Hydrophobic and oleophobic cellulose substrate formed by grafting of fluorine-containing compounds and method for its preparation

Description

[0001] The present invention relates to a cellulosic substrate made hydrophobic and oleophobic by grafting fluorine-free compounds, as well as its methods of obtaining.

[0002] The textile and clothing industry uses 25% of all chemicals manufactured worldwide and contributes significantly to environmental pollution, particularly through the ubiquitous water-repellent finishes in textiles, both for consumer products and technical applications.

[0003] The textile industry often refers to these chemicals as durable water repellents (DWR), but the market's advanced technology does more than just repel water. Since their introduction in the 1950s, per- and polyfluoroalkyl polymers (PFAS) have enabled the highest level of oil and water resistance.

[0004] Water-repellent properties are essential for protection against harmful liquids, for example in medical textiles and protective clothing in the oil and gas industry; they are also vital for the health, safety, and comfort of outdoor sports enthusiasts in inclement weather or extreme environmental conditions. End-user requirements vary depending on the specific risks encountered and the environment of use. Water repellency in outdoor clothing is most often associated with rainwear, providing protection against rain and the external environment, resisting rain penetration while allowing the body to regulate its temperature; clothing with insufficient water-repellent properties increases the risk of hypothermia.In the field of medical textiles, the exposure and transfer of blood and bodily fluids between patients and medical personnel during emergency care or in hospitals is a major concern, with the risk of transferring bacteria and viruses. Blood and bodily fluid repellency is essential for occupational protection, and a repellent finish is necessary to achieve sufficient barrier properties; a high level of repellency is currently provided by fluoropolymers.

[0005] The PFAS used for repellent textile modifications most often comprise non-fluorinated polymer backbones with polyfluoropolymer side chains that branch from the main chain in comb-like structures. The length and degree of fluorination, the chemical nature of the carbon backbone, and the flexibility of the spacer units (non-fluorinated segments) that link the side chains to the main chain influence the performance characteristics of these fluoropolymer side chains (SFPs). The most effective water repellents are based on long-side-chain perfluoroalkyl SFPs (L-SFPs). The high level of hydrophobicity and oleophobicity provided by SFPs is due to the generation of low surface energy fiber surfaces by the orientation and stacking of the terminal -CF3 groups within the side chains.

[0006] The dispersal of PFAS byproducts during the production, use, and end-of-life of textiles containing them is a serious concern. These PFAS derivatives can be production residues, substances released by tearing (e.g., abrasion), or compounds formed by degradation processes. The ultimate contaminants released by textiles containing L-SFP-based compounds are long-chain perfluoroalkyl carboxylic acids (PFCAs). These perfluoroalkyl acids (PFAAs) are notorious for their toxicity and extreme persistence in the environment and have been widely identified in wildlife and humans worldwide. Within the European Union (EU), perfluorooctanesulfonic acid (PFOS) is regulated at detectable levels of <1 µg / m² in textile fabrics.While limits for perfluorooctanoic acid (PFOA) are currently being discussed within the EU, Norway has already set its limit at 1 µg / m² in textile applications. The bioaccumulation of PFAAs in humans and the food chain, combined with their toxicity, is a major concern.

[0007] The main challenge is to eliminate long-chain PFAS while maintaining the required functionality in water-repellent textiles. Substitution with short-chain fluorinated polymers (S-SFPs) with shorter fully fluorinated chain lengths, such as C6 or C4 analogs, has occurred, but the persistence and toxicology of these short-chain analogs are also raising increasing concerns. The extreme persistence of short-chain PFAS means that the release of these compounds from textiles (and other sources) could become a global threat, given that not all future effects are currently known and their release into groundwater, for example, is difficult to reverse.

[0008] In this context, various new non-fluorinated solutions have been developed to make textile surfaces water-repellent. Permanent non-fluorinated water repellents are composed of or comprise different architectures, including linear polyurethanes, hyperbranched polymers, or nanoparticles. The functional motifs in terms of liquid repellency are generally either saturated alkyl chains or related to the chemistry of polydimethylsiloxane (PDMS).

[0009] Thus, some manufacturers have developed and are currently producing non-fluorinated, permanent water repellents that offer more environmentally friendly alternatives to the persistent chemistry of PFAS. However, these compounds generally exhibit low oleophobic properties. This lack of oleophobicity makes the ultimate application of these non-fluorinated compounds in textiles still uncertain.

[0010] Document DE 199 62 272 A1 appears to be the closest prior art. It describes the modification of substrates to give them properties such as hydrophilic or hydrophobic properties using molecules with a polyurethane structure that may be terminated by functional groups. The substrate may, for example, be cellulosic in nature.

[0011] The invention aims to make available non-fluorinated materials and their methods of obtaining them which avoid the aforementioned disadvantages.

[0012] Thus, one of the objectives of the invention is to provide hydrophobic non-fluorinated materials which also have sufficient oleophobic character for the desired applications.

[0013] Another objective of the invention is to enable robust treatment of cellulosic substrates by covalent bond formation, using a process that is easy to implement, simple, fast and inexpensive.

