WO2000016889A2

WO2000016889A2 - Use of essentially amorphous cellulose nanofibrils as emulsifying and/or stabilising agent

Info

Publication number: WO2000016889A2
Application number: PCT/FR1999/002159
Authority: WO
Inventors: Sophie Vaslin; José FAYOS; Robert Cantiani
Original assignee: Rhodia Chimie
Priority date: 1998-09-22
Filing date: 1999-09-10
Publication date: 2000-03-30
Also published as: FR2783437B1; EP1144103A2; WO2000016889A3; FR2783437A1; AU5627099A; BR9913907A; CA2345326A1; JP2002526247A; CN1438918A

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 AMORPHOUS CELLULOSE NANOFIBRILLES AS EMULSIFYING AND / OR STABILIZING AGENT

The present invention relates to the use of essentially amorphous cellulose nanofibrils having a crystallinity rate of less than or equal to 50%, as an emulsifying and / or stabilizing agent for a dispersion.

It also relates to the use of the aforementioned nanofibrils with at least one additive and optionally with at least one co-additive.

Within the meaning of the invention, a dispersion designates a system consisting of at least two immiscible phases. It can correspond for example:

- A liquid-in-liquid emulsion, the liquids being immiscible with each other, in particular an oil-in-water emulsion, or a water-in-oil emulsion;

- a multiple emulsion consisting for example of three liquids, at least 2 of which are immiscible with one another, in particular a water in oil in water or oil in water in oil emulsion, the water and oil phases possibly being identical or different;

- a foam consisting of gas dispersed in a liquid or an emulsion;

- an emulsion or suspension of solid in a liquid, such as latexes which correspond to colloidal suspensions of polymer particles in a liquid phase; - a system formed by a gas and two different liquids.

The object of the present invention applies to any dispersion as defined above, and more particularly to the systems listed without limitation.

At this stage, it is important to define the terms "emulsifier" and "stabilizer".

In the context of the present invention, the term "emulsifier" denotes a compound which lowers the interfacial tension between two immiscible phases (for example water / oil) and thus allows a large increase in the specific surface of the phase to be emulsified. Thus, the mechanical energy required to form the dispersion is reduced.

The emulsifier may or may not subsequently stabilize the emulsion in a lasting manner by bringing, for example, charges to the surface of the droplets "electrostatic stabilization".

By "stabilizer" is meant any compound which will slow down or even inhibit the phenomena of destabilization of the emulsion or of the dispersion, that is to say the creaming or the flocculation which lead sooner or later to the coalescence of the droplets. or the coagulation of solids in a dispersion. The stabilizer can exercise its function in different ways:

- either by adsorbing on the surface of the droplets without necessarily lowering their interfacial tension and by stabilizing them sterically, - Either by structuring and viscosating the medium so that the speed of creaming of the droplets or the flocculation of the solids is slowed down.

It can thus be said that the stabilizer exercises its function by forming a kind of mechanical barrier preventing the droplets from cremating or the solids from flocculating. Stabilization and emulsification are therefore two distinct but complementary functions.

It should be noted that the operating conditions, such as for example the nature of the phases, the concentration, the pH, the ionic strength, the temperatures, etc., favoring the action of an emulsifier, do not necessarily favor that of a stabilizer. . Thus, many compounds are known for their function as an emulsifier or as a stabilizer. Fewer are those who optimally perform both functions at the same time, at low concentrations and for a large number of different systems.

By way of indication, mention may be made of xanthan gum, carrageenans, alginates or carboxymethylcelluloses, polysaccharides which are known as stabilizers for emulsions but not as emulsifier.

A counter example is gum arabic which has an emulsifying and stabilizing power but this at high concentrations.

However, the Applicant has unexpectedly and surprisingly found that the essentially amorphous cellulose nanofibrils whose crystallinity rate is less than or equal to 50% have remarkable emulsifying and / or stabilizing properties.

Said nanofibrils according to the invention can be both an emulsifier and / or stabilizer in 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 characteristics of the present invention will appear more clearly on reading the description and the examples which follow.

The present invention therefore relates to the use of essentially amorphous cellulose nanofibrils having a crystallinity rate of less than or equal to 50%, as an emulsifying and / or stabilizing agent for a dispersion.

