Non-ionic surfactant composition for the preparation of aqueous emulsions

Abstract

The present invention relates to a composition comprising at least one non-ionic surfactant TA1 which is a fatty alcohol alkoxylate and at least one nonionic surfactant TA2 which is a phenol alkoxylate substituted with at least one hydrocarbon chain having from 10 to 60 carbon atoms. The present invention also relates to the use of said composition for preparing aqueous emulsions, in particular bitumen emulsions.

Description

COMPOSITION OF NON-IONIC SURFACTANTS FOR THE PREPARATION OF AQUEOUS EMULSIONS

[0001] The present invention relates to compositions, in particular compositions based on surfactants useful in particular for the preparation of emulsions, more specifically for the preparation of bitumen emulsions, and more specifically still to compositions based on non-ionic surfactants, having good stability properties particularly suitable for the preparation of emulsions in various applications, in particular for the preparation of bitumen emulsions.

[0002] The market for surfactants for bitumen emulsions is constantly growing. These additives are of particular importance for bitumen emulsions, as they play an important role not only in the stability of bitumen emulsions but also in the robustness of bituminous mixes prepared from said emulsions.

[0003] The use of non-ionic surfactants, particularly in formulation, is well known to those skilled in the art and for the preparation of bitumen emulsions, non-ionic emulsifiers are most often used with cationic co-emulsifiers. Non-ionic emulsifiers are also often used, for example to compatibilize the lignin present in certain formulations of bitumen emulsions.

[0004] US Patent No. 3,126,350 describes the production of superstabilized cationic bitumen emulsions using chemically modified lignin. Chemical modifications impose additional operations and constraints, which can be a disadvantage in terms of industrial preparation and the cost of the resulting bituminous emulsions.

[0005] Other types of surfactants have been the subject of extensive studies, and for example in patent US3859227, slow-breaking cationic bituminous formulations comprising at least one alkoxylated alkylphenol are cited. However, such alkoxylated alkylphenols are strictly controlled, as these products are today considered to pose risks to human health. Indeed, the ethoxylated alkylphenols used in bitumen emulsions are certainly recognized as being very good emulsifiers, but it has been shown that these degrade into alkylphenols, now recognized as endocrine disruptors.

[0006] The prior art provides further examples of non-ionic surfactants for use in bituminous emulsions. Thus, patent US3366500 claims a An aggregate coating composition for road asphalt comprising a bitumen, an ethoxylated aromatic alcohol ether as a hydrophilic nonionic surfactant, and an alcohol fatty acid ester as a lipophilic nonionic surfactant. Examples include compositions comprising ethoxylated nonylphenols and fatty acid esters having a long alkyl chain.

[0007] Patent FR2076630 discloses a bituminous binder in the form of an emulsion comprising a non-ionic emulsifier of the long-chain alkyl ethoxylate type, this emulsifier being in particular a long-chain, linear or branched fatty alcohol ethoxylate.

[0008] Application CN105013391 describes a method for preparing an ethoxylated cardanol having 2 to 30 ethyleneoxy (EO) units. This compound is described as a surfactant that can replace ethoxylated nonylphenols for the preparation of bitumen emulsions with high and controlled viscosity. However, this surfactant does not allow for the production of an emulsion that is sufficiently stable over time.

[0009] Application FR2782724 also discloses bitumen emulsions of controlled viscosity, this time comprising two emulsifiers, the first promoting oil-in-water emulsion and the second promoting water-in-oil emulsion. This specific combination of surfactants leads to fast-breaking emulsions.

[0010] It is clear from the prior art that ethoxylated alkylphenols are known as emulsifiers or dispersants in many different fields, such as emulsion polymerization, bitumen emulsions, paints and coatings in general, to name only their main uses. They make it possible to obtain emulsions or dispersions that are distinguished by their high stability. However, and as already indicated above, certain ethoxylated alkylphenols must no longer be used today because of their degradation products recognized as endocrine disruptors, or are simply no longer used because their emulsion stabilizing properties are too weak.

[0011] The objective of the present invention is therefore to find new emulsifiers or combinations of non-ionic emulsifiers making it possible to obtain stable emulsions and having significant versatility to substitute ethoxylated alkylphenols, in particular those linked to their degradation products currently considered toxic, in all of its applications and more particularly for the preparation of bituminous compositions, and even more particularly for the preparation of bitumen emulsions. Still other objectives will become apparent during the description of the invention which follows.

[0012] The inventors have now discovered that the above-mentioned objectives can be solved in whole or at least in part thanks to the composition according to the present invention. Indeed, the inventors have discovered a new combination of emulsifiers making it possible to obtain stable emulsions in numerous applications and more particularly for the preparation of bituminous compositions, and more particularly still for the preparation of bitumen emulsions.

[0013] Thus, and according to a first aspect, the present invention relates to a composition comprising: a) at least one non-ionic surfactant TAi which is a fatty alcohol alkoxylate, and b) at least one non-ionic surfactant TA2 which is a phenol alkoxylate substituted by at least one hydrocarbon chain comprising from 10 to 60 carbon atoms.

