FR3045609A1 - METHOD OF PURIFYING POLYROTAXANES BASED ON CYCLODEXTRINS - Google Patents

Abstract

The subject of the invention is a method for purifying a polyrotaxane based on cyclodextrins comprising, as impurities, free cyclodextrins, which comprises the following steps: a) heat treatment at a temperature ranging from 70 to 300 ° C. of the polyrotaxane based on cyclodextrins comprising, as impurities, free cyclodextrins, and then b) dissolving the product obtained in step a) in a solvent in which the polyrotaxane based on cyclodextrins comprising, as impurities, free cyclodextrins is soluble before the heat treatment, then c) a possible step of sonication by means of ultrasound of the solution obtained in step b), then d) elimination of the insoluble constituents of the solution obtained in step c), e) possible drying of the solution obtained in step d).

Description

METHOD OF PURIFYING BASED POLYROTAXANES

CYCLODEXTRINS

The present invention relates to a method for purifying a polyrotaxane based on cyclodextrins comprising as impurities free cyclodextrins, this method comprising in particular a heat treatment step.

Polyrotaxanes are supramolecular assemblies consisting of cyclic molecules threaded along polymer chains which have at their ends bulky groups avoiding the unwinding of the cyclic molecules.

Polyrotaxanes are assemblies which, introduced into a material, give it interesting properties, such as, for example, abrasion resistance (see, in particular, patent application EP2397527).

During the preparation of these assemblies, the stripping of the cyclic molecules can be important. At the end of the preparation, it is therefore usual to obtain a mixture consisting of a polyrotaxane and free cyclic molecules. It is then essential to effectively remove the free cyclic molecules present in the product since they can alter the mechanical properties of the polyrotaxane by the presence of crystalline zones for example.

The cyclic molecules strung onto the polyrotaxane may be in particular of the family of cyclodextrins.

The purification of a polyrotaxane based on cyclodextrins is difficult, in particular because of the hydrogen bonds that can form between the hydroxyl functions carried by the free cyclodextrins and the hydroxyl functions carried by the cyclodextrins strung onto the polymer chain of the polyrotaxane.

One purification route is to modify the hydroxyl groups of the cyclodextrins to minimize the interactions between the free and strung cyclodextrins.

Typically, this consists first of all in carrying out, for example, acetylation, alkylation, benzoylation, benzylation, halogenation, methylation, sulfonylation or silylation of the hydroxyl functions of the cyclodextrins.

Then, the polyrotaxane and the free cyclodextrins are separated.

Finally, the hydroxyl functions of the cyclodextrins of the polyrotaxane are restored.

However, this purification route is particularly expensive because of the number of steps to be implemented and the cost of the chemicals. In addition, because of the large number of steps, the purification efficiency is low which also increases the cost.

Another method is to purify the polyrotaxane based on cyclodextrins using the technique of preparative steric exclusion chromatography.

However, this purification method is particularly long and is not applicable to large quantities of product to be purified. In particular, the purification columns are expensive and are rapidly saturated. Therefore, it is necessary to clean them often to regenerate which represents an additional cost. In addition, purification on such columns requires large amounts of solvent which must then be evaporated from the sample which, with low volatility solvents, is difficult, long and therefore expensive.

Therefore, there is a need to develop a new method for purifying a cyclodextrin-based polyrotaxane comprising as impurities free cyclodextrins, which is simple to implement, effective, and which allows to quickly obtain large amounts of purified cyclodextrin polyrotaxane.

The applicants have now discovered that a purification method associating a heat treatment and a dissolution in solution allowed to respond perfectly to the technical problem posed. The subject of the invention is therefore a method for purifying a polyrotaxane based on cyclodextrins comprising, as impurities, free cyclodextrins, which comprises the following steps: a) heat treatment at a temperature ranging from 70 to 300 ° C. polyrotaxane based on cyclodextrins comprising free cyclodextrins as impurities, then b) dissolving the product obtained in step a) in a solvent in which the cyclodextrin-based polyrotaxane comprising, as impurities, free cyclodextrins; is soluble before the heat treatment, then c) removal of the insoluble constituents of the solution obtained in step b).

The method according to the invention is simple to implement, effective, and allows to obtain quickly at low cost large amounts of polyrotaxane based on cyclodextrins with good purity.