More particularly, the subject of the invention is the use of essentially amorphous cellulose nanofibrils having a crystallinity rate of less than or equal to 50%, as an emulsifying and stabilizing agent for a dispersion. In the present invention, the nanofibrils are used in an amount sufficient to emulsify and / or stabilize.

In particular, the nanofibrils can be present in an amount of between 0.01 and 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 between 0.05 to 1% by weight, preferably between 0.1 and 0.8% by weight relative to the total weight of the dispersion.

By essentially amorphous, we mean nanofibrils whose crystallinity rate is less than or equal to 50%. According to a particular variant of the present invention, the degree of crystallinity is between 15% and 50%. Preferably, the degree of crystallinity is less than 50%.

The cellulose nanofibrils used in the composition of the formulation according to the present invention come from cells preferably made up of at least about 80% of primary walls.

We have such characteristics with cellulose based on parenchyma cells. For example, citrus fruits, such as lemons, grapefruits in particular, or even sugar beet, are plants comprising such cells.

Preferably, the quantity of primary walls is at least 85% by weight. More particularly, cellulose from the sugar beet pulp is used.

According to a preferred variant, the nanofibrils of the invention have at least 80% of cells with primary walls.

The nanofibrils are advantageously loaded at the surface with carboxylic acids and acidic polysaccharides, alone or as a mixture.

By carboxylic acids is meant simple carboxylic acids, 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 their salts. Mention may be made, as acidic polysaccharides, of pectins, which are more particularly polygalacturonic acids. These acidic polysaccharides can be present in mixture with hemicelluloses.

A very advantageous embodiment of the invention consists of nanofibrils whose surface is at least loaded with galaturonic acid and / or polygalacturonic acid.

It should be noted that this is not a simple mixture between said nanofibrils and the acids and polysaccharides, but rather a close combination between these two types of compounds. Indeed, the process for preparing nanoofibrils is such that the acids and polysaccharides are not completely separated from the fibers but still remain on the surface of the latter, giving them very specific properties. Thus, it has been found that it was not possible to obtain the same properties if these acids and / or polysaccharides were completely separated from the nanofibrils during their preparation to be added thereafter. The cellulose nanofibrils also have a section of between approximately 2 and approximately 10 nm. More particularly, the section of the microfibrils is between approximately 2 and approximately 4 nm.

The particular microfibrils used in the composition of food formulations have such characteristics due to the implementation of a very specific preparation process, which will now be described.

It should be noted that this process is, inter alia, the subject of patent application EP 726 356, to which reference may be made for more details.

First of all, said process is more particularly carried out on sugar beet pulp after it has undergone a step of prior extraction of sucrose, according to the methods known in the art.

The preparation process comprises the following stages: (a) first acid or basic extraction, at the end of which a first solid residue is recovered, (b) possibly a second extraction carried out under alkaline conditions from the first solid residue, following from which, a second solid residue is recovered,

(c) washing the first or second solid residue,

(d) optionally bleaching the washed residue,

(e) diluting the third solid residue obtained at the end of step (d) so as to obtain a dry matter content of between 2 and 10% by weight,

(f) homogenization of the diluted suspension.

In step (a), the term "pulp" means moist, dehydrated pulp, preserved by silage or partially defected.

The extraction step (a) can be carried out in an acid medium or in a basic medium. For an acid extraction, the pulp is suspended in a solution of water for a few minutes so as to homogenize the acidified suspension at a pH between 1 and 3, preferably between 1, 5 and 2.5.

This operation is carried out 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 which may be present in the pulp, and which, because of their significant abrasive nature, can cause difficulties in the homogenization step.

For basic extraction, the pulp is added to an alkaline solution of a base, for example sodium hydroxide or potassium hydroxide, of concentration less than 9% by weight, more particularly less than 6% by weight. Preferably, the concentration of the base is between 1 and 2% by weight.

We can add a small amount of a water-soluble antioxidant, such as sodium sulfite Na2Sθ3, in order to limit the cellulose oxidation reactions. 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. During step (a), a partial hydrolysis takes place with release and solubilization of most of the pectins and hemiceltuloses, while preserving the molecular mass of the cellulose.

