FR3016367A1 - LIEGE / BINDER ASSOCIATION BASED ON POLYHYDROXYURETHANE AND PROCESS FOR PREPARING THE SAME - Google Patents

Abstract

The invention relates to a composition comprising cork or a cork-based material and a binder comprising at least one polyhydroxyurethane prepared from non-highly toxic raw materials, preferably from biomass. In particular, the polyhydroxyurethane binder is synthesized from at least one compound (A) having two or more cyclocarbonate groups and at least one compound (B) having two or more amine groups. The invention also relates to the process for preparing said composition.

Description

The present invention relates to a composition comprising cork or a cork-based material and a binder which comprises at least one particular polyhydroxyurethane, its method of preparation, a method for preparing the cork or a binder based on polyhydroxyurethane and a method for preparing the same. making a stopper and using a polyhydroxyurethane as an adhesive for cork or a cork-based material.

Cork is a natural, impervious and light material, which comes from the bark of some species of oaks, such as cork oaks, which are typically found in the countries around the Mediterranean, Europe and North Africa. Cork is particularly used in the manufacture of corks, which serve to plug containers such as bottles containing liquids for food, especially wine. Cork is an elastic material, resilient, compressible and impermeable to liquids, having at the same time a gas permeability sufficient to allow an exchange necessary for the maturation of the bottled product, and having a high coefficient of friction. Much research has been conducted to try to develop compositions whose properties are similar to those of natural cork and which can replace it especially for the manufacture of corks, for example corks for closing wine bottles. In fact, cork harvesting is limited to a few areas of the world in which cork oak cultivation is profitable, and the production of natural cork barely balances needs. This research led to the manufacture of agglomerated cork stoppers consisting of cork particles and a binder or glue which ensures the cohesion of the stopper.

It has also been tried to manufacture fully synthetic plugs, especially based on polyethylene or other plastics. However, all caps, their known manufacturing processes and their composition have drawbacks and do not use only natural raw materials. In addition, polyurethane glues used to ensure the cohesion of the cap, have the disadvantage of being manufactured with monomers of the family of isocyanates whose regulations for food contact becomes increasingly restrictive. Indeed, the polyurethanes are usually formed from the reaction between a diisocyanate and a compound having two functions with a mobile hydrogen, mainly hydroxyl groups, for example a diol. A disadvantage of these polyurethanes is their mode of synthesis which involves the use of monomers comprising several highly reactive isocyanate functions which make them very dangerous or even toxic monomers. The production of polyurethanes therefore presents numerous chemical risks and is dangerous for the operators. Many research studies have been carried out to implement less dangerous formulations. There is therefore a need to produce a composition obtained from non-highly toxic natural raw materials, having both good mechanical and organoleptic properties. For the purposes of the present invention, the term "non-highly toxic raw materials" means raw materials which are not classifiable carcinogenic-mutagenic-repellent (or CMR) molecules, classes 1A, 1B and 2. The invention aims to satisfy this need by proposing a new composition comprising cork or a cork-based material, and a binder which comprises one or more polyhydroxyurethanes as defined below, the binder being partially or totally bio sourced.

For the purposes of the present invention, the term "biosourced" is intended to mean a compound derived from biomass which has or has not undergone chemical treatment, and which is not classified as CMR, classes 1A, 1B and 2. As examples of biomass, there may be mentioned extracts of plants, trees, vines, fruits, vegetables or algae. The polyhydroxyurethanes result from the reaction between a compound having two or more amine functions and a compound having two or more cyclic carbonate functions with 5, 6 or 7 members, and do not use isocyanate compounds. These are sometimes also called NIPU ("Non Isocyanate Polyurethanes" or polyurethanes without isocyanate) due to the formation of a hydroxyl group (-OH) at the p-position of the urethane function during the reaction. The composition according to the invention is especially intended for the manufacture of corks, in particular for still, effervescent or spirits wine bottles or aqueous solutions such as fruit juices, or oils. Corks, thus produced and containing at least a portion of agglomerated cork based on a binder, retain the advantages of natural cork, with physical characteristics that are close to or even greater and with an external appearance similar to that of natural cork. In addition, these plugs do not have the drawbacks of known synthetic plugs, especially for their lack of elasticity, their low gas tightness over time and their external appearance different from natural cork. Thus, the composition can be applied to all the stoppers with at least one agglomerated part as is the case for champagne corks or sparkling wines, corks with one or more washers at one or both ends (1+ 1, 2 + 2, 0 + 2 or any other possible combination). The composition may be obtained by molding process or by extrusion or by any thermal process for reacting the ingredients of the composition under the conditions of temperature, pressure and time adequate for the invention.

This composition according to the invention makes it possible to obtain a plug having both good mechanical, organoleptic and hydrophobicity properties. A first object of the present invention is therefore a composition comprising cork or a cork-based material and a binder which comprises one or more polyhydroxyurethanes resulting from the mixture of one or more compounds (A) comprising two or more groups cyclocarbonates with one or more compounds (B) having two or more amine groups.

Another object is a composition comprising cork or a cork material, one or more compounds (A) having two or more cyclocarbonate groups and one or more compounds (B) having two or more amine groups.

The invention further relates to a process for preparing said composition. Yet another object is a method of making stoppers using such a composition. The invention still has a cap that can be obtained by the manufacturing process. Other characteristics and advantages of the invention will emerge more clearly on reading the description and examples which follow. In what follows, and unless otherwise indicated, the boundaries of a domain of values are included in this field, especially in the expressions "between" and "from ... to". Moreover, the expression "at least one" used in the present description is equivalent to the expression "one or more".