In addition, because of its simplicity of implementation, the method according to the invention can be carried out several times in succession on the same sample of polyrotaxane to obtain a still improved purity. The invention as well as its advantages will be readily understood in the light of the description and examples of embodiments which follow.

In the present description, unless expressly indicated otherwise, all the percentages (%) indicated are% by weight. On the other hand, any range of values designated by the expression "between a and b" represents the range of values from more than a to less than b (i.e., terminals a and b excluded) while any range of values designated by the expression "from a to b" means the range from a to b (i.e., including the strict limits a and b).

In the present invention, the term "rate of recovery of the polymer chain", the percentage by number of cyclodextrins present along the polymer chain relative to the maximum number of threadable cyclodextrins. Thus, 100% recovery of the polymer chain corresponds to the maximum number of insertable cyclodextrins thereon and 60% of the polymer chain recovery ratio means that 60% of the maximum number of insertable cyclodextrins are threaded onto the polymer chain. and that the remaining 40% of cyclodextrins are free.

For the purposes of the present invention, the term "ambient temperature", a temperature ranging from 15 ° C to 25 ° C, and preferably about 20 ° C.

As previously explained, a polyrotaxane is a supramolecular assembly consisting of one or more cyclic molecules threaded along a polymer chain which has at its two ends bulky groups avoiding the unwinding of the cyclic molecules.

The polymer chain is generally chosen from polyvinyl alcohols, poly (meth) acrylic acids, cellulose-based polymers such as carboxymethylcellulose, hydroxyethylcellulose and hydroxypropylcellulose, polyacrylamides, poly (ethylene oxides), poly (propylene oxides), polymers based on poly (vinyl acetate), poly (vinyl methyl ethers), polyamines, poly (ethylene imines), casein, gelatin, starch, polymers with polyolefin base such as polyethylene, polypropylene and copolymers of ethylene and propylene, polyester polymers, polyvinyl chloride polymers, polystyrene-based polymers, acrylic polymers such as poly (methyl methacrylate) and its copolymers, polycarbonate polymers, polyurethanes, poly (isobutylenes), polytetrahydrofurans, polyanilines, acrylonitrile-b copolymers uradiene-styrene (ABS polymers), polyamides such as nylon, polyimides, diene polymers such as polyisoprene (PI) and polybutadiene (PB), polysiloxanes such as polydimethylsiloxane (PDMS), polysulfones, polyimines poly (acetic anhydrides), polyureas, polysulfides, polyphosphazenes, poly (ketones), polyphenylenes, polyhalo-olefins, and copolymers and / or blends of these polymers.

By diene polymer, whether natural or synthetic, must be understood in known manner an elastomer consisting at least in part (ie, a homopolymer or a copolymer) of monomeric units dienes (monomers bearing two carbon-carbon double bonds, conjugated or not).

These diene elastomers can be classified into two categories "essentially unsaturated" or "essentially saturated". The term "essentially unsaturated" is generally understood to mean a diene elastomer derived at least in part from conjugated diene monomers, having a proportion of units or units of diene origin (conjugated dienes) which is greater than 15% (mol%); Thus, diene elastomers such as butyl rubbers or copolymers of dienes and alpha-olefins of the EPDM type do not fall within the above definition and may in particular be described as "essentially saturated" diene elastomers ( low or very low diene origin, always less than 15%). In the category of "essentially unsaturated" diene elastomers, the term "highly unsaturated" diene elastomer is particularly understood to mean a diene elastomer having a content of units of diene origin (conjugated dienes) which is greater than 50%.

Preferably, the polymer chain is chosen from poly (ethylene oxides), poly (propylene oxides), poly (ethylene oxide) copolymers, poly (propylene oxide) copolymers, polyesters. (isobutylenes), polydimethylsiloxane (PDMS), diene polymers such as polyisoprene (PI), polybutadiene (PB), styrene-butadiene copolymers (SBR), styrene-isoprene copolymers (SIR), and copolymers ethylene-propylene-diene monomer (EPDM), polyolefin-based polymers such as butene-ethylene (EBR) copolymers, and mixtures of these polymers.

In a very particularly preferred manner, the polymer chain is chosen from poly (ethylene oxides), poly (isobutylenes), and mixtures of these polymers.