[0014] Yet another objective of the invention is to make available materials such as those described above, which are also soft to the touch.

[0015] Thus, according to a first aspect, the invention relates to a cellulosic substrate bearing on at least a part of its surface a plurality of groups of the following formula (I): in which: Y is chosen from O and NH, or is a single bond; i is chosen from 0 and 1; X represents a group of the following formula (II): j and k are independently chosen from 0 and 1; X a and X c are independently chosen from: the groups X a1 being linear, branched and / or cyclic diyl alkanes in C 1 -C 12, in particular the groups of formula -(CH 2 ) n - with n from 1 to 12, or linear and branched diyl alkenes in C 2 -C 12, the groups X a1 being in particular linear and branched diyl alkanes in C 1 -C 12; the groups of formula -X a1 -NH-X a1 -, where X a1 is at each occurrence independently as defined above, in particular the groups of formula -(CH 2 ) n -NH-(CH 2 ) m - with n and m being independently from 1 to 12; the formula groups -X a1 -NHC(=O)-NH-X a1 - or -X a1 -NHC(=O)-NH-X a1 -NHC(=O)-NH-X a1 -, where X a1 is at each occurrence independently as defined above, in particular the formula groups -(CH 2 ) n -NHC(=O)-NH-(CH 2 ) m - with n and m being independently from 1 to 12;X b is chosen from: linear, branched and / or cyclic C1-C12 diyl alkanes, in particular groups of formula -(CH2)n- with n from 1 to 12, branched C1-C12 triyl alkanes, linear and branched C2-C12 diyl alkenes, the X b groups being in particular linear and branched C1-C12 diyl or triyl alkanes; optionally bearing, in particular in terminal position(s), at least one -(O-CH2-CH2)p- or -(O-CH2-C(CH3)H)p- group, with p being an integer from 1 to 3; diyl arenes and diyl heteroarenes; X b being optionally substituted by a group A of the following formula (III): ; X c , Y, i, Z and R being such as defined above or below, Z is chosen from linear, branched and / or cyclic C1-C12 diyl alkanes and linear and branched C2-C12 diyl alkenes, Z being in particular a linear C2 alkane or diyl alkene, said group Z being optionally substituted by a -COOH or -COO- group; R is chosen from: the groups of formula -NR a R b , and the groups -N +< R a R b R c , in which Ra , R b and R c are independently chosen from H and linear and branched C1-C6 alkyls, optionally substituted by at least one -OH group, in particular in terminal position(s), and aliphatic polyols.

[0016] When formula groups (I) include an ionized group, such as for example a -COO-< group or a -N+< group R a R b R c, said ionized groups may be in contact with a counter-ion, as is well known to the person skilled in the art.

[0017] By ZR, we indicate that R substitutes Z, this substitution being in terminal position, or not, of Z.

[0018] Without wanting to restrict ourselves to any particular theory, the chain bearing the R group allows the cellulosic substrate to have hydrophobic properties, while the R group itself, surprisingly, allows this cellulosic substrate to have oleophobic properties.

[0019] According to a preferred embodiment, the substrate of the invention does not comprise fluorinated compounds, nor does it carry fluorinated chains, for example polyfluorinated or even perfluorinated chains.

[0020] According to a particular embodiment, the substrate of the invention as described above comprises a plurality of motifs of the following formula (1):

[0021] Thus, the substrate of the invention is likely to include, in addition to the motifs of formula (1), substituted or unsubstituted D-glucose type motifs, in particular unsubstituted ones.

[0022] According to a particular embodiment, X is one of the following formulas:

[0023] According to a particular embodiment, R is chosen from the groups of formula -NRaRb, in which Ra and Rb are independently chosen from H and linear and branched C1-C6 alkyls, optionally substituted by at least one -OH group, particularly in terminal position(s), R being in particular chosen from the groups of formula -NH2, -NRaH, Ra being more particularly a methyl or an ethyl group, or -NRaRb, in which Ra and Rb are independently chosen from H and linear and branched C1-C6 alkyls, optionally substituted by at least one -OH group, particularly in terminal position(s), Ra and Rb being in particular independently chosen from linear and branched C1-C6 alkyls, substituted by at least one -OH group, particularly in terminal position(s), -NRaRb being, for example, of the formula next:

[0024] According to a particular embodiment, R is chosen from the groups of formula -N+<RaRbH, in which Ra and Rb are independently chosen from H and linear and branched C1-C6 alkyls, optionally substituted by at least one -OH group, especially in terminal position(s), R being particularly chosen from the groups of formula -N+<H2, -N+<RaH, Ra being more particularly a methyl or an ethyl, or -N+<RaRb, in which Ra and Rb are independently chosen from H and linear and branched C1-C6 alkyls, optionally substituted by at least one -OH group, especially in terminal position(s), Ra and Rb being especially independently chosen from linear and branched C1-C6 alkyls substituted by at least one -OH group, especially in terminal position(s), -N+<RaRb being for example of the following formula:

[0025] Aliphatic polyols include polyols comprising at least two -OH groups, in particular polyols comprising at least three -OH groups, for example polyols comprising three -OH groups.

