MXPA01002983A - Use of essentially amorphous cellulose nanofibrils as emulsifying and/or stabilising agent - Google Patents

Abstract

The invention concerns the use of essentially amorphous cellulose nanofibrils having a crystallinity index not more than 50%as emulsifying and/or stabilising agent in a dispersion. The nanofibrils can be used in the form of an aqueous suspension, or in dispersible dry form. Said nanofibrils can also be used in combination with at least an additive and optionally at least a co-additive.

Description

USE OF ESSENTIALLY AMORPHAS CELLULOSE NANOFIBRILLES AS AN EMULSIFYING AGENT AND / OR STABILIZER Description of the invention The present invention relates to the use of essentially amorphous cellulose nanofibrils having a crystallinity ratio of less than or equal to 50%, as an emulsifying agent and / or stabilizer of a dispersion. This also refers to the use of the above-mentioned nanofibrils with at least one additive and optionally with at least one co-additive. In the sense of the invention, a dispersion designates a system consisting of at least two non-miscible phases. This may correspond, for example: to a liquid-in-liquid emulsion, the liquids being immiscible with each other, mainly an oil-in-water emulsion, or a water-in-oil emulsion; to a multiple emulsion constituted for example of three liquids where at least 2 are not miscible among them, mainly a water-in-oil emulsion in water or oil in water in oil, the aqueous and oily phases can be identical or different; to a foam constituted of gas dispersed in a liquid or an emulsion; - to an emulsion or suspension of solid in a liquid, such as latexes corresponding to colloidal suspensions of polymer particles in a liquid phase; to a system formed of a gas and two different liquids. The object of the present invention is applied to any dispersion as defined above, and more particularly to the systems listed in a non-limiting manner. At this stage, it is important to define the terms "emulsifier" and "stabilizer". In the context of the present invention, the term "emulsifier" designates a compound which abates the interfacial tension between two immiscible phases (e.g. water / oil) and thus allows a strong increase in the specific surface area of the phase to be emulsified. . In this way, the mechanical energy necessary to form the dispersion is diminished. The emulsion may or may not stabilize the emulsion in a durable manner by providing example charges to the surface of the droplets "electrostatic stabilization". By "stabilizer" is meant any compound that will retard or even inhibit the phenomena of destabilization of the emulsion or of the dispersion, that is to say the acrid or flocculation that leads sooner or later to the coalescence of the droplets or to the coagulation of the solids in a dispersion. The stabilizer can exert its function in different ways: - either by adsorbing the droplets on the surface without necessarily reducing their interfacial tension and stabilizing them sterically, or by structuring and viscosifying the medium in such a way that the speed of accretion of the droplets or flocculation of solids is retarded. It can be said that the stabilizer exerts its function forming a type of mechanical barrier that prevents the droplets from accreting or the solids flocculate. Stabilization and emulsification are therefore two distinct but complementary functions. It should be noted that the operating conditions, such as the nature of the phases, the concentration, the pH, the ionic strength, the temperatures, etc., which favor the action of an emulsifier, do not necessarily favor that of a stabilizer. In this way, numerous compounds are known for their function as an emulsifier or as a stabilizer. More rare are those that optimally perform both functions at the same time, and this at small concentrations and for a large number of different systems. By way of indication, mention may be made of xanthan gum, carrageenans, alginates or carboxyl ethylcelluloses, polysaccharides which are known as stabilizing agents for emulsions, but not as emulsifiers. An opposite example is gum arabic which has an emulsifying and stabilizing power but this at high concentrations. Now, the applicant has unexpectedly and surprisingly found that essentially amorphous cellulose nanofibrils where the crystallinity ratio is less than or equal to 50% possess remarkable emulsifying and / or stabilizing properties. Said nanofibrils according to the invention can be both the emulsifying agent and / or stabilizer at relatively low amounts, quite comparable to those of the usual emulsifiers such as TWEEN 20 (polyoxyethylene sorbitan monolaurate) and much lower than gum arabic. Other advantages and features of the present invention will appear more clearly upon reading the description and the following examples. The subject of the present invention is therefore the use of essentially amorphous cellulose nanofibrils having a crystallinity ratio of less than or equal to 50%, as an emulsifying agent and / or stabilizer of a dispersion. More particularly, the object of the invention is the use of essentially amorphous cellulose nanofibrils having a crystallinity ratio of less than or equal to 50%, as an emulsifying agent and stabilizer of a dispersion. In the present invention, the nanofibrils are put into operation in an amount sufficient to emulsify and / or stabilize. In particular, the nanofibrils may be present in an amount comprised between 0.01 to 5% by weight relative to the total weight of the dispersion.

