WO2001011956A1

WO2001011956A1 - Complexes based on dendritic polymers, their use as bioactive agents

Info

Publication number: WO2001011956A1
Application number: PCT/FR2000/002337
Authority: WO
Inventors: Thomas Canova; Sandrine Rochat; Jean-François SASSI
Original assignee: Rhodianyl
Priority date: 1999-08-18
Filing date: 2000-08-18
Publication date: 2001-02-22
Also published as: FR2797563A1; AU7014000A

Abstract

The invention concerns novel bioactive agents, comprising a dendritic polymer and at least a compound based on a biocidal metal or biocidal metal ions. The invention also concerns compositions based on thermoplastic polymers, comprising such agents.

Description

Complexes based on dendritic polymers, their use as bioactive agents

The invention relates to bioactive agents, in particular anti-bacterial, antimicrobial and antifungal agents, comprising a biocidal element. The invention also relates to thermoplastic compositions comprising the bioactive compound.

For many applications, it is sought to limit the development of microorganisms near articles made of thermoplastic material. In the textile fields, for example, it is sought to avoid smelly effects by limiting the development of bacterial flora on the fabrics. In the medical sectors it is of great importance to limit the development of bacteria or fungi on work tools, on building materials, on clothing. Another field of application of bioactive compounds is that of the prevention of allergies to dust mites.

Agents having biocidal properties have been known for a very long time and are used for example for cosmetic applications or for fungicidal applications. Among these agents, the elements based on metals such as silver, copper or zinc are the best known.

Other agents are described in the literature. Patent EP 0858797 describes for example the use of dendrimers carrying primary amino functions, these functions being neutralized. These agents are formulated in aqueous compositions or in emulsion to be applied in the form of lotions, creams, gels, spray. These agents cannot however be incorporated into thermoplastic polymers and do not withstand the shaping temperatures of the latter.

In order to give biocidal properties to textile surfaces, numerous finishes containing bioactive compounds have been developed. However, these primers always have a limited hold and their effects disappear after one or more washes. It is therefore in many cases more interesting to introduce the active principle directly into the article which must have a bioactive property.

To this end, it is known to introduce a bioactive agent into threads spun in solution or spun by coagulation. The bioactive agent is then introduced into the solvent for the polymer. For polymers formed in the molten phase, it is known to introduce inorganic fillers supporting an element based on bioactive metal. These fillers can be introduced during the polymerization process or during the shaping process. Many solutions are proposed for the realization of mineral charges. These fillers must have sufficient dispersibility in the polymer, an acceptable color and they must not alter the properties of the polymers too much. US Patent 4,775,855, for example, describes the use of silver-bearing zeolites. US Patent 5,180,585 describes mineral fillers comprising three layers, for example a titanium dioxide support, a silver-based layer, a protective layer of silica. The protective layer is described as protecting the polymer from degradation induced by the presence of silver.

The object of the present invention is to propose the use of other agents, which can in particular be introduced into thermoplastic polymers, and which can more particularly be introduced during the polymer shaping phase. To this end, the invention proposes the use as biocidal agent of a complex comprising at least one dendritic polymer and a biocidal compound based on at least one biocidal metal or metal ion.

Dendritic polymers are polymer structures with numerous branches. Among the dendritic polymers, a distinction is generally made between dendrimers and hyperbranch polymers. These two types of structures can be used for the invention.

The term “dendrimer” is understood to mean a polymer structure having regular, tree-like branches, generally controlled, and which may have symmetry. They are for example produced by tree growth of compounds having a functionality greater than 2, the growth being initiated around a core molecule. Such structures are for example described in D.A. Tomalia, A.M. Naylor and W.A. Goddard III Angewangte Chemie, Int. Ed. Engl. 29, 138-175 (1990).