The large groups at both ends which prevent the stripping of the cyclic molecules are generally bulky groups such as triphenyl, phenalene, phenanthrene, anthracene, fluoranthene, acephenanthrylene, acanthrylene derivatives, triphenylene, pyrene, chrysene, naphthacene, pleiadene, picene, perilene, pentaphene, pentacene, phthalocyanine, cyclodextrin, di- or tri-adamantane, cucurbituril, or crown ether, these bulky groups carrying a function or an activatable group which can react with the polymer chain such as halogen, carboxyl, hydroxyl, amine, isocyanate, thioisocyanate, double bond, aldehyde, amide or azide .

Particularly preferably in the invention, the bulky groups are pyrene derivatives.

In the present invention, the polyrotaxane is based on cyclodextrins.

Cyclodextrin means cyclic oligosaccharides composed of α- (1,4) -linked glucopyranose subunits.

Preferably, the cyclodextrins used in the method according to the invention are chosen from α-cyclodextrins (6 glucopyranose subunits), β-cyclodextrins (7 glucopyranose subunits), γ-cyclodextrins (8 subunits). glucopyranose), δ-cyclodextrins, ε-cyclodextrins, and derivatives of these compounds.

In a particularly preferred manner, the cyclodextrins used in the method according to the invention are chosen from α-cyclodextrins, γ-cyclodextrins, and derivatives of these compounds.

The choice of the type of cyclodextrin used generally depends on the polymer chain used for the polyrotaxane, in particular their respective sizes, namely the diameter of the polymer chain with respect to the size of the cavity of the cyclodextrin.

Thus, for a polymer chain chosen from poly (ethylene oxides) for example, preference will be given to α-cyclodextrins. Similarly, for a polymer chain chosen from poly (isobutylenes) for example, preference will be given to γ-cyclodextrins.

Preferably in the present invention, the cyclodextrins are chosen from cyclodextrins with unmodified hydroxyl groups, cyclodextrins with partially or totally silylated hydroxyl groups and cyclodextrins with partially substituted hydroxyl groups by means of groups other than silyl groups. .

Cyclodextrins with partially substituted hydroxyl groups by means of groups other than silyl are, for example, acetylated, alkylated, benzoylated, benzylated, halogenated, methylated and sulfonylated cyclodextrins.

For cyclodextrins with partially or completely silylated hydroxyl groups, the silyl groups are, for example, chosen from trimethylsilyl, tert-butyldimethylsilyl, triisopropylsilyl or tert-butyldiphenylsilyl.

Thus, in a particularly preferred manner, the cyclodextrins used in the method according to the invention are chosen from unmodified α-, γ-cyclodextrins, α-, γ-cyclodextrins with partially substituted hydroxyl groups by means of groups other than silyls and α-, γ-cyclodextrins with hydroxyl groups partially or completely silylated.

Most preferably, the cyclodextrins used in the method according to the invention are chosen from unmodified α-, γ-cyclodextrins and α-, γ-cyclodextrins with partially or completely silylated hydroxyl groups.

As stated above, the first step of the method according to the invention is a heat treatment at a temperature ranging from 70 to 300 ° C of the cyclodextrin-based polyrotaxane comprising free cyclodextrins as impurities.

This heat treatment step makes it possible to render the free cyclodextrins insoluble while maintaining the polyrotaxane based on cyclodextrins soluble, in a solvent in which the cyclodextrin-based polyrotaxane comprising as impurities free cyclodextrins is soluble before heat treatment.

Thus, the skilled person will be able to choose the temperature in the claimed range depending on the duration of this step and vice versa. Indeed, it is well known to those skilled in the art that the higher the temperature of a reaction increases and the duration of this reaction is short. Conversely, the lower the temperature of a reaction is and the longer the duration of this reaction should increase.

However, preferably, the heat treatment step a) is carried out at a temperature ranging from 100 ° C to 250 ° C, and more particularly from 140 ° C to 250 ° C.

Thus, with these preferred temperature ranges, the heat treatment step a) generally has a duration ranging from 1 millisecond to 24 hours, preferably from 10 minutes to 4 hours.

This step usually takes place at atmospheric pressure.

For this step, an oven, an oven with an inert or non-inert atmosphere, or a heating plate is generally used.