According to an advantageous embodiment of the invention, the nanofibrils are present in an amount comprised between 0.05 to 1% by weight, preferably between 0.1 and 0.8% by weight, based on the total weight of the dispersion. By essentially amorphous, we mean nanofibrils where the proportion of crystallinity is less than or equal to 50%. According to a particular variant of the present invention, the crystallinity ratio is between 15% and 50%. Preferably, the crystallinity ratio is less than 50%. The cellulose nanofibrils that enter into the composition of the formulation according to the present invention are from cells constituted, preferably, of at least about 80% of primary walls. Such characteristics are found with cellulose based on parenchyma cells. For example, citrus fruits, such as lemons, mainly grapefruit, or even sugar beet, are vegetables that comprise such cells. Preferably, the amount of primary walls is at least 85% by weight. Plus particularly, the cellulose coming from the pulp of the sugar beet is put into operation. According to a preferred variant, the nanofibrils of the invention have at least 80% of cells with primary walls. The nanofibrils are advantageously charged on the surface with carboxylic acids and acidic polysaccharides, alone or as a mixture. By carboxylic acids, simple carboxylic acids are understood, as well as their salts. These acids are preferably chosen from uronic acids, or their salts. More particularly, said uronic acids are galacturonic acid, glucuronic acid, or its salts. As polysaccharide acids, mention may be made of pectins, which are more particularly polygalacturonic acids. These acid polysaccharides can be present in a mixture with hemicelluloses. A very advantageous embodiment of the invention is constituted by nanofibrils whose surface is at least charged with galacturonic acid and / or with polygalacturonic acid. It should be noted that this is not a simple mixture between these nanofibrils and the acids and polysaccharides, but above all a close combination between these two types of compounds. In fact, the process of preparation of nanofibrils is such that the acids and polysaccharides are not completely separated from the fibers but remain even on the surface of the latter, giving them very specific properties. In this way, it has been found that it would not be possible to obtain the same properties if these acids and / or polysaccharides were completely separated from the nanofibrils at the time of their preparation to be added subsequently. The cellulose nanofibrils present, on the other hand, a section comprised between approximately 2 and approximately 10 nm. More particularly, the section of the microfibrils is comprised between approximately 2 and approximately 4 nm. The particular microfibrils that enter into the composition of the food formulations have such characteristics due to the fact that a particular preparation process is put into operation, which will now be described. It should be noted that this procedure forms, among others, the purpose of the application for European patent EP 726 356, to which reference may be made for more details. First of all, said process is more particularly carried out on the pulp of the sugar beet after it has undergone a stage of prior extraction of the sucrose, according to the methods known in the art. The preparation process comprises the following steps: (a) first acid or basic extraction, at the outlet of which a first solid residue is recovered. (b) optionally the second extraction carried out under alkaline conditions of the first solid residue, at the end of which a second solid residue is recovered, (c) washing of the first or second solid residue, (d) optionally bleaching the washed residue , (e) the dilution of the solid residue obtained at the end of step (d), in order to obtain a proportion of dry materials comprised between 2 and 10% by weight, (f) homogenization of the diluted suspension.

In step (a), "pulp" is understood to mean moist, dehydrated pulp, preserved by silage or partially dismembered. The extraction step (a) can be carried out in an acid medium or in an alkaline medium. For an acid extraction, the pulp is suspended in a water solution for a few minutes, in order to homogenize the acidified suspension at a pH comprised between 1 and 3, preferably between 1.5 and 2.5. This operation is started with a concentrated solution of an acid such as hydrochloric acid or sulfuric acid. This step can be advantageous for removing the calcium oxalate crystals that may be present in the pulp, and which, due to the fact of their important abrasive character, can cause difficulties in the homogenization step. For an alkaline extraction, the pulp is added to an alkaline solution of a base, for example sodium hydroxide or potassium hydroxide, of a concentration lower than 9% by weight, more particularly less than 6% by weight. Preferably, the concentration of the base is between 1 and 2% by weight.

