Stabilizing agents for bituminous compositions

Description

1 / 21 “STABILIZING AGENTS FOR BITUMINOUS COMPOSITIONS”

[0001] The invention relates to the field of bituminous coatings, infrastructure, asphalt or aggregates, and more particularly to the field of bituminous emulsions. More particularly, the invention relates to additives present in bituminous coatings intended to stabilize and, more specifically, to limit, or even prevent, the sedimentation and / or creaming of particles present in bituminous compositions, typically bituminous emulsions.

[0002] These sedimentation and creaming phenomena are well known today, with sedimentation being the most frequently observed phenomenon, especially in bituminous emulsions. There are also known means to remedy this situation, most of which essentially consist of incorporating into these bituminous emulsions one or more agents that allow modifying the rheology and thus preventing the destabilization of the emulsion during storage, namely preventing sedimentation and / or creaming. These rheological agents are generally referred to as anti-sedimentation agents and anti-creaming agents by those skilled in the art.

[0003] The antisettling agents commonly used today in these applications are most often polymers, and among these, particular mention may be made of polymers or rheological agents, such as vegetable gums or gums obtained by biological fermentation, in particular xanthan gums or scleroglucans, which are, for example, described in document WO199106606 or in document US6451885. These polymers are most often present in the form of a powder or dispersion in a solvent.

[0004] Other rheological agents are also sometimes used, but these do not actually have an anti-settling and / or anti-creaming effect, and are referred to in these cases as thickening agents. Examples of such thickening agents are polyurethane thickeners, for example, described in document EP0534039, or celluloses, as described in documents WO200004096, US4492781, US6451885. Also found as thickening agents are Petition 870250091903, dated 08 / 10 / 2025, page 10 / 36 2 / 21 non-crosslinked cationic polymers, as described, for example, in documents Pat. US 4393155, Pat. US 4772647 and WO200100734. There are also other solutions, and one of the most commonly used solutions today is simply to add a salt, for example, sodium or potassium chloride, to the solution.

[0005] However, not all of these solutions are entirely satisfactory. Indeed, problems still persist with each of these existing solutions, including, for example, the stabilization of bituminous emulsions during storage, a problem that has not yet been fully resolved. One possible solution could be to increase the bitumen content. Another solution could be to increase the amount of emulsifier to reduce particle size. These two proposals, however, present a major disadvantage, which is the substantial additional cost generated by increasing the quantities of bitumen and / or emulsifier used.

[0006] The addition of thickening agents may also be considered in order to delay destabilization. However, these do not completely prevent destabilization. Furthermore, most thickeners that could be used are in solid form or as viscous liquids, which makes them difficult to handle, dose and incorporate into bituminous compositions.

[0007] Still other proposed solutions make use of anti-settling agents to prevent or at least limit destabilization, but these agents prove to be difficult to handle, either because they are in powder form or in the form of a dispersion in a solvent, thus requiring, in most cases, a redispersion step before use.

[0008] The objective of the present invention is to overcome the shortcomings of solutions proposed in the prior art and to propose bituminous emulsions that are stable or have improved stability and, more particularly, bituminous emulsions that do not settle or settle little or over time and / or that have no or little creaming effect over time. The inventors have now discovered that these objectives can be achieved wholly or partially thanks to the present invention. Other objectives will be presented throughout the Petition 870250091903, dated 08 / 10 / 2025, p. 11 / 36 3 / 21 description of the invention follows.

[0009] In the present description of the invention, it should be understood that all percentages and quantities in ppm are by weight and that all ranges of values ​​between ... and ... of ... to ... are inclusive limits, unless otherwise indicated.

[0010] Thus, a first subject of the invention relates to the use of a cross-linked cationic polymer and, preferably, a cross-linked acrylic polymer, as an anti-settling and / or anti-fouling agent in a bituminous composition.

[0011] In the present invention, the term bituminous composition means any composition comprising at least bitumen, optionally, but preferably water, optionally mineral particles and optionally one or more other additives well known to those skilled in the art. More specifically, the bituminous composition in the present invention is chosen from bitumens, asphalt mixtures, hot asphalt mixtures, warm asphalt mixtures, cold asphalt mixtures, bituminous emulsions and others, without this list being exhaustive. Preferably, the bituminous composition is a bituminous emulsion.

[0012] The bitumens used in the bituminous compositions of the present invention may be of any type well known to those skilled in the art and, in particular, those chosen from naphthenic bitumens, paraffinic bitumens, fused bitumens and other optionally modified, oxidized, recycled, synthetic or natural bitumens, as well as mixtures of two or more thereof.

[0013] The present invention thus relates to the use of at least one cross-linked cationic polymer used as a stabilizer for a bituminous composition and, more specifically, as an anti-settling agent and / or an anti-creaming agent for a bituminous composition. Among cross-linked cationic polymers, those in liquid form are preferred, and more preferably, those whose viscosity makes them easy to handle and, in particular, pumpable to facilitate their dosing and / or incorporation into bituminous compositions.