[0014] Nonionic surfactant TA1 is an alkoxylated fatty alcohol. Fatty alcohol means an alcohol of formula R 1-OH primary, secondary or tertiary, where R 1 is chosen from a linear or branched hydrocarbon radical containing from 4 to 30 carbon atoms, preferably from 5 to 30 carbon atoms, more preferably from 6 to 30 carbon atoms, more generally from 6 to 20 carbon atoms, advantageously from 6 to 18 carbon atoms. The hydrocarbon radical R 1 may contain one or more unsaturations in the form of a double bond and / or a triple bond and / or a saturated or partially or fully unsaturated ring. The fatty alcohol of formula R 1 -OH is a non-phenolic alcohol, i.e. the -OH group is not attached to a 6-carbon aromatic ring. For the purposes of the invention, the hydrocarbon chains R are preferred 1 saturated or comprising at least one double or triple bond, more preferably the hydrocarbon chain R 1 is a straight or branched alkyl chain.

[0015] Furthermore, it should be understood that the expression "fatty alcohol" also includes mixtures of two or more alcohols of formula R 1 -OH, primary(s), secondary(s) or tertiary(ies), and particularly when the fatty alcohols are derived from renewable raw materials, for example from natural products.

[0016] According to a preferred embodiment of the invention, the alcohol of formula R 1 -OH is a primary alcohol selected from n-butanol, n-pentanol, n-hexanol, 2,2-dimethylbutanol, 2,3-dimethylbutanol, 3,3-dimethylbutanol, n-heptanol, n-octanol, 2-ethylhexanol, n-nonanol, n-decanol, isodecanol, n-undecanol, n-dodecanol, isotridecanol. This list is not exhaustive, however, and other primary alcohols could also be cited.

[0017] According to another embodiment of the invention, the alcohol of formula R 1-OH is a secondary alcohol selected from 2-butanol, 2-pentanol, 2-hexanol, 3,3-dimethyl-2-butanol, 2-heptanol, 3-heptanol, 4-methyl-2-pentanol, 2-octanol, 3-octanol, 4-octanol, 2-nonanol, 3-nonanol, 4-nonanol, 2-decanol, 3-decanol, 2-undecanol, 3-undecanol, 2-dodecanol, 3-dodecanol. This list is not exhaustive and other secondary alcohols could also be mentioned.

[0018] Among the alcohols of formula R 1 -OH, alcohols chosen from 2-octanol, 2-ethylhexanol, isodecanol, isotridecanol, 4-methyl-2-pentanol are particularly preferred.

[0019] To form the nonionic surfactant TAi, the fatty alcohol of formula R 1 -OH described above is alkoxylated, according to any method well known to those skilled in the art. Indeed, it has been demonstrated that the alkoxylated units present in the fatty alcohol of formula R1 -OH participate in the formation of the desired emulsion. According to a preferred embodiment of the invention, the number of alkoxylated units of the non-ionic surfactant TAi is between 6 and 100, more preferably between 7 and 50, more preferably between 8 and 50, better still between 8 and 30.

[0020] The alkoxylated unit generally comprises from 1 to 4 carbon atoms, more generally from 2 to 4 carbon atoms, and may optionally comprise one or more hydroxyl functions, more specifically optionally one hydroxyl function.

[0021] According to one embodiment of the invention, the alkoxylated unit is chosen from ethylene-oxy, propylene-oxy, butylene-oxy and glycidyl-oxy units. By "ethylene-oxy" is meant the unit -CH2-CH2-O, by "propylene-oxy" is meant the unit -O-CH2-CH(CH3)- or the unit -CH2-CH(CH3)-O-, by "butylene-oxy" is meant the unit -O-CH2-C(C2H5)H-, or the unit -CH2-C(C2H5)HO, and by "glycidyl-oxy" is meant the unit -O-CH(CH2OH)-CH2-, the unit -CH(CH2OH)-CH2-O-, the unit -O-CH2-CH(OH)-CH2-, or the unit -CH2-CH(OH)-CH2-O-. It is understood that the alkoxylated units of the non-ionic surfactant TA1 may be the same or different, and when different may be distributed randomly, alternately, by or in blocks or any combination of these distributions. As a general rule, and customarily, the alkoxylated chain of the non-ionic surfactant TA1 is terminated by a hydroxyl group (-OH).

[0022] For the purposes of the invention, and according to a preferred embodiment, the non-ionic surfactant TA1 comprises identical alkoxylated units, and more preferably the non-ionic surfactant TA1 comprises ethoxylated units. Examples of non-ionic surfactants TA1 are those marketed under the names Neoliens®, Sensio®, Ensoline® by Arkema, Berol® by Nouryon, Lutensol®, Pluronic® or Plurafac® by BASF, Emulsogen® or Genapol® by Clariant, Marlipal® or Lialet® by Sasol, Greenbentin® or Imbentin® by Kolb.

[0023] Among the preferred non-ionic surfactants TAi, mention may be made, by way of non-limiting examples, of 2-octanol carrying 15 ethoxyl units (also noted as 2-octanol 15OE), 2-octanol carrying 8 to 30 ethoxyl units, 2-ethylhexanol carrying 8 to 30 ethoxyl units, 4-methyl-2-pentanol carrying 8 to 30 ethoxyl units, isodecanol carrying 8 to 30 ethoxyl units, isotridecanol carrying 8 to 30 ethoxyl units.