The solid residue is recovered from the suspension originating from stage (a) using known methods. Thus, it is possible to separate the solid residue by centrifugation, by vacuum or pressure filtration, with filter cloths, or filter presses for example, or by evaporation.

The first solid residue obtained is optionally subjected to a second extraction step, carried out under alkaline conditions.

A second extraction step is carried out when the first has been carried out under acidic conditions. If the first extraction was carried out under alkaline conditions, the second step is only optional.

According to the method, this second extraction is carried out with a base preferably chosen from soda or potash, the concentration of which 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. It is preferably equal to approximately 2 hours.

At the end of this second extraction, if it takes place, a second solid residue is recovered.

In step (c) the residue from step (a) or (b) is washed thoroughly with water in order to recover the residue of cellulosic material.

The cellulosic material of step (c) is then optionally bleached, in step (d), according to conventional methods. For example, treatment can be carried out with sodium chlorite, sodium hypochlorite, hydrogen peroxide at a rate of 5-20% relative to the amount of dry matter treated. Different concentrations of bleach 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 approximately 1 hour and approximately 4 hours, preferably between approximately 1 and approximately 2 hours. A cellulosic material is then obtained containing between 85 and 95% by weight of cellulose.

At the end of this bleaching step, it may be preferable to wash the cellulose thoroughly with water. The resulting suspension, optionally bleached, is then rediluted in water at a rate of 2 to 10% of dry matter, then undergoes a homogenization step. This corresponds to a mixing, grinding or any high mechanical shearing operation, followed by one or more passages of the cell suspension through a small diameter orifice, subjecting the suspension to a pressure drop of at least 20 MPa and to a shearing action at high speed followed by a deceleration impact at high speed.

The mixing or grinding is, for example, carried out by passage (s) in the mixer or grinder for a period ranging from a few minutes to about an hour, in a device of the type such as a WARING BLENDOR equipped with a four-blade propeller or grinder grinding wheel or any other type of grinder, such as a colloid mill.

The actual homogenization will advantageously be 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. We can also cite the MICRO FLUIDIZER which is a homogenizer mainly consisting of a compressed air motor which creates very high pressures, an interaction chamber in which the homogenization operation takes place (elongational shear, shocks and cavitations) and a low pressure chamber which allows the depressurization of the dispersion. The suspension is introduced into the homoqénéisseur preferably after preheating at a temperature ranging between 40 and 120 ° C, preferably ranging between 85 and 95 ° C.

The temperature of the homogenization operation is maintained between 95 and 120 ° C, preferably above 100 ° C. The suspension is subjected in the homogenizer to pressures between 20 and 100 MPa, and preferably greater than 50 MPa.

The homogenization of the cellulosic suspension is obtained by a number of passages which can vary between 1 and 20, preferably between 2 and 5, until a stable suspension is obtained. The homogenization operation can advantageously be followed by a high mechanical shearing operation, for example in a device such as the ULTRA TURRAX from SYLVERSON.

It should be noted that this process has been described in European patent application EP 726 356 filed on 07/02/96, reference may therefore be made to it if necessary. Example 20 of this text gives in particular a method of preparing a suspension of essentially amorphous cellulose nanofibrils.

In the context of the present invention, the nanofibrils can be used in the form of an aqueous suspension, as obtained by the process described above. According to a particular embodiment of the invention, the cellulose nanofibrils can be associated with at least one polyhydroxylated organic compound (polyOH).

More particularly, the polyhydroxy compound (polyOH) is chosen from carbohydrates and their derivatives, and polyols. With regard to carbohydrates, mention may be made particularly of linear or cyclic monosaccharides in C-3 to C-6, and preferably in C-5 or C- 6, oligosaccharides, polysaccharides and their fatty derivatives such as fatty acid sucroesters or sucroesters, alcohol carbohydrates and mixtures thereof. By way of nonlimiting examples of the monosaccharides, fructose, mannose, galactose, glucose, talose, gulose, allose, altrose, idose, arabinose, xylose, lyxose are suitable. and ribose.

Mention may be made, as oligosaccharides, inter alia, of sucrose, maltose and lactose. The polysaccharides can be of animal, plant or even bacterial origin.