[0014] Cross-linked cationic polymers that can be used in the context Petition 870250091903, dated 08 / 10 / 2025, page 12 / 36 4 / 21 of the present invention are homopolymers or copolymers obtained by homopolymerization or copolymerization of at least one monomer containing, on the one hand, a cationic function, that is, cationic or capable of forming a cation, for example, and preferably an amine function, and, on the other hand, a polymerizable function and preferably a vinyl function, for example, and preferably chosen from among the vinyl, allyl, acryloyl, acrylamide, methacryloyl and methacrylamide functions.

[0015] Cross-linked cationic polymers, which can be used in the context of the present invention, are well known to those skilled in the art or easily prepared from known procedures available in the scientific literature and on the Internet.

[0016] According to a particularly preferred aspect, the crosslinked cationic polymers, which can be used in the context of the present invention, are homopolymers or copolymers obtained by homopolymerization or copolymerization, respectively, of at least one monomer containing, on the one hand, a pendant cationic function, for example, and preferably a pendant amine function, and, on the other hand, a polymerizable function, and preferably a vinyl function, for example, and preferably chosen from among the vinyl, allyl, acryloyl, acrylamide, methacryloyl and methacrylamide functions. More preferably, the crosslinked cationic polymeric polymers that can be used in the context of the present invention do not have a cationic function in the polymer chain.

[0017] Thus, and according to one embodiment, the crosslinked cationic polymers most particularly useful as antisettling agents according to the present invention are chosen from homo- or copolymers obtained by polymerization of at least one cationic monomer, chosen from monomers with a vinyl, allyl, acryloyl, acrylamide, methacryloyl and methacrylamide function, or their salts, optionally with one or more non-ionic or anionic monomers, optionally in the presence of a transfer agent, then or simultaneously, preferably crosslinking simultaneously by means of at least one crosslinking agent. Petition 870250091903, dated 08 / 10 / 2025, page 13 / 36 5 / 21

[0018] These cross-linked cationic polymers have been shown to be particularly effective as anti-settling agents in bituminous compositions and, in particular, in bituminous emulsions. These same cross-linked cationic polymers have also been shown, in some cases, to be particularly effective as anti-creaming agents in bituminous compositions and, in particular, in bituminous emulsions.

[0019] These cross-linked cationic polymers (homopolymers or copolymers) are most frequently and generally obtained according to the well-known polymerization processes known as inverse emulsion polymerization. The processes for obtaining such polymers are, for example, described in documents WO2005053748, US7452854, US20060094639 and US7687451.

[0020] More precisely, the crosslinked cationic polymers that can be used in the context of the present invention can be advantageously obtained by reverse emulsion polymerization of at least one water-soluble cationic monomer, preferably a water-soluble cationic monomer comprising at least one ethylenic unsaturation, as indicated above. The crosslinked cationic polymers usable in the context of the present invention can also comprise copolymers obtained by copolymerization, for example and preferably by reverse emulsion, of at least one water-soluble cationic monomer and at least one anionic and / or non-ionic monomer.

[0021] As indicated above, these polymerizations and copolymerizations are carried out upstream or are carried out alone and advantageously and more frequently simultaneously with a crosslinking operation, as is well known in the technical field.

[0022] According to a preferred embodiment, the cross-linked cationic polymers that can be used in the context of the present invention can be advantageously obtained by reverse emulsion polymerization of: a. at least one water-soluble cationic monomer, preferably a water-soluble ethylenically unsaturated cationic monomer, whose content is between 10% and 100%, relative to Petition 870250091903, dated 08 / 10 / 2025, page 14 / 36 6 / 21 composition by weight (a)+(b)+(d), preferably between 25% and 100%, b. at least one crosslinking agent whose content is between 2 ppm and 2000 ppm, relative to the composition by weight (a)+(b)+(d), preferably between 5 ppm and 100 ppm, advantageously between 100 ppm and 500 ppm, more preferably between 500 ppm and 2000 ppm, c. optionally between 0 and 50,000 ppm relative to the composition by weight (a)+(b)+(d) of at least one transfer agent, and d. optionally one or more anionic and / or non-ionic monomers.

[0023] Non-limiting examples of monomers capable of forming cross-linked cationic (co)polymers that can be used in the context of the present invention include dialkylaminoalkyl (meth)acrylates, dialkylaminoalkyl (meth)acrylamides, allylamine, methylallylamine, as well as their quaternary ammonium salts and their acid salts.