By hyperbranched polymer is meant a branched polymer structure obtained by polymerization in the presence of compounds having a functionality greater than 2, and the structure of which is not perfectly controlled. They are often random copolymers. The hyperbranched polymers can for example be obtained by reaction between, in particular, multifunctional monomers, for example trifunctional and bifunctional, each of the monomers carrying at least two different reactive polymerization functions. Dendritic polymers generally have a substantially globular shape with a size varying from a few nanometers to several tens of nanometers. The ramifications of molecular construction have their ends, the functionality of which can be modulated. By definition the number of ends per macromolecule is greater than 2. Preferred are dendritic polymers compatible with thermoplastic matrices, ie those which can be incorporated homogeneously in a thermoplastic matrix, without significant segregation, and which have a at least partial miscibility with the matrix or which have chemical functionalities compatible with the matrix. Such compatibility can for example be brought about by modulation or modification of the terminal functions of the dendritic polymer. Among the dendritic polymers suitable for the invention, mention may be made of polypropyleneimines with carboxylic functional groups, for example the compounds marketed by the company DSM under the name ASTRAMOL ™, the polyamidoimines with carboxylic ends, for example the compounds marketed by the company Dendritech under the name STARBURST, hyperbranched polyesters functionalized, for example by succinic anhydride, of the type of those sold by the company Perstorp under the name Boltorn.

The complex includes a biocidal compound. By "biocidal object" is meant an object which can prevent the proliferation of certain living species, either by killing them or by limiting their reproduction. In the latter case we also often speak of biostatic objects.

The complex can thus be anti-bacterial, bacteriostatic, antimicrobial, antifungal, anti-mite. It will then be used for these purposes.

In the case where the biocidal compound comprises zinc, in metallic, ionic form, or in the form of an inorganic zinc compound, the complex can be used as a fungicidal or antifungal agent. In the latter case it can also be used as an anti-mite agent, the anti-fungal action eliminating the livelihood of certain mites.

The biocidal compound based on at least one biocidal metal or metal ion is associated with the dendritic polymer to form the complex. The association can for example be obtained by covalent bond, by an ionic interaction or by a chelating force. The biocidal compound is preferably linked to the ends of the chains, optionally functionalized.

The biocidal bodies can be chosen from the following list: metallic silver, its cation Ag +, its oxides, for example Ag ₂ O - metallic copper, its cations Cu + and Cu ++, its oxides CuO and Cu ₂ O, its sulfide CuS , its hydroxides, hydroxycarbonates, oxycations, halides, carbonates metallic zinc, its cation Zn ++, its oxide ZnO and its sulfide ZnS the other compounds and ions from groups 3 to 12 of the international classification, such as Ru, Rh, Pd, Os, Ir, Pt, Au, Hg, Cd, Cr, Ni, Pb They can be used in the compound alone or in combination. By way of example, mention may be made of the combinations of copper and silver ions or of zinc and silver ions.

The preferred dendritic polymers for implementing the invention are hyperbranch copolyesters and hyperbranch copolyamides. More particularly, the preferred copolyamides are non-fully aromatic hyperbranch copolyamides. Such compounds are described in the patent application filed in France on May 5, 1999 under the number 99/05885. They are for example obtained by reaction between:

Has at least one monomer of formula (I) below:

(I) AR-Bf in which A is a reactive polymerization function of a first type, B is a reactive polymerization function of a second type and capable of reacting with A, R is a hydrocarbon entity, and f is the total number of reactive functions B per monomer: f> 2, preferably 2 <f <10; A and at least one monomer of formula (II) below: (II) A'-R'-B 'or the corresponding lactams, in which A', B ', R' have the same definition as that given above respectively for A, B, R in formula (I); characterized -> in that the l / ll molar ratio is defined as follows:

0.05 <l ll and preferably 0.125 <l / ll <2;

- ^ and in that at least one of the entities R or R 'of at least one of the monomers (I) or (II) is aliphatic, cycloaliphatic or arylaliphatic. According to a preferred arrangement of the invention, the hyperbranched copolyamide is characterized in that:

Δ the hydrocarbon-based entities R, R 'of the monomers (I) and (II) respectively, each comprising: yi at least one linear or branched aliphatic radical; y ii and / or at least one cycloaliphatic radical; v iii and / or at least one aromatic radical comprising one or more aromatic rings; these radicals (i), (ii), - (iii) possibly being substituted and / or comprising heteroatoms; Δ A, A 'is a reactive function of the amino type, amine salt, or of the acid, ester, acid halide or amide type; Δ B, B "is a reactive function of the acid, ester, acid halide or amide type or of the amino type, amine salt. Thus, the reactive polymerization functions A, B, A", B 'more especially retained are those belonging to the group comprising the carboxylic and amino functions. By carboxylic function is meant any COOH acid, ester or anhydride function.

In the case where A, A 'corresponds to an amine or to an amine salt, then B, B' represents an acid, an ester, an acid halide or an amide and vice versa.