[0024] As indicated previously, the composition according to the invention comprises, in addition to said at least one non-ionic surfactant TAi explained above, at least one non-ionic surfactant TA2 which is a phenol alkoxylate substituted by at least one hydrocarbon chain R 2 containing 10 to 60 carbon atoms.

[0025] The hydrocarbon chain R 2 , a substituent of the phenolic group of the non-ionic surfactant TA2, is linear or branched and generally comprises from 10 to 60 carbon atoms, preferably from 12 to 50 carbon atoms, more preferably from 12 to 30 carbon atoms. The hydrocarbon chain R 2 may contain one or more unsaturations in the form of a double bond and / or a triple bond and / or a saturated or partially or totally unsaturated ring. For the purposes of the invention, the hydrocarbon chains R are preferred 2saturated or comprising at least one double or triple bond, more preferably the hydrocarbon chain R 2 is a linear or branched hydrocarbon chain, saturated or containing one to three double bonds.

[0026] The phenolic group of the non-ionic surfactant may also comprise one or more other substituents, such as, for example and without limitation, one or more substituents chosen from an alkyl radical comprising from 1 to 4 carbon atoms in a straight or branched chain, and a hydroxyl group (-OH).

[0027] According to a preferred embodiment of the invention, the phenol substituted by at least one hydrocarbon chain R 2is chosen from phenolic compounds substituted by a hydrocarbon chain with 15 carbon atoms, and optionally comprising one, two or three double bond(s), phenolic compounds substituted both by a second hydroxyl function and by a hydrocarbon chain with 15 carbon atoms, and optionally comprising one, two or three double bond(s), phenolic compounds substituted both by a second hydroxyl function, by a methyl group (-CH3) and by a hydrocarbon chain with 15 carbon atoms, and optionally comprising one, two or three double bond(s). Among the compounds listed above, the compounds known under the names cardanol, cardol and methylcardol are particularly preferred, which are mixtures of phenols substituted by linear hydrocarbon chains with 15 saturated and unsaturated carbon atoms (1, 2 and 3 double bonds).

[0028] To form the non-ionic surfactant TA2, the phenol substituted by at least one hydrocarbon chain R 2 described above is alkoxylated, according to any method well known to those skilled in the art. The number of alkoxylated units of the non-ionic surfactant TA2 is between 2 and 100, preferably between 4 and 100, more preferably between 10 and 100, more preferably between 10 and 80, for example between 15 and 70.

[0029] The alkoxylated unit of the non-ionic surfactant TA2 generally comprises from 1 to 4 carbon atoms, more generally from 2 to 4 carbon atoms, and may optionally comprise one or more hydroxyl functions, more specifically optionally one hydroxyl function.

[0030] According to one embodiment of the invention, the alkoxylated unit of the non-ionic surfactant TA2 is chosen from the ethylene-oxy, propylene-oxy, butylene-oxy and glycidyl-oxy units, where ethylene-oxy, propylene-oxy, butylene-oxy and glycidyl-oxy are as defined above. It is understood that the alkoxylated units of the non-ionic surfactant TA2 may be identical or different, and when they are different may be distributed randomly, alternately, by or in blocks or any combination of these distributions.

[0031] For the purposes of the invention, and according to a preferred embodiment, the non-ionic surfactant TA2 comprises identical alkoxylated units, and more preferably the non-ionic surfactant TA2 comprises ethoxylated units. As for the non-ionic surfactant TA1, as a general rule, and in a customary manner, the alkoxylated chain of the non-ionic surfactant TA2 is terminated by a hydroxyl group (-OH).

[0032] Among the preferred non-ionic surfactants TA2, mention may be made, as non-limiting examples, of cardanols carrying 15 to 60 ethoxyl units, for example cardanol carrying 30 ethoxyl units (also noted as cardanol 30OE).

[0033] The composition of the present invention can be easily prepared by simply mixing at least one non-ionic surfactant TA1 and at least one non-ionic surfactant TA2, according to any conventional mixing method well known to those skilled in the art. Alternatively, the composition of the invention can be directly prepared by mixing said at least one non-ionic surfactant TA1 and said at least one non-ionic surfactant TA2, at the time of use.

[0034] In the composition according to the present invention, the proportions of non-ionic surfactant(s) TA1 and non-ionic surfactant(s) TA2 can vary within large proportions, depending on the desired effect and the use for which the composition is intended. Generally, the weight proportion TAI / TA2 is between 1 / 99 and 99 / 1, preferably between 5 / 95 and 95 / 5, more preferably between 10 / 90 and 90 / 10, better still between 15 / 85 and 85 / 15, and most often between 20 / 80 and 80 / 20, for example 25 / 75 and 75 / 25, or 40 / 60 and 60 / 40.