[0024] Non-limiting examples of crosslinking agents capable of forming the crosslinked cationic (co)polymers that can be used in the context of the present invention include bifunctional crosslinking agents, among which mention may be made of diallylamine, methyldiallylamine, divinylbenzene, tetraallylammonium chloride, allyl acrylates and methacrylates, glycol and polyglycol diacrylates and dimethacrylates, butadiene, 1,7-octadiene, allyl acrylamides, allyl methacrylamides, bisacrylamidoacetic acid, N,N'-methylene-bisacrylamide, polyallyl ether polyol, diacrylamide, cyanomethylacrylate, vinyloxyethyl acrylate, vinyloxyethyl methacrylate.Examples of di(meth)acrylates include polyalkylene glycol di(meth)acrylates, including polypropylene glycol di(meth)acrylate, ethylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, 1,3butylene glycol di(meth)acrylate, 1,6-butylene glycol, 1,6-hexanediol di(meth)acrylate, neopentylglycol di(meth)acrylate, 1,9-nonanediol di(meth)acrylate, but also 2,2'-bis-[4-(acryloxypropyloxyphenyl)]propane, 2,2'-bis-[4-(acryloxydiethoxyphenyl)]propane and zinc acrylate.

[0025] Other examples of crosslinking agents include tri(meth)acrylates, such as Petition 870250091903, dated 08 / 10 / 2025, page 15 / 36 7 / 21 such as trimethylolpropane tri(meth) acrylate (TMPTA), ethoxylated trimethylolpropane tri(meth) acrylate (such as, for example, (TMPTA 3OE), trimethylolethane tri(meth) acrylate, pentaerythritol tri(meth) acrylate and tetramethylolmethane tri(meth) acrylate.

[0026] Other examples of crosslinking agents also include tetra(meth)acrylate compounds, such as ditrimethylolpropane tetra(meth)acrylate, tetramethylolmethane tetra(meth)acrylate, pentaerythritol tetra(meth)acrylate, hexa(meth)acrylate compounds, such as dipentaerythritol hexa(meth)acrylate, penta(meth)acrylate compounds, such as dipentaerythritol penta(meth)acrylate, allylic compounds, such as allyl (meth)acrylate, diallyl phthalate, diallyl itaconate, diallyl fumarate, diallyl phthalate, diallyl maleate, polyallyl ethers of sucrose with 2 to 8 groups per molecule, polyallyl ethers of pentaerythritol, such as pentaerythritol diallyl ether, pentaerythritol triallyl ether and tetraallyl ether of Pentaerythritol, polyallyl ethers of trimethylolpropane, such as diallyltrimethylolpropane ether and triallyltrimethylolpropane ether. Other polyunsaturated compounds also include divinyl glycol, divinylbenzene, divinylcyclohexyl, and methylenebisacrylamide.

[0027] Mixtures of two or more of the above-mentioned crosslinking agents may, of course, be used in any proportions.

[0028] Among the transfer agents that may also be used, mention may be made, without limitation, of malic acid, lactic acid, formic acid, isopropanol, sodium hypophosphite, mercaptans, such as, for example, butylmercaptan, n-octylmercaptan, n-dodecylmercaptan, tert-dodecylmercaptan, mercaptoethanol and others.

[0029] Examples of nonionic monomers that can be copolymerized include, but are not limited to, acrylamide, methacrylamide, N-vinylpyrrolidone, vinyl acetate, vinyl alcohol, alkyl acrylates, alkyl methacrylates, (poly)alkylene glycol (meth)acrylates, allyl alcohol and others, as well as mixtures of two or more of them.

[0030] Among the anionic monomers that can be copolymerized, it can be Petition 870250091903, dated 08 / 10 / 2025, page 16 / 36 8 / 21 mention is made, not exhaustively, of acrylic acid, methacrylic acid, maleic anhydride, itaconic acid, crotonic acid, monomers with a sulfonic acid function, for example, 2-acrylamido-2-methylpropanesulfonic acid and its salts, as well as mixtures of two or more of the aforementioned anionic monomers.

[0031] Crosslinked acrylic polymer is understood to mean a crosslinked cationic polymer chosen from those described above, and which results from a homo- or copolymerization of at least one cationic monomer containing at least one vinylcarbonyl function, for example (meth)acryloyl or (meth)acrylamido.

[0032] As indicated above, preference is given to crosslinked cationic polymers and, among these, crosslinked acrylic polymers obtained by reverse emulsion polymerization and, more preferably, by reverse emulsion radical polymerization. In a preferred embodiment, the crosslinked cationic polymers that can be used in the context of the invention are in the form of a powder or dispersion in an aqueous phase, for example, at a content of about 10% to 50% by weight of polymer relative to the total weight of the dispersion in an aqueous phase.

[0033] The crosslinked cationic polymers that can be used in the context of the present invention are generally known as additives in cosmetic, pharmaceutical, veterinary and detergent formulations, and most frequently in textile softeners. According to another preferred embodiment, the preferred crosslinked cationic polymers are chosen from among cationic copolymers containing (meth)acrylate and (meth)acrylamide functional groups crosslinked with a bifunctional vinyl monomer, such as, for example, N,N'-methylene-bisacrylamide.