According to an advantageous variant, the hyperbranched polymer may consist of a mixture of several different monomers (I) and of several different monomers (II), provided that at least one of these monomers is aliphatic, cycloaliphatic or arylaliphatic.

In addition to the multifunctional monomers (I) and the bifunctional monomers (II), it is possible to envisage having a hyperbranched polymer according to the invention also comprising, as constituent elements, mono or multifunctional monomers (III) of the type "core" (or "core") and / or monofunctional monomers

(IV) of the "chain limiter" type.

The “core” type monomers optionally included in the copolyamide and / or hyperbranched ester according to the invention can be those of formula (III) below:

(III) R ¹ (B ") _n in which:

⁰ R ¹ is a substituted or unsubstituted hydrocarbon radical, of the silicone, linear or branched alkyl, aromatic, alkylaryl, arylalkyl or cycloaliphatic radical which may comprise unsaturations and / or heteroatoms; ° B "is a reactive function of the same nature as B or B '; ° n> 1, preferably 1 <n <100.

The monomers of the "chain limiter" type optionally included in the hyperbranched copolyamide according to the invention can be those of formula (IV):

(IV) R ² -A "in which: ° R ² is a substituted or unsubstituted hydrocarbon radical, of the silicone, linear or branched alkyl, aromatic, arylalkyl, alkylaryl or cycloaliphatic type may include one or more unsaturations and / or one or more heteroatoms.

° and A "is a reactive function of the same kind as A or A '. According to an advantageous method, at least a portion of the bifunctional monomers (II) are in the form of prepolymer.

It may be the same with regard to the monomers (III) of the "core" type or even the monomers (IV) of the "chain limiter" type.

The radicals R ¹ and R ² can advantageously comprise functionalities which confer particular properties on the hyperbranched polymer. These functionalities do not react with the functions A, B, A ', B' during the polymerization of the PAHB.

According to a preferred embodiment, f = 2 so that the monomer (I) is trifunctional: ARB ₂ , A = amino function, B = carboxylic function and R = aromatic radical. The hyperbranched polymer obtained from monomers I and II can be likened to tree structures endowed with a focal point formed by the function A and a periphery furnished with terminations B. When they are present, the monomers (III) form nuclei. Advantageously, the hyperbranched polymer can comprise monofunctional monomers (IV) "chain limiter", located on the periphery of the dendrimer according to the invention.

Furthermore, the bifunctional monomers (II) are spacers in the three-dimensional structure. They allow a control of the branch density and are in particular at the origin of the interesting properties of the hyperbranch polymers according to the invention. The monomers (III) and (IV) make it possible to control the molecular weight.

Advantageously, the monomer (I) is for example chosen from the group comprising:

- 5-amino-isophthalic acid,

- 6-amino-undecandioic acid,

- 3-aminopimelic acid, - aspartic acid,

- 3,5-diaminobenzoic acid,

- 3,4-diaminobenzoic acid,

- lysine,

- and their mixtures. Advantageously and for example, the bifunctional monomer of formula (II) is: ε-caprolactam and / or the amino acid corresponding to aminocaproic acid, and / or para or metaaminobenzoic acid, and / or amino-11-undecanoic acid, - and / or lauryllactam and / or corresponding amino acid: amino-12-dodecanoic acid.

More generally, the bifunctional monomers of formula (II) can be the monomers used for the manufacture of linear thermoplastic polyamides.

Thus, mention may be made of ω-aminoalkanoic compounds comprising a hydrocarbon chain having from 4 to 12 carbon atoms, or lactams derived from these amino acids such as ε-caprolactam.

The preferred bifunctional monomer (II) of the invention is ε-caprolactam. By way of examples, the monomers (III) can be, for their part: => saturated aliphatic dicarboxylic acids having from 6 to 36 carbon atoms such as, for example, adipic acid, azeiaic acid, l 'sebacic acid, dodecanoic acid, => linear or branched saturated, preferably aliphatic diamines having from 6 to 36 carbon atoms such as, for example, hexamethylenediamine, trimethylhexamethylene diamine, tetramethylenediamine, n -xylènediamine,

=> Polymeric compounds such as amino polyalkylene oxides sold under the trademark JEFFAMINE ^® = or alternatively silicone chain amine, eg polydimethylsiloxane mono or diamine. = aromatic or aliphatic monoamines,