According to the invention, the composition comprises cork or a cork-based material and a binder which comprises one or more polyhydroxyurethanes resulting from the mixture of one or more compounds (A) having two or more cyclocarbonate groups with one or more several compounds (B) having two or more amine groups. The cork or the cork-based material that can be used in the invention is in particular in the form of a flour, granules preferably having a particle size of 0.01 mm up to 8 mm, plates, washers cork from the casing of cork plates, preferably in the form of a flour. The particle size can be measured for example by the sieve method, at room temperature (20-25 ° C).

The cork or cork-based material is preferably present in an amount ranging from 1 to 95% by weight, more preferably from 10 to 90% by weight, and still more preferably from 50 to 85% by weight relative to the total weight of the cork. composition. The polyhydroxyurethanes (or PHU) used in the composition according to the invention are partially or completely biobased. They are prepared from biobased raw materials as specified above, namely raw materials from biomass and not classified CMR, classes 1A, 1B and 2.

In particular, they are synthesized from at least one compound (A) comprising two or more cyclocarbonate groups and at least one compound (B) comprising two or more amine groups, preferably primary amines. These compounds (A) and (B) will be described in more detail below.

Preferably, the compound (A) having two or more cyclocarbonate groups and the compound (B) having two or more amine groups have a functionality greater than or equal to 2, more preferably 2 to 5, so as to avoid the formation of linear PHUs.

The functionality of the compounds (A) and (B) must lead to crosslinking. In the compound (A) having two or more cyclocarbonate groups, the cyclocarbonate groups have 5, 6 or 7 atoms.

The reaction between at least one compound (A) having two or more cyclocarbonate groups and at least one compound (B) having two or more amine groups is aminolysis. It can be represented for example by the following scheme, in the case where (A) has cyclocarbonate groups with 5 atoms: ## STR1 ## ## STR2 ## - NH n H2N-R2 (NI-12) Compound (B) C) Compound (A) ## STR2 ## wherein n is from 1 to 100 O ## STR5 ## wherein R "and R" 'represent a linear or branched alkylene group, or arylene optionally comprising in the chain, one or more O, N and / or S heteroatoms. This reaction (urethanization) gives molecules comprising at least one urethane (or carbamate) bond and at least one hydroxyl group. Since the primary amine can open cyclocarbonate in two different ways, primary alcohols and / or secondary alcohols are formed. Urethanization can be carried out in the presence of various organic, organometallic or mineral catalysts well known in the art.

This reaction may be carried out at a temperature of from -20 to 200 ° C, preferably from 50 to 150 ° C under atmospheric pressure. Said polyhydroxyurethane (s) used in the composition according to the invention preferably contains (s) 10-100% by weight of urethane groups and 0-90% by weight of groups resulting from the reaction of epoxy with an amine. these percentages being expressed relative to the weight of the polyhydroxyurethane. The binder which comprises one or more polyhydroxyurethanes is preferably present in an amount ranging from 5 to 99% by weight, better still from 10 to 90% by weight, and still more preferably from 15 to 50% by weight relative to the total weight of the composition. The cork or cork-based material and the binder are preferably present in the composition according to the invention in a weight ratio of cork or cork-based material on a binder ranging from 0.01 to 20, better still from 0.1 to 10. In particular, the composition is free from isocyanate, that is to say that it comprises 0% by weight of isocyanate relative to the total weight of the composition. By "isocyanate" is meant any compound including an -NCO- function. The binder may further comprise at least one polyepoxide resulting from the admixture of one or more compounds (D) having two or more epoxy groups with one or more compounds (B) having two or more amine groups.

When at least one polyepoxide is present in the binder, it (they) is (are) present (s) preferably in an amount ranging from 0 to 90% by weight, better still from 1 to 30% by weight relative to the total weight binder. The polyepoxides optionally used in the composition according to the invention are prepared from non-highly toxic raw materials, better derived from biomass. Compounds (D) having two or more epoxy groups and compounds (B) having two or more amine groups that may be used will be described below in more detail.