[0026] According to a particular embodiment, R is chosen from aliphatic polyols, in particular from linear and branched C1-C6 alkyls, substituted by at least two -OH groups, especially in terminal position(s), R being for example of the following formula:

[0027] According to a particular embodiment, the group Y-(Z) i -R is of one of the following formulas: -NH-Z-NR a R b , in which R a and R b are independently selected from H and linear and branched C 1 -C 6 alkyls, optionally substituted by at least one -OH group, especially in terminal position(s), R being in particular selected from groups of formula -NH 2 , -NR a H, R a being more particularly a methyl or an ethyl, or -NR a R b , in which R a and R b are independently selected from H and linear and branched C 1 -C 6 alkyls, optionally substituted by at least one -OH group, especially in terminal position(s);-OZ-NR a R b , in which R a and R b are independently chosen from H and linear and branched C 1 -C 6 alkyls substituted by at least one -OH group, especially in terminal position(s), R being in particular -NR a R b , in which R a and R b are independently chosen from H and linear and branched C 1 -C 6 alkyls substituted by at least one -OH group, especially in terminal position(s), R a and R b being in particular independently chosen from linear and branched C 1 -C 6 alkyls substituted by at least one -OH group, especially in terminal position(s), -NR a R b being for example of the following formula: ; -NH-ZN +< R a R b H, in which R a and R b are independently chosen from H and linear and branched C 1 -C 6 alkyls, optionally substituted by at least one -OH group, especially in terminal position(s), R being in particular chosen from groups of formula -N +< H 2 , -N +< R a H, R a being more particularly a methyl or an ethyl, or - N +< R a R b , in which R a and R b are independently chosen from H and linear and branched C 1 -C 6 alkyls, optionally substituted by at least one -OH group, especially in terminal position(s);-OZN +< R a R b H, in which R a and R b are independently chosen from H and linear and branched C 1 -C 6 alkyls, substituted by at least one -OH group, especially in terminal position(s), R being in particular -N +< R a R b, in which R a and R b are independently chosen from H and linear and branched C 1 -C 6 alkyls, substituted by at least one -OH group, especially in terminal position(s), R a and R b being in particular independently chosen from linear and branched C 1 -C 6 alkyls, substituted by at least one -OH group, especially in terminal position(s), -N +< R a R b being for example of the following formula: ; -NH-R, in which R is chosen from aliphatic polyols, in particular from linear and branched C1-C6 alkyls, substituted by at least two -OH groups, especially in terminal position(s), R being for example of the following formula:

[0028] According to a particular embodiment, X b is chosen from the following groups: A and p being such as defined previously.

[0029] According to a particular embodiment, the formula groups (I) are chosen from the following formula groups:

[0030] According to a particular embodiment, the substrate of the invention as described above is chosen from among the tissues.

[0031] According to a particular embodiment, the substrate of the invention as described above is made of or comprises a material selected from cottons, hemps, linens, Tencel, viscose.

[0032] Viscoses containing free -OH groups can, for example, be obtained by partial acid hydrolysis of viscoses known to those skilled in the art, such as commercial viscoses. Acid hydrolysis is also well known to those skilled in the art, particularly for the preparation of cellophane from viscose.

[0033] The said cellulosic substrate may also include, for example in addition to cotton, other materials such as polyurethanes, for example at a level of about 4% by mass, and / or optical brighteners (OBA).

[0034] According to a particular embodiment, the substrate of the invention as described above is made of or comprises a material selected from woven cottons, woven hemps, woven linens, woven Tencel, woven viscose.

[0035] According to a particular embodiment, the substrate of the invention as described above is such that: the contact angle of a water droplet on the surface of said substrate is greater than or equal to 80°, in particular greater than or equal to 90, 100, 110 or 120°, in particular under a relative humidity (RH) of 20 and / or 80%, and / or the contact angle of an oil droplet, for example dodecane, on the surface of said substrate is greater than or equal to 40°, in particular greater than or equal to 50, 60 or 70°, in particular under a relative humidity (RH) of 20 and / or 80%.

[0036] This contact angle can be measured using techniques well known to those skilled in the art, for example by goniometry. This technique typically involves depositing a small liquid drop, for example with a volume of 1 to 10 µl, onto the surface and measuring the angle formed between the tangent to the drop at the point of contact and the surface of the cellulosic substrate.

[0037] This contact angle can be measured on a sufficiently large sample of cellulosic substrate to be stretched during the measurement, for example on a wetting angle measuring plate. For this purpose, the samples typically weigh between 0.8 and 1.2 g before drying.

[0038] Wetting angle measurements can for example be carried out on a KRÜSS DROP Shape Analyser (DSA100).

[0039] The cellulosic substrates of the present invention can be prepared by a number of methods well known to those skilled in the art, including, but not limited to, those described below, or by modifications of these methods applying standard techniques known to those skilled in the art of organic synthesis. Appropriate modifications and substitutions will be readily apparent and well known or can be easily obtained from the scientific literature by those skilled in the art. In particular, such methods can be found in R.C. Larock, Comprehensive Organic Transformations, Wiley-VCH Publishers, 1999.