=> aromatic or aliphatic monoacids, or = aromatic or aliphatic triamines or triacids. The monomers (III), preferred "core" are: hexamethylene diamine and adipic acid, JEFFAMINE ^® T403 or 1,3,5-benzene tricarboxylic acid. According to another characteristic, the molar ratio of the monomers (IV) to the bifunctional monomers (I) is defined as follows:

(IV)

<10

preferably (IV)

- - - <5 () and more preferably still

(IV)

0 <- - -≤ 2

()

Concerning the molar ratio of the functional monomers (III) "nuclei" compared to the multifunctional monomers (I), it can be defined as follows:

_ / __><-,</) ^_ preferably

(/ H)

W ^{sv *} and even more preferably

(///) 0 <-y- ^ ≤ 1/3

Advantageously, the hyperbranched copolyamide can be in the form of particles each consisting of one or more tree structures. Another interesting characteristic of such a copolyamide is the fact that it can be functionalized: 0 at the focal point of the tree structure (s), by means of monomers (III) carrying the functionality or functionalities considered ,

0 and / or at the periphery of the tree structures, via monomers (IV) carrying the functionality or functionalities considered.

As regards the synthetic aspect, it will be specified that the hyperbranch copolyamides can be obtained by a process characterized in that it essentially consists in carrying out a polycondensation between monomers (I) and monomers (II) which react with each other and optionally with monomers (III) and / or (IV); and this under appropriate temperature and pressure conditions. This polymerization takes place in the melt phase, in the solvent phase or in the solid phase, preferably in the melt or solvent phase; the monomer (II) advantageously playing the role of solvent.

The process for the synthesis of hyperbranch polymers according to the invention can use at least one polycondensation catalyst. The polycondensation polymerization is carried out, for example, under conditions and according to a procedure equivalent to those used for the manufacture of the linear polyamide corresponding to the monomers (II).

According to an advantageous embodiment of the invention, the biocidal compound is chosen from silver, copper, zinc cations and their mixtures and the dendritic polymers at least partially have ends of anionic chains, for example ends carboxylate. Without wishing to be bound by any theory, it is very likely that the metal cations are linked to the dendritic polymer by ionic interaction.

By way of example, it is possible to use the hyperbranch copolyamides described above and having carboxylic ends.

Some of these compounds, in particular those having a sufficient connection rate and carboxylic ends, are soluble in basic media. The solubilized compounds can be precipitated for example in ethanol.

To produce a biocidal complex in powder form, the dendrimere can be dissolved in a basic solution, for example a sodium hydroxide solution and then precipitated by adding a silver nitrate solution or by pouring into a silver nitrate solution. This method has no limiting character for the production of the compounds according to the invention comprising an anionic dendrimere and one or more metal cations.

Other methods can be used, for example the dendritic polymer can be dissolved in an organic solvent such as DMF and then precipitated by adding a metal acetate, for example silver acetate. The compound can be stored in the aqueous phase in order to enter into compositions other than thermoplastic compositions, in particular compositions for cosmetic use.

Another solution consists in introducing into the polymerization medium monomers carrying an anionic charge, for example a sulfonated diacid such as sulfo-5-isophthalic acid (AISNa) or a sulfonated amino acid. The anionic function is not necessarily carried by one end of the chain.

According to another embodiment, use is made of dendritic polymers functionalized at the end of the chain or within the chains, so that they exhibit chelating functions of metals or metal cations, for example tertiary amine functions or bi pyridines. The chelating functions can be located at the ends of the chains or be carried within the chains. The invention also relates to the compositions comprising a thermoplastic polymer and a biocidal agent. The biocidal agent is a complex as described above.

The proportion by weight of the biocidal agent in the thermoplastic-based compositions depends on the activity of the compound and on the level of activity desired for the use which will be made of it. It is generally between 0.01 and 10%. The proportion by weight of the biocidal compound in the composition is generally between 5 ppm and 10,000 ppm.

The thermoplastic polymer is advantageously chosen from polyesters, such as PET, PTT, PBT, their copolymers and mixtures, polyamides such as nylon 6, nylon 6.6, nylon 4, polyamides 6-10, 4- 6, 6-36, their copolymers and mixtures.