The reaction between at least one compound (D) comprising two or more epoxy groups and at least one compound (B) comprising two or more amine groups can be represented for example by the following scheme: ## STR2 ## i ~ \ / N. (, 0) + ri2N. (1 \ 11-12) ## STR2 ## wherein R is a compound (D) in which x varies from 1 at 4 and y ranges from 1 to 9, and R'1 and R2 denote, independently of one another, a divalent, saturated or unsaturated, linear or branched, or cycloaliphatic or aromatic, hydrocarbon-based chain which may comprise at least one heteroatom such as O, N and S, and which may be substituted. This reaction may be carried out at a temperature of from -20 to 250 ° C, more preferably from 50 to 150 ° C, at atmospheric pressure. This reaction can be carried out in the presence of a catalyst such as a tertiary amine such as triethylamine, or aminophenol, or a catalyst well known in the art. The composition according to the invention may further comprise one or more biobased additives or not, preferably biobased. This additive or these additives can in particular contribute to the homogeneity of the structure. They can also have hydrophobic properties. Preferably, the additive (s) is (are) chosen from homopolymers or copolymers of which at least one of the monomers is chosen from vinylidene chloride or fluoride, vinyl chloride, metacrylonitrile, acrylonitrile, C1-5 alkyl methacrylate, such as methyl methacrylate, styrene and ethylene; cellulose polymers; latexes (emulsion of polymer particles) such as, for example, polyisoprene, ethylene / vinyl acetate, styrene / acrylic acid or styrene / butadiene latices; silicone oils; paraffins; natural waxes; porogenic agents; glass beads such as those sold by Poraver or those sold by 3M under the reference "bubble glass"; and their mixtures. As examples of homopolymers or copolymers having at least one particular monomer, mention may especially be made of vinylidene chloride homopolymer, vinylidene chloride / vinylidene fluoride / vinyl chloride / acrylonitrile copolymers, and acrylonitrile / methyl methacrylate copolymers. acrylonitrile / methyl methacrylate / methacrylonitrile copolymers, styrene / acrylonitrile copolymers, styrene / ethylene-butylene / styrene copolymers (or SEBS) and homopolymers or copolymers of ethylene. In a preferred embodiment, the additives may be in the form of cellular structures, and more particularly in the form of particles having an average size of less than 500 μm. When one or more additives is or are present, their amount may vary from 0.1 to 20% by weight, better still from 1 to 10% by weight relative to the total weight of the composition.

The invention also relates to the composition comprising: - cork or a material based on cork, - at least one compound (A) comprising two or more cyclocarbonate groups, and - at least one compound (B) comprising two or more than two amine groups, - optionally at least one compound (D) comprising two or more epoxy groups and optionally at least one additive as described above, preferably biosourced. Preferably, the compounds (A) having two or more cyclocarbonate groups may result from the transesterification or esterification of an ester or polycarboxylic acid, with glycerol carbonate or a carbonate with 6 or 7 atoms, or by chemical insertion of the CO2 on a compound containing at least one cyclic ether group, and more particularly on a compound (D) containing two or more epoxy groups, or alternatively by adding a cyclocarbonate bearing double ethylenic functional groups. The invention also relates to a process for preparing the composition according to the invention. It comprises the following steps: (i) mixing the cork or the cork material with at least one compound (A) having two or more cyclocarbonate groups and at least one compound (B) having two or more groups amines, at a temperature ranging from 0 to 150 ° C, preferably from 10 to 50 ° C, under atmospheric pressure, for a period of time ranging from 5 to 120 minutes, preferably from 10 to 60 minutes; and (ii) heating at a temperature of from -20 to 200 ° C, preferably from 50 to 150 ° C, at atmospheric pressure, for a period of from 15 to 150 minutes, preferably from 30 to 120 minutes. In step (i), at least one compound (D) having two or more epoxy groups can also be introduced.

In a particular embodiment, the compound (A) will be mixed with the compound (B) in excess, then the compound (D) will be added. The process according to the invention may further comprise a preliminary step (io) of preparing compound (A) comprising two or more cyclocarbonate groups: by transesterification or esterification of an ester or polycarboxylic acid (A '), with glycerol carbonate or a carbonate with 6 or 7 atoms; or by chemical insertion of CO2 on a molecule containing at least two cyclic ether groups such as an oxirane or an oxetane; or else - by addition of a cyclocarbonate bearing double ethylenic functions such as allyl or propenyl, and a dithiol. This step (io) can be done just before step (i). The use of glycerol carbonate of partially or completely biobased origin in a transesterification or esterification leads to compounds (A) comprising biobased 5-membered cyclocarbonate groups, as indicated below: ## STR2 ## in which: R represents H or a C1-C5 alkyl group, such as methyl and ethyl, R "1 denotes a saturated or unsaturated, linear aliphatic hydrocarbon chain; or branched, or cycloaliphatic or aromatic, may comprise at least one heteroatom such as O, N and S, and may be substituted, and x 'ranges from 2 to 6, and preferably from 2 to 4. This reaction is made at a temperature between -20 and 200 ° C. The polycarboxylic esters or acids (A ') used in the (trans) esterification preferably comprise 2 or more carboxy groups, more preferably 2 to 6, more preferably 2 to 4 carboxy groups. They may be chosen from: - aromatic acids or esters, such as: o phthalic acid or ester (ortho, meta or para) R-O 0 0, RR, O oo the acid or trimellitic ester R, 0 0 0 Wherein the acid or pyromellitic ester R, R 0 0, R 0 0 3 OR the aw diacids or diesters of formula: R 'RO 0 O wherein R'3 denotes an alkylene group preferably C1-20, preferably C3-15 cycloalkylene, preferably C6-18 aromatic, which may contain an oxygen, nitrogen or sulfur atom, - aliphatic acids or esters such as: o dicarboxylic acids or diesters of the formula: wherein R represents an integer ranging from 2 to 20, wherein the tartaric and citric acids or esters are in the form of diacid or diester polyesters of formula: ## STR2 ## Wherein R'4 and R'5 are each independently of one another an alkylene group, preferably one in which R'4 and R'5 are independently C1-20, cycl preferably C -C 15 alkylene, preferably C 6 -C 18 aromatic, which may carry substituents such as C 1 -C 5 alkyl, optionally containing one or more heteroatoms such as O, N and / or S, and n is 1 to 50, better still 1 at 20, where the polybutadienes diacids or diesters telecheliques, the grafted acid copolymers such as poly (acid (meth) acrylic) and poly (itaconique acid) o the fatty acids, oils and derivatives: - the modified oils of formula: In which R 6 represents a linear or branched C 1 -C 5 alkylene group, such as methylene and ethylene, Me denotes the methyl group, 1 is an integer ranging from 1 to 10, m is a number; integer ranging from 1 to 3, and p is an integer ranging from 1 to 10, with the proviso that 1 + 3m + p = 17, dimers and trimers of C36-54 fatty acids, of formulas: ooo such as sold by the company Croda ^ polymeric diacids such as suberin, OH Envelope In a particular embodiment of the invention, the esters or polycarboxylic acids used in the (trans) esterification are modified in a particular embodiment of the invention. are chosen from: dicarboxylic acids or diesters of formula: ## STR2 ## wherein r represents an integer ranging from 2 to 20, diacid or diester polyesters of formula: In which R '4 and R' 5 each independently of one another represents an alkylene group, preferably a C 1-20, cycloalkylene group, preferably a C 3-15, aromatic group; preferably C6-18, which may carry substituents such as C1-C5alkyl, optionally containing one or more heteroatoms such as O, N and / or S, n is from 1 to 50, more preferably from 1 to 20; , and o dimers and trimers of C36-54 fatty acids, of formulas: ## STR2 ## In all the formulas below R 1 is H, C 1 -C 2 alkyl, such as methyl or ethyl. Another method for preparing compounds (A) comprising two or more cyclocarbonate groups is to insert CO2 in a compound containing at least two cyclic ether groups, and more particularly in a compound (D) containing two or more groups epoxy, preferably from 2 to 5, more preferably 2 or 3 epoxy groups. For example, this carbonation process can be carried out in dimethylformamide (DMF) at 80 ° C. under 12 bar of CO 2 for 15 hours. Compounds (D) containing two or more epoxy groups, may themselves be prepared from a polyol comprising two or more hydroxy groups, preferably from 2 to 5 hydroxy groups, and epichlorohydrin, epibromohydrin, or glycidol, or also by the method of allylation and oxidation. The reaction from an alcohol and epichlorohydrin, epibromohydrin or glycidol can be carried out at a temperature ranging from -20 to 150 ° C, preferably from 0 to, 120 ° C.