A small amount of a water-soluble antioxidant agent, such as sodium sulfite Na2S03, may be added in order to limit the oxidation reactions of cellulose. Step (a) is generally carried out at a temperature between about 60 ° C and 100 ° C, preferably between about 70 ° C and 95 ° C. The duration of step (a) is between approximately 1 hour and approximately 4 hours. At the time of step (a), a partial hydrolysis occurs with the release and solubilization of most of the pectins and hemicelluloses, always preserving the molecular mass of the cellulose. The solid residue is recovered from the suspension from stage (a) by putting into operation known methods. In this way, it is possible to separate the solid waste by centrifugation, by vacuum filtration or under pressure, with the filtering cloths, or press filters for example, or even by evaporation. The first solid residue obtained is subjected to a second extraction step, carried out under alkaline conditions.

A second extraction stage is put into operation when the first has been conducted in acidic conditions. If the first extraction has been carried out in alkaline conditions, the second stage is only optional. According to the process, this second extraction is carried out with a base preferably chosen from sodium hydroxide or potassium hydroxide, whose concentration is less than about 9% by weight, preferably between about 1% and about 6% by weight . The duration of the alkaline extraction step is between approximately 1 and approximately 4 hours. This is preferably equal or approximately 2 hours. At the end of this second extraction, if this takes place, a second residue is recovered. In step (c) the residue from step (a) or (b) is washed with water in order to recover the cellulose material residue. The cellulose material of step (c) is then optionally bleached, in step (d), according to the classical methods. For example, a treatment with sodium chlorite, sodium hypochlorite, with hydrogen peroxide can be carried out at a rate of 5-20% in relation to the amount of dry materials treated. Different concentrations of the bleaching agent can be used, at temperatures between about 18 ° C and 80 ° C, preferably between about 50 ° C and 70 ° C. The duration of this step (d) is between about 1 hour and about 4 hours, preferably between about 1 and about 2 hours. A cellulosic material containing between 85 and 95% by weight of cellulose is then obtained. Upon completion of this bleaching step, it may be preferable to wash the cellulose liberally with water. The resulting suspension, optionally bleached, is then rediluted in water at a rate of 2 to 10% dry materials, and then undergoes a homogenization stage. This corresponds to a mixing, crushing or any high mechanical shearing operation, followed by one or several passes of the cell suspension through a small diameter hole, subjecting the suspension to a pressure drop of at least 20 MPa and a shearing action to high speed, followed by a deceleration impact at high speed. Mixing or grinding is effected for example by passing in a mixer or grinder for a duration ranging from a few minutes to approximately one hour, in an apparatus of the type such as WARNING BLENDOR equipped with a four-bladed propeller or grinder or any other another type of shredder, such as a shredder or colloid mill. The homogenization itself will be advantageously carried out in a homogenizer of the MANTON GAULIN type in which the suspension is subjected to a shearing action at high speed and pressure in a narrow passage, and against a shock ring. The MICRO FLUIDIZER, which is a homogenizer mainly composed of a compressed air motor that creates strong pressures, of an interaction chamber in which the homogenization operation (shearing by elongation, shocks and cavitations) and of a chamber at low pressure that allows the depressurization of the dispersion. The suspension is introduced into the homogenizer preferably after the preheating at a temperature comprised between 40 and 120 ° C, preferably comprised between 85 and 95 ° C. The homogenization operating temperature is maintained between 95 and 120 ° C, preferably above 100 ° C. The suspension is subjected to the homogenizer at pressures between 20 and 100 MPa, and preferably greater than 50 MPa. The homogenization of the cellulose suspension is obtained by a number of passes that can vary between 1 and 20, preferably between 2 and 5, just until obtaining a stable suspension. The homogenization operation can advantageously be followed by a high mechanical shearing operation, for example in an apparatus such as ULTRA TURRAX from SYLVERSON. It should be noted that this procedure has been described in the European patent application EP 726 356 filed on 07/02/96, to which reference may be made if necessary. Example 20 of this text mainly gives a suspension preparation mode of essentially amorphous cellulose nanofibrils. In the context of the present invention, nanofibrils can be used in the form of aqueous suspension, as obtained by the procedure described above. According to a particular embodiment of the invention, cellulose nanofibrils can be associated with. less to a polyhydroxylated organic compound (polyOH). More particularly, the polyhydroxy compound (polyOH) is chosen from carbohydrates and their derivatives, and polyols. Concerning carbohydrates, mention may be made more particularly of linear or cyclic monosaccharides having 3 to 6 carbon atoms, and preferably 5 to 6 carbon atoms, oligosaccharides, polysaccharides and their fatty derivatives, such as sucroesters or sucrose esters of fatty acids, alcohol carbohydrates and their mixtures. By way of non-limiting examples of the monosaccharides, fructose, mannose, galactose, glucose, talose, gulose, allose, altrose, idose, arabinose, xylose, lyxose and ribose are suitable. As oligosaccharides, sucrose, maltose and lactose may be mentioned among others.