In addition, they can be used in an anionic or nonionic form.

Xanthaπe gum, succinoglycans, carrageenans, alginates are representative elements of anionic polysaccharides.

With regard to nonionic polysaccharides, mention may in particular be made of galactomannans, such as guar gum, locust bean gum, starch and its nonionic derivatives, nonionic cellulose derivatives.

As for the carbohydrate derivatives, there may be mentioned without intending to be limited thereto, the fatty acid sucroesters, the fatty acid esters, the carbohydrates of sorbitol-type alcohols, mannitol; carbohydrates of acids such as gluconic acid, uronic acids, such as galacturonic acid, glucuronic acid, as well as their salts, and carbohydrates of ethers such as carboxymethylated cellulose. As regards polyols, it is possible to use in food formulations, glycerol, pentaerythritol, propylene glycol, ethylene glycol and or polyvinyl alcohols.

It should be noted that the compounds described above can be used alone or as a mixture. When this particular embodiment is implemented, the polyhydroxylated organic compound (s) (polyOH) (s) is associated with the cellulose nanofibrils in a weight ratio (polyOH) ( s) x 100 / [(polyOH) (s) + (NFC)] between 5 and 50%, and preferably between 5 and 30%. Quite advantageously, this ratio is between 10 and 30% and preferably between 15 and 30% by weight.

According to a first particularly advantageous variant, the polyhydroxylated compound is at least carboxymethylee cellulose. Cellulose is a polymer made up of monomeric units of glucose. The carboxyl group is introduced in a manner known per se, by reacting chloroacetic acid with cellulose.

The degree of substitution corresponds to the number of carboxymethyl groups per unit of glucose. The maximum theoretical degree is 3. Depending on whether the degree of substitution is greater than 0.95, or less than or equal to this value, it is specified that the carboxymethylee cellulose is, respectively, at high or at low degree of substitution. Preferably, the carboxymethylcellulose has a degree of substitution is greater than 0.95.

According to a second variant, the polyhydroxylated 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 such as carbohydrates alcohols, acids and ethers.

In particular, the carboxymethylee cellulose is used in combination with at least one of the following compounds: xanthan gum, sorbitol, sucrose.

Optionally, the cellulose nanofibrils can be combined, in addition to the aforementioned polyhydroxy compound, with at least one co-additive chosen from:

° the carboxylated cellulose having a degree of substitution less than or equal to 0.95, preferably carboxymethylated cellulose, ^π the osidic monomers or oligomers,

° the compounds of formula (R1R2N) C0A, formula in which R1 or R2, identical or different, represent hydrogen or an alkyl radical in C-1 to C-

10, preferably at C-1 to C-5, A represents hydrogen, an alkyl radical at C- 1 to C-10, preferably at C-1 to C-5, or also the group R "iR ' 2N with R ' ¹ ,

R'2, identical or different, representing hydrogen or a C-1 to C-10, preferably C-1 to C-5, alkyl radical,

° cationic or amphoteric surfactants.

As regards the compounds of the (RtR2N) COA type, it is preferred to use the compounds comprising two amide functions. Preferably urea is used as a co-additive. The cellulose nanofibrils falling within the scope of the present invention result from the drying of a dispersion of nanofibrils, preferably in the presence of an additive and optionally a co-additive.

Thus, the cellulose nanofibrils of the present invention can be used in dry dispersible form.

Another object of the present invention is the use of nanofibrils according to the invention, where appropriate in combination with an additive, and optionally a co-additive as an emulsifying and / or stabilizing agent in the fields of cosmetics, food, concrete constructions, drilling fluids, radical polymerization such as direct or reverse emulsion polymerization, microemulsion, suspension, dispersion ...

The subject of the invention is also compositions in the fields of cosmetics, food, concrete constructions, drilling fluids, or compositions based on polymer resulting from a radical polymerization, comprising nanofibrils according to the invention, where appropriate in combination with an additive, and optionally a co-additive, as an emulsifying and / or stabilizing agent.

Concrete but nonlimiting examples of the invention will now be presented.

EXAMPLES Example 1

This example relates to the preparation of cellulose nanofibrils (NFC) in the form of mother suspension, and in dry form comprising carboxymethylcellulose (CMC).