Examples of polyols comprising two or more hydroxyl groups that may be used in the invention are chosen in particular from: mononuclear aromatic alcohols, such as: o resorcinol HO OH o hydroquinone HO o vanillin and its derivatives HO OH o phloroglucinol OH o cardanol Ci5H31-n with n = 0, 2, 4 or 6 - lignin derivatives selected from p-coumaryl alcohol, coniferyl alcohol and sinapyl alcohol OH OH OH OH HO o coumarin derivatives (HO x, x = e, gallic acid IOH) - dinucleic aromatic alcohols such as vanillin dimer o, o OH OH o o o o represents a divalent, saturated or unsaturated, linear or branched, or cycloaliphatic or aromatic, aliphatic hydrocarbon chain which may comprise at least one heteroatom such as O, N and S, and which may be substituted, and preferably represents an alkylene group, preferably C 1-20e cycloalkylene preferably C3-15, aromatic preferably C6.18, which may carry substituents such as alkyl preferably C1-s optionally having one or more heteroatoms such as O, N and / or S; polynucleic aromatic alcohols such as: o oligo-styrol whose monomer corresponds to the formula: OH o cardanol phenol OH o phenol products of oils and other polyenes such as polybutadienes. (PB), polyisoprenes (PI), and farnesene, such as those of the formula: ## STR1 ## in which Me denotes the methyl group, 1 is a number integer from 1 to 10, m is an integer from 1 to 3, and p is an integer from 1 to 10, with the proviso that 1 + 3m + p = 17 aliphatic alcohols such as oxidation products dimers and trimers of C36-54 fatty acids, such as: HO HO such as those sold by Croda, o sugars, (oligo) glycerols and isosorbides of formulas ## STR1 ## wherein the diols, polyethylene glycols, polypropylene glycols polybutylene glycols and telechelic hydroxy oligobutadienes, such as those of the formulas (0 Re R8 = ± CH2 + cH, X = 2, 3, 4 with n ranging from 1 to 1000, wherein the polyesters-diols of formula: In which R 9 represents a C 1-20 alkylene preferably C 3 -C 15 cycloalkylene, preferably a C 6-18 aromatic, which may carry substituents such as C 1 -C 5 alkyl, optionally containing one or more heteroatoms such as O, N and / or S, and Rio is a diol, polyethylene glycol, polypropylene glycol, polybutylene glycol or telechelic hydroxy oligobutadiene such as those defined above the polycarbonate diols of the formula, wherein X is from 1 to 1000, R 7 and R '7 each independently of one another preferably a C 1-20 alkylene group, preferably a C 3-15 cycloalkylene, preferably a C 6-18 aromatic, which may carry substituents such as C 1 -C 5 alkyl optionally containing one or more heteroatoms such as O, N and / or Examples of compounds (D) containing two or more preferred epoxy groups, which may be commercial, include: vanillin derivatives of formulas (I) and (II): \ 'o /? (I) the gallic acid derivative of formula (III): epoxidized phloroglucinol, wherein the polyepoxidized cardanol of formula: ## STR5 ## such as that sold under the trade name NC-514 by the company Cardolite, polypropylene glycol diglycidyl ether with n between 1 and 1000, such as that sold under the reference DER 732P by Dow, epoxidized oils and their acid derivatives or epoxidized fatty esters such as epoxidized soybean oils, more particularly those of formula In this embodiment, where M denotes the methyl group, 1 is an integer ranging from 1 to 10, m is an integer ranging from 1 to 3, and p is an integer. ranging from 1 to 10, with the proviso that 1 + 3m + p = 17. By way of example of such oils, there may be mentioned the one sold under the trademark "Vikoflex" by the company Arkema, and the tannins of epoxidized tea and epoxidized catechin Compounds (B) used in the invention There are two or more amine groups, preferably 2 to 10, more preferably 2 to 5 amines. They can be aromatic or aliphatic.