[0035] Examples of compositions according to the invention which are particularly preferred include, without limitation, mixtures of mixtures of alkoxylated 2-octanol and alkoxylated cardanol, alkoxylated 2-ethylhexanol and alkoxylated cardanol, alkoxylated 4-methyl-2-pentanol and alkoxylated cardanol, alkoxylated isodecanol and alkoxylated cardanol, alkoxylated isotridecanol and alkoxylated cardanol. More specifically, non-limiting examples that may be mentioned are mixtures of ethoxylated 2-octanol and ethoxylated cardanol, and more particularly mixtures of 2-octanol 15OE and cardanol 30OE, mixtures of 2-octanol 20OE and cardanol 30OE, mixtures of 2-octanol 15OE and cardanol 60OE, mixtures of 2-octanol 20OE and cardanol 60OE, and more particularly: - mixtures 2-octanol 15OE / cardanol 30OE, in weight proportion 3 / 1, - mixtures 2-octanol 15OE / cardanol 30OE, in weight proportion 1 / 1, - 2-octanol 15OE / cardanol 30OE mixtures, in weight proportion 1 / 3 - mixtures 2-octanol 15OE / cardanol 60OE, in weight proportion 3 / 1, - mixtures 2-octanol 15OE / cardanol 60OE, in weight proportion 1 / 1, - mixtures 2-octanol 15OE / cardanol 60OE, in weight proportion 1 / 3, - 2-octanol 20OE / cardanol 30OE mixtures, in a weight ratio of 3 / 1, - 2-octanol 20OE / cardanol 30OE mixtures, in weight proportion 1 / 1, - 2-octanol 20OE / cardanol 30OE mixtures, in weight proportion 1 / 3, - 2-octanol 20OE / cardanol 60OE mixtures, in a weight ratio of 3 / 1, - 2-octanol 20OE / cardanol 60OE mixtures, in a weight ratio of 1 / 1, and - 2-octanol 20OE / cardanol 60OE mixtures, in weight proportion 1 / 3.

[0036] The composition according to the present invention may further comprise one or more other surfactants, chosen from anionic, cationic, amphoteric surfactants and zwitterions, such as, and by way of non-limiting examples, surfactants chosen from amine surfactants, phosphate surfactants, surfactants with quaternary amine function, surfactants with sulfate function, surfactants with sulfonate function, surfactants with carboxylate function, betaines, and others.

[0037] Likewise, the composition according to the invention may comprise, if desired or if necessary, one or more additives and fillers well known to those skilled in the art and most often chosen from rheology modifiers, viscosity modifiers, pH modifiers, colorants, pigments, flavorings, preservatives, natural or synthetic polymers and others to name only those most commonly used.

[0038] The composition according to the invention can advantageously be used to form emulsions, and in particular bituminous emulsions. For this purpose, the composition according to the invention can be supplemented with water and acid in order to form a soap. The quantity of water that may be present in the soap can vary within very large proportions and can generally be between 0 and 99.99% by weight of water relative to the total weight of the soap, limits excluded, preferably between 1% and 99% by weight of water relative to the total weight of the soap, limits included.

[0039] According to a preferred embodiment, the soap as defined above is in the form of an “acid” soap. By “acid”, for the purposes of the present invention, is meant that the pH of the soap is less than 7, preferably less than 6, more preferably, it is between 0 and 7, preferably between 1 and 6, preferably between 1 and 4, for example 2. The pH value can be adjusted by adding a strong or weak acid, organic or mineral.

[0040] Preferably, the pH value is adjusted for example by adding at least one acid chosen, for example and by way of non-limiting example, from phosphoric acids, hydrochloric acid, acetic acid, methanesulfonic acid, and mixtures of two or more of them in all proportions. The composition according to the present invention, and the soaps prepared from said composition, are generally in liquid form at room temperature, of homogeneous appearance, and without precipitate.

[0041] As indicated above, the composition according to the present invention, as well as the soaps prepared from said composition, may optionally comprise one or more additives commonly used in the field, among which may be mentioned, without limitation, rheological agents, colorants, stabilizers, surfactants, as well as any other additive well known to those skilled in the art. According to a preferred aspect, the additives which may be present do not comprise a (hetero)aromatic nucleus, in a very preferred manner, the composition of the invention, and the soaps which contain it, do not contain alkoxylated nonylphenol.

[0042] It has been observed quite surprisingly that, unlike the non-ionic surfactants TA1 and TA2 taken separately, the composition of the present invention, which comprises at least one non-ionic surfactant TA1 and at least one non-ionic surfactant TA2, makes it possible to obtain stable emulsions having good properties, in particular when used for the manufacture of emulsions, in terms of viscosity and particle size, among others. The composition of the present invention therefore makes it possible to envisage its use in all the fields of application where ethoxylated nonylphenols are generally used, which can degrade into nonylphenols, currently listed as endocrine disruptors.

[0043] Examples of application of the composition according to the present invention include, but are not limited to, the field of coatings, paints, fertilizers, bitumen, petroleum, detergents, cosmetics, emulsion polymerization, treatment of plant crops, biofuels, to name only the main ones, and more particularly all possible uses where it is necessary to have stable emulsions. It should be noted that the non-ionic surfactants TAi and TA2 are particularly suitable for use as surfactants for oil-in-water type emulsions.

[0044] Among the possible uses, the composition according to the present invention is of particular interest for the preparation of bitumen emulsions. Thus, and according to a second aspect, the present invention relates to the use of a composition comprising at least one non-ionic surfactant TA1 and at least one non-ionic surfactant TA2, as defined above for the production of bituminous emulsions.