[0040] All the processes disclosed in association with the present invention can be carried out at any scale, including milligram, gram, multigram, kilogram, multikilogram or commercial industrial scale.

[0041] It will be understood that the compounds of the present invention may contain one or more asymmetrically substituted carbon atoms and may be isolated in optically active or racemic forms. Thus, all chiral, diastereomeric, racemic, and isomeric forms of a structure are included, unless the specific stereochemistry or isomeric form is specifically indicated. The method of preparing and isolating these optically active forms is well known to those skilled in the art. For example, mixtures of stereoisomers may be separated by standard techniques including, but not limited to, racemic resolution, conventional, reversed-phase, and chiral chromatography, preferential salt formation, recrystallization, and others, or by chiral synthesis, either from chiral starting materials or by targeted synthesis of the corresponding chiral centers.

[0042] The compounds of the present invention can be prepared by a variety of synthetic routes. The reagents and starting materials are commercially available or readily synthesized by techniques well known to those skilled in the art. All substituents, unless otherwise specified, are as defined above.

[0043] More particularly, the cellulosic substrates of the invention, bearing a plurality of formula groups (I), are likely to include -NH-C(=O)-NH- (urea), -NH-C(=O)-O- or -OC(=O)-NH- (urethane), and / or -NH-C(=O)- or -C(=O)-NH- (amide) groups.

[0044] The -NH-C(=O)-NH- group can be formed by any method well known to those skilled in the art, in particular by contacting a compound bearing an -NH₂ group (primary amine) with a compound bearing an -N=C=O group (isocyanate). This reaction can be carried out in an anhydrous solvent, especially an anhydrous aprotic solvent, for example dimethyl sulfoxide (DMSO), tetrahydrofuran (THF), 1,4-dioxane, acetone, and / or in supercritical CO₂. This reaction can be carried out at a temperature from 35°C to 150°C, in particular at about 150°C, and / or for a duration from 30 minutes to 2 hours, in particular for about 1.5 hours.

[0045] The -NH-C(=O)-O- or -OC(=O)-NH group can be formed by any method well known to those skilled in the art, in particular by contacting a compound bearing an -OH group (primary alcohol) with a compound bearing an -N=C=O group (isocyanate), especially in the presence of a catalyst, notably triethylamine, 1,4-diazabicyclo[2,2,2]octane (DABCO), 1,5-diazabicyclo[4,3,0]non-5-ene (DBN), dibutyltin dilaurate (DBTDL), 1,8-diazabicyclo[5,4,0]undec-7-ene (DBU), 3,4-dihydro-2H-pyrimido[2,1-b]benzothiazole (DHPB), diisopropylethylamine (DIPEA), 4-dimethylaminopyridine (DMAP), 1,8-bis(dimethylamino)naphthalene (DMAN), for example triethylamine. This reaction can in particular be carried out in an anhydrous solvent, in particular an anhydrous aprotic solvent, for example dimethyl sulfoxide (DMSO), and / or in supercritical CO2.This reaction can be carried out at a temperature of 70°C to 150°C, in particular at about 150°C, and / or for a duration of 30 minutes to 2 hours, in particular for about 1.5 hours.

[0046] The NH-C(=O)- or -C(=O)-NH- group can be formed by any method well known to those skilled in the art, in particular by contacting a compound bearing a -COOH group (carboxylic acid) with a compound bearing an -N=C=O group (isocyanate), particularly in the presence of a catalyst, notably chosen from triethylamine, 1,4-diazabicyclo[2,2,2]octane (DABCO), 1,5-diazabicyclo[4.3.0]non-5-ene (DBN), dibutyltin dilaurate (DBTDL), 1,8-diazabicyclo[5,4,0]undec-7-ene (DBU), 3,4-dihydro-2H-pyrimido[2,1-b]benzothiazole (DHPB), diisopropylethylamine (DIPEA), 4-dimethylaminopyridine (DMAP), 1,8-bis(dimethylamino)naphthalene (DMAN), for example triethylamine. This reaction can in particular be carried out in an anhydrous solvent, especially an anhydrous aprotic solvent, for example dimethyl sulfoxide (DMSO), and / or in supercritical CO2.This reaction can be carried out at a temperature of 70°C to 160°C, in particular at about 150°C, and / or for a duration of 30 minutes to 2 hours, in particular for about 1.5 hours.