Compounds (B) having two or more amine groups can be obtained by a first allylation of aromatic or aliphatic alcohols as described above, or crotonization or methallylation, followed by a thiol-ene reaction on double bonds with an aminated thiol, for example, cysteamine hydrochloride, in the presence of a thermal or photochemical initiator. The thermal initiator may be of azo type such as azobisisobutyronitrile (AIBN). By way of example of a photochemical initiator, mention may be made of 2-hydroxy-2-methyl-1-phenylpropan-1-one such as that sold under the trade name Darocur 1173 or bis (2). 4,6-trimethylbenzoyl) -phenylphosphine oxide, such as that sold under the trade name Irgacure 819. By way of examples of compounds (B) comprising two or more amine groups, mention may in particular be made of oil derivatives. of the formula: ## STR2 ## wherein R 4 denotes a linear or branched C 1 -C 5 alkylene group, such as methylene and ethylene, Me denotes the methyl group, 1 is an integer ranging from 1 to 10, m is a integer from 1 to 3, and p is an integer from 1 to 10 with the proviso that 1 + 3m + p = 17; polybutadiene derivatives bearing -S-R4-NH2 groups, R4 denoting an alkylene group C1.5, linear or branched, such as methylene and ethylene, allylamine derivatives of formula: H2N-R4 desi C1-5 alkylene group, linear or branched, such as methylene and ethylene; trimethylolpropane derivatives of formula: ## STR2 ## wherein R 4 denotes a linear or branched C 1 -C 5 alkylene group, such as methylene and ethylene, pentaerythritol derivatives of the formula (HO-CH 2) -C + CH 2 -O-C 3 H 6 -S-R 4 -NH 2 x 4-x with O <x <2, and R 4 denoting a C 1 -C 5 alkylene group; , linear or branched, such as methylene and ethylene, the cardanol derivatives of formula: HO, R 4 -NH 2) S, NH 2 in which R 4 denotes a linear or branched C 1 -C 5 alkylene group, such as methylene and ethylene , 1 is an integer from 1 to 10, m is an integer from 1 to 3, p is an integer from 0 to 10, and q ranges from 0 to 1; allyl cardanol derivatives of formula: Wherein R4 denotes R4 NH2 a linear or branched C1-5 alkylene group, such as methylene and ethylene, 1 is an integer ranging from 1 to 10, m is an integer ranging from 1 to 3, p is an integer ranging from 0 to 10, and q is from 0 to 1. The allyl vanillin derivatives of formulas: R4 denoting a linear or branched C1-C5 alkylene group, such as methylene and ethylene; the allylated gallic acid derivative of formula: ## STR2 ## (HO with 0 <x <2, and R4 denoting a C1-C5 alkylene group, linear or branched; such as methylene and ethylene, allylated tannin derivatives, such as catechol of the formula: ## STR2 ## where R 4 denotes a linear or branched C 1-5 alkylene group, such as methylene and ethylene.

By way of examples of other compounds B which can be used in the invention and which are commercially available or which naturally have amino compounds, mention may in particular be made of a phenalkamine of formula: ## STR2 ## R5: - ("" CF 1 -C -C Fir-N) .C112-C1-12- x between 0 and 5 11 x -ECH2- ± including between 2 and 12 Y such as, for example, that sold under the name commercial NX-5454 by the company Cardolite; the furan derivative of formula: NH 2 H 2 N polylysine; chitosan derivatives and their derivative oligomers; dimers and trimers of fatty acids modified to amines and amidoamines, such as those sold by Croda, of formulas: ## STR2 ## -N-R 5 -NH 2 H and R 5 being defined as above; amidoamines such as those sold under the trade name Epikure by the company Momentive; polyethyleneimines H2N NH2 with n ranging from del to 10, such as tetraethylenepentamine (TEPA, n = 3) and triethylenetetramine (TETA, n = 2); polyether amines, such as that sold under the trade name Jeffamine by the company Huntsman CH3 0 Y, v,> NH2 2N7 ^,, CH3H2NN CH3CH3 (CH2) x (CH2) xO NH2 CH3 tySH2 NH2 Wherein X, y, z and n ranging from 1 to 1000, and the diamines of formula H2N.t..alpha. two or more preferred amine groups are chosen in particular from: cardanol derivatives of formula: HO R4 NH2 in which R4 denotes a C1-5 alkylene group, linear or branched, such as methylene and ethylene, 1 is a whole number ranging from 1 to 10, m is an integer ranging from 1 to 3, p is an integer ranging from 0 to 10, and q ranges from 0 to 1, the allyl cardanol derivatives of formula: ## STR3 ## Wherein R4 denotes a C1-5 alkylene group, linear or branched, such as methylene and ethylene, 1 is an integer ranging from 1 to 10, in is an integer ranging from 1 to 3, p is a integer from 0 to 10, and q ranges from 0 to 1; the phenalkamines sold by the company Cardolite, of formula: R4 R5: CH2-H2-N) -C H2-C H2- x between 0 and 5 x 29 OH HH C15H31-n n = 0.2.4 or6 -ECH2 - + including between 2 and 12 Y dimers and trimers of fatty acid modified amines and amidoamines such as those sold by Croda, of formulas: 0 G = NH2; R ~ defined as above and the polypropylene glycol diamine or triamine such as that sold under the trade name Jeffamine as Jeffamine D400 or Jeffamine T403 by the company Huntsman, represented by the formula x + y + z = 5 or 6 ry; \, An object of the invention relates to the composition obtainable by the process as described above. The subject of the invention is also a method for manufacturing stoppers using a composition according to the invention. For example, the composition according to the invention can be used in the manufacture of a technical stopper such as "1 + 1", "2 + 2", "0 + 2" and "0 + 1", or agglomerated or microagglomerated plugs. By "1 + 1" is meant a stopper whose body is made of agglomerated cork granules with an adhesive which will be within the scope of the invention at least one polyhydroxyurethane described above, while the two ends are each composed of a washer made of natural cork, said washers being obtained by casing a piece of cork whose thickness corresponds to that of the washers. The casing consists in taking a piece of cork by means of a punch. The cap "2 + 2" consists of an agglomerated part and with two washers at the ends, while the caps "0 + 2" for the champagne or the caps "0 + 1" for the effervescent do not include a washer with one end and 2 or 1 washer (s) at the other end, respectively. The composition according to the invention may, for example, be used in the method of manufacturing stoppers as described in application FR 2 672 002. Still another object is a stopper capable of being obtained by the manufacturing process.