[0034] More specifically, non-limiting examples of commercially available crosslinked cationic polymers include Flosoft® FS 222 marketed by SNF, or Rheovis® FRC or Rheovis® CDE marketed by BASF. These polymers, or similar polymers, are described, for example, in the documents WO2005053748, US7452854, US20060094639 and US7687451 mentioned above.

[0035] It has been surprisingly discovered that cross-linked cationic polymers known in the prior art have stabilizing properties and, in Petition 870250091903, dated 08 / 10 / 2025, page 17 / 36 9 / 21 particularly, anti-settling properties in bituminous compositions and, in particular, in bituminous emulsions, which are quite surprising. The anti-settling properties of cross-linked cationic polymers that can be used in the context of the present invention are, in particular, measured in accordance with the standard NF EN 12847 Determination of the tendency to settle of bituminous emulsions of July 2009.

[0036] The amount of cross-linked cationic polymers described above effective in the use of the present invention can vary greatly depending on the nature of the bitumen, the bitumen content and the nature of the other components used in the bituminous composition, but also according to the intended applications. However, this amount is generally and most frequently between 0.01% and 10% in relation to the total amount of the bituminous composition and, according to a preferred aspect of the invention, the amount of cross-linked cationic polymers in the bitumen emulsion of the present invention is between 0.01% and 5%, more preferably between 0.01% and 3% in relation to the total amount of bituminous composition.

[0037] As indicated above, the bituminous composition may contain, in addition to the crosslinked cationic polymer(s) described above, one or more other additives, fillers, as well as various compounds, well known to those skilled in the art, among which, by way of non-limiting examples, surfactants, polymers, latex, mineral particles such as aggregates, sand and others may be mentioned.

[0038] Among the surfactants that may be present, mention may be made of surfactants and emulsifiers of any kind, well known to those skilled in the art, and preferably cationic surfactants and mixtures of two or more thereof, these mixtures preferably comprising at least one cationic surfactant, optionally in combination with one or more surfactants chosen from among non-ionic or amphoteric surfactants or quaternary ammonium compounds.

[0039] According to a particularly preferred embodiment, non-limiting examples of cationic surfactants include fatty polyamines, amidoamines Petition 870250091903, dated 08 / 10 / 2025, page 18 / 36 10 / 21 Fatty acids, fatty imidazolines, optionally ethoxylated, in particular compounds carrying hydrocarbon chains containing from 6 to 30 carbon atoms. Among these compounds, one can mention, for example, Dinoram® S, Emulsamine® L60 or Dinoram® SLB, sold by Arkema, as well as Indulin® R33, Indulin® R66 sold by Ingevity and Redicote® 404 or Redicote® EM 22 sold by Nouryon.

[0040] The bituminous composition may also comprise one or more other polymers, chosen, for example, from elastomers, in the form of a latex in the emulsion or as a simple mixture in the bitumen and preferably in the form of a latex. Latexes are natural or synthetic elastomers, natural latex being extracted from rubber trees, while synthetic latex is derived from petrochemicals. Among synthetic latexes, the most common is styrene-butadiene latex. When incorporated into bituminous compositions, latexes make it possible to significantly increase the elasticity of the mixtures, which can then respond to stronger constraints, particularly in terms of heavy traffic, extreme temperatures and others.

[0041] In yet another preferred aspect, the present invention relates to bituminous compositions that include a solvent. Solvent means a solvent or mixture of solvents selected from water and organic solvents. According to a particularly preferred aspect of the invention, the solvent is water. It may be provided, if necessary or desired, to use one or more organic solvents alone or with water. The organic solvents that may be used in the bituminous compositions of the invention are those that are soluble in water and preferably insoluble or moderately soluble with the bitumen included in said emulsion. In a particularly preferred manner, the solvent comprises water and, most advantageously, the solvent is water.

[0042] The bituminous composition of the present invention generally, and most often, has a pH between 1 and 3. This pH value can, in particular, be adjusted during the preparation of said composition by adding acid, as is well known to those skilled in the art. The acids that can be used are Petition 870250091903, dated 08 / 10 / 2025, page 19 / 36 11 / 21 mineral or organic acids, preferably mineral acids, in particular chosen from hydrochloric acid and phosphoric acid, hydrochloric acid being the most commonly and generally used acid in the technical field of bituminous emulsions.

[0043] The use according to the present invention is characterized by the fact that at least one crosslinked cationic polymer, stabilizing agent, i.e., anti-settling and / or anti-fouling agent, as just defined, is incorporated, according to any technique well known to those skilled in the art, for example, into bitumen or bituminous composition, using any appropriate means, for example, mixer, agitator, simple casting, etc.

[0044] According to another aspect, the present invention relates to a composition comprising at least bitumen and a crosslinked cationic polymer, preferably a crosslinked acrylic polymer. According to a preferred aspect, the composition of the invention comprises at least bitumen, as defined above, and between 0.01% and 10% of one or more crosslinked cationic polymer(s) as defined above, by weight relative to the total weight of said composition.

