (doublet of doublets, J = 1.2Hz and J = 17.6Hz , 1H), 5.38 (singlet, 2H), 5.26 (doublet of doublets, J = 1.2Hz & J = 11.2Hz, 1H), 4.69-4.60 (multiplet, 1H) , 4.49 (doublet of doublets, J = 8Hz and J = 9.2Hz, 1H), 3.99 (doublet of doublets, J = 7.2Hz and J = 9.2Hz, 1H), 1 , 78 - 1.34 (multiplet, 18H), 0.87 (triplet, J = 6.4Hz, 3H); 1,2-dodecanediol: δ: 3.61-3.30 (multiplet, about 1.62H), 1.78-1.34 (multiplet, about 9.72H), 0.87 (triplet, J = 6, 4 Hz, approximately 1.62H)

∘ 2.2 Synthesis of statistical copolymer A2 poly (alkyl methacrylate-co-monomer boronic ester)

The statistical copolymer A2 is obtained according to the following protocol:
2.09 g of a previously prepared boronic ester and 1,2-dodecanediol monomer mixture (containing 3.78 mmol of boronic ester monomer), 98.3 mg (0.361 mmol) of cumyl dithiobenzoate, 22.1 g (86 , 9 mmol) of lauryl methacrylate (LMA) and 26.5 mL of anisole are introduced into a 100 mL Schlenk tube. The reaction medium is placed under stirring and 11.9 mg (0.0722 mmol) of azobisisobutyronitrile (AIBN) in solution in 120 μL of anisole are introduced into the Schlenk tube. The reaction medium is then degassed for 30 minutes by bubbling argon before being brought to 65 ° C. for a period of 16 hours. The Schlenk tube is placed in an ice bath to stop the polymerization, then the polymer is isolated by precipitation in anhydrous acetone, filtration and drying under vacuum at 30 ° C. overnight.

avec m =0,96 et n=0,04.A copolymer is thus obtained having the following structure:

with m = 0.96 and n = 0.04.

The boronic ester copolymer obtained has a number-average molar mass ( M _n ) equal to 37,200 g / mol, a polydispersity index (Ip) equal to 1.24 and a number-average degree of polymerization (DP _n ) equal to 166. These values are respectively obtained by size exclusion chromatography using tetrahydrofuran as eluent and a polystyrene calibration and by monitoring the conversion into monomers during the copolymerization. Proton NMR analysis of the final copolymer gives a composition of 4 mol% of boronic ester monomer and 96% of lauryl methacrylate.

3. Rheological studies ∘ 3.1 Ingredients for the formulation of compositions A to H Lubricating base oil

• Sa viscosité cinématique à 40°C mesurée selon la norme ASTM D445 est de 19,57 cSt ;
• Sa viscosité cinématique mesurée à 100°C selon la norme ASTM D445 est de 4,23 cSt ;
• Son indice de viscosité mesuré selon la norme ASTM D2270 est de 122 ;
• Sa volatilité Noack en pourcentage poids, mesurée selon la norme DIN 51581 est de 14,5 ;
• Sont point flash (flash point en anglais) en degré Celsius mesuré selon la norme ASTM D92 est de 230°C ;
• Son point d'écoulement (pour point en anglais) en degré Celsius mesuré selon la norme ASTM D97 est de -15°C.

The lubricating base oil used in the compositions to be tested is an oil from group III of the API classification, marketed by SK under the name Yubase 4. It has the following characteristics. following features:

• Its kinematic viscosity at 40 ° C measured according to the ASTM D445 standard is 19.57 cSt;
• Its kinematic viscosity measured at 100 ° C. according to the ASTM D445 standard is 4.23 cSt;
• Its viscosity index measured according to the ASTM D2270 standard is 122;
• Its Noack volatility in weight percentage, measured according to DIN 51581 is 14.5;
• Are flash point in degrees Celsius measured according to ASTM D92 is 230 ° C;
• Its pour point (for point in English) in degrees Celsius measured according to standard ASTM D97 is -15 ° C.

