WO2015107113A1

WO2015107113A1 - Combination of cork / polyhydroxyurethane binder and method for manufacturing same

Info

Publication number: WO2015107113A1
Application number: PCT/EP2015/050683
Authority: WO
Inventors: Emilie DARROMAN; Clothilde Balbusquier; Sylvain Caillol; Bernard Boutevin; Rémi Auvergne; Christophe Loisel; Dominique Tourneix
Original assignee: Diam Bouchage; Centre National De La Recherche Scientifique (Cnrs); Ecole Nationale Supérieure De Chimie De Montpellier; Université Montpellier 2 Sciences Et Techniques
Priority date: 2014-01-15
Filing date: 2015-01-15
Publication date: 2015-07-23
Also published as: EP3094664A1; FR3016367A1; FR3016367B1

Abstract

The invention relates to a composition that includes cork or a cork-based material and a binder which includes at least one polyhydroxyurethane prepared using raw materials that are not highly toxic, preferably from biomass. In particular, the polyhydroxyurethane binder is synthesised from at least one compound (A) comprising two or more cyclocarbonate groups and at least one compound (B) comprising two or more amino groups. The invention also relates to the method for preparing said composition.

Description

Cork / binder combination based on polyhydroxyurethane and its preparation process

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 process for producing a cork and the use of a polyhydroxyurethane as an adhesive for cork or a cork 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 are used 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.

Indeed, the harvest of cork is limited to a few areas of the world in which cork oak cultivation is profitable, and the production of natural cork scarcely 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, the polyurethane coils 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 di-isocyanate 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 purpose of the present invention, the term "non-highly toxic raw materials" is intended to mean raw materials which are not carcinogenic-mutagenic-reprotoxic (or CMR) class 1 A, 1 B and 2 molecules.

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 preferably partially or completely biobased. For the purpose of the present invention, the term "bio sourced" is intended to mean a compound derived from biomass which has or has not undergone chemical treatment, and which is not classified CMR, classes 1A, 1B and 2. Examples of biomass include plant, tree, vine, fruit, vegetable or algae extracts.

The polyhydroxyurethanes result from the reaction between a compound having two or more amino 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) in the β 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 to 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) having two or more than two cyclocarbonate groups with one or more compounds (B) having two or more amino groups.

Another object is a composition comprising cork or a cork-based material, one or more compounds (A) having two or more cyclo-carbonate groups and one or more compounds (B) having two or more amino groups. .

In a preferred embodiment of the invention, the compounds (A) and (B) are non-highly toxic, and preferably bio-sourced.

Another object of the invention is a process for the preparation of 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 ...".

In addition, 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 mixing of one or more compounds (A) having two or more cyclocarbonate groups with one or more compounds (B) having two or more amino groups.

The cork or the cork-based material that can be used in the invention is especially 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 may be partially or completely bio-sourced. They are prepared from raw materials preferably bio sourced as specified above, namely raw materials from biomass and not being classified CMR, classes 1A, 1B and 2.

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

Preferably, the compound (A) having two or more cycloalkyl groups and the compound (B) having two or more amino 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 amino groups is amino-lysis. It can be represented for example by the following scheme, in the case where (A) has cyclo carbonate groups with 5 atoms:

Compound (A) Compound (B)

R ', R "and R'" representing a linear or branched alkylene group, or arylene optionally comprising in the chain, one or more heteroatoms O, N and / or S.

This reaction (urethanization) gives molecules containing 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 performed 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 10 to 100% by weight of urethane groups and 0 to 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 mixing one or more compounds (D) having two or more epoxy groups with one or more compounds (B) having two or more amino 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 preferably 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 amino 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 amino groups can be represented for example by the following scheme:

Compound (D) compound (B) wherein x is from 1 to 4 and y ranges from 1 to 9, and

R 'i and R ₂ denote, independently of one another, 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 can 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 an aminophenol, or a catalyst well known in the art.

The composition according to the invention may furthermore comprise one or more organic additives, whether sourced 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, C 1 -C 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 μπι.

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 cork-based material,

at least one compound (A) having two or more cyclocarbonate groups, and at least one compound (B) having two or more amino groups,

optionally at least one compound (D) having two or more epoxy groups and

optionally at least one additive as described above, preferably biobased.