1. Preparation of the mother dispersion of nanofibrils:

The mother dispersion of cellulose nanofibrils is obtained according to the process described in Example 20 of patent application EP 726 356; it comprises 2.3% of cellulose nanofibrils and is prehomogenized with Ultra-Turrax at 14,000 rpm -1 min for 100 g of dispersion).

2. Preparation of dried nanofibrils comprising carboxymethylcellulose (CMC)

The mother dispersion of cellulose nanofibrils is obtained according to the process described in Example 20 of patent application EP 726 356; she understands 2.3% in cellulose microfibrils and is prehomogenized with Ultra-Turrax at 14,000 rpm - 1 min for 100 g of dispersion).

The carboxymethylcellulose used has a degree of substitution equal to 1, 2; medium viscosity (BLANOSE 12M8P product from AQUALON). The CMC is dissolved in distilled water and then added to the mother dispersion of (NFC) and the whole is stirred with a deflocculating paddle at 1000 rpm for 30 min.

The amount of carboxymethylcellulose added is 30% relative to the weight of CMC. The mixture is then poured into cups and then dried in a ventilated oven at 40 ° C, to a dry extract of 77%, controlled by dosing the water using an infrared thermobalance.

The dried mixture is then ground in a coffee grinder, then sieved through a 500 μm sieve.

Example 2

The purpose of this example is to demonstrate the emulsifying power of cellulose nanofibrils (NFC).

1. Measurement of surface tension (water / air)

The surface tensions are measured with a KREUSS automatic tensiometer (Type K 14) and a WILHELMY blade.

Measurement of the surface tension of cellulose nanofibrils without additive (mother dispersion): The cellulose nanofibrils are predispersed with moderate stirring in distilled water in order to have a mass concentration of 0.28%. This dispersion is then stirred for 15 minutes at 1000 rpm, then homogenized at atmospheric pressure with Ultra Turrax for 2 minutes at 13500 rpm.

A control of the water quality and the cleanliness of the equipment makes it possible to check the theoretical value of the surface tension of the distilled water of 71.1 mN / m at 23 ° C.

50 ml of dispersion are placed in a crystallizer of the tensiometer and left to stand for 30 minutes. The platform is then raised to immerse the blade. 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 with moderate stirring 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 with Ultra Turrax for 2 minutes at 13500 rpm.

The measurement of the surface tension is carried out as previously.

Comparative Test: Measurement of the surface tension of carboxymethylcellulose

(CMC) The dry CMC powder (the references of which are given in Example 1) is predispersed with moderate stirring 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 with Ultra Turrax for 2 minutes at 13500 rpm. The surface tension measurement is carried out as above (cf.

Table I).

Comparative Test: Measurement of the surface tension of gum arabic

The gum arabic is predispersed with moderate stirring 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 with Ultra Turrax for 2 minutes at 13500 rpm.

The surface tension measurement is carried out as above (see Table I).

2. Measurement of interfacial tension (water / oil)

The interfacial tensions are measured with a hanging dropper of the LAUDA TVT11 type.

No calibration is necessary with this device, only a prior check of the cleanliness of the water must be carried out.

The principle of handling 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 oil 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, the value of which can be linked to the interfacial tension. The measurements are carried out in quasi-static mode, in order to allow the emulsifying agent time to migrate to the interface. The interfacial tension values are determined after an equilibrium time of 30 minutes.

The results collated in Table I show that NFCs significantly lower the surface and interfacial tensions of oils of very different polarity.

Table I

The results of Table I clearly show that NFCs have an emulsifying power.

(in terms of interfacial and surface tension) comparable to gum arabic, but at much lower concentrations than gum arabic.

Example 3 The purpose of this example is to demonstrate the stabilizing power of cellulose nanofibrils (NFC).

For this, oil in water emulsions (m / w) were prepared and measured in droplet size by particle size and light microscopy. Preparation of emulsions

The dispersions of NFCs optionally additive are carried out in distilled water at the required concentration as in Example 2.

The appropriate amount of soybean oil (RISSO brand) or n-hexadecane (from MERCK) is then added to the water phase (30% by mass relative to the aqueous phase) and the whole is prehomogenized with a homogenizer of Ultra type. Turrax IKA T25 for 1 minute at 9500 rpm.