The polysaccharides can be of animal, vegetable or even bacterial origin. In addition, these can be used in an anionic or non-ionic form. Xanthan gum, succinoglycans, carrageenans, alginates are representative elements of anionic polysaccharides. As regards non-ionic polysaccharides, mention may be made, in particular, of galactomannans, such as guar gum, locust bean gum, starch and its non-ionic derivatives, nonionic derivatives of cellulose. As for the carbohydrate derivatives, sucrose esters of fatty acids, esters of fatty acids, carbohydrates of alcohols of the sorbitol, mannitol type can be mentioned without intending to limit them; carbohydrates or carbohydrates of acids such as gluconic acid, uronic acids, such as galacturonic acid, glucuronic acid, as well as their salts, and carbohydrates of esters such as ethylated carboxy cellulose. As far as polyols are concerned, they can be put into operation in food formulations, glycerol, pentaerythritol, propylene glycol, ethylene glycol and / or polyvinyl alcohols. It should be emphasized that the compounds described above can be used alone or as a mixture. While this particular mode of embodiment is put into operation, the polyhydroxylated organic compound (s) (or polyOH (s)) is or is associated with cellulose nanofibrils in a weight ratio of (polyOH) (s) x 100 / [(polyOH) ) (s) + (NFC)] comprised between 5 and 50%, and preferably between 5 and 30%, In an entirely advantageous manner, this ratio is comprised between 10 and 30%, and preferably between 15 and 30% in According to a particularly advantageous first variant, the hydroxy compound is at least carboxymethylated cellulose Cellulose is a polymer composed of glucose monomer units The carboxylated group is introduced in a manner known per se, by reacting the chloroacetic acid with the cellulose The degree of substitution corresponds to the number of carboxymethylated groups per glucose unit The theoretical maximum degree is 3.

Whether the degree of substitution is greater than 0.95, or less than or equal to this value, it is required that the carboxymethylated cellulose have, respectively, a high or a low degree of substitution. Preferably, carboxymethylcellulose has a degree of substitution greater than 0.95. According to a second variant, the polyhydroxy compound is a combination of carboxymethylated cellulose with at least one of the compounds chosen from monosaccharides, oligosaccharides, nonionic and anionic polysaccharides and their derivatives, carbohydrate derivatives (carbohydrates) such as hydrates of carbon of alcohols, acids and ethers. In particular, the carboxymethylated cellulose is put into operation in combination with at least one of the following compounds: xanthan gum, sorbitol, or sucrose. Optionally, the cellulose nanofibrils may be associated, in addition to the aforementioned polyhydroxy compound, with at least one co-additive chosen from: p the carboxylated cellulose having a degree of substitution less than or equal to 0.95, preferably carboxymethylated cellulose, p the monomers or osidic oligomers, p the compounds of the formula (R1R2N) COA, the formula in which R1 or R2 identical or different, represent hydrogen or an alkyl radical of 1 to 10 carbon atoms, preferably 1 to 5 carbon atoms, A represents hydrogen, an alkyl radical of 1 to 10 carbon atoms, preferably 1 to 5 carbon atoms, or even the group RflRf2N with R'1, R'2, identical or different, representing hydrogen or an alkyl radical with 1 to 10 carbon atoms, preferably 1 to 5 carbon atoms, p cationic or amphoteric surfactants. As regards compounds of the type (R1R2N) COA, it is preferred to use the compounds comprising two amide functional groups. Preferably, urea is used as the co-additive. The cellulose nanofibrils that fall within the scope of the present invention are obtained by drying a dispersion of nanofibrils, preferably in the presence of an additive and optionally a coadditive.