Polydiol A-1 random copolymer

This copolymer comprises 20 mol% of monomers having diol functions. The average side chain length is 13.8 carbon atoms. Its number average molar mass is 51,400 g / mol. Its polydispersity index is 1.20. Its number-average degree of polymerization (DPn) is 184. The number-average molar mass and the polydispersity index are measured by size exclusion chromatography measurement using a polystyrene calibration. This copolymer is obtained by following the implementation of the protocol described in paragraph 1 above.

Boronic ester A-2 statistical copolymer:

This copolymer comprises 4 mol% of monomers having boronic ester functions. The average side chain length is greater than 12 carbon atoms. Its number average molar mass is 37,200 g / mol. Its polydispersity index is 1.24. Its number-average degree of polymerization (DPn) is 166. Its number-average molar mass and the polydispersity index are measured by measurement of size exclusion chromatography using a polystyrene calibration. This copolymer is obtained by implementing the protocol described in paragraph 2 above.

Compound A-4:

1,2-Docecanediol comes from the supplier TCI®.

∘ 3.2 Formulation of compositions for the study of viscosity Composition A (comparative) is obtained as follows :

It contains a 4.2% by mass solution of a polymethacrylate polymer in a lubricating base oil of group III of the API classification. The polymer has a number-average molar mass (Mn) equal to 106 00 g / mol, a polydispersity index (Ip) equal to 3.06, a number-average degree of polymerization of 466 and the average length of the pendant chains is 14 carbon atoms.

This polymethacrylate is used as an additive improving the viscosity index.

4.95 g of a formulation having a mass concentration of 42% of this polymethacrylate in a group III base oil and 44.6 g of group III base oil are introduced into a flask. The solution thus obtained is kept under stirring at 90 ° C. until complete dissolution of the polymethacrylate.

A 4.2% solution by mass of this polymethacrylate is obtained.

This composition is used as a reference for the study of viscosity. It represents the rheological behavior of the lubricating compositions marketed.

Composition B (comparative) is obtained as follows :

6.75 g of polydiol copolymer A-1 and 60.7 g of a group III base oil are introduced into a flask. The solution thus obtained is kept under stirring at 90 ° C. until complete dissolution of the polydiol A-1.

A 10% solution by mass of polydiol copolymer A-1 is obtained.

Composition C (comparative) is obtained as follows :

6 g of the solution at 10% by mass of polydiol copolymer A-1 in a group III base oil prepared previously are introduced into a flask. 0.596 g of poly (boronic ester) A-2 and 9.01 g of group III base oil are added to this solution. The solution thus obtained is kept under stirring at 90 ° C. until complete dissolution of the poly (boronic ester) A-2.

A 3.8% by mass solution of polydiol copolymer A-1 and 3.8% by mass of poly (boronic ester) copolymer A-2 is obtained.

Composition D (according to the invention) is obtained as follows:

7.95 g of composition C prepared above are introduced into a flask. 19.2 mg of a solution at 5% by mass of 1,2-dodecanediol (compound A-4) in a group III base oil are added to this solution. The solution thus obtained is kept under stirring at 90 ° C. for two hours.

A solution of 3.8% by mass of polydiol copolymer A-1, 3.8% by mass of poly (boronic ester) copolymer A-2 and 10% molar of free 1,2-dodecanediol (compound A-4) is obtained. relative to the boronic ester functions of the poly (boronic ester) copolymer A-2.

Composition E (according to the invention) is obtained as follows:

4.04 g of composition C prepared above are introduced into a flask. 97.6 mg of a solution at 5% by mass of 1,2-dodecanediol (compound A-4) in a group III base oil are added to this solution. The solution thus obtained is kept under stirring at 90 ° C. for two o'clock.

A solution of 3.8% by mass of polydiol copolymer A-1, 3.8% by mass of poly (boronic ester) copolymer A-2 and 100% by mass of free 1,2-dodecanediol (compound A-4) is obtained. relative to the boronic ester functions of the poly (boronic ester) copolymer A-2.