The product obtained in step a) is then dissolved in a solvent in which the cyclodextrin-based polyrotaxane comprising, as impurities, free cyclodextrins is soluble before the heat treatment. As solvents in which the cyclodextrin-based polyrotaxane comprising, as impurities, free cyclodextrins is soluble before the heat treatment, mention may notably be made of water, ethanol, dimethylformamide (DMF) and dimethylsulfoxide (DMSO) ).

Therefore, preferably, the solvent of solution solution step b) is selected from water, ethanol, dimethylformamide (DMF), dimethylsulfoxide (DMSO), and a mixture of these solvents.

The amount of solvent must generally be adapted to the amount of products obtained in the heat treatment step a).

However, preferably, the concentration of the product obtained in the heat treatment step a) in the solvent of the dissolution stage b) is from 0.1 g / l to 150 g / l, preferably from 0.1 g / L to 20 g / L.

In a particularly preferred manner, the method according to the invention further comprises, between step b) and step c), a step of sonication, preferably by means of ultrasound, of the solution obtained in step b ).

By sonication by means of ultrasound within the meaning of the present invention, it is meant that the liquid sample is subjected to ultrasound (in a range typically between 20 kHz and 400 kHz). Thus, polyrotaxanes based on cyclodextrins are generally more easily solubilized in the chosen solvent and the free cyclodextrins are insoluble and remain in suspension in the solvent.

Preferably, the sonication step has a duration ranging from 1 minute to 24 hours, preferably from 15 minutes to 24 hours. Generally, the sonication step is carried out at a temperature ranging from 10 ° C to 80 ° C depending on the chosen solvent.

However, the sonication step is preferably carried out at room temperature.

This step usually takes place at atmospheric pressure.

As stated above, step c) of the method according to the invention is an elimination of the insoluble constituents of the solution obtained in step b) or optionally of the solution obtained after the sonication step.

Preferably, the elimination step c) is carried out by centrifugation or by filtration, and preferably is carried out by centrifugation. The elimination step c) is preferably carried out at room temperature.

Preferably, the elimination step c) has a duration ranging from 1 min to several hours, and preferably from 10 min to 1 hour.

When the elimination step c) is carried out by centrifugation, the relative centrifugal force (RCF) is generally between 100 g and 300 000 g, preferably between 1000 g and 30 000 g.

The method according to the invention may further comprise a step of drying the solution obtained in the elimination step c).

This step consists of removing the residual solvent and recovering the purified polyrotaxane in dry form.

It is preferably carried out under reduced pressure, which makes it possible to evaporate the solvent at moderate temperatures relative to the boiling point of the solvent and at atmospheric pressure.

Reduced pressure within the meaning of the present invention means a pressure preferably less than 1 bar, more preferably less than 1 mbar, and even more preferably less than 10'3 mbar.

This drying step, when carried out under reduced pressure, is preferably carried out at a temperature ranging from 0 ° C to 70 ° C, preferably from 0 ° C to 50 ° C.

In a particularly preferred manner, this step, when it is carried out under reduced pressure, is carried out at room temperature.

It can also be carried out under atmospheric pressure at a temperature, in this case, generally higher.

The temperature then generally varies from the freezing temperature to the boiling point of the solvent in the case where it is desired to proceed at atmospheric pressure, without exceeding the temperature of the heat treatment.

In a particularly preferred embodiment of the invention, the purification method according to the invention comprises the following steps: a) heat treatment at a temperature ranging from 100 ° C. to 250 ° C., preferably from 140 ° C. to 250 ° C. for 1 ms to 24 hours, preferably for 10 minutes to 4 hours, at atmospheric pressure, polyrotaxane based on cyclodextrins comprising free cyclodextrins as impurities, then b) solution of the product obtained in step a) in a solvent in which cyclodextrin-based polyrotaxane comprising as free impurities free cyclodextrins is soluble before the heat treatment, the concentration of the product obtained in step a) in the solvent of step b) going from 0.1 g / l to 150 g / l, preferably from 0.1 g / l to 20 g / l and then c) sonication using ultrasound of the solution obtained in step b) during a duration ranging from 1 minute to 24 hours, preferably from 15 minutes to 24 hours at room temperature and at atmospheric pressure, then d) removal of the insoluble constituents of the solution obtained in step c) by centrifugation at room temperature, for a period ranging from 1 min to several hours, preferably from 10 min to 1 hour with a relative centrifugal force (RCF) of between 100 g and 300 000 g, preferably between 1000 g and 30 000 g, then e) drying the solution obtained in step d) under reduced pressure at room temperature to recover the polyrotaxane purified.