[0047] According to another aspect, the invention also relates to a method for preparing a cellulosic substrate as defined above, comprising the following step: (i) Bringing at least a part of the surface of a cellulosic substrate into contact with a compound (A) of the following formula: in which X, Y, i, Z and R are as defined above; or the following steps: (i') bringing at least a part of the surface of a cellulosic substrate into contact with a compound (B) of the following formula: in which X is as defined previously, to obtain a cellulosic substrate bearing on at least part of its surface a plurality of groups of the following formula (C): in which W, i and X are as defined previously, (ii') the contacting of a substrate as obtained in the previous step (i') with a compound of the following formula (D): in which Z and R are as defined previously, and in which Y' is: an -NH2 group when j = 1 and Y is -NH-; an -OH group when j = 1 and Y is -O-; a -COOH group when Y is a single bond; or, when Y is NH, and R is -NH2, the following steps: (i) bringing at least a part of the surface of a cellulosic substrate into contact with a compound (B) of the following formula: in which X is as defined previously, then contact with water, to obtain a cellulosic substrate bearing on at least part of its surface a plurality of groups of the following formula (C): in which W, i and X are as defined previously, (ii) the contacting of a substrate as obtained in the previous step (i') with a compound of the following formula (D): in which Z is as defined previously, then a contact with water.

[0048] When water is used, residual traces of water can be removed, for example by washing with a solvent as described below.

[0049] When R has the formula -N +< R a R b R c , compounds bearing this group R can be obtained from the corresponding compounds bearing a group -NR a R b , using techniques well known to those skilled in the art.

[0050] When group X includes one or more urea groups, said group X can be constructed sequentially in steps analogous to steps (i") and (ii") as described above.

[0051] The steps defined above are in particular carried out in an anhydrous solvent, in particular an anhydrous aprotic solvent, for example dimethyl sulfoxide (DMSO), tetrahydrofuran (THF), or acetone.

[0052] According to a particular embodiment, the steps defined above are carried out in supercritical CO2 (sCO2).

[0053] According to another particular embodiment, the steps defined above are carried out in an anhydrous aprotic solvent, for example dimethyl sulfoxide (DMSO), tetrahydrofuran (THF), or acetone, with supercritical CO2 (sCO2) as a co-solvent.

[0054] The use of supercritical CO2 generally requires working in a pressurized autoclave, which protects operators from isocyanates.

[0055] The isocyanates described here can also be used via blocked isocyanate functions, such as for example defined in application FR 3 095 207.

[0056] Step (i) defined above may, if necessary, be preceded by a step in which residual water is removed from the cellulosic substrate. This removal may be carried out by any technique well known to those skilled in the art.

[0057] The steps defined above are in particular carried out at a temperature of 35°C to 160°C, in particular at about 150°C, and / or for a duration of 30 minutes to 2 hours, in particular for about 1.5 hours.

[0058] When sCO2 is used, the reactions are carried out in an autoclave, for example under a pressure of approximately 250 bar. Definitions

[0059] As understood here, ranges of values ​​in the form of "xy," "from x to y," or "between x and y" include the bounds x and y, the integers between these bounds, and all other real numbers between these bounds. For example, "1-5," "from 1 to 5," or "between 1 and 5" denotes the integers 1, 2, 3, 4, and 5, as well as all other real numbers between 1 and 5. Preferred embodiments include each individual integer within the range of values, as well as any subcombination of these integers and any set of real numbers between these integers. As an example, preferred values ​​for "1-5" may include the integers 1, 2, 3, 4, 5, 1-2, 1-3, 1-4, 1-5, 2-3, 2-4, 2-5, etc.

[0060] As used in this description, the term "approximately" refers to a range of values ​​within ±10% of a specific value. For example, the expression "approximately 20" includes values ​​within 20 ± 10%, that is, values ​​from 18 to 22.

[0061] As used here, the term "alkyl" refers to a linear or branched alkyl group, particularly a linear one, having the number of carbon atoms indicated before the term, specifically 1 to 4 carbon atoms, such as methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl, tert-butyl, etc. Thus, an expression such as "C1-C3 alkyl" refers to an alkyl radical containing 1 to 3 carbon atoms.

[0062] The same applies to the term "alkane".

[0063] By "diyl" we mean in particular a residue linked to two groups by a single bond between the residue and each of these two groups.

[0064] As used here, the term "arene" refers to a mono- or bicyclic, substituted or unsubstituted, aromatic hydrocarbon cyclic system with 6 to 10 carbon atoms in the ring. Examples include benzene and naphthalene. Preferred arenes include unsubstituted and substituted benzene and naphthalene. Also included in the definition of "arene" are condensed cyclic systems, including, for example, cyclic systems in which an aromatic ring is condensed to a cycloalkyl ring. Examples of such condensed cyclic systems include, for example, indane, indene, and tetrahydronaphthalene.

[0065] As used here, the term "heteroarene" refers to a cyclic aromatic system containing 5 to 10 carbon atoms in which one or more ring carbon atoms are replaced by at least one heteroatom such as -O-, -N- or -S-, in particular -N- and / or -O-. Examples of heteroarenes include pyrrole, furan, thiophene, pyrazole, imidazole, thiazole, isothiazole, isoxazole, oxazole, oxathiol, oxadiazole, triazole, oxatriazole, furazane, tetrazole, pyridine, pyrazine, pyrimidine, pyridazine, triazine, indole, isoindole, indazole, benzofuran, isobenzofuran, purine, quinazoline, quinoline, isoquinoline, benzoimidazole, benzothiazole, benzothiophene, thianaphthene, benzoxazole, benzisoxazole, cinnoline, phthalazine, naphthyridine and quinoxaline. Included in the definition of "heteroarene" are condensed cyclic systems, including, for example, cyclic systems in which an aromatic ring is condensed to a heterocycloalkyl ring.Examples of such fused cyclic systems include, for example, phthalamide, phthalic anhydride, indoline, isoindoline, tetrahydroisoquinoline, chromane, isochromane, chromene and isochromene. EXAMPLES General operating protocols

[0066] The experiments were carried out on cotton containing 4 to 5% by mass of polyurethanes (elastane) and an optical brightener (OBA).