According to a particular characteristic, the dendritic polymer has terminal functions of which at least a part are compatible with the matrix. Compatibility may be inherent in the chemical nature of the dendritic polymers and the terminal functions it exhibits. This is the case for example for a system consisting of a polyamide matrix and a hyperbranched copendamide dendritic polymer. Compatibility can also be the result of a modification of the terminal groups of a dendrimere, or of a hyperbranched polymer, so as to present alkyl terminations. Such functionalization can be particularly advantageous in the context of use in compositions based on polyolefins such as polypropylene. It is possible, for example, to functionalize iminated polyalkylenes with carboxylic acids containing an alkyl chain with at least 5 carbon atoms.

The compositions can contain all the other additives which can be used, for example reinforcing fillers, flame retardants, UV stabilizers, heat stabilizers, mattifiers.

The compositions according to the invention can be formed into yarns, fibers and filaments by melt spinning. They can also be used in the fields of engineering plastics, for example for the production of molded articles. The biocidal compound can for this purpose be added in the form of powder in an extrusion device upstream of the spinning device. The yarns, fibers and filaments, as well as the textile articles obtained therefrom exhibit biocidal activity.

The compositions are preferably produced by introducing the biocidal compound into the molten polymer. According to another embodiment of the invention, the biocidal compound comes into composition in formulations for sizing fiber and filament yarns, in primer or stain formulations applied to textile surfaces, or in laundry formulations.

Finally, the invention relates to a new complex, comprising a biocidal compound based on a biocidal metal or metal ion and a hyperbranched copolyamide whose terminal functions are anionic or chelating functions, to which the biocidal compound is linked. The hyperbranched copolyamide is as described above.

According to a preferred characteristic, the biocidal compound is chosen from metallic silver, metallic copper, metallic zinc, their cations, their oxides and sulfides, and mixtures of these compounds. Compounds which may be suitable have been described above.

Other details and advantages of the invention will become apparent in the light of the examples below, given only for information.

The antibacterial or bacteriostatic activity of the compounds and compositions containing them is measured according to the test called "Shake Flask Test" and described in US Pat. No. 4,708,870. The operating protocol for the test is as follows:

1 g of product to be tested is brought into contact with 70 ml of phosphate buffer at pH 7.2 and 5 ml of a bacterial suspension at 1-3 10 ⁵ CFU / ml in a 250 ml Erlenmeyer flask. A powder-free Erlenmeyer flask is used as a control test. The bacterial strain used is Klebsiella pneumoniae. The Erlenmeyer flasks are stirred at 300 movements per minute at room temperature. A count of bacteria is carried out after 0, 1 and 24 hours of incubation. A reduction rate is defined by the ratio between the difference between the number of bacteria before and after incubation and the number of bacteria before incubation (measurement at 0 hours).

The activity of textile surfaces is measured according to standard JIS L1902: 1998, with the following operating conditions:

- We use the bacterium Staphylococcus aureus ATCC 4352, initially kept dry and frozen. The cultures are inoculated on a nutritive basis (LAB8, LabM), and incubated at 37 ° C for 48 hours. The bacteria are then transferred into 250 ml Erlenmeyer flasks, on a nutritional basis (LAB14, LabM) and incubated at 37 ° C for 18 to 24 hours. The culture is diluted 1/20 with isotonic saline solution (0.85% by weight), so that the suspension comprises approximately 10 ⁵ bacteria per ml. - The tests are carried out on knitted surfaces of 18 mm by 18 mm. The surfaces weigh at least 0.4 g. The samples tested are: a polyester control sample - the control samples and the samples according to the invention.

The surfaces are placed in 30 ml bottles. Six bottles are prepared comprising control samples and three bottles for each sample to be tested. The bottles are covered with a film, and sterilized at 121 ° C for 15 minutes. The samples included in the bottles are inoculated with 0.2 ml of the bacteria suspension, taking care not to bring the suspension into contact with the walls of the bottle. Immediately after inoculation, 20 ml of a Tween 80 isotonic solution (0.2% by weight) is added to three of the bottles containing the control samples, closed with a sterile stopper, and shakes them for 30 seconds. There are the number of bacteria.

The other bottles are placed in a desiccator, and the bacteria are incubated for 18 hours at 37 ° C. After incubation the number of bacteria is counted as the number of bacteria at time zero. The following are determined: - The number A of bacteria on the control samples at 0 o'clock.

The B number of bacteria on the control samples at 24 hours. The C number of bacteria on the test samples is 24 hours.