The method according to the invention can be used several times in succession in order to increase the degree of purity of the polyrotaxane.

Examples

Size exclusion chromatography

The products obtained by the method according to the invention are analyzed by size exclusion chromatography in dimethylformamide (DMF). The chromatography column used is WATERS (WAT045810) and is coupled to a UV detector (λ = 345 nm) and a refractometric detector. Chromatography is performed at a flow rate of 0.3 ml / mm and the injection volume is 50 μl (concentration 1 mg / ml). After calibration, this method of quantification of free cyclodextrins (for details on the quantification method, see in particular the document Macromolecular Chemistry and Physics, 205, 1206-1217 (2004), "A new versatile radical addition on α, ω- poly (ethylene oxide) dimethacrylate) makes it possible to obtain results very close to the method of direct quantification of polyrotaxane conversion by residue assay (free cyclodextrins).

EXAMPLE 1 Purification of a Polyrotaxane Based on Poly (Ethylene Oxide) and a-Cyclodextrin

For synthesis, see also the document cited above, a polyrotaxane based on a poly (ethylene oxide) (number average mass = 58,800 g / mol) and α-cyclodextrins has been synthesized. in that the recovery rate of the α-cyclodextrin polymer chain is 74%. There remains 26% of free α-cyclodextrins in the sample. The large groups at the end of the chains are here pyrene derivatives. 1 mg of the sample is subjected to a heat treatment at a temperature and for a determined duration (see Table 1 below) at atmospheric pressure. The sample is then dissolved in water at a level of 1 g / l. Then, the sample is sonicated for 30 minutes at room temperature and at atmospheric pressure. The soluble fraction is then recovered by centrifugation at 18,500 g for 20 minutes at room temperature and then the solution collected is evaporated under vacuum at room temperature until the mass of the sample is constant. The sample is analyzed by size exclusion chromatography. Measuring the peak corresponding to free α-cyclodextrin makes it possible to estimate the amount of residual free α-cyclodextrins in the sample. Comparative sample A was not treated by the above method and corresponds to the starting material (unpurified). The comparative sample B was treated by the above method but at a temperature below the temperature used in the method according to the invention. Sample C illustrates the method according to the invention and was treated by the above method at a temperature within the temperature range used in the method according to the invention.

Table 1 below collates the data for the three samples A, B and C.

Table 1

The purification method according to the invention thus makes it possible to simply and effectively purify a polyrotaxane based on cyclodextrins.

EXAMPLE 2 Purification of a Polyrotaxane Based on Poly (Ethylene Oxide) and a-Cyclodextrin

A polyrotaxane based on a poly (ethylene oxide) (average mass number = 58,800 g / mol) and a-cyclodextrins was synthesized according to the same method as in Example 1, characterized in that the The recovery of the α-cyclodextrin polymer chain is 16%. This leaves 84% of free α-cyclodextrins in the sample. The large groups at the end of the chains are here pyrene derivatives. 13 g of the sample is subjected to a heat treatment at a temperature of 200 ° C and for a period of 15 minutes at atmospheric pressure. The sample is then dissolved in water at a level of 13 g / L overnight (16 hours). Then, the sample is sonicated with ultrasound for 15 minutes at room temperature and at atmospheric pressure. The soluble fraction is then recovered by centrifugation at 18,500 g for 20 minutes at room temperature and then the solution collected is evaporated under vacuum at room temperature until the mass of the sample is constant. The sample is analyzed by size exclusion chromatography. Measuring the peak corresponding to free α-cyclodextrin makes it possible to estimate the amount of residual free α-cyclodextrins in the sample.

Table 2 below collects the data from the comparative D sample that was not processed by the above method and which corresponds to the starting material (non-purified) and the sample E which illustrates the method. according to the invention and which has been treated with the method described above.

Table 2

The purification method according to the invention thus makes it possible to simply and effectively purify a polyrotaxane based on cyclodextrins.