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 C0 ₂ 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 method for preparing the composition according to the invention. It includes 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 amino groups, at a temperature of 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, under atmospheric pressure, for a time ranging 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, and then the compound (D) will be added.

The process according to the invention may further comprise a preliminary step (io) of preparing compound (A) having two or more cyclocarbonate groups: • by transesterification or esterification of an ester or polycarboxylic acid (Α '), with glycerol carbonate or a carbonate with 6 or 7 atoms; or

By chemical insertion of C0 ₂ on a molecule containing at least two cyclic ether groups such as an oxirane or an oxetane; or

• by addition of a cyclo carbonate bearing double ethylenic functions such as allyl or propenyl, and a dithio l.

This step (i ₀ ) 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 5 - membered bio - sourced cyclo - carbonate groups, as indicated below:

wherein :

R represents H or a C 1 -C 5 alkyl group, such as methyl and ethyl,

R "i denotes a 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

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 esters or polycarboxylic acids (Α ') 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 can be chosen from:

aromatic acids or esters such as:

ol 'phthalic acid or ester (ortho, meta or para)

ο acid or trimellitic ester

o the pyromellitic acid or ester

the α-ω diacids or diesters of formula:

wherein R ' ₃ denotes an alkylene group, preferably C ₁ -C 20, preferably C ₃ -C ₅ cycloalkylene, preferably C ₆ -C 18 aromatic, which may contain an oxygen, nitrogen or sulfur atom;

aliphatic acids or esters such as:

the dicarboxylic acids or diesters of formula:

in which r represents an integer ranging from 2 to 20, where the tartaric and citric acids or esters

the diacid or diester polyesters of formula:

wherein R _'4 and R' 5 are each independently of one another, an alkylene group, preferably C1-20 cycloalkylene preferably C3-15, preferably aromatic C ₆ -i8, may bear substituents such as alkyl, preferably C _1-5 , optionally having one or more heteroatoms such as O, N and / or S, and n is 1 to 50, more preferably 1 to 20,

o polybutadienes diacids or telechelic diesters,

o acid-graft copolymers such as poly (acid)

(meth) acrylic) and poly (itaconic acid),

o fatty acids, oils and derivatives:

^■ modified oils of formula:

in which R ₆ represents a linear or branched C _1-5 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 from 1 to 10, provided that l + 3m + p = 17,

^■ dimers and trimers of fatty acids C36-54, of the formulas:

modified undecylenic acid

n being 1 or 2.

In a particular embodiment of the invention, the polycarboxylic esters or acids used in the (trans) esterification are chosen from:

o the dic acids of formula:

in which r represents an integer ranging from 2 to 20, and

diacid or diester polyesters of formula:

in which R ' ₄ and R' ₅ each represent, independently of one another, an alkylene group preferably of C _1-20 , cycloalkylene preferably of C 3-15, aromatic preferably of Ce-is, which can carry substituents such as alkyl preferably C _1-5, optionally containing one or more heteroatoms such as O, N and / or S, n is 1 to 50, preferably 1 to 20, and

the dimers and trimers of C36-54 fatty acids, of formulas:

In all the above formulas, R represents H, a C 1 -C 2 alkyl group, such as a methyl or ethyl group.

Another process for preparing compounds (A) comprising two or more cyclo-carbonate 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 than two epoxy groups, 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, of epibromohydrin, or glycido 1, 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 having two or more hydroxy groups which can be used in the invention are chosen from:

mononucleic aromatic alcohols such as:

o resorcinol

o hydroquinone

o Vanillin and its derivatives

o phloroglucino l o cardanol

o lignin derivatives selected from p-coumaryl alcohol, coniferyl alcohol and sinapyl alcohol

coumarin derivatives

gallic acid

dinuclear aromatic alcohols as

o vanillin dimer

the α -ω diphe

in which R ₃ represents a divalent, saturated or unsaturated, linear or branched, or cycloaliphatic or aromatic, saturated or unsaturated 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 -C ₂₀ , preferably cycloalkylene C3-15, preferably aromatic C-is, which may carry substituents such as alkyl preferably C _1-5 optionally comprising one or more heteroatoms such as O, N and / or S;

polynucleic aromatic alcohols such as:

o the oligo-styrol whose monomer corresponds to the formula:

OH

o

the phenol products of oils and other polyenes such as polybutadienes (PB), polyisoprenes (PI), and farnesene, such as those of formula:

in which Me is methyl, 1 is an 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 l + 3m + p = 17;

aliphatic alcohols such as: the products obtained by oxidation of dimers and trimers of C36-54 fatty acids, such as:

such as those sold by Croda,

the and isosorbides of formulas:

H

diols, polyethylene glycols, polypropylene glycols, polybutylene glycols and telechelic hydroxy oligobutadienes, such as those of formulas:

with n ranging from 1 to 1000,

polyesters-diols of formula

in which R 9 represents a C ₁ -C ₂₀ alkylene, preferably C 3-15 cycloalkylene, preferably C 6-18 alkylene group, which may carry substituents such as C ₁ -C ₅ alkyl, optionally containing one or more several heteroatoms like O, N and / or S, and

Rio is a diol, polyethylene glycol, polypropylene glycol, polybutylene glycol or oligobutadiene hydroxy telechelic such as those defined above,

polycarbonates-diols of formula

in which x is from 1 to 1000,

R ₇ and R _'7 are each independently of one another, an alkylene group, preferably C1-20, preferably C3-15 cycloalkylene, preferably aromatic C ₆ -i8, may carry substituents such preferably C1-5 alkyl, optionally containing one or more heteroatoms such as O, N and / or S.

As examples of compounds (D) containing two or more preferred epoxy groups, which may be commercial, there may be mentioned:

derivatives of vanillin (or coniferyl alcohol) of formulas:

para-coumaryl alcohol derivatives of formulas:

the derivatives of the sinapyl alcohol of formulas:

the gallic acid derivative of the formula

epoxy phloroglucino

polyepoxidized cardanol of formula:

such as that sold under the trade name NC-514 by the company Cardo lite,

polypropylene glycol diglycidyl ether

with n between 1 and 1,000,

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 which 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 is an integer ranging from 1 to 10, with the proviso that l + 3m + p = 17. By way of example of such oils, there may be mentioned the one sold under the brand name "Vikoflex" by the company Arkema; and

epoxidized tea tannins and epoxidized catechins.

The compounds (B) used in the invention comprise two or more amino groups, preferably 2 to 10, more preferably 2 to 5 amino groups. They can be aromatic or aliphatic.

Compounds (B) having two or more amino groups can be obtained by a first allylation of aromatic or aliphatic alcohols as described above, or crotonization or methallylation, followed by a thio-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-phenylpropanone 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 8 19.

By way of examples of compounds (B) comprising two or more amino groups, mention may be made in particular of:

derivatives of oils of formula:

in which R ₄ denotes a C _1-5 alkylene group, linear or branched, 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 from 1 to 10, provided that l + 3m + p = 17; polybutadiene derivatives bearing -SR ₄ -NH ₂ groups, R ₄ denoting a linear or branched C _1-5 alkylene group, such as methylene and ethylene;

the allylamine derivatives of formula:

R ₄ denotes a linear C _1-5 alkylene group

methylene and ethylene;

trimethylolpropane derivatives of formula

R ₄ denotes a linear or branched C _1-5 alkylene group, such as methylene and ethylene;

pentaerythritol derivatives of formula:

HO-CH ₂ -C - (- CH ₂ - O - C ₃ H ₆ - S - R ₄ NH ₂ )

4-x

with 0 <x <2, and R ₄ denotes a linear or branched C _1-5 alkylene group, such as methylene and ethylene;

the cardanol derivatives of formulas (I) and (II):

in which R ₄ denotes a linear or branched C _1-5 alkylene group, such as methylene and ethylene, 1 is an integer ranging from 1 to 10, m is an integer from 1 to 3, p is a number integer from 0 to 10, and q ranges from 0 to 1;

vanillin derivatives (or coniferyl alcohol) of formulas:

the derivatives of the sinapyl alcohol of formulas

the gallic acid derivative of formula:

with 0 <x <2, and

tannin derivatives, such as catechol of formula:

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 commercial or which naturally have amino compounds, there may be mentioned in particular:

a phenalkamine of formula:

R ₅ : x between 0 and 5

re 2 and 12

such as, for example, that sold under the trade name NX-5454 by the company Cardo lite;

the furan derivative of formula:

polylysine;

chitosan derivatives and their derivative oligomers;

dimers and trimers of fatty acids modified to amines and amidoamines, such as those sold by the company Croda, of formulas:

G = NH ₂ ; - ^L - R5 - NH ₂

H

and R5 being defined as above;

amidoamines such as those sold under the trade name Epikure by the company Momentive;

polyethylene-imi

with n ranging from 1 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

with x, y, z and n ranging from 1 to 1000; and

the diamines of formula:

H ₂ N ^ NH ₂

v 'n = 3 to 12

The compounds (B) comprising two or more preferred amino groups are chosen in particular from:

the cardanol derivatives of formulas (I) and (II):

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 1 to 10, m is an integer ranging from 1 to 3, p is a number integer from 0 to 10, and q ranges from 0 to 1;

phenalkamines sold by the company Cardo lite, of formula:

CH ₂ - CH ₂ - N CH ₂ -CH ₂ - x between 0 and 5

H ^x between 2 and 12

O

G = NH ₂ ; -N- R ₅ - NH ₂

H

R ₅ defined as above

and

polypropylene glyco diamine or triamine such as that sold under the trade name Jeffamine as Jeffamine D400 or Jeffamine T403 by Huntsman, represented by the formula:

An object of the invention is the composition obtainable by the method as described above.

Another object of the invention is a method of manufacturing plugs implementing a composition according to the invention.

For example, the composition according to the invention can be used in the manufacture of a technical cap 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 "2 + 2" stopper consists of an agglomerated part and 2 end washers, while the "0 + 2" stoppers for Champagne or the "0+ 1" stoppers for effervescent do not include a washer. 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 process for manufacturing stoppers as described in application FR 2 672 002.

Another obj and still is a plug that can be 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 corks containing at least a portion of agglomerated cork based on a binder. . The properties of such a plug are characterized by the absence of water absorption characterized by the measurement of imbibition as well as the mechanical properties of the plug.

The imbibition measurement is made by immersing plugs in boiling water for 15 minutes. The imbibition measurement should be less than 20%, preferably 18% and even more preferably 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 3 1 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 10mm / min, with 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 depending on 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 / cm ² , better ranging from 1.5 to 4.5 N and preferably 2 to 4 N.

The invention also relates to the use of a polyhydroxyurethane resulting from the mixing of one or more compounds (A) having two or more groups cyclocarbonates with one or more compounds (B) having two or more amino groups, as described above, as binder of cork or of a cork material. This polyhydroxyurethane may be used 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 amino 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 of 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)

Poly (glyco) polypropylene diglycidyl ether was reacted with CO ₂ at 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 shown in Table 1 below: Table 1

* example 1

Mixtures of a compound (A) and a compound (B) having two or more amino groups as shown in Table 1, with 0 to 30% by weight of crosslinking agent based on the weight were used. carbonate total (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 can 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 II having 25% urethane groups, prepared in Example 2.

A mixture of 70% by weight, relative to the weight of the mixture, was compacted of 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, 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 plugs that did 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

Claims

1. 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 amino 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 expressed relative to 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 or more than one compound (B) having two or more amino 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.

10. Composition comprising:

cork or a cork-based material,

at least one compound (A) having two or more cyclocarbonate groups, and

at least one compound (B) comprising two or more amino groups.

1 1. Composition according to any one of the preceding claims, characterized in that compounds (A) comprising two or more cyclo-carbonate groups result from the transesterification or esterification of an ester or polycarboxylic acid, with glycerol carbonate or a carbonate at 6 or 7 atoms or by chemical insertion of C0 ₂ 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 bio-sourced.

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, C ₁ -C ₅ alkyl methacrylate, styrene and ethylene; cellulosic polymers; latexes; silicone oils; paraffins; natural waxes; porogenic agents; glass beads and mixtures thereof.

14. Composition according to claim 12 or 13, characterized in that the additive (s) is (are) present in a quantity ranging from 0.1 to 20% by weight, better still 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:

o the dicarboxy acids formula:

wherein r represents an even number ranging from 2 to 20;

the diacid or diester polyesters of formula:

wherein wherein R _'4 and R' ₅ are each independently of one another, an alkylene group, preferably C-20, preferably C3-15 cycloalkylene, preferably aromatic C ₆ -i8, optionally bearing substituents such as alkyl preferably C _1-5 and optionally comprising one or more heteroatoms such as O, N and / or S, n is 1 to 50, preferably 1 to 20, and o dimers or trimers of acids in C - of formulas:

in which formulas, R represents H, a C1-C2 alkyl group, such as a methyl or ethyl group.