[0045] The composition of the invention may further comprise, as indicated above, one or more other additives, fillers and others, including surfactants, polymers, latex, solvents and others.

[0046] In the bituminous composition of the present invention, said at least one cross-linked cationic polymer and, preferably, said at least one cationic acrylic polymer, has anti-sedimentation and / or anti-fouling properties, that is, it prevents or at least significantly slows down the sedimentation and / or creaming, respectively, of the components present in said bituminous composition and, in particular, prevents or at least slows down the phase shift of bituminous compositions and, in particular, when the bituminous compositions are bituminous emulsions.

[0047] Thus, and according to yet another preferred aspect, the bitumen composition is a bituminous emulsion.

[0048] More specifically, the composition of the present invention is a Petition 870250091903, dated 08 / 10 / 2025, page 20 / 36 12 / 21 bituminous emulsion comprising: - between 30% and 75% bitumen, - between 0.01% and 10% of at least one cross-linked cationic polymer, - between 0.05% and 5% of at least one surfactant, preferably cationic, and - between 0% and 50% latex, - optionally solvent qsp 100%.

[0049] The bitumens used in the emulsion of the present invention may be of any type well known to those skilled in the art, as described above, and, more specifically, chosen from naphthenic bitumens, paraffinic bitumens, fused bitumens and other optionally modified, oxidized, synthetic or natural bitumens, as well as mixtures of two or more thereof.

[0050] The preferred cross-linked cationic polymers used as stabilizers and, in particular, as anti-settling and / or anti-creaming agents in the bitumen emulsions of the present invention are those described above and which are advantageously in liquid form and, more preferably, whose viscosity makes them easy to handle and, in particular, pumpable to facilitate their dosing and / or their incorporation into the bitumens.

[0051] It has been surprisingly discovered that the use, in bituminous compositions and more particularly in bitumen emulsions, of cross-linked cationic polymers known in the prior art has stabilizing properties and more particularly anti-settling and / or anti-creaming properties, which are quite surprising.

[0052] The amount of crosslinked cationic polymer(s) included in the emulsion of the present invention can vary greatly depending on the nature of the bitumen, the bitumen content and the nature of the other components used in said emulsion, in particular depending on the nature of the surfactant, preferably cationic, that performs the function of emulsifier.

[0053] As indicated above, the amount of cationic polymer(s) Petition 870250091903, dated 08 / 10 / 2025, page 21 / 36 13 / 21 crosslinked polymer(s) is comprised between 0.01% and 10% in relation to the total quantity of the bituminous composition and, in particular, of the bituminous emulsion and, according to a preferred aspect of the invention, the quantity of crosslinked cationic polymer(s) in the bitumen composition of the present invention is comprised between 0.01% and 5%, preferably even between 0.01% and 3% in relation to the total quantity of emulsion.

[0054] As indicated above, the composition according to the invention has a pH between 1 and 3, which pH can be adjusted by adding acid to said composition.

[0055] The bituminous composition of the invention, and in particular when it is a bituminous emulsion, may comprise one or more surfactants (or emulsifiers), as described above, and preferably one or more cationic surfactants, as well as optionally one or more latex, as described above.

[0056] The solvents possibly present in the bituminous composition of the invention are as described above and, preferably, when the bituminous composition is a bituminous emulsion, the solvent is water or a mixture of organic solvent(s) / water and, very advantageously, the solvent is water.

[0057] The bituminous compositions of the present invention can be prepared according to any method well known to those skilled in the art and, for example, by simple mixing of the different components of said emulsion. It has been observed that the anti-settling agent (the cross-linked cationic polymer) can be added either after the addition (after all other components) or in soap form, where the term soap refers to all water-soluble components, excluding in particular the bituminous phase.

[0058] Thus, and according to one embodiment, and in particular when the bituminous composition is a bituminous emulsion, it is prepared by first producing a soap by successively adding, with stirring, the surfactant, the solvent, which is usually water, and then the crosslinked cationic polymer. According to some preferred embodiments, the solvent may be heated before being added, so as to facilitate good homogenization with the others. Petition 870250091903, dated 08 / 10 / 2025, page 22 / 36 14 / 21 components.

[0059] Similarly, and according to another variant, it may be advantageous, especially when the soap is cloudy, to adjust the pH and, more particularly, to lower the pH of the soap, ideally to a pH value between 1 and 3, typically around 2, as indicated above. The bituminous emulsion is then produced by mixing the soap thus prepared with bitumen with agitation, for example, by means of a colloidal mill.

[0060] According to another embodiment, the composition of the invention, and in particular when it is a bituminous emulsion, the soap is prepared as described above, however without adding the cross-linked cationic polymer. The bituminous emulsion is produced by stirring, for example, with a colloidal mill, adding bitumen and soap that do not contain the cross-linked cationic polymer. The cross-linked cationic polymer is then added, still with stirring, to the bitumen composition thus prepared.