Example 1 Manufacture of a hyperbranched copolyamide with sodium carboxylate ends

A hyperbranched copolyamide is produced according to the example of the patent application filed in France on May 5, 1999 under the number 99/05885, the synthesis of a hyperbranched copolyamide with carboxylic acid terminations by copolycondensation in the molten phase of acid 1, 3,5-benzene tricarboxylic (core molecule (iii) of type R ¹ - B " ₃ , with B = COOH), 5-aminoisophthalic acid (branching molecule (I) of type ARB ₂ , with A = NH ₂ ) and ε-caprolactam (spacer (II) of type A'-R'-B '). The reaction is carried out at atmospheric pressure and with light nitrogen sweeping in a 7.5 I autoclave commonly used for the melt phase synthesis of polyesters or polyamides. The monomers are fully charged at the start of the test. Successively introduced into the reactor 1811.5 g of 5-aminoisophthalic acid (10 mol), 84 g of 1,3,5-benzene tricarboxylic acid (0.4 mol), 1,131.6 g of ε-caprolactam (10 mol) and 1.35 g of a 50% (w / w) aqueous solution of hypophosphorous acid. The reaction mass is placed under stirring (speed = 50 rpm) and gradually heated from 20 to 200 ° C in 100 min., Then from 200 to 250 ° C in 60 min. Distillation begins at a temperature of 160 ° C and continues until the temperature of 245 ° C. At 250 ° C, the system is gradually put under vacuum until reaching an absolute pressure of 5 mbar after 30 min. The reactor is then placed under nitrogen overpressure and the polymer drained by the bottom valve.

The water contained in the 221.06 g of distillate collected is titrated using a Karl Fischer couiometer. The water content of the distillate is 81.1%, which translates into an overall progress rate of 99.3%.

150 g of the copolyamide obtained are dissolved at room temperature and with stirring in a beaker containing 570 ml of aqueous sodium hydroxide at 40 g / l. The solution is then poured dropwise and with stirring into 5 liters of absolute ethanol. A white precipitate is obtained which is isolated by filtration on sintered glass No. 4. The filter cake is rinsed 3 times with 100 ml of ethanol and then dried under the vacuum of a vane pump at 80 ° C for 16 hours. The hyperbranched copolyamide with sodium carboxylate ends thus obtained is characterized in elementary analysis. The sodium level measured experimentally is 7.47% by mass.

Example 2 - Manufacture of a biocidal compound - Ag 120 grams of a hyperbranched copolyamide with sodium carboxylate ends as described in Example 1 are dissolved at room temperature in 500 ml of demineralized water. The solution obtained is transferred to a dropping funnel and added dropwise to an aqueous solution of silver nitrate (68.33 g of AgNO ₃ in 400 ml of water) placed under stirring and protected from light. A pink-white precipitate is obtained which is retained on a sintered filter No. 5. The filter cake is washed with demineralized water until no more Ag ⁺ cations are detected in the washing water (precipitation test with an aqueous solution of sodium chloride). It is then dried under the vacuum of a vane pump at 80 ° C for 16 hours. The hyperbranched copolyamide with silver carboxylate ends thus obtained is characterized in elementary analysis. Its mass content of silver is 28.4%. There remains a residual sodium content of 0.87% by mass. Example 3 - Manufacture of a biocidal compound - Zn

200 grams of a hyperbranched copolyamide with sodium carboxylate ends as described in Example 1 are dissolved at room temperature in 800 ml of demineralized water. The solution obtained is transferred to a dropping funnel and added dropwise to an aqueous solution of zinc sulfate (110 g of ZnSO, 7 H ₂ 0 dissolved in 900 ml of water) placed under stirring. A white precipitate is obtained which is retained on a No. 4 sintered filter. The filter cake is washed with 3 x 500 ml of demineralized water. It is then dried under the vacuum of a vane pump at 80 ^β C for 16 hours. The hyperbranched copolyamide with zinc carboxylate ends thus obtained is characterized by elementary analysis. Its mass zinc content is 9.9%. There remains a residual sodium content of 1.15% by mass.