Example 3 Purification of a Polyrotaxane Based on Poly (Isobutylene) and of γ-Cyclodextrin

Using the same method as Example 1 adapted to the polymer of Example 3, a polyrotaxane based on a poly (isobutylene) (number average mass = 400 g / mol) and γ-cyclodextrins characterized by the recovery rate of the γ-cyclodextrin polymer chain is 72%. There remains 28% of free γ-cyclodextrins in the sample. The large groups at the end of the chains are here pyrene derivatives. 0.5 g of the sample is subjected to a heat treatment at a temperature of 150 ° C and for a period of 2 hours. The sample is then dissolved in water at a level of 10 g / l. Then, the sample is subjected to a sonication step by means of ultrasound for 4 hours at room temperature and at atmospheric pressure. The soluble fraction is then recovered by centrifugation at 18,500 g for 20 minutes at room temperature and then the solution collected is evaporated under vacuum at room temperature until the mass of the sample is constant. The sample is analyzed by size exclusion chromatography. Measuring the peak corresponding to the free γ-cyclodextrin makes it possible to estimate the amount of residual free γ-cyclodextrins in the sample.

Table 3 below collates the data from the comparative F sample that was not processed by the above method and which corresponds to the starting material (unpurified) and the sample G illustrating the method. according to the invention and which has been treated with the method described above.

Table 3

The purification method according to the invention thus makes it possible to simply and effectively purify a polyrotaxane based on cyclodextrins.

EXAMPLE 4 Purification of a Polyrotaxane Based on Poly (Ethylene Oxide) and Modified α-Cyclodextrin

A polyrotaxane based on a poly (ethylene oxide) (average mass by number = 58,800 g / mol) and unmodified α-cyclodextrins was synthesized, characterized in that the degree of recovery of the polymer chain in α-cyclodextrins is 16%. 84% of free unmodified a-cyclodextrins remain in the sample (sample D). The large groups at the end of the chains are here pyrene derivatives. This sample is subjected to the purification method according to Example 2 above. A sample having a free cyclodextrin content of 16% (sample E) is thus obtained.

A mixture consisting of 7 mg of sample E and 28 mg of completely silylated α-cyclodextrins is prepared. This mixture is subjected to a heat treatment at a temperature of 200 ° C and for a period of 20 minutes and at atmospheric pressure. The sample is then dissolved in DMF at a content of 17.5 g / l. Then, the sample is sonicated for one hour at room temperature and at atmospheric pressure. The soluble fraction is then recovered by centrifugation at 18,500 g for 20 minutes at room temperature and then the solution collected is evaporated under vacuum at room temperature until the mass of the sample is constant. The sample is analyzed by size exclusion chromatography. Measuring the peak corresponding to free α-cyclodextrin makes it possible to estimate the amount of residual free α-cyclodextrins in the sample.

Table 4 below collates the data of the comparative sample H which was not treated by the above method and which corresponds to the purified polyrotaxane of Example 2 mixed with the totally silylated cyclodextrin free and sample I which illustrates the method according to the invention and which has been treated with the method described above.

Table 4

The purification method according to the invention thus makes it possible to simply and efficiently purify a polyrotaxane based on cyclodextrins, in particular when they are silylated.

Claims (17)