[0067] The samples weigh between 0.8 and 1.2g before drying. This mass corresponds to a fabric surface area allowing the sample to be stretched on the wetting angle measurement plate.

[0068] The samples were pre-treated in a supercritical CO₂ (sCO₂) reactor using an aprotic solvent (e.g., acetone, THF, or DMSO) as a co-solvent. The drying medium is, for example, 10 ml of aprotic solvent per 1 liter of sCO₂. Typically, 20 cotton samples are treated. The treatment lasts 1.5 hours at 120°C and 250 bar. The treatment is completed by a pass of pure sCO₂ (2 to 4 liters). The samples are stored in the reactor under a CO₂ gaseous atmosphere.

[0069] This treatment can also be carried out by soaking the samples for 5 hours in DMSO at 120-150°C. In this case, the substrates are dried in a ventilated oven and stored under argon.

[0070] These preliminary treatments allow for the extraction of OBA and other finishing products. These treatments also allow for the dehydration of the cotton.

[0071] After processing according to the invention, all samples were extracted using a Soxhlet extractor to remove unbound compounds. This extraction was carried out in acetone for 4 hours (corresponding to a 5-liter acetone infusion). The samples were then placed in an oven at 110°C for 12 hours before being conditioned at the relative humidities (RH) chosen prior to wettability measurement. Contact angle (wetting) measurements were performed using a KRÜSS DROP Shape Analyzer (DSA100) on samples (5 samples for water and 5 for dodecane) previously cured in an oven at 100°C. Example 1 : Preparation of intermediate functionalized cellulosic substrates

[0072] In a 1-liter sCO2 reactor containing 10 to 15 cotton samples, 5 g of hexamethyldiisocyanate are introduced into 10 g of DMSO containing 1 g of DABCO: (1,4-Diazabicyclo[2.2.2]octane anhydrous). Then, 900 mL of liquid CO2 is added. The reactor is brought to a supercritical state by heating it to 150°C at a pressure of 250 bar. The treatment lasts 1.5 hours. Then, 10 mL of DI water is introduced into the pressurized reactor via a high-pressure pump. Any remaining isocyanate groups or unreacted HDMI are immediately converted to primary amines. Several volumes of the supercritical sCO2 reactor (typically 5 volumes) are then passed through it. The DABCO, which is soluble in sCO2, and the corresponding primary amines, corresponding to HDMI, are recovered in the reactor separators. which did not react. The cotton substrates are then covered with anhydrous primary amine.

[0073] In all of the above and following, anhydrous DMSO can be used instead of sCO2. Example 2:

[0074] Starting with the cotton substrates coated with anhydrous primary amine, as obtained in Example 1, the initial treatment is repeated: In a 1-liter sCO2 reactor containing 10 to 15 cotton samples bearing pendant primary amines, 5 g of hexamethyldiisocyanate is introduced into 10 g of DMSO. The formation of the urea group does not require the use of a catalyst. Then, 900 mL of liquid CO2 is introduced. The reaction is brought to a supercritical state by heating the reactor to 150°C at a pressure of 250 bar. The treatment lasts 1.5 hours. Then, 10 mL of DI water is introduced into the pressurized reactor via a high-pressure pump. Any unreacted pendant isocyanate or HDMI groups are immediately converted into primary amines. Several volumes of sCO2 are then passed through the reactor (typically 5 volumes).The primary amines corresponding to the HDMI that did not react on the cotton and which was transformed into diamine are recovered in the reactor separators.

[0075] The reactor is opened, the samples are then soaked for 10 minutes in 100 ml of a 0.1 M HCl solution, rinsed with DI water, and then dried for 12 hours at 130°C in a ventilated oven. These samples correspond to the reference 1 from the table below. Example 3 :

[0076] We repeat example 2, 2 times to form the species corresponding to reference 1b in the table below. Example 4 : Witness outside the invention

[0077] In a 1-liter sCO2 reactor containing 10 to 15 cotton samples bearing pendant grafted primary amines, 5 g of hexamethyldiisocyanate are introduced into 10 g of DMSO. Then, 900 ml of liquid CO2 is added. The reaction is brought to a supercritical state by heating the reactor to 150°C at a pressure of 250 bar. This treatment lasts 1.5 hours. Next, 5 g of octadecylamine are introduced into 5 g of DMSO using a high-pressure pump. The reaction is allowed to proceed for 1.5 hours at 250 bar and 150°C. Several volumes of the sCO2 reactor (typically 5 volumes) are then passed through, again at 250 bar and 150°C, to remove the ungrafted products.