The stopper obtained from a composition according to the invention has physical properties at least equivalent to or even greater than those of a natural cork stopper and that of corks containing at least a portion of agglomerated cork based on binder . The properties of such a plug are characterized by the absence of water absorption characterized by the measurement of imbibition and the mechanical properties of the plug. The imbibition measurement is made by immersing corks in boiling water for 15 min. The imbibition measurement must be less than 20%, preferably 18% and even better less than 15%. The mechanical properties are characterized by the compressive force to compress it or by the force that the stopper returns to the neck of the bottle commonly called the springback.

As an indication, plugs with a diameter of between 26 and 31 mm are characterized by the measurement of compression pressure. This measurement is done by compressing a stopper with a piston that moves at a speed of 1 Omm / min, to a diameter between 15 and 16 mm. The compression value is brought back to the cylindrical surface of the plug. This must be between 15 and 60 N / cm 2 and preferably between 25 and 60 N / cm 2 according to the diameters of the plugs. As an indication, plugs with a diameter of between 20 and 25 mm are characterized by measuring the return force exerted by the plug after the plug has been compressed to a diameter of 15 to 16 mm, and then returned to a diameter between 18 to 21 mm and held for 3 minutes. The force obtained is returned to the cylindrical surface of the plug to obtain the springback. This must be understood for the still wine corks (diameter of the order of 24 mm) between 0.8 and 5 N / cm2, better ranging from 1.5 to 4.5 N and preferably 2 to 4 N. L another subject of the invention is the use of a polyhydroxyurethane resulting from the mixing of one or more compounds (A) having two or more cyclocarbonate groups with one or more compounds (B) having two or more amine groups as described above, as a binder for cork or a cork-based material. This polyhydroxyurethane may be used in combination with at least one polyepoxide resulting from the mixture of one or more compounds (D) having two or more epoxy groups with one or more compounds (B) having two or more amine groups, as described above, as a binder for cork or a cork-based material.

In a first particular embodiment, the compound (B) is used in excess relative to the compound (A). In a second embodiment, the compound (A) is used in excess with respect to the compound (B). The following examples are given purely by way of illustration of the present invention. EXAMPLES Example 1: Preparation of a compound (A) Polypropylene glycol diglycidyl ether was reacted with CO2 under a pressure of 12 bar in the presence of dimethylformamide (DMF) at 80 ° C for 15 hours. A compound (A) having a percentage of carbonate groups ranging from 25 to 100% by weight relative to the weight of the compound (A) is obtained.

Example 2: Preparation of PHU binders PHU binders were prepared from the following ingredients listed in Table 1 below: Table 1 Binder Compound (A) Compound (B) Crosslinker I Diglycidyl ether Phenalkamine triglycidyl ether trimethylpropane polypropylene carbonated glycol * II Diglycidyl ether Polypropylene triglycidyl trimethylolpropane ether of polypropylene glycol triamine glycol carbonate * * of Example 1 Mixtures of a compound (A) and a compound (B) having two or more than two were used amine groups as indicated in Table 1, with 0 to 30% by weight of crosslinking agent relative to the total weight of the carbonate (compound (A)). In particular, binders II were prepared by mixing 1 g of compound (A) and 0.46 g of compound (B); the addition of crosslinker may be up to 30% by weight relative to the carbonate. These binders were then crosslinked at 120 ° C. for 1 hour. The II binders without cork flour were then characterized using the methods given below. Thermal and mechanical analyzes were performed on the PHU binders obtained. For thermogravimetric analysis, ten milligrams of binder was dynamically tested under nitrogen at 10 ° C / min. For the glass transition measurement, differential scanning calorimetry (DSC) was performed with a dynamic program at 20 ° C / min under nitrogen flow. For mechanical analyzes, deformation was applied to the sample at 3 ° C / min at 1 Hz. The results are as follows: a mass loss temperature of 30% of the order of 300 ° C .; a glass transition temperature of the order of 0 ° C; a mechanical transition temperature also of the order of 10 ° C; an elastic modulus of the order of 3.8 MPa; and a glassy module of the order of 3900 MPa; Example 3 A plug was made by a molding process from cork flour and binder H having 25% urethane groups, prepared in Example 2. A 70% by weight mixture was compacted with respect to weight of the mixture, cork flour having a particle size ranging from 0.25 to 1.5 mm, and 30% by weight, relative to the weight of the mixture, of binder II prepared in Example 2, in a tube which was closed and put in an oven at a temperature of 120 ° C. The molding time is adapted according to the reactivity of the polyhydroxyurethane binder and can vary from 30 minutes to 2 hours. In particular, the molding time is 2 hours in these examples.