Example 4 - Manufacture of a biocidal compound - Ag / Zn 200 grams of a hyperbranched copolyamide with sodium carboxylate ends as described in Example 1 are dissolved at room temperature in 800 ml of demineralized water. The solution obtained is transferred to a beaker placed under magnetic stirring. An aqueous solution of silver nitrate (39.3 g of AgNO ₃ in 350 ml of water) is added thereto dropwise. We observe the fleeting formation of a white precipitate which redissolves as it forms. Once the addition of the silver nitrate solution is complete, the contents of the beaker are transferred to a dropping funnel and added dropwise to a solution of zinc sulfate (73.2 g of ZnSO ₄ , 7 H ₂ 0 dissolved in 700 ml of water) placed under stirring. During the entire duration of these operations, the solutions are protected from light. A white precipitate is obtained which is retained on a No. 4 sintered filter. The filter cake is then dried under vacuum with a vane pump at 80 ° C for 16 hours. The hyperbranched copolyamide with mixed ends zinc carboxylates and silver carboxylates thus obtained is characterized in elementary analysis. Its mass content of zinc is 6.0% and that of silver 9.6%. There remains a residual sodium content of 1.8% by mass.

Example 5 - Manufacture of a biocidal compound - Ag / Cu

114 grams of a hyperbranched copolyamide with sodium carboxylate ends as described in Example 1 are dissolved at room temperature in 456 ml of demineralized water. The solution obtained is transferred to a beaker placed under magnetic stirring. An aqueous solution of copper sulphate (17.9 g of CuSO ₄ , 5 H ₂ O in 180 ml of water) is added thereto dropwise. The formation of a blue precipitate is observed which redissolves after a few minutes with stirring. Once the addition of the copper sulphate solution completed, the contents of the beaker are transferred to a dropping funnel and added dropwise to a solution of silver nitrate (40.6 g of AgNO ₃ in 460 ml of protected from light. A sky-blue precipitate is obtained which is retained on a sintered filter No. 4. The filter cake is then dried under the vacuum of a vane pump at 80 ^C C for 16 hours. The hyperbranched copolyamide with mixed ends copper carboxylates and silver carboxylates thus obtained is characterized in elementary analysis. Its mass content of copper is 3.0% and that of silver 15.8%. There remains a residual sodium content of 2.0% by mass.

EXAMPLE 6 Manufacture of Polyamide-Based Compositions

Polyamide 66 granules with a viscosity index of 140.6 ml / g (measurement at 25 ^β C in a Hubbelhode viscometer of a solution of 5 g / l of polymer dissolved in a mixture composed of 90% by weight formic acid and 10% by weight of water), are dried at 80 ° C. under vacuum for 16 hours. Biocidal compounds according to Examples 3 to 5 are incorporated into the polyamide using a Leistriz twin-screw extruder

30.34. The compositions obtained are ground by cryogenic milling into a powder of which 90% of the grains have a diameter of less than 850 μm.

The characteristics of the compositions are specified in Table 1.

Comparative example 1

A control sample not containing a biocidal compound is produced under the same conditions as Example 6. (composition D0).

Table 1

The biocidal activity of the compositions is tested according to the protocol described above. A powder-free test control is carried out. The results are specified in Table 2. Table 2

Example 7.

Yarns (130 dtex, 20 filaments) comprising 0.2% by weight of a compound according to Example 3 are produced. These yarns are obtained from compositions produced according to Example 6.

A knitting is made from the yarns produced, for the measurement of the antibacterial activity according to standard JIS L1902: 1998.

The tests are carried out on knitted fabrics which have not undergone washing or on fabrics which have been washed according to ISO 6330 standard.

The test results are presented in Table 3

Comparative Example 2 Tests are carried out on knits according to Example 7, using threads not comprising a biocidal agent. The test results are presented in Table 3.

Table 3

Claims

1. Use as a biocidal agent of a complex comprising a dendritic polymer and a biocidal compound based on at least one biocidal metal or metal ion.

2. Use according to claim 1 characterized in that the dendritic polymer and the biocidal compound are linked by ionic or chelating interaction

3. Use according to one of claims 1 or 2 characterized in that the biocidal compound is chosen from metallic silver, metallic copper, metallic zinc, their cations, their oxides and sulfides, and mixtures of these compounds.

4. Use according to one of claims 1 to 3 characterized in that the dendritic polymer is a dendrimere.

5. Use according to claim 1 or 2 characterized in that the dendritic polymer is a hyperbranched polymer.

6. Use according to claim 5 characterized in that the dendritic polymer is a hyperbranched copolyamide or a hyperbranched copolyester.

7. Use according to one of the preceding claims, characterized in that the proportion by weight of the biocidal compound is between 0.05 and 99.5% relative to the total weight of the complex.

8. Use according to one of the preceding claims characterized in that the biocidal compound is chosen from cations of silver, copper, zinc, or mixtures thereof, the cations being linked by ionic interaction with a dendritic polymer having anionic groups.