[0061] The bituminous composition, and in particular the bituminous emulsion of the present invention, has numerous advantages, among which we can mention very good stability and, in particular, very good storage stability, measured in accordance with the NF EN 12847 standard, i.e., at room temperature and for 7 days.

[0062] Furthermore, the bituminous composition, and in particular the bituminous emulsion of the present invention, allows and guarantees good, or even very good, application performance. In particular, the bitumen composition of the present invention does not result in a substantial modification of the rupture index, nor in a substantial modification of the flow viscosity. Another non-negligible advantage of the bitumen composition of the present invention is an improvement in the bitumen adhesion, particularly on certain aggregates, but without limitation, on aggregates of an acidic nature, such as, for example, and not limited to, quartz, granites, certain sandstones or diorites.

[0063] The following examples are presented as illustrations of the present invention and are in no way limited to the invention, the scope of which is protected. Petition 870250091903, dated 08 / 10 / 2025, p. 23 / 36 15 / 21 confirmed by the claims attached to this description. Examples

[0064] The study aims to evaluate the effectiveness of the claimed solutions. The testing and analysis methods used are described below.

[0065] The tendency to settle after seven days of storage is evaluated according to standard NF EN 12847 (July 2009), Determination of the tendency to settle of bituminous emulsions. The emulsions are placed in a 100 ml graduated cylinder. After 7 days of storage at room temperature without agitation, the water content is determined in the upper 10 ml and the lower 10 ml. The emulsion is considered stable if the difference in paste content between the two fractions is less than 10%.

[0066] The adhesion of bitumen to aggregate is determined according to a test adapted from standard NF EN 13614 (June 2011), Determination of the adhesion of bituminous emulsions by the water immersion test. A coating of a fraction of washed and dried Vignat (quartz) 6 / 10 granules is applied. After a maturation time of 16 to 24 hours at room temperature, the mixture is immersed in boiling water for 5 minutes. The percentage of bitumen remaining on the surface of the aggregates is evaluated according to the classification guide of the standard on which this test is based.

[0067] The rupture index is measured in accordance with standard NF EN 13075-1 “Bitumes and bituminous binders - Determination of rupture behavior Part 1: Determination of the rupture index of cationic bitumen emulsions, fine mineral particle method” (September 2002).

[0068] Viscosity (in Pa.s) was measured using an Anton Paar MCR 501 rheometer equipped with a 25 mm diameter planar geometry at an angular oscillation frequency of 10 rad / s, a strain amplitude of 1%, and a temperature of 25 °C.

[0069] Example 1: Addition of anti-settling agents in the aqueous phase, improved stability

[0070] Cationic bitumen emulsions with a low content of Petition 870250091903, dated 08 / 10 / 2025, page 24 / 36 16 / 21 bitumen, with the proportions indicated in Table 1 below. Dosages are given in kilograms (kg) for one ton of prepared emulsion.

[0071] Emulsion R1 is a reference emulsion that does not contain an antisettling agent, emulsions E1 and E2 are emulsions according to the invention, the additive is added to the aqueous phase, called soap. — Table 1 — Emulsion R1 E1 E2 Bituminous phase: 5 (30 kg) Bitumen 70 / 100 Total Grandpuits 500 500 500 Aqueous phase: 500 kg Surfactant Dinoram® S(1) Dinoram® S(1) Dinoram® S(1) 2 2 2 Acid HCl HCl HCl 2.1 1.9 2 Anti-sedimentation agent - Rheovis® CDE(2) Flosoft FS 222(3) 0 1 1 Water 495.9 495.1 495 (1) : Dinoram® S is a cationic emulsifying surfactant, marketed by Arkema, (2) : Rheovis® CDE is a cationic acrylic LDP polymer, marketed by BASF, (3) : Flosoft FS 222 is a cationic thickening polymer marketed by SNF.

[0072] The emulsions are all three prepared according to an identical protocol using an Emulbitume laboratory automatic mill. The properties of the emulsions obtained are presented in Table 2 below: Table 2 Emulsion R1 E1 E2 Petition 870250091903, dated 08 / 10 / 2025, page 25 / 36 17 / 21 Emulsion R1 E1 E2 pH of aqueous phase(4) 2 2 2 Homogeneity by sieving (5) 0 0.03 0.01 Laser particle size distribution - D50 (6) 3.5 μm 2.6 μm 2.5 μm Laser particle size distribution - D90 (7) 11.3 μm 8.6 μm 7.9 μm Tendency to sedimentation (8) 28.9 0.6 0.3 (4): according to standard NF EN 12850, (5): rejection at 500 μm, according to standard NF EN 1429, (6): D50 particle size measured with a laser particle size analyzer, (7): D90 particle size measured with a laser particle size analyzer, (8): after storage for 7 days, according to standard NF EN 12847.