[0078] These samples correspond to the reference 2 of the painting. Example 5:

[0079] In a 1-liter sCO2 reactor containing 10 to 15 cotton samples bearing pendant primary amines, 5 g of hexamethyldiisocyanate are introduced into 10 g of DMSO. Then, 900 mL of liquid CO2 is added. The reaction is brought to a supercritical state by heating the reactor to 150°C at a pressure of 250 bar. This treatment lasts 1.5 hours. Next, 3 g of 1,3-Pentanediamine in 5 g of DMSO are introduced into the pressurized reactor via a high-pressure pump. The reaction is allowed to proceed for 1.5 hours at 250 bar and 150°C. Several reactor volumes of sCO2 (typically 5 volumes) are then passed through the reactor.

[0080] The reactor is opened, the samples are then soaked for 10 minutes in 100 ml of a 0.1 M HCl solution, rinsed with DI water, and then dried for 12 hours at 130°C in a ventilated oven. These samples correspond to the reference 3 of the painting. Example 6:

[0081] In a 1-liter sCO2 reactor containing 10 to 15 cotton samples bearing pendant grafted primary amines, 5 g of hexamethyldiisocyanate are introduced into 10 g of DMSO. Then, 900 mL of liquid CO2 is added. The reaction is brought to a supercritical state by heating the reactor to 150°C at a pressure of 250 bar. The treatment lasts 1.5 hours. Next, 5 g of 2-Amino-2-(hydroxymethyl)-1,3-propanediol are introduced into 5 g of DMSO using a high-pressure pump. The reaction is allowed to proceed for 1.5 hours at 250 bar and 150°C. Several volumes of the sCO2 reactor (typically 5 volumes) are then passed through, again at 250 bar and 150°C, to remove the ungrafted products.

[0082] These samples correspond to the reference 4 of the painting. Example 7:

[0083] In a 1-liter sCO2 reactor containing 10 to 15 cotton samples bearing pendant grafted primary amines, 5 g of hexamethyldiisocyanate are introduced into 10 g of DMSO. Then, 900 mL of liquid CO2 is added. The reaction is brought to a supercritical state by heating the reactor to 150°C at a pressure of 250 bar. The treatment lasts 1.5 hours. Next, 5 g of 2,2-Bis(hydroxymethyl)-2,2'2'-nitrilotriethanol are introduced into 5 g of DMSO using a high-pressure pump. The reaction is allowed to proceed for 1.5 hours at 250 bar and 150°C. Several volumes of the sCO2 reactor (typically 5 volumes) are then passed through, again at 250 bar and 150°C, to remove the ungrafted products.

[0084] These samples correspond to the reference 5 of the painting. Example 8: Results

[0085] The results recorded in the table below show that the treated substrates of the invention are hydrophobic while having a marked oleophobic character. [Chem. 21]

[0086] Reference Structure Mooring angle 20% RH Wetting Angle 80%RH 1 θH2O 110° θH2O 60° θDode 30° θDode 70° 2 (reference outside the invention) θH2O 140° θH2O 140° θDode<30' θDode<30° 1 bis θH2O 110° θH2O 60° θDode 70° θDode 50° 3 θH2O 115° θH2O 90° θDode<60° θDode 60-80° 4 θH2O 80° θH2O 80° θDode 40° θDode 40° 5 θH2O 80° θH2O 80° θDode 70° θDode 70°

Claims

1. A cellulosic substrate bearing, on at least a portion of its surface, a plurality of groups of the following formula (I): wherein: Y is selected from O and NH, or is a single bond; i is selected from 0 and 1; X represents a group of the following formula (II): j and k are independently selected from 0 and 1; Xa and Xc are independently selected from: - the groups Xa1 being linear, branched, and / or cyclic C1-C12 alkanediyl groups, in particular groups of formula -(CH2)n- with n from 1 to 12, or linear and branched C2-C12 alkenediyl groups, the groups Xa1 being in particular linear and branched C1-C12 alkanediyl groups; - groups of formula -Xa1-NH-Xa1-, where Xa1 is, at each occurrence, independently as defined above, in particular groups of formula -(CH2)n-NH-(CH2)m- with n and m independently ranging from 1 to 12; - groups of the formula -Xa1-NHC(=O)-NH-Xa1- or -Xa1-NHC(=O)-NH-Xa1-NHC(=O)-NH-Xa1-, where Xa1 is, at each occurrence, independently as defined above, in particular groups of the formula -(CH2)n-NHC(=O)-NH-(CH2)m- with n and m independently ranging from 1 to 12; Xb is selected from: - linear, branched, and / or cyclic C1-C12 alkanediyl groups, in particular groups of the formula -(CH2)n- with n ranging from 1 to 12, branched C1-C12 alkanetriyl group, linear and branched C2-C12 alkenediyl groups, the groups Xb being, in particular, linear and branched C1-C12 alkanediyl or alkanetriyl groups; optionally bearing, in particular at terminal position(s), at least one group -(O-CH2-CH2)p- or -(O-CH2-C(CH3)H)p-, where p is an integer from 1 to 3; - arylene and heteroarylene groups ; Xb is optionally substituted by a group A of the following formula (III): Xc, Y, i, Z, and R are as defined above or below, Z is selected from linear, branched, and / or cyclic C1-C12 alkanediyl groups and linear and branched C2-C12 alkenediyl groups, Z being, in particular, a linear C2 alkanediyl or alkenediyl group, said group Z being optionally substituted by a -COOH or -COO- group; R is selected from: - groups of the formula -NRaRb, and groups -N+RaRbRc, wherein Ra, Rb, and Rc are independently selected from H and linear or branched C1 -C6 alkyl groups, optionally substituted by at least one -OH group, particularly at terminal position(s), and - aliphatic polyols.