9. Use according to claim 8 characterized in that the anionic groups are carried by chain ends of the dendritic polymer.

10. Use according to one of claims 8 or 9 characterized in that the anionic groups are carboxylates.

11. Use according to one of claims 1 to 10 characterized in that the dendritic polymer is a hyperbranched copolyamide obtained by reaction between:

- at least one monomer of formula (I) below:

(I) AR-Bf in which A is a reactive polymerization function of a first type, B is a reactive polymerization function of a second type and capable of reacting with A, R is a hydrocarbon entity optionally comprising heteroatoms, and f is the total number of reactive functions B per monomer: f> 2, preferably 2 <f <10;

- And at least one bifunctional monomer of formula (II) below: (II) A'-R'-B 'or the corresponding lactams, in which A', B ', R' have the same definition as that given above respectively for A, B, R in formula (I); characterized in that the l / ll molar ratio is defined as follows:

0.05 <l / ll and preferably 0.125 <l / ll <2; and in that at least one of the entities R or R 'of at least one of the monomers (I) or (II) is aliphatic, cycloaliphatic or arylaliphatic.

12. Use according to claim 11 characterized in that: • the hydrocarbon-based entities R, R 'of the monomers (I) and (II) respectively, each comprising: at least one linear or branched aliphatic radical; and / or at least one cycloaliphatic radical; iii. and / or at least one aromatic radical comprising one or more aromatic rings; these radicals (i), (ii), (iii) possibly being substituted and / or comprising heteroatoms; *> and in that,

- A, A 'is a reactive function of the amino type, amine salt or of the acid, ester, acid halide or amide type;

- B, B 'is a reactive function of the acid, ester, acid halide or amide type or of the amino type, amine salt.

13. Use according to one of claims 11 to 12 characterized in that the reactive polymerization functions A, B, A ', B' are chosen from the group comprising the carboxylic and amino functions.

14. Use according to one of claims 11 to 13 characterized using "core" monomers of formula (III) to obtain the hyperbranched copolyamide:

(III) R ¹ (B ") _n in which:

R ¹ is a substituted or unsubstituted hydrocarbon radical, of the silicone, linear or branched alkyl, aromatic, alkylaryl, arylalkyl or cycloaliphatic type, which can comprise unsaturations and / or heteroatoms; B "is a reactive function of the same nature as B or B '; - n> 1, preferably 1 <n <100.

15. Use according to one of claims 11 to 14 characterized in that "chain-limiting" monomers of formula (IV) are used to obtain the hyperbranched copolyamide: (IV) R ² -A "in which:

- R ² is a substituted or unsubstituted hydrocarbon radical, of the silicone, linear or branched alkyl, aromatic, arylalkyl, alkylaryl or cycloaliphatic radical which may comprise one or more unsaturations and / or one or more heteroatoms.

- and A "is a reactive function of the same nature as A or A '.

16. Use according to one of claims 11 to 15 characterized in that the monomer of formula (I) is a compound in which A represents the carboxylic acid function, B the amino function, R an aromatic radical and f = 2.

17. Use according to one of claims 1 to 16 as an anti-bacterial agent.

18. Use according to one of claims 1 to 16 characterized in that the biocidal compound is based on zinc, the agent being used as anti-fungal.

19. Composition comprising a thermoplastic polymer and a biocidal agent, characterized in that the biocidal agent is a complex as defined in one of claims 1 to 18, at least part of the end groups of the dendritic polymer being compatible with the thermoplastic polymer.

20. Biocidal composition according to claim 19 characterized in that the proportion by weight of the biocidal agent is between 0.01 and 10%.

21. Biocidal composition according to one of claims 19 or 20, characterized in that the thermoplastic polymer is chosen from polyesters and polyamides.

22. Yarns, fibers and filaments obtained by melt spinning from a composition according to one of claims 19 to 21.

23. Textile articles obtained from fiber and filament yarns according to claim 22.

24. Complex comprising a biocidal compound based on at least one biocidal metal or metal ion, characterized in that it comprises a hyperbranched copolyamide whose terminal functions are anionic or chelating functions, to which the biocidal compound, hyperbranched copolyamide being as defined in claim 16.

25. Complex according to claim 24 characterized in that the biocidal compound is chosen from metallic silver, metallic copper, metallic zinc, their cations, their oxides and sulfides, and mixtures of these compounds.