[0073] This example shows a significantly reduced sedimentation tendency using the additives of the invention, resulting in a very strong improvement in emulsion stability. The particle sizes are only slightly modified (reduction in D50 and D90) and remain fully acceptable for the intended applications.

[0074] Example 2: Emulsion stabilization by adding an antisettling agent according to and not according to the invention.

[0075] Other cationic bitumen emulsions of the spreading type are produced. This second example allows comparing the effect of adding the anti-settling additives, as described in the invention, with a commercial additive that does not conform to the invention.

[0076] Emulsion R2 is another reference emulsion that does not contain an anti-settling agent; emulsions E3 and E4 are emulsions according to the invention, for which the additive is added to the soap. Emulsion EC1 is an emulsion produced with a commercial anti-settling agent that is not according to the invention and which has also been added to the soap.

[0077] The proportions of the various components of the emulsions studied are Petition 870250091903, dated 08 / 10 / 2025, page 26 / 36 18 / 21 presented in Table 3 below, where dosages are expressed in kilograms (kg) per ton of emulsion prepared. Table 3 Emulsion R2 E3 E4 EC1 Bituminous phase: 650 kg Bitumen 70 / 100 Total Grandpuits 650 650 650 650 Aqueous phase: 350 kg Surfactant Dinoram® S83(9) Dinoram® S83(9) Dinoram® S83(9) Dinoram® S83(9) 2 2 2 2 Acid HCl HCl HCl HCl 1.9 2.7 2.8 1.8 Anti-settling agent - Rheovis® CDE(2) Flosoft FS 222(3) Additive V100(10) 0 0.5 0.5 0.5 Water 346.1 344.8 344.7 345.7 (2) : Rheovis® CDE is a cationic acrylic LDP polymer, marketed by BASF, (3) : Flosoft FS 222 is a cationic thickening polymer marketed by SNF, (9) : Dinoram® S83 is a cationic emulsifying surfactant, marketed by Arkema, (10) : The V100 viscosity additive, marketed by Arkema, is a gum-type rheological additive that improves storage stability.

[0078] The emulsions are all prepared according to an identical protocol using an Emulbitume laboratory automatic mill. The properties of the emulsions obtained are presented in Table 4 below: Table 4 - Petition 870250091903, dated 08 / 10 / 2025, page 27 / 36 19 / 21 Emulsion R2 E3 E4 EC1 pH of aqueous phase(4) 2 1.5 1.5 2 Homogeneity by sieving (5) 0.04 0.02 0.03 0.06 Viscosity (10 rad / s) 0.5 Pa.s 0.6 Pa.s 0.85 Pa.s 8.5 Pa.s Laser particle size distribution - D50 (6) 5 μm 4.6 μm 4.6 μm 4.7 μm Laser particle size distribution - D90 (7) 16 μm 15 μm 14.7 μm 15.1 μm Tendency to sedimentation (8) 14.6 2.33 1.67 0.04 (4): in accordance with standard NF EN 12850, (5): rejection at 500 μm, in accordance with standard NF EN 1429, (6): D50 particle size measured with a laser particle size analyzer, (7): D90 particle size measured with a laser particle size analyzer, (8): after storage for 7 days, in accordance with standard NF EN 12847.

[0079] This example shows a very strong improvement in emulsion stability with the additives of the invention and with the commercial additive that does not conform to the invention (gum base).

[0080] Unlike the additive that does not conform to the invention, the additives described in the invention also have the advantage of not modifying the viscosity of the emulsion, whereas the EC1 emulsion is 17 times more viscous than the reference emulsion. Furthermore, foam formation is observed for this emulsion, which is not acceptable from an industrial point of view. Example 3: Comparison between addition in the aqueous phase and after addition.

[0081] Other cationic bitumen emulsions of the spreading type are produced. This example compares the effect of adding anti-settling additives in the aqueous phase or after addition to the emulsion.

[0082] Cationic bitumen emulsions with a low content of Petition 870250091903, dated 08 / 10 / 2025, pages 28 / 36 20 / 21 bitumen, with the proportions indicated in Table 5 below. Dosages are given in kilograms (kg) for one ton of prepared emulsion.

[0083] Emulsion R3 is a reference emulsion that does not contain an anti-settling agent; emulsions E5 and E6 are emulsions according to the invention. For E5, the anti-settling agent is added to the soap, while for E6 it is added as a post-addition to the emulsion. Table 5 Emulsion R3 E5 E6 Bituminous phase: 630 kg Bitumen 70 / 100 Total Grandpuits 500 500 500 Aqueous phase: 370 kg Surfactant Dinoram® S83(9) Dinoram® S83(9) Dinoram® S83(9) 2 2 2 Acid HCl HCl HCl 1.8 1.9 1.8 Anti-settling agent - Flosoft FS 222(3) added to soap Flosoft FS 222(3) in post-addition 0 0.5 0.5 Water 366.2 365.6 365.7 (3) : Flosoft FS 222 is a cationic thickening polymer marketed by SNF, (9) : Dinoram® S83 is a cationic emulsifying surfactant, marketed by Arkema,