Composition F (comparative) is obtained as follows :

0.80 g of poly (boronic ester) A-2 copolymer and 7.21 g of a group III base oil are introduced into a flask. The solution thus obtained is kept under stirring at 90 ° C. until complete dissolution of the polymer.

A 10% solution by mass of poly (boronic ester) copolymer A-2 is obtained.

∘ 3.2 Formulation of compositions for the study of their elastic modulus and their viscous modulus Composition G (comparative) is obtained as follows :

0.416 g of polydiol A1 copolymer and 0.46 g of poly (boronic ester) A-2 copolymer, then 8.01 g of group III base oil are introduced into a flask. The solution thus obtained is kept under stirring at 90 ° C. until the polymers have completely dissolved.

A 4.7% by mass solution of polydiol copolymer A-1 and 5.2% by mass of poly (boronic ester) copolymer A-2 is obtained.

Composition H (according to the invention) is obtained as follows :

2.00 g of solution G are introduced into a flask. 40.5 mg of the solution at 5% by mass of 1,2-dodecanediol (compound A-4) are added. The solution thus obtained is kept under stirring at 90 ° C. for 2 hours.

A 4.7% by mass solution of polydiol copolymer A-1, 5.2% by mass of poly (boronic ester) copolymer A-2 and 66% molar of 1,2-dodecanediol relative to the boronic ester functions of the poly (boronic ester) copolymer A-2.

∘ 3.3 Apparatus and protocols for measuring viscosity

The rheological studies were carried out using a Couette MCR 501 rheometer with controlled stress from the company Anton Paar.

In the case of the polymer formulations which do not form gels in a base oil of group III over the temperature range of the study (compositions A to F), the rheology measurements were carried out using a cylindrical geometry of reference DG 26.7 The viscosity was measured as a function of the shear rate for a temperature range varying from 10 ° C to 110 ° C. For each temperature, the viscosity of the system was measured as a function of the speed shear rate from 0.01 to 1000 s ^-1 . The viscosity measurements as a function of the shear rate at T = 10 ° C, 20 ° C, 30 ° C, 50 ° C, 70 ° C, 90 ° C and 110 ° C were carried out (ranging from 10 ° C at 110 ° C) followed by further measurements at 10 ° C and / or 20 ° C in order to assess the reversibility of the systems. An average viscosity was then calculated for each temperature using the measurement points located on the same plate.

a été choisie pour représenter l'évolution de la viscosité du système en fonction de la température, car cette grandeur reflète directement la compensation à la perte de viscosité naturelle d'une huile de base de groupe III des systèmes polymères étudiés.The relative viscosity calculated according to the following formula $$\left({\eta }_{\mathit{relative}}=\frac{{\eta }_{\mathit{solution}}}{{\eta }_{\mathit{oil}\mathit{of}\mathit{based}}}\right)$$

was chosen to represent the change in the viscosity of the system as a function of temperature, because this quantity directly reflects the compensation for the loss of natural viscosity of a group III base oil of the polymer systems studied.

In the case of the polymer formulations which form gels in a base oil of group III over the temperature range of the study (compositions G and H), the rheology measurements were carried out using a cone-plane geometry of reference CP50 (diameter = 50 mm, angle 2 °). The elastic modulus and the viscous modulus were measured as a function of the temperature for a temperature range varying from 10 ° C to 110 ° C. The heating (and cooling) rate was set 0.003 ° C / s, the angular frequency was chosen at 1 rad / s with the strain rate of 1%.

∘ 3.4 Results obtained in rheology

The viscosity of compositions A to F was studied for a temperature range from 10 ° to 110 ° C. The relative viscosity of these compositions is illustrated in figures 5 and 6 . The polydiol A-1 random copolymer, alone in composition B, does not allow compensation for the loss of natural viscosity of the group III base oil. The same is true for the poly (boronic ester) copolymer A-2 when this copolymer is used alone in composition F.

When the polydiol random copolymer A-1 and the poly (boronic ester) copolymer A-2 are present together in the same lubricating composition (composition C), a compensation is observed for the loss of natural viscosity of the base oil of group III greater than that resulting from the addition of the polymethacylate polymer in the group III base oil (composition A).