Compact caps that do not crumble on demolding were obtained. The plugs obtained with the binder II prepared in Example 2 were then characterized with the methods for measuring the imbibition and the pressure in compression, indicated above. The results are summarized in Table 2 below. Table 2 Density density (g / dm3)% Pressure Compressive imbibition (N / cm2) Sample 1 330 17% 45 Sample 2 356 12% 42

Claims (22)

REVENDICATIONS1. A composition comprising cork or a cork material and a binder which comprises one or more polyhydroxyurethanes resulting from the admixture of one or more compounds (A) having two or more cyclocarbonate groups with one or more compounds (B) comprising two or more amine groups. 2. Composition according to claim 1, characterized in that it contains from 1 to 95% by weight of cork or a cork-based material, relative to the total weight of the composition. 3. Composition according to claim 1 or 2, characterized in that the (s) polyhydroxyurethanes are prepared from biosourced raw materials. 4. Composition according to any one of the preceding claims, characterized in that the polyhydroxyurethane (s) comprises (s) 10-100% by weight of urethane groups and 0-90% by weight of groups resulting from the reaction of epoxy with an amine, these percentages being based on the weight of the polyhydroxyurethane. 5. Composition according to any one of the preceding claims, characterized in that it contains from 5 to 99% by weight of binder which comprises one or more polyhydroxyurethanes, relative to the total weight of the composition. 6. Composition according to any one of the preceding claims, characterized in that the weight ratio cork or cork-based material on binder which comprises one or more polyhydroxyurethanes ranges from 0.01 to 20. 7, Composition according to any one of the preceding claims, characterized in that it is free of isocyanate. 8. Composition according to any one of the preceding claims, characterized in that the binder further comprises one or more polyepoxides resulting from the mixture of one or more compounds (D) comprising two or more epoxy groups with one or more compounds (B) having two or more amine groups. 9. Composition according to claim 8, characterized in that the binder comprises the polyepoxide or polyepoxides in an amount ranging from 0 to 90% by weight relative to the total weight of the binder. A composition comprising: cork or a cork material, at least one compound (A) having two or more cyclocarbonate groups, and at least one compound (B) having two or more amine groups. 11. Composition according to any one of the preceding claims, characterized in that the compounds (A) comprising two or more cyclocarbonate groups result from the transesterification or esterification of an ester or polycarboxylic acid, with glycerol carbonate or a carbonate with 6 or 7 atoms or by chemical insertion of CO2 on a compound containing at least one cyclic ether group, and more particularly on a compound (D) containing two or more epoxy groups, or by addition of a carrier cyclocarbonate double ethylenic functions. 12. Composition according to any one of the preceding claims, characterized in that it comprises one or more additives, preferably biosourcés. 13. Composition according to claim 12, characterized in that the additive (s) is (are) chosen from homopolymers or copolymers of which at least one of the monomers is chosen from vinylidene chloride or fluoride, vinyl, metacrylonitrile, acrylonitrile, C1-5 alkyl methacrylate, styrene and ethylene; cellulose polymers; latexes; silicone oils; paraffins; natural waxes; porogenic agents; glass beads and mixtures thereof. 14. The composition of claim 12 or 13, characterized in that the additive (s) is (are) present in an amount ranging from 0.1. to 20% by weight, better from 1 to 10% by weight relative to the total weight of the composition. 15. Composition according to claim 11, characterized in that the polycarboxylic esters or acids are chosen from: dicarboxylic acids or diesters of formula RO (CH2), OR in which r represents an even number ranging from 2 to 20; diacid or diester polyesters of formula: wherein R '4 and R' 5 each represent, independently of one another, an alkylene group, preferably C1-20, preferably C3-C15 cycloalkylene, preferably C6-18 aromatic, optionally substituted with substituents such as C1-C6alkyl, and optionally containing one or more heteroatoms such as O, N and / or S, n is from 1 to 50, more preferably from 1 to 20, and dimers or trimers of C36-54 fatty acids, of formulas: wherein R is H, C1-C2 alkyl, such as a group methyl or ethyl. 16. Composition according to claim 11, characterized in that the compounds (D) containing two or more epoxy groups are chosen from: vanillin derivatives of formulas (I) and (11): OR OR 0 RO OR ORo Wherein the gallic acid derivative of formula (III): epoxidized phloroglucinol polyepoxidized cardanol of formula: polypropylene glycol diglycidyl ether epoxidized oils and their acid derivatives or epoxidized fatty esters, and epoxidized tea tannins and epoxidized catechins. 