[0084] The emulsions are all prepared according to an identical protocol using an Emulbitume laboratory automatic mill. The properties of the emulsions obtained are presented in Table 6 below: Table 6 - Petition 870250091903, dated 08 / 10 / 2025, p. 29 / 36 21 / 21 Emulsion R3 E5 E6 pH of aqueous phase(4) 2 2 2 Viscosity (11) 7 s 7 s 9 s Breaking index(12) 102 103 105 Bitumen adhesiveness(13) 50 75 75 (4): in accordance with standard NF EN 12850, (11): flow viscosity 4 μm at 40°C, in accordance with standard NF EN 12846, (12): measured in accordance with standard NF EN 13075-1, (13): bitumen adhesion to granules measured in accordance with the operational procedure adapted from standard NF EN 13614, as indicated above.

[0085] This example shows that the addition of the additive according to the invention, whether in the aqueous phase or after the addition, does not influence the breaking properties or viscosity of the emulsion. These properties are of great importance for the use of bituminous emulsions such as those made in the example, which are intended for spreading. In both cases (direct addition to the soap or post-addition), a clear improvement in the adhesion of the bitumen to the aggregate is noted in the presence of the additive as described in the invention. Petition 870250091903, dated 08 / 10 / 2025, pages 30 / 36

Claims

1 / 3 CLAIMS 1. Use of a cross-linked cationic polymer, characterized in that such use is as an anti-settling agent and / or anti-creaming agent in a bituminous composition.

2. Use, according to claim 1, characterized in that the bituminous composition is chosen from bitumens, asphalt mixtures, hot asphalt mixtures, warm asphalt mixtures, cold asphalt mixtures, bituminous emulsions, and wherein, preferably, the bituminous composition is a bituminous emulsion.

3. Use, according to claim 1 or claim 2, characterized in that the bitumen of the bituminous composition is chosen from naphthenic bitumens, paraffinic bitumens, optionally modified, oxidized, recycled, synthetic or natural fused bitumens, as well as mixtures of two or more thereof.

4. Use, according to any of the preceding claims, characterized in that the crosslinked polymer is chosen from homo- or copolymers obtained by polymerization of at least one cationic monomer, chosen from monomers with a vinyl, allyl, acryloyl, acrylamido, methacryloyl and methacrylamido function, or their salts, optionally with one or more non-ionic or anionic monomers, optionally in the presence of a transfer agent, after or simultaneously with, preferably simultaneously with crosslinking by means of at least one crosslinking agent.

5. Use, according to any of the preceding claims, characterized in that the crosslinked cationic polymer is obtained by reverse emulsion polymerization of: a. at least one water-soluble cationic monomer, preferably a water-soluble ethylenically unsaturated cationic monomer, the content of which is between 10% and 100%, relative to the weight composition (a)+(b)+(d), preferably between 25% and 100%, b. at least one crosslinking agent the content of which is between 2 ppm and Petition 870250091903, dated 08 / 10 / 2025, page. 31 / 36 2 / 3 2000 ppm, relative to the weight composition (a)+(b)+(d), preferably between 5 ppm and 100 ppm, advantageously between 100 ppm and 500 ppm, more preferably between 500 ppm and 2000 ppm, c. optionally between 0 and 50,000 ppm relative to the weight composition (a)+(b)+(d) of at least one transfer agent, and d. optionally qs one or more anionic and / or non-ionic monomers.

6. Use, according to any of the preceding claims, characterized in that the cross-linked cationic polymer is used in an amount between 0.01% and 10% relative to the total amount of bituminous composition, and preferably between 0.01% and 5%, more preferably between 0.01% and 3% relative to the total amount of bituminous composition, all percentages being expressed by weight relative to the total weight of bituminous composition, including the ranges of values ​​"between ... and ...".

7. Composition, characterized in that it comprises at least bitumen and a cross-linked cationic polymer, preferably a cross-linked acrylic polymer.

8. Composition according to claim 7, characterized in that it is a bituminous emulsion.

9. Composition according to claim 7 or claim 8, characterized in that the amount of crosslinked cationic polymer is from 0.01% to 10% by weight based on the total weight of that composition.

10. Composition, according to any one of claims 7 to 9, characterized in that it is a bituminous emulsion comprising: - between 30% and 75% bitumen, - between 0.01% and 10% of at least one cross-linked cationic polymer, - between 0.05% and 5% of at least one surfactant, preferably cationic, and - between 0% and 50% latex, - optionally solvent q.s.p. 100%, it being understood that all percentages are expressed by weight in relation to the total weight of the bituminous composition, and the ranges of values ​​“between ... and ...” are understood as included limits. Petition 870250091903, dated 08 / 10 / 2025, pages 33 / 36