[0045] The invention thus relates to the use of at least two nonionic surfactants TA1 and TA2 as they have just been defined for producing aqueous emulsions, and in particular bitumen emulsions. The emulsions prepared with the nonionic surfactants TA1 and TA2 as they have just been defined, and which do not contain ethoxylated nonylphenols, have, in particular in terms of particle size and stability, and whatever the field of application, properties entirely equivalent to those observed with the said ethoxylated nonylphenols which are no longer desired for the reasons already mentioned above. Thus, the present invention relates to the use of the composition described above as a surfactant for the preparation of a bituminous emulsion.

[0046] It has thus been discovered, and this represents yet another aspect of the present invention, that bitumen emulsions, prepared from the compositions according to the invention as defined above, are stable and have good application properties in coating.

[0047] According to one embodiment of the invention, the composition is used at a low dosage, typically between 0.1% and 5%, preferably between 0.1% and 3%, more preferably between 0.5% and 2.0%, by weight of composition, limits included, relative to the total weight of the bitumen emulsion.

[0048] The bitumen emulsions thus produced comprise from 30% to 75% by weight of bitumen and preferably from 40% to 75% by weight of bitumen, relative to the total weight of the emulsion, the remainder to 100% by weight being provided by water.

[0049] More specifically, the invention relates to a bitumen emulsion comprising: - from 30% to 75% by weight of bitumen and preferably from 40% to 75% by weight of bitumen, relative to the total weight of the emulsion, - from 0.1% to 5%, preferably from 0.1% to 3%, more preferably from 0.5% to 2.0%, by weight of the composition defined above, limits included, relative to the total weight of the bitumen emulsion, and - water, qsp 100% by weight.

[0050] As already indicated above, the emulsion according to the present invention may optionally further comprise one or more other additives aimed at modifying its viscosity, adjusting its pH or the adhesiveness of the bitumen emulsion.

[0051] It has been observed, quite surprisingly, that emulsions comprising the surfactant composition TAi and TA2 as defined above have quite remarkable properties, particularly in terms of stability over time. These emulsions are also free of compounds likely to generate degradation products currently recognized as endocrine disruptors.

[0052] Another advantage of the emulsions of the invention comprising the surfactant composition TA1 and TA2 lies in the fact that it is non-ionic, which allows the production of non-ionic, cationic or anionic emulsions. Finally, a particularly suitable use of the surfactant composition TA1 and TA2 is the preparation of so-called slow-breaking bitumen emulsions.

[0053] The present invention also relates to a process for preparing a bitumen emulsion using at least one composition as described above, said process comprising at least one step of mixing, preferably under high shear, at least one bitumen, at least one composition as defined above and water. The order of addition (bitumen, composition, water) will be adapted according to the nature of the bitumen, the composition, as well as the knowledge of a person skilled in the art. The process also comprises a possible step of acidifying the medium in order to obtain a pH value as indicated above.

[0054] The process is generally carried out at a temperature sufficient to ensure good homogenization, depending on the type of bitumen used. As a general rule, the emulsion is prepared at a temperature between room temperature and 160°C, preferably between 40°C and 160°C and more preferably between 60°C and 150°C, more generally between 60°C and 140°C, for example between 70°C and 140°C. The temperature for preparing the bituminous emulsion can typically be adapted depending on the penetrability of the bitumen used, as is well known to those skilled in the art.

[0055] According to a preferred aspect of the process for preparing the emulsion according to the present invention, a soap is prepared, at room temperature, or under slight heating (for example from 30°C to 80°C, preferably from 40°C to 70°C, more preferably from 40°C to 50°C), by dispersing at least one composition as defined above in water, then this soap is acidified (generally to a pH between 1.5 and 5 and preferably between 2 and 3.5) by adding at least one acid. The "acid" soap obtained is then mixed under high shear with at least one bitumen at the temperatures indicated above.

[0056] High shear mixing can be carried out using any equipment known to those skilled in the art. By way of non-limiting example, mention may be made of colloidal mill type devices, of which the Atomix® brand is a representative.

[0057] Thus, and according to a preferred embodiment, the present invention relates to a process for preparing a bitumen emulsion as defined above, said process comprising: - at least one mixing step, preferably under high shear, of at least one bitumen, of at least one composition as described above and of water, - a possible step of acidification of the medium in order to obtain a pH value of less than 7, preferably less than 6, more preferably between 0 and 7, preferably between 1 and 6, preferably between 1 and 4, for example 2, said process being carried out at a temperature of between room temperature and 160°C, preferably between 40°C and 160°C and more preferably between 60°C and 150°C, more generally between 60°C and 140°C, for example between 70°C and 140°C.

[0058] The bitumen emulsion may optionally comprise one or more additives commonly used in the field, among which may be mentioned, without limitation, viscosifiers, natural or synthetic latexes, thickeners, fluxes, plasticizers, as well as any other additive making it possible to adjust the properties of the emulsion, such as for example the process additives cited in documents EP1057873, EP2035504, EP 2766320 and EP3978456.