When the composition (composition C) further comprises 10 mol% of 1,2-dodecanediol free (compound A-4) relative to the boronic ester functions of the poly (boronic ester) copolymer A-2 (composition D); a slight decrease in the relative viscosity is observed at low temperatures (temperatures below 45 ° C) while the compensation for the loss of hot viscosity is slightly greater than that of composition C which comprises the polydiol random copolymer A-1 and the poly (boronic ester) copolymer A-2.

When the composition (composition C) further comprises 100 mol% of free 1,2-dodecanediol (compound A-4) relative to the boronic ester functions of the poly (boronic ester) copolymer A-2 (composition E), it is observed a decrease in the relative viscosity at low temperatures (temperatures below 45 ° C). At higher temperatures, the composition resulting from the blend of polydiols A-1 random copolymer, A-2 poly (boronic ester) copolymer and 1,2-dodecanediol (compound A-4) compensates for the loss of viscosity of the oil base of group III in a manner comparable to that obtained with the polymethacrylate polymer in the base oil of group III (composition A). Thus, in the presence of 1,2-dodecanediol, the cold properties of composition E have been improved compared to those of composition C. In addition, composition E still retains the property of compensating for the loss of viscosity of the Group III base oil for high temperatures. 1,2-Dodecanediol therefore makes it possible to modify, as a function of temperature, the viscosity of a lubricating composition resulting from the mixture of at least one polydiol A-1 random copolymer and at least one A-2 poly (ester boronic) by controlling the rate of association of the chains of these two copolymers.

The rheological behavior of compositions G and H was studied as a function of temperature (hysteresis curve in FIGS. 7 and 8). These two compositions result from the mixture in a base oil of group III of the polydiol random copolymer A-1 and of the random copolymer A-2 poly (boronic ester). Composition H further comprises 1,2-dodecanediol (compound A-4).

The intersection of curves G ′ and G ″ illustrates the change in state of the compositions, that is to say the passage from a liquid state to a gelled state when the temperature increases and the passage from a gelled state to a liquid state when the temperature decreases.

For composition G (FIG. 7), it is observed that the temperature at which the composition changes from a liquid state to a gelled state is carried out between 95 ° C. and 100 ° C. At this temperature, the chains of copolymers A-1 and A-2 associate, exchange and form a three-dimensional crosslinked network. When the temperature is reduced, a new change of state is observed for a temperature between 65 ° and 70 ° C. The composition changes from a gelled state to a liquid state where the copolymer chains no longer associate with each other.

For composition H (FIG. 8), a shift in the value of the temperature at which the composition changes state is observed. Indeed, composition H gels for a temperature between 105 and 110 ° C and passes to a liquid state for a temperature between 70 ° C and 75 ° C. 1,2 dodecanediol (compound A-4) makes it possible to modulate the rheological behavior of composition H.

Claims (16)

1. Composition of additives resulting from mixing at least:

   - a polydiol random copolymer A1,

   - a random copolymer A2 comprising at least two boronic ester functions and able to associate with said polydiol random copolymer A1 by at least one transesterification reaction,

   - an exogenous compound A4 selected from the 1,2-diols and the 1,3-diols,

   wherein the weight ratio of the polydiol random copolymer A1 to the random copolymer A2 (A1/A2 ratio) ranges from 0.005 to 200,
   the molar percentage of exogenous compound A4 relative to the boronic ester functions of the random copolymer A2 ranges from 0.025 to 5000%,
   the random copolymer A1 results from the copolymerization:

   ▪ of at least one first monomer M1 of general formula (I):

   

   in which:

   - R₁ is selected from the group formed by -H, -CH₃, and -CH₂-CH₃;

   - x is an integer ranging from 1 to 18; preferably from 2 to 18;

   - y is an integer equal to 0 or 1;

   - X₁ and X₂, identical or different, are selected from the group formed by hydrogen, tetrahydropyranyl, methyloxymethyl, tert-butyl, benzyl, trimethylsilyl and t-butyl dimethylsilyl;
   or