In this way, the cellulose nanofibrils of the present invention can be used in dispersible dry form. Yet another objective of the present invention is the use of the nanofibrils according to the invention, depending on the case in association with an additive, and optionally a co-additive as an emulsifying and / or stabilizing agent in the cosmetic, food, of concrete constructions, drilling fluids, in radical polymerization such as direct or inverse emulsion polymerization, in microemulsion, in suspension, in dispersion, etc. The subject of the invention is also the compositions in the fields of cosmetics, foodstuffs, concrete constructions, drilling fluids, or compositions based on polymer derived from a radical polymerization, comprising the nanofibrils according to the invention. , as the case may be in association with an additive, and optionally a co-additive, as an emulsifying and / or stabilizing agent. Concrete but not limiting examples of the invention are now to be presented.

EXAMPLES Example 1 The purpose of this example is the preparation of cellulose nanofibrils (NFC) in the form of a stock suspension, and in the dry or anhydrous form comprising carboxymethylcellulose (CMC). 1 . Preparation of the mother-dispersion of nanofibrils: The mother-dispersion of nano cellulose fibers is obtained according to the procedure described in example 20 of the patent application EP 726 256; it comprises 2.3% of cellulose nanofibrils and is pre-homogenized in the Ultra-Turrax apparatus at 14,000 revolutions per minute, for one minute for 100 g of dispersion. 2. Preparation of dried nanofibrils comprising carboxymethylcellulose (CMC) The cellulose nanofibrils mother dispersion is obtained according to the procedure described in example 20 of the patent application European EP 726 356; it comprises 2.3% of cellulose microfibrils and is pre-homogenized in the Ultra-Turrax apparatus at 14,000 revolutions per minute per 1 minute for 100 g of dispersion. Carboxymethylcellulose put into operation has a degree of substitution equal to 1.2; of medium viscosity (product BLANOSE 12M8P from AQUALON). The CMC is placed in solution in distilled water and then added to the mother dispersion (NFC) and the whole is stirred with a defolling paddle at 1000 rpm for 30 minutes. The amount of carboxymethylcellulose added is 30% based on the weight of the CMC. The mixture is then poured into glasses and then dried in a ventilated oven at 40 ° C, until an extract of 77% is obtained, controlled by dosing water with the help of an infrared thermobalance. The dry mixture is ground in a coffee mill, then sieved on a 500 μm sieve.

Example 2 This example aims to highlight the emulsifying power of cellulose nanofibrils (NFC). 1 . Measurement of surface tension (water / air) The surface tensions are measured with an automatic KREUSS tensiometer (type K 14) and a WILHELMY lamella.

Measurement of the surface tension of cellulose nanofibrils without additive (mother dispersion): The cellulose nanofibrils are predispersed under moderate agitation in distilled water in order to have a mass concentration of 0.28%. This dispersion is stirred for 15 minutes at 1000 rpm, then homogenized at atmospheric pressure in the Ultra Turrax for 2 minutes at 13500 rpm. A control of the amount of water and the purity of the material allows to verify the theoretical value of the surface tension of the distilled water at 71.1 nM / m at 23 ° C. 50 ml of dispersion is placed in a crystallizer of the tensiometer and allowed to stand for 30 minutes. The platform is then raised to immerse the foil. The solution is allowed to equilibrate for 30 seconds. The value of the surface tension is then determined (see Table I) Measurement of the surface tension of cellulose nanofibrils comprising 30% CMC The dried cellulose nanofibrils of example 1 are predispersed under moderate agitation in distilled water in order to have a mass concentration of 0.4%. This dispersion is then stirred for 15 minutes at 1000 rpm, then homogenized at atmospheric pressure in the Ultra Turrax for 2 minutes at 13500 rpm. The measurement of the surface tension is performed as described above.