[0059] The bitumens used in the invention are of any type known to those skilled in the art, from different origins, and for example those of natural origin, those contained in deposits of natural bitumen, natural asphalt or oil sands. In the context of the present invention, the bitumens can also be bitumens originating from the refining of crude oil (atmospheric and / or vacuum distillation of oil), these bitumens possibly being blown, visco-reduced and / or deasphalted.

[0060] Bitumens can be hard grade or soft grade bitumens. The different bitumens obtained by refining processes can be combined with each other. to obtain the best technical compromise. The bitumens used can also be bitumens fluxed by the addition of volatile solvents, petroleum-based fluxes, carbochemical fluxes and / or plant-based fluxes.

[0061] Polymer-modified bitumens can also be used. Examples of polymers that may be mentioned include, but are not limited to, thermoplastic elastomers such as random or block copolymers of styrene and butadiene, linear or star-shaped (SBR, SBS) or of styrene and isoprene (SIS), optionally crosslinked, copolymers of ethylene and vinyl acetate, homopolymers and olefinic copolymers of ethylene (or propylene, or butylene), polyisobutylenes, polybutadienes, polyisoprenes, poly(vinyl chloride), rubber crumb or any polymer used for modifying bitumens and their mixtures. A quantity of polymer of 2% to 10% by weight relative to the weight of bitumen is generally used.

[0062] Synthetic bitumens, also known as clear, pigmentable, or colorable bitumens, can also be used. These bitumens contain little or no asphaltenes and can therefore be colored. These synthetic bitumens are based on petroleum resin and / or indene-coumarone resin and lubricating oil, as described, for example, in patent EP179510.

[0063] Advantageously, the bitumen is a bitumen with a penetrability measured according to standard EN 1426 of between 10 and 300, preferably between 20 and 220, more preferably between 70 and 220.

[0064] The invention also relates to the coatings prepared with the aforementioned bitumen emulsions and aggregates. More particularly, the invention relates to the coatings comprising at least one bitumen emulsion as described previously in the present description and aggregates.

[0065] The aggregates that can be used for the preparation of the coatings according to the present invention can be of any type known to those skilled in the art. Among the aggregates that can be used for the coatings of the present invention, mention may in particular be made, in a non-limiting manner, of aggregates of mineralogical nature, for example of eruptive nature, such as granites, porphyries, basalts, of metamorphic nature, such as schists, gneisses, and of sedimentary nature of siliceous type, such as flints, quartzites, and of carbonate type, such as limestones, dolomites, but also asphalt aggregates (or recycled), clinker, crushed concrete, and others, as well as mixtures of such aggregates.

[0066] The coatings of the present invention can be prepared from at least one bitumen emulsion and aggregates according to any method known to those skilled in the art, and for example by mixing the emulsion with the aggregates.

[0067] The emulsions of the present invention are thus particularly suitable for the preparation of coated materials, for example semi-warm coated materials, that is to say, the temperature of the aggregates during the mixing phase with the bitumen emulsion is between ambient temperature and 100°C, for example also cold coated materials, among which may be mentioned, in a non-limiting manner, gravel emulsions (structuring or reprofiling), cold bituminous concretes, dense, semi-dense or open storable coated materials, and others.

[0068] The emulsions of the present invention are also particularly suitable for producing bonding layers, for soil stabilization and impregnation work, such as for example "prime coat", in-place recycling (or "CIPR" for "Cold-in-Place Recycling" in English), in-place reprocessing with emulsion (or "FDR" for "Full Depth Reclamation" in English), the preparation of coatings, in association or not with one or more other additives and / or fillers, such as for example, clays, powdered limestone, cement, in order to prepare waterproofing coatings and others.

[0069] The use according to the present invention allows in particular the replacement of ethoxylated nonylphenols, in bitumen emulsions, which are recognized as being very good emulsifiers but which degrade into nonylphenols, listed today as being endocrine disruptors.

[0070] The following examples are intended to illustrate the present invention, without however limiting the scope thereof which is defined by the appended claims. Examples

[0071] The following examples make it possible to evaluate the effectiveness of the composition according to the invention. In particular, these examples show that the composition according to the invention provides better results in comparison with the surfactants taken separately and in relation to a reference. As indicated below, the stability of bitumen emulsions can in particular be measured by cement stability tests (NF EN 12848) and by measuring the rupture index (application of NF EN 13075-1 for a cationic, non-ionic or anionic emulsion). Description of test methods

[0072] The tendency to sedimentation after 7 days of storage is assessed according to standard NF EN 12847 (July 2009), “Determination of the tendency to settling of bitumen emulsions”. The emulsions are placed in a 100 mL graduated cylinder. After 7 days of storage at room temperature without stirring, the water content is determined on the upper 10 mL and the lower 10 mL. The emulsion is considered stable if the difference in binder content between the two fractions is less than 5%.

[0073] The rupture index is measured according to the NF EN 13075-1 standard of December 2016, “Bitumens and bituminous binders - Determination of rupture behavior - Part 1: Determination of the rupture index of cationic bitumen emulsions, mineral fines method” with a Sikaisol filler. The test consists of gradually adding filler to a bitumen emulsion while stirring it simultaneously. The rupture is assessed visually from the moment the emulsion solidifies.