   - X₁ and X₂ form, with the oxygen atoms, a bridge of the following formula

   

   in which:

   - the stars (*) represent the bonds to the oxygen atoms,

   - R'₂ and R"₂, identical or different, are selected from the group formed by hydrogen and a C₁-C₁₁ alkyl, preferably methyl;
   or

   - X₁ and X₂ form, with the oxygen atoms, a boronic ester of the following formula:

   

   in which:

   - the stars (*) represent the bonds to the oxygen atoms,

   - R'"₂ is selected from the group formed by a C₆-C₁₈ aryl, a C₇-C₁₈ aralkyl and C₂-C₁₈ alkyl, preferably a C₆-C₁₈ aryl;

   ▪ with at least one second monomer M2 of general formula (II):

   

   in which:

   - R₂ is selected from the group formed by -H, -CH₃ and -CH₂-CH₃,

   - R₃ is selected from the group formed by a C₆-C₁₈ aryl, a C₆-C₁₈ aryl substituted with an R'₃ group, -C(O)-O-R'₃; -O-R'₃, -S-R'₃ and -C(O)-N(H)-R'₃ with R'₃ a C₁-C₃₀ alkyl group,

   the molar percentage of monomer M1 of formula (I) in the random copolymer A1 ranging from 1 to 30%, and the molar percentage of monomer comprising boronic ester functions in random copolymer A2 ranging from 0.25 to 20%.
2. Composition of additives according to claim 1, wherein the random copolymer A1 results from the copolymerization of at least one monomer M1 with at least two monomers M2 having different groups R₃.
3. Composition of additives according to claim2, wherein one of the monomers M2 of the random copolymer A1 has the general formula (II-A):

   

   in which:

   - R₂ is selected from the group formed by -H, -CH₃ and -CH₂-CH₃,

   - R"₃ is a C₁-C₁₄ alkyl group,

   and the other monomer M2 of the random copolymer A1 has the general formula (II-B):

   

   in which:

   - R₂ is selected from the group formed by -H, -CH₃ and -CH₂-CH₃,

   - R'"₃ is a C₁₅-C₃₀ alkyl group.
4. Composition of additives according to any one of claims 1 to 3, wherein the random copolymer A1 has a molar percentage of monomer M1 of formula (I) in said copolymer ranging from 5 to 25%, more preferably ranging from 9 to 21%.
5. Composition of additives according to any one of claims 1 to 4, wherein the random copolymer A2 results from the copolymerization

   ▪ of at least one monomer M3 of formula (IV):

   

   in which:

   - t is an integer equal to 0 or 1;

   - u is an integer equal to 0 or 1;

   - M and R₈ are divalent binding groups, identical or different, selected from the group formed by a C₆-C₁₈ aryl, a C₇-C₂₄ aralkyl and a C₂-C₂₄ alkyl, preferably a C₆-C₁₈ aryl,

   - X is a function selected from the group formed by -O-C(O)-, -C(O)-O-, -C(O)-N(H)-, -N(H)-C(O)-, -S-, -N(H)-, -N(R'₄)- and -O- with R'₄ a hydrocarbon-containing chain comprising from 1 to 15 carbon atoms;

   - R₉ is selected from the group formed by -H, -CH₃ and -CH₂-CH₃;

   - R₁₀ and R₁₁, identical or different, are selected from the group formed by hydrogen and a hydrocarbon-containing group having from 1 to 24 carbon atoms, preferably between 4 and 18 carbon atoms, preferably between 6 and 14 carbon atoms;

   and wherein the chain formed by the linking together of the R₁₀, M, X and (R8)_u groups with u equal to 0 or 1 of the monomer of general formula (IV) of the random copolymer A2 has a total number of carbon atoms ranging from 8 to 38, preferably from 10 to 26,

   ▪ with at least one second monomer M4 of general formula (V):

   

   in which:

   - R₁₂ is selected from the group formed by -H, -CH₃ and -CH₂-CH₃,

   - R₁₃ is selected from the group formed by a C₆-C₁₈ aryl, a C₆-C₁₈ aryl substituted with an R'₁₃ group, -C(O)-O-R'₁₃; -O-R'₁₃, -S-R'₁₃ and -C(O)-N(H)-R'₁₃ with R'₁₃ a C₁-C₂₅ alkyl group.
6. Composition of additives according to claim 5, wherein the random copolymer A2 has a molar percentage of monomer of formula (IV) in said copolymer ranging from 1 to 10%.
7. Composition of additives according to any one of claims 1 to 6, in which the exogenous compound A4 has the general formula (VI):

   

   with:

   w₃ an integer equal to 0 or 1;

   R₁₄ and R₁₅, identical or different, selected from the group formed by hydrogen and a hydrocarbon-containing group having from 1 to 24 carbon atoms.
8. Composition of additives according to claim 7, in which the substituents R₁₀, R₁₁ and the value of the index (t) of the monomer of formula (IV) of the random copolymer A2 are identical respectively to the substituents R₁₄, R₁₅ and to the value of the index w₃ of the exogenous compound A4 of formula (VI).
9. Composition of additives according to claim 7, in which at least one of the substituents R₁₀, R₁₁ or the value of the index (t) of the monomer of formula (IV) of the random copolymer A2 is different respectively from the substituents R₁₄, R₁₅ or the value of the index w₃ of the exogenous compound A4 of formula (VI).
10. Composition of additives according to any one of claims 1 to 9, in which the weight ratio of the polydiol random copolymer A1 to the random copolymer A2 (A1/A2 ratio) ranges from 0.05 to 20, more preferably from 0.1 to 10, even more preferably from 0.2 to 5.
11. Lubricant composition resulting from mixing at least:

    - a lubricating oil; and

    - a composition of additives defined according to any one of claims 1 to 10.
12. Lubricant composition according to claim 11, in which the weight ratio of the random copolymer A1 to the random copolymer A2 (A1/A2 ratio) ranges from 0.005 to 100, preferably from 0.05 to 20, even more preferably from 0.1 to 10, even more preferably from 0.2 to 5.
13. Lubricant composition according to claim 11 or claim 12, wherein the molar percentage of exogenous compound A4 relative to the boronic ester functions of the random copolymer A2 ranges from 0.05 to 5000%, preferably ranges from 0.1% to 1000%, even more preferably from 0.5% to 500%, even more preferably from 1% to 150%.
14. Lubricant composition according to any one of claims 11 to 13, resulting from additionally mixing a functional additive selected from the group formed by the detergents, antiwear additives, extreme pressure additives, additional antioxidants, viscosity index improving polymers, pour point improvers, antifoaming agents, anticorrosion additives, thickeners, dispersants, friction modifiers and mixtures thereof.
15. Process for modulating the viscosity of a lubricant composition, the process comprising at least:

    - supplying a lubricant composition resulting from mixing at least one lubricating oil, at least one polydiol random copolymer A1 and at least one random copolymer A2 comprising at least two boronic ester functions and able to associate with said polydiol random copolymer A1 by at least one transesterification reaction,

    - adding, to said lubricant composition, at least one exogenous compound A4 selected from the 1,2-diols and the 1,3-diols,

    wherein the weight ratio of the polydiol random copolymer A1 to the random copolymer A2 (A1/A2 ratio) ranges from 0.005 to 200,
    the molar percentage of exogenous compound A4 relative to the boronic ester functions of the random copolymer A2 ranges from 0.025 to 5000%,
    the random copolymer A1 results from the copolymerization:

    ▪ of at least one first monomer M1 of general formula (I):

    

    in which:

    - R₁ is selected from the group formed by -H, -CH₃, and -CH₂-CH₃;

    - x is an integer ranging from 1 to 18; preferably from 2 to 18;

    - y is an integer equal to 0 or 1;

    - X₁ and X₂, identical or different, are selected from the group formed by hydrogen, tetrahydropyranyl, methyloxymethyl, tert-butyl, benzyl, trimethylsilyl and t-butyl dimethylsilyl;
    or