Comparative test: Measurement of the surface tension of carboxymethylcellulose (CMC) The dry powder of CMC (whose references are given in example 1) is predispersed under moderate agitation in distilled water in order to obtain a solution whose mass concentration is 0.12%. This dispersion is then stirred for 15 minutes at 1000 rpm, then homogenized at atmospheric pressure in the Ultra Turrax for 2 minutes at 13500 rpm. The measurement of the surface tension is performed as described above (see Table I).

Comparative Test: Measurement of the surface tension of gum arabic The gum arabic is predispersed under moderate agitation in distilled water in order to obtain a solution whose mass concentration is 20%. This dispersion is then stirred for 15 minutes at 1000 rpm, then homogenized at atmospheric pressure in the Ultra Turrax for 2 minutes at 13500 rpm. The measurement of the surface tension is performed as described above (see Table I). 2. Measurement of the interfacial tension (water / oil) Interfacial tensions are measured with a hanging drop tensiometer of the LAUDA TVT11 type. No calibration is necessary with this device, only a preliminary verification of the purity of the water, which must be carried out. The principle of manipulation consists in forming a drop of liquid 1 (water) containing the emulsifier in a continuous medium containing the second liquid 2 (oil) or vice versa (drop formed with the oily phase). At equilibrium, the weight of the drop will be compensated by the interfacial tension of the liquid. An optical detection system measures the volume of the drop whose value can be related to the interfacial tension. The measurements are made in the quasi-static mode, in order to leave the emulsifying agent time to migrate to the interface.

The interfacial tension values are determined after an equilibrium time of 30 minutes. The results reported in Table I show that the NFC significantly reduces superficial and interfacial tensions of oils of very different polarity.

Table I The results in Table I show well that NFCs have an emulsifying power (in terms of interfacial and surface tensions) comparable to gum arabic, but at concentrations much lower than gum arabic.

Example 3 This example aims to highlight the stabilizing power of cellulose nanofibrils (NFC). For this, oil-in-water emulsions (h / e) and droplet size measurements have been prepared by granulometry and optical microscopy.

Preparation of emulsions The dispersions of NFC optionally with additives are made in distilled water at the required concentration as in example 2. The appropriate amount of soybean oil (RISO mark) or n-hexadecane (MERCK) is then added to the aqueous phase (30). % by mass in relation to the aqueous phase) and the whole is pre-homogenized with a homogenizer of the Ultra Turrax IKA T25 type for 1 minute at 9500 rpm. This pre-homogenization is intended to guarantee a uniform passage in the Microfluidizer. In fact, 1 pass is made in the microfluidizer M 110T at 500 bars: the emulsions obtained are beautiful, homogeneous and stable over time.

Stable emulsions of silicone oil type 47 V 100 (Rhodorsil) are also prepared.

Characterization of emulsions The granulometry is determined by laser granulometry (HORIBA device reference LA 910) and by optical microscopy (OLYMPUS device reference BH-2). Measurements are made immediately after emulsification, then at regular intervals after storage. The values of the average diameters shown in Table II show that the use of NFC allows the obtaining of stable emulsions of relatively boxed granulometries. No stable emulsion could be obtained with the CMC since the emulsions coalesce immediately after homogenization.

Table II: Evaluation of emulsions of soybean oil, hexadecane and silicone D corresponds to the average diameter in μm. * I corresponds to the polydispersity index: the closer I is to 1 the more monodispersed are the droplets.

Example 4 The purpose of this example is to show that the NFC together with the CMC as an emulsifying and stabilizing agent, can lead to obtaining a water-in-oil multiple emulsion in water (e / h / e), with a relatively narrow granulometry of 50 micrometers and stable over time.

Composition Soya oil 30% Water of the key 48% Vinegar 12% 13% Sugar 6% NaCl 2.5% NFC / CMC 0.5% Operation mode The sugar is added under stirring at 500 rpm and then the NFC / CMC to water. The stirring is carried out at 1000 rpm and it is kept there for 15 minutes. Vinegar and salt are added immediately and stirring is maintained for 3 minutes. The oil is then added and the whole is stirred for 3 minutes. The assembly is first homogenized for 1 minute at 9500 rpm in the Ultra Turrax IKA T25, and then by the passage to the microfluidizer M 110T at 500 bars. Emulsification is obtained e / h / e beautiful, homogeneous and stable over time.