[0074] Homogeneity by sieving is assessed according to standard NF EN 1429 (August 2013) “Bitumens and bituminous binders - Determination of the residue on sieve of bitumen emulsions and determination of storage stability by sieving”. The emulsion is passed through a 500 pm mesh sieve. The sieve oversize is the emulsion residue remaining on the sieve at the end of this operation. Example 1: Preparation of bitumen emulsions

[0075] Bitumen emulsions are made with two non-ionic surfactants separately or in combination and with ethoxylated nonylphenol. Unless otherwise stated, dosages are expressed in kilograms per tonne (kg / to). The emulsion contents are detailed in Table 1 below: -- Table 1 --

[0076] Emulsion R1 is a reference emulsion containing only a non-ionic surfactant of the alkoxylated cardanol type, cardanol with 30 ethoxyl units. Emulsion R2 is a reference emulsion containing only a non-ionic surfactant of the ethoxylated branched fatty alcohol type, 2-octanol with 15 ethoxyl units. Emulsion R3 is a reference emulsion containing ethoxylated nonylphenol. Emulsions E1, E2 and E3 are emulsions according to the invention containing mixtures of 2-octanol 15OE and cardanol 30OE in various proportions.

[0077] The emulsions were prepared according to an identical protocol using a progressive enrichment laboratory mill (marketed by Herbert Rink Elektromaschinenbau GmbH). The properties of the emulsions obtained are presented in Table 2 below: - Table 2 -- not feasible, beginning of rupture

[0078] This example shows a very strong improvement in emulsion stability (higher IREC and improved storage stability) using a composition comprising two non-ionic surfactants according to the invention, compared to emulsions prepared with each of the non-ionic surfactants separately.

[0079] It is further observed that the properties of the emulsions according to the invention are very similar to those of the emulsion produced with an ethoxylated nonylphenol, thus demonstrating that the composition according to the invention can completely replace ethoxylated nonylphenol for the preparation of emulsions. Example 2: Compatibility with cationic surfactants

[0080] Spreading type cationic bitumen emulsions are produced. Unless otherwise stated, dosages are expressed in kilograms per tonne (kg / to). The emulsion contents are detailed in Table 3 below: -- Table 3 -- * Stabiram® MS6 (Arkema)

[0081] Emulsion R4 is a reference emulsion containing ethoxylated nonylphenol and a quaternary ammonium cationic co-surfactant. Emulsion E4 is an emulsion according to the invention comprising a non-ionic surfactant TAi, a non-ionic surfactant TA2, and the same quaternary ammonium cationic co-surfactant.

[0082] The emulsions are prepared according to an identical protocol with an automatic Emulbitume laboratory mill including an Atomix® brand mixer. The properties of the emulsions obtained are presented in Table 4 below: - Table 4 --

[0083] This example shows that the composition according to the invention, in association with a cationic surfactant, makes it possible to obtain an emulsion with similar, or even better, properties, particularly in terms of stability, compared to the properties obtained with an emulsion based on ethoxylated nonylphenol and the same cationic surfactant. It is thus also demonstrated here that the composition according to the invention can completely replace ethoxylated nonylphenol for the preparation of emulsions. Example 3: effect of the number of alkoxyl units

[0084] Bitumen emulsions are made with mixtures of non-ionic surfactants, the ethoxylated fatty alcohol present having a number of ethoxylates of 8 (E5 and E6) and 4 (Comparative example). The emulsions are prepared according to a protocol identical to that described in examples 1 and 2 of the patent with a laboratory mill with progressive enrichment (marketed by Herbert Rink Elektromaschinenbau GmbH).

[0085] Unless otherwise stated, dosages are expressed in kilograms per tonne (kg / to). The emulsion contents are detailed in Table 5 below: -- Table 5 --

[0086] The properties of the emulsions are presented in the following Table 6: -- Table 6 --

[0087] The characteristics of the emulsions obtained with E5 and E6, both containing 2-octanol at 8EO, are entirely consistent in terms of homogeneity, breaking index and tendency to sedimentation. On the other hand, for the comparative example, containing 2-octanol at 4EO, the emulsion does not set. This example shows the very strong dependence of the emulsifying capacity of the mixture on the number of alkoxyl units in the fatty alcohol used.

Claims

CLAIMS 1. Composition comprising: a) at least one non-ionic surfactant TAi which is a fatty alcohol alkoxylate, and b) at least one non-ionic surfactant TA2 which is a phenol alkoxylate substituted by at least one hydrocarbon chain comprising from 10 to 60 carbon atoms.

2. Composition according to claim 1, in which the non-ionic surfactant TAi is an alkoxylated fatty alcohol, the fatty alcohol being an alcohol of formula R 1 -OH primary, secondary or tertiary, where R 1 is chosen from a linear or branched hydrocarbon radical comprising from 4 to 30 carbon atoms, preferably from 5 to 30 carbon atoms, more preferably from 6 to 30 carbon atoms, more generally from 6 to 20 carbon atoms, advantageously from 6 to 18 carbon atoms.