    - X₁ and X₂ form, with the oxygen atoms, a bridge of the following formula

    

    in which:

    - the stars (*) represent the bonds to the oxygen atoms,

    - R'₂ and R"₂, identical or different, are selected from the group formed by hydrogen and a C₁-C₁₁ alkyl, preferably methyl;

    or

    - X₁ and X₂ form, with the oxygen atoms, a boronic ester of the following formula:

    

    in which:

    - the stars (*) represent the bonds to the oxygen atoms,

    - R'"₂ is selected from the group formed by a C₆-C₁₈ aryl, a C₇-C₁₈ aralkyl and C₂-C₁₈ alkyl, preferably a C₆-C₁₈ aryl;

    ▪ with at least one second monomer M2 of general formula (II):

    

    in which:

    - R₂ is selected from the group formed by -H, -CH₃ and -CH₂-CH₃,

    - R₃ is selected from the group formed by a C₆-C₁₈ aryl, a C₆-C₁₈ aryl substituted with an R'₃ group, -C(O)-O-R₃; -O-R'₃, -S-R'₃ and -C(O)-N(H)-R'₃ with R'₃ a C₁-C₃₀ alkyl group,

    the molar percentage of monomer M1 of formula (I) in the random copolymer A1 ranging from 1 to 30%, and the molar percentage of monomer comprising boronic ester functions in random copolymer A2 ranging from 0.25 to 20%.
16. Use of at least one compound selected from the 1,2-diols or the 1,3-diols for modulating the viscosity of a lubricant composition, said lubricant composition resulting from mixing at least one lubricating oil, at least one polydiol random copolymer A1 and at least one random copolymer A2 comprising at least two boronic ester functions and able to associate with said polydiol random copolymer A1 by at least one transesterification reaction,

    the weight ratio of the polydiol random copolymer A1 to the random copolymer A2 (A1/A2 ratio) ranges from 0.005 to 200,

    the molar percentage of the compound selected from the 1,2-diols or the 1,3-diols relative to the boronic ester functions of the random copolymer A2 ranges from 0.025 to 5000%,

    the random copolymer A1 results from the copolymerization:

    ▪ of at least one first monomer M1 of general formula (I):

    

    in which:

    - R₁ is selected from the group formed by -H, -CH₃, and -CH₂-CH₃;

    - x is an integer ranging from 1 to 18; preferably from 2 to 18;

    - y is an integer equal to 0 or 1;

    - X₁ and X₂, identical or different, are selected from the group formed by hydrogen, tetrahydropyranyl, methyloxymethyl, tert-butyl, benzyl, trimethylsilyl and t-butyl dimethylsilyl;
    or

    - X₁ and X₂ form, with the oxygen atoms, a bridge of the following formula

    

    in which:

    - the stars (*) represent the bonds to the oxygen atoms,

    - R'₂ and R"₂, identical or different, are selected from the group formed by hydrogen and a C₁-C₁₁ alkyl, preferably methyl;

    or

    - X₁ and X₂ form, with the oxygen atoms, a boronic ester of the following formula:

    

    in which:

    - the stars (*) represent the bonds to the oxygen atoms,

    - R'"₂ is selected from the group formed by a C₆-C₁₈ aryl, a C₇-C₁₈ aralkyl and C₂-C₁₈ alkyl, preferably a C₆-C₁₈ aryl;

    ▪ with at least one second monomer M2 of general formula (II):

    

    in which:

    - R₂ is selected from the group formed by -H, -CH₃ and -CH₂-CH₃,

    - R₃ is selected from the group formed by a C₆-C₁₈ aryl, a C₆-C₁₈ aryl substituted with an R'₃ group, -C(O)-O-R₃; -O-R'₃, -S-R'₃ and -C(O)-N(H)-R'₃ with R'₃ a C₁-C₃₀ alkyl group,

    the molar percentage of monomer M1 of formula (I) in the random copolymer A1 ranging from 1 to 30%, and the molar percentage of monomer comprising boronic ester functions in random copolymer A2 ranging from 0.25 to 20%.

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