Claims (22)

1. The use of essentially amorphous cellulose nanofibrils, having a crystallinity ratio of less than or equal to 50%, as an emulsifying agent and / or stabilizer of a dispersion.

2. The use according to claim 1, characterized in that the dispersion is a liquid emulsion in liquid.

3. The use according to claim 2, characterized in that the dispersion is an oil-in-water emulsion.

4. The use according to claim 2, characterized in that the dispersion is a water-in-oil emulsion.

5. The use according to claim 1, characterized in that the dispersion is a multiple emulsion consisting of three liquids.

6. The use according to claim 1, characterized in that the dispersion is a foam constituted of gas dispersed in a liquid or an emulsion.

7. The use according to claim 1, characterized in that the dispersion is an emulsion or suspension of solid in liquid.

8. The use according to claim 1, characterized in that the dispersion is formed of a gas and two different liquids.

9. The use according to any of claims 1 to 8, characterized in that the nanofibrils are present in an amount comprised between 0.01% to 5% by weight with respect to the total weight of the dispersion.

10. The use according to any of claims 8 to 9, characterized in that the nanofibrils are present in an amount comprised between 0.05 to 1% by weight, preferably between 0.1 and 0.8% by weight, based on the total weight of the dispersion.

11. The use according to any of claims 1 to 10, characterized in that the nanofibrils have a crystallinity ratio of between 15 and 50%, preferably less than 50%.

12. The use according to any of claims 1 to 11, characterized in that the nanofibrils are from cells consisting of at least 80% of primary walls.

13. The use according to any of claims 1 to 13, characterized in that the cellulose nanofibrils have at least 80% of cells with primary walls.

14. The use according to any of claims 1 to 13, characterized in that the nanofibrils are loaded on the surface with carboxylic acids and acidic polysaccharides, alone or as a mixture.

15. The use according to any of claims 1 to 14, characterized in that the Cellulose nanofibrils are associated with at least one polyhydroxylated organic compound (polyOH).

16. The use according to claim 15, characterized in that the polyhydroxylated organic compound (polyOH) is chosen from carbohydrates or carbohydrates and their derivatives, and polyols.

17. The use according to any of claims 15 or 16, characterized in that the polyhydroxylated organic compound is associated with the cellulose nanofibrils in a weight ratio (polyOH) x 100 / [(polyOH) + (NFC)] comprises between 5 and 50%, preferably between 5 and 30%.

18. The use according to any of claims 1 to 17, characterized in that the cellulose nanofibrils, and according to the case the polyhydroxylated organic compound (polyOH), are associated to at least one coaditr selected from: p the carboxylated cellulose having a degree of substitution less than or equal to 0.95, preferably of carboxymethylated cellulose, p monomers or osidic oligomers, p the compounds of the formula (RXR2N) COA, the formula in which R1 or R2 identical or different, represent hydrogen or an alkyl radical of 1 to 10 carbon atoms, preferably of 1 to 5 carbon atoms, A represents hydrogen , an alkenyl radical of 1 to 10 carbon atoms, preferably of 1 to 5 carbon atoms, or even the group R "1R'2N with R'1, R'2, identical or different, representing hydrogen or an alkyl radical with 1 to 10 carbon atoms, preferably 1 to 5 carbon atoms, D the cationic or amphoteric surfactants. These coadditives are used alone or as a mixture.

19. The use according to any of claims 1 to 18, characterized in that the nanofibrils are used in the form of an aqueous suspension.

20. The use according to any of claims 1 to 18, characterized in that the nanofibrils are used in the dry dispersible form.

21. The use of the nanofibrils according to any of claims 1 to 14, as the case may be in association with an additive according to any of claims 15 to 17 and optionally a co-additive according to claim 18, as the emulsifying agent and / or stabilizer in the domains of cosmetics, food, concrete constructions, drilling fluids, or radical polymerization.

22. Composition in the cosmetics, food, concrete constructions, drilling fluid, or polymer based compositions derived from a radical polymerization, comprising nanofibrils according to any of claims 1 to 14 according to the case in association with an additive according to any of claims 15 to 17, and optionally a coadjutor according to claim 18, as an emulsifying and / or stabilizing agent.