A method of purifying a cyclodextrin-based polyrotaxane comprising free cyclodextrins as impurities, which comprises the following steps: a) heat treating at a temperature ranging from 70 to 300 ° C of the cyclodextrin-based polyrotaxane comprising as impurities of the free cyclodextrins, and then b) dissolving the product obtained in step a) in a solvent in which the polyrotaxane based on cyclodextrins comprising as impurities free cyclodextrins is soluble before the heat treatment and then c) removing the insoluble constituents of the solution obtained in step b). 2. Method according to claim 1, characterized in that the polyrotaxane has a polymer chain, this polymer chain being chosen from polyvinyl alcohols, poly (meth) acrylic acids, cellulose-based polymers such as carboxymethylcellulose, hydroxyethylcellulose and hydroxypropylcellulose, polyacrylamides, poly (ethylene oxides), poly (propylene oxides), polymers based on poly (vinyl acetate), poly (vinyl methyl ethers), polyamines, polyesters ethylene imines, casein, gelatin, starch, polyolefin-based polymers such as polyethylene, polypropylene and copolymers of ethylene and propylene, polyester polymers, poly ( vinyl chloride), polymers based on polystyrene, acrylic polymers such as poly (methyl methacrylate) and its copolymers, polycarbonate polymers, polyurethanes, poly (isobutylenes), polytetrahydrofurans, polyanilines, acrylonitrile-butadiene-styrene copolymers (ABS polymers), polyamides such as nylon, polyimides, diene polymers such as polyisoprene (PI) and polybutadiene (PB) polysiloxanes such as polydimethylsiloxane (PDMS), polysulfones, polyimines, poly (acetic anhydrides), polyureas, polysulfides, polyphosphazenes, poly (ketones), polyphenylenes, polyhalo-olefins, and copolymers and / or or the mixtures of these polymers, preferably the polymer chain is chosen from poly (ethylene oxides), poly (propylene oxides), copolymers of poly (ethylene oxides), copolymers of poly (oxides of propylene), poly (isobutylenes), polydimethylsiloxane (PDMS), diene polymers such as polyisoprene (PI), polybutadiene (PB), styrene-butadiene copolymers (SBR), copolymers of styrene-isoprene (SIR), and ethylene-propylene-diene monomer (EPDM) copolymers, polyolefin-based polymers such as butene-ethylene copolymers (EBR), and mixtures of these polymers, and more preferably, the polymer chain is chosen from poly (ethylene oxides), poly (isobutylenes), and mixtures of these polymers. 3. Method according to claim 1 or 2, characterized in that the cyclodextrins are chosen from cyclodextrins with unmodified hydroxyl groups, cyclodextrins with partially or completely silylated hydroxyl groups and cyclodextrins with partially substituted hydroxyl groups by means of groups other than silyles. 4. Method according to any one of the preceding claims, characterized in that the cyclodextrins are chosen from α-cyclodextrins, β-cyclodextrins, γ-cyclodextrins, δ-cyclodextrins, and ε-cyclodextrins, and preferably the cyclodextrins are chosen from α-cyclodextrins and γ-cyclodextrins. 5. Method according to any one of the preceding claims, characterized in that the heat treatment step a) is carried out at a temperature ranging from 100 ° C to 250 ° C. 6. Method according to any one of the preceding claims, characterized in that the heat treatment step a) is carried out at a temperature ranging from 140 ° C to 250 ° C. 7. Method according to any one of the preceding claims, characterized in that the solvent of the dissolution step b) is selected from water, ethanol, dimethylformamide (DMF), dimethylsulfoxide (DMSO) , and a mixture of these solvents. 8. Method according to any one of the preceding claims, characterized in that the concentration of the product obtained in the heat treatment step a) in the solvent of the dissolution stage b) is 0.1 g / L to 150 g / L, and preferably is from 0.1 g / L to 20 g / L. 9. Method according to any one of the preceding claims, characterized in that it further comprises, between step b) and step c), a sonication step, preferably by means of ultrasound, of the solution obtained in step b). 10. Method according to claim 9, characterized in that the sonication step has a duration ranging from 1 min to 24 h, preferably from 15 min to 24 h. 11. The method of claim 9 or 10, characterized in that the sonication step is carried out at room temperature. 12. Method according to any one of the preceding claims, characterized in that the elimination step c) is carried out by centrifugation or by filtration, and preferably is carried out by centrifugation. 13. Method according to any one of the preceding claims, characterized in that the elimination step c) is carried out at ambient temperature. 14. Method according to any one of the preceding claims, characterized in that the elimination step c) has a duration ranging from 1 min to several hours, preferably from 10 min to 1 hour. 15. Method according to any one of the preceding claims, characterized in that the elimination step is carried out by centrifugation, with a relative centrifugal force (RCF) of between 100 g and 300 000 g, preferably between 1000 g and 30,000 g. 16. Method according to any one of the preceding claims, characterized in that it further comprises a step of drying the solution obtained in the elimination step c), preferably under reduced pressure. 17. Method according to claim 16, characterized in that the drying step is carried out under reduced pressure and is carried out at a temperature ranging from 0 ° C to 70 ° C, preferably from 0 ° C to 50 ° C, and more preferably is carried out at room temperature.