17. Composition according to any one of claims 1 to 16, characterized in that the compounds (B) comprising two or more amine groups are chosen from: - the oil derivatives of formula: 171H2 s-R4 in which R 4 denotes a linear or branched C 1 -C 5 alkylene group, such as methylene and ethylene, Me denotes the methyl group, 1 is an integer ranging from 1 to 10, m is an integer ranging from 1 to 3, and p is an integer ranging from 1 to 10, with the proviso that 1 + 3m + p = 17 polybutadiene derivatives bearing -S-R 4 -NH 2 groups, R 4 denoting a linear or branched C 1 -C 6 alkylene group, such as methylene and ethylene ; Allylamine derivatives of the formula: H 2 N -R 4 R 4 denoting a linear or branched C 1 -C 5 alkylene group, such as methylene and ethylene; trimethylolpropane derivatives of the formula: Res N H2 15 NH2 R4 denoting a linear or branched C1-C5 alkylene group, such as methylene and ethylene; pentaerythritol derivatives having the formula linear or branched HO-CH 2 -) - C + CH 2 -O-C 3 H 6 -S-R 4 -NH 2) 4-x 40, such as with 0 <x <2, and R 4 denoting a group C1-5 alkylene, methylene and ethylene; the cardanol derivatives of formula: embedded image in which R 4 denotes a linear or branched C 1 -C 5 alkylene group, such as methylene and ethylene, 1 is an integer ranging from from 0 to 10, and q ranges from 0 to 1; 1 to 10, m is an integer ranging from 1: R43_, NpH2e) st an integer - the allyl cardanol derivatives of formula: H2N-R4 f R4 NH2 wherein R4 denotes a C1-5 alkylene group, linear or branched, such as methylene and ethylene, 1 is an integer from 1 to 10, m is an integer from 1 to 3, p is an integer from 0 to 10, and q ranges from 0 to 1; allylated vanillin derivatives of formulas: R 4 -NH 2 O 5 R 4 O 0 e -H 2 R 4 denotes a linear or branched C 1 -C 5 alkylene group, such as methylene and ethylene; the allylated gallic acid derivative of formula: ## STR1 ## with O <x <2, and R 4 denoting a C 1 -C 5 alkylene, methylene and ethylene group; allylated tannin derivatives, such as catechin R4 /.,., H2N S of formula: linear or branched, such as R.sub.4 H.sub.2 N.sub.4, R.sub.4 R.sub.4 denoting an alkylene methylene and ethylene group; a phenalkamine of formula C1.5, linear or branched, such as H, H n = 0, 2, 4 or 6 R5: "CE12-CH2-14C1-12-CH2- x between () and 5 Fi xy between 2 and 12 Y - the furan derivative of the formula: NH 2 polylysine, the chitosan derivatives and their oligomers, the modified fatty acid dimers and trimers to amines and amidoamines of the formula ## STR1 ## H and R5 denoting - (CH2-CH2-NH) '- CH2-CH2- with x ranging from 0 to 5, - (C112) y- with y being between 2 and 12, or arnidoamines, polyethylene imines IH H2N - NN H2 with n ranging from 1 to 10, the polyether amines H2N NI-12 CH3 1-12N-71.0, ## STR3 ## wherein X, y, z and n ranging from 1 to 1000; and the diamines of formula H 2 N 1..yriNtFl 2 3a 1 2 18. Process for the preparation of the composition according to any one of the preceding claims, characterized in that it comprises the following steps: (i) mixing the cork or the material with. cork base with at least one compound (A) having two or more cyclocarbonate groups and at least one compound (B) having two or more amine groups, at a temperature ranging from 0 to 150 ° C, preferably from 10 to 50 ° C, at atmospheric pressure, for a period ranging from 5 to 120 minutes, and (ii) heating at a temperature ranging from -20 to 200 ° C, preferably from 50 to 150 ° C, under atmospheric pressure for a period ranging from 15 to 150 minutes. 19. Process according to claim 18, characterized in that it comprises an additional preliminary step (10) of preparing the compound (A) comprising two or more cyclocarbonate groups by transesterification or esterification of an ester or monohydric acid. or polycarboxylic, with glycerol carbonate or a carbonate with 6 or 7 atoms, or by chemical insertion of CO2 on a compound containing at least one cyclic ether group, and more particularly on a compound (D) containing two or more groups epoxy, or by addition of a cyclocarbonate bearing double ethylenic functions. 20. The method of claim 18, characterized in that at least one compound (D) having two or more epoxy groups is introduced in step (i). 21. The method of claim 20, characterized in that the compound (A) is mixed with the compound (B) in excess, and the compound (D) is added. 22. Composition characterized in that it is obtainable by the method according to any one of claims 18 to 21.23. A process for producing a stopper comprising the process for preparing the composition as claimed in any of claims 18 to 21. 24. Use of the polyhydroxyurethane resulting from the blending of one or more compounds (A) having two or more two cyclocarbonate groups with one or more compounds (B) having two or more amine groups, as a binder of cork or a cork material. Use according to claim 24, in combination with at least one polyepoxide resulting from mixing one or more compounds (D) having two or more epoxy groups with one or more compounds (B) having two or more than two amine groups. 26. Use according to claim 25, characterized in that the compound (B) is in excess relative to the compound (A), or the compound (A) is in excess relative to the compound (B).