3. Composition according to claim 1 or claim 2, in which the non-ionic surfactant TAi is an alkoxylated fatty alcohol, the fatty alcohol being an alcohol selected from n-butanol, n-pentanol, n-hexanol, 2,2-dimethylbutanol, 2,3-dimethylbutanol, 3,3-dimethylbutanol, n-heptanol, n-octanol, 2-ethylhexanol, n-nonanol, n-decanol, isodecanol, n-undecanol, n-dodecanol, isotridecanol, 2-butanol, 2-pentanol, 2-hexanol, 3,3-dimethyl-2-butanol, 2-heptanol, 3-heptanol, 4-methyl-2-pentanol, 2-octanol, 3-octanol, 4-octanol, 2-nonanol, 3-nonanol, 4-nonanol, 2-decanol, 3-decanol, 2-undecanol, 3-undecanol, 2-dodecanol, and 3-dodecanol.

4. Composition according to any one of claims 1 to 3, in which the non-ionic surfactant TAi is an alkoxylated fatty alcohol, the number of alkoxylated units of the non-ionic surfactant TAi being between 6 and 100, preferably between 7 and 50, more preferably between 8 and 50, better still between 8 and 30.

5. Composition according to any one of claims 1 to 4, in which the non-ionic surfactant TAi is chosen from 2-octanol carrying 15 ethoxyl units, 2-octanol carrying 8 to 30 ethoxyl units, 2-ethylhexanol carrying 8 to 30 units ethoxyl, 4-methyl-2-pentanol carrying 8 to 30 ethoxyl units, isodecanol carrying 8 to 30 ethoxyl units, and isotridecanol carrying 8 to 30 ethoxyl units.

6. Composition according to any one of the preceding claims, in which the non-ionic surfactant TA2 is a phenol alkoxylate substituted by at least one hydrocarbon chain R 2linear or branched having from 10 to 60 carbon atoms, preferably from 12 to 50 carbon atoms, more preferably from 12 to 30 carbon atoms.

7. Composition according to any one of the preceding claims, in which the non-ionic surfactant TA2 is a substituted phenol alkoxylate chosen from cardanol, cardol and methylcardol.

8. Composition according to any one of the preceding claims, in which the non-ionic surfactant TA2 is a phenol alkoxylate substituted by at least one hydrocarbon chain comprising from 10 to 60 carbon atoms, and comprising a number of alkoxyl units of between 2 and 100, preferably between 4 and 100, more preferably between 10 and 100, more preferably between 10 and 80, for example between 15 and 70.

9. Composition according to any one of the preceding claims, in which the non-ionic surfactant TA2 is chosen from cardanols carrying 15 to 60 ethoxyl units.

10. Composition according to any one of the preceding claims, in which the weight proportion TAI / TA2 is between 1 / 99 and 99 / 1, preferably between 5 / 95 and 95 / 5, more preferably between 10 / 90 and 90 / 10, better still between 15 / 85 and 85 / 15, and most often between 20 / 80 and 80 / 20, advantageously between 25 / 75 and 75 / 25, or even between 40 / 60 and 60 / 40.

11. Composition according to any one of the preceding claims, comprising the mixtures chosen from: - mixtures 2-octanol 15OE / cardanol 30OE, in weight proportion 3 / 1, - mixtures 2-octanol 15OE / cardanol 30OE, in weight proportion 1 / 1, - 2-octanol 15OE / cardanol 30OE mixtures, in weight proportion 1 / 3 - mixtures 2-octanol 15OE / cardanol 60OE, in weight proportion 3 / 1, - mixtures 2-octanol 15OE / cardanol 60OE, in weight proportion 1 / 1, - mixtures 2-octanol 15OE / cardanol 60OE, in weight proportion 1 / 3, - 2-octanol 20OE / cardanol 30OE mixtures, in a weight ratio of 3 / 1, - 2-octanol 20OE / cardanol 30OE mixtures, in a weight ratio of 1 / 1, - 2-octanol 20OE / cardanol 30OE mixtures, in weight proportion 1 / 3, - mixtures 2-octanol 20OE / cardanol 60OE, in weight proportion 3 / 1, - 2-octanol 20OE / cardanol 60OE mixtures, in a weight ratio of 1 / 1, and - 2-octanol 20OE / cardanol 60OE mixtures, in weight proportion 1 / 3.

12. Composition according to any one of the preceding claims, further comprising one or more other surfactants, chosen from anionic and cationic, amphoteric, and zwitterion surfactants such as, and by way of non-limiting examples, surfactants chosen from amine surfactants, phosphate surfactants, quaternary amine-functional surfactants, sulfate-functional surfactants, sulfonate-functional surfactants, carboxylate-functional surfactants, and betaines.

13. Use of a composition according to any one of claims 1 to 12, for producing aqueous emulsions.

14. Use of the composition according to claim 13 as a surfactant for the preparation of a bituminous emulsion.

15. Bitumen emulsion comprising: - from 30% to 75% by weight of bitumen and preferably from 40% to 75% by weight of bitumen, relative to the total weight of the emulsion, - from 0.1% to 5%, preferably from 0.1% to 3%, more preferably from 0.5% to 2.0%, by weight of composition according to any one of claims 1 to 12, limits inclusive, relative to the total weight of the bitumen emulsion, and - water, qsp 100% by weight.

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