This prehomogenization is intended to guarantee a uniform passage through the Microfluidizer. In fact, 1 pass is made to the M 110T microfluidizer at 500 bars: the emulsions obtained are beautiful, homogeneous and stable over time.

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

Characterization of emulsions

The granulometry is determined by laser granulometry (HORIBA device of reference LA 910) and by optical microscopy (OLYMPUS device of reference BH-2). The measurements are taken immediately after emulsification, then at the regular interval after storage.

The values of the mean diameters appearing in Table II show that the use of NFC makes it possible to obtain stable emulsions of relatively tight particle size.

No stable emulsion could be obtained with CMC because the emulsions coalesce immediately after homogenization.

Table II: Evaluation of soybean oil, hexadecane and silicone emulsions

^* D corresponds to the average diameter in μm.

^* l corresponds to the polydispersity index: the closer I is to 1 the more the droplets are monodisperse.

Example 4

The purpose of this example is to show that the NFCs together with the CMC as an emulsifying and stabilizing agent can lead to obtaining a multiple water in oil in water (w / w / w) emulsion, of relatively narrow particle size, of 50 microns and stable over time.

Composition soybean oil 30% city water 48% vinegar at 12% 13% sugar 6%

NaCI 2.5%

NFC / CMC 0.5% Procedure

The sugar is then added with stirring at 500 rpm, then the NFC / CMC with water. The stirring is brought to 1000 rpm and is maintained for 15 min. Then add the vinegar and salt and keep stirring for 3 minutes.

The oil is then added and the whole is stirred for 3 minutes.

The whole is homogenized first for 1 minute at 9500 rpm with the Ultra Turrax IKA T25, and then by passing to the Microfluidizer M 110T at 500 bars.

A beautiful, homogeneous and stable w / o / w emulsion over time is obtained.

Claims

1. Use of essentially amorphous cellulose nanofibrils having a crystallinity rate less than or equal to 50%, as an emulsifying and / or stabilizing agent for a dispersion.

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

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

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

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

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

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

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

9. Use according to any one of claims 1 to 8, characterized in that the nanofibrils are present in an amount between 0.01 to 5% by weight relative to the total weight of the dispersion.

10. Use according to one of claims 8 or 9, characterized in that the nanofibrils are present in an amount between 0.05 to 1% by weight, preferably between 0.1 and 0.8% by weight relative to the total weight of the dispersion.

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

12. Use according to any one of claims 1 to 11, characterized in that the nanofibrils come from cells made up of at least 80% of primary walls.

13. Use according to any one of claims 1 to 12, characterized in that the cellulose nanofibrils have at least 80% of cells with primary walls.

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

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

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

18. Use according to any one of claims 1 to 17, characterized in that the cellulose nanofibrils, and where appropriate the polyhydroxylated organic compound (polyOH), are associated with at least one co-additive chosen from:

° the carboxylated cellulose having a degree of substitution less than or equal to 0.95, preferably carboxymethylated cellulose,

° the osidic monomers or oligomers,

10, preferably at C-1 to C-5, A represents hydrogen, a C- 1 to C-10, preferably C-1 to C-5 alkyl radical, or alternatively the group R ' ¹ R '2N with R' ¹ ,

R'2, identical or different, representing hydrogen or an alkyl radical in C-1 to C-10, preferably in C-1 to C-5, ^α cationic or amphoteric surfactants. these co-additives being used alone or as a mixture.

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

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

21. Use of nanofibrils according to any one of claims 1 to 14, if necessary in combination with an additive according to any one of claims 15 to

17 and optionally a co-additive according to claim 18, as an emulsifying and / or stabilizing agent in the fields of cosmetics, food, concrete constructions, drilling fluids, radical polymerization.

22. Composition in the fields of cosmetics, food, concrete constructions, drilling fluids, or compositions based on polymer resulting from a radical polymerization, comprising nanofibrils according to any one of claims 1 to 14 if necessary in combination with an additive according to any one of claims 15 to 17 and optionally a co-additive according to claim 18 as an emulsifying and / or stabilizing agent.