16. Composition according to claim 11, characterized in that the compounds (D) containing two or more epoxy groups are chosen from:

derivatives of vanillin (or coniferyl alcohol) of formulas:

para-coumaryl alcohol derivatives of formulas:

the derivatives of the sinapyl alcohol of formulas:

the gallic acid derivative of formula:

phloroglucinol ep

polyepoxidized cardanol of formula

po lypropylene 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 amino groups are chosen from:

derivatives of oils of formula:

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 1 0, m is an integer ranging from 1 at 3, and p is an integer from 1 to 10, provided that l + 3m + p = 17;

polybutadiene derivatives bearing -SR ₄ -NH _{2 groups} , R ₄ denoting a linear or branched C ₁ -C ₅ alkylene group, such as methylene and ethylene;

derivatives of allylamine of formula: R ₄ denotes a linear or branched C _1-5 alkylene group, such as methylene and ethylene;

trimethylolpropane derivatives of formula:

pentaerythritol derivatives of formula:

HO-CH ₂ -CC - (- CH ₂ -O-C ₃ H ₆ - S-R ₄ NH ₂ )

x ^{4 "x}

with 0 <x <2, and

the cardanol derivatives of formulas (I) and (II):

in which R4 denotes a linear or branched C _1-5 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 ranging from 0 to 10, and q ranges from 0 to 1;

vanillin derivatives (or coniferyl alcohol) of formulas:

the derivatives of the sinapyl alcohol of formulas:

the gallic acid derivative of formula:

with 0 <x <2, and

R.4 denotes a C _1-5 alkylene group, linear or branched, such as methylene and ethylene;

tannin derivatives, such as catechol of formula:

R ₄ denotes a linear or branched C ₁ -C ₅ alkylene group, such as methylene and ethylene;

a phenalkamine of formula:

n = 0, 2, 4 or 6

Rs ^ -CH ₂ - CH ₂ - N | CH ₂ -CH ₂ - where x is between 0 and 5

H ^x

including between 2 and 12

the furan derivative of formula

lylysine;

chitosan derivatives and their oligomers;

dimers and trimers of fatty acids modified to amines and amidoamines of formulas:

R ₅ denotes - (CH ₂ -CH ₂ -NH) _X -CH ₂ -CH ₂ - where x is between 0 and 5, - CH ₂ ) _y - with y between 2 and 12, or

amidoamines;

s polyethylene-imin

with n ranging from 1 to 10

s polyether-amines

H ₂ N

with x, y, z and n ranging from 1 to 1000; and

the diamines of formula:

H ₂ N ^ NH ₂

V 'n = 3 to 12

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 cork material with at least one compound (A) having two or more cyclocarbonate groups and at least one compound (B) having two or more amino groups, at a temperature of from 0 to 150 ° C, preferably from 10 to 50 ° C, under atmospheric pressure, for a time 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 (i ₀ ) of preparing the compound (A) comprising two or more cyclocarbonate groups by transesterification or esterification of an ester or acid mono- or polycarboxylic, with glycerol carbonate or a carbonate with 6 or 7 atoms, or by chemical insertion of C0 ₂ on a compound containing at least one cyclic ether group, and more particularly on a compound (D) containing two or more of two epoxy groups, or by addition of a cyclocarbonate bearing double ethylenic functions.

20. Process according to claim 1 8, characterized in that at least one compound (D) having two or more epoxy groups xy is introduced in step (i).

21. Process according to claim 20, characterized in that the compound (A) is mixed with the compound (B) in excess, and then the compound (D) is added.

22. Composition characterized in that it is capable of being obtained by the process according to any one of Claims 1 to 21.

23. A method of manufacturing a stopper comprising the process for preparing the composition according to any one of claims 1 to 21.

24. Use of the polyhydroxyurethane resulting from the blending of one or more compounds (A) having two or more cyclocarbonate groups with one or more compounds (B) having two or more amino groups, as a binder of cork or a cork-based 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 amino 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).