2. The cellulosic substrate according to claim 1, comprising a plurality of units of the following formula (1):

3. The cellulosic substrate according to claim 1, wherein R is selected from: - groups of the formula -NRaRb, wherein Ra and Rb are independently selected from H and linear and branched C1-C6 alkyl groups, optionally substituted by at least one - OH group, particularly at terminal position(s), R being in particular selected from groups of the formula -NH2, -NRaH, Ra being more particularly methyl or ethyl, or - NRaRb, wherein Ra and Rb are independently selected from H and linear and branched C1-C6 alkyl groups, optionally substituted by at least one -OH group, particularly at terminal position(s), Ra and Rb being in particular independently selected from linear and branched C1-C6 alkyl groups, substituted by at least one -OH group, in particular at terminal position(s), -NRaRb being, for example, of the following formula: - groups of the formula -N+RaRbH, wherein Ra and Rb are independently selected from H and linear and branched C1-C6 alkyl groups, optionally substituted by at least one -OH group, particularly at the terminal position(s), R being in particular selected from groups of the formula -N+H2, -N+RaH, Ra being more particularly a methyl or an ethyl group, or -N+RaRb, wherein R and Rb are independently selected from H and linear and branched C1-C6 alkyl groups, optionally substituted by at least one -OH group, particularly at terminal position(s), Ra and Rb being in particular independently selected from linear and branched C1-C6 alkyl groups, substituted by at least one -OH group, in particular at terminal position(s), -N+RaRb being, for example, of the following formula: - aliphatic polyols, in particular linear and branched C1-C6 alkyl groups, substituted by at least two -OH groups, particularly at terminal positions, R being, for example, of the following formula:

4. The cellulosic substrate according to any one of the preceding claims, wherein Xb is selected from the following groups: A and p are as defined in claim 1.

5. The cellulosic substrate according to any one of the preceding claims, wherein the groups of formula (I) are selected from the groups of the following formula:

6. The cellulosic substrate according to any one of the preceding claims, which is selected from fabrics.

7. The cellulosic substrate according to any one of the preceding claims, which consists of or comprises a material selected from cottons, hemps, Tencel, linens, and viscoses.

8. The cellulosic substrate according to any of the preceding claims, comprising or consisting of a material selected from woven cottons, woven hemp, woven Tencel, woven linens, and woven viscose.

9. The cellulosic substrate according to any one of the preceding claims, wherein: - the contact angle of a water droplet on the surface of said substrate is greater than or equal to 80°, notably greater than or equal to 90, 100, 110, or 120°, particularly at a relative humidity (RH) of 20% and / or 80%, and / or - the contact angle of a drop of oil, for example dodecane, on the surface of said substrate is greater than or equal to 40°, in particular greater than or equal to 50, 60, or 70°, especially at a relative humidity (RH) of 20% and / or 80%.

10. A method for preparing a cellulosic substrate according to any of the preceding claims, comprising the following step: (i) Bringing at least a portion of the surface of a cellulosic substrate into contact with a compound (A) of the following formula: wherein X, Y, i, Z, and R are as defined in claim 1. or the following steps: (i') contacting at least a portion of the surface of a cellulosic substrate with a compound (B) of the following formula: [Chem. 32]         O=C=N-X-N=C=O     (B), wherein X is as defined in claim 1, to obtain a cellulosic substrate bearing, on at least a portion of its surface, a plurality of groups of the following formula (C): wherein W, i, and X are as defined in claim 1, (ii') bringing a substrate as obtained in the preceding step (i') into contact with a compound of the following formula (D): wherein Z and R are as defined in claim 1, and wherein Y' is: - a -NH2 group when j = 1 and Y is -NH-; - a -OH group when j = 1 and Y is -O-; - a -COOH group when Y is a single bond, or, when Y is NH, and R is -NH2, the following steps: (i") bringing at least a portion of the surface of a cellulosic substrate into contact with a compound (B) of following formula: [Chem. 35]         O=C=N-X-N=C=O     (B), wherein X is as defined above, followed by contact with water, to obtain a cellulosic substrate having, on at least part of its surface, a plurality of groups of the following formula (C): wherein W, i and X are as previously defined, (ii") bringing a substrate as obtained in the preceding step (i') into contact with a compound of the following formula (D): [Chem. 37]         O=C=N-Z-N=C=O     (D), wherein Z is as defined above, followed by contact with water.